JP2000135247A - Two-wheel caster for wheelchair - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a two-wheel caster for a wheelchair capable of smoothly getting over a traveling floor surface or road surface having a step having a larger height difference than a radius of the front wheel of a front wheel caster. SOLUTION: This device comprises a caster shaft 4 having a stopper 8 protruded at a lower end part to be installed on a front leg frame 3 of a wheelchair, an oscillation support member 5 pivotally installed on a lower end part of the caster shaft 4 at a base end part and having an abutment part 10 to be applied to the stopper 8, a rotary arm 6 rotatably installed on the oscillation support member 5, a front wheel 13 installed on a lower end of the rotary arm 6, and an auxiliary shaft 14 installed on a tip of the oscillation support member 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a two-wheel caster for a wheelchair for the elderly and the disabled.

[0002]

2. Description of the Related Art Elderly and disabled people who have difficulty walking are
In general, a wheelchair is used for the movement. In recent years, the movement performance of wheelchairs has been considerably improved and it has become more comfortable. However, the performance cannot be easily exerted on road surfaces having steps or unevenness.

[0003] That is, since the height over which the wheel of the wheelchair rides is theoretically the radius of the front wheel of the front wheel caster, if the front wheel caster of the wheelchair has a height difference between the stepped portion and the uneven portion which is about the radius of the front wheel. However, there is a problem that traveling on a floor surface or a road surface, which cannot be overcome and has a certain level of height difference in a step portion or an uneven portion, is restricted.

Conventionally, focusing on such problems,
Research has been conducted on the structure of the front wheel casters for wheelchairs so that the wheelchair can travel even if there is a certain level of unevenness or uneven surface.However, not only does the structure of the front wheel casters become complicated, but also the front wheel dimensions and the overall caster The situation was that the weight of the car increased.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned conventional problems, and it is an object of the present invention to provide a traveling floor or road surface having a step having a height difference larger than a radius of a front wheel of a front wheel caster. Even with this, we provide a two-wheel caster that has the same level of ability to get over a step as a large wheel and that can function as a front wheel caster for a compact and lightweight wheelchair, with the ability to easily get over and run smoothly without difficulty. It is to be.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problem, and is a two-wheel caster for a wheelchair which has a function of turning by being attached to a front leg frame of a wheelchair. A swing support having a protruding stopper, a caster shaft for attachment to the front leg frame of the wheelchair, and a contact portion having a base end pivotally connected to a lower end of the caster shaft and abutting on the stopper. A member, a rotating arm rotatably attached to the swing support member, and a front wheel attached to the lower end of the rotating arm and an auxiliary wheel attached to the tip of the swing support member,
An object of the present invention is to provide a wheelchair two-wheel caster having a function of climbing over a step.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described based on embodiments with reference to the drawings. FIG. 1 is an overall view of a wheelchair 2 showing a state in which a two-wheel caster 1 of the present invention is applied to a wheelchair 2. The two-wheel caster 1 according to the present invention is attached to each of the left and right front leg frames 3 and 3 of the wheelchair 2 like the normal front wheel caster 1.

FIG. 2 is a diagram showing a configuration of a main part of the two-wheel caster 1. As shown in FIG. The two-wheel caster 1 includes a caster shaft 4 for attaching to the front leg frame 3 and a swing support member 5.
And a rotating arm 6.

The caster shaft 4 is fixed to and attached to a lower end of the front leg frame 3 of the wheelchair 2 by a suitable fixing means, and a stopper 8 having a downwardly inclined surface 7 protrudes slightly above the lower end. .

The swing support member 5 is bent slightly downward near its base end as shown in FIG.
The contact surface 1 that contacts the stopper 8 on the upper surface of the bending portion 9
0 is formed.

The base end of the swing support member 5 is pivotally connected to the lower end of the caster shaft 4 by a horizontal support shaft 11 and is limited by a stopper 8 around the horizontal support shaft 11. It is rotatable in the pitching direction within the range. That is, when the wheelchair 2 is on the flat floor surface F, the contact surface 10 of the swing support member 5 contacts the lower inclined surface 7 of the stopper 8, and the swing support member 5 is in the state of FIG. . Then, from this state, the swing support member 5 is rotatable counterclockwise about the horizontal support shaft 11.

At the center of the swing support member 5, the upper end of a rotary arm 6 is pivotally connected by a vertical support shaft 12, and the rotary arm 6 is bent backward and downward, and the vertical support shaft is bent. 12 can be rotated in the yaw direction. Thereby, a direction changing function is provided similarly to the front wheel caster of the conventional wheelchair 2. At the lower end of the rotating arm 6, the front wheel 1
The wheelchair 2 has a function as a normal front wheel. The vertical support shaft 12 is located substantially above the front edge E of the front wheel 13. The front wheel 13 normally rolls in contact with the floor surface F or the road surface. An auxiliary wheel 14 is attached to the tip of the swing support member 5.

The operation of the two-wheel caster 1 according to the present invention having the above-described structure will be described. When traveling on a normal flat floor surface F or a road surface, the contact surface 10 of the swing support member 5 is in contact with the lower inclined surface 7 of the stopper 8, and the front wheel 13 is moved in the state of FIG. And rolling on the road surface.

Now, the operation of the wheelchair 2 going over the step D having a height difference with a larger radius than the front wheel 13 arranged on the floor or the road will be described. When the wheelchair 2 moves forward and approaches the stepped portion D, the front edge of the front wheel 13 first contacts the vertical portion 15 of the stepped portion D at a point A as shown in FIG.

Further, when the forward force of the wheelchair 2 (generally generated by the user driving the main wheel 16 by hand) is transmitted to the swing support member 5 through the caster shaft 4, the point A is centered. Then, a counterclockwise moment M1 is generated in the system including the rotating arm 6 and the swing support member 5. As a result, the swing support member 5 rotates counterclockwise about the point A as shown in FIG.
7 contacts point B.

Since the vertical support shaft 12 is positioned so as to be located immediately above the front edge E of the front wheel 13, the front wheel 13 abuts at the point A and the forward force of the wheelchair is further reduced. , The rotating arm 6 moves the vertical support shaft 12
It does not rotate around.

Further, when the forward force is transmitted to the caster shaft 4 by the forward movement of the wheelchair 2, a counterclockwise moment M1 is applied to a system including the swing support member 5, the rotating arm 6 and the front wheel 13 around the point B. Acts, and the swing supporting member 5
Rotate counterclockwise about a point. Thereby, as shown in FIG. 5, the front wheel 13 rises and climbs over the stepped portion D, and contacts the upper surface thereof at the point C. That is, the two-wheel caster 1
As shown in FIG. 5, it is possible to get over the step D.

After climbing over the step D in this way, the wheelchair 2 and a part of the weight W of the user are added downward to the rear end of the swing support member 5 via the caster shaft 4, so that the swing A moment M2 is applied clockwise to the support member 5, and the support member 5 rotates clockwise about the point C. Thereby, as shown in FIG. 6, the auxiliary wheel 14 is lifted upward from the upper surface 17 of the step D until it comes into contact with the stopper 8, and the two-wheel caster 1 returns to the normal running state.

If the two-wheel caster 1 gets over the step D, the radius of the main wheel 16 of the wheelchair 2 is larger than that of the step D, so that the wheel D can be easily moved over the step D by further moving forward. Thus, the vehicle can normally travel on the upper surface 17 of the step D.

In the above embodiment, the case where the two-wheel caster 1 according to the present invention is applied as the front wheel 13 of the wheelchair 2 has been described. However, it is needless to say that the two-wheel caster 1 can be applied to other luggage carrying equipment such as luggage carrying tools.

[0021]

In the two-wheel caster according to the present invention, a rotatable swing support member is provided on a caster shaft, a front wheel is attached to the swing support member, and an auxiliary wheel is attached to a tip portion of the swing support member. Because the momentum is applied to the swing support member by using the forward force of the wheelchair, it can be smoothly and smoothly, even if the floor or road surface has a step with a height difference larger than the radius of the front wheel, or uneven surfaces. The ability to ride over bumps and bumps, that is, running over the road, can be sufficiently exhibited.

Furthermore, the two-wheel caster of the present invention has a very simple and lightweight structure, is inexpensive to manufacture, and can be easily attached to an existing wheelchair. It will make a great contribution to the aging society.

[Brief description of the drawings]

FIG. 1 is a diagram showing a state in which a two-wheel caster according to the present invention is applied to a wheelchair.

FIG. 2 is a view for explaining an embodiment of the two-wheel caster according to the present invention, and is a view showing a normal running state.

FIG. 3 is a view for explaining the operation of the two-wheel caster of the embodiment, and is a view showing a state in which a front wheel is in contact with a step portion.

FIG. 4 is a view for explaining the operation of the two-wheel caster of the embodiment, and is a view showing a state where an auxiliary wheel is in contact with an upper surface of a step portion.

FIG. 5 is a view for explaining the operation of the two-wheel caster of the embodiment, and shows a state in which an auxiliary wheel and a front wheel ride on an upper surface of a step portion D.

FIG. 6 is a view for explaining the operation of the two-wheel caster of the embodiment, and shows a state in which the vehicle has returned to a normal running state after riding on the upper surface of the step portion D.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Two-wheel caster 2 Wheelchair 3 Front leg frame 4 Caster shaft 5 Swing support member 6 Rotating arm 8 Stopper 13 Front wheel 14 Auxiliary wheel 16 Main wheel D Step

[Procedure amendment]

[Submission date] October 1, 1999 (1999.10.
1)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

Claims (1)

[Claims] 1. A two-wheel caster for a wheelchair having a function of turning by being attached to a front leg frame of a wheelchair, comprising: a caster shaft having a stopper protruding at a lower end portion for attaching to a front leg frame of the wheelchair; An oscillating support member having an end portion pivotally attached to a lower end portion of the caster shaft and having an abutting portion that abuts on the stopper; a rotating arm rotatably attached to the oscillating support member; and the rotating arm. A two-wheel caster for a wheelchair, comprising: a front wheel attached to a lower end of the vehicle; and an auxiliary wheel attached to a tip of the swing support member, and having a function of climbing over a step.