JPH06121813A - Lift for seat of wheel chair - Google Patents

Abstract

PURPOSE:To enable the operating of an operation lever simply with a smaller size and a less weight of a wheel chair by arranging a switching lever to be interlocked through a switching pawl and a spring while making a spindle turn only in one way alternately and the operation level for turning the spindle to get a chain looped on sprocket wheels. CONSTITUTION:A pair of chains 31 and 31 with the upper end thereof put around the upper part of a rear surface of an upright frame 1 is inserted through a spindle 20 while being looped on sprockets 23, 27 and 18 positioned on the rear surface of the frame 1, the lower end of the chain 31 is mounted on a lower frame 3 through a spring 32 and the sprockets 23, 27 and 18 are always kept meshed with the chains 31 and 31 looped thereon by the weight of a seat 9. The sprockets are checked with the meshing between a worm 25 and a worm wheel 26 even when being forced to turn under the weight of the seat 9 and the seat 9 is halted at a arbitrary position. This allows a physically handicapped person to operate an operation lever 46 by himself through a clutch mechanism to accomplish a lifting or lowering of the seat 9 in safety.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a seat lifting device in a wheelchair for a physically handicapped person, especially a person with a lower limb disability.

[0002]

2. Description of the Related Art Wheelchairs are necessary for people with physical disabilities to carry out their daily lives in the same manner as ordinary people, and for that purpose vertical movement of the seat is essential. However, since the vertical movement of the seat in this type of conventional wheelchair uses a battery, the weight increases and the size increases, and it is almost impossible to use in a general home.

In order to solve the above-mentioned problems, the applicant of the present application considers that the wheelchair is to be used indoors in a fully manual manner, makes the wheelchair as small and lightweight as possible, and makes it possible to easily operate the operation lever. We have already proposed and devised a lifting device for a seat in a wheelchair that improves workability and safety (Actual publication 6
No. 1-1288).

The seat lifting device for a wheelchair according to the above proposal has been very well received by wheelchair users and is still widely used. It goes without saying that the operation of the above device itself is good, but since the device uses a screw brake mechanism, if the screw part becomes dirty or the oil runs out, the brake will not work or the seat will There was a problem of instability of the lifting and lowering operation of the seat, that is, it did not go up even when trying to raise it, or it dropped too much when lowering it.

[0005]

SUMMARY OF THE INVENTION The present invention has been invented in view of the above-mentioned problems, and in consideration of using it indoors in a fully manual manner, the wheelchair is made as small and lightweight as possible,
(EN) Provided is a seat lifting device for a wheelchair, which completely solves the above-mentioned instability of the seat lifting operation, without impairing the advantage of the conventional device that can easily operate the operation lever to improve workability and safety. The purpose is to

[0006]

In order to solve the above problems, in a seat lifting device of a wheelchair according to the present invention, a pair of standing frames having a pair of casters at the front and a pair of running wheels at the rear. A seat mounted on the front side of the standing frame so as to be able to move up and down, an upper end attached to an upper part on the back side of each standing frame, and a lower end attached to a lower end portion of the standing frame via a spring. A pair of chains, a pair of mounting plates respectively mounted on the back side of the seat, and a main shaft horizontally supported by the mounting plates,
A first bevel gear mounted on the main shaft, a first sprocket wheel integrally provided with the first bevel gear, a second bevel gear meshing with the first bevel gear, and the second bevel gear. A worm provided coaxially with the worm, a worm wheel meshing with the worm, a second sprocket wheel integrally provided with the worm wheel, and a fixed sprocket provided above the first sprocket wheel. A shuttle wheel, a switching ratchet rotatably attached to the other end of the spindle that penetrates through the mounting plate, a switching pawl that appropriately interlocks with the switching ratchet, a switching pawl and a spring that are interlocked via a spring, It has a switching lever that alternately rotates only in one direction and an operation lever that rotates the main shaft, and the chain is wound around each sprocket wheel.

According to the present invention, a person with a disability can operate the operation lever himself to safely move the seat up and down.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings. In FIG. 1, a pair of standing frames 1 is provided. The lower portion of the standing frame 1 becomes a vertical portion 1a,
The upper portion of the standing frame 1 is inclined to the back side to form an inclined portion 1b.

A tip of an upper frame 2 whose rear portion is connected slightly above the vertical portion 1a of the standing frame 1 and a tip of a lower frame 3 which is connected to a lower end of the standing frame are connected by a connecting portion 4, and this connecting portion is connected. A caster 5 is rotatably supported on the lower end of the shaft 4. A step pipe 6 on which a foot is placed is rotatably attached in front of the connecting portion 4.

Numeral 7 is a shaft supporting portion provided on the back side of the substantially middle portion of each standing frame 1, and a wheel 8 for traveling is rotatably supported on the shaft supporting portion 7. Reference numeral 10 denotes a square seat plate. Back seat pipes 11 and 11 are attached to the rear portion of the seat plate in the vertical direction, and handrail pipes 12 and 12 are attached to both sides of the seat plate 10 to form the seat plate 9. I am doing it.

Reference numerals 13 and 13 are located on the outer side of each standing frame 1, and are attached to upper portions of the backrest pipes 11 and 11 so as to be located below the standing frames, rearward, that is, on the side opposite to the seat plate. Is.

Located above the mounting plates 13, 13,
Moreover, the spacer 15 is inserted through the mounting shaft 14 which is positioned on the front side of the standing frame 1 and supported horizontally.
The pair of rollers 16, 16 abutted on the front surface of each standing frame 1 are rotatably supported at substantially opposite ends of the vertical frame 5.

At both ends of a fixed shaft 17 which is rotatably mounted on the inside of the mounting plates 13 and 13 and on the rear upper side of the standing frame 1, the standing frames 1 and 1 are provided.
A pair of fixed sprockets 1 that are attached to the back of each
A main shaft 20 having shafts 8 and 18 positioned below the fixed shaft 17 is rotatably supported via bearings to bosses fixed inside the mounting plates 13 and 13, respectively. Has one end penetrating one mounting plate 13.

A first bevel gear 22 is mounted on the main shaft 20. A first sprocket wheel 23 is integrally provided on the first bevel gear 22. The first bevel gear 2
The tooth surface of the second bevel gear 24 meshes with the tooth surface of 2.

A worm 25 is coaxially provided on the second bevel gear 24. A worm wheel 26 meshes with the worm 25. The worm wheel 26 is integrally provided with a second sprocket wheel 27.

The worm 25 is provided with a torque limiter (not shown) for preventing breakage, and is constructed so as to idle when it rotates too much and not break when it goes to the upper and lower ends. 28 is a bearing for the shaft 25a of the worm 25.

These sprockets 23, 27 and 18 are located on the respective back sides of the standing frame 1 and are used to circulate the chain 31 respectively. The tip of the chain 31 is fixed to the upper back surface of each standing frame 1, and these sprockets 23, 27, 18 are circulated, and the chain 3
The lower ends of 1, 31 are connected to the lower frames 3, 3 via springs 32, 32, respectively.

Reference numeral 33 is a roller support piece mounted so as to project to the lower rear surface side of each backrest pipe 11, and both ends of a shaft 14a pivotally supported by this support piece are paired with the rollers 16 to form a pair of rollers of the standing frame 1. Roller 3 that rollably contacts the front side
4 is pivotally supported and is positioned between both rollers, and a spacer is inserted through the shaft 14a.

Main shaft 2 protruding outward from one mounting plate 13
A switching ratchet 35 and a case 36 are fixed to the tip of 0, and a switching claw 37 that is switchably engaged with a tooth portion 35a of the switching ratchet 35 is pivotally supported on the case 36 by a shaft 38.

An opening 39 provided on one side of the case 36
The base 41 of the lever 40 that is switched outward from the base is attached to the case 36 by the shaft 42, and the first stopper 43 and the second stopper 44 that engage with the base 41 are attached to the base 4.
1 is attached to the case 36 at appropriate intervals on both sides.

The base 41 of the switching lever 40 and the switching claw 3
7 is linked by a spring 45, and an operating lever 46 is fixed to the tip of the case 36. In the case 36, the main shaft 20
A clutch mechanism for switching the rotation direction of the main shaft 20 by the switching lever 40 is built in, and the main shaft 20 can be rotated and idle by operating the operation lever 46.
In the figure, 47 and 47 are handle parts for the caregiver provided on the upper rear surface side of the standing frame 1, and 48 is a key.

Next, the operation of this embodiment will be described.
A pair of chains 31, 31 whose upper ends are wound around the upper part of the rear surface of the standing frame 1 are inserted into the main shaft 20 and are located on the rear surface of the standing frame 1 in the respective sprockets 23, 27, 18.
The lower end of the chain 31 is attached to the lower frame 3 via a spring 32, and the sprockets 23, 27, 18 are always meshed with the rotated chains 31, 31 due to the weight of the seat 9, and the arrow shown in FIG. Power is working in the A direction.

Depending on the weight of the seat 9, the sprocket 23,
Even if 27 and 18 try to rotate, they are stopped by the engagement of the worm 25 and the worm wheel 26, and the seat 9 is stopped at an arbitrary position.

The case of lowering the seat 9 will be described. As shown by the solid line in FIG. 2, when the switching lever 40 is moved about the shaft 42 until one side of the base 41 is locked to the first stopper 43, the spring 45 is moved. Switching claw 3 via
The left end of 7 engages with the tooth portion 35a of the switching ratchet 35,
As a result, when the operation lever 46 is rotated in the direction of arrow X in FIG. 2, the main shaft 20 rotates together with the switching ratchet 35, and when the operation lever 46 is rotated in the direction of arrow Y, the switching claw 37 idles. 20 does not rotate.

Therefore, when the operation lever 46 is moved up and down in FIG. 1, the main shaft 20 rotates and the seat 9 descends only when it is moved up (direction of arrow X). In this way, by operating the operation lever 46, the seat 9 can be lowered to a predetermined position.

Thus, the vertical portion 1 is provided below the standing frame 1.
There is a, and the upper part of this vertical part is provided with the inclined part 1b which is inclined slightly rearward, so that when the seat 9 descends to the lower end, the seat plate 10 becomes horizontal so as to be in close contact with the floor. . Further, when the seat is at a certain height or higher and is positioned on the slope 1b, the seat has an angle that rises forward and is easy to sit.

Next, the case of raising the seat 9 will be described. First, as shown by the alternate long and short dash line in FIG. 2, the switching lever 40 is operated until one side of the base 41 is locked to the second stopper 44.
When is rotated to switch, the right end of the switching claw 37 engages with the tooth portion 35a of the switching ratchet 35 via the spring 45, and as a result, when the operating lever 46 is rotated in the arrow Y direction in FIG. The switching ratchet 35 and the main shaft 20 rotate, and when the operating lever 46 rotates in the arrow X direction, the switching claw 37 idles and the switching ratchet 35 and the main shaft 20 do not rotate.

Therefore, in FIG. 1, when the operating lever 46 is moved up and down, the main shaft 20 rotates and the seat 9 is raised only when it is moved down, that is, when it is moved in the Y direction.

In this case, due to the weight and load of the seat 9,
Even if an attempt is made to rotate the main shaft 20 in the direction of the arrow X, the seat 9 does not descend because it is stopped by the mesh of the worm 25 and the worm wheel 26. The operation lever 46 is shown in FIG.
Even when the switching piece 37 is rotated in the direction of the arrow X in FIG. 2, the switching piece 37 idles and the switching ratchet 35 and the main shaft 20 do not rotate at all.

【The invention's effect】

As described above, according to the present invention, a person with a disability can operate the operating lever by himself / herself through the clutch mechanism, so that the seat can be lifted / lowered safely. Since it can be operated and does not require any drive source and can be operated manually, it has an advantageous feature that the overall size and weight can be reduced and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is an overall side view showing an embodiment of the present invention.

FIG. 2 is a cross-sectional explanatory view showing a relationship between an operation lever and a spindle.

FIG. 3 is an explanatory diagram showing a main part of a chain drive mechanism.

[Explanation of symbols]

 1 Stand frame 9 Seat 11 Back pipe 13 Mounting plate 20 Spindle 22, 24 Bevel gear 23, 27, 18 Sprockets 25 Worm 26 Worm wheel 31 Chain

Claims (1)

[Claims] 1. A pair of standing frames having a pair of casters on the front side and a pair of running wheels on the rear side, a seat mounted on the front side of the standing frames so as to be able to move up and down, and a rear surface of each standing frame. A pair of chains each having an upper end attached to the upper part of the side and a lower end attached to the lower end of the upright frame via a spring, a pair of attachment plates attached to the rear side of the seat, and the attachment plate. A main shaft horizontally supported on the mounting plate, a first bevel gear mounted on the mounting plate, a first sprocket wheel integrally provided with the first bevel gear, and a first mesh gear meshing with the first bevel gear. A double bevel gear, a worm coaxially provided with the second bevel gear, a worm wheel meshing with the worm, a second sprocket wheel integrally provided with the worm wheel, and the first sprocket Tutofoil Via a fixed sprocket wheel provided above, a switching ratchet pivotally attached to the other end of the main shaft through which the mounting plate penetrates, a switching pawl that is properly combined with the switching ratchet, and the switching pawl and a spring. Characterized in that it has a switching lever that interlocks with each other and alternately rotates the main shaft only in one direction, and an operation lever that rotates the main shaft, and that the chain is attached to each sprocket wheel by being rotated. Lifting device for a seat in a wheelchair.