JP7267550B2 - gearbox - Google Patents

Description

The present invention relates to a gear system.

In recent years, the use of gear devices is diversifying, and there are cases where there is a demand for their weight reduction. As a gear device that meets this demand, Patent Document 1 discloses a gear device in which an internal tooth member having an internal gear is made of a resin material.

JP 2018-155313 A

The inventor of the present invention has obtained the following new recognition after examining the technique of Patent Document 1. Resin-based materials are generally less rigid than metal materials. Therefore, when using an internal tooth member made of a resin-based material, the internal gear is more likely to deform radially outward due to meshing with the external gear than when using a metal material. As a result, it may become impossible to ensure normal meshing between the external gear and the internal gear. The technique of Patent Literature 1 is not devised from this point of view, and there is room for improvement.

SUMMARY OF THE INVENTION An aspect of the present invention has been made in view of such circumstances, and one of the objects thereof is to provide a gear device capable of ensuring normal meshing between an external gear and an internal gear while achieving weight reduction. .

An aspect of the present invention for solving the above-mentioned problems is a gear device. The gear device of this aspect is a gear device comprising an external gear and an internal tooth member provided with an internal gear that meshes with the external gear, wherein the internal tooth member is made of a resin-based material. and a reinforcing member for restraining radially outward deformation of the internal gear due to meshing with the external gear, wherein the reinforcing member is located on the inner teeth of the internal gear in the outer peripheral portion of the internal gear. provided at the outer periphery where the radial distance from the

A gear device according to another aspect of the present invention is a gear device comprising an external gear and an internal tooth member provided with an internal gear that meshes with the external gear, wherein the internal tooth member is made of resin. A reinforcing member made of a material for restricting radially outward deformation of the internal gear due to meshing with the external gear is provided, and the reinforcing member is made of a member separate from the bearing and the bolt.

ADVANTAGE OF THE INVENTION According to the aspect of this invention, normal mesh|engagement of an external gear and an internal gear can be ensured, achieving weight reduction.

1 is a side cross-sectional view of a gear device according to an embodiment; FIG. FIG. 2 is an enlarged view of FIG. 1;

An example of an embodiment of the present invention will be described below. The same reference numerals are given to the same components, and overlapping descriptions are omitted. In each drawing, for convenience of explanation, some of the components are omitted or the dimensions thereof are enlarged or reduced as appropriate. The drawings should be viewed according to the orientation of the symbols. The structures and shapes referred to in this specification include not only structures and shapes that exactly match the shapes referred to, but also structures and shapes that deviate due to errors such as dimensional errors and manufacturing errors.

Please refer to FIG. The gear device 10 of the embodiment mainly includes an input member 12 , an external gear 14 , an internal tooth member 16 , a casing 18 , a carrier 20 and an output member 22 . The internal gear member 16 is provided with an internal gear 24 that meshes with the external gear 14 . Hereinafter, the direction along the central axis La of the internal gear 24 is simply referred to as "axial direction X", and the circumferential direction and radial direction around the central axis La are simply referred to as "circumferential direction" and "radial direction".

The gear device 10 of the present embodiment is a flexural mesh type gear device that rotates the external gear 14 by moving the external gear 14 while flexurally deforming it with a vibrating body 26, which will be described later, and outputs the rotation component. The gear device 10 of the present embodiment is a so-called cylindrical flexural mesh gear device using a plurality of internal tooth members 16 .

The input member 12 is connected to a driving device (not shown), and rotation is input from the driving device. The drive device is, for example, a motor, gear motor, engine, or the like. The driving device is arranged on one side (right side in the drawing) of the input member 12 in the axial direction X. As shown in FIG. Hereinafter, for convenience of explanation, one side in the axial direction X will be referred to as the input side, and the other side (the left side in the drawing) will be referred to as the non-input side.

The input member 12 of this embodiment is configured by a so-called vibrating body 26 . The vibrating body 26 is a tubular member having sufficient rigidity to bend and deform the external gear 14 by its own rotation. The vibrating body 26 has an intermediate shaft portion 26a at an intermediate portion in the axial direction X. As shown in FIG. The outer peripheral shape of the cross section perpendicular to the axial direction X of the intermediate shaft portion 26a is elliptical. The term "ellipse" as used herein is not limited to geometrically strict ellipses, and includes substantially ellipses.

The external gear 14 is arranged on the outer peripheral side of the input member 12 and is rotatably supported by the input member 12 via a first bearing 28 arranged between the input member 12 and the external gear 14 . The external gear 14 of this embodiment is a flexible cylindrical member and is arranged on the outer peripheral side of the intermediate shaft portion 26 a of the vibrating body 26 .

The internal tooth member 16 is an annular member arranged on the outer peripheral side of the external gear 14, and the internal gear 24 is provided on the inner peripheral portion thereof. The internal gear 24 is composed of a plurality of internal teeth provided on the inner peripheral portion of the internal tooth member 16 over the entire circumference. The internal gear member 16 of this embodiment has a rigidity to the extent that it does not deform following the rotation of the vibrating body 26 . The internal toothed member 16 of the present embodiment includes a deceleration internal toothed member 16A (first internal toothed member) arranged on the input side and an output internal toothed member 16B (second internal toothed member) arranged on the opposite input side. member).

The deceleration internal tooth member 16A of this embodiment is fixed to an external member (not shown). A reduction internal gear 24A (first internal gear) that meshes with the external gear 14 is provided on the inner periphery of the reduction internal gear 16A. The speed reduction internal gear 24A has a number of teeth different from that of the external gear 14, and in this embodiment, has a number of teeth larger than that of the external gear 14. As shown in FIG. As a result, when the vibrating body 26 rotates once, a rotational phase shift occurs in the external gear 14 corresponding to the difference in the number of teeth between the internal gear 24A for reduction and the external gear 14, and the rotational phase corresponding to the shift is caused to rotate externally. occurs in the toothed gear 14. The reduction internal gear 24A causes the external gear 14 to rotate in conjunction with the rotation of the vibrating body 26 . The external gear 14 rotates at a rotational speed lower than that of the vibrating body 26 under a reduction ratio corresponding to the difference in the number of teeth between the reduction internal gear 24A and the external gear 14 .

An output internal gear 24B (second internal gear) that meshes with the external gear 14 is provided on the inner peripheral portion of the output internal gear 16B. The output internal gear 24B has the same number of teeth as the external gear 14 . As a result, when the external gear 14 rotates due to one rotation of the vibrating body 26, rotation of the same magnitude as the rotation component is output to the output internal tooth member 16B. When the external gear 14 rotates in association with the rotation of the vibrating body 26, the output internal gear 24B is synchronized with the rotation component.

The casing 18 is an annular member provided on the outermost periphery of the gear device 10 . The casing 18 of this embodiment is arranged radially outward with respect to the output internal gear 24B. A main bearing 30 is arranged between the casing 18 and the output internal gear 24B. The casing 18 of this embodiment rotatably supports the output internal gear 24B via the main bearing 30 . The casing 18 of the present embodiment is fitted and integrated with the reduction internal gear 24A using bolts or the like.

The main bearing 30 includes rolling elements 30a, an inner ring 30b, and an outer ring 30c. The rolling elements 30a of this embodiment are spherical bodies, but may be rollers or the like. In this embodiment, the inner ring 30b is made of a member different from the output internal tooth member 16B, and the outer ring 30c is made of a member different from the casing 18. As shown in FIG. The inner ring 30b may be configured by the output internal tooth member 16B, and the outer ring 30c may be configured by the casing 18.

The carrier 20 of this embodiment includes an input side carrier 20A arranged on the input side and a non-input side carrier 20B arranged on the non-input side. The input-side carrier 20A of the present embodiment is integrated with the reduction internal gear 24A by being connected to the reduction internal gear 24A using the first bolt B1. The non-input side carrier 20B of the present embodiment is integrated with the output internal gear 24B by being connected to the output internal gear 24B using the second bolt B2. A second bearing 32 is arranged between each carrier 20 and the input member 12 , and the carrier 20 rotatably supports the input member 12 via the second bearing 32 .

The output member 22 is integrated with the driven device by being connected to the driven device, and outputs rotational power to the driven device. The output member 22 of this embodiment is the anti-input side carrier 20B.

The operation of the above gear device 10 will be described.

When rotation is transmitted from the driving device to the input member 12 , the rotation is transmitted to the output member 22 via a reduction mechanism formed by the external gear 14 and the internal gear 24 . At this time, the rotation of the input member 12 is decelerated by the deceleration ratio of the deceleration mechanism and then output from the output member 22 to the driven device.

In this embodiment, the intermediate shaft portion 26a of the vibrating body 26 causes the external gear 14 to flex and deform into an elliptical shape via the first bearing 28 following the rotation of the vibrating body 26 (input member 12). . At this time, the external gear 14 is flexurally deformed so as to match the shape of the intermediate shaft portion 26 a of the vibrating body 26 while changing the meshing position with the internal gear 24 in the circumferential direction. As a result, the external gear 14 rotates with respect to the reduction internal gear 24A by an amount corresponding to the difference in the number of teeth between the external gear 14 and the reduction internal gear 24A each time the vibrator 26 rotates once. Relative rotation (rotation). At this time, the output internal gear 24B rotates in synchronization with the rotation component of the external gear 14 without changing the relative meshing position with respect to the external gear 14 before and after the input member 12 rotates once. The rotation of the output internal gear 24B is output from the non-input side carrier 20B (output member 22) to the driven device.

Please refer to FIG. The internal tooth member 16 described above is made of a resin-based material. In this embodiment, both the speed reduction internal tooth member 16A and the output internal tooth member 16B are made of a resin material. The term "resin-based material" as used herein includes not only engineering plastics and the like, but also fiber-reinforced resins such as carbon-fiber-reinforced resins and glass-fiber-reinforced resins, that is, composite materials. As a result, the weight of the internal tooth member 16 can be reduced as compared with the case where the internal tooth member 16 is made of a metallic material. The term “metallic material” as used herein includes iron-based materials including cast iron and steel, and aluminum-based materials including aluminum alloys.

The speed reduction internal tooth member 16A includes a first annular portion 34, a first projecting portion 36 projecting in the axial direction X from an inner peripheral end of the first annular portion 34, and an inner peripheral end of the first annular portion 34. A second protrusion 38 protruding in the axial direction X opposite to the first protrusion 36 is provided. Further, the speed reduction internal tooth member 16A has a third projecting portion 40 projecting in the axial direction X from the outer peripheral side end portion of the first annular portion 34 . The reduction internal gear 24A is provided on the inner circumference of the first annular portion 34 and the first protrusion 36 and the inner circumference of the base end of the second protrusion 38 . An annular recess 42 recessed in the axial direction X is provided between the first projecting portion 36 and the third projecting portion 40 in the internal gear member 16A for speed reduction. A first bolt B<b>1 that connects the speed reduction internal gear member 16</b>A and the input side carrier 20</b>A is screwed into the second projecting portion 38 .

The output internal tooth member 16B includes a second annular portion 44 having an inner peripheral portion provided with the output internal gear 24B, a fourth projecting portion 46 projecting in the axial direction X from the second annular portion 44, and a second annular portion. A fifth protrusion 48 protrudes from 44 in the axial direction X opposite to the fourth protrusion 46 . A second bolt B<b>2 that connects the output internal tooth member 16</b>B and the anti-input side carrier 20</b>B is screwed into the fourth projecting portion 46 . The fifth projecting portion 48 is arranged inside the annular recessed portion 42 of the internal gear reduction member 16A, and is provided at a position overlapping the first projecting portion 36 of the internal gear reduction member 16A when viewed from the radial direction.

The speed reduction internal tooth member 16A includes a first outer peripheral portion 50 formed by the first protrusion 36, a second outer peripheral portion 52 formed by the second protrusion 38, a first annular portion 34, and a third protrusion 40. and a third outer peripheral portion 54 to configure. The output internal tooth member 16B includes a fourth outer peripheral portion 56 formed by the second annular portion 44, the fourth projecting portion 46, and the proximal end portion of the fifth projecting portion 48, and the distal end portion of the fifth projecting portion 48. and a fifth outer peripheral portion 58 to configure. The term "peripheral portion" as used herein refers to a portion formed by the radially outwardly facing surface of the internal toothed member 16 being referred to. In the present embodiment, this “surface” is a flat surface extending in the axial direction X and is provided over the entire circumference of the internal gear member 16 around the center axis La.

The radial distances from the internal teeth 64 of the reduction internal gear 24A of the reduction internal gear 24A to the first outer peripheral portion 50, the second outer peripheral portion 52 and the third outer peripheral portion 54 are referred to as L1, L2 and L3. The radial distances from the internal teeth 66 of the output internal gear 24B of the output internal gear 24B to the fourth outer peripheral portion 56 and the fifth outer peripheral portion 58 are referred to as L4 and L5. This "radial distance" refers to the distance from the root of the internal tooth of the internal gear 24 being referred to to the radially outward facing surface formed by the outer peripheral portion being referred to. At this time, in the present embodiment, among the plurality of outer peripheral portions 50, 52, 54 of the internal gear member 16A for reduction, the radial distance L1 of the first outer peripheral portion 50 is the smallest, followed by the diameter of the second outer peripheral portion 52. The directional distance L2 is small, and the radial distance L3 of the third outer peripheral portion 54 is the largest. Further, in the present embodiment, among the plurality of outer peripheral portions 56 and 58 of the output internal gear 24B, the fourth outer peripheral portion 56 has the smallest radial distance L4, and the fifth outer peripheral portion 58 has the largest radial distance L5. growing.

A load directed radially outward is applied to the internal gear 24 due to meshing with the external gear 14, and the load attempts to deform such that the outer diameter partially increases. The gear device 10 includes a reinforcing member 60 that restrains radially outward deformation of the internal gear 24 due to meshing with the external gear 14 . The reinforcement member 60 of the present embodiment includes a first reinforcement member 60A that restrains deformation of the reduction internal gear 24A and a second reinforcement member 60B that restrains deformation of the output internal gear 24B.

The reinforcing member 60 is made of a material having a Young's modulus [Pa] greater than that of the resin-based material that forms the internal gear member 16 in which the reinforcing member 60 is used. In order to achieve this, the reinforcing member 60 of this embodiment is made of a metallic material. As a result, the deformation of the internal tooth member 16 can be restrained more effectively than using a resin-based material that constitutes the internal tooth member 16 . In relation to this effect, it is preferable that the Young's modulus of the reinforcing member 60 is as large as possible. The Young's modulus of the reinforcing member 60 is set, for example, to be ten times or more the Young's modulus of the resin-based material forming the internal tooth member 16 . This can be achieved, for example, by forming the internal gear member 16 from engineering plastic and forming the reinforcing member 60 from a metal-based material (for example, an iron-based material).

60 A of 1st reinforcement members are comprised by the member different from a bearing and a bolt. A “bearing” here is arranged between a plurality of components used in the gear device 10 that are capable of rotating relative to each other. In this embodiment, for example, the first bearing 28, the main bearing 30, and the like correspond. The “bolts” here are used to connect multiple components used in the gear device 10 . In this embodiment, for example, the first bolt B1 and the second bolt B2 correspond. The second reinforcing member 60B of this embodiment is composed of the inner ring 30b of the main bearing 30. As shown in FIG.

The first reinforcing member 60A has an endless ring shape. The second reinforcing member 60B has an endless ring shape. Here, the term "endless ring shape" refers to a shape that is continuous over the entire circumference around the central axis La and has no ends in the circumferential direction.

The first reinforcing member 60A is provided on the first outer peripheral portion 50 of the internal deceleration member 16A by being fitted to the first outer peripheral portion 50 thereof. The first reinforcing member 60A is provided in the first outer peripheral portion 50 having the smallest radial distance L1 among the outer peripheral portions 50, 52, and 54 of the internal deceleration member 16A in which the first reinforcing member 60A is used. become. The first reinforcing member 60A is fitted by interference fitting, intermediate fitting, or the like.

An annular groove 62 recessed in the axial direction X and extending in the circumferential direction is formed in the first annular portion 34 of the internal deceleration member 16A of this embodiment. .

The second reinforcing member 60B is fitted to the fourth outer peripheral portion 56 of the internal toothed member 16B for output so as to be provided on the fourth outer peripheral portion 56 thereof. The second reinforcing member 60B is provided on the fourth outer peripheral portion 56 having the smallest radial distance L4 among the outer peripheral portions 56 and 58 of the output internal tooth member 16B in which the second reinforcing member 60B is used. . The second reinforcing member 60B is fitted by interference fitting, intermediate fitting, or the like.

Effects of the gear device 10 described above will be described.

According to the gear device 10 of the present embodiment, when the internal gear 24 attempts to deform radially outward due to meshing with the external gear 14, the deformation can be restrained by the reinforcing member 60. Therefore, even when a resin-based material having a lower rigidity than a metal-based material is used for the internal gear member 16, normal meshing between the external gear 14 and the internal gear 24 is ensured compared to when the reinforcing member 60 is not provided. can. Therefore, by using a resin-based material for the internal gear member 16, it is possible to ensure normal meshing between the external gear 14 and the internal gear 24 while reducing the weight.

If the internal gear 24 is deformed radially outward, ratcheting (tooth skipping) is likely to occur between the internal gear 24 and the external gear 14 as the acting torque increases. In this respect, according to the present embodiment, the ratcheting can be suppressed by suppressing the radially outward deformation of the internal gear 24 . Therefore, by using a resin-based material for the internal tooth member 16, it is possible to increase the allowable torque of the gear device 10 while reducing the weight.

In addition, if normal meshing between the external gear 14 and the internal gear 24 cannot be ensured, it causes local wear. In this respect, according to the present embodiment, since the normal meshing between the external gear 14 and the internal gear 24 can be ensured, local wear can be suppressed.

The reinforcing member 60 is provided on the outer peripheral portions 50 and 56 of the inner tooth member 16 that are closest to the inner teeth of the internal gear 24 in the radial direction. Explain this advantage.

A boundary separating the reinforcing member 60 and the internal toothed member 16 in the radial direction is called a boundary position, and a case where a constant radially outward load is applied to the tooth contact position of the internal gear 24 against the external gear 14 is considered. In this case, the wider the radial range from the tooth contact position of the internal tooth member 16 to the boundary position, the more easily the amount of compressive deformation of the internal tooth member 16 increases in that radial direction range. becomes easier to change to

In this respect, according to the present embodiment, compared to the case where the reinforcing members 60 are provided on the outer peripheral portions 52, 54, 58 which are far from the internal teeth of the internal gear 24, The radial range to the boundary position can be narrowed. Accordingly, when a load is applied to the tooth contact position of the internal gear 24 with respect to the external gear 14, the amount of compressive deformation in the above-mentioned radial range can be reduced, and the external gear 14 and the internal gear 24 can be compressed. Normal meshing can be more secured.

The reinforcing member 60 has an endless ring shape. Therefore, compared to the case where the reinforcing member 60 has an end portion in the circumferential direction, the reinforcing member 60 can be made highly rigid, and the deformation of the internal tooth member 16 can be more easily restrained by the reinforcing member 60 .

If the reinforcing member 60 is made of a resin-based material, not only the internal toothed member 16 but also the reinforcing member 60 are affected by sink marks, making it difficult to ensure the dimensional accuracy of the reinforcing member 60 and the internal toothed member 16 . Due to this, when the reinforcing member 60 is fitted to the outer peripheral portion of the internal toothed member 16, a large gap is likely to occur between the internal toothed member 16 and the reinforcing member 60, and the deformation restraining effect of the reinforcing member 60 is reduced. It becomes difficult to get stable.

In this respect, according to the present embodiment, since the reinforcing member 60 is made of a metal material, it becomes easier to ensure the dimensional accuracy of the reinforcing member 60 compared to the case where the reinforcing member 60 is made of a resin material. As a result, when the reinforcing member 60 is fitted to the outer peripheral portion of the internal toothed member 16, a large gap is less likely to occur between the internal toothed member 16 and the reinforcing member 60, and the effect of restraining deformation by the reinforcing member 60 is stabilized. easier to obtain.

The reinforcing member 60 includes a first reinforcing member 60A that restrains deformation of the reduction internal gear member 16A that rotates the external gear 14. As shown in FIG. Explain this advantage.

The output internal gear 24B synchronizes with the rotation component of the external gear 14 . Therefore, ideally, the external teeth of the external gear 14 that mesh with the internal teeth of the output internal gear 24B are the same regardless of the number of revolutions of the vibrating body 26 . On the other hand, the reduction internal gear 24A rotates relative to the external gear 14 due to the rotation of the external gear 14 . Therefore, the external teeth of the external gear 14 that mesh with the internal teeth of the reduction internal gear 24 change according to the rotation speed of the vibrating body 26 . Since the dimensions of each external tooth of the external gear 14 change due to the influence of dimensional errors, when the meshing partner of each internal tooth of the internal gear 24 changes according to the rotation speed of the vibrating body 26, the external gear 14 The tooth contact position of each internal tooth may also change. As a result, the speed reduction internal gear 24A has a problem that local wear tends to occur on the tip side compared to the output internal gear 24B. According to the present embodiment, even under such a premise, deformation of the reduction internal gear 24A can be restrained by the first reinforcing member 60A, so local wear on the tip side thereof can be effectively suppressed. can be planned.

Next, another devised point of the reduction gear transmission of this embodiment will be described.

60 A of 1st reinforcement members are provided in the position which overlaps with the internal tooth 64 of the internal gear 24A for reduction|deceleration in which 60 A of 1st reinforcement members are used, seeing from a radial direction. In this embodiment, it is provided at a position overlapping with a part of the internal tooth 64 of the reduction internal gear 24A in the axial direction. Specifically, it is provided at a position overlapping a range including the axial center portion 64 a of the internal tooth 64 . In this embodiment, this range is equal to or more than half of the total axial length La of the internal teeth 64 .

The second reinforcing member 60B is provided at a position overlapping with the internal teeth 66 of the output internal gear 24B in which the second reinforcing member 60B is used when viewed from the radial direction. In this embodiment, it is provided at a position overlapping with a part of the internal teeth 66 of the output internal gear 24B in the axial direction. Specifically, it is provided at a position overlapping a range including the axial center portion 66 a of the internal tooth 66 . In this embodiment, this range is equal to or more than half of the total axial length Lb of the internal teeth 66 .

As a result, when a load is applied radially outward from the tooth contact position of the internal gear 24, the load is reduced compared to the case where the reinforcing member 60 is provided at a position that does not overlap the internal gear 24 when viewed from the radial direction. The reinforcing member 60 makes it easier to receive firmly. Accordingly, the radially outward deformation of the internal gear 24 can be effectively restrained by the reinforcing member 60 .

From the viewpoint of effectively obtaining such an effect, the reinforcing member 60 is positioned so as to overlap with the overall axial lengths La and Lb of the internal teeth 66 and 68 of the internal gear 24 in which the reinforcing member 60 is used, when viewed from the radial direction. Preferably provided.

A modification of each component will be described.

The specific example of the gear device 10 is not particularly limited as long as it includes the external gear 14 and the internal tooth member 16 that mesh with each other. For example, an eccentric oscillating gear device, a simple planetary gear device, or the like may be used in addition to the bending mesh type gear device. The eccentric oscillating gear device may be of a center crank type in which a crankshaft serving as the input member 12 is arranged on the center axis La of the internal gear 24 . In addition, a distributed type in which the crankshaft is arranged at a position offset from the central axis La may be used. The flexure mesh type gear device is not limited to a cylindrical type, and may be of a silk hat type, a cup type, or the like, for example.

Output member 22 may comprise either carrier 20 or casing 18 .

Materials of components other than the internal tooth member 16 among the components of the gear device 10 are not particularly limited. For example, the external gear 14 may be made of either a metal-based material or a resin-based material. The same applies to other constituent elements.

When a plurality of internal tooth members 16 are used, only one internal tooth member 16 may be made of a resin-based material, and the other internal tooth members 16 may be made of other materials. In this case, the gear device 10 may be provided with a reinforcing member 60 that restrains the deformation of the internal tooth member 16 made of a resin material. For example, the gear device 10 includes a first internal tooth member 16A made of a resin material, a second internal tooth member 16B made of a metal material, and a first reinforcing member 60A that restrains deformation of the first internal tooth member 16A. , the second reinforcing member 60B for restraining the deformation of the second internal tooth member 16B may not be provided. In addition, the gear device 10 includes a first internal tooth member 16A made of a metallic material, a second internal tooth member 16B made of a resin material, and a second reinforcing member 60B for restraining deformation of the second internal tooth member 16B. , and the first reinforcing member 60A for restraining the deformation of the first internal tooth member 16A may not be provided.

For example, the reinforcing member 60 is provided on the outer peripheral portion of the inner toothed member 16 in which the reinforcing member 60 is used, the outer peripheral portion having the smallest radial distance from the inner teeth of the inner toothed member 16 on the radially outer side. explained. In addition, it may be provided on the outer peripheral portion where the radial distance is the smallest radially inward with respect to the internal teeth of the internal tooth member 16 .

The reinforcing member 60 may be embedded inside the internal toothed member 16 if it is composed of a separate member from the bearing and bolt. Further, in this case, the reinforcing member 60 may be provided in the outer peripheral portion of the internal gear member 16 where the reinforcing member 60 is used, the outer peripheral portion having a larger radial distance. For example, the first reinforcing member 60A may be provided on the second outer peripheral portion 52 or the third outer peripheral portion 54 of the first internal toothed member 16A.

The reinforcing member 60 may have a shape having ends in the circumferential direction. This is based on the assumption that the reinforcing member 60 is configured with, for example, a C-shaped snap ring or the like. Further, the reinforcing member 60 may be composed of a plurality of split bodies obtained by splitting the ring shape in the circumferential direction.

The reinforcing member 60 is not limited to a metal-based material, and may be made of, for example, a resin-based material. In this case also, the reinforcing member 60 may be made of a material having a Young's modulus higher than that of the resin-based material forming the internal tooth member 16 in which the reinforcing member 60 is used. In this case, the reinforcing member 60 may be made of fiber-reinforced resin, which is formed by embedding fibers in the base of the same resin-based material as the internal gear member 16 . In this case, the portion in which the fibers are embedded becomes the reinforcing member 60 . The reinforcing member 60 is not limited to being configured by a member separate from the internal toothed member 16 , and may be configured as a part of the same member as the internal toothed member 16 .

When the reinforcing member 60 is fitted to the outer peripheral portion of the internal tooth member 16, the groove portion 62 may not be formed in the internal tooth member 16.

The reinforcing member 60 may be provided at a position that does not overlap the internal teeth of the internal gear 24 in which the reinforcing member 60 is used when viewed from the radial direction.

The embodiments and modifications of the present invention have been described in detail above. All of the above-described embodiments and modifications merely show specific examples for carrying out the present invention. The contents of the embodiments and modifications do not limit the technical scope of the present invention, and many design changes such as alterations, additions, and deletions of constituent elements are possible without departing from the spirit of the invention. In the above-described embodiment, the content that allows such design change is emphasized by adding the description of "embodiment", but the design change is permitted even in the content without such a description. Any combination of the above components is also effective as an aspect of the present invention. The hatching attached to the cross section of the drawing does not limit the material of the hatched object.

DESCRIPTION OF SYMBOLS 10... Gear apparatus, 14... External gear, 16... Internal tooth member, 24... Internal gear, 26... Vibrating body, 50, 52, 54, 56, 58... Outer peripheral part, 60... Reinforcing member.

Claims (4)

an external gear; and
a gear device comprising an internal tooth member provided with an internal gear that meshes with the external gear,
The internal tooth member is entirely made of a resin-based material, including a connecting portion to which another member is connected and an internal tooth portion,
a reinforcing member that restrains radially outward deformation of the internal gear due to meshing with the external gear;
A gear device in which the reinforcing member is configured by a bearing provided in an outer peripheral portion of the inner tooth member, the outer peripheral portion having the smallest radial distance from the inner teeth of the internal gear. 2. The gear device according to claim 1 , wherein the reinforcing member is fitted around the outer peripheral portion of the internal tooth member and is made of a metallic material. The gear unit according to claim 1 or 2 , wherein the reinforcing member is provided at a position overlapping the internal teeth of the internal gear when viewed from the radial direction. A vibrating body that flexurally deforms the external gear,
The internal tooth member includes:
a first internal tooth member provided with a first internal gear that rotates the external gear;
a second internal tooth member provided with a second internal gear that synchronizes with the rotation component of the external gear,
The reinforcing member includes a first reinforcing member that constrains radially outward deformation of the first internal gear, and the bearing that constrains radially outward deformation of the second internal gear. 4. The gear device according to any one of claims 1 to 3 , further comprising a second reinforcing member.

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