Internal meshing planetary gear system, wheel system and vehicle

Abstract

This disclosure provides a simplified internal meshing planetary gear assembly, wheel assembly, and vehicle with easily achievable structure. The internal gear (2) has an annular gear body (22) and a plurality of pins (23) that are held in a rotatable state on the inner circumferential surface of the gear body (22) and form internal teeth (21). The planetary gear (3) has external teeth (31) that partially mesh with the internal teeth (21). The plurality of internal pins (4), when respectively inserted into a plurality of internal pin holes (32) formed in the planetary gear (3), revolve within the internal pin holes (32) and rotate relative to the gear body (22). A first bearing member (6A) rotatably supports the plurality of internal pins (4) on the gear body (22). The first bearing member (6A) has a first inner ring (61) and a first outer ring (62), and a plurality of bearing pins (63). The plurality of bearing pins (63) are held in a rotatable state between the first inner ring (61) and the first outer ring (62). For multiple pins (23) and multiple bearing pins (63), each has a different diameter and maintains a different structure.

Description

[0001] Cross Reference to Related Applications

[0002] This application is based on and claims priority to Japanese Patent Application No. 2020-146350, filed August 31, 2020, the entire contents of which are incorporated herein by reference. TECHNICAL FIELD

[0003] The present disclosure generally relates to an internal meshing planetary gear device, a wheel device, and a vehicle, and more particularly relates to an internal meshing planetary gear device in which a planetary gear having external teeth is arranged on the inside of an internal tooth gear having internal teeth, a wheel device, and a vehicle. BACKGROUND

[0004] As a related art, a so-called eccentric swing type gear device in which a planetary gear swings eccentrically while internally meshing with an internal tooth gear is known. In the gear device of the related art, an eccentric body is formed integrally with an input shaft, and a planetary gear is mounted to the eccentric body via an eccentric bearing. An external tooth such as a circular arc tooth is formed on the outer periphery of the planetary gear.

[0005] The internal tooth gear is configured by rotatably fitting a plurality of pins (roller pins) that configure the internal teeth one by one to the inner peripheral surface of a gear body (internal tooth gear body) that also serves as a housing. In the planetary gear, a plurality of internal pin holes (internal roller holes) are formed at appropriate intervals in the circumferential direction, and an internal pin and an internal roller are inserted into the internal pin holes. The internal pin is connected to a bracket at the one end side in the axial direction, and the bracket is rotatably supported to the housing via a cross roller bearing. The gear device can be used as a gear device in which the rotation corresponding to the rotational component of the planetary gear when the internal tooth gear is fixed is taken out from the bracket. SUMMARY

[0006] In the structure of the above related art, since the cross roller bearing is used as the bearing member, there is a case where the structure simplification as a whole of the internal meshing planetary gear device is hindered due to the cross roller bearing having a relatively complex structure.

[0007] An object of the present disclosure is to provide an internal meshing planetary gear device, a wheel device, and a vehicle in which structure simplification is easily achieved.

[0008] An inner meshing planetary gear device according to an aspect of the present disclosure includes an internal gear, a planetary gear, a plurality of inner pins, and a first bearing member. The internal gear has a ring-shaped gear body and a plurality of pins that are held in a self-rotatable state on an inner circumferential surface of the gear body and constitute internal teeth. The planetary gear has external teeth that partially mesh with the internal teeth. The plurality of inner pins are inserted into a plurality of inner pin holes formed in the planetary gear, respectively, and revolve in the inner pin holes and relatively rotate with respect to the gear body. The first bearing member rotatably supports the plurality of inner pins to the gear body. The first bearing member has a first inner race, a first outer race, and a plurality of bearing pins. The plurality of bearing pins are held in a self-rotatable state between the first inner race and the first outer race. The plurality of pins and the plurality of bearing pins differ in diameter and holding structure, respectively.

[0009] A wheel device according to an aspect of the present disclosure includes the inner meshing planetary gear device and a wheel body that rolls on a traveling surface by a rotational output when the plurality of inner pins relatively rotate with respect to the gear body.

[0010] A vehicle according to an aspect of the present disclosure includes the wheel device and a vehicle body that holds the wheel device.

[0011] According to an aspect of the present disclosure, an inner meshing planetary gear device, a wheel device, and a vehicle that are easy to implement and simplify the structure can be provided. BRIEF DESCRIPTION OF DRAWINGS

[0012] Figure 1A A perspective view of an outline structure of an inner meshing planetary gear device showing a basic structure is viewed from an output side of a rotation shaft.

[0013] Figure 1B A perspective view of an outline structure of the inner meshing planetary gear device described above is viewed from an input side of a rotation shaft.

[0014] Figure 2 An outline exploded perspective view of the inner meshing planetary gear device described above is viewed from an output side of a rotation shaft.

[0015] Figure 3 An outline sectional view of the inner meshing planetary gear device described above is viewed from an output side of a rotation shaft.

[0016] Figure 4 A sectional view of A1-A1 line of the inner meshing planetary gear device described above and a partial enlarged view thereof are shown. Figure 3

[0017] Figure 5 A perspective view of a structure of the inner meshing planetary gear device described above, mainly around an internal gear and a planetary gear is shown. ​

[0018] Figure 6 This is an exploded perspective view showing the structure around the internal gear and planetary gear of the aforementioned internal meshing planetary gear device.

[0019] Figure 7 This illustrates the aforementioned internal meshing planetary gear mechanism. Figure 3 Sectional view along line B1-B1 and its enlarged portion.

[0020] Figure 8 This is a perspective view showing the structure around the first bearing component of the aforementioned internal meshing planetary gear device.

[0021] Figure 9 This is an exploded perspective view showing the structure around the first bearing component of the aforementioned internal meshing planetary gear device.

[0022] Figure 10 This illustrates the aforementioned internal meshing planetary gear mechanism. Figure 3 A magnified view of region Z1.

[0023] Figure 11 This is a schematic perspective view of a wheel assembly and vehicle that uses the aforementioned internal meshing planetary gear system.

[0024] Figure 12 This is a modified example of an internal meshing planetary gear device, equivalent to... Figure 10 Enlarged image.

[0025] Figure 13 This is a schematic cross-sectional view of the internal meshing planetary gear device of Embodiment 1.

[0026] Figure 14 This illustrates the aforementioned internal meshing planetary gear mechanism. Figure 13 Sectional view along line B1-B1 and its enlarged portion.

[0027] Figure 15 This is a modified example of the internal meshing planetary gear device of embodiment 1, equivalent to Figure 10 Enlarged image.

[0028] Figure 16 This is a schematic cross-sectional view of the internal meshing planetary gear device of Embodiment 2.

[0029] Figure 17 This illustrates the aforementioned internal meshing planetary gear mechanism. Figure 16 Sectional view along line B1-B1 and its enlarged portion. Detailed Implementation

[0030] (Basic Structure)

[0031] (1) Summary

[0032] Hereinafter, regarding the outline of the internal meshing planetary gear device 1 of the present structure, reference is made to Figures 1A-4 The drawings referred to by the present disclosure are all schematic drawings, and the sizes and thicknesses of the respective structural elements in the drawings do not necessarily reflect the actual size ratios. For example, Figures 1A-4 The tooth shapes, sizes, and number of teeth of the internal teeth 21 and the external teeth 31 in FIG. 1 are only schematically shown for the purpose of explanation, and the gist is not limited to the shapes shown in the figure.

[0033] The internal meshing planetary gear device 1 (hereinafter, also simply referred to as "gear device 1") of the present structure is a gear device including an internal tooth gear 2 (refer to Figure 4 ), a planetary gear 3, and a plurality of internal pins 4. In the gear device 1, the planetary gear 3 is disposed inside the annular internal tooth gear 2, and an eccentric body bearing 5 is disposed inside the planetary gear 3. The eccentric body bearing 5 has an eccentric body inner ring 51 and an eccentric body outer ring 52, and the eccentric body inner ring 51 rotates (eccentric motion) around a rotation axis Ax1 (refer to Figure 3 ) that is offset from the center C1 (refer to Figure 3 ) of the eccentric body inner ring 51, thereby causing the planetary gear 3 to oscillate. The eccentric body inner ring 51 rotates (eccentric motion) around the rotation axis Ax1, for example, by the rotation of an eccentric shaft 54 inserted into the eccentric body inner ring 51 as shown in Figure 4 .

[0034] The internal tooth gear 2 has internal teeth 21. In particular, in the present structure, the internal tooth gear 2 has an annular gear body 22 and a plurality of pins 23. The plurality of pins 23 are held in a state of being able to rotate on the inner peripheral surface 221 of the gear body 22, and constitute the internal teeth 21. The planetary gear 3 has external teeth 31 that partially mesh with the internal teeth 21. That is, inside the internal tooth gear 2, the planetary gear 3 is inscribed in the internal tooth gear 2, and becomes a state in which a part of the external teeth 31 meshes with a part of the internal teeth 21. In this state, when the eccentric shaft 54 rotates, the planetary gear 3 oscillates, the meshing positions of the internal teeth 21 and the external teeth 31 move in the circumferential direction of the internal tooth gear 2, and a relative rotation corresponding to the difference in the number of teeth between the two gears (the internal tooth gear 2 and the planetary gear 3) occurs between the two gears. Here, if the internal tooth gear 2 is fixed, the planetary gear 3 rotates (rotates on its own axis) in conjunction with the relative rotation of the two gears. As a result, it is possible to obtain a rotational output that is reduced at a relatively high reduction ratio corresponding to the difference in the number of teeth between the two gears from the planetary gear 3.

[0035] This gear device 1 is used in such a manner that the relative rotation between the planetary gear 3 and the ring gear 2, i.e., the rotation of the planetary gear 3 corresponding to the component of self-rotation when the ring gear 2 is fixed, is extracted as the relative rotation of the rotating member with respect to the fixed member, for example. In summary, the gear device 1 rotates the rotating member by virtue of its output in a state where the fixed member is fixed. Thus, the gear device 1 functions as a gear device with a relatively high reduction ratio with the eccentric shaft 54 as the input side and the rotating member as the output side. Therefore, in the gear device 1 of the present structure, the gear body 22 is fixed in one of the fixed member and the rotating member in order to transmit the relative rotation between the planetary gear 3 and the ring gear 2 to the fixed member and the rotating member, and the planetary gear 3 is linked to the fixed member and the rotating member by the plurality of inner pins 4 in the other of the fixed member and the rotating member.

[0036] The plurality of inner pins 4 relatively rotate with respect to the ring gear 2 while orbiting within the inner pin holes 32 in a state where they are respectively inserted in the plurality of inner pin holes 32 formed in the planetary gear 3. That is, the inner pin holes 32 have a larger diameter than the inner pins 4, and the inner pins 4 are movable in such a manner as to orbit within the inner pin holes 32 in a state where they are inserted in the inner pin holes 32. Also, the wobble component of the planetary gear 3, i.e., the component of revolution of the planetary gear 3, is absorbed by the loose fitting of the inner pin holes 32 of the planetary gear 3 and the inner pins 4. In other words, the plurality of inner pins 4 respectively move in such a manner as to orbit within the plurality of inner pin holes 32, thereby absorbing the wobble component of the planetary gear 3. Therefore, the rotation (component of self-rotation) of the planetary gear 3 other than the wobble component (component of revolution) of the planetary gear 3 is transmitted to the fixed member or the rotating member by the plurality of inner pins 4.

[0037] Thus, the relative rotation between the planetary gear 3 and the ring gear 2 is transmitted to the fixed member and the rotating member as the relative rotation of the gear body 22 and the plurality of inner pins 4. Therefore, in the gear device 1, the rotation output that is reduced in speed can be extracted from either of the planetary gear 3 and the ring gear 2. That is, for example, in the case where the gear body 22 is fixed to the fixed member, the planetary gear 3 is linked to the rotating member by the plurality of inner pins 4, and thus the relative rotation between the planetary gear 3 and the ring gear 2 is extracted from the planetary gear 3. On the other hand, in the case where the gear body 22 is fixed to the rotating member, the planetary gear 3 is linked to the fixed member by the plurality of inner pins 4, and thus the relative rotation between the planetary gear 3 and the ring gear 2 is extracted from the ring gear 2.

[0038] Further, the gear device 1 includes a (first) bearing member 6. The bearing member 6 has a (first) inner ring 61 and a (first) outer ring 62. The inner ring 61 is disposed on the inner side of the outer ring 62 and is supported so as to be relatively rotatable with respect to the outer ring 62. The bearing member 6 is a component for rotatably supporting the rotating member to the fixed member. In other words, the (first) bearing member 6 is a component for rotatably supporting the plurality of inner pins 4 to the gear body 22. The gear device 1 rotatably supports the rotating member to the fixed member by such a bearing member 6, as a result of which, it is possible to output the relative rotation between the planetary gear 3 and the ring gear 2 as the rotation of the rotating member with respect to the fixed member.

[0039] However, in such a gear device 1, as a related art, there is known a technique in which a bearing member uses a cross roller bearing. In the cross roller bearing, the axes of the cylindrical rolling bodies (rollers) have a 45-degree inclination with respect to a plane orthogonal to the rotation axis Ax1, and are orthogonal to the outer periphery of the inner ring, and the axes of a pair of rolling bodies adjacent to each other in the circumferential direction of the inner ring are orthogonal to each other. That is, in the gear device 1, depending on the use thereof, various directions of load can act, like a radial load, a thrust direction (a direction along the rotation axis Ax1) load, and a bending force (bending moment load) with respect to the rotation axis Ax1. In the related art, in order to be able to withstand the above-described various directions of load, a cross roller bearing is used in the bearing member. However, in the related art, since a cross roller bearing is used as the bearing member, there is a case where the structure of the gear device 1 as a whole is hindered from being simplified due to the cross roller bearing having a relatively complicated structure. The gear device 1 of the present structure can provide an internal meshing planetary gear device 1 in which the simplification of the structure is easily achieved, by the following structure.

[0040] That is, as shown in FIGS. 1 to Figure 3 The gear device 1 of the present structure includes a ring gear 2, a planetary gear 3, a plurality of inner pins 4, a first bearing member 6, and a second bearing member 7. The ring gear 2 has a ring-shaped gear body 22, and a plurality of pins 23 held in a self-rotating state to the inner peripheral surface 221 of the gear body 22 and constituting internal teeth 21. The planetary gear 3 has external teeth 31 that partially mesh with the internal teeth 21. The plurality of inner pins 4 revolve in the inner pin holes 32 and relatively rotate with respect to the gear body 22 in a state of being respectively inserted into the plurality of inner pin holes 32 formed in the planetary gear 3. The first bearing member 6 and the second bearing member 7 support the plurality of inner pins 4 so as to be rotatable with respect to the gear body 22 at two positions in the rotation axis Ax1 direction. Here, the first bearing member 6 has a first inner ring 61, a first outer ring 62, and a plurality of bearing pins 63. Further, the plurality of inner pins 4 are located on the inner side of the second bearing member 7 when viewed from one side in the rotation axis Ax1 direction.

[0041] According to this configuration, the first bearing member 6 and the second bearing member 7 support the plurality of inner pins 4 so as to be rotatable with respect to the gear body 22 at two points in the direction of the rotation axis Ax1, and thus the plurality of inner pins 4 are supported at two points with respect to the gear body 22. Therefore, compared to a configuration in which the plurality of inner pins 4 are supported at one point with respect to the gear body 22 at one point in the direction of the rotation axis Ax1, the bending force (bending moment load) with respect to the rotation axis Ax1 is easily tolerated. Furthermore, the first bearing member 6 has a first inner ring 61, a first outer ring 62, and a plurality of bearing pins 63. That is, the first bearing member 6 is a needle bearing that uses the bearing pins 63 as "rolling elements (rollers)", and is able to tolerate a relatively large load with respect to a radial load. Moreover, while being configured to support at two points, the second bearing member 7 is positioned on the outer side of the plurality of inner pins 4 when viewed from one side in the direction of the rotation axis Ax1, and thus the limited space on the inner side of the plurality of inner pins 4 can be configured to be relatively simple. Therefore, compared to a related art configuration in which a cross roller bearing is used as a bearing member, the gear device 1 of the present configuration has the advantage that a simple configuration is easily achieved.

[0042] Furthermore, cross roller bearings are in the high-priced category among bearing members, and thus according to the configuration of the gear device 1 of the present configuration, such a cross roller bearing can be omitted, and thus the gear device 1 of the present configuration also has the advantage that low cost is easily achieved.

[0043] (2) Definitions

[0044] The "ring shape" of the present embodiment means a shape that forms a space (region) surrounded by a ring (circle) on the inner side when viewed from above, and is not limited to a circular shape (annular shape) that is a perfect circle when viewed from above, and can be, for example, an elliptical shape, a polygonal shape, or the like. Furthermore, even if the shape has a bottom, such as a cup shape, as long as the peripheral wall is a ring shape, it is included in the "ring shape".

[0045] The "loose fit" of the present embodiment means a state in which the inner pin 4 is fitted with a play (gap), and the inner pin hole 32 is a hole for the loose fit of the inner pin 4. That is, the inner pin 4 is inserted into the inner pin hole 32 in a state in which a surplus degree (gap) of space is ensured between the inner pin 4 and the inner peripheral surface 321 of the inner pin hole 32. In other words, the diameter of at least the portion of the inner pin 4 that is inserted into the inner pin hole 32 is smaller (thinner) than the diameter of the inner pin hole 32. Therefore, the inner pin 4 is able to move within the inner pin hole 32, that is, is able to relatively move with respect to the center of the inner pin hole 32, in a state in which the inner pin 4 is inserted into the inner pin hole 32. Thus, the inner pin 4 is able to revolve within the inner pin hole 32. However, it is not necessary to ensure a gap as a void between the inner peripheral surface of the inner pin hole 32 and the inner pin 4, and for example, a fluid such as a liquid can be filled into the gap.

[0046] The "revolution" in the present embodiment means that an object revolves around an axis of rotation that is not a central axis passing through the center (gravity center) of the object. When an object revolves, the center of the object moves along a revolution orbit centered on the axis of rotation. Thus, for example, in the case where an object revolves around an eccentric axis parallel to the central axis passing through the center (gravity center) of the object, the object revolves around the eccentric axis as the axis of rotation. As an example, the inner pin 4 revolves around the axis of rotation passing through the center of the inner pin hole 32, and revolves in the inner pin hole 32.

[0047] In addition, in the present embodiment, the side (right side) of the axis of rotation Ax1 is referred to as the "input side", and the other side (left side) of the axis of rotation Ax1 is referred to as the "output side". In the example of the present embodiment, the rotation is imparted to the rotating body (eccentric body inner ring 51) from the "input side" of the axis of rotation Ax1, and the relative rotation between the planetary gear 3 and the ring gear 2 is extracted from the "output side" of the axis of rotation Ax1. However, the "input side" and the "output side" are merely labels imparted for the purpose of explanation, and the gist is not to limit the positional relationship of the input and output as viewed from the gear device 1. Figure 3 Figure 3 In addition, in the present embodiment, the side (right side) of the axis of rotation Ax1 is referred to as the "input side", and the other side (left side) of the axis of rotation Ax1 is referred to as the "output side". In the example of the present embodiment, the rotation is imparted to the rotating body (eccentric body inner ring 51) from the "input side" of the axis of rotation Ax1, and the relative rotation between the planetary gear 3 and the ring gear 2 is extracted from the "output side" of the axis of rotation Ax1. However, the "input side" and the "output side" are merely labels imparted for the purpose of explanation, and the gist is not to limit the positional relationship of the input and output as viewed from the gear device 1. Figure 3

[0048] The "axis of rotation" in the present embodiment means a virtual axis (straight line) that becomes the center of the rotational motion of a rotating body. That is, the axis of rotation Ax1 is a virtual axis that does not have a physical body. The eccentric body inner ring 51 performs a rotational motion around the axis of rotation Ax1.

[0049] The "internal teeth" and the "external teeth" in the present embodiment each mean a set (group) of a plurality of "teeth" rather than a single "tooth". That is, the internal teeth 21 of the ring gear 2 are composed of a set of a plurality of teeth arranged on the inner peripheral surface 221 of the ring gear 2 (gear main body 22). Similarly, the external teeth 31 of the planetary gear 3 are composed of a set of a plurality of teeth arranged on the outer peripheral surface of the planetary gear 3.

[0050] (3) Structure

[0051] Hereinafter, the detailed structure of the internal meshing planetary gear device 1 of the present structure will be described with reference to the drawings. Figures 1A-10

[0052] The figure shows the general structure of the gear device 1, and is a perspective view as viewed from the output side (left side) of the axis of rotation Ax1. Figure 1A The figure shows the general structure of the gear device 1, and is a perspective view as viewed from the input side (right side) of the axis of rotation Ax1. Figure 3 Figure 1B Figure 3 Figure 2 ​​​​​is a schematic exploded perspective view of the gear device 1 as viewed from the output side of the rotation axis Axl. Figure 3 is a schematic sectional view of the gear device 1. Figure 4 is Figure 3 is a sectional view along the line Al-Al thereof and a partial enlarged view thereof. Figure 5 is a perspective view for mainly showing the structure around the ring gear 2 and the planetary gear 3 of the gear device 1, Figure 6 is an exploded perspective view thereof. Figure 7 is Figure 3 is a sectional view along the line Bl-Bl thereof and a partial enlarged view thereof. Figure 8 is a perspective view for mainly showing the structure around the first bearing member 6 of the gear device 1, Figure 9 is an exploded perspective view thereof. Figure 10 is Figure 3 is an enlarged view of the region Zl of Figure 4 and Figure 7 In the

[0053] (3.1) Overall Structure

[0054] As shown in Figures 1A-3 , the gear device 1 of the present structure includes the ring gear 2, the planetary gear 3, the plurality of inner pins 4, the eccentric body bearing 5, the first bearing member 6, the second bearing member 7, the eccentric shaft 54, and the support body 8. Also, in the present structure, the gear device 1 further includes the holding member 55, the counterweight 56, the first bearing 91, the second bearing 92, the spacer 93, and the housing 10. In the present structure, the material of the ring gear 2, the planetary gear 3, the plurality of inner pins 4, the eccentric body bearing 5, the first bearing member 6, the second bearing member 7, and the like, which are the constituent elements of the gear device 1, is a metal such as stainless steel, cast iron, mechanical structural carbon steel, chromium-molybdenum steel, phosphor bronze, or aluminum bronze. Also, the material of the eccentric shaft 54, the support body 8, the holding member 55, the counterweight 56, the housing 10, and the like, is the same metal as described above. The metal referred to herein includes a metal subjected to surface treatment such as nitriding treatment.

[0055] Also, in the present structure, as an example of the gear device 1, an inscribed planetary gear device using a trochoid-like tooth shape is exemplified. That is, the gear device 1 of the present structure includes an inscribed planetary gear 3 having a trochoid-like curved tooth shape.

[0056] Also, in the present structure, as an example, the gear device 1 is configured to hold the plurality of inner pins 4 by the holding member 55 (see Figure 2) fixed to a fixed member (a hub member 14 and the like described later). That is, the planetary gear 3 is linked to the fixed member with the plurality of inner pins 4, and the gear body 22 is fixed to a rotating member (the main body portion 11 and the like described later), so that the relative rotation between the planetary gear 3 and the ring gear 2 is extracted from the ring gear 2. In other words, in the present structure, when the plurality of inner pins 4 relatively rotate with respect to the gear body 22, the rotational force of the gear body 22 is extracted as an output.

[0057] Further, in the present structure, as an example, the gear device 1 is used for a wheel device Wl (refer to Figure 11 ), which will be described later in detail. In this case, the rotating member (the main body portion 11 and the like) functions as a wheel body 102 (refer to Figure 11 ), so that the wheel body 102 can be rotated in conjunction with the relative rotation between the ring gear 2 and the planetary gear 3. In this way, in the present structure, by using the gear device 1 for the wheel device Wl, the wheel body 102 can be driven in a manner that the wheel body 102 rolls on a traveling surface by the rotational output when the plurality of inner pins 4 relatively rotate with respect to the gear body 22. In summary, in the case where the gear device 1 is used as the wheel device Wl, the rotational force of the rotating member (the main body portion 11 and the like) as the wheel body 102 is extracted as an output rotational force by applying a rotational force as an input to the eccentric shaft 54. That is, the gear device 1 acts so as to take the rotation of the eccentric shaft 54 as an input rotation and take the rotation of the rotating member (the main body portion 11 and the like) to which the gear body 22 is fixed as an output rotation. Thus, in the gear device 1, with respect to the input rotation, the output rotation that is reduced at a relatively high reduction ratio is obtained as the rotation of the wheel body 102.

[0058] Further, in the gear device 1 of the present structure, as shown in Figure 3 , the rotational axis Axl on the input side and the rotational axis Axl on the output side are on the same straight line. In other words, the rotational axis Axl on the input side and the rotational axis Axl on the output side are coaxial. Here, the rotational axis Axl on the input side is the center of rotation of the eccentric shaft 54 to which the input rotation is imparted, and the rotational axis Axl on the output side is the center of rotation of the gear body 22 from which the output rotation is generated. That is, in the gear device 1, the output rotation that is reduced at a relatively high reduction ratio can be obtained with respect to the input rotation on the same axis.

[0059] As shown in Figure 1A and Figure 1B , the housing 10 is cylindrical and constitutes the outer shape of the gear device 1. In the present structure, the housing 10 functions as the wheel body 102, so that the central axis of the cylindrical housing 10 is constituted so as to coincide with the rotational axis Axl. That is, at least the outer peripheral surface of the housing 10 becomes a true circle with the rotational axis Axl as the center in a plan view (in a view from one side in the direction of the rotational axis Axl).

[0060] The housing 10 has a main body 11, a cover 12, a ring cover 13, and a hub member 14. The main body 11 is a cylindrical component with openings at both ends in the direction of the rotation axis Ax1. The cover 12 is mounted on the output side of the rotation axis Ax1 of the main body 11. Figure 3 A disc-shaped component that closes the opening on the output side of the rotation shaft Ax1 of the main body 11 on the left end face. The ring cover 13 is located on the input side of the rotation shaft Ax1 of the main body 11. Figure 3 A ring-shaped component is mounted on the end face of the right side of the main body 11. The hub component 14 is a ring-shaped component disposed inside the ring cover 13. A portion of the opening face on the input side of the rotation shaft Ax1 of the main body 11 is filled by the hub component 14. Here, the main body 11, cover 12, ring cover 13 and hub component 14 are all formed into a perfect circle centered on the rotation shaft Ax1 when viewed from above.

[0061] Multiple (eight in one example) threaded holes 111 are formed on the end face of the output side of the rotating shaft Ax1 of the main body 11 (see reference). Figure 5 Multiple threaded holes 111 are used to secure the cover 12 to the main body 11. Specifically, multiple screws 151 for securing the cover 12 pass through the cover 12 and are screwed into the threaded holes 111, thereby securing the cover 12 to the main body 11. Multiple threaded holes 112 (eight in one example) are formed around the end face of the input side of the rotation shaft Ax1 of the main body 11 (see reference). Figure 8 Multiple threaded holes 112 are used to secure the ring cap 13 to the main body 11. Specifically, multiple screws 152 for securing the ring cap 13 are passed through the ring cap 13 and screwed into the threaded holes 112, thereby securing the ring cap 13 to the main body 11.

[0062] Furthermore, the internal space of the housing 10, which is enclosed by the main body 11, cover 12, ring cover 13, and hub member 14, houses the internal gear 2, planetary gear 3, multiple inner pins 4, eccentric bearing 5, first bearing member 6, second bearing member 7, and support body 8. The hub member 14 is mounted from the input side of the rotation shaft Ax1 to a retaining member 55 that holds the multiple inner pins 4. Multiple (eight in one example) threaded holes 554 are formed on the end face of the retaining member 55 on the input side of the rotation shaft Ax1 (see reference). Figure 9 Multiple threaded holes 554 are used to secure the hub component 14 to the retaining member 55. Specifically, multiple screws 153 for securing the hub component 14 pass through the hub component 14 and are screwed into the threaded holes 554, thereby securing the hub component 14 to the retaining member 55.

[0063] Here, multiple (four in one example) fixing holes 141 are formed on the end face of the input side of the rotation shaft Ax1 of the hub component 14 (see reference).Figure 1B Multiple mounting holes 141 are used to secure the hub member 14. In this structure, since the gear device 1 is used for the wheel device W1, the hub member 14 is positioned relative to the vehicle body 100 (see reference 100) where the wheel device W1 is mounted. Figure 11 The wheel hub component 14 is fixed. Specifically, multiple screws (four in one example) for fixing pass through a part of the vehicle body 100 and are screwed into the fixing holes 141, thereby fixing the wheel hub component 14 relative to the vehicle body 100. In this way, the wheel hub component 14 is fixed to the vehicle body 100 even within the housing 10 that constitutes the wheel body 102, forming a "fixed component" that does not rotate even when the gear device 1 is driven. On the other hand, the main body 11, the cover 12, and the ring cover 13 constitute "rotating components" that rotate relative to the wheel hub component 14 when the gear device 1 is driven. That is, when the multiple inner pins 4 rotate relative to the gear body 22, the rotation of the rotating components (main body 11, cover 12, and ring cover 13) relative to the fixed component (wheel hub component 14) is taken out as an output of the gear device 1. When the housing 10 is used as the wheel body 102, these rotating components rotate and roll on the travel surface.

[0064] Therefore, the ring cover 13, which is a rotating member, and the hub member 14, which is a fixed member, are configured to rotate relative to each other about the rotation axis Ax1. Specifically, the outer diameter of the hub member 14 is smaller than the inner diameter of the ring cover 13, and a gap is generated between the hub member 14 and the ring cover 13 when the hub member 14 is disposed inside the ring cover 13.

[0065] Furthermore, the hub member 14, when viewed from above, has a through hole 142 extending through the hub member 14 along the rotation axis Ax1 at its central portion. The through hole 142 is a hole through which the eccentric shaft 54 ​​passes. The hub member 14 and the eccentric shaft 54 ​​are configured to rotate relative to each other about the rotation axis Ax1. Specifically, the inner diameter of the hub member 14 (the diameter of the through hole 142) is larger than the outer diameter of the eccentric shaft 54 ​​(its central portion 541), creating a gap between the hub member 14 and the eccentric shaft 54 ​​when the eccentric shaft 54 ​​is inserted through the through hole 142.

[0066] Furthermore, in this structure, the outer peripheral surface of the main body 11, which serves as a rotating member, becomes the contact surface, i.e., the contact surface, of the wheel body 102 that contacts the traveling surface. Therefore, a tire 103, for example made of rubber, is fitted onto the outer peripheral surface of the main body 11. Figure 1A and Figure 1B In the diagram, tire 103 is represented by an imaginary line (double-dotted line).

[0067] However, in this structure, the gear body 22 of the internal gear 2, the first outer ring 62 of the first bearing member 6, and the second outer ring 72 of the second bearing member 7 are fixed to the main body 11, which serves as a rotating member. Here, as an example, the gear body 22 and the first outer ring 62 are integrated with the main body 11. Furthermore, the main body 11 has an outer ring fixing frame 74 for fixing the second outer ring 72 (see reference). Figure 10 In particular, in this structure, the gear body 22, the first outer ring 62, and the outer ring fixing frame 74 are integrally formed from a single metal component, thus treating the gear body 22, the first outer ring 62, and the outer ring fixing frame 74 as a seamless single component (body 11). The gear body 22, the first outer ring 62, and the outer ring fixing frame 74 are arranged from the output side of the rotating shaft Ax1 in the order of gear body 22, first outer ring 62, and outer ring fixing frame 74. Therefore, as... Figure 2 As shown, the inner circumferential surface of the main body 11 includes the inner circumferential surface 221 of the gear body 22 and the inner circumferential surface 621 of the first outer ring 62.

[0068] like Figures 4-6 As shown, the internal gear 2 is an annular component with internal teeth 21. In this structure, the internal gear 2 has an annular shape, at least its inner circumferential surface being a perfect circle when viewed from above. Internal teeth 21 are formed along the circumferential direction of the annular internal gear 2 on its inner circumferential surface. All teeth constituting the internal teeth 21 are of the same shape and are evenly spaced throughout the entire circumferential region of the inner circumferential surface of the internal gear 2. That is, the pitch circle of the internal teeth 21 is a perfect circle when viewed from above. The center of the pitch circle of the internal teeth 21 is located on the rotation axis Ax1. Furthermore, the internal gear 2 has a predetermined thickness along the direction of the rotation axis Ax1. The tooth directions of the internal teeth 21 are all parallel to the rotation axis Ax1. The dimension of the internal teeth 21 in the tooth direction is slightly smaller than that in the thickness direction of the internal gear 2.

[0069] Here, as described above, the internal gear 2 has an annular (ring-shaped) gear body 22 and multiple pins 23. The multiple pins 23 are held in a rotatable state on the inner circumferential surface 221 of the gear body 22, forming the internal teeth 21. In other words, the multiple pins 23 function as multiple teeth constituting the internal teeth 21. Specifically, on the inner circumferential surface 221 of the gear body 22, as... Figure 6 As shown, multiple grooves are formed throughout the circumferential region. These multiple grooves are multiple gear-side grooves 222 that respectively serve as retaining structures for multiple pins 23 (see reference). Figure 4 In other words, the retaining structure of the multiple pins 23 includes multiple gear side grooves 222 formed on the inner circumferential surface 221 of the gear body 22. All of the multiple gear side grooves 222 are of the same shape and are equally spaced. All of the multiple gear side grooves 222 are parallel to the rotation axis Ax1 and are formed across the entire width of the gear body 22.

[0070] However, in the present structure, since the gear body 22 is a part of the main body portion 11 as described above, the plurality of gear-side grooves 222 are formed only in a portion of the main body portion 11 corresponding to the gear body 22 (see Figure 10 ). The plurality of pins 23 are fitted into the plurality of gear-side grooves 222, thereby being assembled to the gear body 22 (the main body portion 11). Each of the plurality of pins 23 is held in a state of being able to rotate within the gear-side groove 222, and is restricted in movement in the circumferential direction of the gear body 22 by the gear-side groove 222.

[0071] As shown in Figures 4-6 , the planetary gear 3 is a ring-shaped member having external teeth 31. In the present structure, the planetary gear 3 has a circular ring shape in which at least the outer peripheral surface is a true circle in plan view. On the outer peripheral surface of the circular ring-shaped planetary gear 3, the external teeth 31 are formed along the circumferential direction of the planetary gear 3. The plurality of teeth constituting the external teeth 31 are all the same shape, and are arranged at equal intervals in the entire region in the circumferential direction of the outer peripheral surface of the planetary gear 3. That is, the pitch circle of the external teeth 31 is a true circle in plan view. The center CI of the pitch circle of the external teeth 31 is located at a position deviated from the rotation axis Ax1 by a distance ΔL (see Figure 4 ). Further, the planetary gear 3 has a prescribed thickness in the direction of the rotation axis Ax1. The external teeth 31 are all formed over the entire length in the thickness direction of the planetary gear 3. The tooth direction of the external teeth 31 is all parallel to the rotation axis Ax1. In the planetary gear 3, unlike the internal tooth gear 2, the external teeth 31 and the main body of the planetary gear 3 are integrally formed from one metal member.

[0072] Here, the eccentric body bearing 5 and the eccentric shaft 54 are assembled to the planetary gear 3. That is, as shown in Figure 5 and Figure 6 , an opening portion 33 that is a circularly shaped opening is formed in the planetary gear 3. The opening portion 33 is a hole that penetrates the planetary gear 3 in the thickness direction. In plan view, the center of the opening portion 33 coincides with the center of the planetary gear 3, and the inner peripheral surface of the opening portion 33 (the inner peripheral surface of the planetary gear 3) is a concentric circle with the pitch circle of the external teeth 31. The eccentric body bearing 5 is accommodated in the opening portion 33 of the planetary gear 3. Further, the eccentric body bearing 5 and the eccentric shaft 54 are assembled to the planetary gear 3 by inserting the eccentric shaft 54 into the eccentric body inner race 51 of the eccentric body bearing 5. In the state in which the eccentric body bearing 5 and the eccentric shaft 54 are assembled to the planetary gear 3, when the eccentric shaft 54 rotates, the planetary gear 3 oscillates about the rotation axis Ax1.

[0073] The planetary gear 3, thus configured, is positioned inside the internal gear 2. Viewed from above, the planetary gear 3 is one size smaller than the internal gear 2, allowing it to oscillate inside the internal gear 2 when combined with it. External teeth 31 are formed on the outer circumferential surface of the planetary gear 3, and internal teeth 21 are formed on the inner circumferential surface of the internal gear 2. Therefore, with the planetary gear 3 positioned inside the internal gear 2, the external teeth 31 and the internal teeth 21 are opposite each other.

[0074] Furthermore, the pitch circle of the external tooth 31 is one rotation smaller than that of the internal tooth 21. Also, when the planetary gear 3 is internally tangent to the internal gear 2, the center C1 of the pitch circle of the external tooth 31 is offset by a distance ΔL (refer to the reference point) from the center of the pitch circle of the internal tooth 21 (rotation axis Ax1). Figure 4 Therefore, the external teeth 31 and the internal teeth 21 are at least partially opposed with a gap, and there is no overall meshing in the circumferential direction. However, since the planetary gear 3 oscillates (revolves) around the rotation axis Ax1 inside the internal gear 2, the external teeth 31 and the internal teeth 21 partially mesh. That is, through the oscillation of the planetary gear 3 around the rotation axis Ax1, as... Figure 4 As shown, a portion of the teeth constituting the external tooth 31 meshes with a portion of the teeth constituting the internal tooth 21. As a result, in the gear assembly 1, a portion of the external tooth 31 can mesh with a portion of the internal tooth 21.

[0075] Here, the number of teeth of the internal gear 21 in the internal gear 2 is N more than the number of teeth of the external gear 31 in the planetary gear 3 (N is a positive integer). In this structure, as an example, N is "1", so the number of teeth of the planetary gear 3 (external teeth 31) is "1" more than the number of teeth of the internal gear 2 (internal teeth 21). This difference in the number of teeth between the planetary gear 3 and the internal gear 2 defines the reduction ratio of the output rotation to the input rotation in the gear unit 1.

[0076] Furthermore, in this structure, as an example, the thickness of the planetary gear 3 is smaller than the thickness of the gear body 22 in the internal gear 2. Strictly speaking, the thickness of the planetary gear 3 is smaller than the thickness of the part of the main body 11 that functions as the gear body 22 (see reference). Figure 10 The external tooth 31 has a smaller dimension in the direction parallel to the rotation axis Ax1 than the internal tooth 21. Furthermore, the external tooth 31's dimension in the tooth direction (parallel to the rotation axis Ax1) is smaller than the internal tooth 21's dimension in the tooth direction (parallel to the rotation axis Ax1). In other words, in the direction parallel to the rotation axis Ax1, the external tooth 31 is contained within the tooth direction of the internal tooth 21.

[0077] In this structure, as described above, the relative rotation between the planetary gear 3 and the internal gear 2 is transmitted to the fixed and rotating components as a relative rotation between the gear body 22 and the plurality of internal pins 4. Figure 5 andFigure 6 As shown, the planetary gear 3 has multiple inner pin holes 32 for inserting multiple inner pins 4. The number of inner pin holes 32 is the same as the number of inner pins 4; in this structure, as an example, there are eight inner pin holes 32 and eight inner pins 4. Each inner pin hole 32 is a hole that opens in a circular shape and passes through the planetary gear 3 along its thickness direction. The multiple (here, eight) inner pin holes 32 are arranged at equal intervals along the circumferential direction on a virtual circle concentric with the opening 33.

[0078] Multiple inner pins 4 are components that connect the planetary gear 3 to a fixed member or a rotating member. In this structure, in particular, the planetary gear 3 is connected to a fixed member (hub member 14, etc.) using multiple inner pins 4, and the gear body 22 is fixed to a rotating member (body part 11, etc.). Therefore, the planetary gear 3 is directly or indirectly connected to the fixed member (hub member 14, etc.) using multiple inner pins 4. Each of the multiple inner pins 4 is cylindrical. The diameter and length of the multiple inner pins 4 are the same. The diameter of the inner pin 4 is one size smaller than the diameter of the inner pin hole 32. Thus, the inner pin 4 is inserted into the inner pin hole 32 (see reference 32) with sufficient clearance between it and the inner circumferential surface of the inner pin hole 32. Figure 4 and Figure 5 ).

[0079] The retaining member 55 is a component that retains multiple inner pins 4. In this structure, as... Figure 8 and Figure 9 As shown, the retaining member 55, viewed from above, is a perfect circle centered on the rotation axis Ax1, and is sized to the same degree as the hub member 14. The retaining member 55 has multiple retaining holes 551 into which multiple inner pins 4 are inserted. The number of retaining holes 551 is the same as the number of inner pins 4; in this structure, for example, there are eight retaining holes 551. Each retaining hole 551 is a hole that opens in a circular shape and penetrates the retaining member 55 along its thickness direction. The multiple (here, eight) retaining holes 551 are arranged at equal intervals along the circumferential direction on a virtual circle concentric with the outer periphery of the retaining member 55. The diameter of the retaining holes 551 is greater than the diameter of the inner pins 4 but smaller than the diameter of the inner pin holes 32.

[0080] In the present structure, the diameter of the holding hole 551 is substantially the same as or slightly larger than the diameter of the inner pin 4. Therefore, the movement of the inner pin 4 within the holding hole 551 is restricted, i.e., the relative movement with respect to the center of the holding hole 551 is prohibited. Thus, the inner pin 4 is held within the inner pin hole 32 in a state capable of revolving around the sun gear 2, and is held to the holding member 55 in a state incapable of revolving within the holding hole 551. Thus, the wobble component of the planetary gear 3, i.e., the revolving component of the planetary gear 3, is absorbed by the loose fit of the inner pin hole 32 and the inner pin 4, and the rotation (the self-rotation component) of the planetary gear 3 other than the wobble component (the revolving component) of the planetary gear 3 is transmitted to the holding member 55 through the plurality of inner pins 4.

[0081] Further, in the present structure, the diameter of the inner pin 4 is slightly larger than the holding hole 551, whereby the inner pin 4, in a state inserted into the holding hole 551, is capable of self-rotation within the holding hole 551 although the revolving within the holding hole 551 is prohibited. That is, the inner pin 4, in a state inserted into the holding hole 551, is not pressed into the holding hole 551, and is thus capable of self-rotation within the holding hole 551. In this way, in the gear device 1 of the present structure, the plurality of inner pins 4 are each held to the holding member 55 in a state capable of self-rotation, and thus the inner pin 4 is capable of self-rotation while revolving within the inner pin hole 32.

[0082] In summary, in the present structure, the inner pin 4 is held to the planetary gear 3 in a state capable of both revolving and self-rotating within the inner pin hole 32, and is held to the holding member 55 in a state capable of only self-rotating within the holding hole 551. That is, the plurality of inner pins 4 are each capable of revolving within the plurality of inner pin holes 32 in a state in which the self-rotation is not restricted (a state capable of self-rotation). Therefore, when the rotation (the self-rotation component) of the planetary gear 3 is transmitted to the holding member 55 by the plurality of inner pins 4, the inner pin 4 is capable of self-rotation within the holding hole 551 while revolving and self-rotating within the inner pin hole 32. Therefore, since the inner pin 4 is in a state capable of self-rotation while revolving within the inner pin hole 32, the inner pin 4 rolls with respect to the inner circumferential surface of the inner pin hole 32. In other words, the inner pin 4 rolls on the inner circumferential surface of the inner pin hole 32 while revolving within the inner pin hole 32, and thus it is difficult to generate a loss due to the frictional resistance between the inner circumferential surface of the inner pin hole 32 and the inner pin 4.

[0083] Thus, in the present configuration, since it is originally difficult to generate a loss due to frictional resistance between the inner circumferential surface of the inner pin hole 32 and the inner pin 4, the inner rollers can be omitted. Thus, in the present configuration, the plurality of inner pins 4 each adopt a configuration in which the inner pin 4 directly contacts the inner circumferential surface of the inner pin hole 32. That is, in the present configuration, the inner pin 4 in a state in which the inner roller is not assembled is inserted into the inner pin hole 32, and a configuration in which the inner pin 4 directly contacts the inner circumferential surface of the inner pin hole 32 is formed. Thus, the inner rollers can be omitted, and the diameter of the inner pin hole 32 can be suppressed to be relatively small, and thus the planetary gear 3 can be downsized (particularly, reduced in diameter), and the entire gear device 1 can also be easily downsized. As long as the size of the planetary gear 3 is constant, for example, the number (the number of pieces) of the inner pins 4 can be increased to make the transmission of rotation smooth, or the inner pins 4 can be thickened to increase the strength. Furthermore, the number of components can be suppressed to be reduced by the amount of the inner rollers, and this also contributes to the cost reduction of the gear device 1.

[0084] The holding member 55 is fixed to the hub member 14 as the fixed member. Thus, the planetary gear 3 is linked to the fixed member (the hub member 14) via the holding member 55 using the plurality of inner pins 4. Thus, since the holding member 55 is fixed to the hub member 14, the holding member 55 is also included in the "fixed member". As a result, the plurality of inner pins 4 are directly or indirectly held to the fixed member, and thus the relative position with respect to the rotation axis Ax1 is fixed. Furthermore, the opening surface of the rotation axis Ax1 on the input side in the holding hole 551 is closed by the hub member 14, for example. Thus, the movement of the inner pin 4 toward the input side of the rotation axis Ax1 is restricted by the hub member 14.

[0085] In addition, the central portion of the holding member 55 in a plan view has a bearing hole 552 that penetrates the holding member 55 in the direction of the rotation axis Ax1. The bearing hole 552 is a hole through which the eccentric shaft 54 passes, and communicates with the through hole 142 of the hub member 14. Also, the holding member 55 and the eccentric shaft 54 are configured to be able to rotate relative to each other with the rotation axis Ax1 as the center. Specifically, the inner diameter of the holding member 55 (the hole diameter of the bearing hole 552) is larger than the outer diameter of the eccentric shaft 54 (of the shaft center portion 541), and a gap is generated between the holding member 55 and the eccentric shaft 54 in a state in which the eccentric shaft 54 is inserted through the bearing hole 552.

[0086] Here, the first inner ring 61 of the first bearing member 6 and the second inner ring 71 of the second bearing member 7 are fixed to the retaining member 55. In this structure, as an example, the first inner ring 61 is integrated with the retaining member 55. Specifically, the end of the first inner ring 61 on the output side of the rotation shaft Ax1 in the retaining member 55 is in the shape of a flange protruding circumferentially from the outer peripheral surface 553 of the retaining member 55. In particular, in this structure, the retaining member 55 and the first inner ring 61 are integrally formed from a single metal member, thereby treating the retaining member 55 and the first inner ring 61 as a seamless single component.

[0087] The first bearing member 6 is a component that rotatably supports a plurality of inner pins 4 on the gear body 22. In other words, the first bearing member 6 is a component for rotatably supporting a rotating component (body part 11, etc.) on a fixed component (hub member 14, etc.).

[0088] The second bearing member 7 is a component that rotatably supports a plurality of inner pins 4 on the gear body 22. In other words, the second bearing member 7 is a component used together with the first bearing member 6 to rotatably support a rotating member (body part 11, etc.) on a fixed member (hub member 14, etc.).

[0089] The first bearing member 6 and the second bearing member 7 are arranged side by side along the rotation axis Ax1, and multiple inner pins 4 are rotatably supported on the gear body 22 at two locations along the rotation axis Ax1. In this structure, the first inner ring 61 and the second inner ring 71 are fixed to the fixed member (hub member 14, etc.), and the first outer ring 62 and the second outer ring 72 are fixed to the rotating member (body part 11, etc.). Therefore, the first bearing member 6 and the second bearing member 7 rotatably support the rotating member (body part 11, etc.) on the fixed member (hub member 14, etc.) by means of the relative rotation of the inner and outer rings. The first bearing member 6 and the second bearing member 7 will be described in more detail in the section "(3.2) Bearing Members".

[0090] like Figure 2 As shown, the eccentric shaft 54 ​​is a cylindrical component. The eccentric shaft 54 ​​has a central portion 541 and an eccentric portion 542. The central portion 541 is cylindrical, with at least its outer circumferential surface being perfectly circular when viewed from above. The center (central axis) of the central portion 541 coincides with the rotation axis Ax1. The eccentric portion 542 is disk-shaped, with at least its outer circumferential surface being perfectly circular when viewed from above. The center (central axis) of the eccentric portion 542 coincides with a center C1 offset from the rotation axis Ax1. Here, the distance ΔL between the rotation axis Ax1 and the center C1 (refer to...) Figure 2) becomes an eccentric amount of the eccentric portion 542 with respect to the shaft portion 541. The eccentric portion 542 has a flange shape that protrudes from the outer peripheral surface of the shaft portion 541 over the entire circumference at a portion other than both end portions in the length direction (axial direction) of the shaft portion 541. According to the above-described structure, for the eccentric shaft 54, the shaft portion 541 rotates (rotates on its own axis) around the rotation axis Ax1, and the eccentric portion 542 performs eccentric motion.

[0091] In the present structure, the shaft portion 541 and the eccentric portion 542 are integrally formed by one metal member, and thus a seamless eccentric shaft 54 is realized. The eccentric shaft 54 of such a shape is combined with the eccentric body bearing 5 in the planetary gear 3. Therefore, in a state in which the planetary gear 3 is combined with the eccentric body bearing 5 and the eccentric shaft 54, when the eccentric shaft 54 rotates, the planetary gear 3 swings around the rotation axis Ax1.

[0092] The eccentric body bearing 5 is a member that has the eccentric body outer ring 52 and the eccentric body inner ring 51, and that transmits only a swing component (revolution component) of the eccentric shaft 54 to the planetary gear 3, out of the rotation of the eccentric shaft 54, except for a rotation-on-its-own-axis component of the eccentric shaft 54, and that absorbs the rotation-on-its-own-axis component of the eccentric shaft 54 in the rotation of the eccentric shaft 54. Figure 4

[0093] The eccentric body outer ring 52 and the eccentric body inner ring 51 are both ring-shaped members. The eccentric body outer ring 52 and the eccentric body inner ring 51 both have a circular ring shape that is a true circle in plan view. The eccentric body inner ring 51 is smaller than the eccentric body outer ring 52 by one ring, and is disposed on the inner side of the eccentric body outer ring 52. Here, the inner diameter of the eccentric body outer ring 52 is larger than the outer diameter of the eccentric body inner ring 51, and thus a gap is generated between the inner peripheral surface of the eccentric body outer ring 52 and the outer peripheral surface of the eccentric body inner ring 51.

[0094] The plurality of rolling bodies 53 are disposed in the gap between the eccentric body outer ring 52 and the eccentric body inner ring 51. The plurality of rolling bodies 53 are disposed in parallel along the circumferential direction of the eccentric body outer ring 52. The plurality of rolling bodies 53 are all metal members of the same shape, and are disposed at equal intervals in the entire region in the circumferential direction of the eccentric body outer ring 52. In the present structure, as an example, the eccentric body bearing 5 is constituted by a deep groove ball bearing that uses a spherical body (ball) as the rolling body 53.

[0095] ​Here, the inner diameter of the inner ring 51 of the eccentric shaft 54 ​​matches the outer diameter of the eccentric portion 542 of the eccentric shaft 54. The eccentric bearing 5 is assembled with the eccentric shaft 54 ​​with the eccentric portion 542 inserted into the inner ring 51. Furthermore, the outer diameter of the outer ring 52 of the eccentric shaft 54 ​​matches the inner diameter (diameter) of the opening 33 of the planetary gear 3. The eccentric bearing 5 is assembled with the planetary gear 3 with the outer ring 52 embedded in the opening 33 of the planetary gear 3. In other words, the eccentric bearing 5, which is fitted with the eccentric portion 542 of the eccentric shaft 54, is accommodated in the opening 33 of the planetary gear 3.

[0096] Furthermore, in this structure, as an example, the width direction (parallel to the rotation axis Ax1) of the inner eccentric ring 51 and outer eccentric ring 52 of the eccentric bearing 5 is approximately the same as the thickness of the eccentric portion 542 of the eccentric shaft 54. Moreover, the width direction of the inner eccentric ring 51 and outer eccentric ring 52 is larger than the thickness of the planetary gear 3. Therefore, in the direction parallel to the rotation axis Ax1, the planetary gear 3 is contained within the area of ​​the eccentric bearing 5.

[0097] With the eccentric bearing 5 and eccentric shaft 54 ​​combined in the planetary gear 3, when the eccentric shaft 54 ​​rotates, the inner ring 51 of the eccentric bearing 5 rotates around a rotation axis Ax1 offset from the center C1 of the inner ring 51 (eccentric motion). At this time, the rotational component of the eccentric shaft 54 ​​is absorbed by the eccentric bearing 5. Therefore, through the eccentric bearing 5, the rotation of the eccentric shaft 54, except for its rotational component, is transmitted to the planetary gear 3, i.e., only the oscillating component (revolutionary component) of the eccentric shaft 54. Thus, with the planetary gear 3 combined with the eccentric bearing 5 and eccentric shaft 54, when the eccentric shaft 54 ​​rotates, the planetary gear 3 oscillates around the rotation axis Ax1.

[0098] like Figure 2 As shown, the support body 8 is a component formed in an annular shape that supports a plurality of inner pins 4. The support body 8 has an annular shape in which at least its outer circumferential surface 81 is a perfect circle when viewed from above. The support body 8 has a plurality of support holes 82 for the insertion of the plurality of inner pins 4. The number of support holes 82 is the same as the number of inner pins 4; in this structure, for example, there are eight support holes 82. Each of the plurality of support holes 82 is a hole that opens in a circular shape and penetrates the support body 8 along the thickness direction. The plurality of (here, eight) support holes 82 are arranged at equal intervals along the circumferential direction on a virtual circle concentric with the outer circumferential surface 81 of the support body 8. The diameter of the support holes 82 is greater than or equal to the diameter of the inner pins 4 but smaller than the diameter of the inner pin holes 32. In this structure, for example, the diameter of the support holes 82 is equal to the diameter of the retaining hole 551 formed in the retaining member 55. Therefore, the support body 8 supports the plurality of inner pins 4 in a state in which each of the plurality of inner pins 4 can rotate on its own. That is, each of the multiple inner pins 4 is held in a state in which it can rotate relative to either the retaining member 55 or the support body 8.

[0099] As shown in Figure 3 Fig. 8, the support body 8 is arranged so as to face the planetary gear 3 from the side (input side) of the rotation axis Axl. Also, the support body 8 functions to bundle the plurality of inner pins 4 by being inserted into the plurality of support holes 82. Thus, the support body 8 disperses the load acting on the plurality of inner pins 4 when the rotation (component of rotation) of the planetary gear 3 is transmitted to the fixed member or the rotating member.

[0100] Further, the support body 8 is positionally restricted by the plurality of pins 23 being in contact with the outer circumferential surface 81. Here, the diameter of the outer circumferential surface 81 of the support body 8 is the same as the diameter of the virtual circle (addendum circle) passing through the front end of the internal teeth 21 of the ring gear 2. Therefore, the plurality of pins 23 are all in contact with the outer circumferential surface 81 of the support body 8. Thus, in the state where the support body 8 is positionally restricted by the plurality of pins 23, the center of the support body 8 is positionally restricted so as to overlap the center of the ring gear 2 (rotation axis Axl). Thus, the center of the support body 8 is fixed, and as a result, the plurality of inner pins 4 supported by the support body 8 are also fixed by the plurality of pins 23.

[0101] Further, the plurality of pins 23 constitute the internal teeth 21 of the ring gear 2. Therefore, when the gear body 22 is rotated relative to the plurality of inner pins 4, the support body 8 supporting the plurality of inner pins 4 is rotated relative to the ring gear 2 (gear body 22) together with the plurality of inner pins 4. At this time, since the support body 8 is fixed by the plurality of pins 23, the support body 8 is smoothly rotated relative to the ring gear 2 in the state where the center of the support body 8 is maintained on the rotation axis Axl. Also, the outer circumferential surface 81 of the support body 8 is rotated relative to the gear body 22 together with the plurality of inner pins 4 in the state of being tangent to the plurality of pins 23. Therefore, if the gear body 22 of the ring gear 2 is regarded as an "outer ring" and the support body 8 is regarded as an "inner ring", the plurality of pins 23 interposed therebetween function as "rolling elements (rollers)". In this way, the support body 8 constitutes a needle bearing (needle roller bearing) together with the ring gear 2 (gear body 22 and plurality of pins 23), and smooth rotation is possible.

[0102] Further, since the support body 8 has the plurality of pins 23 interposed therebetween and the gear body 22, the support body 8 also functions as a "stopper" that suppresses the movement of the pins 23 in the direction of separation from the inner circumferential surface 221 of the gear body 22. That is, the plurality of pins 23 are interposed between the outer circumferential surface 81 of the support body 8 and the inner circumferential surface 221 of the gear body 22, thereby suppressing the lifting of the plurality of pins 23 from the inner circumferential surface 221 of the gear body 22. In summary, in the present structure, the plurality of pins 23 are each restricted in movement in the direction of separation from the gear body 22 by being in contact with the outer circumferential surface 81 of the support body 8.

[0103] Further, in the present structure, as shown inFigure 3 As shown, the support body 8 is located on the opposite side of the holding member 55 across the planetary gear 3. That is, the support body 8, the planetary gear 3, and the holding member 55 are arranged in parallel along a direction parallel to the rotation axis Ax1. Also, the support body 8 supports both end portions of the inner pin 4 in the lengthwise direction (the direction parallel to the rotation axis Ax1) together with the holding member 55, and the central portion of the inner pin 4 in the lengthwise direction is inserted through the inner pin hole 32 of the planetary gear 3. In this way, since the support body 8 and the holding member 55 support both end portions of the inner pin 4 in the lengthwise direction, it is difficult for the inner pin 4 to tilt. In particular, it is also easy to withstand the bending force (bending moment load) with respect to the rotation axis Ax1 that acts on the plurality of inner pins 4.

[0104] In addition, in the present structure, in the direction parallel to the rotation axis Ax1, the support body 8 is sandwiched between the planetary gear 3 and the housing 10 (the cover 12). Due to this, movement of the support body 8 to the output side of the rotation axis Ax1 (the left side of FIG. 1) is restricted by the housing 10. Also, for the inner pin 4 that protrudes from the support body 8 to the output side of the rotation axis Ax1 through the support hole 82 of the support body 8, movement to the output side of the rotation axis Ax1 is also restricted by the housing 10. Figure 9

[0105] The first bearing 91 and the second bearing 92 are fitted to the shaft center portion 541 of the eccentric shaft 54, respectively. Specifically, as shown, the first bearing 91 and the second bearing 92 are fitted to both sides of the eccentric portion 542 in the shaft center portion 541 in a manner sandwiching the eccentric portion 542 in the direction parallel to the rotation axis Ax1. The first bearing 91 is arranged on the output side of the rotation axis Ax1 when viewed from the eccentric portion 542. The second bearing 92 is arranged on the input side of the rotation axis Ax1 when viewed from the eccentric portion 542. In the present structure, as an example, both the first bearing 91 and the second bearing 92 are constituted by a deep groove ball bearing that uses a ball (a rolling ball) as a rolling body. Figure 3

[0106] The first bearing 91 is held to the housing 10. Specifically, a circular-shaped recess is formed on the surface of the cover 12 on the input side of the rotation axis Ax1, and the first bearing 91 is installed to the housing 10 by being embedded in this recess. On the other hand, the second bearing 92 is held to the holding member 55. Specifically, the second bearing 92 is installed to the holding member 55 by being embedded in the bearing hole 552 of the holding member 55. In other words, the second bearing 92 is fitted to the gap between the holding member 55 and the eccentric shaft 54. Due to this, the shaft center portion 541 of the eccentric shaft 54 is held in a rotatable manner at two portions on both sides of the eccentric portion 542 in the direction parallel to the rotation axis Ax1.

[0107] ​​The counterweight 56 ​​is a component through which the central portion 541 of the eccentric shaft 54 ​​is inserted. In this case, as with the gear device 1 of this structure, if the input rotation, which is on the high-speed rotation side, is accompanied by eccentric motion, vibration or the like may occur if the weight balance of the rotating body rotating at high speed is not achieved. Therefore, the counterweight is provided to achieve weight balance of the rotating body, composed of at least one of the inner ring 51 of the eccentric shaft and the component (eccentric shaft 54) that rotates together with the inner ring 51, relative to the rotation axis Ax1. The counterweight 56 ​​is formed asymmetrically with respect to the rotation axis Ax1; in this structure, for example, it is formed in a roughly fan-shaped form. Here, the counterweight 56 ​​functions by adding weight to the side of the outer ring 52 of the eccentric shaft opposite to the center C1 when viewed from the rotation axis Ax1, so that the weight balance of the eccentric shaft 54 ​​approaches evenly in the circumferential direction from the rotation axis Ax1.

[0108] The spacer 93 is a component through which the central portion 541 of the eccentric shaft 54 ​​is inserted. The spacer 93 is an annular component and is disposed between the eccentric portion 542 of the eccentric shaft 54 ​​and the first bearing 91. Thus, a certain amount of spacing of the spacer 93 is ensured between the eccentric portion 542 and the first bearing 91.

[0109] In addition, such as Figure 3 As shown, the gear assembly 1 of this structure also includes multiple oil seals 94, 95, 96, etc. Oil seal 94 is assembled between the hub member 14 and the ring cover 13, filling the gap between them. Oil seals 95 and 96, when assembled into the axial portion 541 of the eccentric shaft 54, are positioned within the through hole 142 of the hub member 14, thereby filling the gap between the hub member 14 and the eccentric shaft 54. The internal space of the housing 10 sealed by these multiple oil seals 94, 95, and 96 constitutes a sealed space.

[0110] Furthermore, a lubricant is injected into the sealed space (the internal space of the housing 10). The lubricant is a liquid and can flow within the sealed space. Therefore, when the gear device 1 is in use, for example, the lubricant enters the meshing part between the internal teeth 21, which is composed of multiple pins 23, and the external teeth 31 of the planetary gear 3. The term "liquid" as used in this disclosure includes liquid or gel-like substances. The term "gel-like" as used herein refers to a state having intermediate properties between liquid and solid, including a colloid state composed of both a liquid phase and a solid phase. For example, emulsions in which the dispersant is a liquid phase and the dispersed substance is a liquid phase, and suspensions in which the dispersed substance is a solid phase, are states referred to as gels or sols, which are included in the term "gel-like". Moreover, states in which the dispersant is a solid phase and the dispersed substance is a liquid phase are also included in the term "gel-like". In this structure, as an example, the lubricant is a liquid lubricating oil.

[0111] In the gear device 1 of the above-described structure, the eccentric shaft 54 is applied with a rotational force as an input, and the eccentric shaft 54 rotates around the rotational axis Axl, thereby the planetary gear 3 oscillates (revolves) around the rotational axis Axl. At this time, the planetary gear 3 is inscribed in the inner tooth gear 2 at the inside of the inner tooth gear 2, and oscillates in a state where a part of the external teeth 31 engages with a part of the internal teeth 21, and thus the engagement position of the internal teeth 21 and the external teeth 31 moves in the circumferential direction of the inner tooth gear 2. Thereby, a relative rotation corresponding to the difference in the number of teeth of the planetary gear 3 and the inner tooth gear 2 is generated between the two gears (the inner tooth gear 2 and the planetary gear 3). Also, since the planetary gear 3 is linked with the fixed member (the hub member 14 or the like) by the plurality of inner pins 4, and the gear body 22 is fixed to the rotating member (the main body portion 11 or the like), the relative rotation between the planetary gear 3 and the inner tooth gear 2 is extracted from the inner tooth gear 2. At this time, from the inner tooth gear 2, only the rotation corresponding to the rotation (the component of rotation) of the planetary gear 3 other than the oscillation component (the component of revolution) of the planetary gear 3 is extracted. As a result, from the rotating member on which the gear body 22 is fixed, a rotational output that is reduced at a relatively high reduction ratio corresponding to the difference in the number of teeth of the two gears can be obtained.

[0112] Also, in the gear device 1 of the present structure, as described above, the difference in the number of teeth of the inner tooth gear 2 and the planetary gear 3 defines the reduction ratio of the output rotation with respect to the input rotation in the gear device 1. That is, in a case where the number of teeth of the inner tooth gear 2 is set to "Vl" and the number of teeth of the planetary gear 3 is set to "V2", the reduction ratio Rl is represented by the following formula 1. Here, it is assumed that the gear body 22 is fixed to the rotating member and the relative rotation between the planetary gear 3 and the inner tooth gear 2 is extracted from the inner tooth gear 2.

[0113] Rl = Vl / (Vl-V2)... (Formula 1)

[0114] In summary, the smaller the difference in the number of teeth (Vl-V2) of the inner tooth gear 2 and the planetary gear 3, the larger the reduction ratio Rl. As an example, the number of teeth Vl of the inner tooth gear 2 is "30", the number of teeth V2 of the planetary gear 3 is "29", and the difference in the number of teeth (Vl-V2) is "1", and thus according to the above formula 1, the reduction ratio Rl becomes "30". In this case, when the eccentric shaft 54 rotates one revolution (360 degrees) clockwise around the rotational axis Axl from the input side of the rotational axis Axl, the gear body 22 rotates by the amount of the difference in the number of teeth "1" (i.e., about 12.0 degrees) clockwise around the rotational axis Axl.

[0115] According to the gear device 1 of the present structure, such a high reduction ratio Rl can be achieved by the combination of the one-stage gears (the inner tooth gear 2 and the planetary gear 3).

[0116] In addition, the gear device 1 only needs to include at least an internal gear 2, a planetary gear 3, multiple internal pins 4, a first bearing component 6 and a second bearing component 7, and may also include, for example, a spline bushing as a structural element.

[0117] (3.2) Bearing components

[0118] Next, the structure of the first bearing component 6 and the second bearing component 7 of this structure will be described in more detail.

[0119] like Figure 2 and Figure 3 As shown, the first bearing component 6 has a first inner ring 61 and a first outer ring 62. The first inner ring 61 and the first outer ring 62 are in a rotatable relative relationship about the rotation axis Ax1. Figure 2 and Figure 3 As shown, the first bearing component 6 has a first outer ring 62 and a first inner ring 61, as well as a plurality of bearing pins 63.

[0120] like Figures 7-9 As shown, both the first inner ring 61 and the first outer ring 62 are annular components. Both the first inner ring 61 and the first outer ring 62 are circular rings that, when viewed from above, form a perfect circle centered on the rotation axis Ax1. The first inner ring 61 is one ring smaller than the first outer ring 62 and is positioned inside the first outer ring 62. Here, since the inner diameter of the first outer ring 62 is larger than the outer diameter of the first inner ring 61, the inner circumferential surface 621 of the first outer ring 62 and the outer circumferential surface 611 of the first inner ring 61 (see reference) Figure 7 Gaps are created between them.

[0121] As described above, the first inner ring 61 is fixed to the retaining member 55. The outer peripheral surface 611 of the first inner ring 61, when viewed from above, is concentric with the outer peripheral surface 553 of the retaining member 55. In this structure, the first inner ring 61 is integral with the retaining member 55, and the flange-shaped portion protruding from the outer peripheral surface 553 of the retaining member 55 throughout its entire circumference constitutes the first inner ring 61. That is, in Figure 7 In the diagram, the portion outside the outer peripheral surface 553, represented by the imaginary line (double-dotted line), corresponds to the first inner ring 61. Since the retaining member 55 is fixed to the hub member 14, the result is that the first inner ring 61 is fixed relative to the fixing member (hub member 14, etc.).

[0122] As described above, the first outer ring 62 is fixed to the main body 11, which serves as a rotating member. The inner circumferential surface 621 of the first outer ring 62 is concentric with the outer circumferential surface 611 of the first inner ring 61 when viewed from above. In this structure, the first outer ring 62 is integral with the main body 11, and a portion of the main body 11 constitutes the first outer ring 62.

[0123] A plurality of bearing pins 63 are disposed between the first inner ring 61 and the first outer ring 62. The plurality of bearing pins 63 are arranged side-by-side along the circumferential direction of the first outer ring 62. All of the plurality of bearing pins 63 are metal components of the same shape and are equally spaced throughout the entire circumferential region of the first outer ring 62. Each of the plurality of bearing pins 63 is cylindrical. The diameter and length of the plurality of bearing pins 63 are identical.

[0124] Here, multiple bearing pins 63 are held between the first inner ring 61 and the first outer ring 62 in a rotatable state. Furthermore, the multiple bearing pins 63 are sandwiched between the outer circumferential surface 611 of the first inner ring 61 and the inner circumferential surface 621 of the first outer ring 62. Therefore, when the first outer ring 62 rotates relative to the first inner ring 61, each of the multiple bearing pins 63 rotates (self-rotates) along with the rotation of the first outer ring 62. Thus, the first bearing member 6 constitutes a needle roller bearing.

[0125] In this structure, multiple bearing pins 63 are held in a rotatable state on the inner circumferential surface 621 of the first outer ring 62. Specifically, as... Figure 9 As shown, multiple grooves are formed on the inner circumferential surface 621 of the first outer ring 62, covering the entire circumferential region. These multiple grooves are multiple bearing-side grooves 622 that respectively serve as retaining structures for multiple bearing pins 63 (see reference). Figure 7 In other words, the retaining structure of the plurality of bearing pins 63 includes a plurality of bearing side grooves 622 formed on the inner circumferential surface 621 of the first outer ring 62. All of the plurality of bearing side grooves 622 are of the same shape and are equally spaced. All of the plurality of bearing side grooves 622 are formed parallel to the rotating shaft Ax1 and extend across the entire width of the gear body 22.

[0126] However, in this structure, as described above, since the first outer ring 62 is part of the main body 11, the plurality of bearing side grooves 622 are only formed in the main body 11 at the portion corresponding to the first outer ring 62 (see reference). Figure 10 Multiple bearing pins 63 are fitted into multiple bearing side grooves 622 and thus assembled into the first outer ring 62 (main body 11). Each of the multiple bearing pins 63 is held in the bearing side groove 622 in a rotatable state and is restricted by the bearing side groove 622 to move in the circumferential direction of the first outer ring 62.

[0127] Thus, since the first bearing member 6 is a needle roller bearing, it is easy to bear the radial load primarily in the first bearing member 6. Compared with deep groove ball bearings, needle roller bearings have a larger radial load tolerance, so by equipping such a first bearing member 6, the radial load tolerance (load capacity) of the gear assembly 1 as a whole can be increased.

[0128] That is, the first bearing component 6 uses multiple bearing pins 63 with substantially the same structure as the multiple pins 23 constituting the internal teeth 21 of the internal gear 2 as rolling elements. In this structure, particularly for the bearing pins 63 and pins 23, their number and diameter are the same. That is, as Figure 4 and Figure 7 As shown, there are 30 pins 23 and 30 bearing pins 63. The diameter of pin 23 is... (Refer to Figure 4 ) and the diameter of bearing pin 63 (Refer to Figure 7 )same

[0129] Furthermore, the configuration of pins 23 and bearing pins 63 is identical when viewed from one side in the direction of the rotation axis Ax1. Therefore, pins 23 and bearing pins 63 are arranged to overlap each other in a direction parallel to the rotation axis Ax1. Specifically, the plurality of gear side grooves 222 formed on the inner circumferential surface 221 of the gear body 22, which serve as retaining structures for the plurality of pins 23, and the plurality of bearing side grooves 622 formed on the inner circumferential surface 621 of the first outer ring 62, which serve as retaining structures for the plurality of bearing pins 63, share a common configuration. That is, when both the plurality of gear side grooves 222 and the plurality of bearing side grooves 622 are formed on the gear body 22, which is part of the main body 11, or on the first outer ring 62, the configuration is identical when viewed from one side in the direction of the rotation axis Ax1 (see reference). Figure 2 Therefore, the configuration of the pin 23 held in the gear side groove 222 and the bearing pin 63 held in the bearing side groove 622 is the same when viewed from one side in the direction of the rotation axis Ax1.

[0130] However, the shapes of the gear side groove 222, which serves as the retaining structure for pin 23, and the bearing side groove 622, which serves as the retaining structure for bearing pin 63, are different. In this structure, the depth D1 of the gear side groove 222 (refer to...) Figure 4 The depth D2 of the bearing side groove 622 (refer to) Figure 7 The depths of the multiple gear side grooves 222 and the multiple bearing side grooves 622 are different (D1>D2). Specifically, when viewed from one side along the direction of the rotation axis Ax1, both the gear side grooves 222 and the bearing side grooves 622 have a diameter equal to that of the pin 23 or the bearing pin 63. The groove has an arc-shaped bottom surface with a diameter greater than the above. In other words, the bottom surfaces of both the gear side groove 222 and the bearing side groove 622 have a radius of curvature greater than or equal to the radius of the pin 23 or the bearing pin 63. Here, as an example, the bottom surfaces of both the gear side groove 222 and the bearing side groove 622 have the same radius of curvature as the pin 23 or the bearing pin 63. Furthermore, the bearing side groove 622 is made shallower than the gear side groove 222.

[0131] Furthermore, in this structure, due to the diameter of pin 23 Diameter of bearing pin 63 same Therefore, compared to the multiple gear side grooves 222, the ratio of the depth of the multiple bearing side grooves 622 to the diameter of the retaining pin is reduced. That is, the depth D2 of the bearing side groove 622 is smaller relative to the diameter of the bearing pin 63. ratio The depth D1 of the gear side groove 222 relative to the diameter of the pin 23 ratio Small. In this structure, as an example, the depth D1 of the gear side groove 222 is relative to the diameter of the pin 23. ratio It is "1 / 2". On the other hand, the depth D2 of the bearing side groove 622 is relative to the diameter of the bearing pin 63. ratio The value is "1 / 3". Here, at least the depth D2 of the bearing side groove 622 is relative to the diameter of the bearing pin 63. ratio Preferably, it is "1 / 2" or less, more preferably "1 / 3" or less, for example, it can be about "1 / 4".

[0132] In summary, the primary function of pin 23 is to exert a force in the rotational direction about the rotation axis Ax1, while the primary function of bearing pin 63 is to exert a radial force. Therefore, the bearing side groove 622 that keeps bearing pin 63 in place only needs to be at a minimum depth D2 to prevent bearing pin 63 from falling off. Conversely, by minimizing the depth D2 of the bearing side groove 622, it is advantageous to reduce the frictional resistance between the inner surface of the bearing side groove 622 and the bearing pin 63, and to reduce the loss of the first bearing component 6. Furthermore, minimizing the depth D2 of the bearing side groove 622 also allows lubricant to easily enter the bearing side groove 622.

[0133] As explained above, in this structure, pin 23 and bearing pin 63 have the same outer diameter and are configured identically when viewed from one side along the direction of rotation axis Ax1. Therefore, in this structure, the central axis Ax2 (refer to...) becomes the center of rotation (self-rotation) of pin 23. Figure 10 ) and the central axis Ax3 (refer to) which is the center of rotation (self-rotation) of bearing pin 63. Figure 10 They are located on a straight line. In other words, each of the plurality of bearing pins 63 is concentrically arranged with each of the plurality of pins 23.

[0134] Furthermore, in this structure, each of the multiple bearing pins 63 and each of the multiple pins 23 are separate units. When the rotation (self-rotation) of pin 23 and the rotation (self-rotation) of bearing pin 63 are initially asynchronous, the separate pins 23 and bearing pins 63 can rotate independently. In other words, the rotation (self-rotation) of pin 23 and the rotation (self-rotation) of bearing pin 63 are unlikely to interfere with each other or hinder each other's rotation. However, pins 23 and bearing pins 63 can rotate synchronously to some extent.

[0135] Furthermore, in this structure, the surface roughness of the outer peripheral surface 611 of the first inner ring 61 is smaller than the surface roughness of the surface adjacent to the outer peripheral surface 611 of the first inner ring 61. That is, the surface roughness of the outer peripheral surface 611 is smaller compared to the two end faces in the rotation axis Ax1 direction of the first inner ring 61. The term "surface roughness" as used in this disclosure refers to the degree of roughness of the surface of an object; the smaller the value, the less unevenness (roughness) the surface has, and the smoother it is. In this structure, as an example, the surface roughness is set to the arithmetic mean roughness (Ra). For example, through processes such as grinding, the surface roughness of the outer peripheral surface 611 of the first inner ring 61 is smaller compared to the surface other than the outer peripheral surface 611 of the first inner ring 61. In this structure, the rotation of the first outer ring 62 relative to the first inner ring 61 becomes smoother.

[0136] Furthermore, in this structure, the hardness of the outer peripheral surface 611 of the first inner ring 61 is lower than that of the peripheral surfaces of the plurality of bearing pins 63, but higher than that of the inner peripheral surface 621 of the first outer ring 62. The term "hardness" as used in this disclosure refers to the degree of hardness of an object; the hardness of a metal is, for example, expressed by the size of the indentation formed when a steel ball is pressed against it with a certain pressure. Specifically, examples of metal hardness include Rockwell hardness (HRC), Brinell hardness (HB), Vickers hardness (HV), or Shore hardness (Hs). Methods for increasing (hardening) the hardness of metal components include, for example, alloying or heat treatment. In this structure, as an example, the hardness of the outer peripheral surface 611 of the first inner ring 61 is increased by treatments such as carburizing and quenching. In this structure, even due to the rotation of the first outer ring 62 relative to the first inner ring 61, wear particles are unlikely to be generated, and the smooth rotation of the first bearing member 6 can be maintained for a long time.

[0137] Such a surface structure with low surface roughness and high hardness is also preferably suitable for the outer peripheral surface 81 of the support body 8. That is, in this structure, the support body 8 functions as the "inner ring" of the same needle roller bearing as the first bearing member 6, so an appropriate surface roughness and hardness are preferably also suitable for the outer peripheral surface 81 of the support body 8, which is equivalent to the outer peripheral surface of the inner ring.

[0138] like Figure 2 and Figure 3As shown, the second bearing component 7 has a second outer ring 72 and a second inner ring 71. The second inner ring 71 and the second outer ring 72 are in a rotatable relative relationship about the rotation axis Ax1. Figure 2 and Figure 3 As shown, the second bearing component 7 has a second outer ring 72 and a second inner ring 71, as well as a plurality of second rolling elements 73.

[0139] like Figure 2 As shown, both the second inner ring 71 and the second outer ring 72 are annular components. Both the second inner ring 71 and the second outer ring 72 are circular rings that, when viewed from above, form a perfect circle centered on the rotation axis Ax1. The second inner ring 71 is one ring smaller than the second outer ring 72 and is positioned inside the second outer ring 72. Here, since the inner diameter of the second outer ring 72 is larger than the outer diameter of the second inner ring 71, a gap is created between the inner circumferential surface of the second outer ring 72 and the outer circumferential surface of the second inner ring 71. Furthermore, in this structure, as... Figure 3 As shown, the inner diameter of the second outer ring 72 is larger than the outer diameter of the first inner ring 61 but smaller than the inner diameter of the first outer ring 62. The outer diameter of the second inner ring 71 is smaller than the outer diameter of the first inner ring 61.

[0140] The second inner ring 71 is fixed to the retaining member 55. Here, the inner diameter of the second inner ring 71 matches the outer diameter of the retaining member 55 (outer peripheral surface 553). The second bearing member 7 is combined with the retaining member 55 with the retaining member 55 inserted into the second inner ring 71. Since the retaining member 55 is fixed to the hub member 14, the second inner ring 71 is fixed relative to the fixed member (hub member 14, etc.).

[0141] The second outer ring 72 is fixed to the main body 11, which serves as a rotating member. The outer diameter of the second outer ring 72 is related to the outer ring fixing frame 74 in the main body 11 (see reference). Figure 3 The inner diameters of the bearing components are the same. The second bearing component 7 is combined with the main body 11 in a state where the second outer ring 72 is embedded in the outer ring fixing frame 74 of the main body 11. In other words, the second bearing component 7, which is a rotating component, is housed in the outer ring fixing frame 74 of the main body 11, in a state where it is assembled with the retaining component 55.

[0142] A plurality of second rolling elements 73 are disposed in the gap between the second inner ring 71 and the second outer ring 72. The plurality of second rolling elements 73 are arranged side-by-side along the circumferential direction of the second outer ring 72. All of the plurality of second rolling elements 73 are metal components of the same shape and are evenly spaced throughout the entire circumferential region of the second outer ring 72. In this structure, as an example, the second bearing member 7 is constructed of a deep groove ball bearing using balls as the second rolling elements 73. That is, the second bearing member 7 comprises a deep groove ball bearing.

[0143] Thus, since the second bearing member 7 is a deep groove ball bearing, it is easy for the second bearing member 7 to primarily bear the load in the thrust direction (along the direction of the rotation axis Ax1). That is, the second bearing member 7 bears at least the load in the direction of the rotation axis Ax1. Although the radial load tolerance of a deep groove ball bearing is smaller than that of a needle roller bearing, the thrust load tolerance is larger. Therefore, by equipping such a second bearing member 7, the thrust load tolerance (load capacity) of the gear device 1 as a whole can be increased.

[0144] In summary, the gear assembly 1 of this structure, including the first bearing member 6 and the second bearing member 7, can easily withstand radial loads and thrust loads. Specifically, the gear assembly 1 can withstand radial loads via the first bearing member 6, which is a needle roller bearing, and thrust loads via the second bearing member 7, which is a deep groove ball bearing. Furthermore, the gear assembly 1, through the first bearing member 6 and the second bearing member 7, rotatably supports multiple inner pins 4 on the gear body 22 at two locations along the rotation axis Ax1. Therefore, the gear assembly 1 can easily withstand any bending force (bending moment load) on the rotation axis Ax1.

[0145] Thus, in this gear assembly 1, even without using crossed roller bearings, it can withstand three types of loads: radial load, thrust load, and bending force on the rotating shaft Ax1, ensuring the required rigidity. Moreover, by sharing the load between the first bearing member 6 and the second bearing member 7, it also helps to extend the lifespan of each of the first bearing member 6 and the second bearing member 7.

[0146] Next, refer to Figure 3 and Figure 10 This describes the relative positional relationship between the first bearing member 6 and the second bearing member 7, and their arrangement. Specifically, in this structure, the first bearing member 6 and the second bearing member 7 rotatably support multiple inner pins 4 on the gear body 22 at two locations along the rotation axis Ax1. Therefore, the first bearing member 6 and the second bearing member 7 are arranged side-by-side along a direction parallel to the rotation axis Ax1.

[0147] In this structure, such as Figure 3As shown, the internal gear 2, the first bearing member 6, and the second bearing member 7 are arranged side-by-side from the output side of the rotating shaft Ax1 in the order of internal gear 2, first bearing member 6, and second bearing member 7. That is, the first bearing member 6 is located between the internal gear 2 and the second bearing member 7 in a direction parallel to the rotating shaft Ax1. In other words, the first bearing member 6 and the second bearing member 7 are located on the same side in the direction of the rotating shaft Ax1 with respect to the plurality of pins 23. In this structure, both the first bearing member 6 and the second bearing member 7 are located on the input side of the rotating shaft Ax1 with respect to the plurality of pins 23. Figure 3 (Right side).

[0148] Furthermore, in the direction of rotation axis Ax1, a plurality of bearing pins 63 are located between the second bearing member 7 and the plurality of pins 23. That is, the first bearing member 6 is located on the input side of rotation axis Ax1 relative to the plurality of pins 23. Figure 3 (on the right side), the second bearing member 7 is located on the input side of the rotation shaft Ax1 relative to the first bearing member 6. Figure 3 (to the right). Therefore, in a direction parallel to the rotation axis Ax1, a plurality of bearing pins 63 of the first bearing member 6 are sandwiched between the second bearing member 7 and a plurality of pins 23.

[0149] Here, the internal gear 2, the first bearing component 6, and the second bearing component 7 are arranged side by side with approximately no gap in a direction parallel to the rotation axis Ax1. Specifically, as... Figure 10 As shown, when the main body 11 is divided into three regions in a direction parallel to the rotation axis Ax1, these three regions function as the internal gear 2, the first outer ring 62 of the first bearing member 6, and the outer ring fixing frame 74 for fixing the second bearing member 7, respectively. That is, in this structure, the gear body 22, the first outer ring 62, and the outer ring fixing frame 74 constitute a seamless component (main body 11), therefore, in Figure 10 In the diagram, the gear body 22, the first outer ring 62, and the outer ring fixing frame 74 are distinguished by the boundary lines represented by imaginary lines (double-dotted lines).

[0150] With the configuration described above, one end of the plurality of bearing pins 63 in the direction of rotation axis Ax1 contacts the second outer ring 72 or the second inner ring 71. Specifically, as Figure 10 As shown, the input side of the rotating shaft Ax1 of bearing pin 63 ( Figure 10 The right end face of the bearing pin 63 contacts the second outer ring 72 of the second bearing member 7. Therefore, the movement of the bearing pin 63 toward the input side of the rotation shaft Ax1 is restricted by the second outer ring 72. Furthermore, the other ends of the plurality of bearing pins 63 in the direction of the rotation shaft Ax1 contact the pin 23. Specifically, as... Figure 10 As shown, the output side of the rotating shaft Ax1 of bearing pin 63 ( Figure 10The left end face of the bearing pin 63 contacts the pin 23. Therefore, the movement of the bearing pin 63 toward the output side of the rotating shaft Ax1 is restricted by the pin 23.

[0151] Furthermore, in the gear assembly 1 of this structure, at least a portion of each of the plurality of inner pins 4 is positioned on the axial side (rotation axis Ax1 direction) of the first bearing member 6 at the same position as the first bearing member 6 and the second bearing member 7. That is, as shown... Figure 10 As shown, in a direction parallel to the rotation axis Ax1, the inner pin 4 positions at least a portion of itself in the same position as the first bearing member 6 and the second bearing member 7.

[0152] In other words, each of the plurality of inner pins 4 is at least partially disposed inside the first bearing member 6 and the second bearing member 7. In summary, in this structure, as described above, when viewed from the side along the rotation axis Ax1, the plurality of inner pins 4 are located inside the second bearing member 7. Furthermore, in relation to the first bearing member 6, when viewed from the side along the rotation axis Ax1, the plurality of inner pins 4 are also located inside the first bearing member 6. Thus, with at least a portion of each of the plurality of inner pins 4 arranged axially in the same position as the first bearing member 6 and the second bearing member 7, the size of the gear assembly 1 in the direction parallel to the rotation axis Ax1 can be minimized.

[0153] Furthermore, the first bearing member 6 and the second bearing member 7 are positioned relative to the retaining member 55 that holds the plurality of inner pins 4 as follows: When viewed from the direction of rotation axis Ax1, the first bearing member 6 and the second bearing member 7 are located outside the retaining member 55. Specifically, the first inner ring 61 of the first bearing member 6, being a flange shape that protrudes circumferentially from the outer peripheral surface 553 of the retaining member 55, is located outside the retaining member 55 when viewed from the direction of rotation axis Ax1. The second bearing member 7, being combined with the retaining member 55 in a state where the retaining member 55 is inserted into the second inner ring 71, is also located outside the retaining member 55 when viewed from the direction of rotation axis Ax1.

[0154] (4) Applicable examples

[0155] Next, refer to Figure 11 This section describes an applicable example of the gear device 1 of this structure.

[0156] The gear assembly 1 and the wheel body 102 together constitute the wheel assembly W1. In other words, the wheel assembly W1 of this structure includes the gear assembly 1 and the wheel body 102. The wheel body 102 rolls on the travel surface through the rotational output when the multiple inner pins 4 rotate relative to the gear body 22. In this structure, the main body 11, cover 12, and ring cover 13, which are "rotating members" in the housing 10 that constitutes the outer contour of the gear assembly 1, constitute the wheel body 102. That is, in the wheel assembly W1 of this structure, the gear assembly 1 rotates as input rotation of the eccentric shaft 54 ​​and rotates as output rotation of the rotating member (main body 11, etc.) to which the gear body 22 is fixed, thereby rotating the wheel body 102 and rolling on the travel surface. Here, a tire 103, for example made of rubber, is fitted on the outer peripheral surface of the main body 11, which is the contact surface of the wheel body 102 that contacts the travel surface, i.e., the contact surface.

[0157] And, for example Figure 11 As shown, the wheel assembly W1, which uses the gear device 1, together with the vehicle body 100 constitutes the vehicle V1. In other words, the vehicle V1 of this structure includes the wheel assembly W1 and the vehicle body 100. The vehicle body 100 holds the wheel assembly W1. That is, the vehicle V1 of this structure uses the wheel assembly W1, which includes the gear device 1, as wheels, and the wheel body 102 rotates and rolls on the travel surface, thereby traveling on a flat travel surface formed by the floor surface, etc. Figure 11 In the example, vehicle V1 includes four wheel assemblies W1, which are respectively mounted at the four corners of a rectangular body 100 viewed from above. Such a vehicle V1 includes a drive source 101 for imparting driving force to the wheel assemblies W1. Figure 11 In the example, the vehicle V1 is equipped with four drive sources 101, which are arranged as "hub motors" that correspond one-to-one with the wheel assembly W1.

[0158] The drive source 101 generates a driving force to oscillate the planetary gears 3 of the gear assembly 1 included in each wheel assembly W1. Specifically, the drive source 101 is a power source such as a motor (electric motor). The power generated by the drive source 101 is transmitted to the eccentric shaft 54 ​​in the gear assembly 1. That is, the drive source 101 causes the planetary gears 3 to oscillate by rotating the eccentric shaft 54 ​​of the corresponding wheel assembly W1 around the rotation axis Ax1. As a result, the rotation (input rotation) generated by the drive source 101 is reduced in the gear assembly 1 with a relatively high reduction ratio, and the wheel body 102 is rotated with a relatively high torque.

[0159] In this way, by individually driving multiple (four in this case) wheel assemblies W1, the vehicle V1 can move in any direction on the travel surface. For example, the vehicle V1 can travel in a straight line by driving multiple wheel assemblies W1 to rotate in the same direction at the same speed, and by imparting a rotational difference between the multiple wheel assemblies W1, it can change its direction of travel to perform cornering or turning. Therefore, the vehicle V1 can perform forward, reverse, and left / right turning. The turning mentioned here includes in-situ turning and turning on the spot.

[0160] In this way, vehicle V1, using wheel assembly W1 as its drive wheels, can move freely on the travel surface under the control of drive source 101. In particular, vehicle V1 with this structure is suitable for vehicles requiring relatively high torque, such as Automated Guided Vehicles (AGVs). This AGV, acting as an automated guided vehicle, autonomously moves on the travel surface, for example, with the transported goods loaded on its body 100. Thus, vehicle V1 can transport the transported goods placed in one location to another.

[0161] In this vehicle V1, the wheel assembly W1 needs to support not only the weight of the vehicle body 100, but also the weight of the cargo loaded on the vehicle body 100. That is, not only when the vehicle V1 is moving, but also when the vehicle V1 is stopped, there are sometimes situations where a relatively large load acts on the wheel assembly W1 in the radial direction (orthogonal to the rotation axis Ax1). The wheel assembly W1 of this structure uses a needle roller bearing with a bearing pin 63 as the "rolling element (roller)" as the first bearing member 6 of the gear assembly 1, so it can withstand a relatively large load for radial loads.

[0162] Furthermore, when vehicle V1 travels on curves or turns, a thrust load (along the direction of the rotation axis Ax1) also acts on the wheel assembly W1, but this thrust load is much smaller than the radial load. Moreover, since the wheel assembly W1 of this structure uses a deep groove ball bearing as the second bearing member 7 of the gear assembly 1, this thrust load can be borne by the second bearing member 7. In summary, the wheel assembly W1 using the gear assembly 1 of this structure is particularly suitable for vehicles like unmanned transport vehicles (UAVs) that are prone to experiencing relatively large radial loads but not such large thrust loads.

[0163] Furthermore, in this structure, since the gear assembly 1 extracts the rotational force of the gear body 22 as its output, when the wheel assembly W1 is driven, the first outer ring 62, which is integrated with the gear body 22, also rotates around the rotation axis Ax1. When the first outer ring 62 rotates, the multiple bearing pins 63 held by the multiple bearing side grooves 622 of the first outer ring 62 also rotate around the rotation axis Ax1. As a result, in the first bearing member 6, which mainly bears radial loads, the bearing pins 63 located in the vertical direction of the rotation axis Ax1 change constantly, thus easily avoiding the situation where a portion of the bearing pins 63 are concentrated under load.

[0164] Furthermore, in this structure, the drive source 101 is not included as a component of the wheel assembly W1, but this is not a limitation; the drive source 101 may also be included as a component of the wheel assembly W1. In this case, the wheel assembly W1 includes the drive source 101, the gear assembly 1, and the wheel body 102.

[0165] (5) Variations

[0166] The basic structure is merely one of the various structures disclosed herein. Various modifications can be made to the basic structure, depending on the design, as long as the purpose of this disclosure is achieved. Furthermore, the accompanying drawings referenced in this disclosure are schematic diagrams, and the size and thickness ratios of the constituent elements shown may not reflect actual dimensional ratios. The following are examples of variations of the basic structure. These variations can be appropriately combined and applied.

[0167] In the basic structure, a gear device 1 with a single planetary gear 3 is illustrated; however, the gear device 1 may include multiple planetary gears 3. For example, if the gear device 1 includes two planetary gears 3, it is preferable that these two planetary gears 3 are arranged with a 180-degree phase difference around the rotation axis Ax1. Alternatively, if the gear device 1 includes three planetary gears 3, it is preferable that these three planetary gears 3 are arranged with a 120-degree phase difference around the rotation axis Ax1. In this way, with the multiple planetary gears 3 evenly arranged circumferentially around the rotation axis Ax1, weight balance among the multiple planetary gears 3 can be achieved.

[0168] Furthermore, the tooth profile and other structural (principles) can be appropriately modified. The gear device 1 can be, for example, an eccentric oscillating type gear device employing a planetary gear 3 with a circular tooth profile (see, for example, Japanese Patent Application Publication No. 2017-137989). Additionally, the gear device 1 can be, for example, an eccentric oscillating type gear device that converts the rotation of the input gear into eccentric oscillation via a spur gear and crankshaft (see, for example, Japanese Patent Application Publication No. 2020-85213).

[0169] In addition, such as Figure 12As shown, each of the plurality of bearing pins 63 can be integrally formed with each of the plurality of pins 23. That is, in Figure 12 In the example, a pin is extended axially, with one part functioning as bearing pin 63 and the other part functioning as pin 23. In this modified structure, pin 23 rotates together with bearing pin 63 and cannot rotate independently, but this reduces the number of components.

[0170] Furthermore, each of the plurality of inner pins 4 is configured, at least a portion thereof, in the direction of the rotation axis Ax1 at the same position as the first bearing member 6 or the second bearing member 7, which is not a necessary configuration in the gear device 1. That is, each of the plurality of inner pins 4 is arranged side by side (opposite to) the first bearing member 6 or the second bearing member 7 in the direction of the rotation axis Ax1.

[0171] Furthermore, the number of internal pins 4, the number of pins 23 (the number of teeth of internal teeth 21), and the number of teeth of external teeth 31 described in the basic structure are just examples and can be changed appropriately.

[0172] Furthermore, the second bearing component 7 is not limited to a deep groove ball bearing; for example, it can be a crossed roller bearing or an angular contact ball bearing. In addition, the second bearing component 7 can be a structure that can withstand radial loads, thrust loads (in the direction along the rotation axis Ax1), and bending forces (bending moment loads) on the rotation axis Ax1, such as a four-point contact ball bearing.

[0173] In addition, the gear assembly 1 may also include bearing components such as deep groove ball bearings, crossed roller bearings, or angular contact ball bearings, in addition to the second bearing component 7.

[0174] Furthermore, the eccentric bearing 5 is not limited to deep groove ball bearings; for example, it can be an angular contact ball bearing. Moreover, the eccentric bearing 5 is not limited to ball bearings; for example, it can be a roller bearing such as a cylindrical roller bearing, a needle roller bearing, or a tapered roller bearing, where the rolling elements 53 are composed of non-spherical "rollers".

[0175] Furthermore, the materials of the various structural elements of the gear device 1 are not limited to metal; for example, they can be resins such as engineering plastics.

[0176] Furthermore, the gear device 1 is not limited to a structure that extracts the rotational force of the gear body 22 as an output when the multiple inner pins 4 rotate relative to the gear body 22. For example, the planetary gear 3 can be connected to a rotating member by multiple inner pins 4, and the gear body 22 can be fixed to a fixed member, thereby extracting the rotational force (rotation component) of the planetary gear 3 as an output when the multiple inner pins 4 rotate relative to the gear body 22.

[0177] In addition, lubricants are not limited to liquid substances such as lubricating oil (oil), but can also be gel-like substances such as lubricating grease.

[0178] Additionally, the gear assembly 1 may include internal rollers. That is, in the gear assembly 1, it is not necessary for each of the multiple internal pins 4 to be in direct contact with the inner circumferential surface 321 of the internal pin hole 32; internal rollers may be sandwiched between each of the multiple internal pins 4 and the internal pin hole 32. In this case, the internal rollers are mounted on the internal pins 4 and can rotate about the internal pins 4 as an axis. Furthermore, it is not necessary for each of the multiple internal pins 4 to be held in a rotating state in the retaining member 55.

[0179] Furthermore, each of the plurality of inner pins 4 may be configured in the same position as the first bearing member 6 or the second bearing member 7 in the direction of rotation axis Ax1, provided that at least a portion of each inner pin 4 is disposed within the range of the first bearing member 6 or the second bearing member 7 in the direction of rotation axis Ax1.

[0180] Furthermore, it is not necessary in the gear assembly 1 for multiple inner pins 4 to connect the planetary gear 3 to the fixed member (hub member 14, etc.) via the retaining member 55. For example, multiple inner pins 4 can be inserted into the retaining holes formed in the hub member 14, thereby directly connecting the planetary gear 3 to the fixed member (hub member 14, etc.).

[0181] Furthermore, the positioning of multiple inner pins 4 relative to the support body 8 in both the circumferential and radial directions is not necessary in the gear device 1. For example, the support body 8 may have a slit-like support hole 82 extending radially, with the multiple inner pins 4 positioned relative to the support body 8 only in the circumferential direction. Conversely, the support body 8 may also have multiple inner pins 4 positioned relative to the support body 8 only in the radial direction.

[0182] Furthermore, the inclusion of the counterweight 56, as in the basic structure, is not essential for the gear mechanism 1. That is, the counterweight 56 ​​can be omitted, and weight reduction can be achieved by reducing the weight of a portion of the rotating body (such as the inner ring 51 of the eccentric inner ring and the eccentric shaft 54), thereby achieving weight balance of the rotating body relative to the rotating shaft Ax1. With this structure, the number of components can be reduced, and suppression of vibrations caused by the weight balance of the high-speed rotating body can also be expected.

[0183] Furthermore, vehicle V1 only needs to include one or more wheel assemblies W1, and the number of wheel assemblies W1 is not limited to four (four wheels). For example, vehicle V1 may include one to three wheel assemblies W1, or it may include five or more wheel assemblies W1. Moreover, the drive source 101 for driving the wheel assemblies W1 is not limited to a one-to-one arrangement of hub motors relative to each wheel assembly W1; one drive source 101 can be provided for multiple wheel assemblies W1. Furthermore, the wheel assemblies W1 in the basic structure only need to be provided on the drive wheels of vehicle V1; for example, in addition to the wheel assemblies W1 that serve as drive wheels, vehicle V1 may also include one or more driven wheels. Driven wheels are "non-drive wheels" that do not receive power from the drive source 101 and therefore do not generate the driving force for the movement of vehicle V1.

[0184] Furthermore, the vehicle V1 using the wheel device W1, which includes the gear device 1 with a basic structure, is not limited to an automated guided vehicle (AGV). For example, it can also be a monitoring vehicle or a camera vehicle, or a vehicle other than a transport vehicle. In addition, the vehicle V1 is not limited to an autonomous vehicle that is not driven by anyone. For example, it can also be a vehicle that a person rides in and operates (drives), or a vehicle that a person remotely operates.

[0185] Furthermore, the gear assembly 1 of the basic structure is not limited to its use as a wheel assembly W1, but can also be applied to robots such as horizontal articulated robots, i.e., SCARA (Selective Compliance Assembly Robot Arm) type robots. In this case, the gear assembly 1, together with the drive source 101 that generates the driving force for the planetary gear 3 to swing, constitutes an actuator, which is mounted on the robot. Moreover, the applicability of the gear assembly 1 and the actuator is not limited to horizontal articulated robots; for example, it can be industrial robots other than horizontal articulated robots, or robots other than industrial robots. Among industrial robots other than horizontal articulated robots, examples include vertical articulated robots or parallel link robots. Among robots other than industrial robots, examples include home robots, nursing robots, or medical robots.

[0186] Furthermore, the integrated structure of the gear body 22, the first outer ring 62, and the outer ring fixing frame 74, as in the basic structure, is not necessary for the gear device 1. For example, the gear body 22, the first outer ring 62, and the outer ring fixing frame 74 can be separate (individual components), and the gear body 22, the first outer ring 62, and the outer ring fixing frame 74 can be fixed to the main body 11 by pressing, welding, or bonding.

[0187] Furthermore, the integration of the first inner ring 61 with the retaining member 55, as in the basic structure, is not necessary for the gear device 1. For example, the first inner ring 61 and the retaining member 55 can be separate (individual components), with the first inner ring 61 fixed to the retaining member 55 by means of pressing, welding, or bonding. In addition, the second inner ring 71 can be integrated with the retaining member 55.

[0188] (Implementation Method 1)

[0189] The internal meshing planetary gear device 1A (hereinafter also simply referred to as "gear device 1A") of this embodiment is as follows: Figure 13 and Figure 14 As shown, the structure of the first bearing component 6A differs from that of the gear assembly 1 in the basic structure. Hereinafter, for structures identical to the basic structure, the same reference numerals will be used, and descriptions will be omitted where appropriate. Figure 13 This is a schematic cross-sectional view of gear assembly 1A. Figure 14 yes Figure 13 The sectional view along line B1-B1 and its enlarged partial view. However, in Figure 14 In the middle, for components other than the eccentric shaft 54, although they are cross-sections, the section lines are omitted.

[0190] However, in the aforementioned related technologies, crossed roller bearings are used as bearing components, which can hinder the simplification of the overall structure of the gear device 1 due to the relatively complex structure of the crossed roller bearings. The gear device 1A of this embodiment provides an internal meshing planetary gear device 1A with a simplified structure that is easy to achieve through the following structure.

[0191] That is, such as Figure 13 and Figure 14 As shown, the gear device 1A of this embodiment includes an internal gear 2, a planetary gear 3, a plurality of inner pins 4, and a first bearing member 6A. The internal gear 2 has an annular gear body 22 and a plurality of pins 23 that are held in a rotatable state on the inner circumferential surface 221 of the gear body 22 and form internal teeth 21. The planetary gear 3 has external teeth 31 that partially mesh with the internal teeth 21. The plurality of inner pins 4, when respectively inserted into a plurality of inner pin holes 32 formed in the planetary gear 3, revolve within the inner pin holes 32 and rotate relative to the gear body 22. The first bearing member 6A has a first inner ring 61 and a first outer ring 62, and a plurality of bearing pins 63. The plurality of bearing pins 63 are held in a rotatable state between the first inner ring 61 and the first outer ring 62. Here, the plurality of pins 23 and the plurality of bearing pins 63 have different diameters and different holding structures.

[0192] According to this configuration, the first bearing member 6A has a first inner ring 61, a first outer ring 62, and a plurality of bearing pins 63. That is, the first bearing member 6A is a needle roller bearing with the bearing pins 63 as "rolling elements (rollers)," capable of withstanding relatively large radial loads. Furthermore, since the diameters and retaining structures of the plurality of pins 23 and the plurality of bearing pins 63 are different, the diameters and retaining structures of the bearing pins 63 are designed to easily withstand various envisioned loads. Therefore, compared to related technologies using crossed roller bearings as bearing members, the gear device 1A of this embodiment has the advantage of easily achieving structural simplification.

[0193] That is, the diameters of the plurality of pins 23 and the plurality of bearing pins 63 are different. In this embodiment, compared with the basic structure, the diameters of the bearing pins 63 in the first bearing member 6A are different. (Refer to Figure 14 The ratio relative to length increases. That is, in this embodiment, a coarse pin is used as the bearing pin 63. Therefore, as Figure 13 As shown, bearing pin 63 has a larger diameter than pin 23. In other words, the diameter of bearing pin 63 is... Diameter of pin 23 (Refer to Figure 4 Therefore, in the first bearing member 6A of this embodiment, compared with the first bearing member 6 of the basic structure, the radial load-bearing capacity can be increased, and the radial load-bearing capacity can also be increased as a whole as the gear device 1A.

[0194] Furthermore, in this embodiment, the retaining structures for the plurality of pins 23 and the plurality of bearing pins 63 are different. The term "different retaining structures" as used in this disclosure refers to certain differences between the retaining structures used to retain the pins 23 and the retaining structures used to retain the bearing pins 63. As an example, as explained in the basic structure, the housings with different shapes (depths) for the gear side groove 222 serving as the retaining structure for the pins 23 and the bearing side groove 622 serving as the retaining structure for the bearing pins 63 are also included in the category of "different retaining structures." As another example, the housings with different materials or hardness, etc., in the retaining structures for the plurality of pins 23 and the plurality of bearing pins 63 are also included in the category of "different retaining structures."

[0195] In this embodiment, firstly, similar to the basic structure, the depth D1 of the gear side groove 222 (refer to...) Figure 4 The depth D2 of the bearing side groove 622 (refer to) Figure 14 The depths of the multiple gear side grooves 222 and the multiple bearing side grooves 622 are different (D1>D2). Specifically, the bearing side groove 622 has a diameter of the bearing pin 63 when viewed from one side in the direction of the rotation axis Ax1. The groove has an arc-shaped bottom surface with a diameter greater than the above. In other words, the bottom surface of the bearing side groove 622 has a larger radius of curvature than the bottom surface of the gear side groove 222. As an example, the bottom surface of the bearing side groove 622 has the same radius of curvature as the bearing pin 63. Moreover, the bearing side groove 622 is shallower than the gear side groove 222.

[0196] Furthermore, in this embodiment, the diameter of pin 23 Diameter of bearing pin 63 different However, compared to the multiple gear side grooves 222, the ratio of the depth of the multiple bearing side grooves 622 to the diameter of the retaining pin is set smaller. That is, the depth D2 of the bearing side groove 622 is smaller relative to the diameter of the bearing pin 63. ratio The depth D1 of the gear side groove 222 relative to the diameter of the pin 23 ratio Small. In this embodiment, as an example, the depth D2 of the bearing side groove 622 is relative to the diameter of the bearing pin 63. ratio Less than "1 / 4".

[0197] In summary, in this embodiment, the difference between the retaining structure of pin 23 (gear side groove 222) and the retaining structure of bearing pin 63 (bearing side groove 622) includes not only the difference in depth (D1 and D2) but also the difference in the radius of curvature of the bottom surface. Thus, even though the machining of the main body 11 for forming the gear side groove 222 and bearing side groove 622 becomes more complex when the shapes of the gear side groove 222 and bearing side groove 622 are different, it is still possible to reliably retain pins 23 and bearing pins 63 with different diameters respectively.

[0198] Furthermore, in this embodiment, since the outer diameters (diameters) of pins 23 and bearing pins 63 are different, the central axis Ax2, which serves as the center of rotation (self-rotation) of pin 23, and the central axis Ax3, which serves as the center of rotation (self-rotation) of bearing pin 63, are offset from each other. In other words, the plurality of bearing pins 63 and the plurality of pins 23 are not concentrically arranged. In this embodiment, as... Figure 13 As shown, the central axis Ax3 of bearing pin 63 is located inside the central axis Ax2 of pin 23 (on the side of the rotating axis Ax1).

[0199] Furthermore, in this embodiment, the diameter of the support body 8 (outer peripheral surface 81) is smaller than the diameter of the virtual circle (tip circle) at the front end of the internal tooth 21 of the internal gear 2. Therefore, the outer peripheral surface 81 of the support body 8 does not contact the plurality of pins 23, creating a gap between the outer peripheral surface 81 of the support body 8 and the plurality of pins 23.

[0200] As a variation of implementation method 1, such asFigure 15 As shown, each of the plurality of bearing pins 63 can be integrally formed with each of the plurality of pins 23. That is, in Figure 15 In this example, a pin is extended axially, with one part functioning as bearing pin 63 and the other part functioning as pin 23. Here, due to the diameter of bearing pin 63... Diameter of pin 23 Because they are different, the central axis Ax2, which serves as the center of rotation (self-rotation) of pin 23, is aligned with the central axis Ax2, which serves as the center of rotation (self-rotation) of bearing pin 63. This allows the integrated pin 23 and bearing pin 63 to rotate around the central axis Ax2. In this modified structure, pin 23 rotates together with bearing pin 63 and cannot rotate independently, but this reduces the number of components.

[0201] As another variation of embodiment 1, the second bearing member 7 can be omitted appropriately. That is, the gear device 1A only needs to have an internal gear 2, a planetary gear 3, multiple internal pins 4 and a first bearing member 6A, and the second bearing member 7 can be omitted.

[0202] As another variation of embodiment 1, the diameter of bearing pin 63 is... It can be compared to the diameter of pin 23. Small. Furthermore, the number of bearing pins 63 and 23 can be different.

[0203] Furthermore, as another variation of Embodiment 1, the diameter of the outer peripheral surface 81 of the support 8 can be the same as the diameter of the virtual circle (tip circle) passing through the front end of the internal tooth 21 in the internal gear 2. In this case, similar to the basic structure, the support 8 is positioned by contacting the outer peripheral surface 81 with the plurality of pins 23.

[0204] The structure of Embodiment 1 (including variations) can be appropriately combined with the structure (including variations) described in the basic structure.

[0205] (Implementation Method 2)

[0206] like Figure 16 and Figure 17 As shown, the structure of the first bearing member 6B in the internal meshing planetary gear device 1B of this embodiment (hereinafter also simply referred to as "gear device 1B") differs from that of the gear device 1A in Embodiment 1. Hereinafter, the same reference numerals will be used to refer to structures identical to those in Embodiment 1, and descriptions will be omitted as appropriate. Figure 16 This is a schematic cross-sectional view of gear assembly 1B. Figure 17 yes Figure 16 The sectional view along line B1-B1 and its enlarged partial view. However, in Figure 17In the middle, for components other than the eccentric shaft 54 ​​and the cage 64, although they are in cross-section, the cross-sectional lines are omitted.

[0207] In this embodiment, the first bearing member 6B is configured such that a plurality of bearing pins 63 are movable relative to the first outer ring 62 in the circumferential direction of the first outer ring 62. On the other hand, in the internal gear 2, similar to embodiment 1, the relative movement of the plurality of pins 23 relative to the gear body 22 in the circumferential direction of the gear body 22 is restricted. Therefore, the plurality of bearing pins 63 are movable relative to the plurality of pins 23 in the circumferential direction of the first outer ring 62. As a result, in the gear device 1B of this embodiment, the plurality of bearing pins 63 rotate relative to the plurality of pins 23 as the plurality of inner pins 4 rotate relative to the gear body 22.

[0208] Specifically, the first bearing component 6B has Industrial Utility The cage 64 (retainer) is shown. A plurality of bearing pins 63 are respectively arranged in a rotatable state between the inner circumferential surface 621 of the first outer ring 62 and the outer circumferential surface 611 of the first inner ring 61, and are held by the cage 64. The cage 64 holds the plurality of bearing pins 63 at equal intervals in the circumferential direction of the first outer ring 62. Furthermore, the cage 64 is not fixed relative to the inner circumferential surface 621 of the first outer ring 62 and the outer circumferential surface 611 of the first inner ring 61, and can rotate relative to the first inner ring 61 and the first outer ring 62 respectively about the rotation axis Ax1. Thus, with the rotation of the cage 64, the plurality of bearing pins 63 held by the cage 64 move along the circumferential direction of the first outer ring 62. In other words, the retaining structure for the plurality of bearing pins 63 includes the cage 64 disposed between the first outer ring 62 and the first inner ring 61. The cage 64 is, for example, made of metal.

[0209] In summary, in this embodiment, the retaining structure of pin 23 is a gear side groove 222, while the retaining structure of bearing pin 63 is a cage 64. The retaining structures of pin 23 and bearing pin 63 differ in their manner. In this case, it is sufficient to form only the gear side groove 222 as the retaining structure for the main body 11, thus simplifying the machining of the main body 11.

[0210] As a variation of embodiment 2, the diameter of bearing pin 63 is... It can be used with the diameter of pin 23 same The diameter of bearing pin 63 It can be compared to the diameter of pin 23. Small.

[0211] As another variation of embodiment 2, the cage 64 is not necessary, as long as the multiple inner pins 4 can rotate relative to the multiple bearing pins 63 relative to the multiple pins 23 along with the relative rotation of the multiple inner pins 4 relative to the gear body 22. Moreover, the material of the cage 64 is not limited to metal; for example, it can be a resin such as engineering plastic.

[0212] The structure of Embodiment 2 (including variations) can be appropriately combined with the basic structure or the structure described in Embodiment 1 (including variations).

[0213] (Summarize)

[0214] As described above, the first-type internal meshing planetary gear assembly (1, 1A, 1B) includes an internal gear (2), a planetary gear (3), multiple inner pins (4), and a first bearing member (6, 6A, 6B). The internal gear (2) has an annular gear body (22) and multiple pins (23) that are held in a rotatable state on the inner circumferential surface (221) of the gear body (22) and form internal teeth (21). The planetary gear (3) has external teeth (31) that partially mesh with the internal teeth (21). The multiple inner pins (4) revolve within the multiple inner pin holes (32) formed in the planetary gear (3) and rotate relative to the gear body (22). The first bearing member (6, 6A, 6B) rotatably supports the multiple inner pins (4) on the gear body (22). The first bearing component (6, 6A, 6B) has a first inner ring (61) and a first outer ring (62), and a plurality of bearing pins (63). The plurality of bearing pins (63) are held between the first inner ring (61) and the first outer ring (62) in a rotatable state. The plurality of pins (23) and the plurality of bearing pins (63) have different diameters and different holding structures.

[0215] According to this configuration, the first bearing component (6, 6A, 6B) is a needle roller bearing with bearing pins (63) as "rolling elements (rollers)," which can withstand relatively large radial loads. Moreover, since the diameters of the multiple pins (23) and the multiple bearing pins (63) are different, and their retaining structures are also different, the diameters of the bearing pins (63) and the retaining structures are designed to easily withstand various envisioned loads. Therefore, it has the advantage of easily achieving structural simplification.

[0216] In the second form of the internal meshing planetary gear assembly (1, 1A, 1B), based on the first form, the retaining structure for the multiple pins (23) includes multiple gear side grooves (222) formed on the inner circumferential surface (221) of the gear body (22). The retaining structure for the multiple bearing pins (63) includes multiple bearing side grooves (622) formed on the inner circumferential surface (621) of the first outer ring (62). The depths of the multiple gear side grooves (222) and the multiple bearing side grooves (622) are different.

[0217] According to this configuration, different retention structures for multiple pins (23) and multiple bearing pins (63) can be achieved by varying the depths of the gear side groove (222) and the bearing side groove (622).

[0218] The third form of the internal meshing planetary gear device (1, 1A, 1B) is based on the first form, with multiple inner pins (4) rotating relative to the gear body (22) and multiple bearing pins (63) rotating relative to multiple pins (23).

[0219] According to this configuration, since the positions of the multiple bearing pins (63) change relative to the multiple pins (23), it is difficult for the load to be concentrated on a portion of the bearing pins (63).

[0220] In the fourth form of the internal meshing planetary gear assembly (1, 1A, 1B), based on the third form, the retaining structure of the plurality of bearing pins (63) includes a cage (64) disposed between the first outer ring (62) and the first inner ring (61).

[0221] According to this configuration, the spacing of multiple bearing pins (63) can be maintained by using a retainer (64).

[0222] In the fifth form of the internal meshing planetary gear device (1, 1A, 1B), based on any one of the first to fourth forms, each of the plurality of bearing pins (63) is concentrically arranged with each of the plurality of pins (23).

[0223] Based on this configuration, it is easy to synchronize the rotation of the bearing pin (63) with the rotation of the pin (23).

[0224] In the sixth form of the internal meshing planetary gear device (1, 1A, 1B), based on any one of the first to fifth forms, each of the multiple bearing pins (63) is integrated with each of the multiple pins (23).

[0225] Based on this form, it is easy to keep the number of parts to a minimum.

[0226] The seventh form of the internal meshing planetary gear assembly (1, 1A, 1B) is based on any one of the first to sixth forms and also includes a second bearing member (7). Together with the first bearing member (6, 6A, 6B), the second bearing member (7) rotatably supports multiple inner pins (4) on the gear body (22) at two locations in the direction of the rotation axis (Ax1).

[0227] According to this configuration, it is easier to withstand loads such as bending force (bending moment load) on the rotating shaft (Ax1) compared to a single support where multiple inner pins (4) are supported on the gear body (22) at one location in the direction of the rotating shaft (Ax1).

[0228] In the eighth form of the internal meshing planetary gear device (1, 1A, 1B), based on the seventh form, when viewed from one side in the direction of the rotation axis (Ax1), multiple inner pins (4) are located inside the second bearing member (7).

[0229] Based on this form, the limited space inside the multiple inner pins (4) can be set into a relatively simple structure.

[0230] In the ninth form of the internal meshing planetary gear device (1, 1A, 1B), based on the seventh or eighth form, the first bearing member (6, 6A, 6B) pin and the second bearing member (7) are located on the same side in the direction of the rotation axis (Ax1) relative to the multiple pins (23).

[0231] Based on this configuration, multiple inner pins (4) can be effectively supported at two points, and miniaturization in the direction of the rotation axis (Ax1) can be easily achieved.

[0232] In the tenth embodiment of the internal meshing planetary gear assembly (1, 1A, 1B), based on any one of the first to ninth embodiments, the retaining structure for the plurality of pins (23) includes a plurality of gear side grooves (222) formed on the inner circumferential surface (221) of the gear body (22). The retaining structure for the plurality of bearing pins (63) includes a plurality of bearing side grooves (622) formed on the inner circumferential surface (621) of the first outer ring (62). Compared to the plurality of gear side grooves (222), the depth of the plurality of bearing side grooves (622) is smaller in ratio to the diameter of the retaining pin.

[0233] Based on this configuration, it is easy to reduce the frictional resistance between the inner surface of the bearing side groove (622) and the bearing pin (63).

[0234] In the eleventh form of the internal meshing planetary gear device (1, 1A, 1B), based on any one of the first to tenth forms, it is configured such that when the multiple inner pins (4) rotate relative to the gear body (22), the rotational force of the gear body (22) is taken out as the output.

[0235] According to this configuration, the gear body (22) or a component integrated with the gear body (22) can be used as a rotating component.

[0236] The twelfth type of wheel assembly (W1) includes: an internal meshing planetary gear assembly (1, 1A, 1B) of any of the first to eleventh types; and a wheel body (102) that rolls on the travel surface by rotational output when multiple inner pins (4) rotate relative to the gear body (22).

[0237] Based on this form, it has the advantage of easily simplifying the structure.

[0238] The vehicle in the thirteenth form (V1) includes the wheel assembly (W1) of the twelfth form and the body (100) that holds the wheel assembly (W1).

[0239] Based on this form, it has the advantage of easily simplifying the structure.

[0240] Regarding the structures of the second to eleventh forms, these are not essential for the internal meshing planetary gear devices (1, 1A, 1B) and can be omitted appropriately.

[0241] Explanation of reference numerals in the attached figures

[0242] 1. 1A, 1B Internal meshing planetary gear assembly

[0243] 2 Internal gears

[0244] 3 planetary gears

[0245] 4. Domestic sales

[0246] 6, 6A, 6B First Bearing Components

[0247] 7 Second bearing component

[0248] 21 internal teeth

[0249] 22 Gear Body

[0250] 23 sales

[0251] 31 external teeth

[0252] 32-hole inner pin

[0253] 61 First Inner Circle

[0254] 62 First Outer Ring

[0255] 63 bearing pin

[0256] 64 cages

[0257] 71 Second Inner Circle

[0258] 72 Second Outer Ring

[0259] 100 body

[0260] 102 wheel body

[0261] 221 (inner circumferential surface of the gear body)

[0262] 222 Gear Side Groove

[0263] 621 (the inner circumferential surface of the first outer ring)

[0264] 622 bearing side groove

[0265] Ax1 Rotational Axis

[0266] V1 vehicles

[0267] W1 wheel assembly

[0268] ​

[0269] According to embodiments of this disclosure, a simplified internal meshing planetary gear assembly, wheel assembly, and vehicle with an easily achievable structure can be provided.

Claims

1. An internal gear planetary gear arrangement, wherein, Comprising: an internally toothed gear having a ring-shaped gear body and a plurality of pins held in a self-rotatable state to an inner circumferential surface of the gear body and constituting internal teeth; a planetary gear having external teeth that partially mesh with the internal teeth; a plurality of internal pins that, in a state of being respectively inserted into a plurality of internal pin holes formed in the planetary gear, revolve in the internal pin holes and relatively rotate with respect to the gear body; and a first bearing member that rotatably supports the plurality of internal pins to the gear body, the first bearing member has: a first inner ring and a first outer ring; and a plurality of bearing pins held in a self-rotatable state between the first inner ring and the first outer ring, for the plurality of pins and the plurality of bearing pins, respective diameters are different and holding structures are different.

2. The internally toothed planetary gear device according to claim 1, wherein the holding structure of the plurality of pins includes a plurality of gear-side grooves formed in the inner circumferential surface of the gear body, the holding structure of the plurality of bearing pins includes a plurality of bearing-side grooves formed in the inner circumferential surface of the first outer ring, for the plurality of gear-side grooves and the plurality of bearing-side grooves, respective depths are different.

3. The internally toothed planetary gear device according to claim 1, wherein the plurality of bearing pins relatively rotate with respect to the plurality of pins in conjunction with relative rotation of the plurality of internal pins with respect to the gear body.

4. The internally toothed planetary gear device according to claim 3, wherein the holding structure of the plurality of bearing pins includes a retainer arranged between the first outer ring and the first inner ring.

5. The internally toothed planetary gear device according to any one of claims 1 to 4, wherein each of the plurality of bearing pins is arranged concentrically with each of the plurality of pins.

6. The internally toothed planetary gear device according to any one of claims 1 to 5, wherein each of the plurality of bearing pins is integral with each of the plurality of pins.

7. The internally toothed planetary gear device according to any one of claims 1 to 6, wherein the internally toothed planetary gear device further includes a second bearing member that, together with the first bearing member, rotatably supports the plurality of internal pins to the gear body at two positions in a rotational axis direction.

8. The internally toothed planetary gear device according to claim 7, wherein the plurality of internal pins are located inside the second bearing member when viewed from one side in the rotational axis direction.

9. The internally toothed planetary gear device according to claim 7 or 8, wherein the first bearing member and the second bearing member are located on the same side in the rotational axis direction with respect to the plurality of pins.

10. The internally toothed planetary gear device according to any one of claims 1 to 9, wherein the holding structure of the plurality of pins includes a plurality of gear-side grooves formed in the inner circumferential surface of the gear body, the holding structure of the plurality of bearing pins includes a plurality of bearing-side grooves formed in the inner circumferential surface of the first outer ring, the plurality of bearing-side grooves have a smaller ratio of depth to diameter of the held pins than the plurality of gear-side grooves. ​ 11. The internal gear wheel device according to any one of claims 1 to 10, wherein is configured to take out the rotational force of the gear body as an output when the plurality of internal pins are relatively rotated with respect to the gear body.

12. A wheel arrangement, wherein, comprises: the internal gear wheel device according to any one of claims 1 to 11; and a wheel body that rolls on a traveling surface by the rotational output when the plurality of internal pins are relatively rotated with respect to the gear body.

13. A vehicle, wherein, comprises: the wheel device according to claim 12; and a vehicle body that holds the wheel device.

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