Electric wheelchair

Abstract

To provide an electric wheelchair that can easily escape from derailment even when the derailment occurs, without a significant change in a structure.SOLUTION: An electric wheelchair 10 has, for example: a rear plate 30 rigid-connected to a rear wheel 12R; a hand-push part 32 extending upward from the rear plate 30; and an auxiliary wheel 33 pivotally supported by the rear plate 30 and capable of turnabout. When the hand-push part 32 is operated, the rear plate 30 is inclined with the auxiliary wheel 33 as a fulcrum, so that the rear wheel 12R is lifted.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to an electric wheelchair.

Background Art

[0002] Conventionally, as a means of transportation that can be easily used by the elderly, people with walking difficulties due to injuries, etc., electric wheelchairs (sometimes referred to as senior cars, electric carts, etc.) have become widespread. Since electric wheelchairs are heavy, if wheel detachment occurs, it is necessary to lift them with multiple people to escape. Therefore, when the driver requests assistance, it takes time to wait for assistance until escaping.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Conventionally, when wheel detachment occurs, it has been disclosed that the auxiliary wheels are lowered by a hydraulic unit and driven to escape. In the case of such an electric wheelchair, it is necessary to provide a mechanism for lowering the auxiliary wheels, a hydraulic unit, and an inclination sensor for detecting inclination. Therefore, it is necessary to significantly change the structure of the electric wheelchair.

[0005] An object of the present invention is to provide an electric wheelchair that can easily escape from wheel detachment even when wheel detachment occurs without significantly changing the structure.

Means for Solving the Problems

[0006] To achieve the above object, a wheelchair according to an embodiment of the present invention has, for example, a rear plate rigidly connected to a rear wheel, a push handle extending upward from the rear plate, and an auxiliary wheel pivotally supported by the rear plate and capable of changing direction. When the push handle is operated, the auxiliary wheel serves as a fulcrum, and the rear plate is tilted to lift the rear wheel.

[0007] According to this configuration, when the push handle is operated, the auxiliary wheel serves as a fulcrum, and the rear wheel can be lifted. Thus, for example, when a wheel detachment occurs, the wheelchair can be escaped from the wheel detachment by rotating the auxiliary wheel in the moving direction of the wheelchair at the height where the rear wheel is lifted.

[0008] Further, the wheelchair according to an embodiment of the present invention may have, for example, at least a depressible footrest provided on the rear plate.

[0009] According to this configuration, for example, when a wheel detachment occurs, by operating the push handle and the footrest, the force for lifting the rear wheel can be distributed between the push handle and the footrest. Thus, the rear wheel can be lifted by the distributed force.

[0010] Further, the wheelchair according to an embodiment of the present invention may have, for example, a wire connecting the rear plate and a steering shaft. When the wire is pulled backward, the steering shaft may be rotated to direct the front wheel in the straight-ahead direction.

[0011] According to this configuration, for example, when the rear plate is tilted and the wire is pulled, the steering shaft can be rotated so that the front wheel faces the straight-ahead direction. Thus, when the wire is pulled, the front wheel can be held in the straight-ahead direction, and the swinging of the front wheel when escaping from the detachment point can be suppressed.

[0012] In addition, in the electric wheelchair according to the embodiment of the present invention, for example, the rear plate may be connected to the rear wheels via at least the vehicle body frame, the motor, or the drive shaft.

[0013] According to this configuration, for example, it is possible to easily attach the rear plate to the electric wheelchair.

Advantages of the Invention

[0014] According to the present invention, it is possible to provide an electric wheelchair that can easily escape from wheel lift even when the rear plate is attached without making significant structural changes.

Brief Description of the Drawings

[0015]

Figure 1

Figure 2

Figure 3

Modes for Carrying Out the Invention

[0016] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0017] FIG. 1 is an exemplary and schematic side view showing the configuration of an electric wheelchair according to an embodiment.

[0018] The electric wheelchair 10 is, for example, a four-wheeled vehicle in which the front wheels 12F are steering wheels and the rear wheels 12R are drive wheels. The rear wheels 12R are rotationally driven, for example, by a motor 14 with an electromagnetic brake 14a. The motors 14 are arranged for each of the left and right rear wheels 12R, and the rotation direction and rotation speed are controlled by the control unit 16 to achieve speed control, forward travel, and reverse travel.

[0019] The electromagnetic brake 14a is, for example, of the non-excitation operation type, and when the power supply is cut off, it fixes the motor shaft or the like to lock the rear wheel 12R, preventing the electric wheelchair 10 from inadvertently moving (traveling) when the power is cut off. The electromagnetic brake 14a is an example of a locking mechanism.

[0020] Note that the drive method of the rear wheel 12R can be appropriately selected. As shown in FIG. 1, it may be a type in which the motor 14 is directly connected to the rear wheel 12R, or a type in which the motor 14 and a transmission mechanism are combined to rotate the drive shaft to drive the left and right rear wheels 12R. Also, the rear wheel 12R may be of the in-wheel motor type incorporating the motor 14.

[0021] A seat 20 is disposed on the upper surface of the housing 18 that pivotally supports the rear wheel 12R. A driver sitting on the seat 20 can operate the electric wheelchair 10 by placing their feet on the step 22 provided in front of the housing 18 and gripping the handle 24, and steering the handle 24.

[0022] The handle 24 is connected to a steering shaft 50 covered by a front cover 26. The handle 24 steers the front wheel 12F via a link 52 connected below the steering shaft 50 to determine the traveling direction of the electric wheelchair 10.

[0023] One handle grip 24a of the handle 24 is provided with, for example, a throttle 24b, and by rotating the throttle 24b, it is possible to adjust the traveling speed of the electric wheelchair 10. Note that by returning the throttle 24b from the rotated position, it is possible to decelerate by the regeneration of the motor 14.

[0024] Also, in another embodiment, a brake lever (not shown) may be provided in front of the handle grip 24a. In addition, an accelerator pedal or a brake pedal may be provided on a part of the step 22, and the speed of the electric wheelchair 10 may be adjusted according to the amount of depression of the accelerator pedal or the brake pedal.

[0025] Between the left and right handle grips 24a that constitute the handle 24, a meter panel 28 is provided, on which a speed indicator, a remaining amount indicator (charge amount indicator) of the battery 17 described later, various displays lamps (direction indicator operation lamp, warning lamp), etc. are arranged.

[0026] The battery 17 is housed in the front cover 26, for example. The motor 14 of the electric wheelchair 10 is rotationally driven by receiving power supply from the battery 17. Then, it can travel by rotating the rear wheels 12R. The battery 17 is, for example, a lithium-ion battery.

[0027] Next, the rear plate 30 is, for example, a rectangular plate material as an example. The rear plate 30 has a push portion 32 extending upward from the upper surface of the rear plate 30, a footrest portion 31 located behind the push portion 32 provided on the rear plate 30, and a pair of left and right auxiliary wheels 33 pivotally supported at the rear of the rear plate 30.

[0028] The rear plate 30 is rigidly connected to the rear wheels 12R. Specifically, for example, the front portion of the rear plate 30 may be connected to the rear wheels 12R via at least the vehicle body frame, the motor 14, or the drive shaft.

[0029] Being rigidly connected means that the rear wheels 12R and the rear plate 30 are connected via another member. For example, when the front portion of the rear plate 30 moves upward, the rear wheels 12R also move upward in conjunction. Specifically, for example, when the front portion of the rear plate 30 is inclined upward, the rear wheels 12R are also lifted in conjunction with the rear plate 30 via another member.

[0030] The hand-pushing part 32 includes a pair of left and right bars extending upward from the upper surface or side surface of the rear plate 30, and a gripping part where the upper ends of the pair of left and right bars are connected. The gripping part can be operated by, for example, a driver or a caregiver to move the electric wheelchair 10. The hand-pushing part 32 is operated when moving the wheelchair by hand or when performing wheel removal and escape. The hand-pushing part 32 is, for example, a hand-pushing handle or a hand-pushing lever as an example.

[0031] The footrest part 31 is pivotally supported at the rear part of the rear plate 30, for example, and may be rotatable about the rear plate 30 as an axis. In the case of a rotatable type, for example, when stored, it may be stored at a position in front of the rear end of the rear plate 30. When in use, it is rotated from the storage position and fixed at the footrest position to enable footrest. Thereby, when stored, space for the caregiver can be secured. The footrest part 31 is, for example, a footrest pedal as an example. In addition, the footrest part 31 may be a slide type, a folding type, or the like.

[0032] The auxiliary wheels 33 are a pair of left and right wheels provided at the rear part of the rear plate 30. The auxiliary wheels 33 are pivotally supported on the side part of the rear plate 30. The auxiliary wheels 33 enable the electric wheelchair 10 to change direction at the position where they contact the ground. Since they are wheels that can change direction, it is easy to move the electric wheelchair 10 during wheel removal and escape. For example, an all-directional wheel that can turn in each direction of forward and backward, left and right, and diagonally may be used as an example. Or a caster may be used as an example.

[0033] The auxiliary wheels 33 serve as a fulcrum for tilting the rear plate 30 when the hand-pushing part 32 is operated (pulled backward and downward). The auxiliary wheels 33 may be, for example, at a height away from the ground before the hand-pushing part 32 is operated and in contact with the ground when operated.

[0034] The auxiliary wheels 33 serve as a fulcrum for tilting the rear plate 30 when the footrest part 31 is pressed down. The auxiliary wheels 33 may be, for example, at a height away from the ground before the footrest part 31 is pressed down and in contact with the ground when the footrest part 31 is pressed down.

[0035] Also, in other embodiments, the footrest 31 may be any member that can operate (push down) the rear plate 30 downward. For example, the footrest 31 may be disposed at a height that can be operated by the knees and hips and may be operated by parts other than the feet.

[0036] FIG. 2 is an exemplary and schematic side view showing the configuration when the wheels of the electric wheelchair 10 according to the embodiment are lifted.

[0037] When the wheelchair gets derailed, for example, the operation of lifting the rear wheel 12R to escape from the derailment will be described.

[0038] When derailment occurs, the driver or caregiver operates the handrail 32 downward (in the direction of arrow A1), so that the auxiliary wheel 33 in contact with the ground serves as a fulcrum and the front part of the rear plate 30 tilts upward. As a result, the rear wheel 12R rigidly connected to the rear plate 30 is lifted upward.

[0039] Next, when the rear wheel 12R is lifted to a height above a predetermined level, by operating the handrail 32 in the direction in which the rear wheel 12R escapes from the derailed position, the auxiliary wheel 33 rotates and moves, thereby enabling escape.

[0040] For example, when at least the rear wheel 12R gets derailed, the driver or caregiver first performs an operation of pulling the handrail 32 downward to lift the rear wheel 12R. As a result, the auxiliary wheel 33 comes into contact with the ground and serves as a fulcrum, and the front part of the rear plate 30 can be tilted upward.

[0041] Therefore, the rear plate 30 can lift the rear wheel 12R connected via at least the vehicle body frame, the motor 14, or the drive shaft.

[0042] Next, when the rear wheel 12R is lifted to a height above a predetermined level, by operating the handrail 32 to move the rear wheel 12R from the derailed position, it is possible to escape from the derailment.

[0043] Furthermore, in order to reduce the force when lifting the rear wheel 12R, in accordance with the operation of pulling the hand-pushing portion 32, for example, the footrest portion 31 is operated (pressed down) downward (in the direction of arrow A2). Thereby, compared with the case of operating only with the hand-pushing portion 32, the force can also be dispersed to the footrest portion 31, and the force for operating (pulling) the hand-pushing portion 32 can be reduced to lift the rear wheel 12R.

[0044] Also, in another embodiment, the hand-pushing portion 32 may be a pair of left and right bars extending upward from the rear plate 30 and being telescopically extendable in the height direction (vertical direction). For example, when operating (pulling) the hand-pushing portion 32 backward and downward to lift the front wheel 12F or the rear wheel 12R, the length of the hand-pushing portion 32 is extended upward from the shortest length (the length when pushing). Thereby, by making the length of the hand-pushing portion 32 longer than before extending the length of the hand-pushing portion 32, the force when pulling the hand-pushing portion 32 backward and downward can be reduced.

[0045] Next, when holding the rear wheel 12R at a height above a predetermined height at which it is lifted, for example, when the rear plate 30 is inclined at a height above a predetermined level, a latch (not shown) provided on the rear plate 30 may protrude so that the protruding latch engages with the housing 18. Thereby, the rear wheel 12R can be held at a height above a predetermined height at which it is lifted. The release of the latch will be described later.

[0046] Also, as a specific example, the case where at least one rear wheel 12R has come off the road into a side ditch or the like has been described. However, for example, even when at least one front wheel 12F has come off the road, it is possible to escape from the derailment according to the embodiments of the present invention.

[0047] Specifically, for example, when the front wheel 12F comes off the wheel, the front wheel 12F that has come off is at a lower position than the rear wheel 12R, and the rear wheel 12R located diagonally to the front wheel 12F that has come off is at a height above a predetermined level from the ground, and the wheelchair 10 tilts. At this time, by pulling the push handle 32 downward and backward, the rear wheel 12R can be brought into contact with the ground from a height above a predetermined level from the ground. As a result, the front wheel 12F that has come off can be lifted to a height above a predetermined level.

[0048] Next, in order to move the lifted front wheel 12F from the wheel-off position, the push handle 32 is operated in the direction in which the front wheel 12F exits from the wheel-off position. As a result, the auxiliary wheel 33 in contact with the ground rotates, and the front wheel 12F can be moved from the wheel-off position. As a result, the wheelchair 10 can be moved.

[0049] In another embodiment, for example, the auxiliary wheel 33 is an all-direction wheel as an example. In this case, when the push handle 32 is moved in the direction of exiting from the wheel-off position, the driver or caregiver can move it in a direction that is easy to move in the front-rear, left-right, or rotational directions.

[0050] FIG. 3 is an exemplary and schematic perspective view showing the configuration of internal components of the wheelchair 10 according to the embodiment.

[0051] As shown in FIG. 3, the handle 24 is rotatably connected to a steering shaft 50 that extends downward from the center of the handle 24. A bracket 51 is attached to the lower part of the steering shaft 50, and a link 52 is swingably connected via the bracket 51. The link 52 swings in a manner capable of changing the traveling direction of the front wheel 12F. The bracket 51 has a rearward extending portion 54 that extends rearward.

[0052] For example, when the driver steers the handle 24, a pair of left and right links 52 swing via a bracket 51 fixed to the steering shaft 50. The pair of left and right links 52 swing in a manner capable of changing the traveling direction of the front wheel 12F.

[0053] When the front wheel 12F is facing the straight-ahead direction, the steering angle of the steering wheel 24 is set to 0 degrees. The position of the steering wheel 24 at 0 degrees is set as the center position of the steering wheel angle.

[0054] Next, the holding mechanism of the front wheel 12F when the rear wheel 12R is lifted will be described.

[0055] The front part of the rear plate 30 has a wire 40 extending forward, and the rearward extending part 54 of the bracket 51 is connected via the wire 40. The front part of the rear plate 30 tilts upward when the footrest part 31 or the hand push part 32 is operated (pressed) by the driver or the caregiver. In conjunction with this, the wire 40 is pulled rearward (in the direction of arrow A3).

[0056] When the bracket 51 is pulled rearward (in the direction of arrow A4 when the steering wheel is in the turning position) in conjunction with the wire 40, the steering shaft 50 is rotated. As a result, the link 52 swings, and the direction of the front wheel 12F becomes the straight-ahead direction.

[0057] Specifically, for example, when the front wheel 12F is turning from the straight-ahead direction to the turning direction at the position where the wheel has come off, the rear plate 30 tilts when the hand push part 32 or the footrest part 31 is operated (pressed) by the driver or the caregiver. When the rear plate 30 tilts, the wire 40 is pulled rearward.

[0058] When the bracket 51 is pulled rearward in conjunction with the wire 40, the direction of the front wheel 12F can be set to the straight-ahead direction via the link 52. As a result, when the wire 40 is being pulled rearward during wheel-off escape, the direction of the front wheel 12F can be held in the straight-ahead direction.

[0059] That is, when the front wheel 12F has come off, since the front wheel 12F is held in the straight-ahead direction, for example, when escaping through a groove or a depression, it is possible to suppress the front wheel 12F from turning arbitrarily compared to the case where the front wheel 12F is not held.

[0060] Next, the configuration of the wire 40 will be described. The wire 40 includes a wire base portion 41 between the bracket 51 and the rear plate 30. The wire base portion 41 has a front guide roller 42 and a rear guide roller 43. The front guide roller 42 and the rear guide roller 43 are fixed to the wire base portion 41, with the rear guide roller 43 being behind the front guide roller 42.

[0061] The front guide roller 42 has a pair of left and right rollers attached to the upper surface of the wire base portion 41, and the wire 40 is passed between the left and right rollers. The front guide roller 42 can reduce the lateral deflection of the wire 40 by the pair of left and right rollers and guide it in the straight - ahead direction.

[0062] The rear guide roller 43 has a roller attached to the upper surface of the wire base portion 41, and the wire 40 is passed between the wire base portion 41 and the roller. The rear guide roller 43 can reduce the vertical deflection of the wire 40 by the wire base portion 41 and the roller and guide it in the straight - ahead direction.

[0063] Note that a part of the wire 40 may be a spring or the like made of an elastic body. Thereby, an adjustment range can be ensured for the length of the wire 40.

[0064] Next, the operator provided on the upper part of the push - handle portion 32 will be described. The push - handle portion 32 includes a latch release portion (lever) 34, a front - wheel stopper portion (lever) 35, and a front - wheel stopper release portion (button) 36.

[0065] The latch release portion (lever) 34 is held by a latch at a predetermined height or more at which the rear wheel 12R is lifted. In this case, when the latch release portion (lever) 34 is operated (gripped), the latch can be pulled from the protruding position. Thereby, the latch can be released, and the rear wheel 12R can be lowered from the lifted height.

[0066] The front wheel stopper part (lever) 35 is such that when the driver or caregiver operates (holds) the lever, a stopper 53 provided on the outer periphery of the front wheel 12F clamps the front wheel 12F. Thereby, rotation of the front wheel 12F can be prevented.

[0067] Specifically, for example, when the wheelchair derails on an inclined road such as a downhill slope, if the rear wheel 12R is lifted, the front wheel 12F may rotate in the downward direction. Therefore, before lifting the rear wheel 12R, the front wheel stopper part (lever) 35 is operated.

[0068] Thereby, the stopper 53 clamps the front wheel 12F and can prevent rotation of the front wheel 12F. As a result, even when the rear wheel 12R is lifted, rotation of the front wheel 12F in the downward direction can be prevented.

[0069] The front wheel stopper release part (button) 36 can release the stopper 53 when operated (pressed). Thereby, by releasing the stopper 53 from the position where the front wheel 12F is clamped to prevent rotation of the front wheel 12F by operating the front wheel stopper part (lever) 35, the front wheel 12F can be made rotatable.

[0070] (Function and effect of this embodiment) As described above, the electric wheelchair 10 according to this embodiment has, for example, a rear plate 30 rigidly connected to the rear wheel 12R, a handrail part 32 extending upward from the rear plate 30, and an auxiliary wheel 33 pivotally supported by the rear plate 30 and capable of changing direction. When the handrail part 32 is operated, the auxiliary wheel 33 serves as a fulcrum and the rear plate 30 is tilted, whereby the rear wheel 12R is lifted. According to this, for example, when derailment occurs, by operating the handrail part 32, the auxiliary wheel 33 serves as a fulcrum and the rear wheel 12R can be lifted. As a result, at the position where the rear wheel 12R is lifted, by rotating the auxiliary wheel 33 in the moving direction of the electric wheelchair 10, it is possible to escape from derailment.

[0071] Further, the electric wheelchair 10 according to the embodiment of the present invention may have, for example, at least a depressible footrest portion 31 provided on the rear plate 30. According to this, for example, when wheel detachment occurs, by operating the handrail portion 32 and the footrest portion 31, the force for lifting the rear wheel 12R can be dispersed between the handrail portion 32 and the footrest portion 31. As a result, the rear wheel 12R can be lifted with a small dispersed force.

[0072] Further, the electric wheelchair 10 according to the embodiment of the present invention may have, for example, a wire 40 connecting the rear plate 30 and the steering shaft 50, and when the wire 40 is pulled backward, the front wheel 12F may be directed in the straight-ahead direction by rotating the steering shaft 50. According to this, for example, when the rear plate 30 is tilted and the wire 40 is pulled, the steering shaft 50 can be rotated so that the front wheel 12F faces the straight-ahead direction. Thereby, when the wire 40 is being pulled, the front wheel 12F can be held in the straight-ahead direction, making it easier to escape from the detachment location.

[0073] Further, in the electric wheelchair 10 according to the embodiment of the present invention, for example, the rear plate 30 may be connected to the rear wheel 12R via at least the vehicle body frame, the motor 14, or the drive shaft. According to this, for example, it is easier to attach the rear plate 30 later.

[0074] Further, in the electric wheelchair 10 according to the embodiment of the present invention, for example, the auxiliary wheel 33 may be an all-directional wheel that can move in the front-rear, left-right, or rotational directions. According to this, for example, when escaping from wheel detachment, the auxiliary wheel 33 can be moved in a direction that facilitates its escape.

[0075] As described above, the embodiments of the present invention have been explained, but the above-described embodiments are presented as examples and are not intended to limit the scope of the present invention. This novel embodiment can be implemented in various other forms. Also, without departing from the gist of the invention Within the scope, various omissions, replacements, and modifications can be made. Also, this embodiment is included in the scope and gist of the invention, and is included in the invention described in the claims and its equivalent scope.

Explanation of Reference Numerals

[0076] 10: Electric wheelchair 12F: Front wheel 12R: Rear wheel 30: Rear plate 31: Footrest 32: Push handle 33: Training wheel 40: Wire 50: Steering shaft​​

Claims

1. A rear plate rigidly connected to the rear wheel; A push portion extending upward from the rear plate; a turnable auxiliary wheel pivotally supported on the rear plate; When the push unit is operated, the auxiliary wheels become a fulcrum and the rear plate is tilted, thereby lifting the rear wheels. Electric wheelchair.

2. and at least a depressable footrest provided on the rear plate.

2. The electric wheelchair according to claim 1.

3. a wire connecting the rear plate and a steering shaft, When the wire is pulled rearward, the steering shaft is rotated to point the front wheels in a straight line.

2. The electric wheelchair according to claim 1.

4. The rear plate is connected to the rear wheel via at least a vehicle body frame, a motor, or a drive shaft.

2. The electric wheelchair according to claim 1.

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