JP2000288032A - Wheelchair - Google Patents

Abstract

PROBLEM TO BE SOLVED: To move a wheelchair over a large step by requiring nearly no force. SOLUTION: Rear side auxiliary wheels 6A and 6B are arranged in the rear part of main wheels 3A and 3B. The wheels 6A and 6B are moved to storage positions being higher than the ground contact surface of the main wheels 3A and 3B when a wheelchair is travelled by an air cylinder 7. When it is moved up onto the step, the wheels 6A and 6B are moved to progress positions being lower than the storage positions by the air cylinder 7 to lift-up the main wheels 3A and 3B. Besides, chains 8 for transmitting the rotation of the wheels 3A and 3B to the wheels 6A and 6B is also arranged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wheelchair, and more particularly to an improvement in the structure of a wheelchair capable of easily raising a step on a running road surface.

[0002]

2. Description of the Related Art In recent years, slopes have been provided in various public facilities and the like in order to enable movement by a wheelchair. However, in general urban areas, there are steps on sidewalks and the like. Since a small auxiliary wheel is provided in front of the wheel, there is a problem that it is not possible to climb a step by itself. In order to solve this problem, for example, in JP-A-9-572 or JP-A-11-28232, an auxiliary wheel is further provided behind the main wheel, and the auxiliary wheel is supported by a contractible damper or the like. Wheelchairs have been proposed.

[0003] In such a wheelchair, when the occupant applies weight backward when coming near a step, the damper is contracted in accordance with this load, and the entire wheelchair leans rearward. The ring rises. Then, the raised front auxiliary wheel is lowered onto the step, and then the wheelchair is raised on the step by rotating the large-diameter main wheel while returning the weight forward.

[0004]

However, in the above-mentioned conventional wheelchair, a relatively large force is required to rotate the main wheel and raise the wheelchair onto the step, so that a non-powered occupant goes up the step. In addition, when the main wheels are electrically driven, there is a problem that the drive motor becomes unnecessarily large. In this case, if the repulsion / extension force of the damper or the like is set to be large, the force required when climbing up the step is reduced, but the contraction amount of the damper when the occupant applies weight backward becomes small. The amount of backward inclination of the wheelchair is reduced, and as a result, the elevation of the front auxiliary wheels is suppressed, and it is still difficult to climb a large step.

[0005] Therefore, the present invention is to solve such a problem, and an object of the present invention is to provide a wheelchair which can go up a large step with almost no force.

[0006]

In order to achieve the above object, according to the present invention, a main wheel (3A, 3B) and a front auxiliary wheel (4) are provided.
A, 4B) in a wheelchair traveling while supporting the chair (1), behind the main wheels (3A, 3B), the rear auxiliary wheels (6).
A, 6B) and rear auxiliary wheels (6A, 6B).
B) is moved to a storage position above the grounding surface of the main wheels (3A, 3B) during traveling, or to an advanced position below the storage position to lift the main wheels (3A, 3B). An auxiliary wheel moving means (7) is provided, and the main wheels (3A, 3A) are provided.
A rotation transmitting means (8) for transmitting the rotation of B) to the rear auxiliary wheels (6A, 6B) is provided.

[0007] In the present invention, when a step appears on the front of the road surface, the occupant in the seating chair applies weight backward. When the center of gravity of the occupant moves rearward, the wheelchair tilts rearward until the rear auxiliary wheel in the stowed position touches the ground, and accordingly the front auxiliary wheel rises greatly and comes to a position higher than the upper surface of the step. In this state, when the rear auxiliary wheel is moved to a lower advanced position by the rear auxiliary wheel moving means, the rear auxiliary wheel is already in contact with the ground, so that the main wheel is located at the front auxiliary wheel as a fulcrum and is higher than the upper surface of the step. It is pushed up to a high position. Therefore, when the main wheel is rotated, the rear auxiliary wheel is also rotated in the same direction by the rotation transmitting means, and the wheelchair is advanced by the front and rear auxiliary wheels in the step direction, and the main wheel is raised on the step.
Thereafter, the rear auxiliary wheel is moved up to the storage position again by the rear auxiliary wheel moving means.

As described above, the rear auxiliary wheel is moved downward by the rear auxiliary wheel moving means, and the main wheel is relatively lifted. In this state, the main wheel is moved to the step by the front and rear auxiliary wheels. Therefore, it is possible to smoothly climb a high step with almost no force.

The reference numerals in parentheses indicate the correspondence with the specific means described in the embodiments described later.

[0010]

FIG. 1 shows the appearance of a wheelchair. In the drawing, a seat chair 1 made of a sheet material having an L shape in a side view is supported on both sides by pipe frames 2A and 2B. Large-diameter main wheels 3A and 3B are rotatably mounted on the left and right pipe frames 2A and 2B, respectively, and small-diameter front auxiliary wheels 4A and 4B are provided in front of the main wheels 3A and 3B.
Are arranged. Seat chair 1 is left and right pipe frame 2
The vehicle travels on a road surface supported by the main wheels 3A and 3B and front auxiliary wheels 4A and 4B provided at the front and rear positions of A and 2B.

A support arm 5 extends rearward from the left and right pipe frames 2A and 2B, and the left and right support arms 5 are integrated by a cross member (not shown) extending in the width direction. The base end of each support arm 5 is a main wheel 3A, 3B
Are rotatably connected to the rotary shaft of
The rear auxiliary wheels 6A and 6B of small diameter are rotatably mounted at the front end of. Tip of support arm 5 and pipe frame 2
An air cylinder 7 (only one is shown) is disposed between the air cylinder A and the air cylinder 7A. A base end of the air cylinder 7 is connected to the pipe frames 2A and 2B, and a piston rod 71 protruding from the air cylinder 7 is provided. Is coupled to the distal end of the support arm 5.

The piston rod 71 is urged in the retreating direction by a spring provided in the air cylinder 7, and in the state shown in which the piston rod 71 is retracted, the support arm 5 is moved upward from a road surface. The rear auxiliary wheels 6A, 6B provided at the tips are located at a storage position above the grounding surfaces of the main wheels 3A, 3B. Also, the rear auxiliary wheel 6
A, 6B and the main wheels 3A, 3B
1 are connected by a chain 8 via a sprocket (not shown) provided on the vehicle 1. When the main wheels 3A, 3B are rotated, the rear auxiliary wheels 6A, 6B also rotate integrally therewith.

An air pump 9 is provided below the front end of the pipe frame 2A.
1 is connected to the tip of the operation piece 92. The operation piece 92 extends from the base end of the rod-shaped pump handle 10, and the base end of the pump handle 10 is rotatably connected to a horizontal support shaft 101 provided on the pipe frame 2A. The tip of the pump handle 10 extending above the chair 1 is a handle 102
When the occupant grips the handle portion 102 and reciprocates the pump handle 10 back and forth, the operating rod 91 of the air pump 9 is moved back and forth, and the air hose pipe 9
3 supplies compressed air to the air cylinder 7;
The piston rod 71 is advanced.

When the piston rod 71 is advanced, the support arm 5 rotates downward, and the rear auxiliary wheels 6A and 6B are lowered and moved to the advanced position described later. An air bleeding valve 11 is provided in the upper part of the front end of the pipe frame 2A. The air bleeding valve 11 is interposed in the air hose pipe. When the operation knob 111 is operated, the compressed air supplied to the air cylinder 7 is supplied. Is exhausted, and the piston rod 71 retreats into the air cylinder 7. Thus, the support arm 5 is rotated upward again, and the rear auxiliary wheels 6A and 6B are returned to the upper storage position.

In the wheelchair having such a structure, when a step S appears in front of the road surface as shown in FIG. 2, the occupant in the seating chair applies weight to the rear. As the occupant's center of gravity moves rearward, the wheelchair tilts rearward until the rear auxiliary wheel 6A in the stowed position comes into contact with the ground, as shown in FIG. 3, and the front auxiliary wheel 4A rises significantly with this. It comes to a position higher than the upper surface of the step S. In this state, the main wheel 3A is rotated to approach the step S, and the front auxiliary wheel 4A is positioned above the step S as shown in FIG.

Subsequently, when the compressed air is supplied to the air cylinder 7 by reciprocating the pump handle 10 back and forth, the support arm 5 rotates downward with the extension of the piston rod 71, and the rear auxiliary wheel 6A is moved. It descends and moves to the advance position,
Since the rear auxiliary wheel 6A is already in contact with the ground, the main wheel 3A is pushed up to a position higher than the upper surface of the step S with the front auxiliary wheel 4A as a fulcrum as shown in FIG. In this state, the main wheel 3A
When the wheelchair is rotated in the direction of the arrow in FIG. 5, the rear auxiliary wheel 6A is also rotated in the same direction by the chain 8, and the wheelchair advances in the step S direction supported by the front and rear auxiliary wheels 4A and 6A. The main wheel 3A reaches the step S as shown in FIG. After that, the compressed air in the air cylinder 7 is exhausted by operating the operation knob 111 of the air release valve 11, and the piston rod 71 is retracted into the air cylinder 7 as shown by the chain line in FIG. The support arm 5 is rotated upward to raise the rear auxiliary wheel 6A to the storage position.

As described above, the rear auxiliary wheels 6A, 6B are advanced downward by the air cylinder 7, and the main wheels 3A, 3B are relatively lifted. In this state, the front and rear auxiliary wheels 4A, 4B, 6
Since the main wheels 3A and 3B are moved onto the step S by A and 6B, the high step S can be performed with little force.
Can go up smoothly.

In the above embodiment, a telescopic mechanism such as a hydraulic cylinder or a motor may be used instead of the air cylinder. Further, the main wheels may be manually driven or electrically driven. When the main wheels are electrically driven, the output of the main wheel drive motor may be small, so that the size of the motor can be reduced.

[0019]

As described above, according to the wheelchair of the present invention, a large step can be raised smoothly with almost no force.

[Brief description of the drawings]

FIG. 1 is an overall perspective view of a wheelchair.

FIG. 2 is a schematic side view illustrating the operation of a wheelchair.

FIG. 3 is a schematic side view illustrating the operation of the wheelchair.

FIG. 4 is a schematic side view illustrating the operation of the wheelchair.

FIG. 5 is a schematic side view illustrating the operation of the wheelchair.

FIG. 6 is a schematic side view illustrating the operation of the wheelchair.

[Explanation of symbols]

1 ... seat chair, 2A, 2B ... pipe frame, 3A, 3B
... Main wheels, 4A, 4B ... front auxiliary wheels, 5 ... support arms, 6
A, 6B: rear auxiliary wheel, 7: air cylinder, 8: chain. 9 air pump, 10 pump handle, 11 air release valve.

Claims (1)

[Claims] 1. A wheelchair that travels while supporting a chair with a main wheel and a front auxiliary wheel, wherein a rear auxiliary wheel is provided behind the main wheel, and the main wheel when the rear auxiliary wheel is running. A rear auxiliary wheel moving means for moving the main wheel to the storage position above the ground contact surface or to the advanced position below the storage position to lift the main wheel, and A wheelchair provided with rotation transmitting means for transmitting to a side auxiliary wheel.