Drive wheels and bogies

Abstract

To lower a floor.SOLUTION: A driving wheel 103 includes: a first input member 36A which is rotatably provided and has an annular shape; a second input member 36B which is arranged shifting in an axis O1 direction coaxially with the first input member and provided so as to be rotatable independently of the first input member and has an annular shape; a first output shaft 40A and a second output shaft 40B respectively disposed on axes different from each other; a first spur gear 39A which engages with an inner periphery of the first input member to transmit rotational force of the first input member to the first output shaft; a second spur gear 39B which engages with an inner periphery of the second input member to transmit rotational force of the second input member to the second output shaft; a wheel 16 fixed to an axle 37; a first bevel gear mechanism 15A which transmits rotational force of the first output shaft to one end of the axle; a second bevel gear mechanism 15B which transmits rotational force of the second output shaft to the other end of the axle; and a pivot shaft 34 which pivotally supports the wheel through the axle.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a drive wheel and a bogie. [Background technology]

[0002] Patent Document 1 discloses a driving wheel and a bogie using the driving wheel. The driving wheel includes a first input shaft and a second input shaft arranged on the same axis, a first output shaft and a second output shaft arranged on a different axis, a first spur gear mechanism for transmitting the rotational force of the first input shaft to the first output shaft, a second spur gear mechanism for transmitting the rotational force of the second input shaft to the second output shaft, wheels connected to an axle, a turning shaft for supporting the wheels rotatably via the axle, a first power conversion mechanism for transmitting the rotational force of the first output shaft to one end of the axle, and a second power conversion mechanism for transmitting the rotational force of the second output shaft to the other end of the axle. In addition, as a preferable embodiment, the driving wheel is arranged such that the rotational axis of the wheel along the vertical direction intersecting the axial direction of the axle is offset in a horizontal direction perpendicular to the axial direction of the axle with respect to the axis of the turning shaft. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-024033 A Summary of the Invention [Problem to be solved by the invention]

[0004] The drive wheels described in Patent Document 1 allow the two mounted drive devices to operate simultaneously, whether changing the direction of the wheels or rotating the wheels, while simplifying the structure and ensuring sufficient ground clearance. Furthermore, by making the drive wheels in an offset manner, the wheels can passively turn by an external force acting from the horizontal direction when they are not driven.

[0005] Here, the drive wheel described in Patent Document 1 has a first input shaft and a second input shaft coaxially arranged at the center of rotation of the wheel to enable the two mounted drive devices to operate simultaneously, and an input section (two-shaft integrated motor) is arranged on the upper side of a base plate through which each input shaft penetrates. When the drive wheel is attached to a cart or the like, it is necessary to avoid the input section. For this reason, there is a problem that it is difficult to attach the drive wheel at the same height as the swivel caster that serves as the driven wheel on the cart.

[0006] The present disclosure has been made in consideration of the above-mentioned problems, and aims to provide a drive wheel and bogie that can achieve a low floor. [Means for solving the problem]

[0007] In order to achieve the above-mentioned object, a drive wheel of one embodiment of the present disclosure includes a rotatably arranged first input member having a circular ring shape, a second input member having a circular ring shape arranged coaxially but shifted in the axial direction from the first input member and arranged to be rotatable independently of the first input member, a first output shaft and a second output shaft arranged on separate axes, a first transmission mechanism that engages with an inner periphery of the first input member to transmit a rotational force of the first input member to the first output shaft, a second transmission mechanism that engages with an inner periphery of the second input member to transmit the rotational force of the second input member to the second output shaft, a wheel fixed to an axle, a first power conversion mechanism that transmits the rotational force of the first output shaft to one end of the axle, a second power conversion mechanism that transmits the rotational force of the second output shaft to the other end of the axle, and a turning shaft that rotatably supports the wheel via the axle.

[0008] As a desirable aspect of the above-mentioned drive wheel, it comprises a first input portion that engages with an outer periphery of the annular shape of the first input member to input a rotational force to the first input member, and a second input portion that engages with an outer periphery of the annular shape of the second input member to input a rotational force to the second input member.

[0009] In a preferred embodiment of the drive wheel, the first output shaft and the second output shaft are disposed on both sides of the wheel in the axial direction of the axle.

[0010] In a preferred embodiment of the drive wheel, the first power conversion mechanism and the second power conversion mechanism are disposed on both sides of the wheel in the axial direction of the axle.

[0011] As a desirable embodiment of the above-mentioned drive wheel, the first power conversion mechanism transmits the rotational force of the first output shaft to one end of the axle which has a different axial direction from the first output shaft, and any one of a bevel gear mechanism, a helical gear mechanism, a worm gear mechanism, a crown gear mechanism, or a universal joint mechanism is applied, and the second power conversion mechanism transmits the rotational force of the second output shaft to one end of the axle which has a different axial direction from the second output shaft, and any one of a bevel gear mechanism, a helical gear mechanism, a worm gear mechanism, a crown gear mechanism, or a universal joint mechanism is applied.

[0012] In a preferred embodiment of the drive wheel, the pivot shaft is arranged such that its axis is shifted in a horizontal direction perpendicular to the axis of the axle relative to the rotation axis of the wheel, which is aligned in a vertical direction and intersects the axis of the axle.

[0013] In order to achieve the above object, a bogie according to one aspect of the present disclosure comprises the above drive wheel and a bogie body to which the drive wheel is attached. Effect of the Invention

[0014] According to the present disclosure, a low floor can be achieved. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is a perspective view showing an example of the configuration of a drive wheel. [Diagram 2] FIG. 2 is a plan view showing the drive wheels. [Diagram 3] FIG. 3 is a bottom view showing the drive wheels. [Figure 4] FIG. 4 is a cross-sectional view taken along line AA in FIG. [Diagram 5] FIG. 5 is a cross-sectional view taken along line BB of FIG. [Figure 6] FIG. 6 is a schematic diagram showing a driving force transmission path of a driving wheel. [Figure 7] FIG. 7 is a perspective view showing another example of the configuration of the drive wheel. [Figure 8] FIG. 8 is a plan view showing another example of the configuration of the drive wheels. [Figure 9] FIG. 9 is a bottom view showing another configuration example of the drive wheel. [Figure 10] FIG. 10 is a cross-sectional view taken along line CC of FIG. [Figure 11] FIG. 11 is a perspective view illustrating a configuration example of the power conversion mechanism. [Figure 12] FIG. 12 is a perspective view illustrating a configuration example of the power conversion mechanism. [Figure 13] FIG. 13 is a front view showing an example of the configuration of the power conversion mechanism. [Figure 14] FIG. 14 is a schematic diagram illustrating an example of the configuration of the cart. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, the embodiments for carrying out the invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the following embodiments. Furthermore, the components in the following embodiments include those that a person skilled in the art can easily imagine, those that are substantially the same, and those that are within the so-called equivalent range. Furthermore, the components disclosed in the following embodiments can be appropriately combined.

[0017] [Embodiment 1] FIG. 14 is a schematic diagram showing an example of the configuration of the carriage.

[0018] As shown in FIG. 14, the cart 100 includes a cart body 101, a handle portion 102, four drive wheels 103, a power supply portion 104, a control device 105, and an operation portion 106.

[0019] The dolly body 101 is, for example, a flat plate material, and has a rectangular shape in a plan view. A handle portion 102 is fixed to one side of the dolly body 101 in the longitudinal direction. Four drive wheels 103 are attached to the four corners of the rear surface of the dolly body 101. The four drive wheels 103 are rotatable and steerable. A power supply portion 104 and a control device 105 are attached to the rear surface of the dolly body 101 between the front and rear drive wheels 103, and an operation portion 106 is attached to the handle portion 102. The control device 105 includes a computer system. The computer system includes a processor such as a CPU, and a memory such as a ROM or RAM.

[0020] Therefore, the control device 105, which receives an operation signal from the operation unit 106, controls the drive wheels 103 of the dolly 100. This allows the dolly 100 to run and turn automatically. Note that the operation unit 106 does not have to be provided on the dolly 100 (handle unit 102) and may be configured as a remote control device separated from the dolly 100, allowing the dolly 100 to be remotely operated by wire or wirelessly.

[0021] The cart body 101 has a flat surface, and thus an object to be transported can be placed on the flat surface. That is, the cart 100 can be configured as an automatic guided vehicle (AGV). The cart 100 can also be configured as a device that travels by placing equipment along the flat surface of the cart body 101. Examples of the equipment include various types of equipment, such as a hand lifter, a forklift, a picking robot, and medical equipment.

[0022] The number and arrangement of the drive wheels 103 of the dolly 100 and the device are not limited to the above-mentioned configuration. For example, in the above-mentioned four-wheel configuration, the dolly 100 and the device may have a pair of drive wheels 103 attached to the front side of the dolly 100 and driven wheels (driven wheels that do not rotate on a single axle) attached to the rear side of the dolly 100. In addition, although not shown in the figure, in a configuration with three or more wheels, the dolly 100 and the device may have one drive wheel 103 and all the other wheels may be driven wheels. In addition, although not shown in the figure, in a configuration with three or more wheels, the dolly 100 and the device may have no driven wheels and all the wheels may be drive wheels 103. That is, in a configuration with three or more wheels, the dolly 100 and the device may have at least one drive wheel 103.

[0023] The drive wheel 103 will be described in detail below. Fig. 1 is a perspective view showing an example of the configuration of the drive wheel. Fig. 2 is a plan view showing the drive wheel. Fig. 3 is a bottom view showing the drive wheel. Fig. 4 is a cross-sectional view taken along line AA in Fig. 2. Fig. 5 is a cross-sectional view taken along line BB in Fig. 2.

[0024] The drive wheel 103 has an input portion 11 , a turning portion 12 , an input member 13 , a transmission mechanism 14 , a power conversion mechanism 15 , and a wheel 16 .

[0025] The input unit 11 is disposed below the plate-shaped main body 10 with its plate surfaces facing up and down. The main body 10 is fixed to the cart main body 101 of the cart 100. The input unit 11 is fixed to the main body 10 by a support member (not shown). The swivel unit 12 is disposed below the main body 10 as a separate body from the input unit 11. The input member 13 receives the rotational force of the input unit 11. The transmission mechanism 14 transmits the rotational force input to the input member 13. The power conversion mechanism 15 transmits the rotational force of the transmission mechanism 14 to the wheels 16. The wheels 16 are freely rotatable by the rotational force input via the input unit 11, the input member 13, the transmission mechanism 14, and the power conversion mechanism 15, and are steerable by the swivel unit 12.

[0026] The input unit 11, the rotating unit 12, the input member 13, the transmission mechanism 14, the power conversion mechanism 15, and the wheels 16 will be described in detail below.

[0027] The input unit 11 has a first input unit 30A and a second input unit 30B. The first input unit 30A is configured with a motor. The first input unit 30A is fixed to the main body 10. The first input unit 30A has a first input gear 32A provided on a first input shaft 30Aa. In the embodiment, the first input gear 32A is configured with a spur gear. The first input gear 32A inputs a rotational force to the input member 13 (first input member 36A) by rotating via the first input shaft 30Aa when the first input unit 30A is driven. On the other hand, when the first input unit 30A is not driven, the first input shaft 30Aa is rotatable and the first input gear 32A is rotatable.

[0028] The second input portion 30B is configured with a motor. The second input portion 30B is fixed to the main body 10. The second input portion 30B has a second input gear 32B provided on a second input shaft 30Ba. In the embodiment, the second input gear 32B is configured with a spur gear. The second input gear 32B inputs a rotational force to the input member 13 (second input member 36B) by rotating via the second input shaft 30Ba when the second input portion 30B is driven. On the other hand, when the second input portion 30B is not driven, the second input shaft 30Ba is rotatable and the second input gear 32B is rotatable.

[0029] The swivel unit 12 is formed in a disk shape and is supported by a bearing 33 on the main body 10 so as to be rotatable about an axis O1 located at the center of the disk shape. Therefore, the swivel unit 12 constitutes a swivel shaft 34. In other words, the swivel shaft 34 extends along the axis O1 direction along which the axis O1 extends, and is supported so as to be rotatable about the axis O1. The axis O1, which is the center of the swivel shaft 34, is provided parallel to the axis of the first input shaft 30Aa of the first input unit 30A and the second input shaft 30Ba of the second input unit 30B. The swivel unit 12 supports the input member 13, the transmission mechanism 14, the power conversion mechanism 15, and the wheels 16. The swivel unit 12 also has a casing 35 that houses the transmission mechanism 14, the power conversion mechanism 15, and the wheels 16. The casing 35 is disposed below the main body 10. The swivel unit 12, together with the input member 13, the transmission mechanism 14, the power conversion mechanism 15, and the wheels 16, is supported so as to be rotatable about an axis O1 of the swivel shaft .

[0030] The input member 13 has a first input member 36A and a second input member 36B. The first input member 36A is formed in an annular shape and is rotatably arranged coaxially along the axis O1. The first input member 36A has external teeth 36Aa formed along the outer periphery of the annular shape. The first input member 36A has the external teeth 36Aa meshed with and engaged with the first input gear 32A in the input section 11. Therefore, the first input member 36A receives a rotational force from the first input gear 32A. The first input member 36A has internal teeth 36Ab formed along the inner periphery of the annular shape. The first input member 36A has the internal teeth 36Ab meshed with and engaged with the first support gear 38A. The first support gear 38A is rotatably supported by a support shaft 38C, whose axis is parallel to the axis O1, via a bearing 38Aa, as shown in FIG. 4. The support shaft 38C is fixed to the swivel section 12. The first support gears 38A may be provided at a plurality of locations on the annular shape of the first input member 36A. Therefore, the first input member 36A is rotatably disposed coaxially along the axis O1 with respect to the turning part 12 via the first support gear 38A, and a rotational force is input from the first input gear 32A by driving the first input part 30A.

[0031] The second input member 36B is formed in an annular shape having the same diameter as the first input member 36A, is disposed coaxially along the axis O1 with a shift in the direction of the axis O1, and is disposed rotatably independent of the first input member 36A. The second input member 36B is formed in the same size and shape as the first input member 36A. The second input member 36B has external teeth 36Ba formed along the outer periphery of the annular shape. The external teeth 36Ba have the same diameter, tooth shape, number of teeth, and pitch as the external teeth 36Aa of the first input member 36A. The second input member 36B has the external teeth 36Ba meshed with the second input gear 32B in the input portion 11 and engaged therewith. Therefore, the second input member 36B receives a rotational force from the second input gear 32B. The second input member 36B also has internal teeth 36Bb formed along the inner periphery of the annular shape. The internal teeth 36Bb have the same diameter, tooth shape, number of teeth, and pitch as the internal teeth 36Ab of the first input member 36A. The internal teeth 36Bb of the second input member 36B mesh with and engage with the second support gear 38B. As shown in FIG. 4, the second support gear 38B is rotatably supported via a bearing 38Ba on a support shaft 38C whose axis is parallel to the axis O1. The second support gear 38B is arranged coaxially with the first support gear 38A on the support shaft 38C, and is formed to have the same size and shape as the first support gear 38A. The second support gear 38B may be provided at a plurality of locations on the annular shape of the second input member 36B. Therefore, the second input member 36B is rotatably arranged coaxially along the axis O1 with respect to the turning portion 12 via the second support gear 38B, and a rotational force is input from the second input gear 32B by driving the second input portion 30B.

[0032] The transmission mechanism 14 has a first spur gear 39A as a first transmission mechanism and a second spur gear 39B as a second transmission mechanism. The first spur gear 39A meshes with the internal teeth 36Ab of the first input member 36A in the input member 13. The first spur gear 39A is fixed to a first output shaft 40A. As shown in FIG. 5, the first output shaft 40A is provided extending in the vertical direction. The upper end of the first output shaft 40A is rotatably supported by a bearing 40Aa on the disk-shaped part of the revolving part 12, and the lower end is rotatably supported by a bearing 40Ab on the casing 35 of the revolving part 12. Therefore, the first spur gear 39A is supported rotatably around an axis O3 parallel to the axis O1 via the first output shaft 40A.

[0033] The second spur gear 39B meshes with the internal teeth 36Bb of the second input member 36B of the input member 13. The second spur gear 39B has the same diameter, tooth profile, number of teeth, and pitch as the first spur gear 39A. The second spur gear 39B is fixed to the second output shaft 40B. As shown in FIG. 5, the second output shaft 40B is provided to extend in the vertical direction. The upper end of the second output shaft 40B is rotatably supported by a bearing 40Ba relative to the disk-shaped portion of the revolving unit 12, and the lower end is rotatably supported by a bearing 40Bb relative to the casing 35 of the revolving unit 12. Therefore, the second spur gear 39B is supported rotatably around an axis O4 parallel to the axis O1 via the second output shaft 40B.

[0034] In the driving wheel 103 of the embodiment, the first input gear 32A meshes with the external teeth 36Aa of the first input member 36A, and the first support gear 38A and the first spur gear 39A mesh with the internal teeth 36Ab. Therefore, the first input member 36A is supported by the first input gear 32A, the first support gear 38A, and the first spur gear 39A at three different points in the circumferential direction so as to be rotatable in the circumferential direction. Therefore, in the driving wheel 103 of the embodiment, the first support gear 38A can be disposed at only one point for the first input member 36A. In addition, in the driving wheel 103 of the embodiment, the second input gear 32B meshes with the external teeth 36Ba of the second input member 36B, and the second support gear 38B and the second spur gear 39B mesh with the internal teeth 36Bb. Therefore, the second input member 36B is supported at three different circumferential positions by the second input gear 32B, the second support gear 38B, and the second spur gear 39B so as to be rotatable in the circumferential direction. Therefore, in the driving wheel 103 of the embodiment, the second support gear 38B can be disposed at only one position relative to the second input member 36B.

[0035] The power conversion mechanism 15 is a bevel gear mechanism that transmits the rotational force of the transmission mechanism 14 to the wheels 16. The power conversion mechanism 15 has a first bevel gear mechanism 15A as a first power conversion mechanism and a second bevel gear mechanism 15B as a second power conversion mechanism. The first bevel gear mechanism 15A has a first driving bevel gear 41A and a first driven bevel gear 42A. The first driving bevel gear 41A is fixed to a first output shaft 40A in the transmission mechanism 14. Therefore, the first driving bevel gear 41A is supported rotatably around the axis O3 together with the first spur gear 39A, which is the first transmission mechanism. The first driven bevel gear 42A is fixed to an axle 37. The axle 37 extends in the direction of the axis O2 perpendicular to the axis O1 direction and the axis O3 direction, and both ends are supported rotatably by bearings 37a with respect to the casing 35 of the swivel unit 12. The wheels 16 are fixed to the center of the axle 37. The first driven bevel gear 42A is fixed to one end of the axle 37 and supported so as to be rotatable about the axis O2 together with the wheel 16. The first driving bevel gear 41A and the first driven bevel gear 42A mesh with each other.

[0036] The second bevel gear mechanism 15B has a second driving bevel gear 41B and a second driven bevel gear 42B. The second driving bevel gear 41B has the same diameter, tooth profile, number of teeth, and pitch as the first driving bevel gear 41A. The second driving bevel gear 41B is fixed to the second output shaft 40B of the transmission mechanism 14. Therefore, the second driving bevel gear 41B is supported rotatably around the axis O4 together with the second spur gear 39B, which is the second transmission mechanism. The second driven bevel gear 42B is fixed to the other end side of the axle 37 and supported rotatably around the axis O2 together with the wheel 16. That is, the second driven bevel gear 42B is disposed so as to sandwich the wheel 16 between the axle 37 and the first driven bevel gear 42A. That is, the first output shaft 40A to which the first spur gear 39A and the first driving bevel gear 41A are fixed, and the second output shaft 40B to which the second spur gear 39B and the second driving bevel gear 41B are fixed are disposed on both sides of the wheel 16 in the direction of the axis O2 of the axle 37. The second driving bevel gear 41B and the second driven bevel gear 42B mesh with each other.

[0037] The wheel 16 is fixed to the axle 37 as described above. The wheel 16 is disposed such that the rotation axis O5 of the wheel 16, which is aligned vertically and intersects with the axis O2 of the axle 37, is shifted in a horizontal direction perpendicular to the axis O2 of the axle 37 relative to the axis O1 of the swivel shaft 34. In the driving wheel 103 of the embodiment, the first output shaft 40A to which the first spur gear 39A and the first driving bevel gear 41A are fixed, and the second output shaft 40B to which the second spur gear 39B and the second driving bevel gear 41B are fixed are disposed on the axis O2 in a plan view as shown in Figs. 2 and 3. In addition, in the driving wheel 103 of the embodiment, the rotation axis O5 of the wheel 16 is shifted in a horizontal direction perpendicular to the axis O2. For this reason, the driving wheel 103 of the embodiment is disposed such that the axis O1 of the swivel unit 12, the axis O3, and the axis O4 form an isosceles triangle in a plan view. 4 and 5, the wheel 16 is provided with its lower end protruding below the casing 35. Therefore, the lower end of the wheel 16, including the rotation axis O5, can contact the floor surface G (see FIG. 14). Although not shown in the figures, in the driving wheel 103 of the embodiment and a driving wheel 103' described later, the wheel 16 may be configured so that the rotation axis O5 coincides with the axis O1 of the revolving shaft 34.

[0038] The driving wheel 103 of the embodiment can rotate and steer the wheels 16 by rotating the first output shaft 40A and the second output shaft 40B by driving the first input unit 30A and the second input unit 30B, which are motors. That is, the driving wheel 103 rotates the first output shaft 40A via the first input gear 32A, the first input member 36A, and the first spur gear 39A by driving the first input unit 30A, thereby rotating the axle 37 via the first driving bevel gear 41A and the first driven bevel gear 42A. In addition, the driving wheel 103 rotates the second output shaft 40B via the second input gear 32B, the second input member 36B, and the second spur gear 39B by driving the second input unit 30B, thereby rotating the axle 37 via the second driving bevel gear 41B and the second driven bevel gear 42B. The driving wheels 103 rotate the first output shaft 40A and the second output shaft 40B in the same direction and set the number of rotations (rotation speed) of the first output shaft 40A and the second output shaft 40B to be the same, thereby rotating the wheels 16 and moving forward or backward. The driving wheels 103 rotate the first output shaft 40A and the second output shaft 40B in opposite directions and set the number of rotations (rotation speed) of the first output shaft 40A and the second output shaft 40B to be the same, thereby rotating the wheels 16 without steering. At this time, the driving wheels 103 can steer the wheels 16 while rotating or stopped by making the number of rotations (rotation speed) of the first output shaft 40A and the second output shaft 40B different. On the other hand, the driving wheels 103 can follow the rotation and steering of the wheels 16 by not driving the first input unit 30A and the second input unit 30B, which are motors.

[0039] Here, a description will be given of the operation of the drive wheel 103. Figure 6 is a schematic diagram showing a drive force transmission path of the drive wheel.

[0040] In the driving wheel 103, as shown in FIG. 6, when the first input member 36A rotates in the first direction A1, the first spur gear 39A rotates in the second direction A2, which is the same direction. When the first spur gear 39A rotates in the second direction A2, the first driving bevel gear 41A, which is integral with the first spur gear 39A via the first output shaft 40A, rotates in the same direction. Then, the first driven bevel gear 42A meshing with the first driving bevel gear 41A rotates in the third direction A3, causing the axle 37, which is integral with the first driven bevel gear 42A, to rotate in the same direction. On the other hand, in the driving wheel 103, when the second input member 36B rotates in the first direction B1, which is the opposite direction to the first direction A1, the second spur gear 39B rotates in the second direction B2, which is the same direction. When the second spur gear 39B rotates in the second direction B2, which is the same direction, the second driving bevel gear 41B, which is integral with the second spur gear 39B via the second output shaft 40B, rotates in the same direction. Then, the second driven bevel gear 42B meshing with the second driving bevel gear 41B rotates in the third direction B3, rotating the axle 37 integral with the second driven bevel gear 42B in the same direction. Here, since the third direction A3 and the third direction B3 are the same rotational direction, if the first input member 36A and the second input member 36B have the same rotation speed, the wheel 16 rotates without turning, and the driving wheel 103 moves forward or backward.

[0041] At this time, when the rotation speed of the second input member 36B is reduced relative to the rotation speed of the first input member 36A, the rotation speed input from the second driving bevel gear 41B to the axle 37 via the second driven bevel gear 42B becomes lower than the rotation speed input from the first driving bevel gear 41A to the axle 37 via the first driven bevel gear 42A. Then, the turning shaft 34 rotates by the rotation speed difference, and the wheels 16 turn and are steered. In addition, when the rotation of the second input member 36B is stopped, the rotation speed input from the second driving bevel gear 41B to the axle 37 via the second driven bevel gear 42B becomes zero, and the wheels 16 turn and are steered without rotating.

[0042] Although not shown in the figure, the driving wheel 103 has a swivel position detector. The swivel position detector is provided in the main body 10. The swivel position detector has, for example, a first spur gear that rotates around the axis O1 together with the swivel shaft 34, a second spur gear that meshes with the first spur gear and rotates around an axis parallel to the axis O1, and a detector that detects the rotation position of the second spur gear. Therefore, the driving wheel 103 can detect the rotation position of the swivel shaft 34, i.e., the rotation position of the swivel unit 12 relative to the main body 10, by rotating the first spur gear together with the swivel shaft 34 and detecting the rotation position of the first spur gear as the rotation position of the second spur gear with the detector. The detection signal of the detector is input to the control device 105 of the cart (equipment) 100. As a result, the control device 105 can control the rotation of the driving wheel 103.

[0043] In this manner, the driving wheel 103 of the embodiment includes a rotatably provided annular first input member 36A, an annular second input member 36B arranged coaxially with the first input member 36A but shifted in the direction of the axis O1 and arranged rotatably independent of the first input member 36A, a first output shaft 40A and a second output shaft 40B arranged on different axes, a first spur gear (first transmission mechanism) 39A that engages with the inner periphery of the first input member 36A to transmit the rotational force of the first input member 36A to the first output shaft 40A, The vehicle includes a second spur gear (second transmission mechanism) 39B that engages with the inner circumference of the second input member 36B and transmits the rotational force of the second input member 36B to the second output shaft 40B, a wheel 16 fixed to the axle 37, a first bevel gear mechanism (first power conversion mechanism) 15A that transmits the rotational force of the first output shaft 40A to one end of the axle 37, a second bevel gear mechanism (second power conversion mechanism) 15B that transmits the rotational force of the second output shaft 40B to the other end of the axle 37, and a rotating shaft 34 that rotatably supports the wheel 16 via the axle 37.

[0044] Therefore, in the driving wheel 103 of the embodiment, the rotational force of the first input member 36A and the second input member 36B is transmitted to the first output shaft 40A and the second output shaft 40B via the first spur gear 39A and the second spur gear 39B, and is transmitted from the first output shaft 40A and the second output shaft 40B to each end of the axle 37 via the first bevel gear mechanism 15A and the second bevel gear mechanism 15B. With this configuration, the driving wheel 103 can switch between the rotation and steering of the wheels 16 by adjusting the rotation speed of the first input member 36A and the second input member 36B. Therefore, since the driving wheel 103 has the bevel gear mechanisms 15A and 15B disposed at each end of the axle 37, respectively, the transmission system of the rotational force to the wheels 16 is simplified, and the structure can be simplified and a sufficient minimum ground clearance can be ensured.

[0045] Moreover, the driving wheel 103 of the embodiment includes annular first input member 36A and second input member 36B arranged coaxially and shifted in the direction of the axis O1 to be rotatable independently of each other, and the rotational force of the first input member 36A and the second input member 36B is transmitted to the first output shaft 40A and the second output shaft 40B via the first spur gear 39A and the second spur gear 39B. Therefore, the driving wheel 103 can input the rotational force from the annular outer periphery of the first input member 36A and the second input member 36B, so that the input portion 11 can be arranged to be deployed on the outside of the rotation. As a result, the driving wheel 103 can achieve a lower floor compared to when the input portion 11 is arranged along the axial direction of the rotation.

[0046] The driving wheel 103 of the embodiment includes a first input portion 30A that engages with the annular outer periphery of the first input member 36A to input a rotational force to the first input member 36A, and a second input portion 30B that engages with the annular outer periphery of the second input member 36B to input a rotational force to the second input member 36B. Therefore, the driving wheel 103 has the first input portion 30A and the second input portion 30B disposed outside the rotation of the first input member 36A and the second input member 36B, and can achieve a low floor.

[0047] In the driving wheel 103 of the embodiment, the first output shaft 40A and the second output shaft 40B are disposed on both sides of the wheels 16 in the direction of the axis O2 of the axle 37. Therefore, the driving wheel 103 receives rotational force from both sides in the direction of the axis O2 of the axle 37, which allows for a low floor and simplifies the differential mechanism for steering the wheels 16.

[0048] In the driving wheel 103 of the embodiment, the first bevel gear mechanism 15A and the second bevel gear mechanism 15B are disposed on both sides of the wheel 16 in the direction of the axis O2 of the axle 37. Therefore, the driving wheel 103 receives rotational force from both sides in the direction of the axis O2 of the axle 37, which allows for a low floor and simplifies the differential mechanism for steering the wheel 16.

[0049] In the driving wheel 103 of the embodiment, the rotation axis O5 of the wheel 16 along the vertical direction intersecting with the axis O2 of the axle 37 is arranged to be shifted in the horizontal direction perpendicular to the axis O2 of the axle 37 with respect to the axis O1 of the turning shaft 34. Therefore, when the driving wheel 103 is not driving the wheel 16, the wheel 16 can passively turn by an external force acting from the horizontal direction. That is, the driving wheel 103 can automatically run and steer the cart 100, and can also manually run and steer the cart 100 by an operator.

[0050] The bogie 100 of the embodiment includes a driving wheel 103 and a bogie body 101 to which the driving wheel 103 is attached. Therefore, the bogie 100 can achieve a low floor.

[0051] Fig. 7 is a perspective view showing another example of the configuration of the drive wheel. Fig. 8 is a plan view showing another example of the configuration of the drive wheel. Fig. 9 is a bottom view showing another example of the configuration of the drive wheel. Fig. 10 is a cross-sectional view taken along CC in Fig. 8.

[0052] A drive wheel 103' shown in Figures 7 to 10 is different from the drive wheel 103 shown in Figures 1 to 6 and described in detail, in that the power conversion mechanism 17 is different, but the other configurations are the same. Therefore, in the drive wheel 103', the same parts as those of the drive wheel 103 are given the same reference numerals and the description thereof will be omitted.

[0053] The power conversion mechanism 17 is a helical gear mechanism, and transmits the rotational force of the transmission mechanism 14 to the wheels 16. The power conversion mechanism 17 has a first helical gear mechanism 17A as a first power conversion mechanism and a second helical gear mechanism 17B as a second power conversion mechanism. The first helical gear mechanism 17A is composed of a first driving helical gear 51A fixed to a lower part of the first output shaft 40A, and a first driven helical gear 52A fixed to one end of the axle 37 provided on the wheels 16 in the direction of the axis O2 and meshing with the first driving helical gear 51A. The second helical gear mechanism 17B is composed of a second driving helical gear 51B fixed to a lower part of the second output shaft 40B, and a second driven helical gear 52B fixed to the other end of the axle 37 in the direction of the axis O2 and meshing with the second driving helical gear 51B.

[0054] In the driving wheel 103' of the embodiment, the rotational force of the first input member 36A and the second input member 36B is transmitted to the first output shaft 40A and the second output shaft 40B via the first spur gear 39A and the second spur gear 39B, and is transmitted from the first output shaft 40A and the second output shaft 40B to each end of the axle 37 via the first helical gear mechanism 17A and the second helical gear mechanism 17B. The driving wheel 103' can switch between the rotation and steering of the wheels 16 by adjusting the rotation speed of the first input member 36A and the second input member 36B. Therefore, since the driving wheel 103' has the helical gear mechanisms 17A and 17B disposed at each end of the axle 37, the transmission system of the rotational force to the wheels 16 is simplified, the structure can be simplified, and the floor can be made lower.

[0055] In this manner, the driving wheel 103 ′ can be configured by replacing the power conversion mechanism 17 with that of the driving wheel 103 .

[0056] Further, the configuration example in which the power conversion mechanism is changed for the drive wheels 103, 103' is not limited to this.

[0057] Fig. 11 is a perspective view showing an example of the configuration of the power conversion mechanism. Fig. 12 is a perspective view showing an example of the configuration of the power conversion mechanism. Fig. 13 is a front view showing an example of the configuration of the power conversion mechanism. Note that the configuration of the drive wheel equipped with the power conversion mechanisms 18, 19, and 20 shown in Figs. 11 to 13 is the same as the drive wheel 103 described above, and the same reference numerals are used for the equivalent parts and the description will be omitted.

[0058] The power conversion mechanism 18 shown in FIG. 11 is a worm gear mechanism, and transmits the rotational force of the transmission mechanism 14 to the wheels 16. The power conversion mechanism 18 has a first worm gear mechanism 18A as a first power conversion mechanism and a second worm gear mechanism 18B as a second power conversion mechanism. The first worm gear mechanism 18A is composed of a first worm 53A fixed to the lower part of the first output shaft 40A, and a first worm wheel 54A fixed to one end of the axle 37 provided on the wheels 16 in the direction of the axis O2 and meshing with the first worm 53A. The second worm gear mechanism 18B is composed of a second worm 53B fixed to the lower part of the second output shaft 40B, and a second worm wheel 54B fixed to the other end of the axle 37 in the direction of the axis O2 and meshing with the second worm 53B.

[0059] In the drive wheels equipped with this power conversion mechanism 18, the rotational force of the first input member 36A and the second input member 36B is transmitted to the first output shaft 40A and the second output shaft 40B via the first spur gear 39A and the second spur gear 39B, and is transmitted from the first output shaft 40A and the second output shaft 40B to each end of the axle 37 via the first worm gear mechanism 18A and the second worm gear mechanism 18B. The drive wheels can switch between the rotation and steering of the wheels 16 by adjusting the rotation speed of the first input member 36A and the second input member 36B. Therefore, since the drive wheels have the worm gear mechanisms 18A and 18B disposed at each end of the axle 37, respectively, the transmission system of the rotational force to the wheels 16 is simplified, the structure can be simplified, and this can contribute to a lower floor.

[0060] The first worm gear mechanism 18A may be configured such that the first worm wheel 54A is fixed to the lower part of the first output shaft 40A, and the first worm 53A is fixed to one end of the axle 37 in the direction of the axis O2. The second worm gear mechanism 18B may be configured such that the second worm wheel 54B is fixed to the lower part of the second output shaft 40B, and the second worm 53B is fixed to the other end of the axle 37 in the direction of the axis O2.

[0061] The power conversion mechanism 19 shown in FIG. 12 is a crown gear mechanism, which transmits the rotational force of the transmission mechanism 14 to the wheels 16. The power conversion mechanism 19 has a first crown gear mechanism 19A as a first power conversion mechanism and a second crown gear mechanism 19B as a second power conversion mechanism. The first crown gear mechanism 19A is composed of a first crown gear 55A fixed to the lower part of the first output shaft 40A, and a first spur gear 56A fixed to one end of the axle 37 provided on the wheels 16 in the direction of the axis O2 and meshing with the first crown gear 55A. The second crown gear mechanism 19B is composed of a second crown gear 55B fixed to the lower part of the second output shaft 40B, and a second spur gear 56B fixed to the other end of the axle 37 in the direction of the axis O2 and meshing with the second crown gear 55B.

[0062] In the drive wheels equipped with this power conversion mechanism 19, the rotational force of the first input member 36A and the second input member 36B is transmitted to the first output shaft 40A and the second output shaft 40B via the first spur gear 39A and the second spur gear 39B, and is then transmitted from the first output shaft 40A and the second output shaft 40B to each end of the axle 37 via the first crown gear mechanism 19A and the second crown gear mechanism 19B. The drive wheels can switch between the rotation and steering of the wheels 16 by adjusting the rotation speed of the first input member 36A and the second input member 36B. Therefore, since the drive wheels have the crown gear mechanisms 19A and 19B disposed at each end of the axle 37, respectively, the transmission system of the rotational force to the wheels 16 is simplified, the structure can be simplified, and this can contribute to a lower floor.

[0063] The first crown gear mechanism 19A may be configured such that a first spur gear 56A is fixed to the lower part of the first output shaft 40A, and a first crown gear 55A is fixed to one end of the axle 37 in the direction of the axis O2. The second crown gear mechanism 19B may be configured such that a second spur gear 56B is fixed to the lower part of the second output shaft 40B, and a second crown gear 55B is fixed to the other end of the axle 37 in the direction of the axis O2.

[0064] The power conversion mechanism 20 shown in Fig. 13 is a universal joint mechanism, which transmits the rotational force of the transmission mechanism 14 to the wheels 16. The power conversion mechanism 20 has a first universal joint mechanism 20A as a first power conversion mechanism and a second universal joint mechanism 20B as a second power conversion mechanism. The first universal joint mechanism 20A is composed of a first driving joint 57A fixed to a lower end of the first output shaft 40A, a first driven joint 58A fixed to one end in the axis center O2 direction of the axle 37 provided on the wheels 16, and a first connecting portion 59A connecting the first driving joint 57A and the first driven joint 58A. The second universal joint mechanism 20B is composed of a second drive joint 57B fixed to a lower end of the second output shaft 40B, a second driven joint 58B fixed to the other end of the axle 37 in the direction of the axis O2, and a second connecting portion 59B connecting the second drive joint 57B and the second driven joint 58B. Although not shown in the figures, the first universal joint mechanism 20A may have a configuration in which one end of the first connecting portion 59A is fixed to the lower end of the first output shaft 40A, the other end of the first connecting portion 59A is fixed to one end of the axle 37 in the direction of the axis O2, and a single or multiple joints corresponding to the first drive joint 57A and the first driven joint 58A are provided in the intermediate portion. Similarly, although not explicitly shown in the figure, the second universal joint mechanism 20B may be configured such that one end of the second connecting portion 59B is fixed to the lower end of the second output shaft 40B, the other end of the second connecting portion 59B is fixed to the other end in the direction of the axis O2 of the axle 37, and a single or multiple joints corresponding to the second driving joint 57B and the second driven joint 58B are provided in the intermediate portion.

[0065] In the drive wheel equipped with this power conversion mechanism 20, the rotational force of the first input member 36A and the second input member 36B is transmitted to the first output shaft 40A and the second output shaft 40B via the first spur gear 39A and the second spur gear 39B, and is transmitted from the first output shaft 40A and the second output shaft 40B to each end of the axle 37 via the first universal joint mechanism 20A and the second universal joint mechanism 20B. Then, this drive wheel can switch between the rotation and steering of the wheels 16 by adjusting the rotation speed of the first input member 36A and the second input member 36B. Therefore, since the universal joint mechanisms 20A and 20B are disposed at each end of the axle 37, respectively, the transmission system of the rotational force to the wheels 16 is simplified, the structure can be simplified, and this can contribute to a lower floor.

[0066] In the drive wheels 103, 103' of the above-mentioned embodiment, the first output shaft 40A and the axle 37 have axial directions that differ by 90 degrees. Therefore, in the drive wheels 103, 103', the first power conversion mechanism (first bevel gear mechanism 15A, first helical gear mechanism 17A, first worm gear mechanism 18A, first crown gear mechanism 19A, first universal joint mechanism 20A) that transmits the rotational force of the first output shaft 40A to one end of the axle 37 transmits the rotational force of the first output shaft 40A to one end of the axle 37 whose axial direction is different from that of the first output shaft 40A. In addition, in the drive wheels 103, 103' of the above-mentioned embodiment, the second output shaft 40B and the axle 37 have axial directions that differ by 90 degrees. Therefore, the drive wheels 103, 103' transmit the rotational force of the second output shaft 40B to one end of the axle 37 through a second power conversion mechanism (second bevel gear mechanism 15B, second helical gear mechanism 17B, second worm gear mechanism 18B, second crown gear mechanism 19B, and second universal joint mechanism 20B), which transmits the rotational force of the second output shaft 40B to one end of the axle 37 whose axis direction is different from that of the second output shaft 40B. Note that the power conversion mechanism is not limited to the above-mentioned configuration, and may be configured to transmit the rotational force of the output shafts 40A, 40B to the axle 37 whose axis direction is different from that of the output shafts 40A, 40B. [Explanation of symbols]

[0067] 15 Power conversion mechanism (bevel gear mechanism) 15A First bevel gear mechanism (first power conversion mechanism) 15B Second bevel gear mechanism (second power conversion mechanism) 16 wheels 17 Power conversion mechanism (helical gear mechanism) 17A First helical gear mechanism (first power conversion mechanism) 17B Second helical gear mechanism (second power conversion mechanism) 18 Power conversion mechanism (worm gear mechanism) 18A First worm gear mechanism (first power conversion mechanism) 18B Second worm gear mechanism (second power conversion mechanism) 19 Power conversion mechanism (crown gear mechanism) 19A First crown gear mechanism (first power conversion mechanism) 19B Second crown gear mechanism (second power conversion mechanism) 20 Power conversion mechanism (universal joint mechanism) 20A First universal joint mechanism (first power conversion mechanism) 20B Second universal joint mechanism (second power conversion mechanism) 30A First Input 30B Second input section 34 Swivel Axis 36A First input member 36B Second input member 37 Axle 39A First spur gear (first transmission mechanism) 39B Second spur gear (second transmission mechanism) 40A first output shaft 40B Second output shaft 100 Carts 101 Cart body 103,103' Drive wheels

Claims

1. A rotatable annular first input member; a second input member having an annular shape and arranged coaxially with the first input member but shifted in an axial direction, and rotatable independently of the first input member; A first output shaft and a second output shaft disposed on different axes; a first transmission mechanism that engages with an inner periphery of the first input member to transmit a rotational force of the first input member to the first output shaft; a second transmission mechanism that engages with an inner periphery of the second input member to transmit a rotational force of the second input member to the second output shaft; A wheel fixed to the axle; a first power conversion mechanism that transmits a rotational force of the first output shaft to one end of the axle; a second power conversion mechanism that transmits a rotational force of the second output shaft to the other end of the axle; a pivot shaft that rotatably supports the wheel via the axle; A drive wheel.

2. a first input portion that engages with an outer periphery of the first input member to input a rotational force to the first input member; a second input portion that engages with an outer periphery of the second input member to input a rotational force to the second input member; The drive wheel of claim 1 .

3. The drive wheel according to claim 1 or 2, wherein the first output shaft and the second output shaft are disposed on both sides of the wheel in an axial direction of the axle.

4. The drive wheel according to claim 1 , wherein the first power conversion mechanism and the second power conversion mechanism are disposed on both sides of the wheel in an axial direction of the axle.

5. The drive wheel according to any one of claims 1 to 4, wherein the first power conversion mechanism transmits the rotational force of the first output shaft to one end of the axle having a different axial direction from the first output shaft, and is any one of a bevel gear mechanism, a helical gear mechanism, a worm gear mechanism, a crown gear mechanism, or a universal joint mechanism, and the second power conversion mechanism transmits the rotational force of the second output shaft to one end of the axle having a different axial direction from the second output shaft, and is any one of a bevel gear mechanism, a helical gear mechanism, a worm gear mechanism, a crown gear mechanism, or a universal joint mechanism.

6. 6. The drive wheel according to claim 1, wherein the pivot shaft is arranged such that its axis is offset in a horizontal direction perpendicular to the axis of the axle relative to the rotation axis of the wheel, which intersects with the axis of the axle and runs along a vertical direction.

7. A drive wheel according to any one of claims 1 to 6; A carriage body to which the drive wheels are attached; A trolley equipped with:

Images