JP7344507B2 - Wheelchair drive assist mechanism - Google Patents

Description

The present invention relates to a drive assist mechanism for a wheelchair.

Conventionally, wheelchairs equipped with various drive assist devices have been proposed as an intermediate between manual wheelchairs and electric wheelchairs. For example, Patent Document 1 discloses, for the purpose of providing a wheelchair equipped with a drive assist device that solves the problem of rotation in an undesired drive direction and the opposite direction due to a force caused by a downhill slope, a drive motor, a detection means, and a wheelchair. In the drive assist device for a wheelchair having a control unit, the detection means is configured to detect a force manually applied to the drive wheel, and the control unit is configured to detect the drive force manually applied to the drive wheel by the drive motor. and the control unit includes an anti-rollback operation mode to control the drive motor to avoid unintended rotation of the drive wheel. ing.

Japanese Patent Application Publication No. 2010-57901

However, in wheelchairs equipped with conventional drive assist devices, detailed assistance is provided to supply the appropriate motor torque for the required speed within a range that can ensure safety, depending on the user's situation. The problem was that it was difficult to provide such services.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a drive assist mechanism that obtains as much assist force as the user needs in order to smoothly assist the user in using a wheelchair. .

MEANS TO SOLVE THE PROBLEM In order to achieve the said objective, this invention is understood by the following structure.
(1) A first aspect of the present invention is a drive assist mechanism for a wheelchair, which includes a motor that drives wheels of the wheelchair, and a rotation speed that is provided close to the motor and that obtains the rotation speed of the motor. a sensor and a control unit that controls the motor, the control unit acquiring the rotation speed of the motor from the rotation speed sensor and adjusting the motor torque according to the speed obtained from the acquired rotation speed. It is characterized by controlling.

(2) In the configuration of (1) above, the control unit controls the maximum speed of the wheelchair selected in the control unit and the maximum motor torque of the wheelchair selected in a predefined or separately provided operation section. A plurality of operation modes are set in combination with the above, and the motor torque is controlled according to the speed within the range of the maximum speed and the maximum motor torque set in each operation mode.

(3) In the configuration of (2) above, the control unit controls the motor torque to gradually increase as the speed of the wheelchair increases until the maximum motor torque is reached.

(4) In the configuration of (2) or (3) above, when the motor torque reaches the maximum motor torque, the control unit maintains or gradually maintains the motor torque until the wheelchair reaches the maximum speed. controlled so that it decreases to

(5) The configuration according to any one of (1) to (4) above, further comprising a one-way clutch provided on a wheel of the wheelchair, and when the one-way clutch is in a connected state, the one-way clutch transfers the motor torque of the motor to the The information is transmitted to the wheels, and when the wheelchair is in the disconnected state, the wheelchair can be used as a manual wheelchair.

(6) In the configuration according to any one of (1) to (5) above, the control unit further includes a seating sensor, and when the power switch is on, the control unit takes into account the information acquired by the seating sensor and Activate the component.

(7) In the configuration according to any one of (1) to (6) above, the control unit further includes a parking sensor, and when the power switch is on, the control unit takes into account the information acquired by the parking sensor and Activate the component.

According to the present invention, it is possible to provide a drive assist mechanism that obtains the amount of assist force required by the user in order to smoothly assist the user in using the wheelchair.

1 is a front perspective view of an example of a wheelchair to which a drive assist mechanism according to an embodiment of the present invention is applied; FIG. Similarly, it is a perspective view of the wheelchair seen from the back. FIG. 3 is an enlarged diagram illustrating the main parts of the drive assist mechanism from the back. FIG. 2 is a block diagram schematically showing the configuration of a drive assist mechanism. FIG. 2 is a configuration diagram of an operating section of the drive assist mechanism. It is a block diagram of a control unit box among drive assistance mechanisms. FIG. 2 is a configuration diagram of a battery box of the drive assist mechanism. It is a figure explaining the example of the operation mode of a drive assistance mechanism. It is a graph showing the relationship between speed and motor torque in each operation mode of the drive assist mechanism, where (a-1) is "low speed mode/motor torque: zero" and (a-2) is "low speed mode/motor torque: (a-3) is "low speed mode/motor torque: medium", (a-4) is "low speed mode/motor torque: strong", (b-1) is "medium speed mode/motor torque: zero" ”, (b-2) is “medium speed mode/motor torque: weak”, (b-3) is “medium speed mode/motor torque: medium”, (b-4) is “medium speed mode/motor torque: "Strong" operation mode.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, modes for carrying out the present invention (hereinafter referred to as "embodiments") will be described in detail based on the accompanying drawings. FIG. 1 is a perspective view of the wheelchair 10 seen from the front, FIG. 2 is a perspective view of the wheelchair 10 seen from the back, and FIG. 3 is an enlarged view of the main parts of the drive assist mechanism from the back. Note that the same elements are given the same reference numerals throughout the description of the embodiments.

(Embodiment)
Although details will be described later, as shown in FIGS. 1 to 3, the drive assist mechanism of the wheelchair 10 according to the present embodiment includes motors 32L, 32R that drive wheels 17L, 17R of the wheelchair 10, and motors 32L, 32R. It includes a rotation speed sensor that is provided adjacent to the motors 32L and 32R to obtain the rotation speed of the motors 32L and 32R, and a control unit 31L that controls the motors 32L and 32R. In order to smoothly assist the use of the wheelchair 10, the drive assist mechanism is configured to obtain the rotational speed of the motors 32L, 32R and control the motor torque according to the speed obtained from the obtained rotational speed. This allows the user to obtain as much assist force as he or she needs depending on the situation in which the user is placed. Note that the motor torque is more specifically embodied as the torque of the gear head shaft assembled to the motors 32L and 32R.

More specifically, the control unit 31L determines the maximum speed of the wheelchair 10 selected by the control unit 31L and the wheelchair selected by a predefined or separately provided operation unit 20 (including the case where it is a remote control 20). A plurality of operation modes are set in combination with the 10 maximum motor torques, and the motor torque is controlled according to the speed within the range of the maximum speed and maximum motor torque set in each operation mode. For example, the control unit 31L controls the motor torque to gradually increase as the speed of the wheelchair 10 increases from a stopped state until the set maximum motor torque is reached. On the other hand, when the motor torque reaches the maximum motor torque, the control unit 31L controls the motor torque to be maintained or gradually decreased until the wheelchair 10 reaches the maximum speed.

Furthermore, the drive assist mechanism according to the present embodiment may further include a one-way clutch provided on the wheels 17L, 17R of the wheelchair 10, and when the one-way clutch is in a connected state, the motor torque of the motors 32L, 32R is transferred to the wheels 17L, 17R. 17L and 17R, and when in the disconnected state, the wheelchair 10 can be used as a manual wheelchair. Further, the drive assist mechanism may further include a parking sensor 40 and a seating sensor 50 separately or in combination as a safety measure. Each component is activated in consideration of the information acquired by the sensor 50. The details of the wheelchair equipped with the drive assist mechanism and the drive assist mechanism will be described below.

(wheelchair)
First, the configuration of a wheelchair 10 equipped with a drive assist mechanism according to this embodiment will be explained using FIGS. 1 to 3. Note that the structural configuration of the wheelchair 10 itself is not limited to what is illustrated. The drive assist mechanism according to this embodiment is applicable to various types of wheelchairs 10.

As shown in FIGS. 1 and 2, the wheelchair 10 has a frame 11 extending from the front lower part to the rear upper part, and in the middle of the frame 11 there is a seat part 14 on which the user sits, a backrest 15, and an armrest 12 on which the user can rest his/her arms. is provided. A step 19 on which the user's feet are placed is arranged at the lower front end of the frame 11, and a grip 13 for a caregiver is provided at the upper rear end of the frame 11. Although not shown here, the grip 13 may be provided with a manual brake for use by an assistant.

An operating section 20 for operating the drive assist mechanism may be provided on the left side of the seating section 14 (although not shown in FIGS. 1 and 2, the configuration of the operating section 20 is shown in FIGS. 4 and 5). (will be explained later as a remote control 20). A seating sensor 50 is arranged inside the seating section 14 to detect whether the user is seated or not. For example, a limit switch can be used as the seating sensor 50, and is turned on/off depending on whether the user is seated or not. As will be described later, the seating sensor 50 can be used as one of the triggers for driving the drive assist mechanism. Note that the seating section 14 may be a power cushion whose cushion is controlled by operation of the operating section 20 (remote control 20).

The wheelchair 10 is supported as front wheels by a pair of left and right casters 16L, 16R that can freely change direction, and as rear wheels by a pair of left and right wheels 17L, 17R whose drive is assisted by a drive assist mechanism. Hand rims 18L and 18R are arranged on the outside of the wheels 17L and 17R so that the user can manually move the wheelchair 10 by himself or herself as a manual wheelchair. Moreover, a brake in which a parking sensor 40 is arranged is provided in front of the wheels 17L and 17R. For example, a limit switch can be used as the parking sensor 40, and is turned on/off by parking/cancelling. As will be described later, the parking sensor 40 can be used as one of the triggers for driving the drive assist mechanism.

Inside the wheels 17L, 17R, as shown in an enlarged view in FIG. Inside, 61L is supported by the motor 32L (behind the motor 32L). Note that a pair of crossed crossbars 70 are arranged between the support parts 60L and 60R in order to reinforce the suspension function.

The auxiliary drive units 30L, 30R have motors 32L, 32R disposed inside each, and the wheels 17L, 17R are connected to the motors 32L, 32R via one-way clutches (not shown) provided on the axles 61L, 61R. Connected. A one-way clutch is connected during forward rotation and disconnected during reverse rotation. As a result, when the one-way clutch is in the connected state, the motor torque of the motors 31L, 31R is transmitted to the wheels 17L, 17R, and when the one-way clutch is in the disconnected state, the transmission of the motor torque from the motors 31L, 31R is cut off, and the wheelchair 10 becomes usable as a manual wheelchair.

To explain the effect of providing a one-way clutch, when moving the wheelchair 10 forward, "wheel rotation speed ≧ motor rotation speed", and when moving the wheelchair 10 backward, "wheel rotation speed = motor rotation speed". Since the wheel rotation speed can be increased when the motor rotation speed is zero, the wheelchair 10 can be moved easily like a manual wheelchair. Here, even if the wheel rotation speed is increased, assistance will not be provided unless the motor rotation speed increases. Therefore, by applying a slight motor torque of, for example, 0.8 N, when the motor rotation speed is zero, the motor rotation speed can be increased. The number may be increased. By doing so, rotation speed sensors for the wheels 17L and 17R can be made unnecessary.

In addition to the motor 31L, the auxiliary drive unit 30L is provided with a control unit 31L that controls the drive auxiliary mechanism (the auxiliary drive unit 30L is hereinafter also referred to as a "control unit box"). In addition to the motor 32R, the auxiliary drive unit 30R is provided with a battery 31R that supplies power to the drive auxiliary mechanism (the auxiliary drive unit 30R is also referred to as a "battery box" hereinafter). Between the auxiliary drive section 30L and the auxiliary drive section 30R, and between the auxiliary drive section 30L and the operation section 20, a connecting tube 81 and a connecting tube 82 containing various signal cables are installed.

(Drive assist mechanism)
Based on the above configuration, details of the drive assist mechanism will be explained using FIGS. 4 to 9. FIG. 4 is a block diagram of the drive auxiliary mechanism, FIG. 5 is a block diagram of the operation section 20 (remote control 20), FIG. 6 is a block diagram of the auxiliary drive section 30L ("control unit box"), and FIG. , a configuration diagram of the auxiliary drive unit 30R (“battery box”) is shown, respectively. Moreover, FIG. 8 shows an example of the operation mode of the drive assist mechanism, and FIG. 9 shows the relationship between speed and motor torque in each operation mode.

As shown in FIG. 4, the drive auxiliary mechanism includes an operation section 20 (remote control 20), an auxiliary drive section 30L ("control unit box"), and an auxiliary drive section 30R ("battery box"). Furthermore, a parking sensor 40 and a seating sensor 50 may be provided. Further, the operation section 20 (remote controller 20) may be configured to be able to output DC5V, and this output can be used as a power source when the seating section 14 is used as a power cushion, for example, as described above.

The configuration and procedure for controlling the drive assist mechanism will be described in detail below with reference to FIGS. 5 to 9.

(input specifications)
The drive assist mechanism is equipped with various input means, and first, the operating section 20 (remote controller 20) is provided with a motor torque selection switch, as shown in FIG. Here, the motor torque selection switch is configured to be able to switch the motor torque to four levels: "zero", "weak", "medium", and "strong". The motor torque selection switch is constituted by a tact switch 3, for example.

Next, on the control board of the control unit box 30L, as shown in FIG. connection), a start/stop switch (tact switch 1) provided on the operation plate to operate the start/stop of the drive assist mechanism, and a speed selection switch (tact switch 2) also provided on the operation plate to select the speed of the wheelchair 10. It is provided. In addition, the driver L in the control unit box 30L (2 points: Hall signal input to obtain the rotation speed of the motor L (motor 17L in FIGS. 1 and 2; the same applies hereinafter) and the error signal input) and the driver in the battery box 30R. A terminal is provided for receiving signal input from R (two points: Hall signal input for obtaining the rotation speed of motor R (motor 17R in FIGS. 1 and 2; the same applies hereinafter) and error signal input).

Here, the Hall signal means a signal from a Hall sensor as a rotation speed sensor provided in the motors L and R (motors 32L and 32R in FIG. 3). The number of rotations of the motors L and R (motors 17L and 17R in FIGS. 1 and 2) is obtained from the Hall signal, and the speed of the wheelchair 10 is obtained from this number of rotations. In this embodiment, the rotation speed of the motor is approximately the rotation speed of the wheel, and there is a relationship of [motor rotation speed≦wheel rotation speed]. Further, the drivers L, R and the motors L, R may each be connected to a regenerative resistor.

Furthermore, the control board of the control unit box 30L may be provided with a terminal that receives input from the parking sensor 40 (limit switch 1) and seating sensor (limit switch 2) provided in the main body of the wheelchair 10. .

(output specifications)
The drive auxiliary mechanism is equipped with various output means. First, as shown in FIG. An LED 5 that lights up when the motor torque is "medium", an LED 7 that lights up when the motor torque is "strong", and an LED 8 that lights up when the voltage drops (charging drops) are provided. Further, the operation unit 20 (remote controller 20) may be provided with a USB type A female (or type C female) for outputting DC5V 1A power in order to supply power when a power cushion is provided on the seating portion 14, for example. . However, this power output may be provided in the control unit box 30L instead of the operation section 20 (remote controller 20).

As shown in FIG. 6, the control board of the control unit box 30L has a driver L (3 points: 3 operation mode settings. The operation modes will be described later ), LED 1 is turned on when activated by the start/stop switch, LED 2 is turned on when the speed selection switch is activated in "low speed mode", and LED 3 is turned on when the speed selection switch is activated in "medium speed mode". In addition, it also sounds a buzzer and alarm in case of an emergency.

In addition, as shown in FIG. 7, the control board of the control unit box 30L has a driver R (3 points: 3 operation mode settings. The operation modes will be described later) that controls the motor R that drives the wheel R in the battery box 30R. perform the necessary output.

(Driver specifications)
As shown in FIGS. 6 and 7 (DRV-L and DRV-R in the figures), the drivers L and R each receive 18V DC power from the control board of the control unit box 30L. As described above, the drivers L and R output pulses (rotation) of the Hall sensors of the motors L and R as Hall signals and various errors as error signals to the control board of the control unit box 30L.

Here, an example of the operation mode input to the drivers L and R will be described with reference to FIG. 8. FIG. 8 shows an example in which three digital points "I1", "I2", and "I3" are set as the operation modes.

The mode setting of the operation mode is set based on the combination of "speed mode: motor torque mode". The combination of "speed mode: motor torque mode" is created by combining the aforementioned "low speed mode/medium speed mode" and "motor torque 'zero/weak/medium/strong'". , "Low speed mode/Motor torque: Weak", "Low speed mode/Motor torque: Medium", "Low speed mode/Motor torque: Strong", "Medium speed mode/Motor torque: zero", "Medium speed mode/Motor torque: There are eight basic combinations: "weak", "medium speed mode/motor torque: medium", and "medium speed mode/motor torque: strong".

Based on these eight combinations, the operation mode "I1" is a case where the speed is set to medium speed mode, "Medium speed: zero", "Medium speed: weak", "Medium speed: medium", " Operation mode "I2", which is a mode in which "medium speed: strong" is "ON", is when the speed is set to low speed mode and medium speed mode, and "low speed: weak", "low speed: strong", "medium" Operation mode "I3", which is a mode in which "speed: low" and "medium speed: strong" are "ON", is when the speed is set to low speed mode and medium speed mode, and "low speed: medium", "low speed" This is a mode in which "Medium Speed: Strong", "Medium Speed: Medium", and "Medium Speed: Strong" are set to "ON".

(Control procedure <input>)
The control procedure regarding input is as follows. The battery of the battery box 30R is attached to and detached from the battery connection terminal of the control unit box 30L as follows. When the device changes from not being installed to being installed (power supply DC 18V connected), the start/stop switch (tact switch 1) becomes “ON”. When the device changes from installed to uninstalled (or the power drops), the speed mode at that time is saved and the device is stopped.

The limit switch 1 provided on the main body of the wheelchair 10 functions as a parking sensor 40, and is turned "OFF" when the parking brake is applied, and "ON" when the parking brake is released. When the parking brake is applied and becomes "OFF", the process shifts to "parking control", and when the parking brake is released and becomes "ON", the process shifts to "normal control". In addition, in the case of a disconnection or a poor contact, control is performed to turn it "OFF".

Further, the limit switch 2 provided on the main body of the wheelchair 10 functions as a seating sensor 50, and is turned "ON" when the user is seated, and turned "OFF" when the user is not seated. If the vehicle is not seated (OFF), the state shifts to "non-seating control", and if the vehicle is seated (ON), the mode shifts to "normal control". In addition, in the case of a disconnection or a poor contact, control is performed to turn it "OFF".

A start/stop switch (tact switch 1) provided in the control unit box 30L starts/stops the control unit box 30L. When the power is connected, the default state is "startup" and LED1 lights up. Each time the tactile switch 1 is pressed, the LED 1 switches from turning off when it is "stopped" to turning on when it is "starting". If an error occurs, the error is canceled by normally pressing the tact switch 1. In the "start" state, the output of the DC5V power source is started, and in the "stop" state, the output of the DC5V power source is stopped.

A speed mode is selected by a speed selection switch (tact switch 2) provided in the control unit box 30L. When tact switch 2 is turned on, it will start up in the speed mode it was in last time it was started, and the corresponding LEDs will turn on. Light. The default is "low speed mode", and each time the tact switch 2 is pressed, the "medium speed mode" and "low speed mode" are switched.

A motor torque mode is selected by a motor torque selection switch (tact switch 3) provided in the operation section 20. At startup, it starts with "zero" and LED4 lights up. Each time you press the tact switch 3, the motor torque mode changes from "zero" to "weak" to "medium" to "strong" to "zero" and the corresponding LED changes from LED4 to LED5 to LED6. ⇒ LED 7 ⇒ LED 4 ⇒... and lights up in sequence. The tact switch 3 can be switched between "stop" and "start" by pressing and holding it for 3 seconds or more.

(Control procedure <Individual control>)
When the parking brake of the parking sensor 40 (limit switch 1) is applied and is "OFF", it is set to "parking control". In this "parking control", DC 18V power is not supplied to drivers L and R.

When the seating sensor 50 (limit switch 2) is "OFF" when the seat is not seated, "non-seating control" is set. In this "non-seating control", 18V DC power is not supplied to the drivers L and R. After 10 minutes under "unseated control", it "stops" and shifts to "standby control".

When the "start" state, the "ON" state with the parking brake of the parking sensor 40 not applied, and the "ON" state with the seating sensor 50 seated, the "normal control" is set. In this "normal control", DC 18V power is supplied to the drivers L and R. In the initial state, the "speed mode" is already selected, the motor torque mode is "zero", and the operation mode is set. The mode setting is then updated in response to switching between the "motor torque mode" and the "speed mode." As described above with reference to FIG. 8, the mode settings are "I1", "I2", and "I3" as three digital points.

Control by the drive assist mechanism in each of the "I1", "I2", and "I3" operation modes will be described with reference to FIG. 9. FIG. 9 shows the pattern of motor torque applied by the drive assist mechanism according to the speed of the wheelchair 10, with "speed (km/h)" plotted on the horizontal axis and "motor torque (Nm)" plotted on the vertical axis. There is.

In Figure 9, (a-1) is "low speed mode/motor torque: zero", (a-2) is "low speed mode/motor torque: weak", and (a-3) is "low speed mode/motor torque: medium". ”, (a-4) is “low speed mode/motor torque: strong”, (b-1) is “medium speed mode/motor torque: zero”, (b-2) is “medium speed mode/motor torque: weak” '', (b-3) shows the control in the case of "medium speed mode/motor torque: medium", and (b-4) shows the control in the case of "medium speed mode/motor torque: strong".

Operation mode “I1” is (b-1) “Medium speed mode/motor torque: zero”, (b-2) “medium speed mode/motor torque: weak”, (b-3) “medium speed mode/motor The pattern is "Torque: Medium" and (b-4) "Medium Speed Mode/Motor Torque: Strong". The operation mode "I2" is (a-2) "low speed mode/motor torque: weak", (a-4) "low speed mode/motor torque: strong", (b-2) "medium speed mode/motor torque: (b-4) "Medium speed mode/motor torque: strong". The operation mode "I3" is (a-3) "Low speed mode/Motor torque: Medium", (a-4) "Low speed mode/Motor torque: Strong", (b-3) "Medium speed mode/Motor torque: (b-4) "Medium speed mode/motor torque: strong" pattern.

Here, the maximum speed in the low speed mode is set to 2.5 km/h, and the maximum speed in the medium speed mode is set to 5.0 km/h. Further, the motor torque "weak" is set to 2.6 Nm, the motor torque "medium" to 4.1 Nm, and the motor torque "strong" to 5.6 Nm.

Looking at the low speed mode, in any case of maximum motor torque, the drive assist mechanism controls the motor torque to gradually increase as the speed of the wheelchair 10 increases until it reaches the maximum motor torque. When the maximum motor torque is reached at a speed of 2.0 km/h, the motor torque is gradually reduced by the drive assist mechanism until it reaches the set maximum speed of 2.5 km/h. controlled to do so.

Also, looking at the medium speed mode, similarly, in the case of any maximum motor torque, the drive assist mechanism causes the motor torque to gradually increase as the wheelchair 10 increases in speed until it reaches the maximum motor torque. is controlled by. When the maximum motor torque is reached at a speed of 3.0 km/h, the drive assist mechanism maintains the motor torque up to a speed of 4 km/h, and then increases it to the set maximum speed of 5.0 km/h. The motor torque is controlled to gradually decrease until reaching this point.

In this way, the drive assist mechanism according to the present embodiment controls the motor torque to gradually increase in the period from the start of the operation in which the user requires assistance to before reaching the maximum speed, and also After the torque is reached, the motor torque that is no longer needed by the user is maintained or gradually reduced until the maximum speed is reached. Coupled with the fact that the user can change the maximum motor torque depending on the situation in which the wheelchair 10 is placed (road conditions, etc.), the drive assist mechanism smoothly assists the use of the wheelchair 10 and allows the user to use the wheelchair 10 as needed. can provide just as much assist power.

Although the present invention has been described above using the embodiments, it goes without saying that the technical scope of the present invention is not limited to the scope described in the above embodiments. It will be apparent to those skilled in the art that various changes or improvements can be made to the embodiments described above. Furthermore, it is clear from the claims that forms with such changes or improvements may also be included within the technical scope of the present invention.

10...Wheelchairs 17L, 17R: Wheels 20...Operation unit (remote control)
30L, 30R…Auxiliary drive unit (control unit box, battery box)
31L...Control unit 31R...Battery 32L, 32R...Motor 40...Parking sensor 50...Setting sensor 60L, 60R...Support part 61L, 61R...Axle 70...Cross bar

Claims (5)

A wheelchair drive assist mechanism,
a motor that drives wheels of the wheelchair;
a rotation speed sensor that is provided close to the motor and obtains the rotation speed of the motor;
A control unit that controls the motor,
The control unit acquires the rotation speed of the motor from the rotation speed sensor, and controls motor torque according to the speed obtained from the acquired rotation speed,
The control unit sets a plurality of operation modes based on a combination of a maximum speed of the wheelchair selected in the control unit and a maximum motor torque of the wheelchair selected in a predefined or separately provided operation section. ,
The mode settings for each operation mode are set based on the combination of speed mode and motor torque mode, respectively.
controlling the motor torque according to the speed within the range of the maximum speed and the maximum motor torque set in each of the operation modes,
The drive assist mechanism is characterized in that the control unit controls the motor torque to gradually increase as the speed of the wheelchair increases until the motor torque reaches the maximum motor torque. The control unit controls the motor torque so that when the motor torque reaches the maximum motor torque, the motor torque is maintained or gradually decreased until the wheelchair reaches the maximum speed. 1. The drive assist mechanism according to 1. Further comprising a one-way clutch provided on the wheel of the wheelchair,
3. The one-way clutch, when in a connected state, transmits the motor torque of the motor to the wheels, and when in a disconnected state, enables the wheelchair to be used as a manual wheelchair. Drive assist mechanism as described. Additionally equipped with a seating sensor,
The drive according to any one of claims 1 to 3, wherein the control unit starts each component in consideration of information acquired by the seating sensor when the power switch is on. Auxiliary mechanism. Also equipped with a parking sensor,
The drive according to any one of claims 1 to 4, wherein the control unit starts each component in consideration of information acquired by the parking sensor when the power switch is on. Auxiliary mechanism.