JP2015159985A - wheelchair - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wheelchair that can climb over steps with relative ease.SOLUTION: A wheelchair 1 comprises at least a pair of right and left main wheels 3, and travels when the main wheels 3 are rotated by human power. The wheelchair 1 comprises an electric assist device that generates power to rotate the main wheels 3 by a minute angle.

Description

  The present invention relates to a wheelchair for traveling by human power, and more particularly to a wheelchair capable of supplying auxiliary power when getting over a road surface level difference.

  Conventionally, as a wheelchair, a non-electric wheelchair is known that travels by rotating a pair of left and right main wheels with human power. This type of wheelchair needs to supply a large rotational torque to the main wheel when climbing over a step on the road surface. For this reason, for wheelchair users, a great deal of labor was required to overcome the steps.

  Patent Document 1 below proposes a wheelchair provided with a jack for lifting the vehicle body behind the main wheel. However, since the wheelchair of Patent Document 1 is equipped with a jack and its power, there is a problem that the vehicle weight and the manufacturing cost increase.

JP 2004-16768 A

  The present invention has been devised in view of the actual situation as described above, and has as its main object to provide a wheelchair that can easily get over a step.

  The wheelchair of the present invention is a wheelchair that has at least a pair of left and right main wheels, and that travels by rotating the main wheels with human force, and generates power to rotate the main wheels by a small angle. It is characterized by comprising.

  In the wheelchair of the present invention, it is desirable that the minute angle is less than 360 °.

  In the wheelchair of the present invention, the electric assist device includes a power supply unit, a drive unit that is driven by electric power from the power supply unit, and a transmission unit that transmits the power of the drive unit to the main wheel. desirable.

  In the wheelchair of the present invention, the drive unit includes a movable shaft that linearly moves, and the transmission unit includes a motion conversion unit that converts the linear motion of the movable shaft into a rotational motion and rotates the main wheel. Is desirable.

  In the wheelchair according to the present invention, the main wheel has a hub, and the hub is rotatably inserted outside the pipe-shaped axle via a bearing, and the movable shaft of the drive unit is the axle. It is desirable to extend in the hollow portion.

  In the wheelchair according to the aspect of the invention, it is preferable that the movable shaft has a protruding portion that penetrates the axle and extends outward, and the motion converting portion is connected to the protruding portion.

  In the wheelchair of the present invention, the movable shaft linearly moves in a first direction for rotating the main wheel by a minute angle and a second direction opposite to the first direction, It is desirable to include a one-way clutch that transmits only the linear motion of the movable shaft in the first direction to the main wheel while not transmitting the rotational force on the main wheel side to the drive unit side.

  The wheelchair of the present invention has at least a pair of left and right main wheels, and travels by rotating the main wheels with human power. The wheelchair of the present invention includes an electric assist device that generates power and rotates the main wheel by a small angle.

  Such a wheelchair can easily get over the step by driving the electric assist device and rotating the main wheel by a small angle when the main wheel contacts the step. Moreover, such an electric assist device can simplify the structure and reduce the weight and cost compared to a so-called electric wheelchair that always rotates the main wheel with an electric motor or the like.

It is a side view of the wheelchair of this embodiment. It is a rear view of the wheelchair of this embodiment. (A) is a side view of the wheelchair before the main wheel gets over the step, and (b) is a side view of the wheelchair after the main wheel gets over the step. It is a fragmentary sectional view of the electric assistant device of this embodiment. It is a fragmentary sectional view when the electric assist device of this embodiment generates motive power. It is the elements on larger scale of the protrusion part and movement conversion part of this embodiment.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
The side view of the wheelchair 1 of this embodiment is shown by FIG. As shown in FIG. 1, the wheelchair 1 of the present embodiment includes a main body frame 2, a main wheel 3, and an auxiliary wheel 4. The wheelchair 1 of the present invention normally travels by rotating the main wheel 3 with human power. Such a wheelchair 1 includes both a person who rides in the wheelchair (hereinafter sometimes referred to as an occupant) that rotates the main wheel 3 by himself / herself and a person who proceeds by being pushed by an attendant.

  The main body frame 2 forms a skeleton of a wheelchair. The main body frame 2 is made of, for example, a metal material.

  A pair of main wheels 3 are provided on the left and right sides of the main body frame 2. On the outer side of the main wheel 3, for example, an annular hand wheel 5 that is integrally fixed to the rim 6 is provided. During normal traveling, the occupant applies a rotational force to the main wheel 3 by turning the handwheel 5, for example.

  The auxiliary wheels 4 are, for example, caster wheels that are rotatably provided on the main body frame 2. The auxiliary wheel 4 is provided in front of the main wheel 3. The auxiliary wheel 4 has a smaller diameter than the main wheel 3, for example.

  FIG. 2 shows a rear view of the wheelchair 1. As shown in FIG. 2, the wheelchair 1 of the present invention includes an electric assist device 10 that generates power and rotates the main wheels 3 on both sides by a minute angle.

  The side view of the wheelchair 1 when getting over the level | step difference on a road surface is shown by Fig.3 (a) and (b). As shown in FIG. 3A, when the wheelchair 1 gets over the step d, the auxiliary wheel 4 arranged on the front side of the vehicle body gets over the step d, and then the main wheel 3 behind the auxiliary wheel 4 , Contact the step d.

  At this time, most of the body weight of the wheelchair and the weight of the passenger act on the main wheel 3. For this reason, when the main wheel 3 gets over the step d on the road surface, the occupant needs to supply a large rotational torque T to the main wheel 3.

  As shown in FIG. 3B, the wheelchair 1 of the present invention drives the electric assist device 10 (shown in FIG. 2) to rotate the main wheel 3 by a small angle when the main wheel 3 comes into contact with the step. As a result, part or all of the rotational torque T can be supplied and the step can be easily overcome.

  For example, it is sufficient for the electric assist device 10 to supply power for overcoming a step of about 5 to 10 cm. For that purpose, it is sufficient that the minute angle θ1 is, for example, less than 360 °.

  The minute angle θ1 is preferably less than 180 °, more preferably less than 120 °. As a result, the electric assist device 10 is effectively downsized. The minute angle θ1 is preferably 60 ° or more, more preferably 90 ° or more. Thereby, the wheelchair 1 can easily get over a step that can be encountered on a normal road surface.

  Such an electric assist device 10 is to rotate temporarily and at a minute angle. For this reason, the wheelchair 1 of the present invention can be simplified in structure and can be reduced in weight and cost as compared with a so-called electric wheelchair in which the main wheel is rotated by an electric motor or the like to perform normal traveling.

  As shown in FIG. 2, the electric assist device 10 according to the present embodiment is provided, for example, in a lower portion of a seat 7 on which an occupant sits.

  FIG. 4 shows a partial cross-sectional view of the axle 34, the main wheel 3, and the electric assist device 10 provided in the main body frame 2.

  As shown in FIG. 4, an axle 34 is fixed to the main body frame 2 so as to protrude to the outside of the vehicle. The axle 34 is, for example, a pipe having a hollow portion.

  The main wheel 3 includes a hub 33 provided at the center, a plurality of spokes 32 connected to the hub 33, an annular rim 6 (shown in FIG. 1) supported by each spoke 32, and an outer periphery of the rim 6. And a tire 8 provided on the vehicle.

  The hub 33 is rotatably inserted on the outside of the axle 34 via a bearing 35. Thereby, the main wheel 3 is supported rotatably with respect to the axle 34 and the main body frame 2. Each spoke 32 extends from the hub 33 toward the radially outer side of the main wheel 3. As shown in FIG. 1, the outer end of each spoke 32 is connected to the inner peripheral surface of the rim 6.

  As illustrated in FIG. 4, the electric assist device 10 includes, for example, a power supply unit 11, a drive unit 12, and a transmission unit 13.

  The power supply unit 11 and the drive unit 12 are provided, for example, on the vehicle inner side of the axle 34.

  The power supply unit 11 is for supplying power to the drive unit 12, and for example, a rechargeable storage battery or the like is employed.

  The drive unit 12 is driven by electric power from the power supply unit 11 to generate a force. For example, a motor that rotates and a solenoid that moves the movable shaft by the electromagnetic force of the excitation coil are preferably used as the drive unit 12. The drive unit 12 of the present embodiment uses, for example, a linear solenoid 15 that linearly moves the movable shaft 17 by the magnetic force of the excitation coil 16. Thereby, the structure of the electric assist device 10 is simplified, and an increase in the vehicle weight of the wheelchair is effectively suppressed.

  The linear solenoid 15 includes, for example, a cylindrical excitation coil 16 and a movable shaft 17 and a fixed shaft 14 inserted therein.

  The exciting coil 16 is formed by winding a coil winding. The excitation coil 16 generates magnetic force when supplied with power from the power supply unit 11.

  The fixed shaft 14 is formed in a substantially cylindrical shape, for example, and is fixed inside the exciting coil 16. The fixed shaft 14 is made of, for example, a ferromagnetic material such as iron. The fixed shaft 14 is excited by the magnetic force of the excitation coil 16 and attracts the movable shaft 17.

  The movable shaft 17 is provided closer to the main wheel 3 than the fixed shaft 14. The movable shaft 17 is inserted into the exciting coil 16 so as to be movable in the axial direction. The movable shaft 17 is, for example, a substantially cylindrical shape having the same diameter and the same core as the fixed shaft 14. The movable shaft 17 and the fixed shaft 14 are connected via, for example, a spring 18.

  The movable shaft 17 extends in the hollow portion along the axle 34, for example. The movable shaft 17 has a protruding portion 19 that penetrates the axle 34 and extends outward. The protruding portion 19 is connected to the transmission portion 13.

  FIG. 6 shows a partially enlarged view of the protruding portion 19 and the like. As shown in FIG. 6, a helical gear 20 is provided on the outer peripheral surface of the protruding portion 19. The helical gear 20 extends obliquely with respect to the axial direction of the movable shaft 17.

  As FIG. 4 shows, the transmission part 13 is provided in the axial direction outer side of the axle shaft 34, for example. The transmission unit 13 transmits the power generated by the drive unit 12 to the main wheel 3. The transmission unit 13 of the present embodiment includes, for example, a motion conversion unit 21. The motion converter 21 converts the linear motion of the movable shaft 17 into a rotational motion and rotates the main wheel 3.

  As shown in FIG. 6, the motion conversion unit 21 includes, for example, a helical gear 20 provided in the protruding portion 19 of the movable shaft 17 and an inner ring 23 provided with internal teeth that mesh with the helical gear 20. Yes.

  The transmission unit 13 includes, for example, a one-way clutch 22.

  The one-way clutch 22 includes an inner ring 23, an outer ring 24 that is concentric with the inner ring 23, and a transmission switching unit 25 that is disposed therebetween.

  The inner ring 23 is provided on the outer periphery of the protruding portion 19. In addition, the inner ring 23 is restrained in the axial direction of the movable shaft 17 by being supported by the outer ring 24 and the transmission switching unit 25. For this reason, the inner ring 23 rotates as the movable shaft 17 moves linearly.

  The outer wheel 24 is provided on the outer periphery of the inner wheel 23 and is fixed to the hub 33 of the main wheel 3 as shown in FIG.

  The transmission switching unit 25 is disposed between the inner ring 23 and the outer ring 24. For example, the transmission switching unit 25 transmits only rotation in one direction of the inner ring 23 to the outer ring 24. In addition, the transmission switching unit 25 does not transmit the rotation of the outer ring 24 in both directions to the inner ring 23.

  The operation of the wheelchair 1 of the present embodiment configured as described above will be described. FIG. 5 shows a cross-sectional view of the electric assist device 10 when the linear solenoid 15 is driven. As shown in FIG. 5, when the switch 26 is turned on and electric power is supplied from the power supply unit 11, the exciting coil 16 generates a magnetic force, and the fixed shaft 14 attracts the movable shaft 17. Thereby, the movable shaft 17 linearly moves in the first direction a to generate power. At this time, the spring 18 is compressed between the movable shaft 17 and the fixed shaft 14.

  As shown in FIG. 6, when the movable shaft 17 linearly moves in the first direction a, the inner ring 23 of the one-way clutch 22 rotates via the helical gear 20 of the protruding portion 19. The transmission switching unit 25 transmits the rotation of the inner ring 23 to the outer ring 24 when the movable shaft 17 linearly moves in the first direction a.

  As shown in FIG. 5, the outer wheel 24 transmits the rotation from the transmission switching unit 25 to the hub 33 and rotates the main wheel 3 by a minute angle.

  After the power is generated, when the power from the power supply unit 11 is interrupted, the movable shaft 17 is urged by the spring 18, moves linearly in the second direction b, and returns to the original state.

  As shown in FIG. 6, when the movable shaft 17 linearly moves in the second direction b, the transmission switching unit 25 does not transmit the rotation to the outer wheel 24 and causes the inner wheel 23 to idle. Thereby, the movable shaft 17 can return to the original state smoothly.

  Moreover, the transmission switching unit 25 is configured not to transmit the rotational force on the main wheel side to the drive unit 12 side. Therefore, the wheelchair 1 can travel without being influenced by the drive unit 12 not only when moving forward but also when moving backward.

  As shown in FIG. 2, the electric assist device 10 according to the present embodiment is operated by, for example, a switch input of an attendant who pushes a passenger or a wheelchair. Such an electric assist device 10 rotates the main wheel at an arbitrary timing of an occupant or an attendant. This further improves the operability of the wheelchair.

  A pair of electric assist devices 10 of the present embodiment are provided, for example, inside each main wheel 3. The electric assist devices 10 and 10 are, for example, electrically connected to each other and controlled so that the rotation amount and timing of the main wheels 3 are uniform.

  As mentioned above, although especially preferable embodiment of this invention was explained in full detail, this invention is not limited to said embodiment, It can deform | transform and implement in a various aspect.

1 Wheelchair 3 Main wheel 10 Electric assist device

Claims (7)

A wheelchair that has at least a pair of left and right main wheels, and that travels by rotating the main wheels with human power,
A wheelchair comprising an electric assist device for generating power and rotating the main wheel by a small angle.   The wheelchair according to claim 1, wherein the minute angle is less than 360 °.   The wheelchair according to claim 1, wherein the electric assist device includes a power supply unit, a drive unit that is driven by electric power from the power supply unit, and a transmission unit that transmits power of the drive unit to the main wheel. . The drive unit includes a movable shaft that moves linearly,
The wheelchair according to claim 3, wherein the transmission unit includes a motion conversion unit that converts a linear motion of the movable shaft into a rotational motion to rotate the main wheel. The main wheel has a hub;
The hub is externally attached to the outside of the pipe-shaped axle through a bearing so as to be freely rotatable.
The wheelchair according to claim 4, wherein the movable shaft of the drive unit extends in a hollow portion of the axle. The movable shaft has a protruding portion that penetrates the axle and extends to the outside.
The wheelchair according to claim 5, wherein the motion conversion unit is connected to the protruding part. The movable shaft linearly moves in a first direction for rotating the main wheel by a minute angle and a second direction opposite to the first direction,
5. The transmission unit includes a one-way clutch that transmits only the linear motion of the movable shaft in the first direction to the main wheel, but does not transmit the rotational force on the main wheel side to the drive unit side. The wheelchair in any one of thru | or 6.

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