JP3600903B2 - Manual electric wheelchair - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a manual electric wheelchair that applies a driving force according to the magnitude of human power intermittently applied to a vehicle as auxiliary power to a wheel to rotate the wheel.
[0002]
[Prior art]
Conventionally, a manual electric wheelchair has been proposed as an intermediate between a manual wheelchair and an electric wheelchair. This manual electric wheelchair is designed to reduce the physical burden of a disabled rider by detecting the human power that is intermittently applied to the wheels and applying auxiliary power according to the human power to the wheels. According to this, the rider can operate as a manual wheelchair, and mental pain is alleviated.
[0003]
By the way, in such a manual electric wheelchair, since it may be used as a manual wheelchair without depending on auxiliary power, a clutch means for connecting / disconnecting power transmission from a drive source to a wheel is indispensable.
[0004]
[Problems to be solved by the invention]
However, in a manual electric wheelchair equipped with a pair of left and right auxiliary power units, it is necessary to provide a clutch means for each auxiliary power unit, and the left and right clutch means can be switched by a simple operation reliably and simultaneously. It is desirable to obtain.
[0005]
The present invention has been made in view of the above circumstances, and an object of the present invention is to reliably and simultaneously switch the clutch means provided in each of the pair of left and right auxiliary power units with a simple operation. It is to provide a manual electric wheelchair.
[0006]
In addition, it is desirable from the viewpoint of safety that the drive source is in an operable state after both the left and right clutch means are in the ON state.
[0007]
Accordingly, another object of the present invention is to provide a highly safe manual electric wheelchair.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, the present invention adds an input detection means for detecting human power intermittently applied to a pair of left and right wheels, and auxiliary power corresponding to the human power detected by the input detection means to the wheels. In the manual electric wheelchair including a pair of left and right auxiliary power units that rotationally drive the clutch, each auxiliary power unit is provided with clutch means for connecting and disconnecting power transmission from the drive source to the wheels, and the left and right clutch means are provided as a single unit. Each of the clutch means is provided with a clutch detection means for detecting ON / OFF of the clutch means, and each of the driving is performed only when both the left and right clutch means are ON by the clutch detection means. The power source is configured to be operable .
[0010]
[Action]
According to the present invention, since the left and right clutch means are configured to be switched at the same time with a single lever, the power transmission from the drive source to the left and right wheels can be reliably performed with a simple operation.
[0011]
Further, according to the present invention, since the drive source can be operated after it is confirmed by the left and right clutch detection means that both the left and right clutch means are ON, abnormal operation such as abnormal turning is prevented and safety is ensured. The improvement of the property is achieved.
[0012]
【Example】
Embodiments of the present invention will be described below with reference to the accompanying drawings.
[0013]
FIG. 1 is a side view of a manual electric wheelchair as one embodiment of an auxiliary power vehicle according to the present invention, FIG. 2 is a front view of the wheelchair, FIG. 3 is a rear view showing a state in which the wheelchair is folded, and FIG. FIG. 5 is an enlarged fragmentary plan view, FIG. 6 is a cross-sectional view showing the configuration of the dog clutch unit, and FIG. 7 is an exploded perspective view of the dog clutch. 8 and 9 are cross-sectional views for explaining the operation of the dog clutch, FIG. 10 is an outer side view of the wheel, FIG. 11 is an outer side view of the hub portion of the wheel, and FIG. 12 is a state of the spring of the input detection unit. FIG. 13 and FIG. 14 are sectional views for explaining the state of the spring of the detection unit when human power is applied.
[0014]
A manual electric wheelchair 1 according to the present embodiment is an assembly of an auxiliary power device (Power Assist System) to an existing folding manual wheelchair. As shown in FIG. Are supported by a pair of left and right casters 3 and wheels 4.
[0015]
A cloth sheet 5 (see FIG. 2) to be seated by the rider is stretched at the center of the frame 2. The frame 2 has a pair of front and rear cross members 2 a, and the two cross members 2 a forming an X shape are pivotally connected to each other by a shaft 6. Therefore, the wheelchair 1 can be folded as shown in FIG. 3, and the seat 5 is also bent at this time.
[0016]
Further, a pair of left and right handle arms 2b are erected on the rear part of the frame 2, and the upper end of each handle arm 2b is bent rearward, and a grip 7 for an assistant is attached to the bent part. ing.
[0017]
A pair of left and right armrests 8 for the rider is attached to the center upper part of the frame 2, and a pair of left and right steps 9 are attached to the lower part of the front end of the frame 2. Further, another arm 2d is fitted to the lower end of the pair of left and right arms 2c extending in the front-rear direction at the lower part of the frame 2 so as to be movable in the front-rear direction. A roller 10 is rotatably supported on the shaft. The arm 2d is supported so as to be movable in the front-rear direction by engaging with a pin 11 protruding from the arm 2c, and this is always supported by a spring (not shown) that is retracted between the arm 2c. It is energized backward.
[0018]
By the way, as shown in FIGS. 4 and 5, each of the pair of left and right wheels 4 is rotatably supported by ball axles 14 and 15 on an axle 13 supported by a bracket 12 attached to the frame 2. On the outside of each wheel 4, a ring-shaped hand rim 16 on which the rider should turn this by hand is provided. The hand rim 16 is attached to a disc-shaped disk 18 rotatably supported by a bearing 17 on the hub 4 a of the wheel 4 via three spokes 19. Therefore, the hand rim 16 is attached to the wheel 4. Can rotate independently. In this embodiment, as shown in FIGS. 4 and 5, a damper 20 is interposed between the hub 4 a of the wheel 4 and the disk 18.
[0019]
Thus, the hand rim 16 is elastically connected to the wheel 4 at the three locations on the entire circumference by the structure shown in FIG.
[0020]
That is, as shown in FIG. 11, a spring guide 21 having an arcuate groove 21a is accommodated in a space between each pair of ribs 4a-1 formed on the hub 4a of the wheel 4, and the spring The guide 21 houses springs 22 and 23 having different diameters. In FIG. 11, reference numeral 24 denotes a holding member that prevents the springs 22 and 23 from falling off.
[0021]
Incidentally, both ends of the springs 22 and 23 are received by spring receivers 25 and 26. In a neutral state where no manual force is applied to the hand rim 16, the spring receivers 25 and 26 are shown in detail in FIG. The small-diameter spring 23 abuts against the pair of ribs 4a-1 and is compressed with a predetermined preload between the spring receivers 25 and 26, while the large-diameter spring 22 has both ends from the spring receivers 25 and 26. The spring receivers 25 and 26 are not exerted force by separating slightly. The spring constant of the large diameter spring 22 is set larger than that of the small diameter spring 23.
[0022]
On the other hand, as shown in FIG. 10, a pair of pins 27, 28 project inwardly at three locations on the entire circumference of the disk 18, and each pair of pins 27, 28 has a human power on the hand rim 16. In the neutral state where the spring is not applied, as shown in FIGS. 11 and 12, the spring receivers 25 and 26 are in contact with the end faces. One pin 27 is fixedly provided on the inner surface of the disk 18, while the other pin 28 is provided in an arc-shaped long hole 18 a formed in the disk 18 so as to be adjustable in position as shown in FIG. 11. The pin 28 is fixed to the disk 18 by being tightened by a nut 29 in contact with the end face of the spring receiver 26. The rib 4a-1 is formed with a groove 4a-2 for allowing the pins 27 and 28 to move.
[0023]
4 and 5, a potentiometer 30 for detecting the magnitude and direction of the human force applied to the hand rim 16 is fixed to the disk 18 on the hand rim 16 side. One end of a lever 31 is attached to the end of the manpower shaft 30a, and the other end of the lever 31 is engaged with a pin 32 protruding from the hub 4a of the wheel 4 via a rubber cap 33. doing. The cap 33 is used to prevent the lever 31 from rattling.
[0024]
Incidentally, as shown in FIGS. 4 and 5, an auxiliary power unit (only one is shown in FIGS. 4 and 5) 40 is provided inside each of the pair of left and right wheels 4.
[0025]
The auxiliary power unit 40 includes a drive motor 41 that generates auxiliary power and a gear case 42 that houses gears G1 to G4 that transmit the driving force of the drive motor 41 to the wheels 4. A small-diameter gear G1 is bound to the shaft end.
[0026]
Further, a counter shaft 43 and a drive shaft 44 are rotatably supported in parallel with the axle 13 on the gear case 42, and gears G 2 and G 3 having different diameters are connected to the counter shaft 43. A large-diameter gear G4 is supported so as to freely rotate, and a small-diameter gear G5 is attached to the end thereof. The large-diameter gear G2 meshes with the small-diameter gear G1, and the small-diameter gear G3 meshes with the large-diameter gear G4. The gear G5 meshes with a large-diameter ring gear G6 fitted and held on the inner periphery of the hub 4a. The ring gear G6 is held so as to be rotatable relative to the hub 4a, and a plurality of damper members 45 arranged in the circumferential direction are interposed therebetween.
[0027]
Meanwhile, a dog clutch 46 for connecting and disconnecting the large-diameter gear G4 with the drive shaft 44 is provided on the drive shaft 44. The dog clutch 46 is a clutch provided at the front upper portion of the frame 2. The lever 47 (see FIG. 1) is turned ON / OFF by a turning operation. A limit switch 48 for detecting ON / OFF of the dog clutch 46 is provided in the vicinity of the dog clutch 46 so that no current flows through the drive motor 41 when the dog clutch 46 is in the OFF state. .
[0028]
Details of the configuration of the dog clutch 46 will be described with reference to FIGS. 6 and 7.
[0029]
A disk-shaped dog 49 is supported on the drive shaft 44 so as to be rotatable and laterally movable. The dog 49 engages with and disengages from the three circular holes 50 formed in the gear G4. Three engagement pins 51 are projected. The dog 49 is biased by a spring 52 in a direction in which the engagement pin 51 is detached from the circular hole 50 of the gear G4 (to the right in FIG. 6).
[0030]
Further, the drive shaft 44 is formed with a circular hole 44a at the center of the shaft and a long hole 44b that is long in the lateral direction communicating with the circular hole 44a. A key 63 is inserted into the elongated hole 44b of the drive shaft 44, and the key 63 is engaged with a groove 49a (see FIG. 7) formed in the dog 49. Therefore, the drive shaft 44 and the dog 49 are connected in the rotational direction by the key 63, and both rotate integrally.
[0031]
On the other hand, a bracket 53 is attached to the gear case 42, and a guide sleeve 54 is coaxially connected to the bracket 53 with the drive shaft 44. A bottomed cylindrical plunger 55 is slidably fitted in the guide sleeve 54, and the plunger 55 is urged by a spring 56 to abut one end of a lever 57.
[0032]
By the way, the lever 57 is pivotally attached to the bracket 53 by a shaft 58, and the other end is connected to the clutch lever 47 (see FIG. 1) by a wire 59.
[0033]
A rod 60 is slidably fitted in a circular hole 44 a formed in the drive shaft 44 and the plunger 55, and the rod 60 is urged by the spring 56, and one end of the rod 60 is interposed via the ball 61. The other end of the rod 60 is provided with a retaining pin 62 that passes through a long hole 55a formed in the plunger 55.
[0034]
In addition, although the above described the structure of the auxiliary power unit 40 and the dog clutch 46 provided on the one wheel 4 side, the structure of the auxiliary power unit 40 and the dog clutch 46 provided on the other wheel 4 side is the same. A mass production effect can be obtained by sharing parts. Therefore, the pair of left and right auxiliary power units 40 are arranged in a point-symmetric relationship as shown in FIG. That is, in each auxiliary power unit 40, the drive motor 41 is offset from the center line of the axle 13, and such a common auxiliary power unit 40 is arranged in a point-symmetric relationship with respect to the left and right wheels 4. Then, the pair of left and right drive motors 41, which are the most convex portions of the present embodiment, are arranged with a step in the vertical direction, and the drive motors 41 interfere with each other when the wheelchair 1 is folded as shown in FIG. As a result, the wheelchair 1 can be folded compactly.
[0035]
Here, the operation of the dog clutch 46 will be described with reference to FIGS. 6, 8 and 9.
[0036]
When the clutch lever 47 is set to the solid line position (OFF position) in FIG. 1, both the left and right dog clutches 46 are in the OFF state, and at this time, as shown in FIG. The pin 51 is detached from the circular hole 50 of the gear G4, and the left and right limit switches 48 detect that both of the dog clutches 46 are in the OFF state.
[0037]
Next, when the rider rotates the clutch lever 47 at the solid line position in FIG. 1 and sets it to the chain line position (ON position) in FIG. 1, the clutch lever 47 is locked in the ON state by a lock mechanism (not shown). Then, the lever 57 is pulled by the wire 59 and rotated around the shaft 58 in the direction of the arrow (clockwise) in FIG. 6 to move the plunger 55 to the dog 49 side (left side in FIG. 8) as shown in FIG. Slide. Then, the spring 56 is compressed and its urging force is transmitted to the dog 49 via the rod 60, the ball 61 and the key 63, so that the dog 49 resists the urging force of the spring 52 on the drive shaft 44 side. As a result, the engagement pin 51 projecting from the dog 49 comes into a waiting state in contact with the end face of the gear G4.
[0038]
Thus, when the rider turns the hand rim 16 to drive the wheel 4 to rotate, the rotation of the wheel 4 is transmitted to the drive shaft 44 via the ring gear G6 (see FIG. 4) and the gear G5. Since the rotation of the engagement pin 51 projecting from the dog 49 matches the circular hole 50 of the gear G4, the engagement pin 51 engages with the circular hole 50 as shown in FIG. The dog clutch 46 is turned on. The ON state of the dog clutch 46 is detected by a limit switch 48.
[0039]
By the way, in the present embodiment, the drive motor 41 is configured to be operable only when both the left and right dog clutches 46 are ON by the limit switch 48. Here, FIG. 15 and FIG. 16 show circuit configuration examples for realizing this, respectively.
[0040]
In the example shown in FIG. 15, the left and right limit switches 48 (48L, 48R) and the main switch 64 are connected in series between the battery 80 and the controller 70, and both the left and right dog clutches 46 are in the ON state. left and right limit switches 48L, is possible energizes the drive motor 41 from the battery 80 through the controller 70 by the to Turkey oN only the main switch 64 when the 48R also are both oN.
[0041]
In the example shown in FIG. 16, the left and right limit switches 48 (48L, 48R) are connected in series between the battery 80 and the controller 70, and both the left and right dog clutches 46 are in the ON state. When both limit switches 48L and 48R are turned on, the drive motor 41 is energized from the battery 80 via the controller 70.
[0042]
Thus, when the release lever 47a shown in FIG. 1 is pushed, the lock mechanism (not shown) is released, and the clutch lever 47 returns to the OFF position by the urging force of the return spring (not shown). Then, the plunger 55 slides in the direction away from the dog 49 (rightward in FIG. 6) by the biasing force of the spring 56. Accordingly, the dog 49 also moves in the same direction on the drive shaft 44 by the biasing force of the spring 52. The engaging pin 51 protruding from the dog 49 is disengaged from the circular hole 50 of the gear G4 as shown in FIG. 6, and the dog clutch 46 is turned off. The OFF state of the dog clutch is detected by the limit switch 48.
[0043]
Here, the controller 70 will be described.
[0044]
As shown in FIG. 1, a controller 70 for controlling the driving of the auxiliary power unit 40 is attached to the front side of the frame 2, and a battery 80 is attached above the controller 70. . The controller 70 may be attached to the cross member 2a of the frame 2 as indicated by a chain line in FIG.
[0045]
The configuration of the controller 70 is shown in the block diagram of FIG. 17. The controller 70 includes an assist force calculation means 71 for calculating auxiliary power for human power applied to the hand rim 16 detected by the potentiometer 30, and the assist force calculation. Motor control means 72 for controlling the drive of the drive motor 41 (controlling the current to be supplied to the drive motor 41) with respect to the auxiliary power obtained by the means 71 (that is, the target value (target torque) of the auxiliary power); The gate drive circuit 73 is configured to receive a control signal from the motor control means 72 and to output gate signals G _a , G _b , G _c , G _d having corresponding duty values to the gate. In FIG. 17, 74a, 74b, 74c, and 74d are FETs (field effect transistors) that are turned ON / OFF by applying gate signals G _a , G _b , G _c , and G _d , respectively.
[0046]
Next, the operation of the manual electric wheelchair 1 will be described.
[0047]
When the user adds this to the force to turn the pair of right and left hand rims 16, for example, in the forward direction, until the magnitude of the human power F _M applied on each hand rim 16 overcomes the preload force of the three small diameter springs 23 In the meantime, the hand rim 16 does not move, and no relative rotation occurs between the hand rim 16 and the wheel 4. At this time, the output of the potentiometer 30 shows 0 as shown in FIG. Note that FIG. 18 is a diagram showing an output characteristic of the potentiometer 30 for the human power F _M applied to the hand rim 16, in the figure, F _M0 is the value of the human power is equal to the preload force of the three small diameter springs 23.
[0048]
Thereafter, when the human power F _M increases beyond F _M0, presses the one pin 27 is spring receiver 25 as shown in FIG. 13 is first compresses only small diameter spring 23, the compression amount of the hand rim 16 is spring 23 Rotate relative to the wheel 4 by an angle commensurate with. Then, the relative rotation of the hand rim 16 is transmitted is enlarged by the lever 31 to the potentiometer 30, the potentiometer 30, as shown in line a in FIG. 18, and outputs a signal to the human power F _M applied to the hand rim 16. Since the spring constant of the small diameter of the spring 23 small, the amount of compression against increase in manpower F _M of the spring 23, i.e., amount of rotation of the hand rim 16 is large, therefore, the sensitivity of the potentiometer 30 is kept high.
[0049]
When the value of the human power _{F M} applied to the hand rim 16 reaches _{F M1} shown in FIG. 18, the large diameter spring 22 also begins to be compressed together with the small diameter spring 23, the hand rim 16 to the compression amount of both springs 22 and 23 rotates relative angle by the wheel 4 to meet, at this time, the potentiometer 30 outputs a signal to the human power F _M applied to the hand rim 16 as indicated by the straight line b in FIG. 18.
[0050]
Thereafter, when the human power _{F M} applied to the hand rim 16 is greater than the _{F M2} shown in FIG. 18, the pin 27 as shown in FIG. 14 comes into contact with the holding member 24, the holding member from the human power _{F M} is pin 27 24 is transmitted directly to the wheel 4. At this time, the output of the potentiometer 30 is constant as shown by a straight line c in FIG.
[0051]
The output of the potentiometer 30 when the rider applies a reverse force to the hand rim 16 is represented by the straight lines a ′, b ′, and c ′ in FIG. 18, and the hatched areas in FIG. Become. By providing such a dead zone, it is possible to reliably detect the rest of the wheelchair 1 while allowing a mechanical error or an electrical error.
[0052]
And Thus, the hand rim 16 manpower F _M is applied intermittently, the human power F _M is detected by the potentiometer 30 as described above, the detection signal V _in input to the assist force calculation unit 71 of the controller 70 Is done.
[0053]
The assist force calculation unit 71 calculates a target torque τ based on the required assist ratio for an input signal V _in outputted from the potentiometer 30, and outputs a control signal commensurate therewith to the motor control unit 72. Incidentally, showing the relationship between the input signal V _in and the target torque τ (characteristic of the assist force calculation unit 71) in FIG. 19 the assist ratio as a parameter.
[0054]
The motor control means 72 controls the current to be supplied to the drive motor 41, and the gate drive circuit 73 receives the control signal from the motor control means 72 and converts the gate signals G _a and G _d having the necessary duty values to the FETs 74a and 74d. Apply to the gate (when moving forward). Then, the current from the battery 80 flows in the direction of the arrow in FIG. 17 through the FETs 74a and 74d, whereby the drive motor 41 is rotated forward. Current _{I b} through FET74d is fed back to the motor control unit 72 is compared with a target value, increases or decreases the gate signal _G a, a duty value of _{G d.}
[0055]
And Thus, the drive motor 41 as described above rotates forward, the driving force generated by the drive motor 41 is given to the wheel 4 as assist power F _A. That is, the rotation of the drive motor 41 is decelerated one step by the gears G1 and G2 shown in FIG. 5 and is transmitted to the counter shaft 43. Is decelerated by two stages and transmitted to the drive shaft 44. After the rotation of the drive shaft 44 that is decelerated three stages by the gear G5, G6, is transmitted to the wheels 4 via the damper member 45, the size of the wheel 4 is added auxiliary power F _A in the human power F _M Is driven to rotate by the driving force F (= F _M + F _A ), thereby causing the manual electric wheelchair 1 to move forward, and the rider has a small driving force (human power) F _M , for example, about 1/2 of the total driving force F. The wheelchair 1 can be operated easily.
[0056]
Meanwhile, when the human power _{F M} in the reverse direction (reverse direction) is applied to the hand rim 16, the gate drive circuit 73 shown in FIG. 17 is a gate signal _G b, these are applied respectively to _{G c} FET74b, to 74c Turn ON / OFF. Then, a current from the battery 80 is the drive motor 41 is reversed to flow through the drive motor 41 in the reverse direction, the direction of the auxiliary power F _A reversing this is added to the wheel 4. The motor current value _{I a} through FET74b is fed back to the motor control unit 72 is compared with a target value, increases or decreases the duty value of the gate signal _G b, _{G c.}
[0057]
As described above, in the present embodiment, the left and right dog clutches 46 are simultaneously switched by the single clutch lever 47, so that the power from the drive motors 41 of the left and right auxiliary power units 40 to the left and right wheels 4 is increased. The connection / disconnection of the transmission can be reliably performed with a simple operation.
[0058]
Further, according to the present embodiment, since the left and right limit switches 48 (48L, 48R) confirm that both the left and right dog clutches 46 are ON, the drive motor 41 can be operated. Abnormal operation is prevented and safety is improved.
[0059]
【The invention's effect】
As is apparent from the above description, according to the present invention, the left and right clutch means are configured to be switched at the same time with a single lever, so that it is easy to connect and disconnect the power transmission from the drive source to the left and right wheels. The effect that it can carry out reliably is acquired.
[0060]
Further, according to the present invention, since the drive source can be operated after it is confirmed by the left and right clutch detection means that both the left and right clutch means are ON, abnormal operation such as abnormal turning is prevented and safety is ensured. The effect that improvement of property is achieved is obtained.
[Brief description of the drawings]
FIG. 1 is a side view of a manual electric wheelchair according to an embodiment of the present invention.
FIG. 2 is a front view of a manual electric wheelchair according to an embodiment of the present invention.
FIG. 3 is a rear view showing a state in which a manual electric wheelchair according to an embodiment of the present invention is folded.
FIG. 4 is a cutaway plan view of a wheel portion showing an input detection unit and an auxiliary power unit unit of a manual electric wheelchair according to an embodiment of the present invention.
FIG. 5 is an enlarged cutaway plan view of a wheel portion showing an input detection unit and an auxiliary power unit unit of a manual electric wheelchair according to an embodiment of the present invention.
FIG. 6 is a cross-sectional view showing a configuration of a dog clutch portion.
FIG. 7 is an exploded perspective view of a dog clutch.
FIG. 8 is a cross-sectional view for explaining the operation of the dog clutch.
FIG. 9 is a cross-sectional view for explaining the operation of the dog clutch.
FIG. 10 is an outer side view of a wheel of a manual electric wheelchair according to an embodiment of the present invention.
FIG. 11 is an outer side view of a hub portion of a wheel of a manual electric wheelchair according to an embodiment of the present invention.
FIG. 12 is a cross-sectional view for explaining a state of a spring of the input detection unit.
FIG. 13 is a cross-sectional view for explaining the state of the spring of the detection unit when human power is applied.
FIG. 14 is a cross-sectional view for explaining the state of the spring of the detection unit when human power is applied.
FIG. 15 is a diagram illustrating a configuration example of a power supply circuit to a drive motor.
FIG. 16 is a diagram illustrating a configuration example of a power supply circuit to a drive motor.
FIG. 17 is a block diagram illustrating a configuration of a controller.
FIG. 18 is a diagram illustrating an output characteristic of a potentiometer with respect to human power applied to a hand rim.
FIG. 19 is a diagram illustrating the relationship between the input signal and the target torque (characteristics of assist force calculating means) using the assist ratio as a parameter.
[Explanation of symbols]
1 Manually operated wheelchair 4 Wheel 30 Potentiometer (input detection means)
40 Auxiliary power unit 41 Drive motor (drive source)
46 Dog clutch (clutch means)
47 Clutch lever (lever)
48 Limit switch (Clutch detection means)

Claims (1)

An input detection means for detecting human power intermittently applied to the pair of left and right wheels, and a pair of left and right auxiliary power units for applying auxiliary power according to the human power detected by the input detection means to the wheels and rotationally driving them. In the manual electric wheelchair provided,
Each auxiliary power unit is provided with clutch means for connecting / disconnecting power transmission from the drive source to the wheels, and the left and right clutch means are configured to be switched simultaneously with a single lever . A manual electric wheelchair characterized in that clutch detection means for detecting ON / OFF is provided, and the drive sources can be operated only when both the left and right clutch means are ON by the clutch detection means. .

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