JP2014124317A - Wheelchair Drive device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain the simplification of a structure and the reduction of a cost without requiring the use of a roller, etc. incorporating a one-way clutch in pushing to turn wheels in a circumferential direction with a handle operation.SOLUTION: A wheelchair drive device 3 includes: right and left handles 4 vertically arranged on both sides of a wheelchair body 1 in order to enable a reciprocative operation in a front and rear direction; and a pair of right and left drive plates 6 that are arranged between the wheelchair body 1 and wheels 2 and whose proximal end parts are turnably supported at positions closer to front sides than the centers of rotation of the wheels 2. The center part in the length of each handle 4 is turnably supported by the front end part of each drive plate 6. Each pressure member 5 is attached to the lower end part of each handle 4 so as to face the outer peripheral surface of a tire part 20 of the wheel 2. A return spring 7 for energizing the drive plate 6 in a direction to pull back the handle 4 is arranged between each drive plate 6 and the wheelchair body 1.

Description

  The present invention relates to a wheelchair drive device for driving a wheelchair by applying human power to left and right wheels, and in particular, the present invention relates to a wheelchair drive device for rotating and driving wheels by a handle operation.

  As shown in FIG. 9, a conventional typical wheelchair has left and right wheels 2, 2 supported on both sides of a vehicle body 1 having a seat portion 10 so as to freely rotate, and has a wheel-like shape outside each wheel 2. The hand rim 9 is provided integrally with the left and right wheels 2, respectively. In the figure, reference numeral 11 denotes left and right frames constituting the vehicle body 1. The left and right wheels 2 are attached to each frame 11, and casters 12 and footrests 13 are attached to lower positions of the frames 11. ing.

  A user sitting on the seat 10 puts his hand on the outer peripheral surface of each of the left and right hand rims 9 and pushes the hand rim 9 forward along the circumferential direction, thereby rotating the left and right wheels 2 to run the wheelchair. However, in this type of wheelchair, hands are placed on the left and right hand rims 9 to rotate them, so that the hands are dirty and unsanitary, and each hand rim 9 is rotated or braked. However, there is a problem that a large force is required to make the hand tired and stable running and stopping are not easy.

  Instead of the conventional method of manually operating the left and right hand rims, the left and right handles are vertically installed on both sides of the vehicle body so that they can be moved back and forth, and the rollers pressed against the tire parts of the left and right wheels are operated by the handle There has been proposed a system in which a wheel is rotationally driven by responding to (see, for example, Patent Document 1).

JP-A-10-225485

  However, the wheelchair drive device described above restricts the rotation of the roller when pushing the handle forward so that the roller pushes the tire portion of the wheel in the circumferential direction, while the roller moves backward when the handle is pulled back. Therefore, the roller must have a built-in one-way clutch that rotates only on one side, resulting in a complicated structure and high cost. There is a problem.

The present invention has been made paying attention to the above-mentioned problem, and it is not necessary to use a roller with a built-in one-way clutch to rotate the wheel by pushing the handle in the circumferential direction. An object of the present invention is to provide a wheelchair drive device that realizes cost reduction.
Another object of the present invention is to provide a safe wheelchair drive device that can run without a caregiver even on an uphill and does not have the possibility of the wheelchair moving backward due to its own weight in the middle of the hill. There is to do.

  The wheelchair drive device according to the present invention includes left and right wheels that are rotatably attached to both sides of the vehicle body, left and right handles that are vertically installed on both sides of the vehicle body so as to be able to reciprocate back and forth, and responsive to the handle operation. And a pressing member that presses and rotates the wheel in the circumferential direction while being pressed against the tire portion on the outer periphery of the wheel, and is between the vehicle body and the wheel and is the center of rotation of the wheel or the rotation of the wheel. It has a pair of left and right drive plates whose rear end portions are rotatably supported at positions closer to the front side than the center. The center of the length of the handle is rotatably supported at the front end of each drive plate, and the pressing member is attached to the lower end of each handle so as to face the outer peripheral surface of the tire portion of the wheel. A return spring is provided between each drive plate and the vehicle body to urge the drive plate in a direction to pull back the handle.

In the wheelchair drive device configured as described above, when the handle is pushed forward, first, the handle is tilted forward with respect to the drive plate at the front end portion of the drive plate, whereby the pressing member is pressed against the tire portion of the wheel. When the handle is further pushed forward, the drive plate rotates forward together with the handle, and the pressing member pushes the tire portion in the circumferential direction while being pressed against the tire portion. Will move forward.
Next, when the handle is pulled back, first, the handle is tilted rearward with respect to the drive plate at the front end portion of the drive plate, so that the pressing of the pressing member to the tire portion of the wheel is released. When the handle is further pulled back, the drive plate receives the pulling force of the return spring and rotates backward together with the handle, and the pressing member returns in a state where the pressure on the tire portion is released. By repeating the same steering operation, the rotational driving force continues to act on the wheel, and the wheelchair continues to move forward.

  In a preferred embodiment of the present invention, the pressing member is composed of a pair of parallel shafts parallel to each other, and is attached to the distal end portion of a support plate whose base end portion is rotatably supported by the lower end portion of the handle. It is attached so that the outer peripheral surface of each round shaft body faces the outer peripheral surface of the tire portion of the wheel.

  According to this embodiment, when the steering wheel is pushed forward, the pair of round shaft bodies are pressed against the tire portion in a stable state, and the tire portion is pushed in the circumferential direction in the pressed state. Driving force acts.

  In another wheelchair drive device according to the present invention, a reverse movement prevention mechanism for preventing the reverse movement of the wheelchair by preventing the reverse rotation of the wheel at a position above each wheel is further provided. Each reverse prevention mechanism has a leg plate portion whose upper end portion is supported to freely rotate on a vertical line passing through the center of rotation of the wheel, and the lower end of the leg plate portion is on the tire portion on the outer periphery of the wheel. The length is set so as to abut at the position.

  In the wheelchair drive device configured as described above, when the wheel rotates forward, the lower end of the leg plate portion slides on the tire portion on the outer periphery of the wheel while the leg plate portion of the receding prevention mechanism hangs down under its own weight. There is no hindrance to the rotation of the wheel, and no braking force acts on the wheel. On the other hand, if the wheel tries to reverse in the direction in which the wheelchair moves backward on an uphill, the lower end of the leg plate part is pressed so as to bite into the tire part of the wheel, so that braking force acts on the wheel and the wheel reverses. Is prevented and the wheelchair does not retreat.

  In a preferred embodiment of the present invention, the backward movement prevention mechanism includes a release mechanism that releases the function of holding the lower end of the leg plate portion in a state where it does not contact the tire portion of the wheel and preventing the reverse rotation of the wheel.

  According to this embodiment, since the wheelchair can be moved backward by releasing the function of preventing the reverse rotation of the wheel by the release mechanism, the wheelchair is moved backward even when entering a narrow road where a U-turn is difficult. You can easily escape from the narrow road.

  According to the present invention, since the wheel is rotationally driven by operating the handle, there is no fear of dirtying the hand as in the method of manually operating the left and right hand rims, and it is possible to perform stable and comfortable driving. In addition, since the wheel is rotated in the circumferential direction by operating the handle to rotate the wheel, a roller with a built-in one-way clutch or the like is not used, so that the structure can be simplified and the cost can be reduced. In addition, a reverse-prevention mechanism that prevents the wheelchair from reversing by preventing the wheel from reversing, prevents the wheelchair from retreating under its own weight even on an uphill, allowing it to travel uphill without a caregiver. It is.

It is a side view which shows the external appearance of the wheelchair by which the wheelchair drive device of this invention was mounted. It is a side view which expands and shows the principal part of a wheelchair drive device. It is sectional drawing which follows the AA line of FIG. It is a figure for demonstrating the principle of a wheelchair drive device. It is a side view which shows the state which a handle tilts ahead with respect to a drive plate when pushing a handle forward. It is a side view which shows the state which a handle tilts back with respect to a drive plate, when pulling back a handle. It is a side view which shows operation | movement of a press member when pushing a handle forward. It is a side view which shows operation | movement of a press member when pulling back a handle back. It is a perspective view which shows the external appearance of the conventional wheelchair.

  FIG. 1 shows the appearance of a wheelchair equipped with the wheelchair drive device of the present invention, and left and right wheels 2 and 2 are attached to both sides of a vehicle body 1 so as to freely rotate. Each wheel 2 has a rubber tire portion 20 provided around an outer periphery of a metal wheel 21. In the figure, 22 is a hub of the wheel 21 and 23 is a spoke.

  The vehicle body 1 has left and right frames 11, 11 and side plates 16 fixed between the upper and lower frames 11, 11, and a seat (not shown) between the left frame 11 and the right frame 11. Components such as a footrest and the like are attached. A caster 12 is attached to the lower part of the front end part of each of the left and right frames 11, and a grip 14 for pushing is attached to the upper part of the rear end part. The caster 12 is rotatably supported by the yoke 15 so that the ground contact position is aligned with the ground contact position of the left and right wheels 2 on the same horizontal plane.

  The wheelchair drive device 3 mounted on the wheelchair is configured to prevent the reverse rotation of the left and right wheels 2 and 2 and the pair of left and right wheels 2 and 2 that rotate the left and right wheels 2 and 2 forward to advance the wheelchair. It includes a pair of left and right retreat prevention mechanisms 31 that prevent the wheelchair from retreating on a slope. The left and right traveling drive mechanisms 30 are respectively provided on both sides of the vehicle body 1 and inside the wheels 2. The left and right retreat prevention mechanisms 31 are respectively attached to the upper positions of the wheels 2.

  As shown in FIGS. 2 and 3, each of the left and right traveling drive mechanisms 30 includes a handle 4, a pressing member 5, a drive plate 6, and a return spring 7 as components. The handle 4 is provided with a cylindrical gripping portion 40 at the upper end, and is vertically provided so as to be able to perform reciprocating operations in the front and rear directions (directions indicated by arrows f and b in FIGS. 1 and 2). Yes. In the standby state (the state indicated by the solid line in FIG. 1), the handle 4 is in a posture slightly inclined rearward. By pushing the handle 4 so as to push it forward f, the handle 4 is indicated by a one-dot chain line in the figure. Then, after a standing posture, it shifts to a slightly inclined posture. The handle 4 is supported at the center of the length by the drive plate 6 by a pivot 41 so that the handle 4 can freely rotate. The pressing member 5 faces the outer peripheral surface of the tire portion 20 of the wheel 2 at the lower end of the handle 4. It is attached.

  The pressing member 5 is for pressing and rotating the wheel 2 in the circumferential direction while being pressed against the tire portion 20 on the outer periphery of the wheel 2. When the handle 4 is pushed forward f to tilt the handle 4 forward with respect to the drive plate 6, the lower end portion of the handle 4 displaces the pressing member 5 toward the tire portion 20 with the pivot 41 as a fulcrum. . When the handle 4 is pulled back to the rear b and the handle 4 is tilted rearward with respect to the drive plate 6, the lower end of the handle 4 moves away from the tire portion 20 with the pivot 41 as a fulcrum. Displace.

  The pressing member 5 in the illustrated example is composed of a pair of roller-shaped round shafts 50 and 50 that are parallel to each other, and a base end portion of a support plate 51 that forms a substantially equilateral triangle at the lower end portion of the handle 4 is a pin 52. The round shaft bodies 50 and 50 are attached to the support plate 51 integrally with the support plate 51 so that the outer peripheral surfaces thereof face the outer peripheral surface of the tire portion 20 of the wheel 2. It has been. Note that the pressing member 5 is not limited to the one in this embodiment, and can be constituted by a single round shaft.

  The drive plate 6 is supported between the vehicle body 1 and the wheel 2 at a position closer to the front side than the center of rotation of the hub 22 of the wheel 2, and a rear end portion thereof is rotatably supported by the side plate 16 by a pivot 63. . The drive plate 6 has a length such that the front end reaches the outer peripheral portion of the wheel, and the vertical plate 62 is integrally formed on the front end of the horizontal plate 61 upward. A base end portion of the horizontal flat plate portion 61 is rotatably supported by the pivot shaft 63, and a central portion of the length of the handle 4 is rotatably supported by the pivot shaft 41 at an upper end portion of the vertical plate portion 62.

  A first stopper 42 is provided on the vertical plate portion 62 of the drive plate 6. When the handle 4 is pulled back to the rear b, the handle 4 tilts backward with respect to the drive plate 6 with the pivot 41 as a fulcrum, and the lower end portion of the handle 4 hits the first stopper 42. As a result, further tilting of the handle 4 with respect to the drive plate 6 is restricted, and the handle 4 rotates integrally with the drive plate 6 for further pull-back operation of the handle 4. When the handle 4 is pushed forward f, the handle 4 tilts forward with the pivot 41 as a fulcrum with respect to the drive plate 6, and the lower end of the handle 4 pulls the pressing member 5 to displace it. Since 5 is pressed against the tire portion 20 of the wheel 2, further tilting of the handle 4 with respect to the drive plate 6 is restricted.

  A second stopper 17 for restricting the rotation angle of the drive plate 6 that rotates together with the handle 4 protrudes from the lower position of the side plate 16. When the drive plate 6 is rotated integrally by pushing the handle 4 forward f, the horizontal plate portion 61 of the drive plate 6 abuts against the second stopper 17, thereby rotating the handle 4 forward f. Be regulated. On the other hand, when the handle 4 is pulled back b and the drive plate 6 is integrally rotated in the direction opposite to the above, the round shaft bodies 50 and 50 of the pressing member 5 are in the tire portion 20 at a predetermined angular position described later. , The rotation of the rear b of the drive plate 6 is restricted.

  FIG. 4 is an explanatory diagram of the principle of the travel drive mechanism 30 described above, in which P1 is an angular position of the drive plate 6 when the handle 4 is in a standby state (hereinafter referred to as “first angular position”). ), P2 is the angular position of the driving plate 6 when the driving plate 6 hits the second stopper 17 (hereinafter referred to as “second angular position”), and θ is the first angular position P1 and the second angular position. This is an angle between the angle position P2, that is, an angle range in which the drive plate 6 rotates by reciprocating the handle 4 back and forth.

In the figure, reference numeral 5 denotes a pressing member represented by a single round shaft, and when the handle 4 is pushed forward f from the standby position shown in FIG. 1, the drive plate 6 is moved to the first angular position P1. Yes, after the pressing member 5 is pressed against the tire portion 20 of the wheel 2 to be in a pressed state (indicated by a dotted line in the figure), the drive plate 6 is rotated by the angle θ in the pressed state, At the second angular position P2, it hits the second stopper 17 and stops.
Subsequently, when the handle 4 is pulled back to the rear b, the pressing member 5 is separated from the tire portion 20 of the wheel 2 and the pressing state is released (indicated by a dotted line in the figure), and then the pressing state is released. The drive plate 6 rotates in the opposite direction by the angle θ. When the pressing member 5 is pressed against the tire portion 20 of the wheel 2 and the rotation is restricted, the drive plate 6 has returned to the first angular position P1.

  In the above embodiment, the rotation center of the drive plate 6 is set forward with respect to the rotation center of the wheel 2. However, the present invention is not limited to this, and the rotation center of the drive plate 6 is the rotation of the wheel 2. It is also possible to match the center, and in this case, a stopper is also provided at the standby position of the drive plate 6 so that the pull back operation of the handle 4 is restricted by the stopper.

  Returning to FIGS. 1 and 2, a return spring for urging the drive plate 6 in a direction (rearward b) for pulling back the handle 4 between the vertical plate portion 62 of the drive plate 6 and the longitudinal frame 11. 7 is stretched. As the return spring 7, it is desirable to use a coil spring that generates a spring force by shifting from a compressed state to an extended state.

  The retraction prevention mechanism 31 includes a leg plate portion 32 and a locking portion 37 disposed above the wheel 2, and the locking portion 37 of this embodiment is configured using a permanent magnet. The leg plate portion 32 has a structure in which a cylindrical shaft support portion 34 having a cylindrical shape at the upper end is rotatably supported by a pin 33 on a frame 11 positioned on a vertical line passing through the rotation center of the wheel 2. The length of the leg plate part 32 is set so that the lower end of the leg part comes into contact with the tire part 20 on the outer periphery of the wheel 2 at a position in front of the vertical line.

  A lever 35 for manual operation and an arm 36 that is locked to the locking portion 37 by magnetic attraction are integrally formed on the outer peripheral surface of the shaft support portion 34. The engaging portion 37 and the arm 36 constitute a release mechanism for releasing the function of preventing the reverse rotation of the wheel 2, and the lever 35 is operated to move the leg plate portion 32 in the direction indicated by the arrow d in the figure. When the arm 36 is rotated, the arm 36 abuts against a locking portion 37 attached to the frame 11 and is magnetically attracted. Accordingly, the lower end portion of the leg plate portion 32 is separated from the tire portion 20 of the wheel 2 and is held in a state where it is not in contact with the tire portion 20. In this embodiment, the leg plate portion 32 is formed of a magnetic material such as iron, and the arm 36 integral with the leg plate portion 32 is magnetically attracted to the locking portion 37. However, the arm 36 is a non-magnetic material. In this case, a magnetic body such as an iron plate is attached to the tip of the arm 36. In this embodiment, the arm 36 is locked to the locking portion 37 by a magnetic method. However, the present invention is not limited to this, and a hook or the like is provided at the tip of the arm 36 to mechanically connect the locking portion 37. It may be configured to be caught.

  In FIG. 2, L1 is the distance between the grip portion 40 of the handle 4 and the pivot 63 of the drive plate 6, L2 is the distance between the pivot 63 and the pressing member 5, and the ratio of the distance L1 to the distance L2 is set as large as possible. If this is done, the force applied to the grip portion 40 is sufficiently amplified and transmitted to the round shaft bodies 50, 50 of the pressing member 5, so that the wheelchair can be advanced with a small force, especially on an uphill wheelchair. It becomes easy to run.

  In the wheelchair drive device 3 having the above-described configuration, as shown in FIG. 5, when the handle 4 is pushed so as to be pushed forward f from the standby position, the handle 4 is first moved to the drive plate 6 in the vertical plate portion 62 of the drive plate 6. 6 is tilted forward by a predetermined angle (indicated by a one-dot chain line in FIG. 5). Thereby, as shown in FIG. 7 (A), the round shaft bodies 50, 50 of the pressing member 5 are pressed against the tire portion 20 of the wheel 2 to be in a pressed state (in FIG. State shown.) When the handle 4 is further pushed forward f, the drive plate 6 is rotated integrally with the handle 4, and the round shaft bodies 50, 50 of the pressing member 5 are pressed against the tire portion 20 in the pressed state. Is pushed in the circumferential direction, the wheel 2 rotates and the wheelchair moves forward (shown in FIGS. 7B and 7C).

  After the driving plate 6 reaches the second angular position P2 described above, when the force pushing the handle 4 forward f is released, the handle 4 receives the spring force of the return spring 7 and moves backward b with respect to the driving plate 6. Tilt by a predetermined angle (indicated by a one-dot chain line in FIG. 6). As a result, the pressing force applied to the tire portion 20 of the wheel 2 by the round shaft bodies 50, 50 of the pressing member 5 is released (indicated by a one-dot chain line in FIG. 7C). No braking force acts on the wheel 2, and the wheel 2 continues to rotate freely.

It is possible to adjust the pressing force applied to the tire portion 20 of the wheel 2 by the round shaft body 50 of the pressing member 5 by adjusting the force pushing the handle 4 forward. By applying a small braking force, the wheelchair can travel safely.
Further, when the driving plate 6 is at the second angular position P2, if the pressing force to the handle 4 is further increased, the round shaft bodies 50, 50 of the pressing member 5 are pressed more strongly against the tire portion 20 of the wheel 2, Rapid braking can be applied to the wheel 2 (indicated by a two-dot chain line in FIG. 7C).

As soon as the drive plate 6 reaches the second angular position P2, the handle 4 is pulled back to the rear b. In the vertical plate portion 62 of the drive plate 6, the handle 4 is first moved to the rear b with respect to the drive plate 6. Tilt by an angle (indicated by a dashed line in FIG. 6). Thereby, the pressing force to the tire part 20 of the wheel 2 by the round shaft bodies 50, 50 of the pressing member 5 is released (indicated by a one-dot chain line in FIG. 8A). When the handle 4 is further pulled back b, the drive plate 6 receives the pulling force of the return spring 7 and rotates in the direction opposite to the above integrally with the handle 4, so that the round shaft bodies 50, 50 of the pressing member 5 are tires. Returning to the standby position is performed in a state where the pressing to the portion 20 is released (shown in FIGS. 8B and 8C).
By repeating the same steering operation, the rotational driving force continues to act on the wheel 2 and the wheelchair continues to move forward.

  When the wheel 2 rotates forward, the lower end of the leg plate portion 32 of the retreat prevention mechanism 31 slides on the tire portion 20 of the wheel 2 while hanging down due to its own weight, so that the leg plate portion 32 hinders the rotation of the wheel 2. No braking force is applied to the wheel 2. On the other hand, when the wheel 2 tries to reverse in the direction in which the wheelchair moves backward on the uphill, the lower end of the leg plate portion 32 of the reverse prevention mechanism 31 is pressed so as to bite into the tire portion 20 of the wheel 2. A braking force acts on the wheelchair to prevent the wheels from reversing and the wheelchair does not move backward.

DESCRIPTION OF SYMBOLS 1 Car body 2 Wheel 3 Wheelchair drive device 4 Handle 5 Press member 6 Drive plate 7 Return spring 20 Tire portion 31 Retraction prevention mechanism 32 Leg plate portion 50 Round shaft body 51 Support plate

Claims (4)

  Left and right wheels mounted on both sides of the car body freely, left and right handles vertically installed on both sides of the car body so as to be able to reciprocate back and forth, and tires on the outer periphery of the wheel in response to the handle operation In a wheelchair drive device provided with a pressing member that presses and rotates the wheel in the circumferential direction in a pressed state, between the vehicle body and the wheel and at a position closer to the front side than the rotation center of the wheel or the rotation center of the wheel It has a pair of left and right drive plates whose rear ends are freely supported, and the center of the length of the handle is supported freely at the front end of each drive plate, and at the lower end of each handle The pressing member is attached to face the outer peripheral surface of the tire portion of the wheel, and a return spring is provided between each drive plate and the vehicle body to urge the drive plate in a direction to pull back the handle. Wheelchair drive device.   The pressing member is composed of a pair of round shaft bodies parallel to each other, and the outer peripheral surface of each round shaft body is a wheel at the distal end portion of a support plate whose base end portion is rotatably supported at the lower end portion of the handle. The wheelchair drive device described in Claim 1 attached so that the outer peripheral surface of the tire part of this may be opposed.   3. The wheelchair drive device according to claim 1, further comprising a reverse prevention mechanism for preventing the wheelchair from reversing by preventing a reverse rotation of the wheel at a position above each wheel. The prevention mechanism has a leg plate portion whose upper end portion is rotatably supported on a vertical line passing through the center of rotation of the wheel, and the lower end of the leg plate portion is positioned at a front side of the vertical line on the tire portion on the outer periphery of the wheel. A wheelchair drive device having a length set to abut.   The wheelchair drive device according to claim 3, wherein the reverse prevention mechanism includes a release mechanism that releases a function of holding the lower end of the leg plate portion in a state where the lower end of the leg plate portion is not in contact with the tire portion of the wheel to prevent the reverse rotation of the wheel. .

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