JP2006015025A - Manual wheelchair with continuously variable transmission mechanism - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manual wheelchair simple in structure, reduced in weight and facilitating maintenance and inspection while reducing a wheelchair operator's burden by optionally changing the rotation ratio between a wheel and a hand rim according to a road surface and a traveling situation. <P>SOLUTION: The wheel 1 and the hand rim 2 are rotatable around a same axis by power transmission through a continuously variable transmission mechanism 3, and the operator can perform variable speed operation during stop or operation. The continuously variable transmission mechanism 3 comprises an input rotating plate 10 and an output rotating plate 12 whose operating surfaces 17, 18 are formed of recessed annular curved surfaces abutting on spherical surfaces with the same center, and a transmission roller assembly having rollers 20, 21 simultaneously contacting the operating surfaces of the input rotating plate 10 and output rotating plate 12, and swinging around the center of the recessed annular curved surfaces as a fulcrum. The input rotating plate 10 is rotated integrally with the hand rim, and the output rotating plate 12 is rotated integrally with the wheel 1 to optionally change the swing angle of the transmission roller assembly, thus attaining continuously variable speed change. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a manual wheelchair having a continuously variable transmission mechanism for reducing the burden on a wheelchair operator.

Unlike conventional electric wheelchairs, conventional manual wheelchairs generally do not have a speed change mechanism, and the wheels and hand rims (control wheels) are mechanically fixed and rotate 1: 1. Wheelchair operators need to apply excessive torque to the hand rim, such as over the top step. On the other hand, when traveling on a flat road at a high speed, the wheelchair operator needs to apply a rotational motion to the hand rim in a short cycle or a long stroke, and an excessive burden is imposed. In order to solve such problems in manual wheelchairs, a large-diameter internal gear is fixed to the wheel, the hand rim is eccentrically mounted on the rotational axis of the wheel, and a gear that meshes with the internal gear of the wheel is fixed to the hand rim. However, there has been proposed one in which the rotation of the hand rim is decelerated by an internal gear mechanism and transmitted to the wheels (see Patent Document 1). In addition, as a manual wheelchair having another speed change mechanism, the wheel and the hand rim are attached to different shafts, and the wheel shaft and the hand rim shaft are decelerated through a timing belt to reduce the driving torque, thereby reducing the burden on the operator. There is also proposed one that reduces the above (see Patent Document 2). On the other hand, all of the above proposed ones rotate the wheel with a fixed reduction ratio, but a multi-stage transmission comprising a gear mechanism is provided between the hand rim shaft and the wheel shaft, and the operator operates the operating rod. By doing so, there has been proposed one that can select and operate at a constant speed drive, a deceleration drive, an acceleration drive, and a back drive via a movable cable connected to an operation rod (Patent Document 3).
Japanese Patent Laid-Open No. 09-24067 JP 2001-204769 A JP 2000-316914 A

  In the conventional manual wheelchair proposed above, the rotational drive from the hand rim to the wheel is fixed at a specific reduction ratio, or multi-speed shifting is possible, but a predetermined gear meshing ratio is alternatively selected. In both cases, only a predetermined gear ratio can be selected, and the gear ratio cannot be changed arbitrarily according to the road surface and driving conditions, so it is still necessary to reduce the burden on the wheelchair operator. Not satisfied. In addition, those having a multi-stage transmission mechanism have a problem in that the structure is complicated, which is disadvantageous for maintenance and inspection and weight reduction.

  Therefore, the present invention can arbitrarily change the rotation ratio between the wheel and the hand rim according to the road surface and the traveling situation, can hold it, can reduce the burden on the wheelchair operator, and has a structure. An object of the present invention is to provide a manual wheelchair that is simple, lightweight, and easy to maintain.

  The manual wheelchair of the present invention that solves the above-described problems is a manual wheelchair having a main body frame, a wheel rotatably provided on the main body frame, and a hand rim that manually drives the wheel to rotate. The hand rim and the wheel are transmitted through a continuously variable transmission mechanism so that an operator can perform a shifting operation while stopping or driving. It is.

By attaching the continuously variable transmission mechanism to the left and right wheels, there is no need to provide a shaft for connecting both wheels, and the wheelchair can be easily folded. The continuously variable transmission mechanism includes an input rotary plate and an output rotary plate made of a concave annular curved surface whose operating surfaces are in contact with a spherical surface having the same center, and a roller that contacts the operating surfaces of the input rotary plate and the output rotary plate. And a transmission roller assembly that oscillates around the center of the arc surface, and the input rotating plate rotates integrally with the hand rim, and the output rotating plate rotates integrally with the wheel. This makes it possible to reduce the size, simplify and reduce the weight. Further, the output rotating plate also serves as a boss portion of the wheel, and the continuously variable transmission mechanism is provided on the outer side of the main body frame, whereby the weight can be further simplified. Further, the continuously variable transmission mechanism can be provided inside the main body frame. The transmission roller assembly of the transmission mechanism can be changed by swinging it with a wire, a link mechanism, or a combination thereof, and can be easily operated by an operator. The left and right wheels are supported on separate axles, and the main body frame is configured to be foldable, thereby facilitating carrying and storage.

As described above, according to the manual wheelchair of the present invention, it is possible to arbitrarily change the rotation ratio between the wheel and the hand rim according to the road surface and the traveling situation, and to hold it, so that it is a burden on the wheelchair operator. Can be reduced. In addition, the structure is simple, the weight is reduced, and maintenance and inspection are easy. Further, according to the configuration of claim 2, the left and right can be evenly shifted, the operation is easy, and it is not necessary to provide a shaft for connecting both wheels, so that the wheelchair can be easily folded. be able to. Further, according to the configuration of the third aspect, the configuration of the continuously variable transmission mechanism is simple, can be reduced in size and weight, can be easily and reliably operated with a continuously variable transmission, and can be easily inspected. Furthermore, according to the structure of Claim 4, since the said output rotary plate serves also as the boss | hub part of a wheel, the number of parts can be reduced by that much and it can be reduced in size and weight. According to the structure of Claim 5, since the continuously variable transmission mechanism is provided inside the main body frame, it is advantageous for reducing the width of the wheelchair. According to the configuration of the sixth aspect, the speed change operation can be easily performed while the operator is stopped or during driving. And according to the structure of Claim 7, carrying and storage become easy.

Hereinafter, an embodiment of a manual wheelchair having a continuously variable transmission mechanism according to the present invention will be described in detail with reference to the drawings.
FIG. 1 is a conceptual diagram of a manual wheelchair 50 having a continuously variable transmission mechanism according to the present embodiment, where (a) is a side view thereof and (b) is a rear conceptual diagram. FIG. 2 is a cross-sectional front view of the wheel, the hand rim, and the continuously variable transmission mechanism.
In the drawing, 1 is a wheel, 2 is a hand rim, and the wheel and the hand rim are coaxially attached via a continuously variable transmission mechanism 3 described later. Boss member 5 of the hand rim 2 is rotatably bearing the fixed shaft 7, which is bearing on the bearing member 6 which is fixed to the wheelchair body frame 4, and the boss member 5 on the outer circumference of the fixed shaft 7 A sleeve member 8 that fits rotatably is integrally formed so as to protrude inward. An input rotary plate 10 constituting the continuously variable transmission mechanism 3 is keyed to the end of the sleeve member 8 so that the hand rim 2 and the input rotary plate 10 rotate integrally. The output rotating plate is rotatably supported by a bearing with respect to the fixed shaft 7. On the other hand, the boss member of the wheel 1 also serves as the output rotating plate 12 of the speed change mechanism, and is rotatably supported by the bearing 13 on the outer periphery of the sleeve member 8. Although not shown, the main body frame is configured to be foldable by any means as in a known foldable manual wheelchair.

  As shown in detail in FIGS. 3 to 6, the speed change mechanism of the present embodiment includes an input rotary plate 10 that rotates about the same axis, an output rotary plate 12, and rotation between the input rotary plate 10 and the output rotary plate 12. A transmission roller assembly 14 for transmitting force and a speed change operating means 15 for swinging the transmission roller assembly 14 are configured. The input rotary plate 10 and the output rotary plate 12 have operating surfaces 17 and 18 formed so that the operating surfaces are concave annular curved surfaces that are in contact with a spherical surface having the same center, and the operating surfaces 17 and 18 are always the same circumference. It is rotationally driven while maintaining the state located on the surface. On the other hand, the transmission roller assembly 14 rotates in frictional contact with the input-side transmission roller 20 having a contact surface that rotates in frictional contact with the operating surface 17 of the input rotating plate 10 and the operating surface 18 of the output rotating plate 12. An output side transmission roller 21 having a contact surface is integrally fixed to a transmission shaft 22, and the transmission shaft 22 is rotatably supported by a bearing member 23. The outer peripheral surfaces of the input side transmission roller 20 and the output side transmission roller 21 are circular arc surfaces having the same curvature as the operation surfaces 17 and 18, and the transmission roller assembly is centered on the spherical center O of the operation surfaces 17 and 18. By swinging, the contact position with the operating surface can be arbitrarily changed while maintaining contact with the operating surfaces 17 and 18, thereby enabling a continuously variable transmission as will be described later. .

In order to enable the transmission roller assembly 14 to swing around the spherical center O of the operating surfaces 17 and 18, the transmission roller assembly 14 includes a speed change operating means 15 having the following configuration.
That is, an operating rod 24 projecting downward is provided at the lower center of the bearing member 23, and the base end portion of the operating rod 24 is swingably provided at the lower end of the bearing member 6 fixed to the wheelchair frame. The lever member 25 is pivotally mounted via a pivot shaft 26 located at the spherical center O so as to be swingable. A flexible transmission shaft ( wire ) 27 connected to a speed change lever provided at an appropriate position of the main body frame is connected to the lower end portion of the operating rod 24. Further, as clearly shown in FIG. 3, a tension spring 30 that pulls the actuating rod 24 in a direction opposite to the pulling direction of the flexible transmission shaft 27 is suspended between the lever member 25 and the flexible transmission shaft. The transmission roller assembly 14 is biased so as to swing in the direction opposite to the pulling direction of 27. Accordingly, when the operator operates the speed change operation lever in the pulling direction, it swings in the counterclockwise direction (acceleration side) in FIG. 3, and when the operation lever is returned, the tension is applied in the clockwise direction (deceleration). To the side). Further, a tension spring 31 is provided between the lever member 25 and the bearing member 6 so that the input-side transmission roller 20 and the output-side transmission roller 21 of the transmission roller assembly 14 always have an appropriate amount on the operating surfaces 17 and 18. Forced to contact with pressure.

The manual wheelchair with a speed change mechanism according to the present embodiment is configured as described above, and when the operator rotates the hand rim, the rotational force is generated by the boss member of the hand rim 5 -the input rotating plate 10 -the input side transmission roller 20-. Transmission wheel 22-output side transmission roller 21-output rotating plate (wheel boss member) 12-wheel 1 are transmitted in this order, and the wheel is driven to rotate. 2 to 4 show a state in which the transmission roller assembly 14 of the speed change mechanism is in a neutral position. In this state, the hand rim and the wheel rotate at a ratio of 1: 1 and travel on a flat road surface at a normal speed. To do. Now, when excessive torque is required, such as when climbing uphills or oversteps on the road surface, the transmission roller assembly 14 is operated by operating the operation lever to operate the flexible transmission shaft 27 in the pulling direction. by a predetermined angle swings in the counterclockwise direction in FIG. 2. As a result, the state shown in FIG. 5 is reached, and the input side transmission roller 20 moves in the direction in which the rotation radius of the operating surface 17 of the input rotary plate 10 is small, and the rotation of the input side transmission roller is decelerated accordingly.

On the other hand, the output side transfer roller 21, the contact radius increases the working surface of the output rotary plate 12, it is possible to produce a high torque, it is possible to reduce the burden on the operator. Further, when it is desired to travel at a high speed on a place with a small load such as a flat surface, by operating the operation lever in the opposite direction, the state shown in FIG. The rotational radius of 17 is moved in the larger direction, and the rotation of the input side transmission roller is increased accordingly. On the other hand, since the output side transmission roller 21 has a small contact radius with the operating surface of the output rotary plate 12, the rotational torque can be increased and the rotational speed of the output rotary plate can be increased. On the other hand, when viewed from the side of the wheel, this state is slow and high torque with respect to the hand rim.For example, when driving downhill, the operator can easily control the rotation of the hand rim, suppress the generation of speed, and be safe. You can drive downhill.

  Thus, the speed change mechanism of the present invention can continuously change the speed according to the swing angle of the transmission roller assembly, and can be arbitrarily adjusted by the operator according to the load. Compared to a conventional manual wheelchair, it is possible to travel comfortably and safely.

  FIG. 7 shows another embodiment of the manual wheelchair according to the present invention. The manual wheelchair 51 according to this embodiment is different from the above embodiment in that a continuously variable transmission mechanism is provided inside the main body frame. . FIG. 8 is a front sectional view of the speed change mechanism, and corresponds to FIG. 3 of the above embodiment. The same members as those in the above embodiment are given the same reference numerals, and only the differences will be described.

In this embodiment, a hollow wheel shaft 41 extending from the boss member 40 of the wheel 1 to the bearing member 6 attached to the main body frame inward are bearing rotatably, output to the inner end of the hollow wheel shaft 41 The rotating plate 12 is keyed and fixed, and can rotate integrally with the wheel. On the other hand, a hand rim shaft 42 fixed to the boss member 5 of the hand rim 2 is rotatably fitted, its inner end protrudes inward from the output rotary plate 12, and the input rotary plate 10 is at its tip. It is fixed. It is the same as that of the said embodiment that each operation surface of the said input rotary plate and an output rotary plate is arrange | positioned so that the same spherical surface may contact. Similarly to the above-described embodiment, the transmission roller assembly 14 having the input-side transmission roller 20 and the output-side transmission roller 21 so as to make frictional contact with the operation surfaces 17 and 18 of the input rotation plate 10 and the output rotation plate 12 is provided. Has been placed. As described above, in the present embodiment, since the continuously variable transmission mechanism 3 is attached to the inside of the main body frame 4, the position where the hand rim and the wheel protrude to the outside of the main body frame can be made closer to the main body frame side. The overall width can be reduced.

  Since the manual wheelchair of the present invention has a continuously variable transmission mechanism and can change the rotation ratio between the wheel and the hand rim arbitrarily according to the road surface and traveling conditions, the wheelchair can be held. The burden on the operator can be reduced, and the hand rim and wheels are coaxially installed, making it possible to reduce the size and weight as with a conventional manual wheelchair without a shifting mechanism, and it is widely used as a manual wheelchair traveling indoors and outdoors. It can be done.

It is a conceptual diagram of the manual wheelchair which concerns on embodiment of this invention, (a) is a side view, (b) is a rear view. It is front sectional drawing which shows a wheel and a hand rim, and a continuously variable transmission mechanism part. It is a principal part cross-sectional enlarged view of FIG. FIG. FIG. 5 is a rear view corresponding to FIG. 4 in a state where the continuously variable transmission mechanism is in a deceleration state. FIG. 5 is a rear view corresponding to FIG. 4 in a state where the continuously variable transmission mechanism is in an accelerated state. It is a back surface conceptual diagram of the manual wheelchair which concerns on other embodiment of this invention. It is a principal part expanded front sectional view which shows a wheel, a hand rim, and a continuously variable transmission mechanism part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Wheel 2 Hand rim 3 Continuously variable transmission mechanism 4 Main body frame 5, 11, 40 Boss member 6 Bearing member 7 Fixed shaft 8 Sleeve member 10 Input rotary plate 12 Output rotary plate 13 Bearing 14 Transmission roller assembly 15 Shifting operation means 17, 18 Actuation surface 20 Input side transmission roller 21 Output side transmission roller 22 Transmission shaft 23 Bearing member 24 Actuation rod 25 Lever member 26 Pivot shaft 27 Flexible transmission shaft (wire)
30 and 31 tension spring 41 hollow wheel shaft 42 hand rim axis 50 and 51 manual wheelchair

Claims (7)

In a manual wheelchair having a main body frame, a wheel rotatably provided on the main body frame, and a hand rim for manually rotating the wheel, the wheel and the hand rim are rotatable about the same axis, A manual wheelchair characterized in that the wheel is transmitted through a continuously variable transmission mechanism so that an operator can perform a shifting operation while stopping or driving. The manual wheelchair according to claim 1, wherein the continuously variable transmission mechanism is attached to left and right wheels. The continuously variable transmission mechanism has an input rotary plate and an output rotary plate made of a concave annular curved surface whose operating surfaces are in contact with a spherical surface having the same center, and a roller that contacts the operating surfaces of the input rotary plate and the output rotary plate. 2. A transmission roller assembly that swings about the center of the spherical surface, wherein the input rotary plate rotates integrally with a hand rim, and the output rotary plate rotates integrally with a wheel. Or the manual wheelchair as described in 2. The manual wheelchair according to any one of claims 1 to 3, wherein the output rotating plate also serves as a boss portion of a wheel, and the continuously variable transmission mechanism is provided outside a main body frame. The manual wheelchair according to claim 1, wherein the continuously variable transmission mechanism is provided inside the main body frame. The manual wheelchair according to any one of claims 1 to 5, wherein the transmission roller assembly of the speed change mechanism can be speed-changed by swinging with a wire, a link mechanism, or a combination thereof. The manual wheelchair according to any one of claims 1 to 5, wherein the left and right wheels are supported by separate axles, and the main body frame is foldable.

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