JP7756913B2 - Lifting device - Google Patents

Description

The present invention relates to a care lift device that lifts a care recipient and assists them in moving (transferring) from a care device such as a bed to another care device such as a wheelchair.

In nursing care settings, nursing care lift devices that assist caregivers in lifting care recipients are effective in preventing back pain by reducing the workload on caregivers. In recent years, there has been a trend toward using these nursing care lift devices to improve the nursing care environment by eliminating the need for caregivers to lift care recipients, making it easier to secure nursing care personnel.

An example of such a conventional nursing care lift device is disclosed in Japanese Patent No. 2998843.

Patent No. 2998843

As shown in the above-mentioned patent document, the conventional lift device is designed so that a drive mechanism is activated by operating an operating section provided on the lift body, thereby moving the care recipient.
In such conventional lift devices, a remote switch (remote control) was often used for operation so that a caregiver could operate the lift device while standing nearby and providing assistance to the care recipient by moving the care recipient using the lift device.

When using such a remote switch to operate a lift device, caregivers must pay close attention to the safety of the person being cared for while providing assistance and operating the remote switch.

When using a lift device in a care setting, the caregiver must move around the care recipient multiple times, checking safety before operating the remote switch to move the lift device. However, when the remote switch is connected to the lift main unit via a wired connection, there is a connection cord between the remote switch and the lift main unit, and part of the connection cord may become tangled with equipment around the care recipient or the care recipient themselves, or may become trapped under the care recipient's body. In such cases, the connection cord, which cannot be extended to its full length, restricts the remote switch's range of motion, making it difficult to operate, and also placing strong stress on the connection cord, which could potentially cause the connection cord to break.

Furthermore, when using a lift device to raise or lower a care recipient onto or from a bed, wheelchair, or other care equipment, it is ideal for the caregiver to support the care recipient with both hands, paying attention to prevent swaying, torso tilt, arms getting caught, belts coming undone, and falls. However, when using a remote switch, the remote switch is actually operated with one hand, meaning the care recipient is supported with only the other hand, i.e., one hand. Using a remote switch requires the caregiver to pay even more attention, making the task more difficult for the caregiver and posing a problem that can easily lead to caregivers avoiding using the lift. In addition, supporting the care recipient with one hand can make the caregiver feel uneasy.

The present invention was made to solve the above-mentioned problems, and aims to provide a lift device that allows the caregiver to assist the care recipient in moving using a lift without having to operate the lift while assisting the care recipient, making it possible to assist the care recipient in moving without strain.

The lift device disclosed in the present invention comprises a movable main body frame, a lifting mechanism attached to the main body frame for suspending and raising and lowering a sling carrying a care recipient, a detection means for detecting a load applied to the lifting mechanism, and a control unit for controlling the operation of the lifting mechanism, wherein the control unit is capable of executing power assist control to calculate the assisting force from the caregiver applying to the care recipient based on the load detected by the detection means and to operate the lifting mechanism in accordance with the obtained assisting force, and is capable of moving the care recipient from a predetermined first care appliance to a second care appliance. This care lift device further comprises an operation unit having one or more switches, including at least an automatic control switch that issues a predetermined control instruction to the control unit, and when the control unit receives an initial operation input to the automatic control switch, operates the lifting mechanism in an upward movement control mode for the care recipient positioned on the first care appliance, thereby raising the sling carrying the care recipient, and interrupts the operation of the lifting mechanism one or more times during the lifting to temporarily suspend the lifting. The system continues to lift the care recipient while lifting the lifting device. As the care recipient transitions from the first care appliance to a separated state due to the lifting, if the load detected by the detection means does not increase or change for a predetermined period of time, the system stops lifting the lifting device using the lifting mechanism and terminates the upward movement control mode. The system then transitions the lifting mechanism to the power assist control state, either automatically or in response to an operation input to a predetermined switch. In the power assist control state, if a new operation input is received by the automatic control switch while the care recipient is in the power assist control state, the system switches to downward movement control mode, allowing the care recipient to descend using power assist control in accordance with the downward assist force applied to the care recipient. Furthermore, as the care recipient's descent progresses, if the load detected by the detection means decreases to a predetermined value, the system switches to a state in which the lifting mechanism is activated to automatically lower the care recipient without relying on an assist force. As the care recipient transitions from the descent to a state in which the care recipient is supported by the second care appliance, if the load detected by the detection means does not decrease or change for a predetermined period of time, the system stops operation of the lifting mechanism and terminates the downward movement control mode.

According to the disclosure of the present invention, when assisting a care recipient to move from a first care device to a second care device, the control unit first operates in an upward movement control mode to lift the care recipient supported by the first care device by operating the lifting mechanism, continues to lift the care recipient with one or more pauses, and when the care recipient reaches a state where it is properly supported by the lift device alone, switches to a power assist control mode. After the care recipient moves upward to the second care device under power assist control, the control unit switches to a downward movement control mode to allow the care recipient to descend toward the second care device with the caregiver's assistance under power assist control. When the care recipient is partially supported by the second care device and the reduction in the load supported by the lifting mechanism reaches a predetermined percentage, switches to an automatic lowering mode to further lower the care recipient, and then lowers the care recipient to the second care device. The lifting mechanism, which moves the care recipient up and down, is supported only by the device, eliminating the need for the caregiver to use any operating means on the mechanism in parallel with the movement of the care recipient. This means that during the process of lifting the care recipient from the first care device until the power assist control state is reached, where the caregiver can move the care recipient up and down directly with minimal force with the assistance of the lifting mechanism, and during the process of moving the care recipient from the power assist control state to the second care device, the caregiver can assist with the movement of the care recipient without simultaneously operating the lifting mechanism. This means that in various situations where assistance is required for moving the care recipient, the caregiver can focus on assisting, for example by placing both hands on the care recipient, ensuring safety during the movement of the care recipient.

In addition, by temporarily stopping the process of lifting the care recipient from the first care device and preventing the care recipient from moving, the caregiver is given an opportunity to carry out their work without interfering with the care recipient or their surroundings. During this pause, the caregiver can correct any problems that have become apparent during the movement up to that point, such as the state of support of the care recipient in the sling, thereby preventing a situation in which the care recipient is left in an inappropriate state while the movement continues and adversely affecting the care recipient.

In addition, in the lift device disclosed herein, the control unit temporarily suspends the lifting of the care recipient in the upward movement control mode when the load detection value detected by the detection means reaches a predetermined reference value.

As described above, according to the disclosure of the present invention, in the upward movement control mode of the control unit, the timing for temporarily suspending the lifting of the care recipient by the lifting mechanism is set to the point when the load detected by the detection means reaches a preset reference value, and the lifting is paused based on the increasing change in the load detection value that accompanies the lifting. By setting an appropriate reference value, for example, a value equivalent to the load detection value when the care recipient has risen slightly and is being supported by both the lift device and the first care appliance, the lifting can be paused at an appropriate time, not when the weight of the care recipient is too low on the sling and problems with the support of the care recipient by the sling have not yet been identified, nor when the weight of the care recipient is too high and the support of the care recipient by the sling cannot be changed, providing an appropriate opportunity to correct the support of the care recipient by the sling.

In addition, in the lift device disclosed in the present invention, the control unit sets, as necessary, a reference value for the load detection value related to the timing for temporarily suspending the lifting of the care recipient in the upward movement control mode, based on the weight of the care recipient that has been detected in advance.

As described above, according to the disclosure of the present invention, in the upward movement control mode of the control unit, the reference load value related to the timing for temporarily pausing the lifting of the care recipient by the lifting mechanism is set for each care recipient based on the care recipient's weight. This allows for an appropriate reference value to be set for each care recipient, corresponding to the degree of change in the load detection value as the lifting progresses, which differs depending on the care recipient's weight. This allows the lifting to be temporarily paused in the appropriate situation even when the care recipient changes, and allows the caregiver to perform tasks during the paused state, such as adjusting the support status of the care recipient with the lifting device, without any problems.

Furthermore, the lift device disclosed in the present invention transitions to downward movement control mode as necessary when the control unit receives an operation input to the automatic control switch while in power assist control mode and the caregiver is not assisting the care recipient or operating the lifting mechanism.

As disclosed herein, when the control unit is in the power assist control state and the caregiver is not performing any assisting operations, no assisting force is being applied and the lifting mechanism is not operating, the control unit controls the transition to downward movement control mode upon receiving an operation input from the automatic control switch. If the care recipient is already positioned above the second care appliance, the caregiver can operate the control unit to lower the care recipient toward the second care appliance, and the care recipient can then be automatically lowered to complete the descent. This allows the control unit to remain in the power assist control state and move the care recipient appropriately until the caregiver performs operations to assist the care recipient in moving the care recipient and correctly position the care recipient above the second care appliance. However, once the care recipient has reached the top of the second care appliance and no operations other than lowering the care recipient are required, the control unit can switch to downward movement control mode at the caregiver's desired timing, allowing the care recipient to be moved smoothly and quickly to the second care appliance.

In addition, the lift device disclosed in this invention can also be configured as follows, if necessary.

When the control unit of the lift device disclosed in the present invention receives an operation input to the automatic control switch while in power assist control mode and the lifting mechanism is operating to move the care recipient, it temporarily suspends power assist control, acquires and sets a new load equivalent to the weight of the care recipient as the reference load value for calculating the assist force in power assist control, and then resumes power assist control.

According to the disclosure of the present invention, when the control unit is in power assist control mode and is operating the lifting mechanism to move the care recipient, if the control unit receives an operation input from the automatic control switch, the power assist control is temporarily stopped, a new load equivalent to the weight of the care recipient is detected and acquired, and this is set as the load reference value required for power assist control. The power assist control is then resumed, and the lifting mechanism is operated according to the assisting force calculated based on the new reference value. In this case, for example, if an incorrect reference value is set because the caregiver's assisting force used to operate the care recipient is recognized as part of the care recipient's static load, and the control unit erroneously determines that an assisting force is being applied due to the discrepancy between the incorrect reference value and the true load when the caregiver is not performing movement assistance operations, and activates the lifting mechanism, resulting in inappropriate movement of the care recipient, the caregiver can immediately stop the power assist control and correct the incorrect load reference value set by the control unit. This makes it easier to ensure the accuracy and safety of the care recipient's movement under power assist control, and eliminates the need for a separate operating means such as a switch to stop power assist control and resume control after normalization, thereby reducing the cost of the device.

Furthermore, in the lift device disclosed in the present invention, the control unit continues the temporary suspension of the lifting of the care recipient in the upward movement control mode as needed while the detection means detects a change in load associated with the caregiver performing a specified care assistance task.

As described above, according to the disclosure of the present invention, when the control unit's upward movement control mode temporarily suspends the lifting of the care recipient by the lifting mechanism, the paused state is maintained while the detection means detects a change in load associated with the caregiver performing a procedure on the care recipient or the lifting device as part of the caregiver's assistive care work. By not resuming the lifting of the care recipient while the caregiver is performing the assistive care work, the caregiver can be assured of a state in which they can perform the assistive care work without strain, and once the lifting is resumed, safe lifting can be achieved under the correct support conditions.

Furthermore, in the lift device disclosed in the present invention, if necessary, the control unit temporarily suspends the movement of the care recipient when it receives an operation input to the automatic control switch in at least one of the following states: a state in which the care recipient is further raised after the lifting of the care recipient is temporarily suspended in the upward movement control mode; and a state in which the care recipient is automatically lowered in the downward movement control mode.

As disclosed in this invention, when the control unit receives an operation input to the automatic control switch while further raising the care recipient after pausing in the upward movement control mode or while automatically lowering the care recipient in the downward movement control mode, the control unit controls the movement of the care recipient to pause, providing an opportunity to stop the care recipient's movement. This allows the caregiver to immediately stop the movement of the care recipient and resolve the inappropriate condition if the care recipient is mistakenly raised in an improperly supported state or lowered in a position that prevents the care recipient from properly contacting the second care appliance, in addition to the normal pause in the ascent process in the upward movement control mode. This makes it easier to ensure the safety of the care recipient's movement, and by enabling the automatic control switch to be used as an operating means for pausing, there is no need to provide a separate operating means such as a switch to instruct the care recipient to stop movement, thereby reducing the cost of the device.

Furthermore, in the lift device disclosed in the present invention, if necessary, the control unit cancels the paused state when it receives an operation input to the automatic control switch during at least one of the paused state during the lifting of the care recipient in the upward movement control mode and the paused state during the automatic lowering of the care recipient in the downward movement control mode.

As disclosed in this invention, when the control unit receives an operation input to the automatic control switch during a pause in the ascent of the care recipient in the upward movement control mode or the automatic descent of the care recipient in the downward movement control mode, the control unit activates the lifting mechanism and controls the device to cancel the pause, thereby resuming the movement of the care recipient. If the care recipient's improper support state or other condition is resolved during the pause in the movement and the care recipient is once again in a state where it can be moved, the caregiver can immediately return to the state of moving the care recipient at their discretion, allowing the movement of the care recipient to be completed quickly. Furthermore, by using the automatic control switch as an operation means for canceling the pause, there is no need to provide a separate operation means such as a switch for issuing an instruction to cancel the pause, thereby reducing the cost of the device.

1 is a perspective view of a lift device according to a first embodiment of the present invention; 1 is a block diagram of a lift device according to a first embodiment of the present invention. 1 is an explanatory diagram illustrating a state in which the lift device according to the first embodiment of the present invention starts to lift a care recipient. FIG. 1 is an explanatory diagram illustrating a state in which a care recipient is being lifted by the lift device according to the first embodiment of the present invention; FIG. 4 is a flowchart of control in an upward movement control mode in the lift device according to the first embodiment of the present invention. 4 is a flowchart of power assist control in the lift device according to the first embodiment of the present invention. 1 is an explanatory diagram illustrating a state in which a care recipient is being lowered by the lift device according to the first embodiment of the present invention; FIG. FIG. 10 is an explanatory diagram of a state in which the lift device according to the first embodiment of the present invention has finished lowering a care recipient. 4 is a flowchart showing the main part of a control in a downward movement control mode in the lift device according to the first embodiment of the present invention. 10 is a supplementary flowchart of control in a downward movement control mode in the lift device according to the first embodiment of the present invention. FIG. 10 is an explanatory diagram showing a state in which a care recipient is being lifted by a lift device according to a second embodiment of the present invention. FIG. 10 is an explanatory diagram showing a state in which a care recipient is being lowered by a lift device according to a second embodiment of the present invention. FIG. 10 is a block diagram of a lift device according to a third embodiment of the present invention. 10 is a flowchart of power assist control in a lift device according to a third embodiment of the present invention. 10 is a flowchart of control in an upward movement control mode in a lift device according to a fourth embodiment of the present invention.

(First embodiment of the present invention)
A lift device according to a first embodiment of the present invention will be described below with reference to FIGS. 1 to 10. FIG.
In this embodiment, an example of a floor-traveling type lift device that can move from the vicinity of a first care apparatus where a care recipient is to be moved to the vicinity of a second care apparatus where the care recipient is to be moved will be described.

In the above figures, the lift device 1 according to this embodiment comprises a movable main body frame 10, a lifting mechanism 11 attached to the main body frame 10 and used to suspend and raise and lower the lifting device 50 carrying the care recipient 80, a sensor 12 as a detection means for detecting the load applied to the lifting mechanism 11, an operation unit 13 that accepts various operational inputs from the caregiver 90 related to the up and down movement of the care recipient 80 by the lifting mechanism 11, and a control unit 14 that controls the operation of the lifting mechanism 11.

The main frame 10 has a base portion 10a that contacts the ground or floor surface and supports the entire lift device, and a pillar- or tower-shaped upright portion 10b that protrudes upward from the base portion 10a.
The base portion 10a has a plurality of wheels that can roll on the ground or floor surface, and is movable relative to the ground or floor surface. An upright portion 10b is provided at the rear of the base portion 10a.

A handle 10c is attached to the top of the standing section 10b, which the caregiver 90 holds when moving the entire lift device. To allow the caregiver 90 to easily change the direction of movement when using this handle 10c to move the lift, some of the wheels on the base section 10a can be attached so that they can rotate around an axis perpendicular to the base section 10a.

The lifting mechanism 11 comprises a roughly arm-shaped arm 11a that is tiltably connected to the upper part of the standing portion 10b of the main frame 10, an actuator 11b that is interposed between the arm 11a and the standing portion 10b and tilts the arm 11a by extending and contracting, and a hanger portion 11c that is provided at the tip of the arm 11a and can hang a lifting device 50.

Actuator 11b is a known linear actuator that moves a movable part attached to arm 11a in a straight line relative to a fixed part attached to upright section 10b. Actuator 11b can also be configured to operate, for example, by rotating a screw shaft with an electric motor and moving a retractable shaft part that threads onto the screw shaft.

The actuator 11b operates by moving the movable part back and forth relative to the fixed part, causing the entire device to expand and contract, tilting the arm 11a relative to the standing part 10b of the main frame 10. Via the hanger part 11c at the end of the arm 11a and the hanging device 50 suspended from it, the care recipient 80 can be raised and lowered relative to the first care device and the second care device, which are a bed 60 and a wheelchair 70, and can be placed in a state where they are supported in contact with these devices, or in a state where they are not supported away from these devices.

The hanger portion 11c is formed in a shape similar to that of a general clothes hanger, and is attached to the tip of the arm 11a so as to have a degree of freedom to rotate around a plurality of axes.
The hanger portion 11c has hooks at both ends, and is designed to allow the ends (strings) of a sheet-like sling 50 for suspending the care recipient 80 to be hung thereon.

The sensor 12 is disposed between the hanger portion 11c and the arm 11a of the lifting mechanism 11, and detects the vertical load applied to the arm 11a via the hanger portion 11c as the load applied to the lifting mechanism 11. When the care recipient 80 is suspended from the hanger portion 11c of the lifting mechanism 11 by the sling 50, the weight of the care recipient 80 is included in the load detected by the sensor 12.
The sensor 12 may be, for example, a load cell (strain gauge).

This sensor 12 is electrically connected to the control unit 14 and outputs the detected load as a signal to the control unit 14. When the output signal from the sensor 12 is input to the control unit 14, the control unit 14 compares the load obtained from the signal with a reference value based on the weight of the care recipient 80, and if the load is greater than the reference value, it determines that the sling 50 carrying the care recipient 80 is being pushed downward. Conversely, if the load is less than the reference value, it determines that the sling 50 is being lifted upward.

The operation unit 13 has multiple switches that accept operation inputs related to various operational instructions for the lift device 1, including raising and lowering the care recipient 80 suspended by the lifting mechanism 11, and is disposed near the connection between the arm 11a of the suspension mechanism 11 and the main frame 10, and is capable of transmitting operation inputs to the switches to the control unit 14.

The operating unit 13 is configured to include switches such as an automatic control switch 13a that causes the control unit 14 to perform predetermined control, an up switch 13b that causes the actuator 11b to tilt the arm 11a upward and raise the care recipient 80, and a down switch 13c that causes the actuator 11b to tilt the arm 11a downward and lower the care recipient 80.

The operating unit 13 can be located in a position other than near the connection between the arm 11a of the hanging mechanism 11 and the main frame 10, as long as it is easy for the caregiver to operate the switch with their hands or feet and is unlikely to cause unintended contact that could lead to erroneous operation. For example, it can be located on the upright portion 10b or base portion 10a of the main frame 10.

Furthermore, the switches of the operating unit 13 are not limited to those that can be switched ON/OFF by direct operation with a hand, foot, etc., but can also be those that recognize specific voices, human movements, or gestures as operations and perform the switch function. In this case, the switches may be capable of realizing the switch function by recognizing the movements of the care recipient 80 themselves.

The control unit 14 controls the operation of the lifting mechanism 11 based on operations from the operating unit 13 or preset procedures, and is also capable of calculating the assisting force applied by the caregiver 90 to the care recipient 80 as a direct assisting operation based on the load detected by the sensor 12 serving as the detection means, and performing power assist control to operate the lifting mechanism 11 according to the obtained assisting force.

When the control unit 14 receives an operation input to the raising switch 13b of the operating unit 13, while the switch is in the ON state, it activates the actuator 11b to tilt the arm 11a upward, thereby raising the care recipient 80 together with the sling 50. Furthermore, when the control unit 14 receives an operation input to the lowering switch 13c, while the switch is in the ON state, it activates the actuator 11b to tilt the arm 11a downward, thereby lowering the care recipient 80.

Furthermore, when the control unit 14 receives an operation input to the automatic control switch 13a of the operation unit 13, it executes a series of controls, including an upward movement control mode and a downward movement control mode, along with power assist control, corresponding to the process of moving the care recipient 80 from the first care device to the second care device, to operate the lifting mechanism 11.

However, if an operation input is received to the ascent switch 13b or descent switch 13c while the lifting mechanism 11 is being operated under control in the upward movement control mode or downward movement control mode, the system will stop each of the above controls and prioritize control of activating the actuator 11b of the lifting mechanism 11 to raise or lower the care recipient 80 based on the operation input to the ascent switch 13b or descent switch 13c.

Power assist control is a well-known control method that, when an operator applies an operating force in the direction of movement to a supported object supported by a lift device through direct movement assistance operations by the operator to raise or lower the supported object, calculates the operating force applied by the operator to move the supported object by subtracting a load based on the weight of the supported object from the total load of the supported object detected by the load detection means of the lift device, and activates a drive mechanism related to supporting the supported object according to the obtained operating force. This moves the supported object within the range in which the device can support it, as if the supported object were being moved by an operation by the operator directly, with almost no burden on the operator to support the load, and a detailed explanation is omitted here.

When an assisting force (operating force) in the direction of movement is applied to the care recipient 80, who is suspended and supported by the lifting mechanism 11, through the caregiver 90's assisting operation to move the care recipient 80 up and down, the power assist control by the control unit 14 calculates the assisting force applied to the care recipient 80 by the caregiver 90 by subtracting the load equivalent to the weight of the care recipient 80, which was acquired in advance, from the total load detected by the sensor 12, and operates the actuator 11b of the lifting mechanism 11 according to the obtained assisting force, tilting the arm 11a up or down to move the care recipient 80.

In detail, as a power assist control, when the detected value of the total load resulting from the addition of the assisting force (upward: negative load, downward: positive load) due to the assisting operation to the reference value of the load based on the weight of the care recipient 80 shows a difference that exceeds a preset threshold, for example ±19.6 N (±2 kgf), the control unit 14 activates the actuator 11b of the lifting mechanism 11 to raise or lower the care recipient 80, thereby realizing a reduction in the burden on the caregiver 90 by power assisting the up and down movement of the care recipient 80.

When the difference between the load detection value obtained from the sensor output signal and the reference value exceeds a threshold value during power assist control and the lifting mechanism 11 is to be activated, the control unit 14 calculates and determines the amount of movement (assistance amount) of the care recipient 80 depending on the magnitude of the difference between the load detection value and the reference value, and activates the lifting mechanism 11 accordingly to move the care recipient 80. The control unit 14 also obtains the rate of increase/decrease in the output signal from the sensor 12 and determines the speed of movement based on this.

In power assist control, the control unit 14 monitors changes in the load output value detected by the sensor 12, and does not recognize large load changes in a short period of time that exceed a predetermined rate of change as transient irregular changes caused by the assisting force of the caregiver 90; it only activates the lifting mechanism 11 in response to appropriate load changes.

In addition, the control unit 14 detects a change in load using the sensor 12, determines a difference between the detected load and the reference value that exceeds a threshold, and sets a predetermined waiting time (e.g., 1 second) before activating the lifting mechanism 11. Only when the load change exceeds the threshold and continues to differ from the reference value for at least the waiting time does the control unit 14 determine that the load change is appropriate due to the assisting force of the caregiver 90 and executes control to activate the lifting mechanism 11. This allows for the exclusion of momentary, transient load changes, such as impacts at the start of operation, and allows for the load change due to the assisting force to be correctly determined and the lifting mechanism 11 to be appropriately activated. Furthermore, by determining the load state after the load change has reached a stable state that continues for the waiting time, it is less likely that the assisting force will be erroneously determined, and the lifting mechanism 11 can be appropriately activated based on the load change due to the assisting force.

Furthermore, when the control unit 14 first receives an operation input to the automatic control switch 13a of the operation unit 13 to move the care recipient 80 from the first care appliance to the second care appliance, it operates the lifting mechanism 11 in the upward movement control mode for the care recipient 80 positioned on the first care appliance, automatically raising the sling 50 carrying the care recipient 80, and then interrupts the operation of the lifting mechanism one or more times during the ascent to temporarily suspend the ascent while continuing to lift the care recipient 80, until the care recipient 80 is separated from the first care appliance and the ascent is stopped. After this upward movement control mode, the control unit 14 transitions to power assist control.

Furthermore, when the control unit 14 receives an operation input to the automatic control switch 13a of the operation unit 13 in the power assist control state and the care recipient 80 has moved above the second care appliance, the control unit 14 initiates control in the downward movement control mode. In this downward movement control mode, the care recipient 80 is allowed to descend using a type of power assist control that corresponds to the downward assist force applied to the care recipient 80. When the load detected by the sensor 12 decreases to a predetermined value as the care recipient 80 continues to descend, the control unit 14 operates the lifting mechanism 11 to automatically lower the care recipient 80 without relying on the assist force, and then stops the operation of the lifting mechanism 11, performing a series of controls until the care recipient 80 is supported by the second care appliance.

In addition, while the control unit 14 does not normally perform power assist control when the care recipient 80 is automatically raised or lowered in the upward movement control mode or downward movement control mode, it can also perform similar control based on the load continuously detected by the sensor 12. For example, when the care recipient 80 is automatically raised in the upward movement control mode, if the caregiver 90 applies an upward assisting force and the assisting force is equal to or greater than a preset load value, the control unit 14 can increase the speed of the ascent within a safe range. When the care recipient 80 is automatically lowered in the downward movement control mode, if the caregiver 90 applies a downward assisting force and the assisting force is equal to or greater than a preset load value, the control unit 14 can increase the speed of the descent within a safe range. Conversely, when the care recipient 80 is automatically raised in the upward movement control mode, if the caregiver 90 applies a downward assisting force, the control unit 14 can decrease the speed of the ascent. When the care recipient 80 is automatically lowered in the downward movement control mode, if the caregiver 90 applies an upward assisting force, the control unit 14 can decrease the speed of the descent.

In addition, when the control unit 14 switches to the upward movement control mode or downward movement control mode control state by operating the automatic control switch 13a, or when it is in the power assist control state, a display unit such as a lamp indicating the control state may be provided in a position on the lift device that is easily visible to the caregiver 90, such as the tip of the arm, or the lift device may be configured to have an audio output unit that indicates the start and end of the control state with a buzzer or voice.

Next, the operating state of the lift device according to this embodiment will be described. As a premise, the lift device 1 is assumed to have a built-in battery or be connected to a commercial power source, and to be in a state in which the actuator 11b of the lifting mechanism 11 can be operated by the control unit 14 without any problems in response to operations by the caregiver or other personnel or a pre-set procedure, thereby smoothly raising and lowering the supported care recipient 80. Furthermore, the lift device 1 is assumed to be applied to a travel process for a care recipient 80 receiving specific care, in which the first care appliance serving as the source (starting point of the travel) is a bed 60, and the second care appliance serving as the destination (end point of the travel) is a wheelchair 70.

When moving a care recipient 80 from a bed 60, which is the first care device, to a wheelchair 70, which is the second care device, a procedure is required in which the care recipient 80 supported on the bed 60 is transitioned to a state in which it is supported by the lift device 1, the care recipient 80 is then moved together with the lift device 1 from near the bed 60 to near the destination wheelchair 70, and the care recipient 80 is then transitioned from being supported by the lift device 1 to being supported by the wheelchair 70.

When the care recipient 80 is raised from the bed 60 (the first care device) and supported by the lift device 1, the caregiver 90 first passes the sheet-like sling 50 under the care recipient 80, who is lying supine on the bed 60, so that the sling 50 can support the back of the thighs and back, and the strings at the ends of the sling 50 appear next to the care recipient 80's body and can be hooked onto both ends of the hanger portion 11c of the lifting mechanism 11.

The caregiver 90 then holds the handle 10c and moves the entire lift device until the hanger portion 11c at the tip of the arm 11a is positioned directly above the care recipient 80, and if necessary, until the tip of the base portion 10a of the main frame 10 is positioned below the bed 60. Also, if necessary, the caregiver operates the up switch 13b or down switch 13c of the operating unit 13 to adjust the height of the hanger portion 11c so that the sling 50 can be hung on the hanger portion 11c.

The caregiver 90 hooks the string at the end of the sling 50 onto the end of the hanger part 11c above the care recipient 80, and when preparations for lifting are complete, the caregiver 90 operates the automatic control switch 13a on the operating unit 13.

The control unit 14 receives the first operational input to the automatic control switch 13a during this movement opportunity and initiates control of the upward movement control mode (see Figure 5), activates the actuator 11b of the lifting mechanism 11, and tilts the arm 11a upward. The tilting arm 11a gradually moves the end of the sling 50 hanging from the hanger portion 11c upward, tensioning the loosened sling 50. The care recipient 80, who is supported from below by the now-tensioned sling 50, is then lifted up along with the sling 50 and automatically moved upward little by little (see Figure 3).

As the care recipient 80 supported by the sling 50 rises and the weight of the care recipient 80 gradually transitions from being supported by the bed 60 to being supported by the sling 50, the weight of the sling 50 is applied via the hanger portion 11c, and the load detected by the sensor 12 at the tip of the arm 11a increases.

If, while moving the care recipient 80 upward in this manner, the caregiver 90 notices a problem that would arise if the movement were to continue, such as the care recipient 80 not being properly supported by the sling 50, the caregiver 90 operates the automatic control switch 13a. In response to this operation input to the automatic control switch 13a, the control unit 14 temporarily stops the operation of the actuator 11b of the lifting mechanism 11, stopping the movement of the care recipient 80, and then operates the actuator 11b of the lifting mechanism 11 in the opposite direction, tilting the arm 11a downward, lowering the care recipient 80 and returning it to its initial state before the movement, and terminating control of the upward movement control mode.

When the load detected by the sensor 12 reaches a predetermined stop reference value, for example, 294 N (30 kgf), while the care recipient 80 is being moved upward, the control unit 14 interrupts the operation of the actuator 11b of the lifting mechanism 11, temporarily suspending the lifting of the care recipient 80.

In this paused state, the caregiver 90 can check whether the care recipient 80 is properly supported by the sling 50 and, if necessary, perform operations such as decompression to correct the situation. At this time, if the care recipient 80 has risen sufficiently above the bed 60 and is in a position where the orientation of the care recipient 80 together with the hanger portion 11c and the sling 50 can be changed, it is desirable to change the orientation of the care recipient 80 and place their legs next to the bed 60.

When the caregiver 90 operates the automatic control switch 13a again after completing tasks such as checking on the care recipient 80, the control unit 14 receives this operation input to the automatic control switch 13a, restarts the operation of the actuator 11b, releases the paused movement, and restarts the lifting of the care recipient 80.

If, after this lifting has resumed, the caregiver 90 discovers that continuing the care recipient 80's movement would pose a problem while moving the care recipient 80 upward, the caregiver 90 operates the automatic control switch 13a. In response to this operation input to the automatic control switch 13a, the control unit 14 interrupts the operation of the actuator 11b of the lifting mechanism 11, temporarily halting the movement of the care recipient 80 and allowing the caregiver 90 to make adjustments to the support state of the care recipient 80. Once the care recipient 80 is in a state where there are no problems with its movement, the caregiver 90 can operate the automatic control switch 13a again. In response to this operation input to the automatic control switch 13a, the control unit 14 resumes the operation of the actuator 11b, cancels the paused movement, and resumes the lifting of the care recipient 80.

Furthermore, if, while moving the cared person 80 upward after the lifting has resumed, a situation arises in which there is a problem not only with the movement of the cared person 80 but also with the continued state of the cared person 80 not being supported by the bed 60, when the caregiver 90 operates the lowering switch 13c, the control unit 14 will cease control of the upward movement control mode, temporarily stop the operation of the actuator 11b of the lifting mechanism 11, and then operate the actuator 11b in the reverse direction based on the input to the lowering switch 13c, tilting the arm 11a downward and returning the cared person 80 to the initial state of lying supine on the bed 60 before the movement.

As a general rule, the caregiver 90 does not need to operate the operating unit 13 during the process of the care recipient 80 ascending, which includes pause periods. This allows the caregiver 90 to concentrate on assisting the care recipient 80 in moving. This eliminates the need to assist the care recipient 80 by holding and operating a remote switch in their hand, as is the case with conventional lift devices. They can use both hands to assist the moving care recipient 80 (see Figure 4). This makes it easier to deal flexibly with any abnormal situations and provides the care recipient 80 with a sense of security.

As the sling 50 and care recipient 80 continue to rise, the load detected by the sensor 12 no longer changes even after a predetermined waiting time has elapsed, and the care recipient 80 can be considered to have completely left the top surface of the bed 60. Then, the control unit 14 determines that the upward movement is complete and ends control of the upward movement control mode.

At the same time, the control unit 14 starts power assist control (see Figure 6) and, in the initial stage, recognizes and records the load detection value at this time as the weight of the care recipient 80. The control unit 14 can also display the weight value thus obtained, or the weight value of the care recipient 80 derived from the load detected by the sensor 12 at a different time, on a specified display means provided in the lift device.

Then, the control unit 14 sets the weight value of the certified care recipient 80 as the control reference value, and then activates the lifting mechanism 11 under power assist control.
In the power assist control state, when an assisting force is applied to the care recipient 80 in the moving direction due to a direct assisting operation by the caregiver 90 for moving the care recipient 80 in the up and down direction, the control unit 14 calculates the assisting force applied to the care recipient 80 by the caregiver 90 by subtracting a load equivalent to the weight of the care recipient 80, which is set as a reference value, from the total load detected by the sensor 12. Then, when the difference between the detected load value and the reference value exceeds a threshold value, i.e., when the assisting force is greater than the threshold range, the control unit 14 activates the actuator 11b of the lifting mechanism 11 in accordance with the obtained assisting force to move the arm 11a up and down, thereby realizing the movement of the care recipient 80 with almost no weight support burden on the caregiver 90, in a state where the care recipient 80 moves as if the caregiver 90 were directly operating the care recipient 80 to move it.

Under this power assist control state, the caregiver 90 adjusts the suspension height of the care recipient 80, who has left the bed 60, for example by directly pushing up or down, and then holds the handle 10c of the lift device 1 to operate it, moving the entire lift device together with the suspended care recipient 80 to the destination, i.e., near the wheelchair 70, which serves as the second care equipment.

After movement, when the care recipient 80 supported by the lift device 1 needs to be lowered into the wheelchair 70, the caregiver 90 first adjusts the position of the lift device 1 so that the care recipient 80 is positioned directly above the wheelchair 70. When the caregiver 90 then operates the automatic control switch 13a, the control unit 14 receives the operation input to the automatic control switch and newly starts control in the downward movement control mode (see Figures 9 and 10).

In the downward movement control mode, the initial downward movement of the care recipient 80 is controlled in the same way as power assist control. When the caregiver 90 applies a sufficient amount of downward assist force to the care recipient 80 supported by the sling 50, either directly or via the hanger portion 11c, the control unit 14 detects this and activates the actuator 11b to tilt the arm 11a downward. This adjusts the height position of the care recipient 80, bringing the care recipient 80 closer to the seat of the wheelchair 70 (see Figure 7).

In the downward movement control mode, when the care recipient 80 moves downward and part of their body comes into contact with the seat of the wheelchair 70, with part of the care recipient 80's weight being supported by the wheelchair 70, when the caregiver 90 stops applying assisting force, for example by removing their hand from the care recipient 80, the load detected by the sensor 12 is smaller than before the movement. However, in this downward movement control mode, if the caregiver 90 no longer applies a downward assisting force and the load detected by the sensor 12 does not change for a predetermined waiting time (e.g., one second), the control unit 14 sets the reference value for power assist control to the load at that time. Therefore, even if the detected load value becomes smaller than before, the control unit 14 will not erroneously determine that an upward assisting force has been applied. Instead, the lifting mechanism 11 can be activated in response to subsequent downward assisting forces applied directly or indirectly by the caregiver 90 to the care recipient 80, allowing the care recipient 80 to continue moving downward.

As the care recipient 80 moves downward, the degree to which the care recipient 80 is supported by the wheelchair 70 through the lift device gradually increases. When the load detected by the sensor 12 decreases to a predetermined descent reference value, for example, 49 N (5 kgf), the control unit 14 terminates control to operate the lifting mechanism 11 according to the assisting force, and transitions to an automatic descent control state in which the actuator 11 b is activated to tilt the arm 11 a downward regardless of the presence or absence of assisting force from the caregiver 90, gradually moving the care recipient 80 downward.

If, while the care recipient 80 is being automatically moved downward in this manner, the caregiver 90 notices that continuing the movement of the care recipient 80 would pose a problem, the caregiver 90 operates the automatic control switch 13a, which causes the control unit 14 to temporarily stop the operation of the actuator 11b of the lifting mechanism 11, then operate the actuator 11b in the opposite direction, tilting the arm 11a upward and returning the care recipient 80 to a position away from the seat of the wheelchair 70. When the conditions around the care recipient 80 improve and there are no problems with movement, the caregiver 90 operates the automatic control switch 13a again, which resumes control of the downward movement control mode by the control unit 14. The control unit 14 then activates the actuator 11b of the lifting mechanism 11 in response to the downward assisting force applied by the caregiver 90, causing the care recipient 80 to move downward in the same manner as described above. When the care recipient 80 comes into contact with the seat of the wheelchair 70 and the load detected by the sensor 12 decreases to the predetermined amount, the system will transition to a state in which the care recipient 80 is automatically moved downward in the same manner as described above.

Furthermore, if, during the process of automatically moving the care recipient 80 downward, a situation arises in which there is a problem not only with the movement of the care recipient 80 but also with the continued contact with the wheelchair 70, when the caregiver 90 operates the lift switch 13b, the control unit 14 will cease control of the downward movement control mode, temporarily stop the operation of the actuator 11b of the lifting mechanism 11, and then operate the actuator 11b in the reverse direction, tilting the arm 11a upward and returning the care recipient 80 to the position above the wheelchair 70 that it was in before the movement in the downward movement control mode.

As the state of gradually moving the care recipient 80 downward as an automatic descent continues, the care recipient 80 is completely supported by the wheelchair 70 (see Figure 8), the load detected by the sensor 12 becomes almost zero, and if this state is maintained after a predetermined waiting time has elapsed, the control unit 14 determines that the care recipient 80 has completed moving, stops the operation of the actuator 11b for the automatic descent control, and ends the downward movement control mode.

After the control unit 14 stops operating the actuator 11b, the caregiver 90 removes the string of the sling 50 from the hanger part 11c above the care recipient 80 supported by the wheelchair 70, releasing the care recipient 80 from the lift device 1. The caregiver 90 then operates the lift switch 13b on the operation unit 13 to raise the hanger part 11c as needed, and then moves the entire lift device 1 so that it does not interfere with work on the care recipient 80 in the wheelchair 70, and then removes the sling 50 remaining below the care recipient 80, allowing the care recipient 80 to be moved in the wheelchair 70.

In the upward movement control mode controlled by the control unit 14, the load stop reference value for temporarily suspending the ascent of the care recipient 80 is set to 294 N (30 kgf) as an example. However, this stop reference value can be set to a value adjusted in accordance with the pre-detected weight of the care recipient 80. For example, the stop reference value can be set to a value smaller than 294 N for a lighter care recipient 80, and to a value larger than 294 N for a heavier care recipient 80, so that the degree of lift of the care recipient 80 from the first care appliance, such as a bed, when the ascent of the care recipient 80 is stopped is uniform for all care recipients 80. In this case, it is possible to avoid a situation in which the workload of the caregiver 90 on the care recipient 80 when the care recipient 80 is temporarily suspended varies significantly for each care recipient 80, further reducing the burden on the caregiver 90 in assisting the care recipient 90 with movement.

In this way, when the lift device according to this embodiment assists the care recipient 80 in moving from the bed 60, which is the first care device, to the wheelchair 70, which is the second care device, the control unit 14 first operates in the upward movement control mode, and raises the care recipient 80 supported on the bed 60 by operating the lifting mechanism 11. The lifting of the care recipient 80 continues after a single pause. When the care recipient 80 reaches a state where it is properly supported by the lift device alone, the control unit 14 switches to the power assist control mode, and moves the care recipient 80 above the wheelchair 70 under power assist control. Then, the control unit 14 The system then switches to a downward movement control mode, allowing the care recipient 80 to descend toward the wheelchair 70 with the assistance of the caregiver 90. When the care recipient 80 is partially supported by the wheelchair 70 and the load supported by the lifting mechanism 11 decreases by a predetermined percentage, the system switches to an automatic lowering mode, allowing the care recipient 80 to descend further until the care recipient 80 is supported solely by the wheelchair 70. This eliminates the need for the caregiver or other person to use some kind of operating means on the mechanism in parallel with the movement of the care recipient 80 to operate the lifting mechanism 11, which moves the care recipient 80 up and down.

As a result, during the process of lifting the care recipient 80 from the bed 60 until the power assist control state is reached, in which the caregiver can directly move the care recipient 80 up and down with minimal effort with the assistance of the lifting mechanism 11, and during the process of moving the care recipient 80 from the power assist control state to the destination wheelchair 70, the caregiver 90 can assist with the movement of the care recipient 80 without having to operate the lifting mechanism 11 at the same time.This means that in various situations where assistance is required for the movement of the care recipient 80, the caregiver 90 can concentrate on providing assistance, such as by placing both hands on the care recipient 80, and safety is ensured during the movement of the care recipient 80.

In addition, by temporarily stopping the lifting of the care recipient 80 from the bed 60 (the first care device) and preventing the care recipient 80 from moving, the caregiver 90 is given an opportunity to work on the care recipient 80 and their surroundings without causing any disruption. During this temporary stop, the caregiver 90 can address any issues that have become apparent during the movement of the care recipient 80 in the sling 50, such as entanglement of clothing or twisting of the sling, or perform tasks such as changing the care recipient's position to distribute body pressure or releasing pressure. This prevents the care recipient 80 from continuing to be moved while in an inappropriate state, which could have a negative impact on the care recipient 80.

(Second embodiment of the present invention)
In the lift device of the first embodiment, the configuration is adapted to be applied when a care recipient 80 is moved from a first care device to a second care device, with the first care device being a bed 60 and the second care device being a wheelchair 70. However, this is not limited to this, and in a second embodiment, as shown in Figures 11 and 12, the lift device can also be adapted to be applied to movement when the first care device is a wheelchair 70 and the second care device is a bed 60.

The following describes how the care recipient 80 is moved from the wheelchair 70 to the bed 60 using the lift device according to this embodiment. As a premise, like the first embodiment, the lift device 1 has a built-in battery or is connected to a commercial power source, and the control unit 14 operates the actuator 11b of the lifting mechanism 11 without any problems in response to operations by the caregiver or other personnel or a preset procedure, allowing the supported care recipient 80 to be raised or lowered without difficulty.

When moving a care recipient 80 from a wheelchair 70, which is the first care device, to a bed 60, which is the second care device, a procedure is required in which the care recipient 80 supported on the wheelchair 70 is transitioned to a state in which it is supported by the lift device 1, the care recipient 80 is then moved together with the lift device 1 from near the wheelchair 70 to near the destination bed 60, and the care recipient 80 is then transitioned from being supported by the lift device 1 to being supported by the bed 60.

When the care recipient 80 is moved from the wheelchair 70 and supported by the lift device 1, the caregiver 90 first passes the sheet-like sling 50 under the care recipient 80, who is seated in the wheelchair 70, so that the sling 50 can support the back side of the body from the back to the back of the thighs, and the strings at the ends of the sling 50 appear next to the care recipient's 80 body so that they can be hooked onto both ends of the hanger portion 11c of the lifting mechanism 11.

The caregiver 90 then holds the handle 10c to move the entire lift device, adjusting the position of the lift device 1 so that the hanger portion 11c at the tip of the arm 11a is positioned directly above the care recipient 80. Furthermore, the caregiver 90 operates the up switch 13b or the down switch 13c on the operating unit 13 as necessary to adjust the height of the hanger portion 11c so that the sling 50 can be hung on the hanger portion 11c.

The caregiver 90 hooks the string at the end of the sling 50 onto the end of the hanger part 11c above the care recipient 80, and when preparations for lifting are complete, the caregiver 90 operates the automatic control switch 13a on the operating unit 13.

The control unit 14 receives the first operational input to the automatic control switch 13a during this movement opportunity, and activates the actuator 11b of the lifting mechanism 11 to tilt the arm 11a upward as control of the upward movement control mode. The tilting arm 11a gradually moves the end of the sling 50 hanging from the hanger portion 11c upward, tensioning the loosened sling 50. The care recipient 80, who is supported from below by the now-tensioned sling 50, is then lifted up along with the sling 50 and gradually moved upward.

As the care recipient 80 supported by the sling 50 rises and transitions from a state in which the weight of the care recipient 80 is supported by the wheelchair 70 to a state in which the weight of the care recipient 80 is supported by the sling 50, the load of the sling 50 is applied via the hanger portion 11c, and the load detected by the sensor 12 at the tip of the arm 11a increases.

If, while moving the care recipient 80 upward in this manner, the caregiver 90 notices a problem that would arise if the movement were to continue, such as the care recipient 80 not being properly supported by the sling 50, the caregiver 90 operates the automatic control switch 13a, which causes the control unit 14 to interrupt control of the upward movement control mode and operate the actuator 11b of the hoisting mechanism 11 in the reverse direction, returning the care recipient 80 to the initial state before movement in which they were supported by the wheelchair 70.

While the cared person 80 is being moved upward, when the load detected by the sensor 12 reaches a predetermined stop reference value, for example, 294 N (30 kgf), the control unit 14 interrupts the operation of the actuator 11b of the lifting mechanism 11 and temporarily suspends the lifting of the cared person 80.
This pause allows the caregiver 90 to check whether the care recipient 80 is properly supported by the sling 50 and make corrections if necessary.

When the caregiver 90 operates the automatic control switch 13a again after completing tasks such as checking on the care recipient 80, the control unit 14 receives the operation input to the automatic control switch 13a and resumes operation of the actuator 11b, causing the care recipient 80 to begin rising again.

If, after this lifting resumes, the caregiver 90 discovers a new problem with continuing the care recipient 80's movement while moving the care recipient 80 upward, the caregiver 90 operates the automatic control switch 13a. As in the first embodiment, the control unit 14 receives the operation input to the automatic control switch 13a and interrupts the operation of the actuator 11b of the lifting mechanism 11, temporarily halting the movement of the care recipient 80, allowing the caregiver 90 to make adjustments to the support state of the care recipient 80, etc. Once the caregiver 90 has achieved a condition in which the care recipient 80's movement is not problematic, the caregiver 90 can operate the automatic control switch 13a again. Once the care recipient 80 is in a state where there are no problems with its movement, the caregiver 90 can operate the automatic control switch 13a again. The control unit 14 receives the operation input to the automatic control switch 13a and resumes the operation of the actuator 11b, canceling the paused movement and restarting the lifting of the care recipient 80.

Furthermore, if, during the process of moving the care recipient 80 upward after the lifting has resumed, a situation arises in which there is a problem not only with the movement of the care recipient 80 but also with the continued state of the care recipient 80 not being supported by the wheelchair 70, when the caregiver 90 operates the lowering switch 13c, the control unit 14 will cease control of the upward movement control mode, temporarily stop the operation of the actuator 11b of the lifting mechanism 11, and then operate the actuator 11b in the opposite direction, tilting the arm 11a downward and returning the care recipient 80 to the initial state of sitting in the wheelchair 70 before movement.

As with the first embodiment, the caregiver 90 does not, in principle, need to operate the operating unit 13 during the process of the care recipient 80 ascending, including the pause period. This allows the caregiver 90 to concentrate on assisting the care recipient 80 in moving. This eliminates the need to assist the care recipient 80 by holding and operating a remote switch in their hand, as is the case with conventional lift devices. They can use both hands to assist the moving care recipient 80 (see Figure 11). This makes it easier to deal flexibly with any abnormal situations and provides the care recipient 80 with a sense of security.

As the sling 50 and care recipient 80 continue to rise, the load detected by the sensor 12 no longer changes even after a predetermined waiting time has elapsed, and the care recipient 80 can be considered to have completely left the seat of the wheelchair 70. Then, the control unit 14 determines that upward movement is complete and ends control of the upward movement control mode.

At the same time, the control unit 14 starts power assist control, and in the initial stage, it recognizes and records the load detection value at this point as the weight of the care recipient 80. The control unit 14 then sets the recognized weight value of the care recipient 80 as the control reference value, and then operates the lifting mechanism 11 under power assist control.

In the power assist control state, as in the first embodiment, when the caregiver 90 directly assists the care recipient 80 by moving the care recipient 80 up and down, applying an assisting force in the direction of movement to the care recipient 80, the control unit 14 calculates the assisting force applied by the caregiver 90 from the total load detected by the sensor 12. If the assisting force exceeds a threshold range, the control unit 14 activates the lifting mechanism 11 in accordance with this assisting force, thereby realizing movement of the care recipient 80 as if the caregiver 90 were directly moving the care recipient 80. In this power assist control state, the caregiver 90 adjusts the suspension height of the care recipient 80, who has left the wheelchair 70, for example, by directly pushing up or down, and then operates the handle 10c of the lift device 1 to move the entire lift device together with the suspended care recipient 80 to the desired location.

After movement, when the care recipient 80 supported by the lift device 1 needs to be lowered onto the bed 60, the caregiver 90 first moves the lift device 1 close to the bed 60, and then adjusts the position of the lift device 1 as necessary, such as by moving it until the tip of the base portion 10a of the main frame 10 is under the bed 60 so that at least the upper part of the care recipient 80's body above the thighs is positioned above the bed 60. When the caregiver 90 then operates the automatic control switch 13a, the control unit 14 receives the operation input to the automatic control switch and newly starts control in the downward movement control mode.

In the downward movement control mode, the initial downward movement of the care recipient 80 is controlled in the same way as power assist control. When the caregiver 90 applies a sufficient amount of downward assist force to the care recipient 80 supported by the sling 50, either directly or via the hanger portion 11c, the control unit 14 detects this and activates the actuator 11b to tilt the arm 11a downward, thereby adjusting the height position of the care recipient 80 and bringing the care recipient 80 closer to the top surface of the bed 60 (see Figure 12).

In the downward movement control mode, when the care recipient 80 moves downward and comes into contact with the upper surface of the bed 60, with part of their weight being supported by the bed 60, the load detected by the sensor 12 becomes smaller than before the movement when the caregiver 90 stops applying an assisting force, for example by removing their hands from the care recipient 80. However, in this downward movement control mode, if the caregiver 90 no longer applies a downward assisting force and the load detected by the sensor 12 does not change for a predetermined waiting time (e.g., one second), the control unit 14 updates the reference value for the power assist control to the load at that time. This prevents the control unit 14 from erroneously determining that an upward assisting force has been applied even if the detected load value becomes smaller than before. Instead, the lifting mechanism 11 is activated in response to subsequent downward assisting forces applied directly or indirectly by the caregiver 90 to the care recipient 80, allowing the care recipient 80 to continue moving downward.

When the care recipient 80 has moved downwards to the point where they are in contact with the top surface of the bed 60, it is desirable for the caregiver 90 to change the orientation of the care recipient 80 together with the hanger portion 11c and the sling 50, so that the entire body of the care recipient 80, including their legs, is positioned on the bed 60.

As the care recipient 80 moves downward, the degree to which the care recipient 80 is supported by the bed 60 through the lift device 1 gradually increases. When the load detected by the sensor 12 decreases to a predetermined lowering reference value, for example, 49 N (5 kgf), the control unit 14 terminates control to operate the lifting mechanism 11 in accordance with the assisting force, and transitions to a control state in which the care recipient 80 is automatically lowered by activating the actuator 11 b to tilt the arm 11 a downward regardless of whether or not the caregiver 90 is applying assisting force, gradually moving the care recipient 80 downward.

If, while the care recipient 80 is being automatically moved downward in this manner, the caregiver 90 notices that continuing the movement of the care recipient 80 would pose a problem, the caregiver 90 operates the automatic control switch 13a, which causes the control unit 14 to temporarily stop the operation of the actuator 11b of the lifting mechanism 11, then operate the actuator 11b in the opposite direction, tilting the arm 11a upward and returning the care recipient 80 to a position away from the top surface of the bed 60. When the conditions around the care recipient 80 improve and there are no problems with movement, the caregiver 90 operates the automatic control switch 13a again, which resumes control of the downward movement control mode by the control unit 14. The control unit 14 then activates the actuator 11b of the lifting mechanism 11 in response to the downward assisting force applied by the caregiver 90, causing the care recipient 80 to move downward in the same manner as described above. When the care recipient 80 comes into contact with the upper surface of the bed 60 and the load detected by the sensor 12 decreases to the predetermined amount, the system will transition to a state in which the care recipient 80 is automatically moved downward in the same manner as described above.

Furthermore, if, during the process of automatically moving the care recipient 80 downward, a situation arises in which there is a problem not only with the movement of the care recipient 80 but also with the continued contact with the bed 60, when the caregiver 90 operates the lift switch 13b, the control unit 14 will cease control of the downward movement control mode, temporarily stop the operation of the actuator 11b of the lifting mechanism 11, and then operate the actuator 11b in the reverse direction, tilting the arm 11a upward and returning the care recipient 80 to the position above the bed 60 that it was in before the movement in the downward movement control mode.

As the state of gradually moving the care recipient 80 downward as an automatic lowering continues, the care recipient 80 is completely supported by the bed 60, the load detected by the sensor 12 becomes nearly zero, and if this state is maintained after a predetermined waiting time has elapsed, the control unit 14 determines that the movement of the care recipient 80 has been completed, stops the operation of the actuator 11b related to the automatic lowering control, and ends the downward movement control mode.

After the control unit 14 stops operating the actuator 11b, the caregiver 90 removes the string of the sling 50 from the hanger part 11c above the care recipient 80 who has landed on the bed 60, releasing the care recipient 80 from the lift device 1. The caregiver 90 then operates the lift switch 13b on the operation unit 13 to raise the hanger part 11c as needed, and then moves the entire lift device 1 so that it does not interfere with work on the care recipient 80 who is placed on the bed 60, and then removes the sling 50 remaining below the care recipient 80, allowing the care recipient 80 to lie supine on the bed 60.

In this way, even when the care recipient 80 moves from the wheelchair 70 (the first care device) to the bed 60 (the second care device), the lift device of this embodiment operates in the upward movement control mode, where the control unit 14 operates the lifting mechanism 11 to raise the care recipient 80 supported on the wheelchair 70, pausing once before continuing to raise the care recipient 80. Once the care recipient 80 is properly supported by the lift device alone, the control unit 14 switches to the power assist control mode and moves the care recipient 80 above the bed 60 under power assist control. After that, the control unit 14 switches to the downward movement control mode, where the care recipient 80 is allowed to descend toward the bed 60 with the assistance of the caregiver 90. The control unit 14 then switches to the automatic lowering mode, where the care recipient 80 is further lowered until the care recipient 80 is supported by the bed 60 alone, eliminating the need for the caregiver or other person to operate any operating means in parallel with the up and down movement of the care recipient 80.

As a result, during the process of lifting the care recipient 80 from the wheelchair 70 until the power assist control state is reached where the care recipient 90 can directly move the care recipient 80 up and down with the assistance of the lifting mechanism 11, and during the process of moving the care recipient 80 from the power assist control state to the bed 60, the care recipient 90 can assist with the movement of the care recipient 80 without having to operate the lifting mechanism 11 at the same time.In various situations where assistance is required for the movement of the care recipient 80, the care recipient 90 can assume an assisting position with both hands on the care recipient 80, allowing them to concentrate on providing assistance and ensuring safety during the movement of the care recipient 80.

(Third embodiment of the present invention)
In the lift device according to the first embodiment, the control unit 14 is configured to automatically start the power assist control including measuring the body weight and setting the reference value of the body weight following the control of the upward movement control mode when the control of the upward movement control mode ends. However, this is not limited to this, and as a third embodiment, as shown in Figures 13 and 14, a power assist switch 13d may be provided to instruct the control unit 14 to start the power assist control, and the control unit 14 may start the power assist control based on the operation of the power assist switch 13d by a caregiver or the like at any timing after the upward movement control mode ends.

Specifically, as the lifting device 50 and care recipient 80 continue to rise in the upward movement control mode, the load detected by the sensor 12 no longer changes even after a predetermined waiting time has elapsed, and the care recipient 80 can be considered to have completely left the top surface of the bed 60. The control unit 14 then terminates control of the upward movement control mode, but unlike the first embodiment, it does not automatically start power assist control, and instead leaves the lifting mechanism 11 operable, waiting for operation by a caregiver or the like.

Until the power assist switch 13d is operated, the system will not transition to a new control state and will maintain the state in which the care recipient 80 is positioned above the bed. The caregiver 90 can then move the care recipient 80 together with the sling 50 and hanger portion 11c to change their orientation relative to the arm 11a, or operate the up switch 13b or down switch 13c on the operating portion 13 to activate the lifting mechanism 11 and move the care recipient 80 up or down to adjust its position.

After adjusting the position and orientation of the care recipient 80 as necessary, the caregiver 90 operates the power assist switch 13d. In response to this operation input to the power assist switch 13d, the control unit 14 starts power assist control (see Figure 14), recognizes and records the load detection value at the start of this control as the weight of the care recipient 80, and sets this weight value as the reference value for control.

After this, as in the first embodiment, in the power assist control state, when the caregiver 90 directly assists the care recipient 80 by moving the care recipient 80 up and down, applying an assisting force in the direction of movement, the control unit 14 calculates the assisting force applied by the caregiver 90 from the total load detected by the sensor 12, and if the assisting force exceeds the threshold range, it activates the lifting mechanism 11 in accordance with this assisting force, thereby realizing movement of the care recipient 80 in a state in which the care recipient 80 moves as if the caregiver 90 were directly moving the care recipient 80.

When the control unit 14 ends control of the upward movement control mode, depending on the characteristics of the first care appliance, for example, the repulsive force of the bed, the amount of load detected by the sensor 12 may remain constant and not change even when the care recipient 80 has not completely left the top surface of the care appliance, causing the control unit 14 to end control of the upward movement control mode.

In this way, if the control of the upward movement control mode ends before the care recipient 80 has completely left the top surface of the care appliance and the control unit 14 then starts power assist control as in the first embodiment, for example, the control unit 14 may mistake the sudden change in the load detection value at the moment the care recipient 80 is moved and completely removed from the top surface of the care appliance as the application of an assist force, resulting in a situation where the lifting mechanism 11 unintentionally moves the care recipient 80, requiring the caregiver 90 to perform complex tasks to return the device to a state where it is responding to the caregiver's original movement assistance operations.

In response to this, by having the control unit 14 initiate power assist control based on the operation of the power assist switch 13d, it is possible to provide an opportunity for the caregiver 90 to perform preparatory work by operating the lifting switch 13b, etc., to adjust the care recipient 80 until they are completely clear of the top surface of the device, before operating the power assist switch 13d to transition the control unit 14 to the power assist control state. In this way, by having the caregiver perform the necessary work before operating the power assist switch 13d, once power assist control is initiated by the subsequent operation of the power assist switch 13d, the caregiver 90 can smoothly and easily assist the care recipient 80 in moving the device with the assistance of the lifting mechanism 11.

(Fourth embodiment of the present invention)
In the lift device of the first embodiment, the control unit 14, in the upward movement control mode, operates the lifting mechanism 11 to raise the sling 50 carrying the cared person 80, and interrupts the operation of the lifting mechanism 11 to temporarily suspend the lifting once to ensure that the caregiver 90 can perform tasks such as adjusting the support state of the cared person 80 by the sling 50. Once a condition is achieved where there are no problems with the movement of the cared person 80, the control unit 14 operates the lifting mechanism 11 in response to the operation of the caregiver 90, and resumes the lifting of the cared person 80. However, without being limited to this, the control unit 14 can also be configured to interrupt the operation of the lifting mechanism 11 to temporarily suspend the lifting multiple times while raising the cared person 80 in the upward movement control mode.

Furthermore, when the control unit resumes the lifting of the care recipient 80 from a paused state, the configuration is not limited to one in which the control unit 14 controls the lifting to resume after receiving an operational input from the automatic control switch 13a. As shown in FIG. 15, the control unit 14 can also be configured to monitor changes in load detected by the sensor 12 while in a paused state, and automatically operate the lifting mechanism 11 to resume the lifting of the care recipient 80 when it determines that a transition has occurred to a state in which no changes in load are occurring, which indicates that the caregiver 90 has finished their work. In other words, this control means that the control unit 14 maintains the paused state of the lifting of the care recipient in the upward movement control mode while a change in load associated with the caregiver performing a specified care assistance task is detected by a detection means such as a sensor.

This section explains the control of the upward movement control mode of the control unit in this embodiment. Movements by controls other than the upward movement control mode are the same as in the first embodiment, and so explanations will be omitted.

When the caregiver 90 operates the automatic control switch 13a of the operation unit 13 when preparations are complete to lift the care recipient 80, the control unit 14, similar to the previous embodiment, receives the operation input to the automatic control switch 13a and operates the actuator 11b of the lifting mechanism 11 to tilt the arm 11a upward as control of the upward movement control mode (see Figure 15). The tilting arm 11a gradually moves the end of the sling 50 hanging from the hanger portion 11c upward, tensioning the sling 50 that was previously loose.

When the sling 50 is in a tensed state, the load based on the weight of the care recipient 80 is transmitted to the arm 11a via the sling 50 and hanger portion 11c, and the load detected by the sensor 12 at the end of the arm gradually increases.

Under these circumstances, when the load detected by the sensor 12 reaches a preset first stop reference value, for example, 49 to 98 N (5 to 10 kgf), the control unit 14 stops the operation of the actuator 11b of the lifting mechanism 11, temporarily suspending the lifting of the care recipient 80.

In this paused state, the caregiver 90 can check that the string at the end of the sling 50 is properly fastened to the hanger portion 11c, that there are no problems such as the string becoming entangled around the care recipient 80, and make any necessary corrections.

After the temporary suspension, the control unit 14 monitors, based on the load detection output from the sensor 12, whether a load change has occurred due to vibrations or the like caused by the caregiver 90 working on the lifting device 50 or the care recipient 80, and continues to temporarily suspend the lifting mechanism 11 while the caregiver 90 is working and a load change is occurring.

Then, when the control unit 14 determines that no change in the load has occurred for a predetermined waiting time, i.e., that the caregiver 90 has not been performing any work for the waiting time, it determines that the caregiver 90 has finished working, and resumes operation of the actuator 11b of the lifting mechanism 11, causing the lifting of the care recipient 80 to begin again.

After this ascent resumes, the tilting of arm 11a causes the care recipient 80 supported by the sling 50 to rise, and the weight of the care recipient 80 gradually transitions from being supported by the bed 60 or wheelchair 70 to being supported by the sling 50, causing the load detected by sensor 12 to increase. When the load detected by sensor 12 reaches a preset second stop reference value, for example, 294 N (30 kgf), the control unit 14 again stops the operation of actuator 11b of the lifting mechanism 11, temporarily suspending the ascent of the care recipient 80.

During this second pause, the caregiver 90 can check whether the care recipient 80 is properly supported by the sling 50 without any bias, whether the seat portion of the sling 50 is properly in contact with the caregiver's body, etc., and make any necessary corrections.

Even during this second pause, the control unit 14 monitors, based on the load detection output from the sensor 12, whether a load change has occurred due to vibrations or the like caused by the caregiver 90 performing work on the lifting device 50 or the care recipient 80, and maintains the paused state of the lifting mechanism 11 while a load change occurs due to the caregiver 90 performing some work.

Then, when the control unit 14 determines that the caregiver 90 continues not to perform any work and that no change in the load has occurred over the waiting time, it determines that the caregiver 90 has finished working, resumes operation of the actuator 11b of the lifting mechanism 11, and the lifting of the care recipient 80 begins anew.

After this, as in the first embodiment, the lifting of the sling 50 and the care recipient 80 continues, and eventually, when the load detected by the sensor 12 stops changing for a predetermined time and the care recipient 80 can be considered to have left the top surface of the bed 60 or the wheelchair 70, the control unit 14 determines that the movement is complete and ends control in the upward movement control mode.

If, after resuming ascent after each temporary suspension, the caregiver 90 determines that there is a problem with continuing the movement of the care recipient 80 while moving the care recipient 80 upward and operates the automatic control switch 13a or the lowering switch 13c, as in the above embodiment, the control unit 14 may receive the operation input and interrupt the operation of the actuator 11b of the lifting mechanism 11, temporarily stopping the movement of the care recipient 80. Of these, if the automatic control switch 13a is operated, the control unit will maintain the temporary suspension state until the caregiver 90 operates the automatic control switch 13a again. After operating the automatic control switch again, the control unit will resume the operation of the actuator 11b, cancel the temporary suspension of the movement, and resume the ascent related to the care recipient 80 getting out of bed. On the other hand, when the lowering switch 13c is operated, the upward movement control mode is stopped and the control unit 14 operates the actuator 11b in the reverse direction, returning the care recipient 80 to the initial state before movement, in which they are supported by the bed 60 or wheelchair 70.

Fifth Embodiment of the Present Invention
In the lift device according to the first embodiment, when the caregiver 90 operates the automatic control switch 13a during power assist control, the control unit 14 receives an operation input to this automatic control switch 13a and uniformly switches to the downward movement control mode. However, in addition to this, if the control unit is in the power assist control state and the caregiver is not assisting the care recipient and the lifting mechanism is not operating, and an operation input is received to the automatic control switch, the control unit switches to the downward movement control mode. On the other hand, if the control unit is in the same power assist control state and receives an operation input to the automatic control switch while the lifting mechanism is operating to move the care recipient, the control unit can temporarily stop the power assist control, and after acquiring and setting a new load equivalent to the weight of the care recipient as the reference value for the load used to calculate the assist force, resume the power assist control.

In this case, when moving under power assist control, for example, if the care recipient is already positioned above the second care appliance and no further movement is required other than lowering the care recipient, the caregiver can operate the automatic control switch at the desired timing to transition the control unit to downward movement control mode, allowing the care recipient to be moved smoothly and quickly to the second care appliance.

Furthermore, if an incorrect reference value is set, for example, because the caregiver's assist force for manipulating the care recipient is recognized as part of the care recipient's static load, and the control unit erroneously determines that an assist force is being applied due to the discrepancy between the incorrect reference value and the true load when the caregiver is not performing any movement assistance operations, and activates the lifting mechanism, causing the care recipient to move inappropriately, the caregiver can immediately interrupt power assist control by operating the automatic control switch, thereby eliminating the incorrect load reference value set by the control unit, making it easier to ensure the accuracy and safety of the care recipient's movement under power assist control. In addition, there is no need to provide a separate operating means such as a switch to stop power assist control and then restart it after normalization, thereby reducing the cost of the device.

While the lift device in each of the above embodiments is a movable floor-traveling type, it is not limited to this. As long as it can move a care recipient suspended and supported by a lifting mechanism such as an arm from the first care appliance to the second care appliance, it can be a device that moves the entire main frame, such as the floor-traveling type described above. It can also be a fixed-installation lift device in which the main frame consists of a movable part and a fixed part, and the movable part of the main frame equipped with the lifting mechanism is moved or rotated within a movable range relative to the fixed part of the main frame to move the care recipient horizontally. For example, it can be a free-standing lift device in which the fixed part of the main frame is fixed to the bedside, etc., or a ceiling-traveling lift device in which the fixed part of the main frame is installed on the ceiling and the movable part of the main frame slides relative to this fixed part.

REFERENCE SIGNS LIST 1 Lift device 10 Main body frame 10a Base 10b Standing part 10c Handle 11 Lifting mechanism 11a Arm 11b Actuator 11c Hanger part 12 Sensor 13 Operation part 13a Automatic control switch 13b Ascending switch 13c Descending switch 13d Power assist switch 14 Control part 50 Lifting tool 60 Bed 70 Wheelchair 80 Care recipient 90 Caregiver

Claims (4)

A care lift device comprising: a main body frame; a lifting mechanism provided on the main body frame for suspending and lowering a lifting device carrying a care recipient; a detection means for detecting a load applied to the lifting mechanism; and a control unit for controlling the operation of the lifting mechanism, wherein the control unit is capable of executing power assist control to determine the assisting force applied to the care recipient from the caregiver based on the load detected by the detection means and to operate the lifting mechanism in accordance with the obtained assisting force, thereby enabling the care recipient to be moved from a predetermined first care appliance to a second care appliance;
An operation unit having one or more switches, including at least an automatic control switch that gives a predetermined control instruction to the control unit,
The control unit
When an initial operation input is received by the automatic control switch, the upward movement control mode is set to operate the lifting mechanism for the care recipient positioned on the first care appliance, raising the sling carrying the care recipient, and interrupting the operation of the lifting mechanism one or more times during the raising to temporarily suspend the raising, while continuing to raise the care recipient;
When the load detected by the detection means does not increase or change for a predetermined time due to the transition of the care recipient from the first care implement due to the lifting, the lifting mechanism stops lifting the lifting tool, the upward movement control mode is terminated, and the lifting mechanism is transitioned to the power assist control state automatically or in response to an operation input to a predetermined switch,
When a new operation input is received to the automatic control switch in the power assist control state, the system switches to a downward movement control mode, allowing the care recipient to descend by power assist control according to the downward assist force applied to the care recipient, and further, when the load detected by the detection means decreases to a predetermined value as the care recipient continues to descend, the system switches to a state in which the lifting mechanism is activated to automatically lower the care recipient without relying on the assist force;
A lift device characterized in that, when the load detected by the detection means does not decrease or change for a predetermined period of time as the care recipient transitions to a state where he or she is supported by the second care device due to descent, the operation of the lifting mechanism is stopped and the downward movement control mode is terminated. 2. The lift device according to claim 1,
The lift device is characterized in that the control unit temporarily suspends the lifting of the care recipient in the upward movement control mode when the load detection value of the detection means reaches a predetermined reference value. 3. The lift device according to claim 2,
The control unit sets a reference value of the load detection value relating to the timing to temporarily suspend the lifting of the care recipient in the upward movement control mode based on a weight of the care recipient detected in advance. 4. The lift device according to claim 1,
The control unit is configured to transition to a downward movement control mode when the control unit receives an operation input to the automatic control switch while the control unit is in a power assist control state and the caregiver is not performing any assistance operation on the care recipient and the lifting mechanism is not operating.