Driving wheel and carriage

Abstract

To stabilize traveling while suppressing complication of support constitution of a wheel.SOLUTION: A driving wheel 110 includes: a body 10; a first wheel 15A and a second wheel 15B coaxially having axles 37A and 37b; a turning part 12 turnably supporting each of the wheels 15A and 15B on the body 10; a first driving part 21A imparting a torque to the first wheel 15A; a second driving part 21B imparting a torque to the second wheel 15B; and a turning driving part 22 imparting torque to the turning part 12.SELECTED DRAWING: Figure 2

Description

[Technical field]

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

[0002] For example, the drive wheel (wheel drive device) described in Patent Document 1 has a first rotating shaft, a second rotating shaft, and a swivel shaft coaxially arranged, a first wheel and a second wheel that can rotate around a horizontal axis at a position offset from the swivel shaft, a suspension part that presses the first wheel and the second wheel toward the road surface, and a first motor transmits rotation from the first rotating shaft to the first wheel, and a second motor transmits rotation from the second rotating shaft to the second wheel. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2016-049921 A Summary of the Invention [Problem to be solved by the invention]

[0004] As described in Patent Document 1, a dual-wheel drive wheel having a first wheel and a second wheel can turn by driving each wheel and changing the number of rotations of the drive to each wheel. In such a configuration, if one of the wheels spins or leaves the ground, an unintended turning force is generated, which impairs the stability of straight-line running. Conversely, when turning is required, turning in the intended direction is not possible unless both wheels are in contact with the ground. For this reason, a suspension part is sometimes provided as in the drive wheel described in Patent Document 1, but this creates a problem of a complicated wheel support configuration.

[0005] The present disclosure has been made in consideration of the above-mentioned problems, and aims to provide a drive wheel and bogie that can stabilize driving while minimizing the complexity of the wheel support structure. [Means for solving the problem]

[0006] In order to achieve the above-mentioned object, a drive wheel of one embodiment of the present disclosure includes a main body, a first wheel and a second wheel having coaxial axles, a turning unit that supports each of the wheels rotatably relative to the main body, a first drive unit that imparts a rotational force to the first wheel, a second drive unit that imparts a rotational force to the second wheel, and a turning drive unit that imparts a rotational force to the turning unit.

[0007] A desirable aspect of the above-mentioned drive wheel is one in which the first drive unit and the second drive unit are provided on the rotating unit, and includes a first transmission mechanism that transmits the rotational force of the first drive unit to the first wheel, and a second transmission mechanism that transmits the rotational force of the second drive unit to the second wheel.

[0008] A desirable aspect of the above-mentioned drive wheel is one in which the first drive unit and the second drive unit are provided on the main body, and includes a first transmission mechanism that transmits the rotational force of the first drive unit to the first wheel, and a second transmission mechanism that transmits the rotational force of the second drive unit to the second wheel.

[0009] In a preferred embodiment of the drive wheels, the rotational axis of each wheel, which is aligned vertically and perpendicular to the axis of each axle, is shifted horizontally relative to the axis of the turning portion, which is perpendicular to the axis of the axle.

[0010] In order to achieve the above object, a bogie according to one aspect of the present disclosure includes any one of the drive wheels described above and a bogie body to which the drive wheel is attached. Effect of the Invention

[0011] According to the present disclosure, it is possible to stabilize driving while minimizing the complexity of the wheel support structure. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a perspective view showing a basic configuration of a drive wheel according to the first embodiment. [Diagram 2] FIG. 2 is a front view showing the basic configuration of the drive wheel of the first embodiment. [Diagram 3] FIG. 3 is a side view showing the basic configuration of the drive wheel of the first embodiment. [Figure 4] FIG. 4 is a bottom view showing the basic configuration of the drive wheel of the first embodiment. [Diagram 5] FIG. 5 is a perspective view showing a drive system for the drive wheels of the first embodiment. [Figure 6] FIG. 6 is a cross-sectional view showing a drive system for a drive wheel according to the first embodiment. [Figure 7] FIG. 7 is a cross-sectional view showing a drive system for the drive wheels of the first embodiment. [Figure 8] FIG. 8 is a schematic diagram showing a driving force transmission path of the driving wheels in the first embodiment. [Figure 9] FIG. 9 is a perspective view showing a drive system for drive wheels according to the second embodiment. [Figure 10] FIG. 10 is a front view showing the basic configuration of a drive wheel according to the second embodiment. [Figure 11] FIG. 11 is a side view showing the basic configuration of a drive wheel according to the second embodiment. [Figure 12] FIG. 12 is a bottom view showing the basic configuration of the drive wheel of the second embodiment. [Figure 13] FIG. 13 is a perspective view showing a drive system for drive wheels according to the second embodiment. [Figure 14] FIG. 14 is a cross-sectional view showing a drive system for a drive wheel according to the second embodiment. [Figure 15] FIG. 15 is a cross-sectional view showing a drive system for a drive wheel according to the second embodiment. [Figure 16] FIG. 16 is a cross-sectional view showing a drive system for a drive wheel according to the second embodiment. [Figure 17] FIG. 17 is a schematic diagram showing a driving force transmission path of a driving wheel in the second embodiment. [Figure 18] FIG. 18 is a schematic diagram illustrating a configuration example of a cart according to an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Preferred embodiments of the drive wheel and the bogie according to the present disclosure will be described in detail below with reference to the drawings. Note that the present invention is not limited to these embodiments, and when there are multiple embodiments, the present invention also includes a configuration in which each embodiment is combined. Furthermore, the components in the 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.

[0014] FIG. 18 is a schematic diagram illustrating a configuration example of a cart according to an embodiment.

[0015] The cart 100 includes a cart body 101 , a handle portion 102 , four drive wheels 110 ( 120 ), a power supply portion 104 , and a control device 105 .

[0016] 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 110 are attached to the four corners of the rear surface of the dolly body 101. The four drive wheels 110 are rotatable and steerable. In addition, 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 110. 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. Thus, in the dolly 100, the control device 105 controls the drive wheels 110.

[0017] 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.

[0018] The number and arrangement of the drive wheels 110 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 110 attached to the rear side of the dolly 100 and a pair of driven wheels attached to the front 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 110 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 110. In other words, in a configuration with three or more wheels, the dolly 100 and the device may have at least one drive wheel 110.

[0019] [Driving Wheel Embodiment 1] FIG. 1 is a perspective view showing the basic configuration of a drive wheel of the first embodiment. FIG. 2 is a front view showing the basic configuration of a drive wheel of the first embodiment. FIG. 3 is a side view showing the basic configuration of a drive wheel of the first embodiment. FIG. 4 is a bottom view showing the basic configuration of a drive wheel of the first embodiment. FIG. 5 is a perspective view showing a drive system of a drive wheel of the first embodiment. FIG. 6 is a cross-sectional view (cross-sectional view taken along line AA in FIG. 2) showing the drive system of a drive wheel of the first embodiment. FIG. 7 is a cross-sectional view (cross-sectional view taken along line BB in FIG. 3) showing the drive system of a drive wheel of the first embodiment. FIG. 8 is a schematic diagram showing a drive force transmission path of a drive wheel of the first embodiment.

[0020] In the following description, of the first, second, and third directions that intersect with 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 moves straight. In FIG. 1, the front-rear direction X, the width direction Y, and the up-down direction Z are shown by double-headed arrows, but in other figures, they are shown in a coordinate system with single-headed arrows.

[0021] The drive wheel 120 has a body 10 fixed to the cart body 101 of the cart 100 as described above, and based on this body 10, a drive mechanism 11, a turning part 12, a transmission mechanism 13, and wheels 15 are provided.

[0022] The main body 10 is formed in a plate shape with the plate surfaces facing up and down. The swivel unit 12 is provided to be rotatable with respect to the main body 10, and is mainly disposed below the main body 10. The drive mechanism 11 inputs a rotational force, and is provided in the swivel unit 12 in the case of the drive wheel 110 of the embodiment. The transmission mechanism 13 transmits the rotational force input by the drive mechanism 11 to the wheels 15. The wheels 15 are twin wheels, which are freely rotatable by the rotational force input via the drive mechanism 11 and the transmission mechanism 13, and can be steered by the swivel unit 12.

[0023] The swivel unit 12 includes a swivel shaft 35, a support unit 36, and a swivel drive unit 22. The swivel shaft 35 has an axis O1 (see FIGS. 3, 4, 6, and 7) at the center of its circle, and is rotatably supported via a bearing 45 (see FIGS. 6 and 7) provided on the outer periphery of the main body 10. This allows the swivel shaft 35 to be supported so as to be rotatable relatively to the main body 10 around the axis O1.

[0024] The support part 36 is disposed integrally below the pivot shaft 35. The support part 36 is provided with the wheel 15. The wheel 15 is a twin wheel as described above, and includes a first wheel 15A and a second wheel 15B. The first wheel 15A is provided integrally with a first axle 37A extending in the width direction Y along an axis O2 (FIGS. 2 to 4, 6 and 7) perpendicular to the direction in which the axis O1 extends (vertical direction Z). The first axle 37A extends along the axis O2 on one side of the width direction Y of the support part 36, and is rotatably supported by the support part 36 via a bearing 48A (see FIG. 7). The second wheel 15B is provided integrally with a second axle 37B extending in the width direction Y along an axis O2 perpendicular to the direction in which the axis O1 extends (vertical direction Z). The second axle 37B extends along the axis O2 on the other side of the support portion 36 in the width direction Y, and is rotatably supported on the support portion 36 via a bearing 48B (see FIG. 7). Therefore, the first wheel 15A and the second wheel 15B are provided rotatably on the support portion 36 about the coaxial axis O2 via the first axle 37A and the second axle 37B. In the driving wheel 110 of the embodiment, the first wheel 15A and the second wheel 15B have the same diameter.

[0025] The swivel drive unit 22 is composed of a motor. The swivel drive unit 22 is attached to the main body 10 so that an axis O9 (see Figs. 3 and 6) of the swivel drive shaft 22a extends along the vertical direction Z. A swivel drive gear 23 is fixed to the swivel drive shaft 22a. Therefore, the swivel drive gear 23 rotates about the axis O9 of the swivel drive shaft 22a by the rotational force generated by the swivel drive unit 22.

[0026] The revolving driven gear 24 is fixed to the revolving shaft 35. The revolving driven gear 24 is formed in an annular shape, and is supported together with the revolving shaft 35 so as to be rotatable relative to the main body 10 about the axis O1. The revolving driven gear 24 has meshing teeth on its annular outer surface. The meshing teeth of the revolving driven gear 24 mesh with the revolving drive gear 23. Therefore, the rotational force generated by the revolving drive unit 22 is transmitted to the revolving driven gear 24 via the revolving drive gear 23, and the revolving driven gear 24 rotates about the axis O1 together with the revolving shaft 35. In the driving wheel 110 of the embodiment, the revolving drive gear 23 and the revolving driven gear 24 are configured as spur gears.

[0027] The driving mechanism 11 has a first driving unit 21A and a second driving unit 21B.

[0028] The first driving unit 21A is configured with a motor. The first driving unit 21A is attached to the support part 36 so that the axis O6 (see FIG. 4) of the first driving shaft 21Aa extends along the width direction Y.

[0029] The second driving unit 21B is configured with a motor. The second driving unit 21B is attached to the support part 36 so that the axis O7 (see FIG. 4) of the second driving shaft 21Ba extends along the width direction Y. Therefore, the axis O6 of the first driving shaft 21Aa and the axis O7 of the second driving shaft 21Ba are provided in parallel.

[0030] The first driving unit 21A and the second driving unit 21B are provided side by side in the front-rear direction X. The first driving unit 21A and the second driving unit 21B are provided with the first driving shaft 21Aa and the second driving shaft 21Ba facing each other in opposite directions in the width direction Y. That is, the first driving unit 21A is provided with a tip of the first driving shaft 21Aa facing one side in the width direction Y, and the second driving unit 21B is provided with a tip of the second driving shaft 21Ba facing the other side in the width direction Y.

[0031] As shown in FIGS. 2 to 7, the transmission mechanism 13 has a first transmission mechanism 13A and a second transmission mechanism 13B.

[0032] 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 drive shaft 21Aa to the first wheel 15A. 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 configured by spur gears.

[0033] In the first transmission mechanism 13A, the first driving gear 31A is fixed to the first driving shaft 21Aa of the first driving unit 21A. Therefore, the first driving gear 31A rotates around the axis O6 of the first driving shaft 21Aa by the rotational force of the first driving unit 21A. The first driven gear 32A is fixed to the first wheel 15A around the axis O2 of the first axle 37A. Therefore, the first driven gear 32A rotates together with the first wheel 15A around the axis O2 of the first axle 37A. The first driving gear 31A is meshed with the first driven gear 32A. Therefore, the first transmission mechanism 13A transmits the rotational force of the first driving unit 21A from the first driving gear 31A to the first driven gear 32A to provide the rotational force to the first wheel 15A.

[0034] The second transmission mechanism 13B is also referred to as a second transmission gear mechanism. The second transmission mechanism 13B transmits the rotational force of the second drive shaft 21Ba to the second wheel 15B. The second transmission mechanism 13B includes a second drive gear 31B and a second driven gear 32B. In the drive wheel 110 of the embodiment, the second drive gear 31B and the second driven gear 32B are configured by spur gears.

[0035] In the second transmission mechanism 13B, the second driving gear 31B is fixed to the second driving shaft 21Ba of the second driving unit 21B. Therefore, the second driving gear 31B rotates around the axis O7 of the second driving shaft 21Ba by the rotational force of the second driving unit 21B. The second driven gear 32B is fixed to the second wheel 15B around the axis O2 of the second axle 37B. Therefore, the second driven gear 32B rotates together with the second wheel 15B around the axis O2 of the second axle 37B. The second driving gear 31B is meshed with the second driven gear 32B. Therefore, the second transmission mechanism 13B transmits the rotational force of the second driving unit 21B from the second driving gear 31B to the second driven gear 32B to provide the rotational force to the second wheel 15B.

[0036] In this transmission mechanism 13, the first driving gear 31A of the first transmission mechanism 13A and the second driving gear 31B of the second transmission mechanism 13B have the same pitch circle diameter and the same number of teeth. Also, in the transmission mechanism 13, the first driven gear 32A of the first transmission mechanism 13A and the second driven gear 32B of the second transmission mechanism 13B have the same pitch circle diameter and the same number of teeth.

[0037] As shown in Figs. 3, 4, 6 and 7, the driving wheel 110 of the embodiment is arranged such that the rotation axis O5 of the wheel 15 along the vertical direction perpendicular to the axis O2 of each axle 37A, 37B coincides with the axis O1 of the turning shaft 35. The rotation axis O5 of the wheel 15 passes through the center between the wheels 15A, 15B in the twin wheels 15A, 15B and is perpendicular to the axis O2. Although not shown in the figures, the driving wheel 110 of the embodiment may be arranged such that the rotation axis O5 of the wheel 15 along the vertical direction perpendicular to the axis O2 of each axle 37A, 37B is shifted (offset) from the axis O1 of the turning shaft 35 in the horizontal direction (front-rear direction X) that intersects or is perpendicular to the axis O2 of each axle 37A, 37B. In this case, the drive wheel 110 is arranged such that the component arranged on the support portion 36 is shifted (offset) in the horizontal direction (front-rear direction X).

[0038] The driving wheel 110 can rotate the wheels 15 by the driving mechanism 11. For example, by driving the first driving unit 21A and the second driving unit 21B to rotate the wheels 15A and 15B in the same direction and by making the number of rotations (rotation speeds) of the wheels 15A and 15B the same, the wheels 15A and 15B can rotate without steering. In addition, the driving wheel 110 can steer the wheels 15 by the swivel unit 12. For example, by driving the swivel driving unit 22, the wheels 15A and 15B can swivel around the axis O1 together with the swivel shaft 35 and the support unit 36 ​​relative to the main body 10, thereby steering the wheels 15A and 15B.

[0039] Here, the operation of the drive wheel 110 will be described with reference to FIG. 8. For convenience, FIG. 8 shows the meshing between the first drive gear 31A and the first driven gear 32A, and the meshing between the second drive gear 31B and the second driven gear 32B, expanded in the vertical direction. As shown in FIG. 8, when the first drive shaft 21Aa of the drive wheel 110 rotates in the A1 direction, the first drive gear 31A provided on the first drive shaft 21Aa rotates in the same direction, and the first driven gear 32A meshing with the first drive gear 31A rotates in the C1 direction opposite to the A1 direction. Then, the first axle 37A rotates in the same direction integrally with the first driven gear 32A. Then, a rotational force in the C1 direction is applied to the first wheel 15A integral with the first axle 37A. On the other hand, when the second drive shaft 21Ba rotates in the B1 direction, the second drive gear 31B provided on the second drive shaft 21Ba rotates in the same direction, and the second driven gear 32B meshing with the second drive gear 31B rotates in the C2 direction opposite to the B1 direction. Then, the second axle 37B rotates in the same direction together with the second driven gear 32B. Then, a rotational force in the C1 direction is applied to the second wheel 15B integrated with the second axle 37B.

[0040] At this time, the driving wheel 110 rotates the turning drive shaft 22a, causing the turning driven gear 24 meshing with the turning drive gear 23 integral with the turning drive shaft 22a to rotate in the direction D. Then, the turning shaft 35 rotates in the same direction integrally with the turning driven gear 24. Then, the wheel 15 is turned and steered by the amount of the rotation.

[0041] In addition, the drive wheels 110 are arranged so that the rotation axis O5 of the wheels 15, which is perpendicular to the axis O2 of the axles 37A and 37B and aligned along the vertical direction, coincides with the axis O1 of the turning shaft 35, so that the wheels 15 do not passively turn due to an external force acting from the horizontal direction. On the other hand, in the drive wheels 110 of the embodiment, if the rotation axis O5 of the wheels 15, which is perpendicular to the axis O2 of the axles 37A and 37B and aligned along the vertical direction, is offset from the axis O1 of the turning shaft 35 in the horizontal direction (front-rear direction X) that intersects or is perpendicular to the axis O2 of the axles 37A and 37B, when the first driving unit 21A, the second driving unit 21B, and the turning driving unit 22 are not driven, the wheels 15 turn passively due to an external force acting from the horizontal direction, and the operator can manually travel and steer the vehicle.

[0042] The drive wheel 110 of the above-described embodiment is characterized by including a main body 10, a first wheel 15A and a second wheel 15B having axles 37A and 37B coaxially arranged therewith, a turning unit 12 that supports each wheel 15A, 15B so that they can turn relative to the main body 10, a first driving unit 21A that imparts a rotational force to the first wheel 15A, a second driving unit 21B that imparts a rotational force to the second wheel 15B, and a turning driving unit 22 that imparts a rotational force to the turning unit 12.

[0043] The driving wheel 110 applies a rotational force to the first wheel 15A of the twin wheels by the first driving unit 21A, applies a rotational force to the other second wheel 15B by the second driving unit 21B, and applies a rotational force to the turning unit 12 by the turning driving unit 22. Therefore, the driving wheel 110 drives the wheels 15A and 15B to travel by the first driving unit 21A and the second driving unit 21B, and drives the turning by the turning driving unit 22 separately from the travel. Therefore, according to the driving wheel 110, no turning force is generated unintentionally during travel, and the stability of straight travel can be ensured. And, since the driving wheel 110 drives each wheel 15A and 15B by the first driving unit 21A and the second driving unit 21B, respectively, there is no need to provide a differential gear between the wheels 15A and 15B. Moreover, since the driving wheel 110 drives the turning by the turning driving unit 22 separately from the travel, a suspension unit as in the conventional example (for example, Patent Document 1) is not required. As a result, according to the driving wheel 110 of the embodiment, it is possible to stabilize the running while suppressing the complication of the support structure for the wheels 15A, 15B.

[0044] In the driving wheel 110 of the embodiment, the first driving portion 21A and the second driving portion 21B are provided on the turning portion 12.

[0045] By providing the first driving unit 21A and the second driving unit 21B on the rotating unit 12 that supports the wheels 15A, 15B, this driving wheel 110 can reduce the complexity of the configuration of the transmission mechanism 13 (first transmission mechanism 13A) that transmits rotational force from the first driving unit 21A to the first wheel 15A, and the transmission mechanism 13 (second transmission mechanism 13B) that transmits rotational force from the second driving unit 21B to the second wheel 15B.

[0046] Moreover, the bogie 100 of the embodiment includes the above-mentioned drive wheels 110 and the bogie body 101 to which the drive wheels 110 are attached. Therefore, the bogie 100 can stabilize its running while preventing the support structure for the wheels 15A and 15B from becoming complicated.

[0047] [Driving Wheel Embodiment 2] FIG. 9 is a perspective view showing a drive system of a drive wheel of the second embodiment. FIG. 10 is a front view showing a basic configuration of a drive wheel of the second embodiment. FIG. 11 is a side view showing a basic configuration of a drive wheel of the second embodiment. FIG. 12 is a bottom view showing a basic configuration of a drive wheel of the second embodiment. FIG. 13 is a perspective view showing a drive system of a drive wheel of the second embodiment. FIG. 14 is a cross-sectional view (CC cross-sectional view of FIG. 10) showing a drive system of a drive wheel of the second embodiment. FIG. 15 is a cross-sectional view (DD cross-sectional view of FIG. 11) showing a drive system of a drive wheel of the second embodiment. FIG. 16 is a cross-sectional view (EE cross-sectional view of FIG. 11) showing a drive system of a drive wheel of the second embodiment. FIG. 17 is a schematic diagram showing a drive force transmission path of a drive wheel of the second embodiment.

[0048] In the following description of the drive wheel 120 of the second embodiment, parts equivalent to those of the drive wheel 110 of the first embodiment are given the same reference numerals.

[0049] The drive wheel 120 has a body 10 fixed to the cart body 101 of the cart 100 as described above, and based on this body 10, a drive mechanism 11, a turning part 12, a transmission mechanism 13, and wheels 15 are provided.

[0050] The main body 10 is formed in a plate shape with the plate surfaces facing up and down. The swivel unit 12 is provided to be rotatable with respect to the main body 10, and is mainly disposed below the main body 10. The drive mechanism 11 inputs a rotational force, and is provided on the main body 10 in the case of the drive wheel 120 of the embodiment. The transmission mechanism 13 transmits the rotational force input by the drive mechanism 11 to the wheels 15. The wheels 15 are twin wheels, which are freely rotatable by the rotational force input via the drive mechanism 11 and the transmission mechanism 13, and can be steered by the swivel unit 12.

[0051] The swivel unit 12 includes a swivel shaft 35, a support unit 36, and a swivel drive unit 22. The swivel shaft 35 has an axis O1 (see Figs. 11, 12, 14, and 15) at the center of its circle, and is rotatably supported via a bearing 45 (see Figs. 14 to 16) provided on the outer periphery of the main body 10. As a result, the swivel shaft 35 is supported so as to be rotatable relatively to the main body 10 around the axis O1.

[0052] The support part 36 is disposed integrally below the pivot shaft 35. The support part 36 is provided with the wheel 15. The wheel 15 is a twin wheel as described above, and includes a first wheel 15A and a second wheel 15B. The first wheel 15A is provided integrally with a first axle 37A extending in the width direction Y along an axis O2 (FIGS. 10 to 12, 15 and 16) perpendicular to the direction in which the axis O1 extends (vertical direction Z). The first axle 37A extends along the axis O2 on one side of the width direction Y of the support part 36, and is rotatably supported by the support part 36 via a bearing 48A (see FIG. 16). The second wheel 15B is provided integrally with a second axle 37B extending in the width direction Y along an axis O2 perpendicular to the direction in which the axis O1 extends (vertical direction Z). The second axle 37B extends along the axis O2 on the other side of the support portion 36 in the width direction Y, and is rotatably supported on the support portion 36 via a bearing 48B (see FIG. 16). Therefore, the first wheel 15A and the second wheel 15B are provided rotatably on the support portion 36 around the coaxial axis O2 via the first axle 37A and the second axle 37B. In the driving wheel 120 of the embodiment, the first wheel 15A and the second wheel 15B have the same diameter.

[0053] The swivel drive unit 22 is composed of a motor. The swivel drive unit 22 is attached to the main body 10 so that an axis O9 (see Figs. 10 to 12 and 14) of the swivel drive shaft 22a extends along the vertical direction Z. A swivel drive gear 23 is fixed to the swivel drive shaft 22a. Therefore, the swivel drive gear 23 rotates about the axis O9 of the swivel drive shaft 22a by the rotational force generated by the swivel drive unit 22.

[0054] The revolving driven gear 24 is fixed to the revolving shaft 35. The revolving driven gear 24 is formed in an annular shape, and is supported together with the revolving shaft 35 so as to be rotatable relative to the main body 10 about the axis O1. The revolving driven gear 24 has meshing teeth on its annular outer surface. The meshing teeth of the revolving driven gear 24 mesh with the revolving drive gear 23. Therefore, the rotational force generated by the revolving drive unit 22 is transmitted to the revolving driven gear 24 via the revolving drive gear 23, and the revolving driven gear 24 rotates about the axis O1 together with the revolving shaft 35. In the driving wheel 110 of the embodiment, the revolving drive gear 23 and the revolving driven gear 24 are configured as spur gears.

[0055] The revolving shaft 35 is disposed so as to penetrate the first input shaft 25A coaxially with the axis O1 in the vertical direction Z, and rotatably supports the first input shaft 25A at the support portion 36 via a bearing 43b (see FIGS. 14 and 15). The first input shaft 25A is rotatably supported on the main body 10 coaxially with the axis O1 via a bearing 43a (see FIGS. 14 and 15). Therefore, the first input shaft 25A is supported so as to be rotatable relative to the revolving shaft 35 around the axis O1, and is also supported so as to be rotatable relative to the main body 10 around the axis O1. That is, the revolving shaft 35 is provided so as to be rotatable relative to the main body 10 regardless of the rotation of the first input shaft 25A. Therefore, the driving wheel 120 of the embodiment can input a rotational force to the first input shaft 25A on the axis O1, which is the axis of rotation of the wheel 15.

[0056] The revolving shaft 35 arranges the second input shaft 25B along the vertical direction Z. The second input shaft 25B is inserted through the first input shaft 25A and rotatably arranged on the outside of the first input shaft 25A via a bearing 44 (see Figs. 14 and 15). Therefore, the second input shaft 25B is supported rotatably around the axis O1 relative to the revolving shaft 35 via the first input shaft 25A, and is also supported rotatably around the axis O1 relative to the main body 10. That is, the revolving shaft 35 is provided rotatably with respect to the main body 10 regardless of the rotation of the second input shaft 25B. Therefore, the driving wheel 120 of the embodiment can input a rotational force to the second input shaft 25B on the axis O1, which is the revolving axis of the wheel 15. With this configuration, the first input shaft 25A, the second input shaft 25B, and the revolving shaft 35 are rotatably arranged coaxially along the axis O1.

[0057] The rotating shaft 35 disposes the first output shaft 40A in the vertical direction Z parallel to the axis O1 on its support portion 36, and rotatably supports it via bearings 46 (see FIG. 16). Therefore, the first output shaft 40A is supported so as to be rotatable relatively to the rotating shaft 35 about an axis O3 parallel to the axis O1.

[0058] The second output shaft 40B is disposed in the support portion 36 of the rotating shaft 35 so as to penetrate therethrough in the vertical direction Z parallel to the axis O1, and is rotatably supported via a bearing 47 (see FIG. 16). Therefore, the second output shaft 40B is supported so as to be rotatable relatively to the rotating shaft 35 about an axis O4 parallel to the axis O1.

[0059] An axis O3 of the first output shaft 40A and an axis O4 of the second output shaft 40B do not coincide in the vertical direction Z. That is, the first output shaft 40A and the second output shaft 40B are arranged on different axes. Also, the first output shaft 40A and the second output shaft 40B are arranged on different axes from the first input shaft 25A and the second input shaft 25B. In the driving wheel 120 of the embodiment, the first output shaft 40A is arranged on the lower side in the vertical direction Z, and the second output shaft 40B is arranged on the upper side in the vertical direction Z.

[0060] The driving mechanism 11 has a first driving unit 21A and a second driving unit 21B.

[0061] The first driving unit 21A is configured with a motor. The first driving unit 21A is attached to the main body 10 so that an axis O6 (see FIG. 15) of the first driving shaft 21Aa extends along the vertical direction Z.

[0062] The second driving unit 21B is composed of a motor. The second driving unit 21B is attached to the main body 10 so that the axis O7 (see FIG. 15) of the second driving shaft 21Ba extends along the width direction Y. Therefore, the axis O6 of the first driving shaft 21Aa and the axis O7 of the second driving shaft 21Ba are provided in parallel.

[0063] As shown in FIGS. 10 to 16, the transmission mechanism 13 has a first transmission mechanism 13A and a second transmission mechanism 13B.

[0064] 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 driving unit 21A to the first wheel 15A via the first input shaft 25A and the first output shaft 40A. The first transmission mechanism 13A includes a first driving gear 31A, a first driven gear 32A, a first transmission gear 38A, a first transmission output gear 39A, a first conversion gear 41A, and a first conversion output gear 42A. In the driving wheel 120 of the embodiment, the first driving gear 31A, the first driven gear 32A, the first transmission gear 38A, and the first transmission output gear 39A are configured with spur gears, and the first conversion gear 41A and the first conversion output gear 42A are configured with bevel gears.

[0065] In the first transmission mechanism 13A, the first driving gear 31A is fixed to the first driving shaft 21Aa of the first driving unit 21A as shown in FIG. 15. Therefore, the first driving gear 31A rotates around the axis O6 of the first driving shaft 21Aa by the rotational force of the first driving unit 21A. The first driven gear 32A is fixed to the upper end of the first input shaft 25A as shown in FIG. 14 and FIG. 15. Therefore, the first driven gear 32A rotates around the axis O1 of the first input shaft 25A. The first transmission gear 38A is fixed to the lower end of the first input shaft 25A as shown in FIG. 14 and FIG. 15. Therefore, the first transmission gear 38A rotates together with the first driven gear 32A around the axis O1 of the first input shaft 25A. The first transmission output gear 39A is rotatably provided on the first output shaft 40A via a bearing 46 as shown in FIG. 16. Therefore, the first transmission output gear 39A rotates around the axis O3 of the first output shaft 40A. As shown in FIG. 16, the first conversion gear 41A is integrally formed with the first transmission output gear 39A and is rotatably provided on the first output shaft 40A via a bearing 46. Therefore, the first conversion gear 41A rotates around the axis O3 of the first output shaft 40A together with the first transmission output gear 39A. The first conversion output gear 42A is integrally formed with the first wheel 15A and is rotatably provided on the first axle 37A via a bearing 48A. Therefore, the first conversion output gear 42A rotates around the axis O2 of the first axle 37A together with the first wheel 15A.

[0066] In the first transmission mechanism 13A, the first driving gear 31A meshes with the first driven gear 32A. The first transmission gear 38A meshes with the first transmission output gear 39A. The first conversion output gear 41A meshes with the first conversion output gear 42A. Therefore, the first transmission mechanism 13A transmits the rotational force of the first driving unit 21A from the first driving gear 31A to the first driven gear 32A to provide the rotational force to the first input shaft 25A, further transmits the rotational force of the first input shaft 25A from the first transmission gear 38A to the first transmission output gear 39A to provide the rotational force to the first output shaft 40A, and transmits the rotational force of the first output shaft 40A from the first conversion gear 41A to the first conversion output gear 42A to provide the rotational force to the first wheel 15A.

[0067] The second transmission mechanism 13B is also referred to as a second transmission gear mechanism. The second transmission mechanism 13B transmits the rotational force of the second driving unit 21B to the second wheel 15B via the second input shaft 25B and the second output shaft 40B. The second transmission mechanism 13B includes a second driving gear 31B, a second driven gear 32B, a second transmission gear 38B, a second transmission output gear 39B, a second conversion gear 41B, and a second conversion output gear 42B. In the driving wheel 120 of the embodiment, the second driving gear 31B, the second driven gear 32B, the second transmission gear 38B, and the second transmission output gear 39B are configured as spur gears, and the second conversion gear 41B and the second conversion output gear 42B are configured as bevel gears.

[0068] In the second transmission mechanism 13B, the second driving gear 31B is fixed to the second driving shaft 21Ba of the second driving unit 21B as shown in FIG. 15. Therefore, the second driving gear 31B rotates around the axis O7 of the second driving shaft 21Ba by the rotational force of the second driving unit 21B. The second driven gear 32B is fixed to the upper end of the second input shaft 25B as shown in FIG. 14 and FIG. 15. Therefore, the second driven gear 32B rotates around the axis O1 of the second input shaft 25B. The second transmission gear 38B is fixed to the lower end of the second input shaft 25B as shown in FIG. 14 and FIG. 15. Therefore, the second transmission gear 38B rotates together with the second driven gear 32B around the axis O1 of the second input shaft 25B. The second transmission output gear 39B is rotatably provided on the second output shaft 40B via a bearing 47 as shown in FIG. 16. Therefore, the second transmission output gear 39B rotates around the axis O4 of the second output shaft 40B. As shown in FIG. 16, the second conversion gear 41B is integrally formed with the second transmission output gear 39B and is rotatably provided on the second output shaft 40B via a bearing 47. Therefore, the second conversion gear 41B rotates around the axis O4 of the second output shaft 40B together with the second transmission output gear 39B. The second conversion output gear 42B is integrally formed with the second wheel 15B and is rotatably provided on the second axle 37B via a bearing 48B. Therefore, the second conversion output gear 42B rotates around the axis O2 of the second axle 37B together with the second wheel 15B.

[0069] In the second transmission mechanism 13B, the second driving gear 31B meshes with the second driven gear 32B. The second transmission gear 38B meshes with the second transmission output gear 39B. The second conversion gear 41B meshes with the second conversion output gear 42B. Therefore, the second transmission mechanism 13B transmits the rotational force of the second driving unit 21B from the second driving gear 31B to the second driven gear 32B to provide the rotational force to the second input shaft 25B, further transmits the rotational force of the second input shaft 25B from the second transmission gear 38B to the second transmission output gear 39B to provide the rotational force to the second output shaft 40B, and transmits the rotational force of the second output shaft 40B from the second conversion gear 41B to the second conversion output gear 42B to provide the rotational force to the second wheel 15B.

[0070] In this transmission mechanism 13, the first driving gear 31A, the first driven gear 32A, the first transmission gear 38A, the first transmission output gear 39A, the first conversion gear 41A, and the first conversion output gear 42A of the first transmission mechanism 13A and the second driving gear 31B, the second driven gear 32B, the second transmission gear 38B, the second transmission output gear 39B, the second conversion gear 41B, and the second conversion output gear 42B of the second transmission mechanism 13B have the same pitch circle diameter and number of teeth.

[0071] 11, 12 and 14, the driving wheel 120 of the embodiment is arranged such that the rotation axis O5 of the wheels 15 (first wheel 15A and second wheel 15B) is offset in a horizontal direction (front-rear direction X) perpendicular to the axis O1 of the turning shaft 35. The rotation axis O5 of the wheels intersects with the axis O2 of the axle 37, extends along the vertical direction, and is a straight line parallel to the axis O1, passing through the center between the wheels 15A and 15B (the center between the points where the wheels 15A and 15B are grounded). The configuration in which the rotation axis O5 of the wheels (first wheel 15A and second wheel 15B) is offset in a horizontal direction (front-rear direction X) perpendicular to the axis O1 of the turning shaft 35 is realized by the fact that, in the driving wheel 120 of the embodiment, the first transmission output gear 39A meshes with the first transmission gear 38A in the front-rear direction X, and This is achieved by the second transmission output gear 39B meshing with the second transmission gear 38B in the front-rear direction X.

[0072] The driving wheel 120 can rotate the wheels 15 by the driving mechanism 11. For example, by driving the first driving unit 21A and the second driving unit 21B to rotate the wheels 15A and 15B in the same direction and by making the number of rotations (rotation speeds) of the wheels 15A and 15B the same, the wheels 15A and 15B can rotate without steering. In addition, the driving wheel 120 can steer the wheels 15 by the swivel unit 12. For example, by driving the swivel driving unit 22, the wheels 15A and 15B can swivel around the axis O1 together with the swivel shaft 35 and the support unit 36 ​​relative to the main body 10, thereby steering the wheels 15A and 15B.

[0073] Here, the operation of the driving wheel 120 will be described with reference to FIG. 17. In FIG. 17, for convenience, the meshing between the first driving gear 31A and the first driven gear 32A and the meshing between the second driving gear 31B and the second driven gear 32B are shown expanded in the width direction, and the meshing between the first conversion gear 41A and the first conversion output gear 42A and the meshing between the second conversion gear 41B and the second conversion output gear 42B are shown expanded in the up-down direction. When the first input shaft 25A of the driving wheel 120 rotates in the A1 direction, the first transmission gear 38A provided on the first input shaft 25A rotates in the same direction, and the first transmission output gear 39A meshing with the first transmission gear 38A rotates in the A2 direction opposite to the A1 direction. Then, the first conversion gear 41A provided integrally with the first transmission output gear 39A rotates in the same direction. Then, the first conversion output gear 42A meshing with the first conversion gear 41A rotates in the C1 direction, causing the first wheel 15A integrally provided with the first conversion output gear 42A to rotate in the same direction. On the other hand, when the second input shaft 25B rotates in the B1 direction opposite to the A1 direction, the second transmission gear 38B provided on the second input shaft 25B rotates in the same direction, and the second transmission output gear 39B meshing with the second transmission gear 38B rotates in the B2 direction opposite to the B1 direction. Then, the second conversion gear 41B integrally provided with the second transmission output gear 39B rotates in the same direction. Then, the second conversion output gear 42B meshing with the second conversion gear 41B rotates in the C2 direction, which is the same as the C1 direction, causing the second wheel 15B integrally provided with the second conversion output gear 42B to rotate in the same direction.

[0074] At this time, the driving wheel 120 rotates the turning drive shaft 22a, so that the turning driven gear 24 meshing with the turning drive gear 23 integral with the turning drive shaft 22a rotates in the direction D. Then, the turning shaft 35 rotates in the same direction integrally with the turning driven gear 24. Then, the wheel 15 is turned and steered by the amount of the rotation.

[0075] Furthermore, when the drive wheels 120 do not drive the wheels 15, the wheels 15 can passively turn due to an external force acting from the horizontal direction. That is, the cart 100 can automatically travel and steer, and can also be manually traveled and steered by an operator.

[0076] The drive wheel 120 of the above-described embodiment is characterized by including a main body 10, a first wheel 15A and a second wheel 15B having axles 37A and 37B coaxially arranged therewith, a swivel unit 12 that supports each wheel 15A, 15B so that they can swivel relative to the main body 10, a first drive unit 21A that imparts a rotational force to the first wheel 15A, a second drive unit 21B that imparts a rotational force to the second wheel 15B, and a swivel drive unit 22 that imparts a rotational force to the swivel unit 12.

[0077] The driving wheel 120 applies a rotational force to the first wheel 15A of the twin wheels by the first driving unit 21A, applies a rotational force to the other second wheel 15B by the second driving unit 21B, and applies a rotational force to the turning unit 12 by the turning driving unit 22. Therefore, the driving wheel 120 drives the wheels 15A and 15B to travel by the first driving unit 21A and the second driving unit 21B, and drives the turning by the turning driving unit 22 separately from the travel. Therefore, according to the driving wheel 120, no turning force is generated unintentionally during travel, and straight-line stability can be ensured. And, since the driving wheel 120 drives each wheel 15A and 15B by the first driving unit 21A and the second driving unit 21B, respectively, there is no need to provide a differential gear between the wheels 15A and 15B. Moreover, since the driving wheel 120 drives the turning by the turning driving unit 22 separately from the travel, a suspension unit as in the conventional example (for example, Patent Document 1) is not required. As a result, according to the driving wheel 120 of the embodiment, it is possible to stabilize the running while suppressing the complication of the support structure for the wheels 15A, 15B.

[0078] In addition, in the embodiment of the drive wheel 120, the first drive unit 21A and the second drive unit 21B are provided on the main body 10, and include a first transmission mechanism 13A that transmits the rotational force of the first drive unit 21A to the first wheel 15A, and a second transmission mechanism 13B that transmits the rotational force of the second drive unit 21B to the second wheel 15B.

[0079] According to this drive wheel 120, by providing the first drive unit 21A and the second drive unit 21B on the main body 10, the first drive unit 21A and the second drive unit 21B are not involved in the rotation of each wheel 15A, 15B supported by the swivel unit 12, so there is no need to run power supply wiring to the first drive unit 21A and the second drive unit 21B from the swivel unit 12, which rotates relatively, to the main body 10, making it easy to handle the wiring.

[0080] In addition, in this embodiment, the drive wheels 120 have the rotational axis O5 of each wheel 15A, 15B aligned vertically and intersecting the axis O2 of the axles 37A, 37B, shifted horizontally relative to the axis O1 of the pivot shaft 35 and intersecting the axis O2 of the axles 37A, 37B.

[0081] According to the driving wheels 110, when the wheels 15A, 15B are not driven, the wheels 15A, 15B can passively turn by an external force acting from the horizontal direction. That is, the cart 100 can automatically travel and steer, and can also be manually traveled and steered by an operator.

[0082] Moreover, the bogie 100 of the embodiment includes the above-mentioned drive wheels 120 and the bogie body 101 to which the drive wheels 120 are attached. Therefore, the bogie 100 can stabilize the traveling while suppressing the complication of the support structure for the wheels 15A and 15B.

[0083] [Variations] In the above-mentioned driving wheels 110 and 120, the gears described as spur gears may be configured as helical gears, for example. Also, in the above-mentioned driving wheels 110 and 120, the gears described as bevel gears may be configured as crown gears or screw gears, for example, or may be replaced with universal joints. Also, in the above-mentioned driving wheel 110, the first wheel 15A may be directly rotated by the output shaft of the first driving unit 21A (motor), and the second wheel 15B may be directly rotated by the output shaft of the second driving unit 21B (motor) without using the transmission mechanism 13. [Explanation of symbols]

[0084] 10 Main unit 12 Swivel section 13A First transmission mechanism 13B Second transmission mechanism 15 wheels (15A first wheel, 15B second wheel) 21A First Drive Unit 21B Second drive unit 22 Swivel drive unit 100 Carts 101 Cart body 110,120 Drive wheels

Claims

1. The main body, A first wheel and a second wheel having coaxial axles; a rotating portion that supports each of the wheels rotatably relative to the main body; A first drive unit that applies a rotational force to the first wheel; A second drive unit that applies a rotational force to the second wheel; A rotation drive unit that applies a rotational force to the rotating unit; Including, Drive wheel.

2. The first drive unit and the second drive unit are provided on the rotating unit, a first transmission mechanism that transmits a rotational force of the first drive unit to the first wheel; a second transmission mechanism that transmits a rotational force of the second drive unit to the second wheel; Including, 2. The drive wheel of claim 1.

3. The first drive unit and the second drive unit are provided on the main body, a first transmission mechanism that transmits a rotational force of the first drive unit to the first wheel; a second transmission mechanism that transmits a rotational force of the second drive unit to the second wheel; Including, 2. The drive wheel of claim 1.

4. The rotation axis of each of the wheels, which is aligned in a vertical direction perpendicular to the axis of each of the axles, is shifted in a horizontal direction perpendicular to the axis of the axles with respect to the axis of the turning portion.

2. The drive wheel of claim 1.

5. Drive wheels and A carriage body to which the drive wheels are attached; Equipped with The drive wheels are The main body, A first wheel and a second wheel having coaxial axles; a rotating portion that supports each of the wheels rotatably relative to the main body; A first drive unit that applies a rotational force to the first wheel; A second drive unit that applies a rotational force to the second wheel; A rotation drive unit that applies a rotational force to the rotating unit; Including, Trolley.

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