Drive wheel and carriage
The drive wheel design with coaxial input shafts, separate output shafts, and a shared conversion gear on one side of the axle addresses the complexity of existing systems, achieving a compact and efficient omnidirectional movement mechanism.
Patent Information
- Application Number
- JP2023216044
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2023-12-21
- Publication Date
- 2025-07-03
AI Technical Summary
Existing drive wheels with differential omnidirectional movement mechanisms have a complex transmission system configuration that hinders miniaturization.
A drive wheel design featuring a first and second input shaft coaxially arranged, separate output shafts, and a shared conversion driven gear on one side of the axle, with inclined output shafts and universal joints to reduce transmission system volume.
The design achieves a compact transmission system that supports omnidirectional movement while allowing for reduced volume and simplified structure, enabling efficient steering and rotation control.
Smart Images
Figure 2025099404000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to drive wheels and bogies.
Background Art
[0002] Patent Document 1 discloses a drive wheel and a bogie using the drive wheel. This drive wheel includes a first input shaft and a second input shaft arranged coaxially, a first output shaft and a second output shaft arranged on different axes, a first spur gear mechanism that transmits the rotational force of the first input shaft to the first output shaft, a second spur gear mechanism that transmits the rotational force of the second input shaft to the second output shaft, a wheel connected to an axle, a swivel shaft that rotatably supports the wheel via the axle, a first power conversion mechanism that transmits the rotational force of the first output shaft to one end of the axle, and a second power conversion mechanism that transmits the rotational force of the second output shaft to the other end of the axle.
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0004] The drive wheel described in Patent Document 1 includes a differential omnidirectional movement mechanism. While having such a differential omnidirectional movement mechanism, it is desirable to simplify its basic configuration as much as possible. Specifically, the drive wheel described in Patent Document 1 transmits the rotational force of the first output shaft to one end of the axle by the first power conversion mechanism and transmits the rotational force of the second output shaft to the other end of the axle by the second power conversion mechanism, and there are power conversion mechanisms on both sides of the wheel. Therefore, in a drive wheel having a differential omnidirectional movement mechanism, it is desirable to reduce the volume of the transmission system around the wheel for miniaturization.
[0005] The present disclosure has been made in view of the above problems, and an object thereof is to provide a drive wheel and a bogie that include a differential omnidirectional movement mechanism and can reduce the volume of the transmission system around the wheels.
Means for Solving the Problems
[0006] A drive wheel according to an aspect of the present disclosure for achieving the above object includes a first input shaft and a second input shaft arranged coaxially, a first output shaft and a second output shaft arranged on a separate shaft, an axle connected to the wheel, a first transmission mechanism for transmitting the rotational force of the first input shaft to the first output shaft, a second transmission mechanism for transmitting the rotational force of the second input shaft to the second output shaft, a first power conversion mechanism including a conversion driven gear provided together with the wheel and a first conversion drive gear meshing with the conversion driven gear and provided on the first output shaft, a second power conversion mechanism including the conversion driven gear and a second conversion drive gear meshing with the conversion driven gear and provided on the second output shaft, and a swivel shaft for rotatably supporting the wheel via the axle, wherein the conversion driven gear is provided only on one side of the axle, and the first conversion drive gear and the second conversion drive gear mesh with the conversion driven gear on one side with the plane including the axis of the axle as a boundary.
[0007] As a desirable aspect of the above drive wheel, at least one of the axis centers of the first output shaft and the second output shaft is provided to be inclined with respect to the axis centers of the first input shaft and the second input shaft via a universal joint.
[0008] As a desirable aspect of the above drive wheel, at least one of the axis centers of the first output shaft and the second output shaft is provided to be inclined with respect to the axis centers of the first input shaft and the second input shaft via an inclined shaft.
[0009] As a desirable aspect of the above drive wheel, the rotation axis of the wheel intersecting the axis of the axle and extending in the vertical direction is displaced in the horizontal direction intersecting the axis of the axle with respect to the axis of the swivel shaft.
[0010] A carriage according to one aspect of the present disclosure for achieving the above object includes any one of the drive wheels described above and a carriage body to which the drive wheel is attached.
Advantages of the Invention
[0011] According to the present disclosure, a differential type omnidirectional movement mechanism is provided, and the volume of the transmission system around the wheels can be reduced.
Brief Description of the Drawings
[0012]
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
Figure 6
Figure 7
Figure 8
Figure 9
Figure 10
Modes for Carrying Out the Invention
[0013] Hereinafter, with reference to the drawings, preferred embodiments of the drive wheels and the carriage according to the present disclosure will be described in detail. Note that the present invention is not limited by this embodiment, and when there are a plurality of embodiments, those configured by combining each embodiment are also included. In addition, the components in the embodiment include those that can be easily assumed by those skilled in the art, substantially the same components, and those within a so-called equivalent range.
[0014] FIG. 10 is a schematic diagram showing a configuration example of the carriage of the embodiment.
[0015] The carriage 100 includes a carriage body 101, a handle part 102, four drive wheels 110 (120), a power supply part 104, and a control device 105.
[0016] The carriage body 101 is, for example, a flat plate material and has a rectangular shape in plan view. The handle part 102 is fixed to one side in the longitudinal direction of the carriage body 101. Four drive wheels 110 are mounted at the four corners on the back side of the carriage body 101. The four drive wheels 110 are rotatable and steerable. In addition, the power supply part 104 and the control device 105 are mounted on the back surface between the front and rear drive wheels 110 of the carriage body 101. 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 a RAM. Therefore, in the carriage 100, the control device 105 controls the drive wheels 110.
[0017] The carriage body 101 constitutes a flat surface, and the object to be transported can be placed on the flat surface. That is, the carriage 100 can be configured as an automatic guided vehicle (AGV). In addition, the carriage 100 can be configured as a device that travels by arranging equipment along the flat surface of the carriage body 101. Examples of the device include various ones such as a hand lifter, a forklift, a picking robot, and medical equipment.
[0018] Note that the carriage 100 and the device are not limited to the configuration described above regarding the number and arrangement of the drive wheels 110. For example, in the four-wheel form described above, the carriage 100 and the device may have a pair of drive wheels 110 attached to the rear side of the carriage 100 and a pair of driven wheels attached to the front side of the carriage 100. Also, although not shown in the figures, in a form with three or more wheels, the carriage 100 and the device may have one drive wheel 110 and all other wheels being driven wheels. Also, although not shown in the figures, in a form with three or more wheels, the carriage 100 and the device may have no driven wheels and all wheels being drive wheels 110. That is, in a form with three or more wheels, the carriage 100 and the device only need to have at least one drive wheel 110.
[0019] [Embodiment 1 of Drive Wheel] FIG. 1 is a perspective view showing the basic configuration of the drive wheel according to Embodiment 1. FIG. 2 is a front view showing the basic configuration of the drive wheel according to Embodiment 1. FIG. 3 is a side view showing the basic configuration of the drive wheel according to Embodiment 1. FIG. 4 is a perspective view showing the drive system of the drive wheel according to Embodiment 1. FIG. 5 is a cross-sectional view (sectional view taken along line A-A in FIG. 3) showing the drive system of the drive wheel according to Embodiment 1. FIG. 6 is a cross-sectional view (sectional view taken along line B-B in FIG. 3) showing the drive system of the drive wheel according to Embodiment 1. FIG. 7 is a schematic diagram showing the driving force transmission path of the drive wheel according to Embodiment 1.
[0020] In the following description, among the first direction, the second direction, and the third direction that intersect each other, the first direction is referred to as the "front-rear direction X", the second direction is referred to as the "width direction Y", and the third direction is referred to as the "up-down direction Z". The front-rear direction X, the width direction Y, and the up-down direction Z are perpendicular to each other. The front-rear direction X typically corresponds to the direction along which the drive wheel 110 travels straight.
[0021] The drive wheel 110 has a main body 10 fixed to the carriage main body 101 of the carriage 100 as described above. Based on this main body 10, a drive mechanism 11, a swivel portion 12, a transmission mechanism 13, a power conversion mechanism 14, and a wheel 15 are provided.
[0022] The main body 10 is formed in a plate shape with its plate surfaces facing vertically. The drive mechanism 11 inputs a rotational force and is mainly provided above the main body 10. The swivel part 12 is mainly arranged below the main body 10. The transmission mechanism 13 transmits the rotational force input by the drive mechanism 11. The power conversion mechanism 14 transmits the rotational force of the transmission mechanism 13 to the wheels 15. The wheels 15 are single wheels, which are rotatable by the rotational force input via the drive mechanism 11, the transmission mechanism 13, and the power conversion mechanism 14, and can be steered by the swivel part 12.
[0023] The drive mechanism 11 includes a first belt drive mechanism 22A as a first drive mechanism and a second belt drive mechanism 22B as a second drive mechanism. The first belt drive mechanism 22A includes a first drive part 23A, a first drive pulley 24A, a first input shaft 25A, a first driven pulley 26A, and a first drive belt 27A. The first drive part 23A is composed of a motor. The first drive part 23A is fixed to the main body 10. The first drive part 23A has a drive shaft 23Aa that protrudes above the main body 10 and extends in the vertical direction. The first drive pulley 24A is fixed to the drive shaft 23Aa. The first input shaft 25A is provided to extend in the vertical direction so as to be parallel to the drive shaft 23Aa and is rotatably supported about the axis O1. The first driven pulley 26A is fixed to a portion of the first input shaft 25A that protrudes above the main body 10. The first driven pulley 26A and the first drive pulley 24A are arranged side by side in a direction perpendicular to the first input shaft 25A and the drive shaft 23Aa. The first drive belt 27A is formed in an annular shape and is wound around the first driven pulley 26A and the first drive pulley 24A. Therefore, in the first belt drive mechanism 22A, when the first drive part 23A drives, the first drive pulley 24A rotates, and this rotation is transmitted from the first drive pulley 24A to the first driven pulley 26A via the first drive belt 27A, causing the first input shaft 25A to rotate.
[0024] The second belt drive mechanism 22B includes a second drive unit 23B, a second drive pulley 24B, a second input shaft 25B, a second driven pulley 26B, and a second drive belt 27B. The second drive unit 23B is composed of a motor. The second drive unit 23B is fixed to the main body 10. The second drive unit 23B has a drive shaft 23Ba that protrudes above the main body 10 and extends in the vertical direction. The second drive pulley 24B is fixed to the drive shaft 23Ba. The second drive pulley 24B is formed to have the same diameter as the first drive pulley 24A. The second input shaft 25B is provided to extend in the vertical direction so as to be parallel to the drive shaft 23Ba, and is rotatably supported about the axis O1. The second input shaft 25B has a cylindrical shape and is disposed outside the first input shaft 25A so as to be inserted through the first input shaft 25A and rotate independently of the first input shaft 25A. The second driven pulley 26B is fixed to a portion of the second input shaft 25B that protrudes above the main body 10. The second driven pulley 26B is formed to have the same diameter as the first driven pulley 26A and is located below the first driven pulley 26A. The second driven pulley 26B and the second drive pulley 24B are provided side by side in a direction orthogonal to the second input shaft 25B and the drive shaft 23Ba. The second drive belt 27B is formed in an annular shape and is wound around the second driven pulley 26B and the second drive pulley 24B. Therefore, by driving the second drive unit 23B, the second belt drive mechanism 22B causes the second drive pulley 24B to rotate, and this rotation is transmitted from the second drive pulley 24B to the second driven pulley 26B via the second drive belt 27B, causing the second input shaft 25B to rotate.
[0025] The turning unit 12 includes a turning shaft 35 and a support portion 36. The turning shaft 35 has the center of a disc shape as the axis O1 and is rotatably supported via a bearing 45 (see FIG. 5) provided between the turning shaft 35 and the main body 10. Thereby, the turning shaft 35 is supported so as to be relatively rotatable about the axis O1 with respect to the main body 10.
[0026] As shown in FIG. 5, the swivel shaft 35 is disposed to penetrate vertically along the axis O1 through the first input shaft 25A of the first belt drive mechanism 22A, and is rotatably supported via a bearing 43. Therefore, the first input shaft 25A is supported so as to be relatively rotatable about the axis O1 with respect to the swivel shaft 35, and is also supported so as to be relatively rotatable about the axis O1 with respect to the main body 10. That is, the swivel shaft 35 is provided so as to be rotatable with respect to the main body 10 regardless of the rotation of the first input shaft 25A. For this reason, the drive wheel 110 of the embodiment can input a rotational force to the first input shaft 25A on the axis O1 which is the swivel axis of the wheel 15.
[0027] The swivel shaft 35 is disposed with the second input shaft 25B of the second belt drive mechanism 22B facing upward, and is rotatably supported via a bearing 46. The second input shaft 25B is inserted through the first input shaft 25A and is rotatably disposed outside the first input shaft 25A via a bearing 44. Therefore, the second input shaft 25B is supported so as to be relatively rotatable about the axis O1 with respect to the swivel shaft 35 via the first input shaft 25A, and is also supported so as to be relatively rotatable about the axis O1 with respect to the main body 10. That is, the swivel shaft 35 is provided so as to be rotatable with respect to the main body 10 regardless of the rotation of the second input shaft 25B. For this reason, the drive wheel 110 of the embodiment can input a rotational force to the second input shaft 25B on the axis O1 which is the swivel axis of the wheel 15. With such a configuration, the first input shaft 25A, the second input shaft 25B, and the swivel shaft 35 are rotatably disposed coaxially along the axis O1.
[0028] In the slewing unit 12, a support portion 36 is provided so as to extend downward at the lower part of the slewing shaft 35. As shown in FIGS. 5 and 6, the support portion 36 includes support members 36a and 36b disposed on both sides in the width direction Y of the wheel 15, a support member 36c disposed outside the support member 36b in the width direction Y, and a connecting member 36d connecting the support members 36b and 36c. The wheel 15 is provided on an axle 37 extending along the width direction Y along an axis O2 orthogonal to the direction (vertical direction Z) in which the axis O1 extends. In the embodiment, the wheel 15 is fixed to the axle 37. Each end portion of the axle 37 along the axis O2 is rotatably supported by the support members 36a and 36b via bearings 48 (see FIG. 6), respectively.
[0029] In the slewing unit 12, as shown in FIGS. 2 to 6, the support portion 36 supports the first output shaft 40A, the second output shaft 40B, and the intermediate shaft 30B.
[0030] The first output shaft 40A includes a first drive output shaft 40Aa, a first driven output shaft 40Ab, and a flexible output shaft 40Ac, as shown in FIGS. 2 to 4. The first drive output shaft 40Aa is provided along an axis O3a (see FIGS. 2 and 3) extending parallel to the direction (vertical direction Z) in which the axis O1 extends. The first drive output shaft 40Aa is rotatably supported about the axis O3a with respect to the slewing shaft 35 via a bearing (not shown). The first driven output shaft 40Ab is provided along an axis O3b (see FIGS. 2 and 3) that intersects the direction (vertical direction Z) in which the axis O3a extends and is inclined in the front-rear direction X. The first driven output shaft 40Ab is rotatably supported about the axis O3b with respect to the connecting member 36d of the support portion 36 via a bearing (not shown). The flexible output shaft 40Ac is constituted by a flexible joint. The flexible output shaft 40Ac connects the first drive output shaft 40Aa and the first driven output shaft 40Ab. Therefore, in the first output shaft 40A, the rotational forces of the first drive output shaft 40Aa and the first driven output shaft 40Ab are transmitted to each other by the flexible output shaft 40Ac.
[0031] As shown in FIGS. 3 to 4, the second output shaft 40B is linearly provided along an axis O4 (see FIGS. 3, 5, and 6) that extends parallel to the direction in which the axis O1 extends (vertical direction Z). As shown in FIG. 6, the second output shaft 40B is rotatably provided about the axis O4 via a bearing 47 with respect to a connecting member 36d of the swivel shaft 35 and the support portion 36.
[0032] In the drive wheel 110 of the embodiment, the first output shaft 40A (first driven output shaft 40Ab) and the second output shaft 40B have their respective axes O3b and O4 arranged about the axis O2 of the axle 37 at more than 0° and less than 90° within a range where the first conversion drive gear 41A and the second conversion drive gear 41B do not interfere with each other. Also, in terms of the capacity of the transmission force of the driving force, it is preferable to arrange the axes O3b and O4 of the first output shaft 40A (first driven output shaft 40Ab) and the second output shaft 40B about the axis O2 of the axle 37 at 45° or more and less than 90°.
[0033] As shown in FIGS. 4 and 6, the intermediate shaft 30B is linearly provided along an axis O8 (see FIG. 6) that extends parallel to the direction in which the axis O1 extends (vertical direction Z). As shown in FIG. 6, the intermediate shaft 30B is rotatably provided about the axis O8 via a bearing 49 with respect to the swivel shaft 35.
[0034] As shown in FIGS. 4 to 6, the transmission mechanism 13 includes a first transmission mechanism 13A and a second transmission mechanism 13B.
[0035] The first transmission mechanism 13A is also referred to as a first transmission gear mechanism. The first transmission mechanism 13A transmits the rotational force of the first input shaft 25A to the first output shaft 40A. The first transmission mechanism 13A includes a first drive gear 31A and a first driven gear 32A. In the drive wheel 110 of the embodiment, the first drive gear 31A and the first driven gear 32A are constituted by spur gears.
[0036] In the first transmission mechanism 13A, the first drive gear 31A is fixed to the first input shaft 25A. Therefore, the first drive gear 31A rotates about the axis O1 of the first input shaft 25A. The first driven gear 32A is fixed to the first drive output shaft 40Aa of the first output shaft 40A. Therefore, the first driven gear 32A rotates about the axis O3a of the first drive output shaft 40Aa. And the first drive gear 31A meshes with the first driven gear 32A. Therefore, the first transmission mechanism 13A transmits the rotational force of the first input shaft 25A from the first drive gear 31A to the first driven gear 32A to apply a rotational force to the first drive output shaft 40Aa of the first output shaft 40A. As described above, the first drive output shaft 40Aa is connected to the first driven output shaft 40Ab by the free output shaft 40Ac. Therefore, in the first output shaft 40A, the rotation about the axis O3a of the first drive output shaft 40Aa is transmitted as the rotation about the axis O3b of the first driven output shaft 40Ab.
[0037] The second transmission mechanism 13B is also referred to as the first transmission gear mechanism. The second transmission mechanism 13B transmits the rotational force of the second input shaft 25B to the second output shaft 40B. The second transmission mechanism 13B includes a second drive gear 31B, a second driven gear 32B, and a second connecting gear 33B. In the drive wheel 110 of the embodiment, the second drive gear 31B, the second driven gear 32B, and the second connecting gear 33B are constituted by spur gears.
[0038] In the second transmission mechanism 13B, the second drive gear 31B is fixed to the second input shaft 25B. Therefore, the second drive gear 31B rotates about the axis O1 of the second input shaft 25B. The second driven gear 32B is fixed to the intermediate shaft 30B. Therefore, the second driven gear 32B rotates about the axis O8 of the intermediate shaft 30B. The second connecting gear 33B is fixed to the second output shaft 40B. Therefore, the second connecting gear 33B rotates about the axis O4 of the second output shaft 40B. The second drive gear 31B meshes with the second driven gear 32B. The second driven gear 32B meshes with the second connecting gear 33B. Therefore, the second transmission mechanism 13B transmits the rotational force of the second input shaft 25B from the second drive gear 31B to the second driven gear 32B to apply a rotational force to the intermediate shaft 30B, and further transmits the rotational force of the intermediate shaft 30B from the second driven gear 32B to the second connecting gear 33B to apply a rotational force to the second output shaft 40B.
[0039] As shown in FIGS. 3 to 6, the power conversion mechanism 14 includes a first power conversion mechanism 14A and a second power conversion mechanism 14B.
[0040] The first power conversion mechanism 14A is also referred to as a first power conversion gear mechanism. The first power conversion mechanism 14A transmits the rotational force of the first output shaft 40A to the wheels 15. The first power conversion mechanism 14A includes a first conversion drive gear 41A and a conversion driven gear 42. In the drive wheel 110 of the embodiment, the first conversion drive gear 41A and the conversion driven gear 42 are constituted by bevel gears.
[0041] In the first power conversion mechanism 14A, the first conversion drive gear 41A is fixed to the first driven output shaft 40Ab of the first output shaft 40A. Therefore, the first conversion drive gear 41A rotates around the axis O3b together with the first driven output shaft 40Ab. Also, the conversion driven gear 42 is fixed only to one side in the direction of the axis O2 of the axle 37 to which the single wheel 15 is fixed. That is, the conversion driven gear 42 is arranged only on one side of the single wheel 15. Therefore, the conversion driven gear 42 rotates around the axis O2 together with the axle 37 and the wheel 15. And the first conversion drive gear 41A meshes with the conversion driven gear 42. Therefore, the first power conversion mechanism 14A transmits the rotational force of the first output shaft 40A from the first conversion drive gear 41A to the conversion driven gear 42 to apply a rotational force to the axle 37 and the wheel 15.
[0042] The second power conversion mechanism 14B is also referred to as the second power conversion gear mechanism. The second power conversion mechanism 14B transmits the rotational force of the second output shaft 40B to the wheel 15. The second power conversion mechanism 14B includes a second conversion drive gear 41B and a conversion driven gear 42. The conversion driven gear 42 is shared with the first power conversion mechanism 14A. In the drive wheel 110 of the embodiment, the second conversion drive gear 41B and the conversion driven gear 42 are constituted by bevel gears.
[0043] In the second power conversion mechanism 14B, the second conversion drive gear 41B is fixed to the second output shaft 40B. Therefore, the second conversion drive gear 41B rotates around the axis O4 together with the second output shaft 40B. And the second conversion drive gear 41B meshes with the conversion driven gear 42. Therefore, the second power conversion mechanism 14B transmits the rotational force of the second output shaft 40B from the second conversion drive gear 41B to the conversion driven gear 42 to apply a rotational force to the axle 37 and the wheel 15.
[0044] Here, as described above, the first output shaft 40A and the second output shaft 40B are arranged such that the centers of their axes O3b and O4 are located at more than 0° and less than 90° about the axis O2 of the axle 37 within a range where the first conversion drive gear 41A and the second conversion drive gear 41B do not interfere with each other. Therefore, the first conversion drive gear 41A and the second conversion drive gear 41B mesh with the conversion driven gear 42 on one side (upper side) with respect to the plane (horizontal plane) including the axis O2 of the axle 37 as a boundary.
[0045] In this power conversion mechanism 14, the first conversion drive gear 41A of the first power conversion mechanism 14A and the second conversion drive gear 41B of the second power conversion mechanism 14B have the same pitch circle diameter and the same number of teeth as each other.
[0046] Also, as shown in FIG. 3, in the drive wheel 110 of the embodiment, the rotation axis O5 of the wheel 15 along the vertical direction intersecting the axis O2 of the axle 37 is displaced (offset) in the horizontal direction (front-rear direction X) intersecting or orthogonal to the axis O1 of the turning shaft 35 with respect to the axis O2 of the axle 37. The rotation axis O5 of the wheel 15 is the center in the direction along the axis O2 of the axle 37 in the wheel 15 and is orthogonal to the axis O2.
[0047] This drive wheel 110 can rotate and steer the wheel 15 by rotating the first input shaft 25A and the second input shaft 25B by the drive mechanism 11. For example, when the first input shaft 25A is rotated, the second input shaft 25B is rotated in the opposite direction to the first input shaft 25A, and the rotational speeds (rotation speeds) of the first input shaft 25A and the second input shaft 25B are made the same, the wheel 15 can be rotated without being steered. At this time, by making the rotational speeds (rotation speeds) of the first input shaft 25A and the second input shaft 25B different, the wheel 15 can be steered while being rotated or stopped.
[0048] Here, the operation of the drive wheel 110 will be described. As shown in FIG. 7, when the drive wheel 110 rotates the first input shaft 25A in the A1 direction, the first drive gear 31A provided on the first input shaft 25A rotates in the same direction, and the first driven gear 32A meshing with the first drive gear 31A rotates in the A2 direction opposite to the A1 direction. Then, the first conversion drive gear 41A provided on the first output shaft 40A integrally with the first driven gear 32A rotates in the same direction. Then, the conversion driven gear 42 meshing with the first conversion drive gear 41A rotates in the C direction, and a rotational force in the C direction is applied to the axle 37 and the wheel 15 integrally with the conversion driven gear 42. On the other hand, when the drive wheel 110 rotates the second input shaft 25B in the B1 direction opposite to the A1 direction, the second drive gear 31B provided on the second input shaft 25B rotates in the same direction, and the second connection gear 33B meshing with the second driven gear 32B through the second driven gear 32B meshing with the second drive gear 31B rotates in the B2 direction in the same direction as the B1 direction. Then, the second conversion drive gear 41B provided on the second output shaft 40B integrally with the second connection gear 33B rotates in the same direction. Then, the conversion driven gear 42 meshing with the second conversion drive gear 41B rotates in the C direction, and a rotational force in the C direction is applied to the axle 37 and the wheel 15 integrally with the conversion driven gear 42.
[0049] At this time, when the drive wheel 110 reduces the rotational speed of the second input shaft 25B with respect to the rotational speed of the first input shaft 25A, the rotational speed input from the second conversion drive gear 41B to the axle 37 and the wheel 15 via the conversion driven gear 42 becomes lower than the rotational speed input from the first conversion drive gear 41A to the axle 37 and the wheel 15 via the conversion driven gear 42. Then, the swivel shaft 35 rotates by that rotational speed difference, and the wheel 15 swivels and steers. Also, when the drive wheel 110 stops the rotation of the first input shaft 25A or the second input shaft 25B, the rotational speed input from the first conversion drive gear 41A or the second conversion drive gear 41B to the axle 37 and the wheel 15 via the conversion driven gear 42 becomes 0, and the wheel 15 swivels and steers without rotating.
[0050] In addition, in the drive wheel 110 of the embodiment, in the second transmission mechanism 13B, it may be configured as a winding transmission mechanism. For example, the second drive gear 31B and the second connection gear 33B are configured as a pair of winding wheels, and an endless winding transmission member is wound around each winding wheel. Each winding wheel is configured by a pulley, and the winding transmission member is configured by a timing belt. Or, each winding wheel is configured by a sprocket, and the winding transmission member is configured by a chain. By configuring in this way, the intermediate shaft 30B and the second driven gear 32B can be eliminated, and the number of parts can be reduced.
[0051] The drive wheel 110 of the above-described embodiment is characterized by a first input shaft 25A and a second input shaft 25B arranged coaxially, a first output shaft 40A and a second output shaft 40B arranged on separate shafts, an axle 37 connected to the wheel 15, a first transmission mechanism 13A that transmits the rotational force of the first input shaft 25A to the first output shaft 40A, a second transmission mechanism 13B that transmits the rotational force of the second input shaft 25B to the second output shaft 40B, a conversion driven gear 42 provided together with the wheel 15, and a first conversion drive gear 41A that meshes with the conversion driven gear 42 and is provided on the first output shaft 40A (first driven output shaft 40Ab), including a first power conversion mechanism 14A, a second power conversion mechanism 14B including a conversion driven gear 42 and a second conversion drive gear 41B that meshes with the conversion driven gear 42 and is provided on the second output shaft 40B, and a swivel shaft 35 that rotatably supports the wheel 15 via the axle 37. The conversion driven gear 42 is provided only on one side of the axle 37, and the first conversion drive gear 41A and the second conversion drive gear 41B mesh with the conversion driven gear 42 on one side with the plane including the axis O2 of the axle 37 as a boundary.
[0052] This drive wheel 110 has a differential all-directional movement mechanism. That is, in the drive wheel 110, the rotational forces of the first input shaft 25A and the second input shaft 25B are transmitted to the first output shaft 40A and the second output shaft 40B via the first transmission mechanism 13A and the second transmission mechanism 13B, and are transmitted from the first output shaft 40A and the second output shaft 40B to the wheel 15 via the first power conversion mechanism 14A and the second power conversion mechanism 14B. This drive wheel 110 can switch between the rotation of the wheel 15 and the steering of the wheel 15 by adjusting the rotational speeds of the first input shaft 25A and the second input shaft 25B.
[0053] In particular, in this drive wheel 110, the first power conversion mechanism 14A and the second power conversion mechanism 14B have a common conversion driven gear 42 for transmitting the rotational force to the wheel 15. The conversion driven gear 42 is provided only on one side of the axle 37. The first conversion drive gear 41A and the second conversion drive gear 41B mesh with the conversion driven gear 42 on one side with the plane including the axis O2 of the axle 37 as the boundary. Therefore, in the prior art (for example, Patent Document 1), the rotational forces of the first output shaft and the second output shaft are transmitted to one end and the other end of the axle respectively. However, in this drive wheel 110, the first power conversion mechanism 14A and the second power conversion mechanism 14B transmit the rotational forces of the first output shaft 40A and the second output shaft 40B with the common conversion driven gear 42. Moreover, in this drive wheel 110, the conversion driven gear 42 is provided only on one side of the axle 37, and the first conversion drive gear 41A and the second conversion drive gear 41B mesh with the conversion driven gear 42 on one side with the plane including the axis O2 of the axle 37 as the boundary. For this reason, in this drive wheel 110, the first output shaft 40A (the first driven output shaft 40Ab) provided with the first conversion drive gear 41A and the second output shaft 40B provided with the second conversion drive gear 41B are both arranged closely to the common conversion driven gear 42. As a result, the drive wheel 110 of the embodiment can reduce the volume of the transmission system around the wheel 15.
[0054] In addition, for the drive wheel 110 of the embodiment, at least one of the first output shaft 40A and the second output shaft 40B has an axis O3b inclined with respect to the axis O1 of the swivel shaft 35, the first input shaft 25A, and the second input shaft 25B via a universal joint (universal output shaft 40Ac). In the drive wheel 110 of the embodiment, the first output shaft 40A is provided inclined with respect to the axis O1 via the universal output shaft 40Ac, but the second output shaft 40B (or both) may be provided inclined with respect to the axis O1 via a universal joint.
[0055] According to this drive wheel 110, a configuration can be implemented in which the first conversion drive gear 41A and the second conversion drive gear 41B mesh with the conversion driven gear 42 on one side with the plane including the axis O2 of the axle 37 as a boundary, and the effect of reducing the volume of the transmission system around the wheel 15 can be obtained.
[0056] Further, the drive wheel 110 of the embodiment arranges the rotation axis O5 of the wheel 15 along the vertical direction intersecting the axis O2 of the axle 37 so as to be displaced in the horizontal direction intersecting the axis O2 of the axle 37 with respect to the axis O1 of the swivel shaft 35.
[0057] According to this drive wheel 110, when the wheel 15 is not being driven, the wheel 15 can be passively swiveled by an external force acting in the horizontal direction. That is, the carriage 100 can be automatically traveled and automatically steered, and an operator can manually travel and manually steer.
[0058] In addition, the carriage 100 of the embodiment includes the above-described drive wheel 110 and a carriage body 101 to which the drive wheel 110 is attached. Therefore, the carriage 100 can simplify the basic structure.
[0059] In the above-described drive wheel 110, the gear described as a spur gear may be configured by, for example, a helical gear. Also, in the above-described drive wheel 110, the gear described as a bevel gear may be configured by, for example, a crown gear.
[0060] [Second Embodiment of Drive Wheel] FIG. 8 is a perspective view showing the drive system of the drive wheel according to Embodiment 2. FIG. 9 is a schematic diagram showing the driving force transmission path of the drive wheel according to Embodiment 2.
[0061] The drive wheel 120 of Embodiment 2 is mainly different from the drive wheel 110 of Embodiment 1 described above in the configuration of the first output shaft 40A, and other configurations are equivalent. In the following description of the drive wheel 120 of Embodiment 2, the same reference numerals are given to the equivalent parts as those of the drive wheel 110 of Embodiment 1, and the description thereof is omitted.
[0062] As shown in FIG. 8, the first output shaft 40A is formed linearly, and its axis O3 is provided so as to be inclined with respect to the axis O1 of the turning shaft 35, the first input shaft 25A, and the second input shaft 25B. The first output shaft 40A is configured as an inclined shaft that is inclined with respect to the axis O1. The first output shaft 40A is rotatably supported about the axis O3 via a bearing (not shown) with respect to the connecting member 36d of the turning shaft 35 and the support portion 36. The first output shaft 40A is the first power conversion mechanism 14A, and a first conversion drive gear 41A that meshes with a conversion driven gear 42 provided on the axle 37 is fixed thereto. Therefore, the first power conversion mechanism 14A transmits the rotational force of the first output shaft 40A from the first conversion drive gear 41A to the conversion driven gear 42 to apply a rotational force to the axle 37 and the wheel 15.
[0063] In configuring the drive wheel 120 with the first output shaft 40A as an inclined shaft, the configuration of the first transmission mechanism 13A is changed. The first transmission mechanism 13A includes a first drive gear 31A and a first driven gear 32A, similar to the drive wheel 110, but is configured with helical gears instead of spur gears. Therefore, the first transmission mechanism 13A transmits the rotational force of the first input shaft 25A to the first output shaft 40A.
[0064] The drive wheel 120 of Embodiment 2 configured as described above and the carriage 100 using the drive wheel 120 exhibit the same operational effects as the drive wheel 110 and the carriage 100 of Embodiment 1 described above.
[0065] In the driving wheel 120 of the embodiment, the first output shaft 40A is provided inclined with respect to the axis O1 as an inclined shaft. However, the second output shaft 40B (or both) may be provided inclined with respect to the axis O1 as an inclined shaft. That is, in the driving wheel 120 of the embodiment, at least one of the axis centers O3 and O4 of the first output shaft 40A and the second output shaft 40B is provided inclined with respect to the axis center O1 of the first input shaft 25A and the second input shaft 25B via the inclined shaft. Further, when the second output shaft 40B is configured as an inclined shaft, the second transmission mechanism 13B includes a second driving gear 31B, a second driven gear 32B, and a second connecting gear 33B, similar to the driving wheel 110, but is configured with a helical gear instead of a spur gear. Further, in the driving wheel 120 of the embodiment, the gears described as bevel gears may be configured with crown gears, for example.
Explanation of Signs
[0066] 13A First transmission mechanism 13B Second transmission mechanism 14A First power conversion mechanism 14B Second power conversion mechanism 15 Wheel 25A First input shaft 25B Second input shaft 37 Axle 40Ac Free output shaft (universal joint) 40A First output shaft 40B Second output shaft 41A First conversion driving gear 41B Second conversion driving gear 42 Conversion driven gear 100 Carriage 101 Carriage body 110,120 Driving wheel
Claims
1. A first input shaft and a second input shaft arranged coaxially, a first output shaft and a second output shaft arranged on different axes, an axle connected to a wheel, a first transmission mechanism for transmitting the rotational force of the first input shaft to the first output shaft, a second transmission mechanism for transmitting the rotational force of the second input shaft to the second output shaft, a first power conversion mechanism including a conversion driven gear provided together with the wheel and a first conversion drive gear meshing with the conversion driven gear and provided on the first output shaft, a second power conversion mechanism including the conversion driven gear and a second conversion drive gear meshing with the conversion driven gear and provided on the second output shaft, a swivel shaft for rotatably supporting the wheel via the axle, comprising, the conversion driven gear is provided only on one side of the axle, the first conversion drive gear and the second conversion drive gear mesh with the conversion driven gear on one side with respect to a plane including the axis of the axle, a drive wheel.
2. The first output shaft and the second output shaft are provided such that at least one of their axes is inclined with respect to the axes of the first input shaft and the second input shaft via a universal joint, The drive wheel according to Claim 1.
3. The first output shaft and the second output shaft are provided such that at least one of their axes is inclined with respect to the axes of the first input shaft and the second input shaft via an inclined shaft, The drive wheel according to Claim 1.
4. The rotational axis of the wheel along the vertical direction intersecting the axis of the axle is displaced in the horizontal direction intersecting the axis of the axle with respect to the axis of the swivel shaft, The drive wheel according to Claim 1.
5. A drive wheel, a bogie body to which the drive wheel is attached, comprising, the drive wheel, a first input shaft and a second input shaft arranged coaxially, a first output shaft and a second output shaft arranged on different axes, an axle connected to a wheel, a first transmission mechanism for transmitting the rotational force of the first input shaft to the first output shaft, a second transmission mechanism for transmitting the rotational force of the second input shaft to the second output shaft, a first power conversion mechanism including a conversion driven gear provided together with the wheel and a first conversion drive gear meshing with the conversion driven gear and provided on the first output shaft, a second power conversion mechanism including the conversion driven gear and a second conversion drive gear meshing with the conversion driven gear and provided on the second output shaft, a swivel shaft for rotatably supporting the wheel via the axle, comprising, the conversion driven gear is provided only on one side of the axle, The first conversion drive gear and the second conversion drive gear mesh with the conversion driven gear on one side with respect to a plane including the axis of the axle. Bogie.
Citation Information
Patent Citations
Drive wheel and bogie
JP2020024033A