WO2020031891A1 - Planetary gear device - Google Patents

Abstract

The present invention provides a planetary gear device wherein power transmission is carried out efficiently. This planetary gear device (1) is provided with: a first internally toothed gear (20) and a second internally toothed gear (30); a first externally toothed gear (13a) which engages with the first internally toothed gear (20); a second externally toothed gear (13b) which engages with the second internally toothed gear (30); and an eccentric body (10A) which is orbited by the first externally toothed gear (13a) and the second externally toothed gear (13b). The first externally toothed gear (13a) and the second externally toothed gear (13b) rotate integrally with each other; the first internally toothed gear (20) and the second internally toothed gear (30) respectively have supporting bodies (51a, 51b, 21, 34, 35, 31, 39) and a plurality of inner teeth (21, 22, 31, 32); and each one of the plurality of inner teeth (21, 22, 31, 32) comprises a rotor (22, 32) which is supported by a supporting body in a rotatable manner.

Description

Planetary gear set

The present invention relates to a planetary gear device.

FIG. 1 of Patent Literature 1 discloses a first external gear and a second external gear that perform orbital movement by an eccentric body provided on an input shaft, and a first internal gear and a second internal gear that individually mesh with the first external gear and the second external gear. A planetary gear set with gears is shown. The first external gear and the second external gear are connected planetary gears that rotate integrally, the first internal gear is fixed to a casing, and the second internal gear is connected to an output shaft. I have.

With this configuration, the rotational motion input to the input shaft is reduced by the gear mechanism of the first external gear and the first internal gear and the gear mechanism of the second external gear and the second internal gear. The decelerated rotational motion is transmitted to the output shaft.

Japanese Utility Model Publication No. 59-171248

は In the above planetary gear device, an involute gear or the like is used for each gear. Therefore, slippage occurs between the teeth of the first external gear and the first internal gear that mesh with each other and between the teeth of the second external gear and the second internal gear that mesh with each other, and the power transmission efficiency There is a problem that the decrease is easily caused. Furthermore, there is a problem that tooth wear is likely to occur due to tooth slippage.

An object of the present invention is to provide a planetary gear device capable of efficiently transmitting power.

The present invention
A first internal gear and a second internal gear,
A first external gear that meshes with the first internal gear;
A second external gear that meshes with the second internal gear;
An eccentric body for orbiting the first external gear and the second external gear;
With
The first external gear and the second external gear rotate integrally,
Each of the first internal gear and the second internal gear has a support and a plurality of internal teeth, and each of the plurality of internal teeth includes a rotating body rotatably supported by the support. ,
It is a planetary gear device.

According to the present invention, a planetary gear device capable of efficiently transmitting power can be provided.

It is a sectional view showing the planetary gear device concerning Embodiment 1 of the present invention. It is the figure which looked at the planetary gear device of Embodiment 1-Embodiment 9 from the axial direction. FIG. 2 is a sectional view taken along line BB of the planetary gear device of FIG. 1. FIG. 2 is a sectional view taken along line CC of the planetary gear device of FIG. 1. It is DD sectional drawing of the planetary gear apparatus of FIG. FIG. 2 is a perspective view showing a configuration in which a first external gear, a rotating body of a first internal gear, a second external gear and a rotating body of a second internal gear are combined. It is a sectional view showing a planetary gear device concerning Embodiment 2 of the present invention. It is a sectional view showing a planetary gear device concerning Embodiment 3 of the present invention. It is a sectional view showing a planetary gear device concerning Embodiment 4 of the present invention. FIG. 10 is a plan view of a portion of a second support member of the planetary gear device of FIG. 9 as viewed from a non-output side. It is a sectional view showing a planetary gear device concerning Embodiment 5 of the present invention. It is a sectional view showing a planetary gear device concerning Embodiment 6 of the present invention. It is sectional drawing which shows the planetary gear apparatus which concerns on Embodiment 7 of this invention. It is sectional drawing which shows the planetary gear apparatus which concerns on Embodiment 8 of this invention. FIG. 15 is a sectional view taken along line EE of the planetary gear device of FIG. 14. It is sectional drawing which shows the location of the rotating body of the 2nd internal gear in the planetary gear device which concerns on Embodiment 9 of this invention. It is a figure showing an example of an industrial robot to which the planetary gear device of Embodiment 9 is applied.

Hereinafter, each embodiment of the present invention will be described in detail with reference to the drawings. In this specification, a direction along the rotation axis O1 is called an axial direction, a direction perpendicular to the rotation axis O1 is called a radial direction, and a rotation direction about the rotation axis O1 is called a circumferential direction.

(Embodiment 1)
FIG. 1 is a sectional view showing a planetary gear device according to Embodiment 1 of the present invention. FIG. 1 shows a cross section taken along line AA of FIG. FIG. 2 is a view of the planetary gear device 1 of FIG. 1 as viewed from an axial direction. FIG. 3 is a sectional view taken along line BB of the planetary gear device of FIG. FIG. 4 is a cross-sectional view taken along line CC of the planetary gear device of FIG. FIG. 5 is a sectional view taken along line DD of the planetary gear device of FIG. FIG. 6 is a perspective view showing a configuration in which the first external gear, the rotating body of the first internal gear, the second external gear and the rotating body of the second internal gear are combined. FIG. 6 shows a simplified configuration in which the number of teeth of each gear is reduced. FIG. 2 also corresponds to a view of the planetary gear devices 1A to 1H of Embodiments 2 to 9 as viewed from the axial direction.

The planetary gear device 1 according to the first embodiment is a device that reduces the rotational motion input from the motor or the like (not shown) to the input shaft 10 and outputs the rotational motion from the output member 52. The planetary gear device 1 includes an input shaft 10 having an eccentric body 10A, an external gear member 13 provided with a first external gear 13a and a second external gear 13b, a counterweight 18, and a first internal gear. 20 and a second internal gear 30. Further, the planetary gear device 1 includes a fixed member 51 connected to the first internal gear 20, an output member 52 connected to the second internal gear 30, a casing 53, a main bearing 46, a first input bearing 41, A two-input bearing 42, a first eccentric bearing 43, and a second eccentric bearing 44 are provided.

The input shaft 10 has shaft portions 10B and 10C centered on the rotation axis O1, and an eccentric body 10A eccentric from the rotation axis O1. As shown in FIG. 3, the eccentric body 10A has an outer peripheral surface having a circular cross section centered on the eccentric axis O2. The shaft portions 10B and 10C are located at one and the other in the axial direction of the eccentric body 10A. The input shaft 10 rotates around a rotation axis O1.

As shown in FIG. 5, the first external gear 13a includes a plurality of external teeth having a cross section perpendicular to the rotation axis O1 having an epitrochoid parallel curve. The tooth length of the first external gear 13a is set to be approximately twice or slightly larger than the eccentric amount of the eccentric body 10A.

As shown in FIG. 3, the second external gear 13b also includes a plurality of external teeth having a cross-sectional shape perpendicular to the rotation axis O1 and having an epitrochoid parallel curve. The tooth length of the second external gear 13b is set to be approximately twice the amount of eccentricity of the eccentric body 10A or slightly larger.

The first external gear 13a and the second external gear 13b are arranged at intervals in the axial direction, and are integrally provided by a single member. That is, the first external gear 13a and the second external gear 13b are provided on one and the other in the axial direction of the external gear member 13 which is a single member. An intermediate portion 13c having a smaller diameter than the pitch circle is provided between the first external gear 13a and the second external gear 13b of the external gear member 13. The first external gear 13a, the second external gear 13b, and the intermediate portion 13c may be provided on separate members and connected to each other.

１ The first external gear 13a and the second external gear 13b have different numbers of teeth, and the first external gear 13a and the second external gear 13b rotate integrally. Note that the first external gear 13a and the second external gear 13b may have the same number of teeth.

The external gear member 13 has a through hole penetrating in the axial direction, and the first eccentric body bearing 43 and the second eccentric body bearing 44 are fitted inside the through hole. The first eccentric bearing 43 is located radially inward of the first external gear 13a, and the second eccentric bearing 44 is radially inward of the second external gear 13b. The eccentric body 10A of the input shaft 10 is fitted inside the first eccentric body bearing 43 and inside the second eccentric body bearing 44. The eccentric axis O2, the central axis of the pitch circle of the first external gear 13a, and the central axis of the pitch circle of the second external gear 13b are common.

The first internal gear 20 meshes with the first external gear 13a. The first internal gear 20 includes a plurality of support pins 21, a plurality of rotating bodies 22, and a first support portion 51a and a second support portion 51b that support the plurality of support pins 21. The first support portion 51a and the second support portion 51b are a part of the fixing member 51, and are integrally formed by a single member. The first support 51a and the second support 51b may be provided separately and connected to each other. The first support 51a may be referred to as a first support member, and the second support 51b may be referred to as a first support. You may call it a 2nd support member. The first support 51a, the second support 51b, and the plurality of support pins 21 correspond to a support that supports the plurality of rotating bodies 22 in the first internal gear 20 (may be referred to as a first support).

The plurality of support pins 21 and the plurality of rotating bodies 22 constitute a plurality of internal teeth. The rotating body 22 has a cylindrical shape. The plurality of rotating bodies 22 are rotatably fitted to the plurality of support pins 21 via bearings (for example, needle bearings), and come into contact with (engage with) the external teeth of the first external gear 13a.

The first support portion 51a has an annular (ring-shaped) form having a through hole radially inward, and the shaft portion 10B of the input shaft 10 is fitted into the through hole via the first input bearing 41. . The first support portion 51a supports the plurality of support pins 21 in the same pitch circle and arranged at equal intervals in the circumferential direction, for example. Specifically, the first support portion 51a has a plurality of pin holes through which the plurality of support pins 21 pass, and one ends of the plurality of support pins 21 in the axial direction are tightly fitted into the pin holes. When the planetary gear device 1 is incorporated in the device, the first support portion 51a is fixed to the base member or the like in the device integrally with the fixing member 51 (connected to the fixed side).

The second support portion 51b has an annular shape having a through hole radially inward, and the intermediate portion 13c of the external gear member 13 and the input shaft 10 are arranged inside the through hole. Similarly to the first support portion 51a, the second support portion 51b supports the plurality of support pins 21 on the same pitch circle and arranged at equal intervals in the circumferential direction. Specifically, the second support portion 51b has a plurality of pin holes through which the plurality of support pins 21 are respectively passed, and the other ends of the plurality of support pins 21 in the axial direction are tightly fitted into the pin holes. As shown in FIG. 5, the second support portion 51b has a through hole H51 provided with peaks and troughs so as to pass through the first external gear 13a. Specifically, the inner diameter of the ridge of the through hole H51 is smaller than the tip diameter of the first external gear 13a and larger than the root diameter. The inside diameter of the valley (recess) of the through hole H51 is larger than the tip diameter of the first external gear 13a. Thereby, while suppressing an increase in the radial dimension of the device, the first external gear 13a is placed in a state where the tooth tip of the first external gear 13a is located at the valley and the tooth bottom is located at the peak. It can be moved in the axial direction and easily assembled inside the first internal gear 20. When the planetary gear device 1 is incorporated in the device, the second support portion 51b is fixed to a base member or the like in the device integrally with the fixing member 51.

A flange portion 21a that protrudes in the radial direction of each support pin 21 is provided at one axial end (opposite output side) of the plurality of support pins 21, and the other axial end (output) of each support pin 21 is provided. Side), a retaining ring (E-ring, C-ring, etc.) 21b is attached. The “output side” means a side on which the output member 52 is arranged in the axial direction, and the “non-output side” means a side opposite to the output side in the axial direction. The flange portion 21a and the retaining ring 21b function as a "prevention mechanism" for preventing the support pins 21 from coming out of the pin holes of the first support portion 51a and the second support portion 51b.

滑 り The sliding member 24 is provided between the first support portion 51a and each rotating body 22. Similarly, a sliding member 25 is provided between the second support portion 51b and each rotating body 22. The sliding members 24 and 25 have a washer shape, and the positions thereof are regulated by passing the support pins 21 therethrough. The sliding members 24 and 25 have a surface with a smaller coefficient of friction than the rotating body 22, and prevent the rotating body 22 from directly rubbing against the first support portion 51a or the second support portion 51b, thereby suppressing wear of these members. I do.

The second internal gear 30 meshes with the second external gear 13b. The second internal gear 30 includes a plurality of support pins 31, a plurality of rotating bodies 32, a first support member 34 and a second support member 35 that support the plurality of support pins 31, and a plurality of auxiliary pins 39. Have. The first support member 34, the second support member 35, the plurality of support pins 31, and the plurality of auxiliary pins 39 are configured to support a plurality of rotating bodies 32 in the second internal gear 30 (also referred to as a first support body). Good).

The plurality of support pins 31 and the plurality of rotating bodies 32 form a plurality of internal teeth. The rotating body 32 has a cylindrical shape. The plurality of rotating bodies 32 are rotatably fitted to the plurality of support pins 31 via bearings (for example, needle bearings), and come into contact with (engage with) the external teeth of the second external gear 13b.

The first support member 34 has an annular shape having a through hole in which the input shaft 10 and the second input bearing 42 are arranged radially inward. The first support member 34 supports the plurality of support pins 31 in the same pitch circle and arranged at equal intervals in the circumferential direction. Specifically, the first support member 34 has a plurality of pin holes through which the plurality of support pins 31 pass, and one ends of the plurality of support pins 31 in the axial direction are tightly fitted into the pin holes. The first support member 34 is connected to the output member 52 (output side), and is rotatably supported by the fixing member 51 and the casing 53.

The second support member 35 has a circular and disk-like shape having a through hole in which the input shaft 10 and the intermediate portion 13c of the external gear member 13 are arranged radially inward. Similarly to the first support member 34, the second support member 35 supports the plurality of support pins 31 in an arrangement arranged at equal intervals in the circumferential direction. Specifically, the second support member 35 has a plurality of pin holes through which the plurality of support pins 31 pass, and the other end side of the plurality of support pins 31 in the axial direction (the opposite side of the first support member 34). The pin hole is tightly fitted. As shown in FIG. 4, the second support member 35 has a central through-hole H35 provided with a valley so as to pass through the second external gear 13b. Specifically, the inner diameter of the peak of the through hole H35 is smaller than the tip diameter of the second external gear 13b and larger than the root diameter. The inside diameter of the trough (recess) of the through hole H35 is larger than the tip diameter of the second external gear 13b. Thereby, while suppressing an increase in the radial dimension of the device, the second external gear 13b is placed in a state where the tip of the second external gear 13b is located at the valley and the tooth bottom is located at the peak. It can be moved in the axial direction and easily incorporated inside the second internal gear 30. The second support member 35 is disposed between the intermediate portion 13c of the external gear member 13 and the casing 53 at an interval therefrom.

A flange portion 31b is provided at one end (non-output side) in the axial direction of each support pin 31 so as to protrude in the radial direction of the support pin 31, and is provided at the other end (output side) of each support pin 31 in the axial direction. Is provided with a retaining ring (E ring, C ring, etc.) 31a. The flange portion 31b and the retaining ring 31a function as a "prevention mechanism" for preventing the support pins 31 from coming out of the pin holes of the first support member 34 and the second support member 35.

滑 り A sliding member 36 is provided between the first support member 34 and each rotating body 32. A sliding member 37 is provided between the second support member 35 and each rotating body 32. The sliding members 36 and 37 have a washer shape, and the positions of the sliding members 36 and 37 are regulated by passing the respective support pins 31. The sliding members 36 and 37 have a smaller coefficient of friction on the surface than the rotating body 32, and prevent the rotating body 32 from directly rubbing against the first support member 34 or the second support member 35, thereby suppressing wear of these members. I do.

The plurality of auxiliary pins 39 are provided at positions different from the plurality of support pins 31 in the circumferential direction. Specifically, the auxiliary pin 39 is provided between the support pins 31 in the circumferential direction. The pitch circle diameter of the auxiliary pins 39 is larger than the pitch circle diameter of the support pins 31. The first support member 34 and the second support member 35 have a plurality of pin holes through which one end and the other end of the plurality of auxiliary pins 39 pass. The plurality of auxiliary pins 39 are connected to the pin holes of the first support member 34 and the pin holes of the second support member 35 by, for example, an interference fit. By connecting the plurality of auxiliary pins 39, the second support member 35 and the first support member 34 are more firmly connected. Note that the auxiliary pin 39 does not function as an internal tooth (does not constitute an internal tooth).

The fixing member 51 has an annular shape having a through-hole in which the first input bearing 41 and the input shaft 10 are arranged radially inward, and is arranged on the opposite output side of the planetary gear device 1. The fixing member 51 covers the outside of the first internal gear 20 in the radial direction. The fixing member 51 is connected to a base member or the like in the device in which the planetary gear device 1 is incorporated, for example. Thereby, the planetary gear device 1 is supported by the base member.

The casing 53 has a cylindrical shape, is connected to the fixing member 51, and covers the radially outer side of the second internal gear 30.

The output member 52 has an annular shape having a through hole through which the input shaft 10 passes radially inward, and is arranged on the output side of the planetary gear device 1. The first support member 34 of the second internal gear 30 is connected to the output member 52. Furthermore, the output member 52 is connected to a driven member, for example, in a system in which the planetary gear set 1 is incorporated.

The first eccentric bearing 43 is disposed between the first external gear 13a and the eccentric 10A. The second eccentric bearing 44 is arranged between the second external gear 13b and the eccentric 10A. The external gear member 13 is supported by the eccentric body 10A via the first eccentric body bearing 43 and the second eccentric body bearing 44 in a rotatable state about the eccentric shaft O2.

The first eccentric bearing 43 and the second eccentric bearing 44 are angular bearings (specifically, angular ball bearings) and are arranged back to back. The first eccentric bearing 43 and the second eccentric bearing 44 are not limited to angular ball bearings, but may be any angular bearing. The angular bearing means a bearing in which a rolling surface (also referred to as a raceway surface) on which a rolling element rolls faces in a direction inclined from the radial direction, and includes a tapered roller bearing. An angular bearing can also be described as a bearing in which the line of action of the bearing is inclined with respect to the axial direction and the radial direction. Preload is applied to the first eccentric bearing 43 and the second eccentric bearing 44 in a direction in which the outer rings move away from each other and in a direction in which the inner rings move closer to each other.

The second input bearing 42 is disposed between the shaft portion 10C of the input shaft 10 and the first support member 34 of the second internal gear 30. The first input bearing 41 is disposed between the shaft portion 10B of the input shaft 10 and the fixing member 51. The input shaft 10 is rotatably supported by the fixed member 51 and the first support member 34 via the first input bearing 41 and the second input bearing 42.

The first input bearing 41 and the second input bearing 42 are angular bearings (specifically, angular ball bearings), and are arranged face to face. The first input bearing 41 and the second input bearing 42 are not limited to angular ball bearings, but may be any angular bearing. Preload is applied to the first input bearing 41 and the second input bearing 42 in a direction in which the outer rings approach each other and in a direction in which the inner rings move away from each other. The first input bearing 41 and the second input bearing 42 are not limited to angular bearings, and various types of bearings can be used. For example, ordinary ball bearings may be used.

The main bearing 46 is arranged between the casing 53 connected to the fixing member 51 and the first support member 34 connected to the output member 52. The output member 52 and the second internal gear 30 are rotatably supported by the fixed member 51 and the casing 53 via the main bearing 46. The main bearing 46 is disposed so as to overlap with the support pins 21 and 31 of the first internal gear 20 and the second internal gear 30 when viewed from the axial direction, and the second input bearing 42 when viewed from the radial direction. Are arranged on the output side with respect to the center.

The counterweight 18 is fixed to the input shaft 10 in a range opposite to the eccentric side of the eccentric body 10A. In the present embodiment, the counter weight 18 is installed in a range of ± 90 degrees around the anti-eccentric direction, but is not limited to this, and may be installed in a predetermined range including the anti-eccentric direction. The counterweight 18 is a weight for balancing the eccentric body 10A, the first eccentric body bearing 43, the second eccentric body bearing 44, and the external gear member 13 which rotate eccentrically from the rotation axis O1. The counterweight 18 is disposed between the first eccentric body bearing 43 and the second eccentric body bearing 44 and between the intermediate portion 13c of the external gear member 13 and the input shaft 10. The counter weight 18 suppresses vibration and the like caused by the eccentric member rotating.

<Operation description>
As shown in FIG. 6, the first external gear 13a and the second external gear 13b are, on the eccentric side, the internal teeth (22) of the first internal gear 20 and the internal teeth of the second internal gear 30. Meshes with (32). That is, on the eccentric side, the rotating bodies 22 and 32 are located between the valleys of the external teeth. When a rotational motion is input to the input shaft 10 from a motor or the like (not shown), the eccentric body 10A rotates, and the eccentric shaft O2 moves around the rotation shaft O1. Since the central axis of the external gear member 13 is common to the eccentric shaft O2, the external gear member 13 circulates (oscillates) similarly to the eccentric shaft O2, and the first external gear 13a and the second external teeth. The meshing position of the gear 13b with the first internal gear 20 and the second internal gear 30 similarly moves orbitally.

When the input shaft 10 makes one rotation and the meshing position between the first external gear 13a and the first internal gear 20 makes one revolution in the circumferential direction, the first external gear 13a and the first internal gear 20 Due to the difference in the number of teeth, the meshing teeth of the first external gear 13a and the first internal gear 20 shift. Since the first internal gear 20 is connected to the fixed member 51 and does not rotate, the displacement of the meshing teeth appears as a rotational motion (rotation) about the rotation axis O1 of the first external gear 13a. For example, if the first external gear 13a has 13 teeth and the first internal gear 20 has 14 teeth, each time the input shaft 10 rotates once, the first external gear 13a rotates by one tooth for the rotation shaft O1. Rotate (rotate) around. When the number of rotations of the first external gear 13a is equal to the number of teeth, the rotation becomes one rotation. Therefore, the reduction ratio A of the rotation of the first external gear 13a with respect to the rotation of the input shaft 10 is ｛(the number of teeth of the first external gear 13a− The number of teeth of the first internal gear 20) / the number of teeth of the first external gear 13a. For example, if the first external gear 13a has 13 teeth and the first internal gear 20 has 14 teeth, the speed is reduced to -1/13. Here, the rotation direction of the input shaft 10 is represented by a positive number.

Also at the meshing portion between the second external gear 13b and the second internal gear 30, the input shaft 10 makes one rotation, and the meshing position between the second external gear 13b and the second internal gear 30 moves in the circumferential direction. After one revolution, the teeth meshing with each other shift. On the other hand, in this meshing portion, the teeth meshing with each other are shifted while both the second external gear 13b and the second internal gear 30 rotate about the rotation axis O1. For this reason, between the time when any one tooth of the second external gear 13b is most eccentric and the time when this tooth is next most eccentric, the second external gear 13b and the second internal gear 30 The meshing teeth are shifted from each other by the difference in the number of teeth. For example, if the second external gear 13b has 12 teeth and the second internal gear 30 has 13 teeth, the teeth meshing with each other shift by one tooth during the above period. Then, the rotation of the external gear member 13 about the rotation axis O1 is added to the rotation corresponding to the displacement of the meshing teeth, and the second internal gear 30 rotates.

場合 When the reduction ratio A of the first stage is negative (the rotation direction of the first external gear 13a is opposite to the rotation direction of the input shaft 10), the reduction ratio B of the second stage can be calculated as follows. While the first external gear 13a makes one rotation around the rotation axis O1, the number N of times that any tooth of the second external gear 13b is most eccentric is the number of rotations of the input shaft 10 during that time + the second The rotation speed of the external gear 13b (the rotation speed when the rotation direction of the input shaft 10 is negative). That is, when the reduction ratio A is negative, N = − (1 / reduction ratio A) +1. Then, during this time, the meshing teeth of the second internal gear 30 and the second external gear 13b are shifted by (N × difference in the number of teeth). The deviation is a delay amount or advance amount from the amount (one time point) in which the second external gear 13b rotates about the rotation axis O1 during this period. If the number of teeth of the second internal gear 30 is larger than the number of teeth of the second external gear 13b, the amount of delay is set, and if the number is small, the amount of advance is set. Accordingly, the reduction ratio B of the rotation of the second internal gear 30 with respect to the rotation of the first external gear 13a is 1− ｛N × (the number of teeth of the second internal gear 30−the number of teeth of the second external gear 13b). ) / The number of teeth of the second internal gear 30. For example, if the reduction ratio A is -1/13 as in the above-described example, the second external gear 13b has 12 teeth, and the second internal gear 30 has 13 teeth, the reduction ratio B becomes -1/13. It becomes 13. Here, the rotation direction input to the first external gear 13a is represented by a positive number. When the reduction ratio A is positive, the same expression is used, although details are omitted.

As a result, the planetary gear device 1 can obtain a motion of total reduction ratio = reduction ratio A × reduction ratio B. That is, the rotational motion of the input shaft 10 is reduced by the reduction ratio A × the reduction ratio B and output to the output member 52. The total reduction ratio is, for example, the number of teeth of each of the first external gear 13a, the first internal gear 20, the second external gear 13b, and the second internal gear 30 is {9, 10, 6, 7}. If the number of teeth is {11, 12, 8, 9}, it is 1/23. The total reduction ratio is 1/78 if the number of teeth is {13, 14, 11, 12}, and if the number of teeth is {13, 14, 12, 13} as in the example described above. For example, it becomes 1/169. As described above, the reduction ratio can be largely changed by the combination of the number of teeth. Further, the reduction ratio can be set in a fine width by a combination of the number of teeth.

<Effect of Embodiment 1>
As described above, according to the planetary gear device 1 of the first embodiment, the first internal gear 20 and the second internal gear 30 have a plurality of rotation pins rotatably supported by the plurality of support pins 21 and 31, respectively. It has bodies 22,32. When the first internal gear 20 meshes with the first external gear 13a, the plurality of rotating bodies 22 roll on the outer peripheral surface of the first external gear 13a. Similarly, when the second internal gear 30 meshes with the second external gear 13b, the plurality of rotating bodies 32 roll on the outer peripheral surface of the second external gear 13b. Therefore, the rotational motion can be decelerated with high efficiency by the non-slip engagement between the external teeth and the internal teeth, and the decelerated rotational motion can be output.

By the way, in the structure of the planetary gear device 1 of the first embodiment, the first external gear 13a, the second external gear 13b, and the support are provided radially outward of the first eccentric bearing 43 and the second eccentric bearing 44. Components such as pins 21 and 31 and rotating bodies 22 and 32 are arranged. Therefore, in order to suppress an increase in the radial dimension of the planetary gear device 1, the first eccentric bearing 43 and the second eccentric bearing 44 need to be downsized. However, simply reducing the size of the bearing reduces the bearing load capacity of the bearing.

Therefore, according to the planetary gear device 1 of the first embodiment, the first eccentric body bearing 43 and the second eccentric body bearing 44 employ an angular bearing, and these are arranged back to back. By arranging the angular bearings back-to-back, these load action lines extend from the bearings toward the bearing center axis, and the distance between the points of application of the bearings can be increased. Can be increased. Furthermore, by making the angular bearing back-to-back, it is possible to receive axial loads in both directions, and in addition to applying a preload, the rigidity of the bearing portion can be increased.

Further, according to the planetary gear device 1 of the first embodiment, the first eccentric body bearing 43 and the second eccentricity are provided between the first input bearing 41 and the second input bearing 42, which are angular bearings arranged face to face. A body bearing 44 is arranged. With this configuration, the allowable moment load of the planetary gear device 1 can be further increased.

<Effect of Embodiment 2>
By the way, if the support structure of the support pins 21 and 31 is a cantilever support, it is difficult to secure the strength of the support pins 21 and 31. In particular, when the size of the planetary gear device 1 is reduced, the diameter of the support pins 21 and 31 is also required to be reduced, so that it is more difficult to secure the strength of the support pins 21 and 31. Further, the support pins 21 and 31 repeatedly receive a radial load from the first external gear 13a and the second external gear 13b. For this reason, for example, when the support pins 21 and 31 are connected by interference fit, there is a problem that the support pins 21 and 31 are likely to be minutely displaced at the connection location.

However, according to the planetary gear device 1 of the first embodiment, both ends of the support pin 21 are supported by the first support portion 51a and the second support portion 51b. Thereby, it is easy to secure the strength of the support pin 21. As a result, it is possible to reduce the diameter of the support pin 21 and reduce the size of the planetary gear device 1. Further, the rigidity of the configuration combining the support pin 21, the first support portion 51a, and the second support portion 51b is improved, and even when the support pin 21 is repeatedly subjected to a load, the support pin 21 is slightly displaced at the connecting portion. Can be suppressed.

According to the planetary gear device 1 of the first embodiment, both ends of the support pin 31 are supported by the first support member 34 and the second support member 35. Thereby, it is easy to secure the strength of the support pin 31. Of the plurality of support pins 31 and the plurality of rotating bodies 32, the load is directly applied only to a part of the range that meshes with the second external gear 13b. For this reason, the presence of the second support member 35 allows the load applied to a part of the range to be distributed and received by the support pins 31 in the entire range, thereby reducing the load carried by each support pin 31. . As a result, the diameter of the support pin 31 can be reduced, and the planetary gear device 1 can be downsized. Further, the rigidity of the configuration in which the support pin 31, the first support member 34, and the second support member 35 are combined is improved, and even when the support pin 31 is repeatedly subjected to a load, the support pin 31 is slightly displaced at the connection position. Can be suppressed.

Furthermore, according to the planetary gear device 1 of the first embodiment, the auxiliary pin 39 is provided between the pair of circumferentially adjacent support pins 31, and the auxiliary pin 39 is connected to the first support member 34 and the second support member 35. It is connected to. Thereby, the rigidity of the configuration for supporting the support pins 31 is further improved, and the strength of the support pins 31 is more easily secured. In addition, it is possible to further suppress the support pin 31 from being minutely displaced at the connection position.

Further, according to the planetary gear device 1 of the first embodiment, the second internal gear 30 connected to the output member 52 (output side) has the auxiliary pin 39 and is connected to the fixed member 51 (fixed side). The first internal gear 20 has no auxiliary pin. Thereby, the rigidity can be added by the auxiliary pin 39 for the support configuration of the output-side support pin 31 where it is difficult to obtain rigidity. On the other hand, with regard to the support configuration of the fixed-side support pins 21 that can easily obtain rigidity, the number of parts, the number of assembly steps, and the weight can be reduced by omitting the auxiliary pins.

According to the planetary gear device 1 of the first embodiment, the second support portion 51b that supports one end of the support pin 21 has the through hole H51 (FIG. 5) through which the first external gear 13a passes. Thereby, the first external gear 13a can be easily incorporated inside the first internal gear 20 while suppressing an increase in the radial dimension of the device. The second support member 35 supporting one end of the support pin 31 has a through hole H35 (FIG. 4) through which the second external gear 13b passes. Thereby, the second external gear 13b can be easily incorporated inside the second internal gear 30 while suppressing an increase in the radial dimension of the device.

Further, according to the planetary gear device 1 of the first embodiment, between the rotating body 22 of the first internal gear 20 and the first supporting portion 51a, and between the rotating body 22 and the second supporting portion 51b, Sliding members 24 and 25 are provided. Thereby, it is possible to suppress the occurrence of wear of the member between them. Similarly, according to the planetary gear device 1 of the first embodiment, between the rotating body 32 of the second internal gear 30 and the first support member 34 and between the rotating body 32 and the second support member 35 , Sliding members 36 and 37 are provided. Thereby, it is possible to suppress the occurrence of wear of the member between them.

Further, according to the planetary gear device 1 of the first embodiment, the planetary gear device 1 includes a retaining mechanism (a flange portion 21a and a retaining ring 21b) for preventing the support pin 21 from coming off the first support portion 51a and the second support portion 51b. Thereby, even if a small axial displacement occurs in the support pin 21 by repeatedly receiving a load in the radial direction from the first external gear 13a, it is possible to suppress the support pin 21 from falling out therefrom. Similarly, according to the planetary gear device 1 of the first embodiment, the planetary gear device 1 includes a retaining mechanism (a flange portion 31b and a retaining ring 31a) for preventing the support pin 31 from coming off the first support member 34 and the second support member 35. . Thereby, even if a small axial displacement is generated in the support pin 31 by repeatedly receiving the load in the radial direction from the second external gear 13b, it is possible to suppress the support pin 31 from falling out therefrom.

In the planetary gear device 1 according to the first embodiment, the second support portion 51b and the second support member 35 are arranged on the side opposite to the support pins 21 and 31, so that they are radially inward of these portions, and A space is provided between the first external gear 13a and the second external gear 13b. According to the planetary gear device 1 of the first embodiment, the counter weight 18 is provided by effectively utilizing this space. According to this structure, the counterweight 18 can be disposed without increasing the volume of the planetary gear device 1, and further, the counterweight 18 causes the planetary gear associated with the orbital movement (eccentric oscillation) of the external gear member 13. Generation of vibration of the device 1 can be suppressed.

(Embodiment 2)
FIG. 7 is a sectional view showing a planetary gear device 1A according to Embodiment 2 of the present invention. FIG. 7 shows a cross section taken along line AA of FIG.

The planetary gear device 1A according to the second embodiment is mainly different from the planetary gear device 1 according to the first embodiment in that the second support portion 51b, the second support member 35, and the auxiliary pin 39 are omitted. Elements are the same as in the first embodiment. The same components as those in the first embodiment are denoted by the same reference numerals, and detailed description is omitted.

In the second embodiment, the support pins 21A are cantilevered by the first support portions 51a, and the support pins 31A are cantilevered by the first support members 34. Since the support pins 21A and 31A are cantilevered, the axial dimension is shorter than the support pins 21 and 31 of the first embodiment. A mechanism for preventing the output of the support pin 21A from coming off (a flange 21c, which may be changed to a retaining ring) is locked to the sliding member 25. The mechanism for preventing the support pin 31 </ b> A from coming off on the side opposite to the output side (the flange 31 b) is locked by the sliding member 37.

In the planetary gear device 1A according to the second embodiment, similarly to the first embodiment, the rotational motion input to the input shaft 10 causes the first external gear 13a, the first internal gear 20, the second external gear 13b, and The second internal gear 30 can reduce the speed with high efficiency. Then, the reduced rotational motion is output from the output member 52.

<Effects of Embodiment>
According to the planetary gear device 1 </ b> A of the second embodiment, the first eccentric bearing 43 and the second eccentric bearing 44 are configured in the same manner as in the first embodiment. Is played. Further, the first input bearing 41 and the second input bearing 42 are configured in the same manner as in the first embodiment, and the same effects as those of the first embodiment can be obtained with respect to these components.

(Embodiment 3)
FIG. 8 is a sectional view showing a planetary gear device 1B according to Embodiment 3 of the present invention. FIG. 8 shows a cross section taken along line AA of FIG.

The planetary gear device 1 </ b> B of the third embodiment is different from the first embodiment mainly in the structure for supporting the support pin 31 </ b> B and the configuration of the main bearing 46 </ b> B. About the same component, the same code | symbol as Embodiment 1 is attached | subjected and detailed description is abbreviate | omitted.

The second internal gear 30B of the third embodiment includes a plurality of support pins 31B, a plurality of rotating bodies 32, a first support member 34B that supports one axial end of the plurality of support pins 31B, and a plurality of support pins. A second support member that supports the other end of the pin in the axial direction.

The plurality of support pins 31B are integrally formed with the first support member 34B by a single member. The first support member 34B having such a structure can be manufactured by, for example, forging, casting, or shaving.

The main bearing 46B is, for example, a cross roller bearing, does not have a separate inner ring, and the inner ring is integrated with the first support member 34B. That is, the rolling surface (also referred to as a raceway surface) of the inner ring of the main bearing 46B is provided on the first support member 34B. Similarly, the main bearing 46B does not have an individual outer ring, and the outer ring is integrated with the casing 53B. That is, the rolling surface on the outer peripheral side is provided on the casing 53B. The output member 52 and the second internal gear 30B connected to each other are rotatably supported by the fixed member 51 and the casing 53B via the main bearing 46B.

The main bearing 46B is provided so as to be within the range L1 when viewed from the radial direction. The range L1 is a range occupying the length of the amount of protrusion of the support pin 31B from the root position of the portion of the support pin 31B protruding from the first support member 34B in the direction opposite to the direction in which the support pin 31B protrudes.

The main bearing 46B is further provided in a range overlapping the second input bearing 42 when viewed from the radial direction. Further, the center of the main bearing 46B in the axial direction is located on the side opposite to the output side of the center of the second input bearing 42 in the axial direction.

ボ ル ト In the first support member 34B, a bolt hole 34h1 is provided between the second input bearing 42 and the main bearing 46B. The output member 52 is connected to the first support member 34B by a bolt B1 screwed into the bolt hole 34h1. The first support member 34B and the output member 52 may be integrally formed by a single member. In this case, the driven member may be connected to the first support member 34B and the output member 52 via the bolt B1 screwed into the bolt hole 34h1.

<Effects of Embodiment>
Also in the planetary gear device 1B of the third embodiment, by having the same components as the planetary gear device 1 of the first embodiment, the same effects as those of the first embodiment can be obtained with respect to these components.

According to the planetary gear device 1B of the third embodiment, the support pin 31B is integrated with the first support member 34B. Thereby, the strength of the support pin 31B can be improved without increasing the diameter of the support pin 31B, and the manufacturing cost can be reduced by reducing the number of parts.

According to the planetary gear device 1B of the third embodiment, the inner ring of the main bearing 46B is provided integrally with the first support member 34B of the second internal gear 30B. Thus, the large main bearing 46B can be employed while suppressing an increase in the volume of the planetary gear device 1B. Therefore, both downsizing of the planetary gear device 1B and increase of the allowable moment load can be achieved.

Furthermore, according to the planetary gear device 1B of the third embodiment, the main bearing 46B is provided so as to be within the range L1 (FIG. 8). This structure can be easily realized because the support pin 31B is integrally formed with the first support member 34B, and a hole or the like for tightly fitting the support pin 31B into the first support member 34B is not required. With this structure, it is possible to reduce the axial direction of the planetary gear device 1B while increasing the allowable moment load by employing the large main bearing 46B.

<Effects of Embodiment>
Further, according to the planetary gear device 1B of the third embodiment, the structure in which the support pin 31B and the first support member 34B are integrated also functions as a mechanism for preventing the support pin 31B from falling off. For this reason, even if a load in the radial direction is repeatedly applied to the support pin 31B, the support pin 31B does not fall out of the predetermined arrangement.

(Embodiment 4)
FIG. 9 is a sectional view of a planetary gear device according to Embodiment 4 of the present invention. FIG. 9 shows a cross section taken along line AA of FIG. FIG. 10 is a plan view of the configuration of the planetary gear device of FIG. 9 on the output side from the second support member as viewed from the non-output side.

The planetary gear device 1C of the fourth embodiment is different from the first embodiment mainly in the support structure of the support pins 21C and 31C and the bearing structure of the first support member 34C integrated with the output member. The same components as those in the first embodiment are denoted by the same reference numerals, and detailed description is omitted.

The first internal gear 20C of the fourth embodiment includes a plurality of support pins 21C, a plurality of rotating bodies 22 rotatably supported by the plurality of support pins 21C, and a first support that supports the plurality of support pins 21C. And a second support portion 51b.

The fixing member 51 has a groove 51u that is recessed in the radial direction on the inner peripheral portion, and the rotating body 22 is disposed in the groove 51u. One of the two walls partitioning the axial direction of the groove 51u is a first support portion 51a, and the other is a second support portion 51b. The support pin 21C is tightly fitted into a connection hole provided in the first support portion 51a and the second support portion 51b, and is connected thereto. An output-side end of the support pin 21C is provided with a flange 21c that protrudes in the radial direction of the support pin 21C. The support pin 21C is fixed by being passed through the connection hole of the first support portion 51a and the connection hole of the second support portion 51b until the flange portion 21c comes into contact with the second support portion 51b.

The second internal gear 30C of the fourth embodiment includes a plurality of support pins 31C, a plurality of rotating bodies 32 rotatably supported by the plurality of support pins 31C, and a plurality of auxiliary pins 39C. Further, the second internal gear 30C has a first support member 34C and a second support member 35C that support one end and the other end in the axial direction of the plurality of support pins 31C, respectively.

The first support member 34C is integrated with the output member, and is connected to the driven member in a system in which the planetary gear device 1C is incorporated, for example. The first support member 34C has an annular shape having a through hole in the center through which the input shaft 10 passes. The first support member 34C rotatably supports the input shaft 10 via the second input bearing 42.

複数 A plurality of connection holes extending in the axial direction are provided in the first support member 34C in a line in the circumferential direction. The output-side ends of the plurality of support pins 31C and the output-side ends of the plurality of auxiliary pins 39C are connected to these connection holes by interference fitting or the like. It should be noted that the auxiliary pin 39C is disposed between the support pin 31C and the support pin 31C, does not constitute an internal tooth, and the auxiliary pin is not provided on the first internal gear 20C side. Same as 1.

The second support member 35C has an annular shape having a through hole at the center through which the input shaft 10 passes. A plurality of connection holes extending in the axial direction are provided in the second support member 35C in a line in the circumferential direction. The ends of the plurality of support pins 31C on the non-output side and the ends of the plurality of auxiliary pins 39C on the non-output side are connected to these connection holes by interference fitting or the like.

鍔 A flange 31b is provided at an end of the support pin 31C on the opposite side to the output side so as to protrude in the radial direction of the support pin 31C. The support pin 31C is passed through the connection hole and fixed until the flange 31b comes into contact with the bottom of a groove 35u (described later) of the second support member 35C.

The second support member 35C has a width that overlaps with the ends (flanges 21c) of the plurality of opposing support pins 21C when viewed from the radial direction. On the other hand, as shown in FIG. 10, the second support member 35C is provided with a groove 35u that is continuous in the circumferential direction on the non-output side. The groove 35u is provided at a position overlapping the connection hole of the support pin 31C and the auxiliary pin 39C when viewed from the axial direction. The ends of the plurality of support pins 21C facing the second support member 35C are accommodated in the grooves 35u. By moving the end of the support pin 21C relative to the second support member 35C along the groove 35u, the first internal gear 20C and the second internal gear 30C are relatively rotatable.

The first support member 34C also serving as an output member and the second support member 35C are rotatably supported by the casing 53 via the first main bearing 46C and the second main bearing 47C, respectively.

The first main bearing 46C and the second main bearing 47C are angular ball bearings, and are arranged back to back. The back-to-back arrangement can withstand a larger moment load, and a high preload can provide high rigidity of the bearing. The first main bearing 46C and the second main bearing 47C are not limited to angular ball bearings, and various types of bearings can be used. For example, normal ball bearings other than angular bearings may be used.

The first main bearing 46C is disposed at a position overlapping one end face of the support pin 31C in the axial direction when viewed from the radial direction. The second main bearing 47C is disposed at a position overlapping the other end face in the axial direction of the support pin 31C when viewed from the radial direction.

<Effects of Embodiment>
Also in the planetary gear device 1C of the fourth embodiment, by having the same components as the planetary gear device 1 of the first embodiment, the same effects as those of the first embodiment can be obtained with respect to these components.

By the way, when one cross roller bearing is used as the main bearing rotatably supporting the output member (the first support member 34C in the fourth embodiment), it is difficult to obtain high moment rigidity at the location of the main bearing. In particular, when a small cross roller bearing is employed due to a demand for downsizing of the planetary gear device, it is more difficult to obtain high moment rigidity at the location of the main bearing. In such a configuration, when a moment load is applied to the output member, the moment load is transmitted to the point of action using the output member as a power point, the main bearing as a fulcrum, the support pin 31C, and the rotating body 32 as points of action. Fatigue is applied to the support pin 31C and the rotating body 32.

Therefore, according to the planetary gear device 1C of the fourth embodiment, the first support member 34C also serving as the output member and the second support member 35C are provided via the first main bearing 46C and the second main bearing 47C, respectively. It is supported by a casing 53. That is, the second internal gear 30C is supported from two places using the first main bearing 46C and the second main bearing 47C arranged on both sides of the support pin 31C with the rotating body 32 interposed therebetween. Thereby, the rigidity of the configuration supporting the support pin 31C is improved, and even when a moment load is applied to the output member (the first support member 34C), the moment load is prevented from being transmitted to the support pin 31C and the rotating body 32. it can. Therefore, the life of the support pin 31C and the rotating body 32 can be extended.

Further, according to the planetary gear device 1C of the fourth embodiment, since the plurality of auxiliary pins 39C connect the first support member 34C and the second support member 35C, the rigidity of the configuration supporting the support pin 31C can be further improved. . If a minute deformation occurs in the configuration supporting the support pin 31C and the rotating body 32, an extra load is transmitted to the support pin 31C and the rotating body 32. However, such small deformation is unlikely to occur due to the auxiliary pin 39C, and it is possible to suppress transmission of an unnecessary load to the support pin 31C and the rotating body 32.

The first main bearing 46C and the second main bearing 47C are provided at positions overlapping the one end face and the other end face of the support pin 31C, respectively, when viewed from the radial direction. Thereby, transmission of a moment load to the support pin 31C can be further suppressed, and the axial length of the planetary gear device 1C can be reduced.

Further, according to the planetary gear device 1C of the fourth embodiment, the groove 35u extending in the circumferential direction is provided in the second support member 35C of the second internal gear 30C, and the tip of the support pin 21C of the first internal gear 20C. Is accommodated in the groove 35u. Thereby, the first internal gear 20C is brought closer to the second internal gear 30C while the axial length of the second support member 35C is increased, and the contact area with the second main bearing 47C is secured. The overall axial length of the gear device 1C can be reduced.

(Embodiment 5)
FIG. 11 is a sectional view of a planetary gear device according to Embodiment 5 of the present invention. FIG. 11 shows a cross section taken along line AA of FIG.

The planetary gear device 1D of the fifth embodiment is different from the fourth embodiment in that a tapered roller bearing (or an angular roller bearing) is used as the first main bearing 46D and the second main bearing 47D, and the other components are the same as those of the fourth embodiment. . With such a configuration, the same operation and effect as those of the fourth embodiment can be obtained.

(Embodiment 6)
FIG. 12 is a sectional view showing a planetary gear device according to Embodiment 6 of the present invention. FIG. 12 shows a cross section taken along line A1-A1 of FIG.

The planetary gear device 1E according to the sixth embodiment is substantially the same as the first embodiment except that the relationship between the plurality of rotating bodies 32E of the second internal gear 30 and the casing 53E is different. About the same component, the same code | symbol as Embodiment 1 is attached | subjected and detailed description is abbreviate | omitted.

遊 The planetary gear device 1E of the sixth embodiment is configured such that the inner peripheral surface of the casing 53E and the outer peripheral surfaces of the plurality of rotating bodies 32E of the second internal gear 30 are in contact with each other. In the present embodiment, all the rotating bodies 32E are in contact with the inner peripheral surface of the casing 53E. However, the present invention is not limited to this, and only a part of the rotating bodies 32E may be configured to be in contact. That is, the plurality of rotating bodies 32E are used both as the rotating body for bearings and the rotating body for internal teeth. According to this configuration, the plurality of rotators 32E arranged on the same pitch radius centered on the rotation axis O1 also function as rolling elements that roll using the inner peripheral surface of the casing 53E as a rolling surface. Thereby, the second internal gear 30 functions as a large-diameter bearing, and the allowable moment load of the output member 52 connected to the second internal gear 30 can be increased.

Furthermore, in the planetary gear device 1E of the sixth embodiment, the hardness of the material of the rotating body 32E is higher than the hardness of the material of the casing 53E. According to this configuration, it is possible to suppress wear of the rotating body 32E that also functions as a rolling element of the bearing.

The rotating body 32E is not limited to a cylindrical shape whose central axis is parallel to the axial direction, but may be a ball shape, or may be a conical shape or a cylindrical shape whose central axis is inclined with respect to the axial direction. In the case of an inclined cone or cylindrical shape, the outer peripheral surface of the second external gear 13b and the inner peripheral surface of the casing 53E may be provided with an inclination in accordance with the inclination. With such a configuration, when the second internal gear 30 functions as a large-diameter bearing, characteristics of a ball bearing or a conical roller bearing can be added to this bearing.

(Embodiment 7)
FIG. 13 is a sectional view showing a planetary gear device according to Embodiment 7 of the present invention. FIG. 13 is a sectional view taken along line A1-A1 of FIG.

遊 A planetary gear device 1F according to the seventh embodiment is substantially the same as the first embodiment except that the configuration of the second internal gear 30F is different. About the same component, the same code | symbol as Embodiment 1 is attached | subjected and detailed description is abbreviate | omitted.

The second internal gear 30F according to the seventh embodiment includes a plurality of support pins 31F, a plurality of rotators 32 in a first row rotatably supported by the plurality of support pins 31F, and a plurality of support pins 31F. A plurality of rotators 32F in a second row freely supported. That is, the plurality of rotating bodies 32 function as rotating bodies for internal teeth, and the plurality of rotating bodies 32F function as rotating bodies for bearings. The rotating body 32 and the rotating body 32F are arranged side by side in the axial direction.

The support pin 31F is longer in the axial direction than the support pin 31 of the first embodiment by the amount of supporting the two rotating bodies 32 and 32F in the axial direction.

The rotator 32 contacts (engages) with the second external gear 13 b and does not contact the inner peripheral surface of the casing 53.

The rotating body 32F has a larger outer diameter than the rotating body 32, and is supported by the support pin 31F so as to be rotatable independently of the rotating body 32 adjacent in the axial direction (for example, via a needle bearing). The rotating body 32F is supported at a position overlapping with the intermediate portion 13c of the external gear member 13 when viewed from the radial direction, does not contact the second external gear 13b and the external gear member 13, and has an inner peripheral surface of the casing 53. Contact The hardness of the material of the rotating body 32F is higher than the hardness of the material of the casing 53. The rotator 32F may be provided on all the support pins 31F, or may be provided only on some support pins 31F.

滑 り A sliding member 37F is provided between the rotating body 32 and the rotating body 32F. The sliding member 37F has a washer shape, and its position is regulated by passing the support pin 31F. The sliding member 37F has a smaller coefficient of friction on the surface than the rotating bodies 32 and 32F, prevents the rotating bodies 32 and 32F from directly rubbing each other, and suppresses wear of these members. Similarly, a sliding member may be provided between the rotating body 32F and the second support member 35.

<Effects of Embodiment>
Also in the planetary gear device 1F of the seventh embodiment, by having the same components as the planetary gear device 1 of the first embodiment, the same effects as those of the first embodiment can be obtained with respect to these components.

Further, according to the planetary gear device 1F of the seventh embodiment, the plurality of internal teeth (the support pin 31F and the rotating bodies 32 and 32F) arranged on the same pitch radius centered on the rotation axis O1 are positioned on the inscribed circle side. From the second external gear 13b and the casing 53 from the circumscribed circle side. Thereby, the plurality of internal teeth function as rolling elements that roll using the outer peripheral surface of the second external gear 13b and the inner peripheral surface of the casing 53 as rolling surfaces, and the second internal gear 30F has a large diameter. Also functions as a bearing. The rigidity of the planetary gear device 1 </ b> F with respect to the moment applied to the output member 52 is improved by the function of the bearing, and the allowable moment load of the output member 52 can be increased.

Further, according to the planetary gear device 1F of the seventh embodiment, the rotating body 32 that contacts the second external gear 13b and the rotating body 32F that contacts the casing 53 are separately provided on one support pin 31F, Each can rotate independently. Therefore, when the output member 52 rotates, the rotating bodies 32 and 32F smoothly roll while contacting the second external gear 13b and the casing 53, respectively, and a rotational movement with little friction is realized.

According to the planetary gear device 1F of the seventh embodiment, since the hardness of the material of the rotating body 32F is higher than the hardness of the material of the casing 53, the wear of the rotating body 32F functioning as a rolling element of the bearing can be suppressed.

In addition, the rotating body 32, the rotating body 32F, or both of them are not limited to a cylindrical shape whose central axis is parallel to the axial direction, and may be a ball shape, or a conical shape or inclined shape whose central axis is inclined with respect to the axial direction. It may have a cylindrical shape. When the shape of the cone or cylinder is inclined, the outer peripheral surface of the second external gear 13b and the inner peripheral surface of the casing 53 may be inclined in accordance with the inclination. With such a configuration, when the second internal gear 30F functions as a large-diameter bearing, the characteristics of a ball bearing or a conical roller bearing can be added to this bearing.

(Embodiment 8)
FIG. 14 is a sectional view of a planetary gear device according to Embodiment 8 of the present invention. FIG. 14 shows a cross section taken along line AA of FIG. FIG. 15 is a cross-sectional view taken along line EE of the planetary gear device of FIG.

遊 A planetary gear device 1G according to the eighth embodiment is substantially the same as the first embodiment except that the configuration of the second internal gear 30G is different. About the same component, the same code | symbol as Embodiment 1 is attached | subjected and detailed description is abbreviate | omitted.

The second internal gear 30 </ b> G of the eighth embodiment includes a plurality of rotating bodies 33 </ b> G in addition to the components of the second internal gear 30 of the first embodiment.

The plurality of rotating bodies 33G are rotatably supported by a plurality of auxiliary pins 39G via bearings (for example, needle bearings). The rotator 33G has a cylindrical shape. As shown in FIGS. 14 and 15, the plurality of rotating bodies 33 </ b> G do not contact the external gear member 13 and the second external gear 13 b but contact the inner peripheral surface of the casing 53. In addition, the rotating body 32 contacts (engages) with the second external gear 13 b and does not contact the inner peripheral surface of the casing 53. The hardness of the material of the rotating body 33G is higher than the hardness of the material of the casing 53. That is, in the second internal gear 30G, the plurality of rotating bodies 32 function as internal rotating bodies, and the plurality of rotating bodies 33G function as bearing rotating bodies. The rotating body 32 and the rotating body 33G are arranged side by side in the circumferential direction. In the present embodiment, the rotator 33G is disposed between all the rotators 32. However, the present invention is not limited to this, and only the rotator 32 is provided between some of the rotators 32. 33G may be arranged.

A flange 39b that protrudes in the radial direction of the auxiliary pin 39G is provided at one end of the auxiliary pin 39G in the axial direction (opposite output side), and the other end (output side) of the auxiliary pin 39G in the axial direction is provided. A retaining ring (E ring, C ring, etc.) 39a is attached. The flange 39b and the retaining ring 39a prevent the auxiliary pin 39G from coming out of the pin holes of the first support member 34 and the second support member 35.

Further, between the first support member 34 and the rotating body 33G, there is provided a washer-shaped sliding member 36G through which an auxiliary pin 39G is passed. A washer-shaped slide member 37G through which an auxiliary pin 39G is passed is provided between the second support member 35 and the rotating body 33G. By these sliding members 36G and 37G, it is possible to prevent the rotating body 33G from sliding against the first support member 34 and the second support member 35, and to prevent them from being worn.

<Effects of Embodiment>
The planetary gear device 1G of the eighth embodiment also has the same components as those of the planetary gear device 1 of the first embodiment, so that the same effects as those of the first embodiment can be obtained with respect to these components.

Furthermore, according to the planetary gear device 1G of the eighth embodiment, the second external gear 13b contacts the rotating body 32 of the support pin 31 from the inscribed circle side, while the rotating body 33G of the auxiliary pin 39G contacts the rotating body 32G of the auxiliary pin 39G. On the other hand, the casing 53 comes into contact from the circumscribed circle side. As a result, the rotating bodies 32 and 33G function as rolling elements that use the outer peripheral surface of the second external gear 13b and the inner peripheral surface of the casing 53 as rolling surfaces, and the second internal gear 30G has a large diameter. Also functions as a bearing. The rigidity of the planetary gear device 1G with respect to the moment applied to the output member 52 is improved by the function of the bearing, and the allowable moment load of the output member 52 can be increased.

Furthermore, according to the planetary gear device 1G of the eighth embodiment, the rotating body 32 that contacts the second external gear 13b and the rotating body 33G that contacts the casing 53 are separately provided, and each can rotate independently. It is. Therefore, when the output member 52 rotates, the rotating bodies 32 and 33G roll smoothly while contacting the second external gear 13b and the casing 53, respectively, and a rotational movement with less slippage is realized.

According to the planetary gear device 1G of the eighth embodiment, since the hardness of the material of the rotating body 33G is higher than the hardness of the material of the casing 53, the wear of the rotating body 33G functioning as a rolling element of the bearing can be suppressed.

In addition, the rotating body 32, the rotating body 33G, or both of them are not limited to a cylindrical shape whose central axis is parallel to the axial direction, and may have a ball shape, a conical shape in which the central axis is inclined with respect to the axial direction, or an inclined shape. It may have a cylindrical shape. When the shape of the cone or cylinder is inclined, the outer peripheral surface of the second external gear 13b and the inner peripheral surface of the casing 53 may be inclined in accordance with the inclination. With such a configuration, when the second internal gear 30G functions as a large-diameter bearing, characteristics of a ball bearing or a conical roller bearing can be added to this bearing.

(Embodiment 9)
FIG. 16 is a cross-sectional view showing the location of the rotating body of the second internal gear in the planetary gear device according to Embodiment 9 of the present invention. The planetary gear device 1H of the ninth embodiment has substantially the same configuration as the planetary gear device 1 of FIG. 1, and FIG. 16 shows a cross section taken along line BB of FIG. FIG. 17 is a diagram illustrating an example of an industrial robot to which the planetary gear device according to Embodiment 9 is applied.

The planetary gear device 1H of the ninth embodiment differs from the first embodiment in the relationship between some of the rotating bodies 32H and the casing 53 among the plurality of rotating bodies 32, 32H of the second internal gear 30H, and other constituent elements. Is the same as in the first embodiment. The same components are denoted by the same reference numerals as in the first embodiment, and detailed description is omitted.

As shown in FIG. 17, when the planetary gear device 1H is incorporated in a driven device 100 (for example, an industrial robot), the driven member 101 connected to the output member 52 has only a 90-degree range W101. It is regulated to rotate. In this case, the second internal gear 30H connected to the output member 52 rotates only in the range of 90 °, and does not rotate any more.

On the other hand, among the plurality of internal teeth (rotating bodies 32 and 32H) of the second internal gear 30H, the one receiving the load from the second external gear 13b is located in the eccentric range W1 of the second external gear 13b. Only divisions, not all. For example, if the total number of the internal teeth (rotating bodies 32 and 32H) is 13, five of these mesh with the external teeth in the eccentric range of the second external gear 13b, and load is applied from the external teeth. receive.

When the rotation range W101 of the second internal gear 30H is determined to be 90 degrees, the five internal teeth (rotating bodies 32 and 32H) that receive a load from the external teeth rotate the second internal gear 30H. Depending on the position, any five internal teeth in the range W2 in FIG. The angle of the range W2 is the angle of the range W1 of the internal teeth receiving the load plus the angle (90 °) of the rotation range W101 of the second internal gear 30H. That is, among the plurality of internal teeth (rotating bodies 32 and 32H) of the second internal gear 30H, the internal teeth in the range W3 excluding the range W2 rotate in the range where the driven member 101 is determined. As long as there is no load from the second external gear 13b.

In the ninth embodiment, of the plurality of rotating bodies 32, 32H of the second internal gear 30, one or more rotating bodies 32H in the range W3 are in contact with the inner peripheral surface of the casing 53, and the other plurality of rotating bodies 32H are located in the range W3. The rotating body 32 is arranged so as to be separated from the inner peripheral surface of the casing 53. Such a configuration can be dealt with, for example, by providing the support pin 31 that supports the rotating body 32H at a position radially outward from the support pin 31 that supports the rotating body 32. The plurality of rotating bodies 32 function as rotating bodies for internal teeth, and one or a plurality of rotating bodies 32H function as rotating bodies for bearings.

The material of the rotating body 32H may be higher than the hardness of the material of the casing 53.

The range W3 in which no load is received from the second external gear 13b varies depending on the rotation range and the reduction ratio of the driven member 101. Usually, if the rotation range is regulated within 270 °, one range W3 is required. The size includes the internal teeth described above. Therefore, when the planetary gear device 1H is incorporated into such a regulated device, the internal teeth located in the range W3 are the rotating body 32H that contacts the inner peripheral surface of the casing 53, and the other internal teeth are What is necessary is just to make it the several rotating body 32 which does not contact the inner peripheral surface of the casing 53.

<Effects of Embodiment>
Also in the planetary gear device 1H of the ninth embodiment, by having the same components as the planetary gear device 1 of the first embodiment, the same effects as those of the first embodiment can be obtained with respect to these components.

Furthermore, according to the planetary gear device 1H of the ninth embodiment, the second external gear 13b comes in contact with the plurality of rotating bodies 32 in the range W2 from the inscribed circle side, while one or the other in the range W3. The casing 53 contacts the plurality of rotating bodies 32H from the circumscribed circle side. Therefore, the second internal gear 30H including the rotating bodies 32 and 32H comes into contact with the second external gear 13b and the casing 53, and the arrangement thereof is maintained. Thereby, the displacement of the second internal gear 30H with respect to the moment applied to the output member 52 is suppressed, and the rigidity of the planetary gear device 1H with respect to this moment is improved. Therefore, the allowable moment load of the output member 52 can be increased.

According to the planetary gear device 1 </ b> H of the ninth embodiment, only the rotating body 32 </ b> H in the range W <b> 3 that does not receive a load from the second external gear 13 b contacts the casing 53. Therefore, when the second internal gear 30H and the output member 52 rotate, the rotating bodies 32 and 32H roll smoothly, and a rotational movement with less slippage is realized.

Further, by making the hardness of the material of the rotating body 32H higher than the hardness of the material of the casing 53, when the rotating body 32H rolls on the casing 53 by contacting the inner peripheral surface, wear of the rotating body 32H is reduced. Can be suppressed.

The embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiment. For example, in the embodiment, a component integrally formed by a single member may be replaced with a component that is divided into a plurality of members and connected or fixed to each other. Further, a component configured by connecting a plurality of members may be replaced with a component integrally formed by a single member. Other details described in the embodiments can be appropriately changed without departing from the spirit of the invention. For example, in the above-described embodiment, the support pins and the auxiliary pins are connected to the first support portion and the second support portion, and the first support member and the second support member by interference fit, but are not limited thereto. Instead, they may be connected so as to be relatively rotatable by, for example, a clearance fit, or may be connected by bolts or the like.

Further, in the above embodiment, the first eccentric body bearing and the second eccentric body bearing are configured such that the angular bearings are arranged back to back. However, the present invention is not limited to this. A configuration in which they are arranged together may be used. Further, the present invention is not limited to the angular bearing, and may be, for example, a normal ball bearing or a cylindrical roller bearing.

The present invention can be used for a planetary gear device.

1, 1A to 1H Planetary gear device 10 Input shaft 10A Eccentric body 13 External gear member 13a First external gear 13b Second external gear 13c Intermediate portion 18 Counterweight 20, 20C First internal gear 21, 21A, 21C Support pins 21a, 21c Flange portion 21b Retaining ring 22 Rotating body 24, 25 Sliding member 30, 30B, 30F to 30H Second internal gear 31, 31, A, 31B, 31C, 31F Support pin 31a Retaining ring 31b Flange portion 32, 32E , 32F, 32H, 33G Rotating body 34, 34B, 34C First support member 35, 35C Second support member 35u Groove (groove for accommodating the end of support pin 21C)
36, 37, 37F, 36G, 37G Sliding member 39, 39C, 39G Auxiliary pin 41 First input bearing 42 Second input bearing 43 First eccentric bearing 44 Second eccentric bearing 46, 46B Main bearing 46C, 46D First Main bearings 47C, 47D Second main bearing 51 Fixing member 51a First support portion 51b Second support portion 52 Output member 53, 53B, 53E Casing H35, H51 Through hole L1 Range in which main bearing can be accommodated in radial direction O1 Rotating shaft O2 Eccentric shaft 100 Driven device 101 Driven member W101 Rotation range of driven member

Claims (24)

1. A first internal gear and a second internal gear,
   A first external gear that meshes with the first internal gear;
   A second external gear that meshes with the second internal gear;
   An eccentric body for orbiting the first external gear and the second external gear;
   With
   The first external gear and the second external gear rotate integrally,
   Each of the first internal gear and the second internal gear has a support and a plurality of internal teeth, and each of the plurality of internal teeth includes a rotating body rotatably supported by the support. ,
   Planetary gear set.
2. A first eccentric body bearing disposed between the eccentric body and the first external gear;
   A second eccentric body bearing disposed between the eccentric body and the second external gear;
   Further comprising
   The first internal gear is connected to a fixed side, the second internal gear is connected to an output side,
   The first eccentric bearing and the second eccentric bearing are angular bearings and are arranged back to back.
   The planetary gear device according to claim 1.
3. An input shaft having the eccentric body;
   A first input bearing and a second input bearing that support the input shaft;
   Further comprising
   The first eccentric bearing and the second eccentric bearing are disposed between the first input bearing and the second input bearing,
   The first input bearing and the second input bearing are angular bearings, and are arranged face to face.
   The planetary gear device according to claim 2.
4. At least one of the support of the first internal gear and the support of the second internal gear has a plurality of support pins on which the plurality of rotating bodies are respectively fitted, and a single support pin. And a supporting member integrally formed by the members of
   The planetary gear device according to claim 2 or 3.
5. Further comprising a main bearing rotatably supporting the support member,
   The inner ring rolling surface of the main bearing is provided integrally with the support member,
   The planetary gear device according to claim 4.
6. The main bearing, when viewed from the radial direction, is located on a side opposite to a direction in which the support pin protrudes from a base position of the support pin of the support member and within a range corresponding to the length of the support pin.
   The planetary gear device according to claim 5.
7. The first internal gear is connected to a fixed side, the second internal gear is connected to an output side,
   The support of the second internal gear is:
   A plurality of support pins to which the plurality of rotating bodies are respectively fitted;
   A first support member arranged on one of the plurality of support pins in the axial direction and connected to one end of the plurality of support pins;
   A second support member disposed on the other side in the axial direction of the plurality of support pins and connected to the other end of the plurality of support pins;
   Has,
   Furthermore,
   A first main bearing rotatably supporting the first support member;
   A second main bearing rotatably supporting the second support member;
   The planetary gear device according to claim 1, further comprising:
8. The support of the second internal gear has an auxiliary pin that does not constitute an internal tooth, is disposed between a pair of support pins that are circumferentially adjacent to each other among the plurality of support pins,
   The auxiliary pin is connected to the first support member and the second support member,
   The planetary gear device according to claim 7.
9. One end face of the plurality of support pins in the axial direction and the first main bearing overlap when viewed from the radial direction,
   The planetary gear device according to claim 7.
10. The support body of the first internal gear has a plurality of support pins to which the plurality of rotating bodies are respectively fitted,
    The second support member has an annular groove continuous in the circumferential direction,
    Ends of the plurality of support pins of the first internal gear are arranged in the groove.
    The planetary gear device according to any one of claims 7 to 9.
11. Further comprising a casing,
    The first internal gear is connected to a fixed side, the second internal gear is connected to an output side,
    The casing rotatably supports the support of the second internal gear,
    The second internal gear includes a bearing rotating body rotatably supported by the support and in contact with the casing.
    The planetary gear device according to claim 1.
12. At least a part of the plurality of rotating bodies of the second internal gear is also used as the bearing rotating body,
    The planetary gear device according to claim 11.
13. The bearing rotating body is provided side by side in the axial direction or circumferential direction with the rotating body,
    The planetary gear device according to claim 11.
14. The hardness of the material of the bearing rotating body is higher than the hardness of the material of the casing,
    The planetary gear device according to any one of claims 11 to 13.
15. The rotating body contacts the second external gear without contacting the casing,
    The bearing rotating body contacts the casing without contacting the second external gear,
    The planetary gear device according to any one of claims 11 to 14.
16. The planetary gear device according to claim 15, wherein the bearing rotating body is provided in a range that does not receive a load from the second external gear when the planetary gear device is incorporated in a driven device.
17. The first internal gear is connected to a fixed side, the second internal gear is connected to an output side,
    When at least one of the support of the first internal gear and the support of the second internal gear is referred to as a first support, the first support is:
    A plurality of support pins to which the plurality of rotating bodies are respectively fitted;
    A first support member arranged on one of the plurality of support pins in the axial direction and connected to one end of the plurality of support pins;
    A second support member disposed on the other side in the axial direction of the plurality of support pins and connected to the other end of the plurality of support pins;
    The planetary gear device according to claim 1, comprising:
18. The first support has an auxiliary pin that is arranged between a pair of support pins that are adjacent to each other in the circumferential direction among the plurality of support pins and that does not form an internal tooth.
    The auxiliary pin is connected to the first support member and the second support member,
    The planetary gear device according to claim 17.
19. Both the support of the first internal gear and the support of the second internal gear have a structure as the first support,
    The second internal gear has the auxiliary pin,
    The first internal gear does not include the auxiliary pin;
    The planetary gear device according to claim 18.
20. The second support member has a hole through which the second external gear can pass;
    The planetary gear device according to any one of claims 17 to 19.
21. A sliding member is provided between at least one of the first support member and the second support member and the rotating body,
    The planetary gear device according to any one of claims 17 to 20.
22. Further comprising a retaining mechanism for preventing the support pin from coming off in the axial direction from the first support member and the second support member,
    The planetary gear device according to any one of claims 17 to 21.
23. The support pin is formed integrally with one of the first support member and the second support member by a single member,
    The planetary gear device according to any one of claims 17 to 22.
24. 24. The planetary gear device according to any one of claims 17 to 23, further comprising a counter weight disposed between the first external gear and the second external gear.

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