GB2583527A - Patient lifting device - Google Patents

Abstract

A patient lifting device comprising first and second side units 12, 14 pivotally or hingedly attached to one another with a seat 52 connected between them. Each unit comprising a base 16, a top bar 48, a scissor linkage 44, interconnecting the base with the top bar, and an electrically powered actuator to move the scissor linkage and thereby adjusting the height of the seat. Optionally each base defines a guide upon which is supported a carriage, which is secured to an inner carriage located within the guide. In an embodiment the actuator comprises an electrically powered motor to drive a threaded rotatable shaft, which is located within the guide. Optionally the seat may comprise a flexible panel and a seat back. Preferably each scissor linkage is an asymmetric form.

Description

PATIENT LIFTING DEVICE

This invention relates to a patient lifting device, and in particular to a lifting device suitable for use in the lifting of an individual from substantially ground level to an elevated level.

Where an individual, for example with impaired mobility, is laying or sitting upon the ground, for example as a result of having fallen over, then there is often a need for a carer or other assistant to help the individual, lifting the individual to, for example, a wheelchair, a seat, a bed or the like. In order to be undertaken safely, lifting an individual in this manner may require two or more carers or assistants. Where only a single carer or assistant is available, this may result in the individual being left sat or laid upon the ground for an extended period of time, which is undesirable. Even where sufficient carers or assistants are available, lifting of an individual in this manner carries the risk of injury to the carer or assistant and, potentially, to the individual. It is an object of the invention to provide a lifting device suitable for use in such applications.

A number of hoist devices are known, which can be used in the lifting or movement of individuals. In these devices, the individual being lifted sits in a sling suspended beneath a hoist lifting arm. However, many individuals find them uncomfortable to use, and the feeling of being suspended beneath a hoist, and potentially swinging a little, results in individuals having concerns over the safety and stability of the equipment. Also, the hoist devices tend to be of large size, and so transportation and storage thereof can be problematic.

One known patient lifting device takes the form of an inflatable cushion that, once positioned beneath the individual, can be inflated to lift the individual from substantially ground level to an elevated position. Again, the individual being lifted often feels poorly supported leading to a lack of confidence in the ability of the device to safely lift them.

As noted hereinbefore, it is an object of the invention to provide a lifting device suitable for use in the lifting of an individual from substantially ground level, in which at least some of the disadvantages associated with known arrangements are overcome or are of reduced effect. A specific objective is to provide a lifting device which is of relatively compact form and so transportation, handling and storage is relatively straightforward.

According to the invention there is provided a lifting device comprising first and second side units pivotally or hingedly connected to one another, each side unit comprising a base, a top bar, a scissor linkage interconnecting the base with the respective top bar, and an electrically powered actuator operable to drive at least part of the scissor linkage for movement and thereby adjust the spacing of the top bar from the base, and a seat connected between the top bars of the first and second side units.

Such a lifting device is of relatively simple form. When not in use, the side units can be positioned adjacent one another and substantially parallel to one another, with the top bars lowered to lie adjacent the respective bases. The lifting device may thus be of relatively compact form. Storage and handling thereof is thus relatively straightforward.

Each base conveniently defines a guide upon which a carriage is located, the carriage being guided and supported for movement along the guide. A first link of the scissor linkage is preferably pivotally mounted upon the base and a second link of the scissor linkage is preferably pivotally mounted upon the carriage. A low friction material element is preferably carried by the carriage, located between the carriage and the guide to aid movement of the carriage.

Each actuator conveniently comprises a rotatable shaft provided with a thread formation, the shaft conveniently being located within the guide, and an electrically powered motor operable to drive the shaft for rotation. An inner carriage is conveniently located within the guide, the inner carriage being secured to the aforementioned carriage, and the inner carriage including a drive element received within the thread formation of the shaft such that rotation of the shaft drives the inner carriage, and hence the aforementioned carriage, for axial or linear movement.

The seat may take the form of a flexible panel secured to the top bars. Alternatively, the seat could be of a rigid form, removably attachable to the top bars. A seat back may be attached to or attachable to the top bars.

The scissor linkage is preferably of asymmetric form.

A sensor is preferably provided, operable to sense whether parts of the lifting device are in contact with the individual. The output of the sensor may be used in the control of the actuators, ceasing operation thereof in the event that it is detected that the individual is touching part of the lifting device, thereby reducing the risk of injury arising from, for example the individuals hands becoming trapped within the scissor linkages.

The invention will further be described, by way of example, with reference to the accompanying drawings, in which: Figures 1 and 2 are perspective views illustrating a lifting device in accordance with an embodiment of the invention; and Figures 3 to 8 are views illustrating parts the lifting device of Figures 1 and 2.

Referring to the accompanying drawings, a lifting device 10 is illustrated for use in lifting an individual from substantially ground level to an elevated position. By way of example, the device 10 may be used in the event that the individual has fallen, and needs to be lifted to allow the individual to be seated upon a chair, moved to a bed or other piece of furniture, or moved to a wheelchair or the like. It will be appreciated that these represent just examples of applications in which the invention may be employed, and that the invention is not restricted in this regard.

The lifting device 10 comprises a pair of side units 12, 14 which are pivotally or hingedly connected to one another. The side units 12, 14 are substantially identical to one another, and so only one of the side units 12, 14 is described herein in further detail.

S The side unit 12 comprises a base 16 which, in use, rests upon the ground. The base 16 comprises an elongate base plate 18 supporting a motor housing 20 and a guide member 22 in the form of a tubular shaft of substantially circular cross sectional shape. The motor housing 20 houses an electrically operated motor 24, an output of which is connected to an elongate drive shaft 26 that is located within the guide member 22. The drive shaft 26 is supported for rotation by bearings 30. The drive shaft 26 is provided, on its outer periphery, with a helical thread formation 32.

Supported upon the drive shaft 26 within the guide member 22 is an inner carriage 34. The inner carriage 34 carries a drive pin 36 that extends generally horizontally, substantially tangentially to the drive shaft 26, the drive pin 36 sitting within the thread formation 32.

An outer carriage 38 is supported upon the exterior of the guide member 22, the outer carriage 38 being secured to the inner carriage 34 by means of bolts 40 which extend through an elongate slot formed in the underside of the guide member 22. The outer carriage 38 is provided with an inner sleeve 42 of a low friction material, the inner sleeve 42 bearing against the outer surface of the guide member 22.

In use, operation of the motor 24 to drive the drive shaft 26 for rotation causes the inner carriage 34, and hence the outer carriage 38, to be driven axially or linearly, with the outer carriage 38 supported by and guided by the guide member 22.

The side unit 12 further comprises a scissor linkage 44 in the form of a pair of link arms 46a, 46b which are pivotally connected to one another in an X-shaped configuration. A lower end of the arm 46a is pivotally connected to the base 16 adjacent the motor housing 20, and a lower end of the other arm 46b is pivotally connected to the outer carriage 38.

The side unit 12 further comprises a top bar 48 which is pivotally connected to the upper end of the arm 46b. The upper end of the other arm 46a is provided with a roller 50 which is able to travel within a channel defined by the top bar 48. As illustrated in Figures 7 and 8, the top bar 48 is shaped to include curved side regions within which domed end parts of the roller 50 are located, the arrangement being such that the roller 50 is held against lateral movement, and so the risk of binding within the channel is reduced.

The scissor linkage 44 is of asymmetric design, the pivotal connection between the arms 46a, 46b being offset from an axis interconnecting the points at which the arm 46a is connected to the base 16 and the roller 50, and from an axis interconnecting the points at which the arm 46b is connected to the outer carriage 38 and the top bar 48.

The bases 16 of the side units 12, 14 are pivotally interconnected, and the top bars 48 of the side units 12, 14 are pivotally interconnected, the pivot axes being substantially coaxial.

A fabric or flexible plastics material seat 52 is connected to the top bars 48, extending therebetween, and a seat back 54 is attachable to the top bars 48. A brace 56 is attachable between the bases 16. It will be appreciated that the interconnection of the top bars 48 by the seat back 54, and of the bases 16 by the brace 56 holds the side units 12, 14 in the required V-shaped configuration, in use, and enhances the rigidity of the lifting device 10.

The lifting device 10 can be stowed in a relatively compact form with the scissor linkages 44 positioned such that each top bar 48 lies immediately above the respective base 16, and with the side units 12, 14 positioned adjacent one another.

In use, in the event that an individual has fallen and requires lifting, the lifting device 10 is positioned close to the individual, and the side units 12, 14 thereof are pivoted apart so that the lifting device adopts a V-shaped form. The brace 56 may be employed to secure the bases 16 to one another in this configuration, and the seat back 54 installed to secure the top bars 48 to one another. In this condition, the seat 52 will rest upon the ground between the top bars 48.

The individual can then be slid or otherwise moved onto the seat 52, and may rest against the seat back 54. Once in this position, the motors 24 are operated. Operation of the motors 24, as described hereinbefore, causes rotation of the drive shaft 26 and linear movement of the inner and outer carriages 34, 38, moving the points at which the arms 46b are pivotally connected to the outer carriages 38 closer to the points at which the arms 46a are pivotally connected to the bases 16. As a consequence of this movement, the scissor linkages 44 operate to lift the top bars 48 away from the bases 16, and so lifting the seat 52 and the individual sat thereon from the ground to a raised or elevated position.

At least part of the individuals weight is borne through the bearing formed by the inner sleeve 42 and is transmitted therefrom through the guide member 22 and remainder of the base 16 to the ground. Accordingly, this load is not transmitted directly to the drive shaft 26 in such a manner as to cause bending or the like thereof.

Once the lifting device 10 has been used to lift the individual to a suitable height, operation of the motors 24 may cease. Limited switches are preferably provided to sense when the scissor linkages 44 reach the ends of their permitted ranges of movement, the outputs of which can be used in controlling the motors 24, the motors 24 ceasing operation upon reaching the ends of their permitted ranges of movement. The motors 24 may be controlled independently, so that in the event of becoming out of synch, they will reset themselves automatically. Friction within the drive train is sufficient that the lifting device 10 will remain in the raised position. The individual may then be transferred to, for example, a wheelchair, a chair, a bed or the like, for example using a transfer board or the like to aid such movement. After the individual has been transferred from the lifting device 10, the device 10 may be returned to its original configuration for transportation or storage.

By providing a scissor linkage 44 of asymmetric form, it will be appreciated that the force required to commence lifting may be reduced.

The lifting device 10 is of relatively simple and convenient form, being convenient to store and to transport. In use, the device 10 is of good stability, and is simple to use. Individuals being lifted, and carers or assistants operating the device 10 may thus have a good degree of confidence in the safety and operability of the device 10. The motors 24 are conveniently controlled by a central control unit which may serve to ensure that both motors 24 operate simultaneously, and that both top bars 48 move at the same rate. However, small differences in the rate of movement need not significantly negatively impact upon the operation or performance of the device 10.

A capacitance sensor or the like may be provided to monitor for human contact with at least some metallic parts of the device 10, the output of the sensor being used by the control unit in controlling operation of the motors 24. In this manner, if the individual being lifted or the carer or assistant operating the device 10 makes contact with, for example, one of the top bars 48 or scissor linkages 44, operation of the motors 24 may cease to reduce the risk of injury through becoming trapped within, for example, parts of the scissor linkages 44.

It will be appreciated that whilst a specific embodiment of the invention is described herein with reference to the accompanying drawings, a wide range of modifications and alterations may be made thereto without departing from the scope of the invention as defined by the appended claims.

Claims (12)

1. CLAIMS: 1. A lifting device comprising first and second side units pivotally or hingedly connected to one another, each side unit comprising a base, a top bar, a scissor linkage interconnecting the base with the respective top bar, and an electrically powered actuator operable to drive at least part of the scissor linkage for movement and thereby adjust the spacing of the top bar from the base, and a seat connected between the top bars of the first and second side units.
2. 2. A device according to Claim 1, wherein each base defines a guide upon which a carriage is located, the carriage being guided and supported for movement along the guide.
3. 3. A device according to Claim 2, wherein a first link of the scissor linkage is pivotally mounted upon the base and a second link of the scissor linkage is pivotally mounted upon the carriage.
4. 4. A device according to Claim 2 or Claim 3, wherein a low friction material element is carried by the carriage, located between the carriage and the guide.
5. 5. A device according to any of Claims 2 to 4, wherein each actuator comprises a rotatable shaft provided with a thread formation.
6. 6. A device according to Claim 5, wherein the shaft is located within the guide.
7. 7. A device according to Claim 5 or Claim 6, wherein the actuator further comprises an electrically powered motor operable to drive the shaft for rotation.
8. 8. A device according to any of Claims 2 to 7, further comprising an inner carriage is located within the guide, the inner carriage being secured to the aforementioned carriage.
9. 9. A device according to Claim 8 when dependent directly or indirectly upon Claim 5, wherein the inner carriage includes a drive element received within the thread formation of the shaft such that rotation of the shaft drives the inner carriage, and hence the aforementioned carriage, for axial or linear movement.
10. 10. A device according to any of the preceding claims, wherein the seat comprises a flexible panel secured to the top bars.
11. 11. A device according to any of the preceding claims, further comprising a seat back attached to or attachable to the top bars.
12. 12. A device according to any of the preceding claims, wherein each scissor linkage is of asymmetric form.