Driving wheel and electric auxiliary vehicle

Abstract

The invention provides a small-sized driving wheel with excellent durability and an electric auxiliary vehicle. The driving wheel includes: a driving bracket; a motor with a speed reducer, which is fixed to the drive bracket and generates a rotational force; the bearing is arranged on the driving bracket; a drive axle having a first end rotatably supported by the drive bracket via a bearing; and a drive wheel body that is provided to the drive axle and rotates integrally with the drive axle. The motor with a speed reducer comprises: a housing fixed to a drive bracket; and a rotation output unit rotatably supported by the housing via a fourth bearing. A second end portion of the drive axle is integrated with the rotation output portion, and the second end portion is rotatably supported by the housing via the rotation output portion and a fourth bearing.

Description

Technical Field

[0001] The invention relates to a driving wheel and an electric auxiliary vehicle. Background Art

[0002] Conventionally, there is known an electric assisted vehicle having a driving wheel (drive wheel) disposed at the bottom of a cart (for example, see Patent Document 1). The driving wheel assists when the cart is moved by manpower, thereby reducing the burden of moving the cart.

[0003] For example, the driving wheel described in Patent Document 1 includes: a torque transmission mechanism portion fixed to a bracket extending from the lower part of the cart; and an electric motor and a wheel mounted on the torque transmission mechanism portion. The torque transmission mechanism portion includes: a housing fixed to the bracket; and a drive shaft protruding from the housing. The torque transmission mechanism portion outputs the rotation of the electric motor through the drive shaft. The wheel is mounted on the drive shaft. That is, the drive shaft also serves as the axle of the wheel.

[0004] [Prior art literature]

[0005] [Patent Document]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 2020-121611 Summary of the invention

[0007] [Problems to be solved by the invention]

[0008] Furthermore, if the electric-assisted vehicle is to be used for various purposes, it is also conceivable to use the electric-assisted vehicle on a difficult road outdoors. However, in the above-mentioned prior art, the drive shaft as the axle is in a shape that is supported on one side of the housing, so the durability is low. Therefore, if the electric-assisted vehicle is used on a difficult road, there is a possibility that a malfunction will occur in the electric-assisted vehicle.

[0009] If the rigidity of the torque transmission mechanism is increased in order to improve durability, there is a problem that the usability of the electric assist vehicle is deteriorated, such as the size and weight of the device being increased.

[0010] Therefore, the present invention provides a drive wheel and an electric assist vehicle which are compact and have excellent durability.

[0011] [Technical means to solve the problem]

[0012] In order to solve the above-mentioned problems, in the first aspect of the present invention, the drive wheel includes: a bracket; a drive unit fixed to the bracket that generates a rotational force; a first bearing provided on the bracket; an axle, one end of which is rotatably supported on the bracket via the first bearing; and a wheel body provided on the axle and rotating integrally with the axle. The drive unit includes: a case fixed to the bracket; and a rotation output unit rotatably supported on the case via a second bearing. The second end of the axle, which is opposite to the first end, is integrated with the rotation output unit, and the second end is rotatably supported on the case via the rotation output unit and the second bearing.

[0013] With such a configuration, the second bearing provided in the drive unit can be utilized to bilaterally support the axle in cooperation with the first bearing provided on the bracket. Therefore, a small-sized drive wheel with excellent durability can be provided.

[0014] In the second aspect of the present invention, in the drive wheel of the first aspect, the drive unit is a motor with a speed reducer. The motor with a speed reducer includes: an electric motor housed in the case; and a speed reduction mechanism unit housed in the case that reduces the rotation of the electric motor. The speed reduction mechanism unit includes the rotation output unit.

[0015] In this way, by utilizing the speed reduction mechanism unit, even if the electric motor is miniaturized, a high output can be obtained. In addition, the bearing in the speed reduction mechanism unit can be used as the second bearing, so the entire drive unit can be miniaturized.

[0016] In the third aspect of the present invention, an electric assist vehicle includes: the drive wheel of the first aspect or the second aspect; and a vehicle body provided with the drive wheel. The drive wheels are respectively provided at least one on each side in the vehicle width direction at the lower part of the vehicle body, and the drive unit is arranged on the inner side in the vehicle width direction of the wheel body.

[0017] With such a configuration, there is no need to provide, for example, an axle for transmitting power between the drive wheels arranged on both sides in the vehicle width direction. Therefore, sufficient space for foreign objects to pass through can be ensured at the lower part of the vehicle body. In addition, since the drive wheel has excellent durability, an electric assist vehicle with good usability even on rough roads can be provided.

[0018] In addition, since the drive unit is arranged on the inner side in the vehicle width direction of the wheel body, a small-sized electric assist vehicle that can suppress the size in the vehicle width direction as much as possible can be provided.

[0019] In the fourth aspect of the present invention, in the electric assist vehicle of the third aspect, in the vehicle body, at least the two drive wheels arranged on both sides in the vehicle width direction can be folded.

[0020] No axle or the like is provided between the drive wheels arranged on both sides in the vehicle width direction. Therefore, the vehicle body can be folded between the two drive wheels arranged on both sides in the vehicle width direction.

[0021] Therefore, the layout space of the electric assist vehicle when not in use can be saved as much as possible.

[0022] In the fifth aspect of the present invention, in the electric assist vehicle of the third or fourth aspect, the drive wheels are detachably provided on the vehicle body, and the drive wheels include: a drive-side connector detachably provided on a power-source-side connector mounted on a power-source-side wire harness extending from the power source of the vehicle body; and a drive-side wire harness electrically connecting the drive-side connector to the drive unit, and the drive-side connector is fixed to the bracket.

[0023] With such a configuration, even when a power source is provided on the vehicle body side, the drive wheels can be easily mounted or detached from the vehicle body. By detaching the drive wheels, the vehicle body can also be stably arranged on the ground. Thus, a user-friendly electric assist vehicle can be provided.

[0024] [Effects of the Invention]

[0025] According to the present invention, the drive wheels and the electric assist vehicle can be miniaturized, and the durability can be improved. [Description of the Drawings]

[0026] Figure 1 is a perspective view of an electric assist basket trolley in an embodiment of the present invention.

[0027] Figure 2 is a perspective view of the right drive wheel in an embodiment of the present invention as viewed obliquely from the front.

[0028] Figure 3 is along Figure 2 a sectional view taken along the rotation axis of the drive wheel shown.

[0029] [Description of Reference Numerals]

[0030] 1: Electric assist basket trolley (electric assist vehicle)

[0031] 2: Cargo box (vehicle body)

[0032] 3: Handle

[0033] 4: Operation unit

[0034] 5: Drive wheel

[0035] 6: Driven wheel

[0036] 7: Frame (vehicle body)

[0037] 8: Basket main body (vehicle body)

[0038] 8a: Opening part

[0039] 8b: Short side

[0040] 8c: Long side

[0041] 11: Support column

[0042] 12: Holding part

[0043] 13: Operation part main body

[0044] 14: Housing

[0045] 15: Rod

[0046] 21: Driven bracket

[0047] 22: Driven axle

[0048] 23: Driven wheel main body

[0049] 24: Wheel

[0050] 25: Tire

[0051] 31: Driving bracket (bracket)

[0052] 32: Motor with speed reducer (driving part)

[0053] 33: Driving axle (axle)

[0054] 33a: First end

[0055] 33b: Second end

[0056] 33c: Outer flange part

[0057] 34: Driving wheel main body (wheel main body)

[0058] 35: Support column

[0059] 36: Bracket main body

[0060] 37: Top plate

[0061] 38: First side plate

[0062] 38a: Through hole

[0063] 38b: Outer surface

[0064] 39: Second side plate

[0065] 39a: Inner surface

[0066] 41: Bearing unit

[0067] 42: Bearing housing

[0068] 43: Bearing (first bearing)

[0069] 50: Mounting brace

[0070] 51: Housing

[0071] 51a: Opening

[0072] 52: Electric motor

[0073] 53: Reduction gear mechanism section

[0074] 54: Cover

[0075] 55: Stator

[0076] 56: Rotor

[0077] 57: Stator core

[0078] 58: Coil

[0079] 59: Control board

[0080] 61: First bearing

[0081] 62: Second bearing

[0082] 63: Third bearing

[0083] 64: Rotor shaft

[0084] 65: Rotor core

[0085] 66: Permanent magnet

[0086] 67: Sensor

[0087] 71: Motor harness

[0088] 72: Sensor harness

[0089] 73: Drive-side motor connector

[0090] 74: Drive-side sensor connector

[0091] 81: Fourth bearing (second bearing)

[0092] 82: Rotational output section

[0093] 82a: Internal thread section

[0094] 83: Gear

[0095] 84: Bolt insertion through-hole

[0096] 85: Bolt

[0097] 91: Power-side wire harness

[0098] 92: Power-side connector

[0099] 93: Control-side wire harness

[0100] 94: Control-side connector

[0101] 101: Wheel

[0102] 102: Tire

[0103] A1: Axis of rotation

[0104] A2: Axle center

[0105] A3: Axle center

[0106] R: Road surface Detailed implementation manners

[0107] Next, the implementation manners of the present invention will be described based on the accompanying drawings.

[0108] <Electrically assisted basket trolley>

[0109] Figure 1 is a perspective view of an electrically assisted basket trolley 1 as an electrically assisted vehicle. In the following description, it is assumed that the electrically assisted basket trolley 1 is placed on a road surface R, and the up-down direction and the horizontal direction are described.

[0110] As Figure 1 shown, the electrically assisted basket trolley 1 includes: a cargo box 2; a handle 3 provided on the cargo box 2; an operation unit 4 provided on the handle 3; and drive wheels 5 and driven wheels 6 provided at the lower part of the cargo box 2.

[0111] The cargo box 2 includes a rectangular parallelepiped-shaped frame 7 that is rectangular in one direction when viewed from the up-down direction, and a basket main body 8 housed in the frame 7. The basket main body 8 is formed of a deformable raw material such as a net, for example. In addition, the basket main body 8 is formed in a rectangular parallelepiped shape corresponding to the frame 7 and has an opening 8a at the upper part.

[0112] The frame 7 can be folded to bring the short sides 8b on both sides in the long side direction of the side surface of the basket main body 8 closer to and separated from each other. In addition, the frame 7 can be folded to bring the long sides 8c on both sides in the short side direction of the side surface of the basket main body 8 closer to and separated from each other.

[0113] The handle 3 includes: a support column 11 that extends upward from the frame 7 on one of the two short sides 8b; and an annular grip portion 12 provided at the upper end of the support column 11. The user holds the grip portion 12 and pulls the electric-assisted basket cart 1 to move forward. That is, the electric-assisted basket cart 1 takes the side of the short side 8b where the handle 3 is provided as the front in the traveling direction. The traveling direction is the same as the long side direction of the basket main body 8.

[0114] In the following description, the long side direction of the cargo box 2 is referred to as the front-rear direction, and the short side direction of the cargo box 2 orthogonal to the front-rear direction is referred to as the vehicle width direction. Sometimes, the right side and the left side when observing the front in the vehicle width direction are simply referred to as the right side and the left side. In Figure 1 the posture of the drive wheels 5 and the driven wheels 6 is the posture when the electric-assisted basket cart 1 travels straight forward or backward. When explaining the drive wheels 5 and the driven wheels 6, the explanation is based on the posture when the electric-assisted basket cart 1 travels straight forward or backward.

[0115] The operation unit 4 performs drive control of the drive wheels 5. The operation unit 4 includes an operation unit main body 13 and a control device (not shown) that performs drive control of the drive wheels 5 based on the operation of the operation unit main body 13.

[0116] The operation unit main body 13 is, for example, a so-called joystick. The operation unit main body 13 includes a housing 14 fixed to the grip portion 12 and a lever 15 that is tiltably supported by the housing 14. Information on the tilting direction of the lever 15 is output as a signal to the control device. The control device performs drive control of the drive wheels 5 based on the signal output from the lever 15.

[0117] Two drive wheels 5 and two driven wheels 6 are respectively provided. The drive wheels 5 and the driven wheels 6 are respectively provided at the four corner portions in the lower part of the frame 7. More specifically, the drive wheels 5 are respectively provided on both sides in the vehicle width direction at the rear in the lower part of the frame 7. The driven wheels 6 are respectively provided on both sides in the vehicle width direction at the front in the lower part of the frame 7. In this way, the distance between the drive wheels 5 and the driven wheels 6 arranged in the front-rear direction is longer than the distance between the two drive wheels 5 and the distance between the two driven wheels 6 arranged in the vehicle width direction.

[0118] The driven wheel 6 includes: a driven bracket 21 that is rotatably and detachably provided on the frame 7; a driven axle 22 that is rotatably supported by the driven bracket 21; and a driven wheel body 23 that is fixed to the driven axle 22. The structure of the driven bracket 21 is the same as that of the drive bracket 31 described later, so the description here is omitted. The driven wheel body 23 includes: a wheel 24 that is fitted and fixed to the driven axle 22; and a tire 25 that is fitted on the outer peripheral surface of the wheel 24.

[0119] <Drive Wheels>

[0120] The two drive wheels 5 have the same structure and are symmetrically arranged with the center in the vehicle width direction as the center. Therefore, in the following description, only the drive wheel 5 arranged on the right side among the two drive wheels 5 will be described, and the description of the drive wheel 5 arranged on the left side will be omitted.

[0121] Figure 2 It is a perspective view of the drive wheel 5 on the right side observed from the obliquely front. Figure 3 It is along Figure 2 The sectional view of the drive wheel 5 along the rotation axis A1 shown.

[0122] As Figures 1 to 3 shown, the drive wheel 5 includes: a drive bracket 31, which is rotatably and detachably provided on the frame 7; a motor 32 with a speed reducer, which is fixed on the drive bracket 31; a drive axle 33, which is supported by the motor 32 with a speed reducer and the drive bracket 31; and a drive wheel body 34, which is installed on the drive axle 33.

[0123] <Drive Bracket>

[0124] The drive bracket 31 includes: a support column 35, which can be inserted and removed in the vertical direction relative to the frame 7; and a bracket body 36, which is integrally formed with the lower end of the support column 35. The support column 35 is formed long in the vertical direction. The support column 35 is rotatable around the axis A2 relative to the frame 7.

[0125] The bracket body 36 is formed by stamping and bending a strip-shaped metal plate and is formed in a U shape with an opening downward. That is, the bracket body 36 includes a top plate 37 and two side plates 38, 39 (the first side plate 38, the second side plate 39) that bend and extend downward from both sides in the vehicle width direction of the top plate 37.

[0126] On the outer side in the vehicle width direction ( Figure 2 , Figure 3 is the left side in this case) of the two side plates 38, 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. The first end portion 33a on the outer side in the vehicle width direction of the drive axle 33 is inserted through the through hole 38a.

[0127] At the lower end of the first side plate 38, a bearing unit 41 is provided on the outer surface 38b on the outer side in the vehicle width direction (left side). The bearing unit 41 includes: a bearing housing 42, which is fixed on the outer surface 38b of the first side plate 38; and a bearing (an example of the first bearing in the technical solution) 43, which is 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 the bearing 43.

[0128] <Motor with Speed Reducer>

[0129] The motor 32 with a speed reducer is fixed to the inner side in the vehicle width direction ( Figure 2 , Figure 3 the right side in the following) of the second side plate 39 among the two side plates 38 and 39 via the mounting brace 50 and using bolts 49. The motor 32 with a speed reducer includes: a housing 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 that are coaxially arranged and housed in the housing 51 with respect to the rotation axis A1. 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.

[0130] The housing 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 housing 51. A cover 54 is attached to the housing 51 to close the opening 51a.

[0131] 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 housing 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 more than the stator 55 and the rotor 56. The electric motor 52 is covered with the cover 54 from above the control board 59.

[0132] The stator 55 includes a stator core 57 formed in an annular shape and a coil 58 wound around the stator core 57. The outer peripheral surface of the stator core 57 is fitted to the inner peripheral surface of the housing 51, so that the stator core 57 is fixed to the housing 51. The coil 58 is connected to the control board 59.

[0133] The rotor 56 includes: a rotor shaft 64 that is rotatably supported by the housing 51 or 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 that is 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.

[0134] For example, a plurality of switching elements (not shown) or a sensor 67 for detecting the rotation angle of the rotor shaft 64 are mounted on the control board 59. The sensor 67 outputs the information on the rotation angle of the rotor shaft 64 detected as a signal. In addition, a motor wiring harness 71 and a sensor wiring harness 72 are connected to the control board 59.

[0135] The motor wiring harness 71 is electrically connected to the coil 58. The sensor wiring harness 72 is electrically connected to the sensor 67. These wiring harnesses 71, 72 are led out to the outside via the housing 51. A drive-side motor connector 73 is connected to the end of the led-out motor wiring harness 71. A drive-side sensor connector 74 is connected to the end of the led-out sensor wiring harness 72. These connectors 73, 74 are fixed to the drive bracket 31.

[0136] The reduction mechanism unit 53 is housed on the vehicle-width direction outer side of the housing 51 relative to the electric motor 52. The reduction mechanism unit 53 uses, for example, a so-called cycloid reduction mechanism. The reduction mechanism unit 53 includes: a rotation output unit 82 that is rotatably supported by the housing 51 via a fourth bearing (an example of the second bearing in the technical solution) 81; and a plurality of gears 83 that reduce the rotation of the rotor shaft 64 and transmit it to the rotation output unit 82. Thus, the rotation of the rotor shaft 64 is output in a reduced speed via the rotation output unit 82.

[0137] The second end portion 33b of the drive axle 33 opposite to the first end portion 33a is fixed to the rotation output unit 82. More specifically, an outer flange portion 33c that protrudes radially outward is integrally formed at the second end portion 33b of the drive axle 33. A plurality of bolt insertion holes 84 that penetrate axially 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 internal thread portions 82a that communicate with the bolt insertion holes 84 are formed in the rotation output unit 82.

[0138] Bolts 85 are respectively inserted into the bolt insertion holes 84 from above the outer flange portion 33c, and these bolts 85 are tightened into the internal thread portions 82a. Thus, the second end portion 33b of the drive axle 33 is fixed to the rotation output unit 82, and the drive axle 33 and the rotation output unit 82 are integrated.

[0139] That is, 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 housing 51 via the rotation output unit 82 and the fourth bearing 81.

[0140] <Drive wheel main body>

[0141] The drive wheel main body 34 is disposed between the motor 32 with a speed reducer and the first side plate 38 of the drive bracket 31 in the drive axle 33. The drive wheel main body 34 includes: a wheel 101 that is fitted and fixed to the drive axle 33; and a tire 102 that is fitted to the outer peripheral surface of the wheel 101.

[0142] In addition, a battery (power source) (not shown) is provided in the electric-assist basket handcart 1. A power-source side wire harness 91 is connected to the battery. The power-source side wire harness 91 extends between the battery and the drive bracket 31. A power-source side connector 92 is connected to the end of the power-source side wire harness 91. The drive-side motor connector 73 is connected to the power-source side connector 92. Thus, the electric power of the battery is supplied to the coil 58 via the control substrate 59.

[0143] In addition, a control-side wire harness 93 is connected to a control device (not shown). The control-side wire harness 93 extends between the control device (not shown) and the drive bracket 31. A control-side connector 94 is connected to the end of the control-side wire harness 93. The drive-side sensor connector 74 is connected to the control-side connector 94. Thus, the information on the rotation angle of the rotor shaft 64 detected by the sensor 67 of the control substrate 59 is output as a signal to the control device.

[0144] <Operation of the electric-assist basket handcart>

[0145] Next, the operation of the electric-assist basket handcart 1 will be described.

[0146] When the user holds the grip portion 12 of the handle 3 and pulls the cargo box 2 forward, the rod 15 of the operation portion 4 is tilted forward. Then, a control device (not shown) drives the drive wheels 5 based on the operation of the rod 15. At this time, the electric power of a battery (not shown) is supplied to the respective coils 58 of the left and right drive wheels 5 via the control substrate 59. In each electric motor 52 of the drive wheels 5, the electric power is selectively supplied to a desired coil 58 based on the rotation angle of the rotor shaft 64 detected by the sensor 67.

[0147] When electric power is supplied to the coil 58, a prescribed linked magnetic flux is formed in the stator 55. A magnetic attractive force or repulsive force is generated between the linked magnetic flux and the permanent magnet 66 of the rotor 56. Thus, the rotor 56 rotates, and further, the rotation output portion 82 and the drive axle 33 rotate via the speed reduction mechanism portion 53. In addition, the drive wheel body 34 rotates integrally with the drive axle 33. Thus, when the user wants to move the cargo box 2, it is assisted by the drive wheels 5.

[0148] Here, when going straight ahead, the rod 15 is maintained in a state of tilting forward. In this case, the left and right drive wheels 5 continue to rotate at the same speed. In contrast, for example, when changing the traveling path of the electric-assisted basket cart 1 to the obliquely forward direction, the rod 15 is tilted toward the desired traveling path. Then, a control device (not shown) creates a speed difference between the left and right drive wheels 5. For example, when changing the traveling path of the electric-assisted basket cart 1 to the right direction, the rotational speed of the right drive wheel 5 is made slower than that of the left drive wheel 5. Thereby, the traveling path of the electric-assisted basket cart 1 is changed to the right direction.

[0149] The same applies when the electric-assisted basket cart 1 is made to reverse. In this case, the user pushes the cargo box 2 and reverses. At this time, the rod 15 is tilted backward. When changing the traveling path of the electric-assisted basket cart 1 to the obliquely backward direction, it is the same as the case of changing the traveling path to the obliquely forward direction.

[0150] In addition, for example, when the rod 15 is tilted in the left-right direction, the left and right drive wheels 5 are stopped.

[0151] When the electric-assisted basket cart 1 is running, the first end portion 33a of the drive axle 33 is rotatably supported by the drive bracket 31 via the bearing 43. The second end portion 33b of the drive axle 33 is rotatably supported by the housing 51 via the rotation output portion 82 and the fourth bearing 81. That is, the drive axle 33 is bilaterally supported by the drive bracket 31 and the motor 32 with a speed reducer. Therefore, compared with the case of unilaterally supporting the drive axle 33, the rigidity of the drive wheels 5 can be improved.

[0152] Therefore, with the drive wheels 5, sufficient durability can be obtained even when the electric-assisted basket cart 1 runs on a rough road.

[0153] In order to bilaterally support the drive axle 33, the fourth bearing 81 of the motor 32 with a speed reducer is used. Therefore, it is not necessary to provide two bearings in the drive bracket 31, for example, to bilaterally support the drive axle 33. Therefore, the durability of the drive wheels 5 can be improved while achieving miniaturization.

[0154] As the drive unit of the drive wheels 5, a motor 32 with a speed reducer including a speed reduction mechanism portion 53 is used. By using the speed reduction mechanism portion 53, high output can be obtained even if the electric motor 52 is miniaturized. In addition, the drive axle 33 can be bilaterally supported by the fourth bearing 81 in the speed reduction mechanism portion 53. Therefore, even when using the motor 32 with a speed reducer, the entire drive wheels 5 can be miniaturized.

[0155] A motor 32 with a speed reducer is provided on each of the two drive wheels 5 respectively. Therefore, there is no need to provide an axle for power transmission between the left and right drive wheels 5, for example. As a result, sufficient space for foreign objects to pass through can be ensured under the cargo box 2. In addition, the drive wheels 5 have excellent durability, so an electric-assisted basket cart 1 with good usability even on rough roads can be provided.

[0156] On each of the two drive wheels 5, a motor 32 with a speed reducer is arranged on the inner side in the vehicle width direction. Therefore, a small-sized electric-assisted basket cart 1 with dimensions in the vehicle width direction suppressed as much as possible can be provided.

[0157] The frame 7 of the cargo box 2 can be folded to bring the short sides 8b on both sides in the long side direction closer to and separated from each other. In addition, the frame 7 can be folded to bring the long sides 8c on both sides in the short side direction closer to and separated from each other. That is, there is no need to provide an axle for power transmission between the left and right drive wheels 5, for example, so the frame 7 between the left and right drive wheels 5 can be folded. Therefore, when the electric-assisted basket cart 1 is not in use, the installation space of the electric-assisted basket cart 1 can be saved as much as possible.

[0158] The connectors 73 of each wire harness 71 led out from the motor 32 with a speed reducer and the connectors 74 of the wire harness 72 are fixed to the drive bracket 31. Therefore, for example, when the drive wheel 5 is detached from the cargo box 2, the power supply side connector 92 is detached from the drive side motor connector 73. In addition, the control side connector 94 is detached from the drive side sensor connector 74. Just by such operations, the drive wheel 5 can be easily detached from the cargo box 2. In this way, although a battery or a control device (not shown) needs to be electrically connected to the drive wheel 5, the drive wheel 5 and the cargo box 2 can be easily loaded and unloaded. By detaching the drive wheel 5, the cargo box 2 can also be stably arranged on the road surface R. Thus, a user-friendly electric-assisted basket cart 1 can be provided.

[0159] While improving the durability of the drive wheels 5, miniaturization can be achieved, so it can contribute to Goal 7 "Ensure access for all to affordable, reliable and sustainable modern energy", Goal 9 "Build resilient infrastructure, promote inclusive and sustainable industrialization and foster innovation", and Goal 12 "Ensure sustainable consumption and production patterns" of the United Nations-led Sustainable Development Goals (SDGs).

[0160] A user-friendly electric-assisted basket cart 1 can be provided, so it can contribute to Goal 11 "Make cities and human settlements inclusive, safe, resilient and sustainable" of the United Nations-led Sustainable Development Goals (SDGs).

[0161] The present invention is not limited to the described embodiments, and includes embodiments in which various changes are made to the described embodiments within the scope not departing from the gist of the present invention.

[0162] For example, in the described embodiment, it is described that the drive wheels 5 or the operation unit 4 are provided in the electric assist basket trolley 1 which is an electric assist vehicle. However, it is not limited thereto, and the drive wheels 5 or the operation unit 4 can be applied to various cargo boxes, trolleys, racks, trucks, etc. that need to be transported. The shape of the cargo box 2 is not limited to a rectangular parallelepiped shape and can be various shapes.

[0163] In the described embodiment, it is described that by setting a speed difference between the left and right drive wheels 5, the electric assist basket trolley 1 is changed to a desired traveling path. However, it is not limited thereto, and the traveling path of the electric assist basket trolley 1 can also be changed by rotating the left and right drive wheels 5 in opposite directions respectively.

[0164] In the described embodiment, it is described that the frame 7 can be folded so that the short side surfaces 8b on both sides in the long side direction approach and separate from each other, and the frame 7 can be folded so that the long side surfaces 8c on both sides in the short side direction approach and separate from each other. However, it is not limited thereto, and in the frame 7, it is sufficient that it can be folded at least between the two drive wheels 5 arranged on both sides in the vehicle width direction.

[0165] In the described embodiment, it is described that a motor 32 with a speed reducer is provided as the drive unit of the drive wheel 5. However, it is not limited thereto, and any structure that becomes the drive source of the drive wheel main body 34 is acceptable. For example, an electric motor 52 can be used alone instead of the motor 32 with a speed reducer. As long as the drive axle 33 can be bilaterally supported by the bearing provided in the drive unit and the bearing 43 provided in the drive bracket 31 in cooperation.

[0166] In the described embodiment, it is described that the drive bracket 31 is formed in a U-shaped bracket main body 36 with an opening at the lower side. It is described that the bearing unit 41 having the bearing 43 is provided on the outer surface 38b of the first side plate 38 of the bracket main body 36. However, it is not limited thereto, and the shape of the drive bracket 31 and the arrangement position of the bearing 43 (bearing unit 41) can be arbitrarily changed.

Claims

1. A drive wheel, characterized in that, Comprising: Bracket; Drive part, fixed to the bracket, generating a rotational force; First bearing, arranged on the bracket; Axle, the first end of which is rotatably supported on the bracket via the first bearing; And Wheel body, arranged on the axle, rotating integrally with the axle, The drive part includes: Housing, fixed to the bracket; And Rotational output part, rotatably supported on the housing via a second bearing, The second end of the axle, which is opposite to the first end, is integrated with the rotational output part, The second end is rotatably supported on the housing via the rotational output part and the second bearing.

2. The drive wheel according to claim 1, wherein The drive part is a motor with a speed reducer, The motor with a speed reducer includes: Electric motor, housed in the housing; and Speed reduction mechanism part, housed in the housing, reducing the rotation of the electric motor, The speed reduction mechanism part includes the rotational output part.

3. An electric assisted vehicle, characterized in that, Comprising: The drive wheel according to claim 1 or 2; And Vehicle body, provided with the drive wheel, The drive wheels are respectively arranged at least one on each side in the vehicle width direction at the lower part of the vehicle body, The drive part is arranged inside the vehicle width direction of the wheel body.

4. The electric assisted vehicle according to claim 3, wherein In the vehicle body, at least between the two drive wheels arranged on both sides in the vehicle width direction can be folded.

5. The electric assisted vehicle according to claim 3, wherein The drive wheel is detachably arranged on the vehicle body, The drive wheel includes: Drive side connector, detachably arranged on the power supply side connector installed on the power supply side wire harness extending from the power supply of the vehicle body; and Drive side wire harness, electrically connecting the drive side connector and the drive part, The drive side connector is fixed to the bracket.

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