Travel manipulator system of power-assisted vehicle and control method of the same

Abstract

To provide a travel manipulator system of a power-assisted vehicle capable of making operator's maneuverability better, and a control method of the same.SOLUTION: A travel manipulator system includes a manipulation input machine and a control unit. The manipulation input machine includes a manipulator. The control unit controls a rotating direction of electric wheels and a rotation speed difference between the electric wheels according to a tilting direction of the manipulator. The control unit rotates the electric wheels in a direction associated with the tilting direction of the manipulator. When the manipulator is tilted along a second coordinate axis associated with a fore-and-aft direction of a vehicle body, one and the other electric wheels are rotated at an equal speed. When the manipulator is tilted at a position deviated in a circumferential direction within a range of a predetermined angle from the second coordinate axis, the electric wheels are rotated so that the rotation speed of the electric wheel located on a deviated side will get relatively lower. When the manipulator is tilted at a position deviated in the circumferential direction beyond the range of the predetermined angle from the coordinate axis, a rotation command for the electric wheels is canceled.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a traveling operation device for an electric assist vehicle and a control method thereof.

Background Art

[0002] Conventionally, an electric assist vehicle having drive electric wheels provided at the lower part of a carriage has been known (see, for example, Patent Document 1).

[0003] In the electric assist vehicle described in Patent Document 1, electric wheels are installed on one side and the other side in the vehicle width direction at the front part of the vehicle body, and driven wheels are installed on one side and the other side in the vehicle width direction at the rear part of the vehicle body. Further, an operation box is disposed above the rear part of the vehicle body, and the operation box is provided with a substantially U-shaped operation handle for an operator who operates the electric assist vehicle to grip. Torque sensors are provided at the left and right attachment parts of the operation handle, and an input load from the operator is detected by the torque sensors. Detection results (detection signals) from the left and right torque sensors are input to a controller, and the controller outputs commands to the left and right electric wheels so as to generate an assist force corresponding to the detection values detected by the left and right torque sensors.

[0004] In the case of this electric assist vehicle, since an assist force corresponding to the pushing and pulling operation of the operation handle by the operator is generated by the left and right electric wheels, the straight-ahead operation and turning operation by the operator can be assisted by the left and right electric wheels. For this reason, the operator can operate the electric assist vehicle in a desired direction by applying only a relatively small pushing and pulling operation force to the electric assist vehicle.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, in the electric assist vehicle described in Patent Document 1, torques corresponding to the operating loads applied by the operator to the operation handle are detected by left and right torque sensors, and assist forces corresponding to the detection results by the left and right torque sensors are generated by the left and right electric wheels. Therefore, the operator has to firmly hold the operation handle with both hands and carefully apply a load to the operation handle (left and right torque sensors) so that the operation intention of the operator is reflected. Therefore, in the case of the electric assist vehicle described in Patent Document 1, it cannot be said that the usability of the traveling operation device is good, and it is desired to devise a traveling operation device with better operability.

[0007] Therefore, the present invention aims to provide a traveling operation device for an electric assist vehicle and a control method thereof that can improve the operability by the operator.

Means for Solving the Problems

[0008] In order to solve the above problems, the traveling operation device for an electric assist vehicle according to the present invention employs the following configuration. That is, the traveling operation device for an electric assist vehicle according to the first aspect of the present invention is a traveling operation device for an electric assist vehicle including a vehicle body, electric wheels disposed at least one on each of one side and the other side in the vehicle width direction of the vehicle body, and at least one driven wheel disposed on the vehicle body at a distance from the electric wheels in the longitudinal direction of the vehicle body, the traveling operation device having an operation input device having an operator that can be tilted in any direction around a tilting center, and a control unit that controls the rotation direction and the rotation speed difference between the electric wheel on one side in the vehicle width direction and the electric wheel on the other side in the vehicle width direction according to the tilting direction of the operator. Regarding the operator, when a rectangular coordinate system having a first coordinate axis corresponding to the vehicle width direction and a second coordinate axis corresponding to the longitudinal direction of the vehicle body is defined with the tilting center as the origin, the control unit determines the rotation direction of each electric wheel according to whether the tilting direction of the operator is on the front side or the rear side of the vehicle body with respect to the first coordinate axis. When the operator is tilted along the second coordinate axis, a command to rotate the electric wheel on one side and the electric wheel on the other side at the same speed is output to each electric wheel. When the operator is tilted at a position circumferentially shifted within a range of a predetermined angle from the second coordinate axis around the origin, a rotation command is output to each electric wheel such that the rotation speed of the electric wheel located on the shifted side becomes relatively slower than the rotation speed of the electric wheel located on the opposite side. When the operator is tilted at a position circumferentially shifted beyond the predetermined angle from the second coordinate axis around the origin, a command to rotate each electric wheel is canceled.

[0009] In the case of this traveling operation device, when the operator of the operation input device is tilted, the control unit controls the rotation direction, the rotation speed difference, and the on / off state of the electric wheels on one side and the other side in the vehicle width direction according to the tilting direction of the operator. That is, basically, when the operator is operated to the front side of the vehicle body, each electric wheel is rotationally driven in the direction of advancing the vehicle body, and when the operator is operated to the rear side of the vehicle body, each electric wheel is rotationally driven in the direction of retracting the vehicle body. At this time, when the operator is operated along the second coordinate axis, the electric wheels on one side and the other side in the vehicle width direction are driven at the same speed. The vehicle body thereby travels straight forward or backward. On the other hand, when the operator is tilted at a position circumferentially shifted within a predetermined angle range from the second coordinate axis around the origin, the electric wheel on the shifted side is driven at a rotational speed relatively slower than that of the electric wheel on the opposite side. As a result, the vehicle body turns in the tilting direction of the operator. Also, at this time, when the operator is tilted at a position circumferentially shifted beyond the predetermined angle from the second coordinate axis around the origin, the driving of both electric wheels is canceled. As a result, the assist by the electric wheels stops.

[0010] A second aspect of the present invention is the traveling operation device for an electric assist vehicle according to the first aspect, wherein when the operator is tilted at a position circumferentially shifted within the predetermined angle range from the second coordinate axis around the origin, the control unit controls the rotation of each electric wheel such that the rotational speed of the electric wheel located on the shifted side becomes relatively slower than the rotational speed of the electric wheel located on the opposite side in accordance with the degree corresponding to the circumferential shift angle.

[0011] In this case, when the operator is tilted at a position circumferentially shifted within a predetermined angle range from the second coordinate axis around the origin, the rotational speed of the electric wheel on the shifted side becomes relatively slower with the difference from the rotational speed of the electric wheel on the opposite side in accordance with the degree corresponding to the circumferential shift angle of the operator. As a result, the vehicle body turns in a desired direction in accordance with the degree corresponding to the circumferential shift angle of the operator from the second coordinate axis. Therefore, when this configuration is adopted, by the operator adjusting the shift angle from the second coordinate axis in the tilting direction of the operator, it becomes possible to easily and quickly adjust the turning state of the vehicle body.

[0012] A third aspect of the present invention is the traveling operation device for an electric assist vehicle according to the second aspect, wherein the driven wheel is a free wheel rotatably supported around an axis oriented in a substantially vertical direction, and the separation distance between the electric wheel and the driven wheel is longer than the separation distance between the electric wheel on one side in the vehicle width direction and the electric wheel on the other side in the vehicle width direction.

[0013] In this case, the driven wheels are free wheels that can rotate around an axis facing the substantially vertical direction, and the distance between the front and rear of the electric wheels and the driven wheels is longer than the distance between the electric wheels on one side and the other side in the vehicle width direction. From this, when the rotational speed difference between the electric wheels on one side and the other side in the vehicle width direction increases, it becomes difficult for the stable turning force due to the rotational speed difference to act on the vehicle body due to the wheel spin of one of the electric wheels. However, in the case of the traveling operation device of the electric assist vehicle of this aspect, the circumferential region of the operator that can be used for turning the vehicle body is limited to a range of a predetermined angle from the second coordinate axis. Therefore, when this configuration is adopted, it becomes possible to always apply a stable turning force to the vehicle body.

[0014] A fourth aspect of the present invention is characterized in that, in the traveling operation device of the electric assist vehicle according to the third aspect, the electric wheels and the driven wheels are respectively arranged one by one in the vicinity of the four corners on the outer sides in the vehicle width direction at the front and rear of the vehicle body.

[0015] In this case, the four corners of the vehicle body are stably supported by the electric wheels and the driven wheels. Further, since the two electric wheels are arranged sufficiently apart in the vehicle width direction of the vehicle body, it becomes easy to apply an assist force for stable turning to the vehicle body.

[0016] A fifth aspect of the present invention is characterized in that, in the traveling operation device of the electric assist vehicle according to the fourth aspect, when the operator is operated on the front side of the vehicle body with respect to the first coordinate axis, the predetermined angle is an angle shifted by 45° to the front side of the vehicle body around the origin with respect to the first coordinate axis, and when the operator is operated on the rear side of the vehicle body with respect to the first coordinate axis, the predetermined angle is an angle shifted by 45° to the rear side of the vehicle body around the origin with respect to the first coordinate axis.

[0017] In this case, the angular positions shifted by 45° to the front side and the rear side with respect to the first coordinate axis of the operator are the critical operation positions in the circumferential direction of the operator that can be used for turning the vehicle. Since the angular positions shifted by 45° to the front side and the rear side with respect to the first coordinate axis are angular positions that are easy for the operator operating the operator to grasp as a feeling, the operator can operate the operator for turning the vehicle body within a range of a predetermined angle without discomfort.

[0018] In the sixth aspect of the present invention, in the traveling operation device of the electric assist vehicle according to any one of the first to fifth aspects, the operator is operable to be pushed in, and when the operator is pushed in, the control unit is characterized by stepwise switching the output of the electric wheel.

[0019] In this case, by pushing in the operator, the operator can easily change the output of the electric wheel.

[0020] In the seventh aspect of the present invention, in the traveling operation device of the electric assist vehicle according to any one of the first to sixth aspects, a gripping portion for manually pushing and pulling the vehicle body in the traveling direction is provided on the vehicle body, and the operation input device is provided on the gripping portion.

[0021] In this case, when the operator grips the gripping portion, the operator can easily operate the operator with a fingertip or the like. Therefore, when manually pushing and pulling the vehicle body, the operator can easily obtain the assist force by the electric wheel even with one hand. Therefore, when this configuration is adopted, the operability of the assist vehicle becomes better.

[0022] A control method for a traveling operation device of an electric assist vehicle according to an aspect of the present invention is a control method for a traveling operation device of an electric assist vehicle according to any one of the first to seventh aspects, the method including: determining a tilting direction of the operator; and controlling a rotation direction of the electric wheel, a rotational speed difference between the electric wheel on one side and the electric wheel on the other side, and turning on / off of the output of the electric wheel according to a determination result of the determining step.

[0023] In this case, by incorporating a program for executing the above steps into the control unit, it becomes possible to easily obtain the assist force of the electric wheel according to the intention of the operator.

Advantages of the Invention

[0024] According to the present invention, the operability by the operator can be made better.

Brief Description of the Drawings

[0025]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Embodiments for Carrying Out the Invention

[0026] Next, embodiments of the present invention will be described with reference to the drawings.

[0027] <Electric assist basket cart> FIG. 1 is a perspective view of an electric assist basket cart 1 which is one form of an electric assist vehicle, and FIG. 2 is a plan view of the electric assist basket cart 1. In the following description, with respect to the vertical direction and the horizontal direction, it means the vertical direction and the horizontal direction in a state where the electric assist basket cart 1 is placed on the road surface R. As shown in FIG. 1, the electric assist basket cart 1 includes a loading platform 2, a handle 3 provided on the loading platform 2, a traveling operation device 4 provided on the handle 3, and drive wheels 5 and driven wheels 6 provided below the loading platform 2. The drive wheel 5 is driven by a motor 32 with a speed reducer, which will be described later. In this embodiment, the drive wheel 5 constitutes an electric wheel. Further, in this embodiment, the loading platform 2 constitutes the vehicle body of an electric assist cart.

[0028] The loading platform 2 includes a substantially rectangular parallelepiped frame body 7 that is long in one direction when viewed from above, and a basket main body 8 that is supported by being surrounded by the frame body 7. The basket main body 8 is formed of a deformable material such as a net, for example. Further, the basket main body 8 is formed in a substantially rectangular parallelepiped shape corresponding to the frame body 7 and has an opening 8a at the upper part. The frame body 7 is foldable such that the short side surfaces 8b on both sides in the longitudinal direction among the side surfaces of the basket main body 8 approach and separate from each other. Further, the frame body 7 is foldable such that the long side surfaces 8c on both sides in the short direction among the side surfaces of the basket main body 8 approach and separate from each other.

[0029] The handle 3 includes a support column 11 that extends upward from one end portion in the longitudinal direction of the frame body 7, and an annular grip portion 12 provided at the upper end of the support column 11. The user (operator) can move forward by pulling the electric assist basket cart 1 while holding the grip portion 12. The electric assist basket cart 1 can also be moved forward by the user (operator) pushing the electric assist basket cart 1 while holding the grip portion 12, but the pulling side of the electric assist basket cart 1 is set as the main traveling direction. Hereinafter, the side where the handle 3 is provided on the short side surface 8b will be described as the front in the traveling direction of the electric assist basket cart 1. The traveling direction coincides with the longitudinal direction of the basket main body 8.

[0030] Further, in the following description, the longitudinal direction of the loading platform 2 is referred to as the front-rear direction, and the short direction of the loading platform 2 orthogonal to the front-rear direction is referred to as the vehicle width direction. Among the vehicle width direction, the right side and the left side when looking at the front side may be simply referred to as the right side and the left side. In FIG. 1, the postures of the drive wheel 5 and the driven wheel 6 are the postures when the electric assist basket cart 1 travels straight forward or backward. When explaining the drive wheel 5 and the driven wheel 6, the explanation will be based on the posture when the electric assist basket cart 1 travels straight forward or backward.

[0031] The traveling operation device 4 is a device for operating the traveling of the vehicle body (electric assist basket trolley 1) by controlling the rotation of the left and right drive wheels 5. The traveling operation device 4 includes an operation input device 13 having a lever 15 as an operator, and a control unit 9 (see FIG. 5) that drives and controls the left and right drive wheels 5 according to the tilting direction of the lever 15. The control unit 9 is built into the housing 14 of the operation input device 13. However, the control unit 9 may be mounted on a part other than the housing 14. Details of the traveling operation device 4 will be described later.

[0032] Two drive wheels 5 and two driven wheels 6 are provided respectively. The drive wheels 5 and the driven wheels 6 are provided at the four corners of the lower part of the frame body 7. More specifically, the drive wheels 5 are provided at the rear and on both sides in the vehicle width direction of the lower part of the frame body 7. The driven wheels 6 are provided at the front and on both sides in the vehicle width direction of the lower part of the frame body 7. In this way, the distance between the drive wheels 5 and the driven wheels 6 arranged in the front-rear direction is set longer than the distance between the two drive wheels 5 arranged in the vehicle width direction and the distance between the two driven wheels 6.

[0033] The driven wheel 6 includes a driven bracket 21 rotatably and detachably provided on the frame body 7, a driven axle 22 rotatably supported by the driven bracket 21, and a driven wheel body 23 fixed to the driven axle 22. Since the configuration of the driven bracket 21 is the same as that of the drive bracket 31 described later, the description here is omitted. The driven wheel body 23 includes a wheel 24 fitted and fixed to the driven axle 22, and a tire 25 fitted to the outer peripheral surface of the wheel 24. The driven wheel 6 is a free wheel rotatably supported about an axis substantially in the vertical direction.

[0034] <Drive wheel (electric wheel)> The two drive wheels 5 have the same configuration and are arranged symmetrically about the center in the vehicle width direction. Therefore, in the following description, only the drive wheel 5 arranged on the left side among the two drive wheels 5 will be described, and the description of the drive wheel 5 arranged on the right side will be omitted.

[0035] Figure 3 is a perspective view of the left drive wheel 5 as viewed obliquely from the front. Figure 4 is a cross-sectional view taken along the rotation axis A1 of the drive wheel 5 shown in Figure 3. As shown in FIGS. 1 to 4, the drive wheel 5 includes a drive bracket 31 detachably provided on the frame body 7, a motor with a speed reducer 32 fixed to the drive bracket 31, a drive axle 33 supported by the motor with a speed reducer 32 and the drive bracket 31, and a drive wheel body 34 attached to the drive axle 33.

[0036] <Drive bracket> The drive bracket 31 includes a support column 35 that can be inserted into and removed from the frame body 7 in the vertical direction, and a bracket main body 36 integrally formed at the lower end of the support column 35. The bracket main body 36 is formed by bending a strip-shaped metal plate through pressing, and is formed in a U shape with an opening at the bottom. That is, the bracket main body 36 includes a top plate 37 and two side plates 38 and 39 (the first side plate 38 and the second side plate 39) that bend and extend downward from both sides of the top plate 37 in the vehicle width direction.

[0037] Among the two side plates 38 and 39, a through hole 38a that penetrates the first side plate 38 in the thickness direction is formed at the lower end of the first side plate 38 on the outer side in the vehicle width direction (the left side in FIGS. 3 and 4). The first end portion 33a of the drive axle 33 on the outer side in the vehicle width direction is inserted through the through hole 38a. A bearing unit 41 is provided on the outer surface 38b on the outer side in the vehicle width direction (the left side) at the lower end of the first side plate 38. The bearing unit 41 includes a bearing housing 42 fixed to the outer surface 38b of the first side plate 38 and a bearing 43 housed in the bearing housing 42. The first end portion 33a of the drive axle 33 inserted through the through hole 38a is rotatably supported by this bearing 43.

[0038] <Motor with a speed reducer> The motor 32 with a speed reducer is fixed to the second side plate 39 on the inner side in the vehicle width direction (the right side in FIGS. 3 and 4) of the two side plates 38 and 39 by bolts 49 via a mounting stay 50. The motor 32 with a speed reducer includes a case 51 fixed to the inner surface 39a on the outer side in the vehicle width direction of the second side plate 39, and an electric motor 52 and a speed reduction mechanism portion 53 housed coaxially with the rotation axis A1 in the case 51. Hereinafter, the direction parallel to the rotation axis A1 will be referred to as the axial direction, the rotation direction centered on the rotation axis A1 will be referred to as the circumferential direction, and the direction orthogonal to the axial direction and the circumferential direction will be referred to as the radial direction for explanation.

[0039] The case 51 is formed such that its outer diameter gradually decreases toward the outer side in the vehicle width direction (the first side plate 38 side). An opening 51a is formed on the inner side in the vehicle width direction (the second side plate 39 side) of the case 51. A cover 54 is attached to the case 51 so as to close the opening 51a.

[0040] As the electric motor 52, for example, an inner rotor type brushless motor is used. The electric motor 52 includes a stator 55 fixed to the opening 51a side of the case 51, a rotor 56 disposed on the inner side in the radial direction of the stator 55, and a control board 59 disposed on the inner side in the vehicle width direction of the stator 55 and the rotor 56. The electric motor 52 is covered by the cover 54 from above the control board 59.

[0041] The stator 55 includes a stator core 57 formed in an annular shape and a coil 58 wound around the stator core 57. The stator core 57 is fixed to the case 51 such that the outer peripheral surface of the stator core 57 is fitted to the inner peripheral surface of the case 51. The coil 58 is connected to the control board 59.

[0042] The rotor 56 includes a rotor shaft 64 rotatably supported on the case 51 and the speed reduction mechanism portion 53 via a first bearing 61, a second bearing 62, and a third bearing 63, a disk-shaped rotor core 65 fitted and fixed to the rotor shaft 64, and a permanent magnet 66 provided on the outer peripheral surface of the rotor core 65. The axis A3 of the rotor shaft 64 coincides with the rotation axis A1. The permanent magnet 66 faces the stator 55 in the radial direction.

[0043] On the control board 59, for example, a plurality of switching elements (not shown) and a sensor 67 for detecting the rotation angle of the rotor shaft 64 are mounted. The sensor 67 outputs the information on the detected rotation angle of the rotor shaft 64 as a signal. Further, a motor harness 71 and a sensor harness 72 (see FIG. 1) are connected to the control board 59.

[0044] The motor harness 71 is electrically connected to the coil 58. The sensor harness 72 is electrically connected to the sensor 67. These harnesses 71, 72 are drawn out to the outside via the case 51. A drive-side motor connector 73 (see FIG. 1) is connected to the end of the drawn-out motor harness 71. A drive-side sensor connector 74 (see FIG. 1) is connected to the end of the drawn-out sensor harness 72. These connectors 73, 74 are fixed to the drive bracket 31.

[0045] The speed reduction mechanism portion 53 is housed outside the electric motor 52 in the vehicle width direction in the case 51. For example, a so-called hypocycloid speed reduction mechanism is used for the speed reduction mechanism portion 53. The speed reduction mechanism portion 53 includes a rotation output portion 82 rotatably supported on the case 51 via a fourth bearing 81, and a plurality of gears 83 that reduce the rotation of the rotor shaft 64 and transmit it to the rotation output portion 82. Thereby, the rotation of the rotor shaft 64 is reduced and output by the rotation output portion 82.

[0046] The second end portion 33b of the drive axle 33 opposite to the first end portion 33a is fixed to the rotary output portion 82. More specifically, an outer flange portion 33c that projects radially outward is integrally formed on the second end portion 33b of the drive axle 33. A plurality of bolt insertion holes 84 penetrating in the axial direction are formed in the outer flange portion 33c. The bolt insertion holes 84 are arranged at equal intervals in the circumferential direction. A plurality of female screw portions 82a communicating with the bolt insertion holes 84 are formed in the rotary output portion 82.

[0047] Bolts 85 are respectively inserted into the bolt insertion holes 84 from above the outer flange portion 33c, and these bolts 85 are tightened to the female screw portions 82a. Thereby, the second end portion 33b of the drive axle 33 is fixed to the rotary output portion 82, and the drive axle 33 and the rotary output portion 82 are integrated. The first end portion 33a of the drive axle 33 is rotatably supported by the drive bracket 31 via a bearing 43. The second end portion 33b of the drive axle 33 is rotatably supported by the case 51 via the rotary output portion 82 and a fourth bearing 81.

[0048] <Drive wheel body> The drive wheel body 34 is provided between the speed reduction motor 32 and the first side plate 38 of the drive bracket 31 in the drive axle 33. The drive wheel body 34 includes a wheel 101 fitted and fixed to the drive axle 33, and a tire 102 fitted to the outer peripheral surface of the wheel 101.

[0049] In addition, the electric assist wheelchair cart 1 is provided with a battery (power source) (not shown). A power supply side harness 91 (see FIG. 1) is connected to the battery. The power supply side harness 91 extends between the battery and the drive bracket 31. A power supply side connector 92 (see FIG. 1) is connected to the end of the power supply side harness 91. A drive side motor connector 73 is connected to the power supply side connector 92. Thereby, the power of the battery is supplied to the coil 58 via the control board 59.

[0050] In addition, a control harness 93 (see FIG. 1) is connected to the control unit 9 (see FIG. 5) of the travel operation device 4. The control harness 93 extends from the control unit 9 to the drive bracket 31. A control connector 94 (see FIG. 1) is connected to the end of the control harness 93. A drive-side sensor connector 74 is connected to the control connector 94. As a result, information on the rotation angle of the rotor shaft 64 detected by the sensor 67 of the control board 59 is output to the control unit 9 as a signal.

[0051] <Travel operation device> FIG. 5 is an enlarged perspective view showing the travel operation device 4. FIG. 6 is a schematic plan view of the operation input device 13 for explaining the operation of the lever 15. The travel operation device 4 includes an operation input device 13 having a lever 15 (operating element), and a control unit 9 that controls the rotation direction and rotation speed difference of the left and right drive wheels 5, the on / off of the output, the increase and decrease of the output, etc. according to the operation of the lever 15. The lever 15 is tiltably supported by a holding portion (not shown) in the housing 14 of the operation input device 13. The lower end of the lever 15 is tiltable in any direction around the tilting center o. The lever 15 includes a shaft portion 15a whose lower end is supported by a holding portion in the housing 14, and a substantially disc-shaped operation flange portion 15b connected to the upper end portion of the shaft portion 15a. The lever 15 is biased by a spring member (not shown) so that the shaft portion 15a stands in a direction substantially orthogonal to the upper surface of the housing 14. The posture in which the shaft portion 15a of the lever 15 is substantially orthogonal to the upper surface of the housing 14 is defined as the initial posture. The lever 15 is biased by the above-described spring member so as to return to the initial posture. In the present embodiment, a joystick-type lever 15 is adopted as the operating element. In addition, the lower end of the shaft portion 15a of the lever 15 is held in the holding portion in the housing 14 so as to be pushable. The lower end of the shaft portion 15a of the lever 15 is biased toward the initial position by a return spring (not shown).

[0052] Inside the housing 14, there are provided a tilt detection sensor (not shown) for detecting the presence or absence of tilting of the lever 15 about the tilting center o and the tilting direction of the lever 15 (the tilting direction with respect to the central axis of the lever 15 in the initial posture), an output switching switch (not shown) for stepwise switching the output of the drive wheels 5 by the pushing operation of the lever 15, and the like. The detection signal detected by the tilt detection sensor and the switching signal of the output switching switch are input to the control unit 9. The control unit 9 controls the rotation direction, the rotation speed difference, the on / off of the output, etc. of the left and right drive wheels 5 according to the detection signal of the tilt detection sensor. Further, the control unit 9 stepwise switches the rotation output of the left and right drive wheels 5 in response to the switching signal of the output switching switch.

[0053] Next, with reference to FIG. 6, the tilting operation of the lever 15 and the control of the left and right drive wheels 5 by the operation will be described. Hereinafter, regarding the lever 15 (operating element), a Cartesian coordinate system as shown in FIG. 6 is defined. This Cartesian coordinate system is a Cartesian coordinate system having the tilting center o of the lever 15 as the origin and the X-axis (first coordinate axis) corresponding to the vehicle width direction and the Y-axis (second coordinate axis) corresponding to the vehicle longitudinal direction.

[0054] The control unit 9 determines the rotation direction of the left and right drive wheels 5 (electric motors 52) according to whether the tilting direction of the lever 15 is on the front side of the vehicle body or the rear side of the vehicle body with respect to the X-axis. Specifically, when the lever 15 is tilted forward with respect to the X-axis (the side corresponding to the front of the vehicle body), the rotation direction of the left and right drive wheels 5 is determined as the direction in which the vehicle body (electric assist basket cart 1) moves forward. Hereinafter, the rotation direction of the drive wheels 5 at this time is referred to as the "forward rotation direction". Conversely, when the lever 15 is tilted backward with respect to the X-axis (the side corresponding to the rear of the vehicle body), the rotation direction of the left and right drive wheels 5 is determined as the direction in which the vehicle body (electric assist basket cart 1) moves backward. Hereinafter, the rotation direction of the drive wheels 5 at this time is referred to as the "backward rotation direction".

[0055] The control unit 9 controls the left and right drive wheels 5 (electric motors 52) as follows according to the tilting direction of the lever 15 around the origin o. When the lever 15 is in the initial position (neutral position), the control unit 9 maintains the driving of the left and right drive wheels 5 (electric motors 52) in a stopped state.

[0056] <When moving forward> (a) When the lever 15 is tilted forward along the Y-axis (when the tilt angle with respect to the Y-axis is 0°), the control unit 9 outputs a command to rotate the left and right drive wheels 5 at a constant speed in the forward rotation direction to both drive wheels 5. When the electric motors 52 of the left and right drive wheels 5 are driven in response to this command, the vehicle body (electric assist cage cart 1) moves straight forward.

[0057] (b) When the lever 15 is tilted forward at a position shifted circumferentially within a range of a predetermined angle from the Y-axis around the origin o, the control unit 9 outputs a rotation command to the left and right drive wheels 5 such that the left and right drive wheels 5 rotate in the forward rotation direction, and the rotation speed of the drive wheel 5 located on the shifted side becomes relatively slower than the rotation speed of the drive wheel 5 located on the opposite side. The above-mentioned "predetermined angle" is set to 45° in the case of this embodiment. The "predetermined angle" during forward movement is an angle shifted 45° forward of the vehicle body with respect to the X-axis (first coordinate axis). For example, when the lever 15 is tilted at a position shifted clockwise within a range of a predetermined angle (45°) from the Y-axis around the origin o (a position tilted to the right), the control unit 9 outputs a rotation command to the left and right drive wheels 5 such that the rotation speed of the right drive wheel 5 becomes relatively slower than the rotation speed of the left drive wheel 5. When the electric motors 52 of both drive wheels 5 are driven in response to this command, the vehicle body (electric assist cage cart 1) moves forward while turning to the right. Conversely, when the lever 15 is tilted at a position shifted counterclockwise within a range of a predetermined angle (45°) from the Y-axis around the origin o (a position tilted to the left), the control unit 9 outputs a rotation command to both drive wheels 5 such that the rotation speed of the left drive wheel 5 becomes relatively slower than the rotation speed of the right drive wheel 5. When the electric motors 52 of the left and right drive wheels 5 are driven in response to this command, the vehicle body (electric assist cage cart 1) moves forward while turning to the left.

[0058] (c) When the lever 15 is tilted at a position shifted circumferentially beyond a predetermined angle (45°) from the Y-axis around the origin o, the command to rotate each drive wheel 5 is canceled. That is, when the lever 15 is tilted within this range, the assist by the drive wheels 5 for the vehicle body (electric assist cage cart 1) stops.

[0059] <When going backward> (d) When the lever 15 is tilted backward along the Y-axis (when the tilt angle with respect to the Y-axis is 0°), the control unit 9 outputs a command to rotate the left and right drive wheels 5 at a constant speed in the reverse rotation direction to the left and right drive wheels 5. When the electric motors 52 of the left and right drive wheels 5 are driven in response to this command, the vehicle body (electric assist cage cart 1) moves straight backward.

[0060] (e) When the lever 15 is tilted at a position shifted circumferentially within a range of a predetermined angle (45°) from the Y-axis around the origin o, the left and right drive wheels 5 rotate in the reverse rotation direction, and a rotation command is output to the left and right drive wheels 5 such that the rotation speed of the drive wheel 5 located on the shifted side becomes relatively slower than the rotation speed of the drive wheel 5 located on the opposite side. When the electric motors 52 of the left and right drive wheels 5 are driven in response to this command, the vehicle body (electric assist cage cart 1) moves backward so as to turn in the direction in which the lever 15 is tilted. The "predetermined angle" during backward movement is an angle shifted 45° to the rear side of the vehicle body with respect to the X-axis (the first coordinate axis).

[0061] (f) When the lever 15 is tilted at a position shifted circumferentially beyond a predetermined angle (45°) from the Y-axis around the origin o, the command to rotate each drive wheel 5 is canceled. As a result, the assist by the drive wheels 5 for the vehicle body (electric assist cage cart 1) stops.

[0062] In the case of this embodiment, when the lever 15 is tilted in the circumferential direction within a range of a predetermined angle (45°) from the Y-axis around the origin o, the rotational speed of the drive wheel 5 positioned on the shifted side is decelerated according to the degree corresponding to the circumferential shift angle. That is, the rotation of the left and right drive wheels 5 is controlled so that the rotational speed of the drive wheel 5 positioned on the shifted side becomes relatively slower than the rotational speed of the drive wheel 5 positioned on the opposite side according to the degree corresponding to the circumferential shift angle.

[0063] <Control by the control unit> FIGS. 7 and 8 are flowcharts showing an example of control by the control unit 9. Hereinafter, an example of specific control by the control unit 9 will be described with reference to FIGS. 7 and 8. Note that, in the flowcharts shown in FIGS. 7 and 8, the control for stepwise switching the output of the drive wheel 5 (electric motor 52) by pushing the lever 15 is omitted.

[0064] In step S101 shown in FIG. 7, it is determined whether the lever 15 is in a forward operation, that is, whether the lever 15 is tilted forward of the X-axis. If it is a forward operation, the process proceeds to step S102, and if it is not a forward operation, the process proceeds to step S202 shown in FIG. 8.

[0065] In step S102, it is determined whether the lever 15 is operated to go straight forward along the Y-axis. If it is a straight-ahead operation, the process proceeds to step S103, and if it is not a straight-ahead operation, the process proceeds to step S104. When the process proceeds to step S103, a command to rotate the left and right drive wheels 5 at a constant speed in the forward rotation direction is output to the electric motors 52 of the left and right drive wheels 5. Thereby, the vehicle body goes straight forward to the front side.

[0066] In step S104, it is determined whether the tilting direction of the lever 15 is right front (clockwise direction). If the tilting direction is the right front side, the process proceeds to step S105, and if the tilting direction is not the right front side, the process proceeds to step S106.

[0067] In step S105, it is determined whether the right tilt angle θ of the lever 15 from the Y-axis is within a predetermined angle range (0° < θ ≤ 45°). If the right tilt angle θ is within the predetermined angle range (0° < θ ≤ 45°), the process proceeds to step S107. If the right tilt angle θ exceeds the predetermined angle range (0° < θ ≤ 45°), the process proceeds to step S108.

[0068] In step S107, a command to rotate the left and right drive wheels 5 in the forward rotation direction and to make the rotation speed of the right drive wheel 5 slower than the rotation speed of the left drive wheel 5 is output to the electric motors 52 of the left and right drive wheels 5. At this time, the deceleration rate of the rotation speed of the right drive wheel 5 is in accordance with the deviation angle of the lever 15 from the Y-axis.

[0069] In step S108, the output command for the left and right drive wheels 5 is canceled. As a result, the assist force by the electric motor 52 does not act on the left and right drive wheels 5.

[0070] Also, when the tilt direction of the lever 15 is on the left tilt side with respect to the Y-axis and the process proceeds to step S106, in step S106, it is determined whether the left tilt angle θ of the lever 15 from the Y-axis is within a predetermined angle range (0° < θ ≤ 45°). If the left tilt angle θ is within the predetermined angle range (0° < θ ≤ 45°), the process proceeds to step S109. If the left tilt angle θ exceeds the predetermined angle range (0° < θ ≤ 45°), the process proceeds to step S108.

[0071] In step S109, a command to rotate the left and right drive wheels 5 in the forward rotation direction and to make the rotation speed of the left drive wheel 5 slower than the rotation speed of the right drive wheel 5 is output to the electric motors 52 of the left and right drive wheels 5. At this time, the deceleration rate of the rotation speed of the left drive wheel 5 is in accordance with the deviation angle of the lever 15 from the Y-axis. In step S108, the output command for the left and right drive wheels 5 is canceled as described above. As a result, the assist force by the electric motor 52 does not act on the left and right drive wheels 5.

[0072] Also, when the operation of the lever 15 is not a forward-side operation and the process proceeds to step S202 shown in FIG. 8, in step S202, it is determined whether the lever 15 has been linearly advanced rearward along the Y-axis. If it is a linear forward operation, the process proceeds to step S203; if it is not a linear forward operation, the process proceeds to step S204. When the process proceeds to step S203, a command to rotate the left and right drive wheels 5 at a constant speed in the reverse rotation direction is output to the electric motors 52 of the left and right drive wheels 5. Thereby, the vehicle body moves straight rearward.

[0073] In step S204, it is determined whether the tilting direction of the lever 15 is right rearward. In step S205, it is determined whether the right tilting angle θ of the lever 15 from the Y-axis is within a predetermined angle range (0° < θ ≤ 45°). If the right tilting angle θ of the lever 15 from the Y-axis is within the predetermined angle range, the process proceeds to step S207, and a command to rotate the left and right drive wheels 5 in the reverse rotation direction and make the rotation speed of the right drive wheel 5 slower than the rotation speed of the left drive wheel 5 is output to the electric motors 52 of the left and right drive wheels 5. If the right tilting angle θ of the lever 15 from the Y-axis exceeds the predetermined angle range (0° < θ ≤ 45°), the process proceeds to step S208, and the output command for the left and right drive wheels 5 is cancelled.

[0074] In step S206, it is determined whether the left tilting angle θ of the lever 15 from the Y-axis is within a predetermined angle range (0° < θ ≤ 45°). If the left tilting angle θ of the lever 15 from the Y-axis is within the predetermined angle range, the process proceeds to step S209, and a command to rotate the left and right drive wheels 5 in the reverse rotation direction and make the rotation speed of the left drive wheel 5 slower than the rotation speed of the right drive wheel 5 is output to the electric motors 52 of the left and right drive wheels 5. If the left tilting angle θ of the lever 15 from the Y-axis exceeds the predetermined angle range (0° < θ ≤ 45°), the process proceeds to step S208, and the output command for the left and right drive wheels 5 is cancelled.

[0075] <Effect of the Embodiment> As described above, in the traveling operation device 4 of the present embodiment, the control unit 9 controls the rotation direction, the rotation speed difference, and the on / off state of the left and right drive wheels 5 according to the tilting direction of the lever 15 (operating element) of the operation input device 13. Basically, when the lever 15 is operated forward, the control unit 9 rotates the left and right drive wheels 5 in the forward rotation direction, and when the lever 15 is operated backward, the control unit 9 rotates the left and right drive wheels 5 in the reverse rotation direction. When the lever 15 is operated along the Y-axis, the control unit 9 drives the left and right drive wheels 5 at a constant speed. When the lever 15 is tilted at a position circumferentially shifted within a predetermined angle range from the Y-axis around the origin o, the control unit 9 drives the drive wheel 5 on the shifted side at a relatively slower rotation speed than the drive wheel 5 on the opposite side. When the lever 15 is tilted at a position circumferentially shifted beyond a predetermined angle range from the Y-axis around the origin o, the control unit 9 cancels the driving of the left and right drive wheels 5. Therefore, in the traveling operation device 4 of the present embodiment, by tilting the lever 15 of the operation input device 13, it is possible to easily operate the straight-ahead movement and left and right turning assistance of the vehicle body (electric assist basket cart 1) and the stop of the assistance. Therefore, when the traveling operation device 4 of the present embodiment is adopted, the operability by the operator can be made better.

[0076] Further, in the traveling operation device 4 of the present embodiment, when the lever 15 is tilted at a position circumferentially shifted within a predetermined angle range from the Y-axis around the origin o, the control unit 9 controls the rotation speed difference between the left and right drive wheels 5 according to the degree corresponding to the circumferential shift angle. That is, the control unit 9 controls the rotation of each drive wheel 5 so that the rotation speed of the drive wheel 5 located on the shifted side of the lever 15 becomes relatively slower than the rotation speed of the drive wheel 5 located on the opposite side according to the degree corresponding to the circumferential shift angle. Therefore, in the traveling operation device 4 of the present embodiment, the vehicle body can be turned in a desired direction according to the degree corresponding to the circumferential shift angle of the lever 15 from the Y-axis. Therefore, when the traveling operation device 4 of the present embodiment is adopted, by adjusting the circumferential shift angle of the lever 15 from the Y-axis in the tilting direction by the operator, it becomes possible to easily and quickly adjust the turning state of the vehicle body.

[0077] In addition, the electric assist cage cart 1 (electric assist vehicle) adopting the traveling operation device 4 of the present embodiment has a free wheel in which the driven wheels 6 are rotatable about an axis facing in a substantially vertical direction, and the separation distance between the drive wheels 5 and the driven wheels 6 is longer than the separation distance between the left and right drive wheels 5. In this case, when the rotational speed difference between the left and right drive wheels 5 becomes large, it becomes difficult for a stable turning force due to the rotational speed difference to act on the vehicle body due to the wheel spin of one of the drive wheels 5 or the like. However, in the case of the traveling operation device 4 of the present embodiment, the circumferential region of the lever 15 that can be used for turning the vehicle body is limited to a range of a predetermined angle from the Y axis. Therefore, when the traveling operation device 4 of the present embodiment is adopted, it becomes possible to always apply a stable turning force (assist force for turning) to the vehicle body.

[0078] Furthermore, in the electric assist cage cart 1 (electric assist vehicle) adopting the traveling operation device 4 of the present embodiment, the drive wheels 5 and the driven wheels 6 are respectively arranged one by one near the four corners on the outer side in the vehicle width direction in the front and rear of the vehicle body. For this reason, the four corners of the vehicle body are stably supported by the drive wheels 5 and the driven wheels 6. In addition, in the electric assist cage cart 1 (electric assist vehicle) of the present embodiment, since the two drive wheels 5 are arranged sufficiently separated in the vehicle width direction of the vehicle body, it is possible to apply an assist force for stable turning to the vehicle body.

[0079] Also, in the traveling operation device 4 of the present embodiment, the circumferential angle (critical angle) of the lever 15 that can be used for turning the vehicle body is set to an angle of 45° each in the front and rear with respect to the X axis. That is, when the lever 15 is operated on the front side of the vehicle body with respect to the X axis, the critical angle is an angle shifted 45° to the front side of the vehicle body with the origin o as the center with respect to the X axis, and when the lever 15 is operated on the rear side of the vehicle body with respect to the X axis, the critical angle is an angle shifted 45° to the rear side of the vehicle body with the origin o as the center with respect to the X axis. The angular positions shifted 45° to the front side and the rear side with respect to the X axis are angular positions that are easy for the operator operating the lever 15 to grasp as a feeling. Therefore, when the traveling operation device 4 of the present embodiment is adopted, the operator can operate the lever 15 for vehicle body turning within a range of a predetermined angle without discomfort.

[0080] Further, in the traveling operation device 4 of the present embodiment, the lever 15 can be pushed in, and when the lever 15 is pushed in, the control unit 9 stepwise switches the output of the drive wheels 5. Therefore, when the traveling operation device 4 of the present embodiment is adopted, by pushing in the lever 15, the operator can easily change the output of the drive wheels 5.

[0081] Furthermore, in the electric assist wheelchair cart 1 (electric assist vehicle) adopting the traveling operation device 4 of the present embodiment, a gripping portion 12 for manually pushing and pulling the vehicle body in the traveling direction is provided, and an operation input device 13 having a lever 15 is provided on the gripping portion 12. Therefore, in a state where the operator grips the gripping portion 12, the lever 15 can be easily operated by fingertips or the like. Accordingly, when manually pushing and pulling the vehicle body, the operator can easily obtain the assist force by the drive wheels 5 even with only one hand. Therefore, when this configuration is adopted, the operability of the electric assist wheelchair cart 1 (electric assist vehicle) becomes better. Note that the main usage form of the electric assist wheelchair cart 1 of the present embodiment is that the operator pulls the handle 3 from the front side to move the loading platform 2. When the operator pulls from the front side to move the loading platform 2 in this way, it is difficult for the operator to hold and operate the handle 3 with both hands. Since the traveling operation device 4 of the present embodiment can operate the assist of the left and right drive wheels 5 only by tilting the lever 15 of the operation input device 13 in an arbitrary direction, the operation can be easily and accurately performed even when the handle 3 is held with one hand.

[0082] In addition, the control method of the traveling operation device 4 of the present embodiment includes steps of determining the tilting direction of the lever 15 (steps S101, S102, S104, S105, S106, S202, S204, S205, S206), and controlling the rotation direction of the drive wheels 5, the rotational speed difference between the left and right drive wheels 5, and the on / off of the output of the drive wheels 5 according to the determination result of the steps (steps S103, S107, S108, S109, S203, S207, S208, S209). Therefore, by incorporating a program for executing these steps into the control unit 9, it is possible to easily obtain the assist force of the drive wheels 5 according to the operator's intention.

[0083] When the configuration of the present embodiment is adopted, a user-friendly traveling operation device 4 can be provided. Therefore, when the configuration of the present embodiment is adopted, it is possible to contribute to Goal 11 of the Sustainable Development Goals (SDGs) led by the United Nations, which is to make cities and human settlements inclusive, safe, resilient and sustainable.

[0084] Note that the present invention is not limited to the above-described embodiment, and various design changes are possible without departing from the gist thereof. For example, in the electric assist basket cart 1 of the above-described embodiment, the driven wheels 6 and the drive wheels 5 are arranged at the four corners of the front, rear, left, and right of the vehicle body, but the arrangement of the driven wheels 6 and the drive wheels 5 is not limited to the four corners of the vehicle body. Further, the number of installed driven wheels 6 is not limited to two, and may be one or three or more. Furthermore, the number of installed drive wheels 5 (electric wheels) is not limited to two. The drive wheels 5 may be arranged at least one each on one side and the other side in the vehicle width direction, and the total number of installed wheels may be three or more.

[0085] In addition, in the above-described embodiment, the electric assist basket cart 1 is adopted as the electric assist vehicle, but the electric assist vehicle is not limited to this. The electric assist vehicle may have a shape and functions different from those of the above-described embodiment as long as it includes at least two drive wheels and at least one driven wheel.

[0086] In the above-described embodiment, a lever 15 having an operation flange portion 15b in a substantially disc shape on the head is adopted as an operator of the operation input device 13. However, the shape of the operator is not limited to this. The shape of the operator is not particularly limited as long as it can be tilted in an arbitrary direction around the circumference.

[0087] Furthermore, in the above-described embodiment, the critical angular position (predetermined angle) in the circumferential direction of the lever 15 from the Y-axis at which the output to the drive wheels 5 is canceled is set to 45°. However, this critical angular position (predetermined angle) is not necessarily limited to 45°, and can be set to any angular position between 0° and 90°.

[0088] Also, in the above-described embodiment, when the lever 15 is tilted at a position shifted circumferentially within a predetermined angle range from the Y-axis around the origin o, the rotational speed difference between the left and right drive wheels 5 is changed according to the degree corresponding to the shift angle of the lever 15. However, the rotational speed difference between the left and right drive wheels 5 does not necessarily have to be configured to change according to the degree corresponding to the shift angle of the lever 15.

[0089] Furthermore, in the above-described embodiment, the lever 15 can be pushed in, and the output of the drive wheels 5 can be changed stepwise by pushing in the lever 15. However, this configuration is not necessarily required, and the output of the drive wheels 5 may be constant.

[0090] Also, in the above-described embodiment, the drive unit of the drive wheels 5 is constituted by a motor 32 with a speed reducer. However, the drive unit of the drive wheels 5 is not necessarily limited to the motor 32 with a speed reducer. For example, it is also possible to use an electric motor 52 alone instead of the motor 32 with a speed reducer.

Explanation of Reference Numerals

[0091] 1... Electrically assisted wheelchair (electrically assisted vehicle), 2... Loading platform (vehicle body), 3... Handle, 4... Travel operation device, 5... Driving wheels (electric wheels), 6... Driven wheels, 7... Frame body, 8... Wheelchair body, 8a... Opening, 8b... Short side surface, 8c... Long side surface, 11... Support column, 12... Gripping part, 13... Operation input device, 14... Housing, 15... Lever (operator), 21... Driven bracket, 22... Driven axle, 23... Driven wheel body, 24... Wheel, 25... Tire, 31... Driving bracket, 32... Motor with reducer, 33... Driving axle, 33a... First end, 33b... Second end, 33c... Outer flange part, 34... Driving wheel body, 35... Support column, 36... Bracket body, 37... Top plate, 38... First side plate, 38a... Through hole, 38b... Outer surface, 39... Second side plate, 39a... Inner surface, 41... Bearing unit, 42... Bearing housing, 43... Bearing, 49... Bolt, 50... Mounting stay, 51... Case, 51a... Opening, 52... Electric motor, 53... Reducing mechanism part, 54... Cover, 55... Stator, 56... Rotor, 57... Stator core, 58... Coil, 59... Control board, 61... First bearing, 62... Second bearing, 63... Third bearing, 64... Rotor shaft, 65... Rotor core, 66... Permanent magnet, 67... Sensor, 71... Motor harness, 72... Sensor harness, 73... Driving side motor connector, 74... Driving side sensor connector, 81... Fourth bearing, 82... Rotational output part, 82a... Female screw part, 83... Gear, 84... Bolt insertion hole, 85... Bolt, 91... Power supply side harness, 92... Power supply side connector, 93... Control side harness, 94... Control side connector, 101... Wheel, 102... Tire, A1... Axis of rotation, A3... Axle center, R... Road surface, o... Tipping center (origin)

Claims

1. A vehicle body, Electric wheels arranged at least one each on one side and the other side in the vehicle width direction of the vehicle body, A traveling operation device for an electric assist vehicle, comprising at least one driven wheel arranged on the vehicle body at a distance from the electric wheel in the longitudinal direction of the vehicle body, An operation input device having an operator that can be tilted in any direction around a tilt center, A control unit that controls the rotation direction and the rotation speed difference between the electric wheel on one side in the vehicle width direction and the electric wheel on the other side in the vehicle width direction according to the tilt direction of the operator, Regarding the operator, when a rectangular coordinate system having a first coordinate axis corresponding to the vehicle width direction and a second coordinate axis corresponding to the longitudinal direction of the vehicle body is defined with the tilt center as the origin, The control unit, Determines the rotation direction of each electric wheel according to whether the tilt direction of the operator is on the front side or the rear side of the vehicle body with respect to the first coordinate axis, When the operator is tilted along the second coordinate axis, a command to rotate the electric wheel on one side and the electric wheel on the other side at the same speed is output to each electric wheel, When the operator is tilted at a position circumferentially displaced within a range of a predetermined angle from the second coordinate axis around the origin, a rotation command is output to each electric wheel such that the rotation speed of the electric wheel located on the displaced side becomes relatively slower than the rotation speed of the electric wheel located on the opposite side, When the operator is tilted at a position circumferentially displaced beyond the predetermined angle from the second coordinate axis around the origin, a command to rotate each electric wheel is canceled. A traveling operation device for an electric assist vehicle, characterized in that.

2. The control unit controls the rotation of each electric wheel such that when the operator is tilted at a position circumferentially displaced within a range of a predetermined angle from the second coordinate axis around the origin, the rotation speed of the electric wheel located on the displaced side becomes relatively slower than the rotation speed of the electric wheel located on the opposite side, according to the degree corresponding to the circumferential displacement angle. The traveling operation device for an electric assist vehicle according to Claim 1, characterized in that.

3. The driven wheel is a free wheel rotatably supported around an axis facing substantially the vertical direction, The separation distance between the electric wheel and the driven wheel is longer than the separation distance between the electric wheel on one side in the vehicle width direction and the electric wheel on the other side in the vehicle width direction. The traveling operation device for an electric assist vehicle according to Claim 2, characterized in that.

4. The driving operation device for an electric assist vehicle according to claim 3, wherein the electric wheels and the driven wheels are respectively arranged one by one near the four corners on the front and rear sides and the outer sides in the vehicle width direction of the vehicle body.

5. The predetermined angle is When the operator is operated forward of the vehicle body with reference to the first coordinate axis, it is an angle shifted 45° forward of the vehicle body around the origin with respect to the first coordinate axis. The driving operation device for an electric assist vehicle according to claim 4, wherein when the operator is operated rearward of the vehicle body with reference to the first coordinate axis, it is an angle shifted 45° rearward of the vehicle body around the origin with respect to the first coordinate axis.

6. The operator is capable of being pushed in, The control unit is characterized in that when the operator is pushed in, the output of the electric wheels is switched step by step. The driving operation device for an electric assist vehicle according to claim 1.

7. A gripping portion for manually pushing and pulling the vehicle body in the traveling direction is provided on the vehicle body, The driving operation device for an electric assist vehicle according to claim 1, wherein the operation input device is provided on the gripping portion.

8. A control method for a driving operation device of an electric assist vehicle according to claim 1, comprising: a step of determining the tilting direction of the operator; a step of controlling the rotation direction of the electric wheels, the rotational speed difference between the electric wheels on one side and the electric wheels on the other side, and the on / off of the output of the electric wheels according to the determination result of the step; A control method for a driving operation device of an electric assist vehicle, characterized by comprising the above steps.

Images