Eccentric oscillating gear device

Abstract

Provided is an eccentric oscillation type gear device that can reduce the number of components. An eccentric oscillation type gear device according to one embodiment is an eccentric oscillation type gear device that includes an oscillation gear (84), a crankshaft (11) having an eccentric body (12, 13) that causes the oscillation gear to oscillate, an eccentric bearing (34, 35) disposed between the oscillation gear and the eccentric body, and a flange member (86) disposed in opposition to the crankshaft in the axial direction. The crankshaft has a hollow portion (112), the flange member has a shaft member (38) inserted into the hollow portion, an inner bearing (30) is disposed between an inner periphery (114) of the crankshaft and an outer periphery (383) of the shaft member, the gear device further has a restriction member (41) that is integrated with the crankshaft and restricts movement of the eccentric bearing in the axial direction, and the restriction member has a link portion (44) that links a power transmission member (82) that transmits power to the crankshaft.

Description

[0001] This application claims priority based on Japanese Patent Application No. 2021-116493, filed on July 14, 2021. The entire contents of that Japanese application are incorporated herein by reference. Technical Field

[0002] This invention relates to an eccentric oscillating gear device. Background Technology

[0003] Patent Document 1 describes a gear device that reduces the rotation transmitted to a crankshaft before outputting it. This gear device includes a crankshaft that causes a oscillating gear to oscillate and rotate, and a flange member having a shaft member inserted into a hollow portion of the crankshaft. An inner bearing is disposed between the inner circumference of the crankshaft and the outer circumference of the shaft member, and an eccentric bearing is disposed between an eccentric body disposed on the crankshaft and the oscillating gear.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2017-141915

[0005] In the gear device described in Patent Document 1, multiple positioning components such as spacers or retaining rings are used to limit the axial position of components such as flange members, inner bearings, and eccentric bearings within a specified range, resulting in a large number of components. A large number of components increases the cost of processing or assembling them, thus putting the device at a cost disadvantage. Summary of the Invention

[0006] The present invention was made in view of this situation, and its object is to provide an eccentric oscillating gear device that can reduce the number of components.

[0007] To address the aforementioned issues, a gear device according to one embodiment of the present invention includes a oscillating gear, a crankshaft having an eccentric body that causes the oscillating gear to oscillate and rotate, an eccentric bearing disposed between the oscillating gear and the eccentric body, and a flange member disposed axially opposite to the crankshaft, wherein the crankshaft has a hollow portion. The flange member has a shaft member inserted into the hollow portion. An inner bearing is disposed between the inner circumference of the crankshaft and the outer circumference of the shaft member. The gear device further includes a limiting member integral with the crankshaft and restricting axial movement of the eccentric bearing. The limiting member has a connecting portion for connecting a power transmission member that transmits power to the crankshaft.

[0008] Another embodiment of the present invention is also a gear device. This device includes a oscillating gear, a crankshaft having an eccentric body that causes the oscillating gear to oscillate and rotate, an eccentric bearing disposed between the oscillating gear and the eccentric body, and a flange member disposed axially opposite to the crankshaft, wherein the crankshaft has a hollow portion. The flange member has a shaft member inserted into the hollow portion. An inner bearing is disposed between the inner circumference of the crankshaft and the outer circumference of the shaft member. The gear device also has a limiting member integrated with the crankshaft that restricts axial movement of the eccentric bearing. The limiting member further restricts axial movement of the inner bearing.

[0009] Furthermore, any combination of the above-mentioned constituent elements, or the substitution of the constituent elements of the present invention with each other in methods, systems, etc., is also effective as an embodiment of the present invention.

[0010] According to the present invention, an eccentric oscillating gear device capable of reducing the number of components is provided. Attached Figure Description

[0011] Figure 1 This is a side sectional view of the eccentric oscillating gear device according to the first embodiment.

[0012] Figure 2 This is a side sectional view of the eccentric oscillating gear device of the second embodiment.

[0013] Figure 3 This is a side sectional view of the eccentric oscillating gear device of the third embodiment.

[0014] In the diagram: 100-Gear assembly, 11-Crankshaft, 12, 13-Eccentric body, 14, 15-External gear, 16-Internal gear, 18-Gear frame, 30-Inner bearing, 34, 35-Eccentric bearing, 38-Shaft component, 41-Input side limiting component, 42-Input opposite side limiting component, 44-Connecting part, 46-Inner limiting component, 82-Power transmission component, 84-Oscillating gear, 86-Flange component, 112-Hollow part, 114-Inner circumference, 116-Outer circumference protrusion, 118-Threaded hole, 383-Outer circumference. Detailed Implementation

[0015] Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. In the embodiments and variations, identical or equivalent constituent elements and components are labeled with the same symbols, and repeated descriptions are omitted where appropriate. Furthermore, in the accompanying drawings, the dimensions of components are appropriately enlarged or reduced for ease of understanding. Also, in the accompanying drawings, parts of components that are not essential to the description of the embodiments are omitted.

[0016] Furthermore, for constituent elements that share commonalities, they are distinguished by being marked with numbers such as "1st", "2nd", etc., at the beginning of their names, and these numbers are omitted when referring to them collectively. The terms including numbers such as "1st", "2nd", etc., are used to describe various constituent elements; however, these terms are only used to distinguish one constituent element from others, and are not used to limit the constituent elements.

[0017] [First Implementation]

[0018] The following is for reference. Figure 1 The structure of the eccentric oscillating gear device 100 (hereinafter simply referred to as "gear device 100") according to the first embodiment of the present invention will be described. Figure 1 This is a schematic side sectional view of the gear assembly 100. The gear assembly 100 includes: a crankshaft 11; eccentric bodies 12 and 13; external gears 14 and 15; internal gear 16; eccentric bearings 34 and 35; a wheel carrier 18; limiting members 41 and 42; a power transmission member 82; a connecting part 44; an inner limiting member 46; housings 21, 22, and 23; a cover 20; and a main bearing 24.

[0019] Hereinafter, the direction along the central axis La of the internal gear 16 will be referred to as the "axial direction," and the circumferential direction and radial direction of the circle centered on the central axis La will be referred to as the "circumferential direction" and "radial direction," respectively. Furthermore, for ease of explanation, the side along the axial direction (right side in the figure) will be referred to as the input side, and the other side along the axial direction (left side in the figure) will be referred to as the opposite input side. This directional marking does not restrict the operating posture of the gear device 100; the gear device 100 can be used in any posture.

[0020] One of the external gears 14 and 15 and the internal gear 16 functions as an oscillating gear 84, while the other functions as a non-oscillating gear 85. In this example, the external gears 14 and 15 function as oscillating gears 84, and the internal gear 16 functions as a non-oscillating gear 85.

[0021] The gear assembly 100 is a central crank-type planetary gear assembly with the central axis La of the crankshaft 11 and the internal gear 16 coaxially arranged. In the gear assembly 100, if the eccentric bodies 12 and 13 rotate eccentrically as part of the crankshaft 11, this eccentric rotation causes the external gears 14 and 15 to oscillate via the eccentric bearings 34 and 35. In the gear assembly 100, the relative rotation between the external gears 14 and 15 and the internal gear 16 obtained by the oscillation of the external gears 14 and 15 is output from the gear carrier 18 via the inner pin 19.

[0022] The housings 21, 22, and 23 function as housings for components of the gear assembly 100, such as the external gears 14 and 15. In this embodiment, the housings 21, 22, and 23 are constructed by combining multiple housing components. In this example, the housings 21, 22, and 23 are composed of a first housing component 21, a second housing component 22 disposed on the input side of the first housing component 21, and a third housing component 23 disposed on the input side of the second housing component 22. In this example, the first housing component 21, the second housing component 22, and the third housing component 23 are connected together by bolts B4.

[0023] The crankshaft 11 has a hollow portion 112, and the wheel carrier 18 has a shaft member 38 inserted into the hollow portion 112. An inner bearing 30 is disposed between the inner periphery 114 of the crankshaft 11 and the outer periphery 383 of the shaft member 38. The gear assembly 100 has limiting members 41 and 42 integrated with the crankshaft 11 and limiting the axial movement of the eccentric bearings 34 and 35. The limiting members 41 and 42 have a connecting portion 44 for connecting to a power transmission member 82 that transmits power to the crankshaft 11. The limiting members 41 and 42 include an input-side limiting member 41 disposed on the input side of the eccentric bearings 34 and 35 and an input-opposite-side limiting member 42 disposed on the opposite input side of the eccentric bearings 34 and 35.

[0024] The crankshaft 11 is an annular component having a hollow portion 112 formed in the shaft body 111, and is coaxially arranged with the central axis La. The crankshaft 11 is rotatable by rotational power transmitted from the motor 96. In this embodiment, two eccentric bodies 12 and 13, offset from each other by 180°, are provided on the outer periphery of the shaft body 111 of the crankshaft 11. The eccentric bodies 12 and 13 cause the external gears 14 and 15 to oscillate. The first eccentric body 12 of the two eccentric bodies 12 and 13 is arranged on the input side of the second eccentric body 13.

[0025] The crankshaft 11 has a flange-shaped peripheral protrusion 116 protruding radially from its outer peripheral surface. The crankshaft 11 has a plurality of (e.g., three) threaded holes 118 disposed on the input-side end face. The plurality of threaded holes 118 are arranged at positions offset from the central axis La and spaced at predetermined intervals circumferentially. The crankshaft 11 also has a plurality of (e.g., three) threaded holes 119 disposed on the opposite input-side end face. The plurality of threaded holes 119 are arranged at positions offset from the center and spaced at predetermined intervals circumferentially.

[0026] The axes of eccentric bodies 12 and 13 are eccentric relative to the central axis La of the internal gear 16. Eccentric bodies 12 and 13 rotate around the central axis La, and are oscillated by external gears 14 and 15. External gears 14 and 15 are respectively provided corresponding to each eccentric body 12 and 13, and are rotatably supported on the corresponding eccentric bodies 12 and 13 via eccentric bearings 34 and 35. The first eccentric bearing 34 of the eccentric bearings 34 and 35 is located on the input side of the second eccentric bearing 35.

[0027] exist Figure 1 In this example, the power transmission component 82 is the input gear 28. The input gear 28 meshes with a pinion 98 connected to the motor shaft of the motor 96. If the motor 96 drives the pinion 98 to rotate, the rotation after being shifted by the pinion 98 and the input gear 28 is input to the crankshaft 11. The input gear 28 functions as a power transmission component that transmits power to the crankshaft 11.

[0028] External gears 14 and 15 have central holes 142 and 152 passing through their centers, and multiple (e.g., six) inner pin holes 144 and 154 passing through their centers at positions offset from their central axes La. Inner pins 19 are inserted into the inner pin holes 144 and 154. The teeth formed on the outer circumference of the external gears 14 and 15 rotate while meshing with the teeth of the internal gear 16, thereby causing the external gears 14 and 15 to oscillate. The first external gear 14 is positioned on the input side of the second external gear 15. A spacer 17 is disposed between the first external gear 14 and the second external gear 15.

[0029] The cover 20 is a thin plate-like component disposed on the input side of the first external gear 14, and it restricts the first external gear 14 from moving axially toward the input side. The cover 20 is fixed to the input side of the first housing component 21 by bolts B1. The second external gear 15 is disposed on the input side of the wheel carrier 18, and the wheel carrier 18 restricts the second external gear 15 from moving axially toward the opposite side of the input.

[0030] The inner pin 19 extends axially from the input side of the wheel carrier 18 through the inner pin holes 144 and 154. The input side end of the inner pin 19 extends to the vicinity of the cover 20.

[0031] The internal gear 16 is integrated with the housings 21, 22, and 23. In this example, the internal gear 16 is formed by the first housing component 21.

[0032] In this embodiment, the wheel carrier 18 is positioned on the opposite side of the input of the second external gear 15. The wheel carrier 18 rotates synchronously with the rotational components of the external gears 14 and 15, and outputs its rotational components to the driven device (not shown). Alternatively, the internal gear 16 can be rotated instead of the wheel carrier 18, and its rotational components can be output to the driven device via the housings 21, 22, and 23.

[0033] As described above, the wheel carrier 18 functions as a flange axially opposed to the crankshaft 11. The wheel carrier 18 has a circular wheel carrier body 182, a plurality of inner pins 19 protruding from the wheel carrier body 182 toward the input side, and a circumferential protrusion 184 protruding from the wheel carrier body 182 toward the input side. The wheel carrier body 182 and the circumferential protrusion 184 have a through hole (i.e., a wheel carrier hole 186) coaxially arranged with the central axis La.

[0034] The shaft component 38 includes: a cylindrical shaft body 382 with an outer periphery 383; and an extension protrusion 384 extending axially from the input side of the shaft body 382. The extension protrusion 384 is formed such that its diameter is smaller than the diameter of the shaft body 382, ​​and has a circumferential groove G1 for the washer W1 to fit into. In this example, the shaft component 38 is constructed from a different component from the wheel carrier 18, and is integrally formed with the wheel carrier 18, for example, by pressing it into the wheel carrier hole 186. Alternatively, the shaft component 38 and the wheel carrier 18 may also be formed as a single component.

[0035] Multiple inner pins 19 are cylindrical portions disposed at predetermined intervals along the circumference, offset from the central axis La. The inner pins 19 are inserted into the inner pin holes 144 and 154 of the external gears 14 and 15.

[0036] The main bearing 24 supports the wheel carrier 18 so that it can rotate freely relative to the housings 21, 22, and 23. In this example, the main bearing 24 is positioned on the opposite side of the input of the external gears 14 and 15 and between the outer periphery of the wheel carrier 18 and the second housing component 22 and the third housing component 23. The structure of the main bearing 24 is not limited, but in this example, the main bearing 24 is a crossed roller bearing.

[0037] The input-side limiting member 41 is a hollow annular member having a hollow portion 411 coaxially arranged with the central axis La. The input-side limiting member 41 has a hollow, disc-shaped portion 416 and a circumferentially shaped protrusion 418 protruding axially from the inner circumferential side of the disc portion 416 toward the input side. The disc portion 416 is axially opposed to the input side of the crankshaft 11. The circumferentially shaped protrusion 418 is circumferentially shaped and fits into the inner circumference 114 of the crankshaft 11. The circumferentially shaped protrusion 418 is opposed to the input-side side of the inner bearing 30. According to this structure, the input-side limiting member 41 also restricts the inner bearing 30 from moving axially toward the input side.

[0038] The input-side limiting member 41 has a connecting portion 44 for connecting to the power transmission member 82 (i.e., the input gear 28) that transmits power to the crankshaft 11. In this embodiment, the connecting portion 44 is a threaded hole 412 for fixing the input gear 28 by bolts. In this example, a plurality of (e.g., three) threaded holes 412 are formed on the disc portion 416 of the input-side limiting member 41. The plurality of threaded holes 412 are arranged at positions offset from the central axis La and at predetermined intervals in the circumferential direction. In this example, the threaded holes 412 penetrate the input-side limiting member 41 axially.

[0039] The input gear 28 has a through hole 282 located at a position corresponding to the threaded hole 412. The input gear 28 is connected to the input side limiting member 41 by screwing a bolt B5 inserted from the input side into the through hole 282 into the threaded hole 412.

[0040] A plurality of (e.g., three) through holes 414 are provided through the disc portion 416 of the input-side limiting member 41. These through holes 414 are arranged at positions offset from the central axis La of the disc portion 416 and are spaced apart circumferentially. The through holes 414 are formed at positions corresponding to the threaded holes 118 of the crankshaft 11. By screwing a bolt B2 inserted from the input side into the through hole 414 into the threaded hole 118, the input-side limiting member 41 is connected to the crankshaft 11 and integrated with the crankshaft 11.

[0041] The input-opposite-side limiting member 42 is a hollow annular member coaxially arranged with the central axis La. The input-opposite-side limiting member 42 has a hollow disk-shaped portion 422 and a hollow circumferential protrusion 424 protruding axially from the inner circumference of the disk portion 422 toward the input side. The disk portion 422 is axially opposed to the input-opposite side of the crankshaft 11. The circumferential protrusion 424 fits into the inner circumference 114 of the crankshaft 11.

[0042] A plurality of (e.g., three) through holes 426 are provided through the disc portion 422 of the input-opposite-side limiting member 42. These through holes 426 are arranged at positions offset from the central axis La of the disc portion 422 and are spaced apart circumferentially. The through holes 426 are formed at positions corresponding to the threaded holes 119 of the crankshaft 11. By screwing a bolt B3 inserted from the input-opposite-side into the through holes 426 and into the threaded holes 119, the input-opposite-side limiting member 42 is connected to the crankshaft 11 and integrated with the crankshaft 11.

[0043] Eccentric bearings 34 and 35 have a plurality of rolling elements 342 and 352 arranged circumferentially at predetermined intervals on the outer periphery of eccentric bodies 12 and 13 of crankshaft 11. Eccentric bearings 34 and 35 may or may not have cages. Eccentric bearings 34 and 35 may have inner and / or outer rings, but in this example, they do not have dedicated inner and outer rings. The outer periphery of eccentric bodies 12 and 13 functions as the inner ring side rolling surface, and the inner periphery of external gears 14 and 15 functions as the outer ring side rolling surface. Rolling elements 342 are axially held by an input-side limiting member 41 and an outer peripheral protrusion 116. The input-side limiting member 41 restricts the axial movement of rolling elements 342 toward the input side, and the outer peripheral protrusion 116 restricts the axial movement of rolling elements 342 toward the opposite input side. Rolling elements 352 are axially held by an input-opposite-side limiting member 42 and an outer peripheral protrusion 116. The input-opposite-side limiting member 42 restricts the rolling element 352 from moving axially toward the input-opposite side, and the outer peripheral protrusion 116 restricts the rolling element 352 from moving axially toward the input side.

[0044] As described above, the inner bearing 30 is disposed between the inner periphery 114 of the crankshaft 11 and the outer periphery 383 of the shaft member 38. The inner bearing 30 has a plurality of rolling elements 302 disposed circumferentially at predetermined intervals on the outer periphery of the shaft member 38. The rolling elements 302 are cylindrical rollers. The rolling elements 302 are axially held by the circumferential protrusion 418 of the input-side limiting member 41 and the circumferential protrusion 424 of the input-opposite-side limiting member 42. The circumferential protrusion 418 restricts the rolling elements 302 from moving axially toward the input side, and the circumferential protrusion 424 restricts the rolling elements 302 from moving axially toward the input-opposite side.

[0045] Multiple (e.g., two) inner bearings 30 may be provided axially, but in this example, a single bearing is used. The inner bearing 30 may have an inner ring and / or an outer ring, but in this example, there are no dedicated inner and outer rings. The outer periphery 383 of the shaft component 38 functions as the inner ring-side rolling surface, and the inner periphery 114 of the crankshaft 11 functions as the outer ring-side rolling surface. The inner bearing 30 may or may not have a cage.

[0046] The inner limiting member 46 is a hollow annular member coaxially arranged with the central axis La. The inner limiting member 46 is fixed to the shaft member 38 by a washer W1. In this example, the inner limiting member 46 fits into the outer periphery of the extended protrusion 384 of the shaft member 38. The washer W1, which fits into the circumferential groove G1 of the shaft member 38 on the input side of the inner limiting member 46, restricts the axial movement of the inner limiting member 46 toward the input side. The inner limiting member 46 is housed in the hollow portion 411 of the input side limiting member 41, and is axially opposed to the inner bearing 30 within the hollow portion 411. According to this structure, the axial movement of the inner bearing 30 toward the input side is restricted.

[0047] Next, the operation of the eccentric oscillating gear device 100 with the above-described structure will be explained. When rotational power is transmitted from the motor 96 to the crankshaft 11, the crankshaft 11 rotates around the rotation centerline La, and the eccentric bodies 12 and 13 cause the external gears 14 and 15 to oscillate. As the external gears 14 and 15 oscillate, the meshing positions of the external gears 14 and 15 with the internal gear 16 are sequentially offset circumferentially. As a result, for each revolution of the crankshaft 11, the external gears 14 and 15 rotate together with the gear carrier 18 by an amount equivalent to the difference in the number of teeth between the external gears 14 and 15 and the internal gear 16 (for example, 1). The rotation of the crankshaft 11 is reduced in speed by a reduction ratio corresponding to the difference in the number of teeth between the external gears 14 and 15 and the internal gear 16, and then output to the driven device via the gear carrier 18.

[0048] Next, the features of the eccentric oscillating gear device 100 with the above-described structure will be described. The gear device 100 is an eccentric oscillating gear device having an external gear 14 (oscillating gear 84), a crankshaft 11 having eccentric bodies 12 and 13 that cause the external gear 14 to oscillate and rotate, eccentric bearings 34 and 35 disposed between the external gear 14 and the eccentric bodies 12 and 13, and a wheel frame 18 (flange member 86) disposed axially opposite to the crankshaft 11. The crankshaft 11 has a hollow portion 112, and the wheel carrier 18 has a shaft component 38 inserted into the hollow portion 112. An inner bearing 30 is disposed between the inner periphery 114 of the crankshaft 11 and the outer periphery 383 of the shaft component 38. The gear assembly 100 also has limiting members 41 and 42 integrated with the crankshaft 11 and limiting the axial movement of the eccentric bearings 34 and 35. The limiting members 41 and 42 have a connecting portion 44 for connecting the input gear 28 (power transmission component 82) that transmits power to the crankshaft 11.

[0049] According to this structure, an inner bearing 30 is arranged between the inner periphery 114 of the crankshaft 11 and the outer periphery 383 of the shaft component 38. The limiting members 41 and 42 that restrict the movement of the inner bearing 30 also restrict the movement of the eccentric bearings 34 and 35, thereby making the gear assembly 100 more compact in the axial direction. Because of the shared components, the number of components can be reduced, which is advantageous in terms of cost.

[0050] Hereinafter, the second and third embodiments of the present invention will be described. In the drawings and descriptions of the second and third embodiments, the same or equivalent components and parts as those in the first embodiment are marked with the same symbols. Descriptions that are repeated in the first embodiment are omitted as appropriate, and the focus is on describing structures that are different from those in the first embodiment. Therefore, the descriptions of the first embodiment can be applied to the components and parts in the second and third embodiments that are the same or equivalent to those in the first embodiment.

[0051] [Second Implementation]

[0052] refer to Figure 2 The structure of the eccentric oscillating gear device 100 according to the second embodiment of the present invention will be described. Figure 2 This is a schematic side sectional view of the gear device 100 according to this embodiment. Figure 2 For ease of understanding, the gear assembly 100 is shown with the motor 96 disconnected.

[0053] The difference between this embodiment and the first embodiment is that the power transmission component 82 is a motor shaft 97 and the connecting portion 44 is a spline 419, while the other structures are the same as in the first embodiment. Therefore, the spline 419 will be mainly described. The spline 419 (internal teeth) is formed on the inner circumference of the hollow portion 411 of the input-side limiting component 41, and it is connected to the spline 93 (external teeth) formed on the motor shaft 97. By inserting the motor shaft 97 into the hollow portion 411, the spline 93 and the spline 419 mesh, and the input-side limiting component 41 is connected to the motor shaft 97.

[0054] The gear device 100 of this embodiment operates in the same manner as in the first embodiment and performs the same function and effect as in the first embodiment.

[0055] [Third Implementation]

[0056] refer to Figure 3 The structure of the eccentric oscillating gear device 100 according to the third embodiment of the present invention will be described. Figure 3 This is a schematic side sectional view of the gear device 100 according to this embodiment. The motor 96 and power transmission component 82 are omitted in this figure. This embodiment differs from the first embodiment in that the input-side protrusion 113 is provided on the crankshaft 11, the structure of the input-side limiting component 41 is different, the inner bearing 30 has an inner ring 304, and a spacer component 48 is provided; other structures are the same as in the first embodiment. Therefore, the input-side protrusion 113, the input-side limiting component 41, and the spacer component 48 will be mainly described. The inner ring 304 is an annular component surrounding the outer periphery 383 of the shaft component 38, and an inner ring-side rolling surface for the rolling element 302 to roll is provided on its outer periphery.

[0057] The input-side protrusion 113 is a hollow annular portion protruding from the shaft body 111 of the crankshaft 11 toward the input side, and it is formed as a single component with the shaft body 111. The diameter of the input-side protrusion 113 is smaller than the diameter of the shaft body 111, and it has a circumferential groove G2 for the retaining ring W2 to fit into. In this embodiment, the connecting portion 44 is a plurality of (e.g., three) threaded holes 117 formed in the input-side protrusion 113. The plurality of threaded holes 117 are provided through the input-side protrusion 113 at positions offset from the central axis La and arranged circumferentially at predetermined intervals.

[0058] The input-side limiting member in the first embodiment also restricts the axial movement of the inner bearing 30, but the input-side limiting member 41 in this embodiment does not restrict the movement of the inner bearing 30. In this example, the input-side limiting member 41 is axially opposed to the input side of the first eccentric bearing 34, thereby restricting the first eccentric bearing 34 from moving axially toward the input side. Figure 3 The input-side limiting member 41 is a hollow annular component coaxially arranged with the central axis La, and it fits into the outer periphery of the input-side protrusion 113. The input-side limiting member 41 is fixed to the input-side protrusion 113 by a retaining ring W2 embedded in the circumferential groove G2 provided on the outer periphery of the input-side protrusion 113.

[0059] In this embodiment, the spacer 48 is a hollow annular component coaxially arranged with the central axis La, and it fits into the outer periphery of the circumferential protrusion 184 of the wheel carrier 18. The spacer 48 is axially held by the wheel carrier 18, the crankshaft 11, and the inner bearing 30. In particular, the spacer 48 is disposed between the wheel carrier body 182 and the shaft body 111, and is configured to slide relative to the wheel carrier 18 and the crankshaft 11. According to this structure, the wheel carrier 18 functions as a limiting component that restricts the axial movement of the rolling elements 302 of the inner bearing 30, the crankshaft 11, and the rolling elements 352 of the second eccentric bearing 35 towards the opposite side of the input via the spacer 48.

[0060] In this embodiment, the inner limiting member 46 is fitted around the outer periphery of the shaft body 382 of the shaft member 38 and abuts against the input side portion of the input side protrusion 113. According to this structure, the inner limiting member 46 restricts the crankshaft 11 from moving axially toward the input side.

[0061] The gear device 100 of this embodiment operates in the same manner as in the first embodiment and performs the same function and effect as in the first embodiment.

[0062] The embodiments of the present invention have been described in detail above. These embodiments are merely specific examples for implementing the present invention. The descriptions of these embodiments are not intended to limit the technical scope of the present invention; various design changes, such as alterations, additions, and deletions of constituent elements, are possible without departing from the inventive concept specified in the technical solution. In the above embodiments, the content that allows such design changes is indicated by labels such as "in the embodiment" or "in the embodiment," but this does not mean that design changes are not permitted for content without such labeling. Furthermore, the shaded lines marked on the cross-sections of the accompanying drawings are not intended to limit the material of the objects marked with shaded lines.

[0063] The following describes modified examples. In the accompanying drawings and descriptions of the modified examples, the same or equivalent components and parts are labeled with the same symbols as those in the embodiment. Descriptions that are repeated in the embodiment are omitted where appropriate, and the focus is on describing structures that differ from the embodiment.

[0064] In the description of the embodiments, an example of a so-called center crank type eccentric oscillating gear device is shown, but the present invention is not limited to this. For example, the gear device may also be a so-called distributed gear device, etc., in which multiple eccentric shafts are arranged at positions radially offset from the center.

[0065] In the description of the implementation, an example is given in which there are two eccentric bodies 12 and 13, but the number of eccentric bodies may also be one or more.

[0066] In the description of the implementation, an example of the oscillating gear 84 being an external gear 14 is shown, but the oscillating gear 84 may also be an internal gear.

[0067] In the description of the embodiments, examples of the power transmission component 82 being an input gear 28 and an example of the power transmission component 82 being a motor shaft 97 are shown, but the embodiments are not limited to these. Various known power transmission mechanisms such as pulleys can also be used as the power transmission component.

[0068] In the description of the embodiments, examples of the connecting part 44 being a threaded hole 412 and an example of the connecting part 44 being a spline are shown, but the embodiments are not limited to these. Various known mechanisms can also be used as the connecting part, such as a keyed connecting part.

[0069] In the description of the implementation, an example of flange member 86 being wheel frame 18 is shown, but it is not limited to this. The flange member may also be a member having functions other than wheel frame.

[0070] The above-described variations also perform the same functions and effects as the implementation method.

[0071] Any combination of the constituent elements and variations of the above embodiments is also effective as an embodiment of the present invention. New embodiments resulting from such combinations possess the effects of each of the combined embodiments and variations.

Claims

1. An eccentric oscillating gear device comprising an oscillating gear, a crankshaft having an eccentric body for oscillating and rotating the oscillating gear, an eccentric bearing disposed between the oscillating gear and the eccentric body, and a flange member disposed axially opposite to the crankshaft, characterized in that... The crankshaft has a hollow section. The flange component has a shaft component that is inserted into the hollow portion. An inner bearing is disposed between the inner circumference of the crankshaft and the outer circumference of the shaft component. The eccentric oscillating gear device also has a limiting component that is connected to the crankshaft and integrated with the crankshaft, and that restricts the eccentric bearing from moving axially. The limiting component has a connecting portion for connecting to a power transmission component that transmits power to the crankshaft. The inner bearing is axially positioned to overlap with the eccentric bearing. The limiting component is centered at the axial position where the inner bearing and the eccentric bearing overlap, and restricts the axial movement of the inner bearing and the eccentric bearing to the axially outward.

2. The gear device according to claim 1, characterized in that, The connecting part is a threaded hole for threaded fixing of the power transmission component.

3. The gear device according to claim 1, characterized in that, The connecting part is a spline disposed on the inner periphery of the limiting component.

4. The gear device according to any one of claims 1 to 3, characterized in that, The limiting component also restricts the axial movement of the inner bearing.

5. The gear device according to any one of claims 1 to 4, characterized in that, It also has an inner limiting member, which is fixed to the shaft member and restricts the crankshaft from moving axially.

6. The gear device according to claim 5, characterized in that, The limiting member has the hollow portion, and the inner limiting member is axially opposed to the inner bearing within the hollow portion.

7. An eccentric oscillating gear device comprising an oscillating gear, a crankshaft having an eccentric body for oscillating and rotating the oscillating gear, an eccentric bearing disposed between the oscillating gear and the eccentric body, and a flange member disposed axially opposite to the crankshaft, characterized in that... The crankshaft has a hollow section. The flange component has a shaft component that is inserted into the hollow portion. An inner bearing is disposed between the inner circumference of the crankshaft and the outer circumference of the shaft component. The eccentric oscillating gear device also has a limiting component integrated with the crankshaft that restricts the eccentric bearing from moving axially. The limiting component also restricts the inner bearing from moving axially. The inner bearing is axially positioned to overlap with the eccentric bearing. The limiting component is centered at the axial position where the inner bearing and the eccentric bearing overlap, and restricts the axial movement of the inner bearing and the eccentric bearing to the axially outward.

8. The gear device according to claim 7, characterized in that, The limiting component is the flange component.

9. The gear device according to claim 8, characterized in that, It also has a spacer member, which is axially held by the flange member, the eccentric bearing, and the inner bearing.

10. The gear device according to any one of claims 7 to 9, characterized in that, It also has an inner limiting member, which is fixed to the shaft member and restricts the crankshaft from moving axially.

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