JP2022097205A - Inscribed gearing type planetary gear device, and its manufacturing method - Google Patents

Abstract

To provide an inscribed gearing type planetary gear device in which a problem caused by defective centering hardly occurs, and its manufacturing method.SOLUTION: A bearing member 6A has an outer ring 62A, an inner ring 61A, and a plurality of rolling elements 63, and the inner ring 61A is supported relatively rotatably on a rotation axis Ax1 with respect to the outer ring 62A. An internal gear 2 has an annular gear body 22, and a plurality of outer pins 23 retained on an inner peripheral surface of the gear body 22 in an auto-rotatable state, and configuring internal teeth 21. The planetary gear 3 has external teeth partially engaged with the internal teeth 21. A plurality of inner pins 4 relatively rotate to the internal gear 2 while revolving in loose holes 32 in a state of being respectively inserted to the plurality of loose holes 32 formed on the planetary gear 3. The outer ring 62A is disposed in a seamless and continuous state in a direction in parallel with the gear body 22 and the rotation axis Ax1.SELECTED DRAWING: Figure 11

Description

The present disclosure relates to an inscribed meshing planetary gear device in general, and a method for manufacturing the same. And its manufacturing method.

As a related technique, a so-called eccentric swing type gear device in which a planetary gear engages inscribed with an internal tooth gear while swinging eccentrically is known (see, for example, Patent Document 1). In the gear device according to the related technique, the eccentric body is formed integrally with the input shaft, and the planetary gear is attached to the eccentric body via the eccentric body bearing. External teeth such as an arc tooth profile are formed on the outer circumference of the planetary gear.

The internal gear is configured by rotatably incorporating a plurality of external pins (roller pins), one of which constitutes an internal tooth, on the inner peripheral surface of a gear body (internal gear body) that also serves as a casing. A plurality of free fitting holes (inner roller holes) are formed in the planetary gear at appropriate intervals in the circumferential direction, and an inner pin and an inner roller are inserted into the free fitting holes. The inner pin is connected to the carrier on one end side in the axial direction thereof, and the carrier is rotatably supported by the casing via a cross roller bearing. This gear device can be used as a gear device that takes out the rotation corresponding to the rotation component of the planetary gear when the internal gear is fixed from the carrier.

Japanese Patent Application Laid-Open No. 2003-74646

In the above-mentioned related technology configuration, the gear body is sandwiched between the outer ring of the cross roller bearing and the casing (third casing) and fixed with bolts, and the internal gear and the cross roller bearing are centered. It is difficult to improve the accuracy. Therefore, poor centering may lead to problems such as vibration and deterioration of transmission efficiency.

An object of the present disclosure is to provide an inscribed meshing planetary gear device in which defects due to poor centering are unlikely to occur, and a method for manufacturing the same.

The inscribed meshing planetary gear device according to one aspect of the present disclosure includes a bearing member, an internal gear, a planetary gear, and a plurality of internal pins. The bearing member has an outer ring, an inner ring arranged inside the outer ring, and a plurality of rolling elements arranged between the outer ring and the inner ring, and the inner ring is centered on a rotation axis with respect to the outer ring. It is relatively rotatably supported. The internal gear has an annular gear body and a plurality of external pins held on the inner peripheral surface of the gear body in a rotatable state to form internal teeth. The planetary gear has external teeth that partially mesh with the internal teeth. The plurality of internal pins rotate relative to the internal gear while revolving in the free fitting holes in a state of being inserted into the plurality of free fitting holes formed in the planetary gear. The outer ring is seamlessly and continuously provided in a direction parallel to the gear body and the rotation axis.

The method for manufacturing an inscribed meshing planetary gear device according to one aspect of the present disclosure is a method for manufacturing an inscribed meshing planetary gear device including a bearing member, an internal gear, a planetary gear, and a plurality of internal pins. The bearing member has an outer ring and an inner ring arranged inside the outer ring, and the inner ring is rotatably supported with respect to the outer ring about a rotation axis. The internal gear has an annular gear body and a plurality of external pins held on the inner peripheral surface of the gear body in a rotatable state to form internal teeth. The planetary gear has external teeth that partially mesh with the internal teeth. The plurality of internal pins rotate relative to the internal gear while revolving in the free fitting holes in a state of being inserted into the plurality of free fitting holes formed in the planetary gear. The manufacturing method includes a step of integrally forming the outer ring and the gear body by processing one base material.

According to the present disclosure, it is possible to provide an inscribed meshing planetary gear device in which defects caused by poor centering are unlikely to occur, and a method for manufacturing the same.

FIG. 1 is a perspective view showing a schematic configuration of an actuator including an inscribed meshing planetary gear device according to a basic configuration. FIG. 2 is a schematic exploded perspective view of the above-mentioned inscribed meshing planetary gear device as viewed from the output side of the rotating shaft. FIG. 3 is a schematic cross-sectional view of the inscribed meshing planetary gear device of the same as above. FIG. 4 is a sectional view taken along line A1-A1 of FIG. 3, showing the inscribed meshing planetary gear device of the same as above. FIG. 5A is a perspective view showing the planetary gear of the inscribed meshing planetary gear device of the same as above as a single unit. FIG. 5B is a front view showing the planetary gear of the inscribed meshing planetary gear device of the same as above as a single unit. FIG. 6A is a perspective view showing the bearing member of the inscribed meshing planetary gear device of the same as above as a single unit. FIG. 6B is a front view showing the bearing member of the inscribed meshing planetary gear device of the same as above as a single unit. FIG. 7A is a perspective view showing the eccentric axis of the inscribed meshing planetary gear device of the same as above as a single unit. FIG. 7B is a front view showing the eccentric axis of the inscribed meshing planetary gear device of the same as above as a single unit. FIG. 8A is a perspective view showing the support of the inscribed meshing planetary gear device of the same as above as a single body. FIG. 8B is a front view showing the support of the inscribed meshing planetary gear device of the same as above as a single body. FIG. 9 is an enlarged view of region Z1 of FIG. 3, showing the inscribed meshing planetary gear device of the same as above. FIG. 10 is a sectional view taken along line B1-B1 of FIG. 3, showing the inscribed meshing planetary gear device of the same as above. FIG. 11 is a schematic cross-sectional view of the inscribed meshing planetary gear device according to the first embodiment. FIG. 12 is a side view of the above-mentioned inscribed meshing planetary gear device as viewed from the output side of the rotating shaft. FIG. 13 is a sectional view taken along line A1-A1 of FIG. 11 showing the inscribed meshing planetary gear device of the same as above. FIG. 14 is a cross-sectional view taken along the line B1-B1 of FIG. 11 showing the inscribed meshing planetary gear device of the same as above, and a partially enlarged view thereof. FIG. 15 is a schematic cross-sectional view of a main part of the inscribed meshing planetary gear device of the same as above. FIG. 16 is a schematic cross-sectional view of a main part of the inscribed meshing planetary gear device of the same as above, and is a diagram schematically showing a path of a lubricant. FIG. 17 is a schematic cross-sectional view of a wheel device using the above-mentioned inscribed meshing planetary gear device. FIG. 18A is a schematic cross-sectional view of a main part of the inscribed meshing planetary gear device according to the modified example of the first embodiment. FIG. 18B is a schematic cross-sectional view of a main part of the inscribed meshing planetary gear device according to the modified example of the first embodiment. FIG. 19A is a schematic cross-sectional view of a main part of the inscribed meshing planetary gear device according to the second embodiment. FIG. 19B is a sectional view taken along line A1-A1 of FIG. 19A showing a main part of the inscribed meshing planetary gear device of the same as above. FIG. 20 is a schematic cross-sectional view of a main part of the inscribed meshing planetary gear device of the same as above, and is a diagram schematically showing a path of a lubricant.

(Basic configuration)
(1) Overview Hereinafter, an outline of the inscribed meshing planetary gear device 1 according to this basic configuration will be described with reference to FIGS. 1 to 3. The drawings referred to in the present disclosure are all schematic views, and the ratio of the size and the thickness of each component in the drawing does not necessarily reflect the actual dimensional ratio. For example, the tooth profile, dimensions, number of teeth, etc. of the internal teeth 21 and the external teeth 31 in FIGS. 1 to 3 are merely schematically represented for the sake of explanation, and are limited to the shapes shown in the drawings. Not the purpose.

The inscribed meshing planetary gear device 1 (hereinafter, also simply referred to as “gear device 1”) according to this basic configuration is a gear device including an internal gear 2, a planetary gear 3, and a plurality of internal pins 4. .. In this gear device 1, the planetary gear 3 is arranged inside the annular internal gear 2, and the eccentric body bearing 5 is arranged inside the planetary gear 3. The eccentric body bearing 5 has an eccentric inner ring 51 and an eccentric outer ring 52, and the eccentric inner ring 51 rotates around a rotation axis Ax1 (see FIG. 3) deviated from the center C1 (see FIG. 3) of the eccentric inner ring 51. The planetary gear 3 is oscillated by (eccentric motion). The eccentric body ring 51 rotates (eccentric movement) around the rotation axis Ax1 by rotating the eccentric shaft 7 inserted into the eccentric body ring 51, for example. Further, the inscribed meshing planetary gear device 1 further includes a bearing member 6 having an outer ring 62 and an inner ring 61. The inner ring 61 is arranged inside the outer ring 62 and is rotatably supported relative to the outer ring 62.

The internal gear 2 has internal teeth 21 and is fixed to the outer ring 62. In particular, in this basic configuration, the internal gear 2 has an annular gear body 22 and a plurality of external pins 23. The plurality of outer pins 23 are held on the inner peripheral surface 221 of the gear body 22 in a state in which they can rotate, and form the inner teeth 21. The planetary gear 3 has external teeth 31 that partially mesh with the internal teeth 21. That is, inside the internal gear 2, the planetary gear 3 is inscribed with respect to the internal gear 2, and a part of the external tooth 31 is in mesh with a part of the internal tooth 21. In this state, when the eccentric shaft 7 rotates, the planetary gear 3 swings, the meshing position between the internal teeth 21 and the external teeth 31 moves in the circumferential direction of the internal gear 2, and the planetary gear 3 and the internal gear 3 Relative rotation according to the difference in the number of teeth from 2 occurs between both gears (internal gear 2 and planetary gear 3). Here, assuming that the internal gear 2 is fixed, the planetary gear 3 rotates (rotates) with the relative rotation of both gears. As a result, the planetary gear 3 can obtain a rotational output decelerated at a relatively high reduction ratio according to the difference in the number of teeth of both gears.

This type of gear device 1 is used to take out the rotation corresponding to the rotation component of the planetary gear 3 as, for example, the rotation of the output shaft integrated with the inner ring 61 of the bearing member 6. As a result, the gear device 1 functions as a gear device having a relatively high reduction ratio with the eccentric shaft 7 as the input side and the output shaft as the output side. Therefore, in the gear device 1 according to this basic configuration, the planetary gear 3 and the inner ring 61 are connected by a plurality of inner pins 4 in order to transmit the rotation corresponding to the rotation component of the planetary gear 3 to the inner ring 61 of the bearing member 6. connect. The plurality of internal pins 4 rotate relative to the internal gear 2 while revolving in the free fitting holes 32 in a state of being inserted into the plurality of free fitting holes 32 formed in the planetary gear 3. .. That is, the free fitting hole 32 has a diameter larger than that of the inner pin 4, and the inner pin 4 can move so as to revolve in the free fitting hole 32 in a state of being inserted into the free fitting hole 32. Then, the swing component of the planetary gear 3, that is, the revolution component of the planetary gear 3, is absorbed by the loose fitting of the free fitting hole 32 of the planetary gear 3 and the inner pin 4. In other words, the swing component of the planetary gear 3 is absorbed by the plurality of inner pins 4 moving so as to revolve in the plurality of play fitting holes 32, respectively. Therefore, the rotation (rotation component) of the planetary gear 3 excluding the swing component (revolution component) of the planetary gear 3 is transmitted to the inner ring 61 of the bearing member 6 by the plurality of inner pins 4.

By the way, in this type of gear device 1, the rotation of the planetary gear 3 is transmitted to a plurality of inner pins 4 while the inner pin 4 revolves in the clearance hole 32 of the planetary gear 3, and thus, as a first related technique. , It is known to use an inner roller that is mounted on the inner pin 4 and can rotate around the inner pin 4. That is, in the first related technique, the inner pin 4 is held in a state of being press-fitted into the inner ring 61 (or a carrier integrated with the inner ring 61), and the inner pin 4 is held in the loose fitting hole 32. When revolving, the inner pin 4 slides with respect to the inner peripheral surface 321 of the free fitting hole 32. Therefore, as the first related technique, an inner roller is used in order to reduce the loss due to the frictional resistance between the inner peripheral surface 321 of the clearance hole 32 and the inner pin 4. However, in the case of a configuration including an inner roller as in the first related technique, the clearance fitting hole 32 needs to have a diameter at which the inner pin 4 with the inner roller can revolve, and the clearance fitting hole 32 can be downsized. Have difficulty. If it is difficult to reduce the size of the clearance hole 32, it hinders the miniaturization (particularly, the diameter) of the planetary gear 3, which in turn hinders the miniaturization of the entire gear device 1. The gear device 1 according to this basic configuration can provide an inscribed meshing planetary gear device 1 that can be easily miniaturized by the following configuration.

That is, as shown in FIGS. 1 to 3, the gear device 1 according to this basic configuration includes a bearing member 6, an internal gear 2, a planetary gear 3, and a plurality of internal pins 4. The bearing member 6 has an outer ring 62 and an inner ring 61 arranged inside the outer ring 62. The inner ring 61 is rotatably supported relative to the outer ring 62. The internal gear 2 has internal teeth 21 and is fixed to the outer ring 62. The planetary gear 3 has external teeth 31 that partially mesh with the internal teeth 21. The plurality of internal pins 4 rotate relative to the internal gear 2 while revolving in the free fitting holes 32 in a state of being inserted into the plurality of free fitting holes 32 formed in the planetary gear 3. Here, each of the plurality of inner pins 4 is held by the inner ring 61 in a state in which it can rotate. Further, at least a part of each of the plurality of inner pins 4 is arranged at the same position as the bearing member 6 in the axial direction of the bearing member 6.

According to this aspect, since each of the plurality of inner pins 4 is held by the inner ring 61 in a state in which the inner pins 4 can rotate, the inner pins 4 themselves can rotate when the inner pins 4 revolve in the free fitting holes 32. Is. Therefore, even if an inner roller mounted on the inner pin 4 and rotatable about the inner pin 4 is not used, the loss due to the frictional resistance between the inner peripheral surface 321 of the free fitting hole 32 and the inner pin 4 can be reduced. Therefore, the gear device 1 according to the present basic configuration has an advantage that the inner roller is not indispensable and it is easy to miniaturize. Moreover, since at least a part of each of the plurality of inner pins 4 is arranged at the same position as the bearing member 6 in the axial direction of the bearing member 6, the dimension of the gear device 1 in the axial direction of the bearing member 6 can be kept small. Can be done. That is, in the gear device 1 according to this basic configuration, the dimension of the gear device 1 in the axial direction can be made smaller than the configuration in which the bearing member 6 and the inner pin 4 are arranged (opposed) in the axial direction of the bearing member 6. , It is possible to contribute to further miniaturization (thinning) of the gear device 1.

Further, if the dimensions of the planetary gear 3 are the same as those of the first related technique, for example, the number (number) of the inner pins 4 may be increased to smooth the transmission of rotation as compared with the first related technique. It is also possible to increase the strength by thickening the inner pin 4.

Further, in this type of gear device 1, since the inner pin 4 needs to revolve in the free fitting hole 32 of the planetary gear 3, as a second related technique, the plurality of inner pins 4 have the inner ring 61 (or the inner ring 61). It may be held only by the carrier integrated with). According to the second related technique, it is difficult to improve the centering accuracy of the plurality of inner pins 4, and poor centering may lead to problems such as vibration and deterioration of transmission efficiency. That is, each of the plurality of inner pins 4 revolves in the free fitting hole 32 and rotates relative to the internal gear 2, thereby transmitting the rotation component of the planetary gear 3 to the inner ring 61 of the bearing member 6. do. At this time, if the centering accuracy of the plurality of inner pins 4 is insufficient and the rotation axes of the plurality of inner pins 4 are displaced or tilted with respect to the rotation axis of the inner ring 61, a centering failure state occurs. , Vibration may occur, and problems such as a decrease in transmission efficiency may occur. The gear device 1 according to the basic configuration can provide the inscribed meshing planetary gear device 1 which is less likely to cause a defect due to a misalignment of a plurality of inner pins 4 by the following configuration.

That is, as shown in FIGS. 1 to 3, the gear device 1 according to this basic configuration includes an internal gear 2, a planetary gear 3, a plurality of internal pins 4, and a support 8. The internal gear 2 has an annular gear body 22 and a plurality of external pins 23. The plurality of outer pins 23 are held on the inner peripheral surface 221 of the gear body 22 in a state in which they can rotate, and form the inner teeth 21. The planetary gear 3 has external teeth 31 that partially mesh with the internal teeth 21. The plurality of inner pins 4 rotate relative to the gear body 22 while revolving in the free fitting holes 32 in a state of being inserted into the plurality of free fitting holes 32 formed in the planetary gear 3. The support 8 is annular and supports a plurality of inner pins 4. Here, the position of the support 8 is restricted by bringing the outer peripheral surface 81 into contact with the plurality of outer pins 23.

According to this aspect, since the plurality of inner pins 4 are supported by the annular support 8, the plurality of inner pins 4 are bundled by the support 8, and the relative displacements of the plurality of inner pins 4 are obtained. And tilt is suppressed. Moreover, the outer peripheral surface 81 of the support 8 comes into contact with the plurality of outer pins 23, whereby the position of the support 8 is restricted. In short, the support 8 is centered by the plurality of outer pins 23, and as a result, the plurality of inner pins 4 supported by the support 8 are also centered by the plurality of outer pins 23. .. Therefore, according to the gear device 1 according to the present basic configuration, there is an advantage that it is easy to improve the accuracy of centering of the plurality of inner pins 4 and it is less likely that a defect caused by the centering failure of the plurality of inner pins 4 occurs. ..

Further, as shown in FIG. 1, the gear device 1 according to this basic configuration constitutes an actuator 100 together with a drive source 101. In other words, the actuator 100 according to this basic configuration includes a gear device 1 and a drive source 101. The drive source 101 generates a driving force for swinging the planetary gear 3. Specifically, the drive source 101 swings the planetary gear 3 by rotating the eccentric shaft 7 about the rotation shaft Ax1.

(2) Definition The "ring" in the present disclosure means a ring-like shape that forms a space (region) surrounded by the inside, at least in a plan view, and is a perfect circle in a plan view. The shape is not limited to an annular shape (annular shape), and may be, for example, an elliptical shape or a polygonal shape. Further, even if the shape has a bottom such as a cup shape, if the peripheral wall thereof is annular, it is included in the "annular".

The "free fit" referred to in the present disclosure means that the fitting is made in a state having a play (gap), and the free fitting hole 32 is a hole into which the inner pin 4 is loosely fitted. That is, the inner pin 4 is inserted into the free fitting hole 32 in a state where a spatial margin (gap) is secured between the inner pin 4 and the inner peripheral surface 321 of the free fitting hole 32. In other words, the diameter of at least the portion of the inner pin 4 to be inserted into the free fitting hole 32 is smaller (thinner) than the diameter of the free fitting hole 32. Therefore, the inner pin 4 can move in the loose fitting hole 32 in a state of being inserted into the free fitting hole 32, that is, can move relative to the center of the free fitting hole 32. Therefore, the inner pin 4 can revolve in the free fitting hole 32. However, it is not essential to secure a gap as a cavity between the inner peripheral surface 321 of the free fitting hole 32 and the inner pin 4, and for example, even if the gap is filled with a fluid such as a liquid. good.

"Revolution" as used in the present disclosure means that an object orbits around an axis of rotation other than the central axis passing through the center (center of gravity) of the object, and when the object revolves, the center of the object is the axis of rotation. It will move along the revolving orbit centered on. Therefore, for example, when this object rotates about an eccentric axis parallel to the central axis passing through the center (center of gravity) of a certain object, this object revolves around the eccentric axis as the rotation axis. .. As an example, the inner pin 4 revolves in the free fitting hole 32 so as to orbit around a rotation axis passing through the center of the free fitting hole 32.

Further, in the present disclosure, one side of the rotating shaft Ax1 (left side in FIG. 3) may be referred to as an "input side", and the other side of the rotating shaft Ax1 (right side in FIG. 3) may be referred to as an "output side". In the example of FIG. 3, rotation is given to the rotating body (eccentric inner ring 51) from the "input side" of the rotating shaft Ax1, and the rotation of the plurality of inner pins 4 (inner ring 61) is performed from the "output side" of the rotating shaft Ax1. Taken out. However, the "input side" and "output side" are merely labels attached for explanation, and do not mean to limit the positional relationship between the input and the output as seen from the gear device 1.

The "rotational axis" as used in the present disclosure means a virtual axis (straight line) that is the center of the rotational motion of the rotating body. That is, the rotation axis Ax1 is a virtual axis without an entity. The eccentric body ring 51 rotates about the rotation axis Ax1.

The "internal tooth" and "external tooth" referred to in the present disclosure do not mean a single "tooth" but a set (group) of a plurality of "teeth". That is, the internal tooth 21 of the internal gear 2 is composed of a set of a plurality of teeth arranged on the inner peripheral surface 221 of the internal gear 2 (gear body 22). Similarly, the external teeth 31 of the planetary gear 3 are composed of a set of a plurality of teeth arranged on the outer peripheral surface of the planetary gear 3.

(3) Configuration Hereinafter, a detailed configuration of the inscribed meshing planetary gear device 1 according to this basic configuration will be described with reference to FIGS. 1 to 8B.

FIG. 1 is a perspective view showing a schematic configuration of an actuator 100 including a gear device 1. FIG. 1 schematically shows the drive source 101. FIG. 2 is a schematic exploded perspective view of the gear device 1 as viewed from the output side of the rotating shaft Ax1. FIG. 3 is a schematic cross-sectional view of the gear device 1. FIG. 4 is a sectional view taken along line A1-A1 of FIG. However, in FIG. 4, hatching is omitted for parts other than the eccentric shaft 7, even if they are cross sections. Further, in FIG. 4, the illustration of the inner peripheral surface 221 of the gear body 22 is omitted. 5A and 5B are a perspective view and a front view showing the planetary gear 3 as a single substance. 6A and 6B are a perspective view and a front view showing the bearing member 6 as a single unit. 7A and 7B are a perspective view and a front view showing the eccentric shaft 7 as a single unit. 8A and 8B are a perspective view and a front view showing the support 8 as a single unit.

(3.1) Overall configuration As shown in FIGS. 1 to 3, the gear device 1 according to this basic configuration includes an internal gear 2, a planetary gear 3, a plurality of internal pins 4, and an eccentric body bearing 5. , A bearing member 6, an eccentric shaft 7, and a support 8. Further, in the present basic configuration, the gear device 1 further includes a first bearing 91, a second bearing 92, and a case 10. In this basic configuration, the materials of the internal gear 2, the planetary gear 3, the plurality of internal pins 4, the eccentric body bearing 5, the bearing member 6, the eccentric shaft 7, the support 8 and the like, which are the components of the gear device 1, are made of steel. , Cast iron, carbon steel for machine structure, chrome molybdenum steel, phosphorus bronze or metal such as aluminum bronze. The metal referred to here includes a metal that has been subjected to surface treatment such as nitriding treatment.

Further, in this basic configuration, as an example of the gear device 1, an inscribed planetary gear device using a trochoidal tooth profile will be illustrated. That is, the gear device 1 according to this basic configuration includes an inscribed planetary gear 3 having a trochoidal curved tooth profile.

Further, in this basic configuration, as an example, the gear device 1 is used in a state where the gear body 22 of the internal gear 2 is fixed to a fixing member such as a case 10 together with the outer ring 62 of the bearing member 6. As a result, the planetary gear 3 rotates relative to the fixing member (case 10 or the like) as the internal gear 2 and the planetary gear 3 rotate relative to each other.

Further, in this basic configuration, when the gear device 1 is used for the actuator 100, a rotational force as an input is applied to the eccentric shaft 7, so that the rotation as an output is performed from the output shaft integrated with the inner ring 61 of the bearing member 6. The force is taken out. That is, the gear device 1 operates with the rotation of the eccentric shaft 7 as the input rotation and the rotation of the output shaft integrated with the inner ring 61 as the output rotation. As a result, in the gear device 1, the output rotation decelerated at a relatively high reduction ratio with respect to the input rotation can be obtained.

The drive source 101 is a source of power such as a motor (motor). The power generated by the drive source 101 is transmitted to the eccentric shaft 7 in the gear device 1. Specifically, the drive source 101 is connected to the eccentric shaft 7 via the input shaft, and the power generated by the drive source 101 is transmitted to the eccentric shaft 7 via the input shaft. As a result, the drive source 101 can rotate the eccentric shaft 7.

Further, in the gear device 1 according to this basic configuration, as shown in FIG. 3, the rotation shaft Ax1 on the input side and the rotation shaft Ax1 on the output side are on the same straight line. In other words, the rotation axis Ax1 on the input side and the rotation axis Ax1 on the output side are coaxial. Here, the rotation axis Ax1 on the input side is the rotation center of the eccentric shaft 7 to which the input rotation is given, and the rotation axis Ax1 on the output side is the rotation center of the inner ring 61 (and the output shaft) that causes the output rotation. .. That is, in the gear device 1, the output rotation decelerated at a relatively high reduction ratio with respect to the input rotation can be obtained on the same axis.

As shown in FIG. 4, the internal gear 2 is an annular component having internal teeth 21. In this basic configuration, the internal gear 2 has an annular shape in which at least the inner peripheral surface is a perfect circle in a plan view. Internal teeth 21 are formed on the inner peripheral surface of the annular internal gear 2 along the circumferential direction of the internal gear 2. The plurality of teeth constituting the internal tooth 21 all have the same shape, and are provided at equal pitches over the entire area in the circumferential direction on the inner peripheral surface of the internal gear 2. That is, the pitch circle of the internal teeth 21 is a perfect circle in a plan view. The center of the pitch circle of the internal tooth 21 is on the rotation axis Ax1. Further, the internal gear 2 has a predetermined thickness in the direction of the rotating shaft Ax1. The tooth muscles of the internal teeth 21 are all parallel to the axis of rotation Ax1. The dimension of the internal tooth 21 in the tooth muscle direction is slightly smaller than that in the thickness direction of the internal gear 2.

Here, as described above, the internal gear 2 has an annular (annular) gear body 22 and a plurality of external pins 23. The plurality of outer pins 23 are held on the inner peripheral surface 221 of the gear body 22 in a state in which they can rotate, and form the inner teeth 21. In other words, the plurality of external pins 23 each function as a plurality of teeth constituting the internal teeth 21. Specifically, as shown in FIG. 2, a plurality of grooves are formed on the inner peripheral surface 221 of the gear body 22 over the entire circumferential direction. The plurality of grooves all have the same shape and are provided at equal pitches. The plurality of grooves are all parallel to the rotation axis Ax1 and are formed over the entire length of the gear body 22 in the thickness direction. The plurality of outer pins 23 are combined with the gear body 22 so as to fit into the plurality of grooves. Each of the plurality of outer pins 23 is held in a state in which it can rotate in the groove. Further, the gear body 22 is fixed to the case 10 (along with the outer ring 62). Therefore, the gear body 22 is formed with a plurality of fixing holes 222 for fixing.

As shown in FIG. 4, the planetary gear 3 is an annular component having external teeth 31. In this basic configuration, the planetary gear 3 has a shape in which at least the outer peripheral surface is a perfect circle in a plan view. External teeth 31 are formed on the outer peripheral surface of the annular planetary gear 3 along the circumferential direction of the planetary gear 3. The plurality of teeth constituting the external teeth 31 all have the same shape, and are provided at equal pitches on the entire peripheral surface of the planetary gear 3 in the circumferential direction. That is, the pitch circle of the external teeth 31 is a perfect circle in a plan view. The center C1 of the pitch circle of the outer teeth 31 is located at a position deviated from the rotation axis Ax1 by a distance ΔL (see FIG. 4). Further, the planetary gear 3 has a predetermined thickness in the direction of the rotation axis Ax1. The external teeth 31 are all formed over the entire length of the planetary gear 3 in the thickness direction. The tooth muscles of the external teeth 31 are all parallel to the axis of rotation Ax1. In the planetary gear 3, unlike the internal gear 2, the external tooth 31 is integrally formed with the main body of the planetary gear 3 by one metal member.

Here, for the planetary gear 3, the eccentric body bearing 5 and the eccentric shaft 7 are combined. That is, the planetary gear 3 is formed with an opening 33 that opens in a circular shape. The opening 33 is a hole that penetrates the planetary gear 3 along the thickness direction. In a plan view, the center of the opening 33 and the center of the planetary gear 3 coincide with each other, and the inner peripheral surface of the opening 33 (inner peripheral surface of the planetary gear 3) and the pitch circle of the outer teeth 31 are concentric circles. .. The eccentric body bearing 5 is housed in the opening 33 of the planetary gear 3. Further, by inserting the eccentric shaft 7 into the eccentric body bearing 5 (the eccentric body ring 51), the eccentric body bearing 5 and the eccentric shaft 7 are combined with the planetary gear 3. When the eccentric shaft 7 rotates in a state where the eccentric body bearing 5 and the eccentric shaft 7 are combined with the planetary gear 3, the planetary gear 3 swings around the rotating shaft Ax1.

The planetary gear 3 configured in this way is arranged inside the internal gear 2. In a plan view, the planetary gear 3 is formed to be one size smaller than the internal gear 2, and the planetary gear 3 can swing inside the internal gear 2 in a state of being combined with the internal gear 2. Become. Here, the external teeth 31 are formed on the outer peripheral surface of the planetary gear 3, and the internal teeth 21 are formed on the inner peripheral surface of the internal gear 2. Therefore, in the state where the planetary gear 3 is arranged inside the internal gear 2, the external tooth 31 and the internal tooth 21 face each other.

Further, the pitch circle of the outer teeth 31 is one size smaller than the pitch circle of the inner teeth 21. Then, in a state where the planetary gear 3 is inscribed in the internal gear 2, the center C1 of the pitch circle of the external teeth 31 is only a distance ΔL (see FIG. 4) from the center of the pitch circle of the internal teeth 21 (rotation axis Ax1). It is in a misaligned position. Therefore, at least a part of the external tooth 31 and the internal tooth 21 face each other through the gap, and the entire circumferential direction does not mesh with each other. However, since the planetary gear 3 swings (revolves) around the rotation axis Ax1 inside the internal gear 2, the external teeth 31 and the internal teeth 21 partially mesh with each other. That is, as the planetary gear 3 swings around the rotation axis Ax1, as shown in FIG. 4, some of the plurality of teeth constituting the external tooth 31 form a plurality of internal teeth 21. It will mesh with some of the teeth. As a result, in the gear device 1, a part of the outer teeth 31 can be meshed with a part of the inner teeth 21.

Here, the number of teeth of the internal teeth 21 in the internal gear 2 is larger than the number of teeth of the external teeth 31 of the planetary gear 3 by N (N is a positive integer). In this basic configuration, as an example, N is "1", and the number of teeth (of the external teeth 31) of the planetary gear 3 is "1" larger than the number of teeth (of the internal teeth 21) of the internal gear 2. The difference in the number of teeth between the planetary gear 3 and the internal gear 2 defines the reduction ratio of the output rotation to the input rotation in the gear device 1.

Further, in this basic configuration, as an example, the thickness of the planetary gear 3 is smaller than the thickness of the gear body 22 in the internal gear 2. Further, the dimension of the external tooth 31 in the tooth muscle direction (direction parallel to the rotation axis Ax1) is smaller than the dimension of the internal tooth 21 in the tooth muscle direction (direction parallel to the rotation axis Ax1). In other words, in the direction parallel to the rotation axis Ax1, the external tooth 31 fits within the range of the tooth muscle of the internal tooth 21.

In this basic configuration, as described above, the rotation corresponding to the rotation component of the planetary gear 3 is taken out as the rotation (output rotation) of the output shaft integrated with the inner ring 61 of the bearing member 6. Therefore, the planetary gear 3 is connected to the inner ring 61 by a plurality of inner pins 4. As shown in FIGS. 5A and 5B, the planetary gear 3 is formed with a plurality of loose fitting holes 32 for inserting the plurality of inner pins 4. The number of free fitting holes 32 is the same as that of the inner pins 4, and as an example in this basic configuration, 18 free fitting holes 32 and 18 inner pins 4 are provided. Each of the plurality of loose fitting holes 32 is a hole that opens in a circular shape and penetrates the planetary gear 3 along the thickness direction. A plurality of (18 in this case) play fitting holes 32 are arranged at equal intervals in the circumferential direction on a virtual circle concentric with the opening 33.

The plurality of inner pins 4 are parts that connect the planetary gear 3 and the inner ring 61 of the bearing member 6. Each of the plurality of inner pins 4 is formed in a columnar shape. The diameter and length of the plurality of inner pins 4 are common to the plurality of inner pins 4. The diameter of the inner pin 4 is one size smaller than the diameter of the free fitting hole 32. As a result, the inner pin 4 is inserted into the free fitting hole 32 with a spatial margin (gap) secured between the inner pin 4 and the inner peripheral surface 321 of the free fitting hole 32 (see FIG. 4).

The bearing member 6 has an outer ring 62 and an inner ring 61, and is a component for taking out the output of the gear device 1 as the rotation of the inner ring 61 with respect to the outer ring 62. The bearing member 6 has a plurality of rolling elements 63 (see FIG. 3) in addition to the outer ring 62 and the inner ring 61.

As shown in FIGS. 6A and 6B, the outer ring 62 and the inner ring 61 are both annular parts. Both the outer ring 62 and the inner ring 61 have an annular shape that is a perfect circle in a plan view. The inner ring 61 is one size smaller than the outer ring 62 and is arranged inside the outer ring 62. Here, since the inner diameter of the outer ring 62 is larger than the outer diameter of the inner ring 61, a gap is generated between the inner peripheral surface of the outer ring 62 and the outer peripheral surface of the inner ring 61.

The inner ring 61 has a plurality of holding holes 611 into which a plurality of inner pins 4 are inserted. The number of holding holes 611 is the same as that of the inner pins 4, and as an example in this basic configuration, 18 holding holes 611 are provided. As shown in FIGS. 6A and 6B, each of the plurality of holding holes 611 is a hole that opens in a circular shape and penetrates the inner ring 61 along the thickness direction. A plurality of (18 in this case) holding holes 611 are arranged at equal intervals in the circumferential direction on a virtual circle concentric with the outer circumference of the inner ring 61. The diameter of the holding hole 611 is equal to or larger than the diameter of the inner pin 4 and smaller than the diameter of the free fitting hole 32.

Further, the inner ring 61 is integrated with the output shaft, and the rotation of the inner ring 61 is taken out as the rotation of the output shaft. Therefore, the inner ring 61 is formed with a plurality of output-side mounting holes 612 (see FIG. 2) for mounting the output shaft. In this basic configuration, the plurality of output-side mounting holes 612 are arranged on a virtual circle concentric with the outer circumference of the inner ring 61, which is inside the plurality of holding holes 611.

The outer ring 62 is fixed to a fixing member such as a case 10 together with the gear body 22 of the internal gear 2. Therefore, a plurality of through holes 621 for fixing are formed in the outer ring 62. Specifically, as shown in FIG. 3, the outer ring 62 has a fixing screw (bolt) that passes through the through hole 621 and the fixing hole 222 of the gear body 22 with the gear body 22 sandwiched between the outer ring 62 and the case 10. ) 60, fixed to the case 10.

The plurality of rolling elements 63 are arranged in the gap between the outer ring 62 and the inner ring 61. The plurality of rolling elements 63 are arranged side by side in the circumferential direction of the outer ring 62. The plurality of rolling elements 63 are all metal parts having the same shape, and are provided at equal pitches over the entire circumferential direction of the outer ring 62.

As an example in this basic configuration, the bearing member 6 is a cross roller bearing. That is, the bearing member 6 has a cylindrical roller as the rolling element 63. The axis of the cylindrical rolling element 63 has an inclination of 45 degrees with respect to a plane orthogonal to the rotation axis Ax1 and is orthogonal to the outer circumference of the inner ring 61. Further, the pair of rolling elements 63 adjacent to each other in the circumferential direction of the inner ring 61 are arranged in a direction in which the axial directions are orthogonal to each other. In the bearing member 6 made of such a cross roller bearing, it becomes easy to receive any of a load in the radial direction, a load in the thrust direction (direction along the rotating shaft Ax1), and a bending force (bending moment load) with respect to the rotating shaft Ax1. .. Moreover, one bearing member 6 can withstand these three types of loads and can secure the required rigidity.

The eccentric shaft 7 is a cylindrical component, as shown in FIGS. 7A and 7B. The eccentric shaft 7 has an axial center portion 71 and an eccentric portion 72. The axial center portion 71 has a cylindrical shape in which at least the outer peripheral surface is a perfect circle in a plan view. The center (central axis) of the axis center portion 71 coincides with the rotation axis Ax1. The eccentric portion 72 has a disk shape in which at least the outer peripheral surface is a perfect circle in a plan view. The center (central axis) of the eccentric portion 72 coincides with the center C1 deviated from the rotation axis Ax1. Here, the distance ΔL (see FIG. 7B) between the rotation axis Ax1 and the center C1 is the amount of eccentricity of the eccentric portion 72 with respect to the axis center portion 71. The eccentric portion 72 has a flange shape that protrudes from the outer peripheral surface of the axial center portion 71 over the entire circumference at the central portion in the longitudinal direction (axial direction) of the axial center portion 71. According to the above-described configuration, in the eccentric shaft 7, the eccentric portion 72 rotates (rotates) around the rotation shaft Ax1 so that the eccentric portion 72 moves eccentrically.

In this basic configuration, the axial center portion 71 and the eccentric portion 72 are integrally formed of one metal member, whereby a seamless eccentric axis 7 is realized. The eccentric shaft 7 having such a shape is combined with the planetary gear 3 together with the eccentric body bearing 5. Therefore, when the eccentric shaft 7 rotates in a state where the eccentric body bearing 5 and the eccentric shaft 7 are combined with the planetary gear 3, the planetary gear 3 swings around the rotating shaft Ax1.

Further, the eccentric shaft 7 has a through hole 73 that penetrates the shaft center portion 71 in the axial direction (longitudinal direction). The through hole 73 opens in a circular shape on both end faces in the axial direction of the axial center portion 71. The center (central axis) of the through hole 73 coincides with the rotation axis Ax1. Cables such as power lines and signal lines can be passed through the through hole 73, for example.

Further, in this basic configuration, a rotational force as an input is applied to the eccentric shaft 7 from the drive source 101. Therefore, the eccentric shaft 7 is formed with a plurality of input-side mounting holes 74 (see FIGS. 7A and 7B) for mounting the input shaft connected to the drive source 101. In this basic configuration, the plurality of input-side mounting holes 74 are arranged on a virtual circle concentric with the through hole 73, which is around the through hole 73 on one end surface in the axial direction of the axial center portion 71.

The eccentric bearing 5 has an eccentric outer ring 52 and an eccentric inner ring 51, absorbs a rotation component of the rotation of the eccentric shaft 7, and rotates the eccentric shaft 7 excluding the rotation component of the eccentric shaft 7, that is, eccentricity. It is a component for transmitting only the swing component (rotation component) of the shaft 7 to the planetary gear 3. The eccentric body bearing 5 has a plurality of rolling elements 53 (see FIG. 3) in addition to the eccentric body outer ring 52 and the eccentric body ring 51.

The eccentric outer ring 52 and the eccentric inner ring 51 are both annular parts. Both the eccentric outer ring 52 and the eccentric inner ring 51 have an annular shape that is a perfect circle in a plan view. The eccentric inner ring 51 is one size smaller than the eccentric outer ring 52, and is arranged inside the eccentric outer ring 52. Here, since the inner diameter of the eccentric body outer ring 52 is larger than the outer diameter of the eccentric body ring 51, a gap is generated between the inner peripheral surface of the eccentric body outer ring 52 and the outer peripheral surface of the eccentric body ring 51.

The plurality of rolling elements 53 are arranged in the gap between the eccentric outer ring 52 and the eccentric inner ring 51. The plurality of rolling elements 53 are arranged side by side in the circumferential direction of the eccentric body outer ring 52. The plurality of rolling elements 53 are all metal parts having the same shape, and are provided at equal pitches over the entire circumferential direction of the eccentric body outer ring 52. As an example in this basic configuration, the eccentric body bearing 5 is composed of a deep groove ball bearing using a ball as a rolling element 53.

Here, the inner diameter of the eccentric inner ring 51 coincides with the outer diameter of the eccentric portion 72 on the eccentric shaft 7. The eccentric body bearing 5 is combined with the eccentric shaft 7 in a state where the eccentric portion 72 of the eccentric shaft 7 is inserted into the eccentric body ring 51. Further, the outer diameter of the eccentric body outer ring 52 coincides with the inner diameter (diameter) of the opening 33 in the planetary gear 3. The eccentric body bearing 5 is combined with the planetary gear 3 in a state where the eccentric body outer ring 52 is fitted in the opening 33 of the planetary gear 3. In other words, the opening 33 of the planetary gear 3 accommodates the eccentric body bearing 5 mounted on the eccentric portion 72 of the eccentric shaft 7.

Further, as an example in this basic configuration, the dimension in the width direction (direction parallel to the rotation axis Ax1) of the eccentric body ring 51 in the eccentric body bearing 5 is substantially the same as the thickness of the eccentric portion 72 of the eccentric shaft 7. The width direction of the eccentric body outer ring 52 (direction parallel to the rotation axis Ax1) is slightly smaller than the width direction of the eccentric body ring 51. Further, the widthwise dimension of the eccentric outer ring 52 is larger than the thickness of the planetary gear 3. Therefore, in the direction parallel to the rotation shaft Ax1, the planetary gear 3 fits within the range of the eccentric body bearing 5. On the other hand, the dimension in the width direction of the eccentric body outer ring 52 is smaller than the dimension in the tooth muscle direction (direction parallel to the rotation axis Ax1) of the internal tooth 21. Therefore, in the direction parallel to the rotation shaft Ax1, the eccentric body bearing 5 fits within the range of the internal gear 2.

When the eccentric shaft 7 rotates while the eccentric body bearing 5 and the eccentric shaft 7 are combined with the planetary gear 3, in the eccentric body bearing 5, the eccentric body bearing 5 is placed in the eccentric body around the rotation shaft Ax1 deviated from the center C1 of the eccentric body ring 51. The wheel 51 rotates (eccentric movement). At this time, the rotation component of the eccentric shaft 7 is absorbed by the eccentric body bearing 5. Therefore, the eccentric body bearing 5 transmits only the rotation of the eccentric shaft 7 excluding the rotation component of the eccentric shaft 7, that is, the swing component (revolution component) of the eccentric shaft 7. Therefore, when the eccentric shaft 7 rotates in a state where the eccentric body bearing 5 and the eccentric shaft 7 are combined with the planetary gear 3, the planetary gear 3 swings around the rotating shaft Ax1.

As shown in FIGS. 8A and 8B, the support 8 is a component that is formed in an annular shape and supports a plurality of inner pins 4. The support 8 has a plurality of support holes 82 into which the plurality of inner pins 4 are inserted. The number of support holes 82 is the same as that of the inner pins 4, and 18 support holes 82 are provided as an example in this basic configuration. As shown in FIGS. 8A and 8B, each of the plurality of support holes 82 is a hole that opens in a circular shape and penetrates the support 8 along the thickness direction. A plurality of (18 in this case) support holes 82 are arranged at equal intervals in the circumferential direction on a virtual circle concentric with the outer peripheral surface 81 of the support body 8. The diameter of the support hole 82 is equal to or larger than the diameter of the inner pin 4 and smaller than the diameter of the free fitting hole 32. As an example in this basic configuration, the diameter of the support hole 82 is equal to the diameter of the holding hole 611 formed in the inner ring 61.

As shown in FIG. 3, the support 8 is arranged so as to face the planetary gear 3 from one side (input side) of the rotation shaft Ax1. Then, by inserting the plurality of inner pins 4 into the plurality of support holes 82, the support 8 functions to bundle the plurality of inner pins 4. Further, the position of the support 8 is restricted by bringing the outer peripheral surface 81 into contact with the plurality of outer pins 23. As a result, the support 8 is centered by the plurality of outer pins 23, and as a result, the plurality of inner pins 4 supported by the support 8 are also centered by the plurality of outer pins 23. Will be. The support 8 will be described in detail in the column of “(3.3) Support”.

The first bearing 91 and the second bearing 92 are respectively mounted on the axial center portion 71 of the eccentric shaft 7. Specifically, as shown in FIG. 3, the first bearing 91 and the second bearing 92 are placed on both sides of the eccentric portion 72 in the axial center portion 71 so as to sandwich the eccentric portion 72 in the direction parallel to the rotation axis Ax1. It will be installed. The first bearing 91 is arranged on the input side of the rotation shaft Ax1 when viewed from the eccentric portion 72. The second bearing 92 is arranged on the output side of the rotating shaft Ax1 when viewed from the eccentric portion 72. The first bearing 91 rotatably holds the eccentric shaft 7 with respect to the case 10. The second bearing 92 rotatably holds the eccentric shaft 7 with respect to the inner ring 61 of the bearing member 6. As a result, the axial center portion 71 of the eccentric shaft 7 is rotatably held at two locations on both sides of the eccentric portion 72 in the direction parallel to the rotation axis Ax1.

The case 10 has a cylindrical shape and has a flange portion 11 on the output side of the rotating shaft Ax1. A plurality of installation holes 111 for fixing the case 10 itself are formed in the flange portion 11. Further, a bearing hole 12 is formed on the end surface of the rotation shaft Ax1 on the output side of the case 10. The bearing hole 12 is open in a circular shape. By fitting the first bearing 91 into the bearing hole 12, the first bearing 91 is attached to the case 10.

Further, a plurality of screw holes 13 are formed around the bearing hole 12 on the output side end surface of the rotary shaft Ax1 in the case 10. The plurality of screw holes 13 are used to fix the gear body 22 of the internal gear 2 and the outer ring 62 of the bearing member 6 to the case 10. Specifically, the fixing screw 60 is tightened to the screw hole 13 through the through hole 621 of the outer ring 62 and the fixing hole 222 of the gear body 22, so that the gear body 22 and the outer ring 62 are fixed to the case 10. Will be done.

Further, as shown in FIG. 3, the gear device 1 according to this basic configuration further includes a plurality of oil seals 14, 15, 16, and the like. The oil seal 14 is attached to the end of the eccentric shaft 7 on the input side of the rotating shaft Ax1 and closes the gap between the case 10 and the eccentric shaft 7 (axis center portion 71). The oil seal 15 is attached to the output-side end of the rotating shaft Ax1 on the eccentric shaft 7 and closes the gap between the inner ring 61 and the eccentric shaft 7 (axis center portion 71). The oil seal 16 is attached to the end surface of the bearing member 6 on the output side of the rotating shaft Ax1 and closes the gap between the inner ring 61 and the outer ring 62. The space sealed by the plurality of oil seals 14, 15 and 16 constitutes the lubricant holding space 17 (see FIG. 9). The lubricant holding space 17 includes a space between the inner ring 61 and the outer ring 62 of the bearing member 6. Further, a plurality of outer pins 23, planetary gears 3, eccentric body bearings 5, supports 8, first bearing 91, second bearing 92 and the like are housed in the lubricant holding space 17.

Then, the lubricant is injected into the lubricant holding space 17. The lubricant is a liquid and can flow in the lubricant holding space 17. Therefore, when the gear device 1 is used, for example, the lubricant enters the meshing portion between the internal tooth 21 composed of the plurality of external pins 23 and the external tooth 31 of the planetary gear 3. The "liquid" as used in the present disclosure includes a liquid or gel-like substance. The term "gel-like" as used herein means a state having properties intermediate between a liquid and a solid, and includes a colloidal state consisting of two phases, a liquid phase and a solid phase. For example, a state called gel or sol, such as an emulsion in which the dispersion medium is a liquid phase and the dispersoid is a liquid phase, and a suspension in which the dispersoid is a solid phase, is present. Included in "gel". Further, a state in which the dispersion medium is a solid phase and the dispersoid is a liquid phase is also included in the “gel state”. As an example in this basic configuration, the lubricant is a liquid lubricating oil (oil).

In the gear device 1 having the above-described configuration, a rotational force as an input is applied to the eccentric shaft 7, and the eccentric shaft 7 rotates about the rotary shaft Ax1, so that the planetary gear 3 swings around the rotary shaft Ax1. (Revolve). At this time, the planetary gear 3 is inscribed with respect to the internal tooth gear 2 inside the internal gear 2, and swings in a state where a part of the external tooth 31 meshes with a part of the internal tooth 21. The meshing position between the 21 and the external tooth 31 moves in the circumferential direction of the internal gear 2. As a result, relative rotation corresponding to the difference in the number of teeth between the planetary gear 3 and the internal gear 2 is generated between the two gears (internal gear 2 and the planetary gear 3). Then, the rotation (rotation component) of the planetary gear 3 excluding the swing component (revolution component) of the planetary gear 3 is transmitted to the inner ring 61 of the bearing member 6 by the plurality of inner pins 4. As a result, from the output shaft integrated with the inner ring 61, a rotational output decelerated at a relatively high reduction ratio can be obtained according to the difference in the number of teeth of both gears.

By the way, in the gear device 1 according to the present embodiment, as described above, the difference in the number of teeth between the internal gear 2 and the planetary gear 3 defines the reduction ratio of the output rotation to the input rotation in the gear device 1. become. That is, when the number of teeth of the internal gear 2 is "V1" and the number of teeth of the planetary gear 3 is "V2", the reduction ratio R1 is expressed by the following equation 1.

R1 = V2 / (V1-V2) ... (Equation 1)
In short, the smaller the difference in the number of teeth (V1-V2) between the internal gear 2 and the planetary gear 3, the larger the reduction ratio R1. As an example, the number of teeth V1 of the internal gear 2 is "52", the number of teeth V2 of the planetary gear 3 is "51", and the difference in the number of teeth (V1-V2) is "1". The reduction ratio R1 is "51". In this case, when the eccentric axis 7 rotates once clockwise (360 degrees) around the rotation axis Ax1 when viewed from the input side of the rotation axis Ax1, the inner ring 61 has a tooth number difference "1" about the rotation axis Ax1. Rotate counterclockwise by the minute (that is, about 7.06 degrees).

According to the gear device 1 according to this basic configuration, such a high reduction ratio R1 can be realized by a combination of one-stage gears (internal gear 2 and planetary gear 3).

Further, the gear device 1 may include at least an internal gear 2, a planetary gear 3, a plurality of internal pins 4, a bearing member 6, and a support 8, for example, a spline bush or the like. It may be further provided as a component.

By the way, when the input rotation on the high-speed rotation side is accompanied by eccentric motion as in the gear device 1 according to this basic configuration, if the weight of the rotating body rotating at high speed is not balanced, it may lead to vibration or the like. Therefore, the weight may be balanced by using a counter weight or the like. That is, since the rotating body composed of at least one of the eccentric body ring 51 and the member (eccentric axis 7) rotating together with the eccentric body ring 51 moves eccentrically at high speed, it is possible to balance the weight of the rotating body with respect to the rotation axis Ax1. preferable. In this basic configuration, as shown in FIGS. 3 and 4, the weight of the rotating body is balanced with respect to the rotating shaft Ax1 by providing a gap 75 in a part of the eccentric portion 72 in the eccentric shaft 7.

In short, in this basic configuration, instead of adding a counter weight or the like, a part of the rotating body (here, the eccentric shaft 7) is lightened to reduce the weight, thereby balancing the weight of the rotating body with respect to the rotating shaft Ax1. I'm taking it. That is, the gear device 1 according to this basic configuration is housed in the opening 33 formed in the planetary gear 3, and includes an eccentric body bearing 5 that swings the planetary gear 3. The eccentric body bearing 5 has an eccentric body outer ring 52 and an eccentric body ring 51 arranged inside the eccentric body outer ring 52. The rotating body composed of at least one of the eccentric body ring 51 and the member rotating together with the eccentric body ring 51 has a gap 75 in a part of the eccentric body outer ring 52 on the center C1 side when viewed from the rotation axis Ax1 of the eccentric body ring 51. .. In this basic configuration, the eccentric shaft 7 is a "member that rotates together with the eccentric body ring 51" and corresponds to a "rotating body". Therefore, the void 75 formed in the eccentric portion 72 of the eccentric shaft 7 corresponds to the void 75 of the rotating body. As shown in FIGS. 3 and 4, the gap 75 is located on the center C1 side when viewed from the rotation axis Ax1, so that the weight balance of the eccentric axis 7 is evenly approached in the circumferential direction from the rotation axis Ax1. It works.

More specifically, the void 75 includes a recess formed in the inner peripheral surface of the through hole 73 penetrating the rotating body along the rotation axis Ax1 of the eccentric body ring 51. That is, in this basic configuration, since the rotating body is the eccentric shaft 7, the recess formed on the inner peripheral surface of the through hole 73 penetrating the eccentric shaft 7 along the rotating shaft Ax1 functions as the void 75. By using the recess formed on the inner peripheral surface of the through hole 73 as the gap 75 in this way, it is possible to balance the weight of the rotating body without changing the appearance.

(3.2) Rotational Structure of Inner Pin Next, the rotation structure of the inner pin 4 of the gear device 1 according to this basic configuration will be described in more detail with reference to FIG. FIG. 9 is an enlarged view of the region Z1 of FIG.

First, as a premise, the plurality of inner pins 4 are parts that connect the planetary gear 3 and the inner ring 61 of the bearing member 6 as described above. Specifically, one end of the inner pin 4 in the longitudinal direction (in this basic configuration, the end on the input side of the rotating shaft Ax1) is inserted into the free fitting hole 32 of the planetary gear 3 and is in the longitudinal direction of the inner pin 4. The other end portion (the end portion on the output side of the rotating shaft Ax1 in this basic configuration) is inserted into the holding hole 611 of the inner ring 61.

Here, since the diameter of the inner pin 4 is one size smaller than the diameter of the free fitting hole 32, a gap is secured between the inner pin 4 and the inner peripheral surface 321 of the free fitting hole 32, and the inner pin 4 has an inner pin 4. , It is movable in the free fitting hole 32, that is, it is movable relative to the center of the free fitting hole 32. On the other hand, the diameter of the holding hole 611 is smaller than the diameter of the free fitting hole 32, although it is larger than the diameter of the inner pin 4. In this basic configuration, the diameter of the holding hole 611 is substantially the same as the diameter of the inner pin 4, and is slightly larger than the diameter of the inner pin 4. Therefore, the movement of the inner pin 4 in the holding hole 611 is restricted, that is, the movement relative to the center of the holding hole 611 is prohibited. Therefore, the inner pin 4 is held in the free-rotating hole 32 in the planetary gear 3 in a revolving state, and is held in the holding hole 611 in a non-revolving state for the inner ring 61. As a result, the swing component of the planetary gear 3, that is, the revolution component of the planetary gear 3, is absorbed by the loose fitting between the free fitting hole 32 and the inner pin 4, and the inner ring 61 has the planetary gear by the plurality of inner pins 4. The rotation (rotation component) of the planetary gear 3 excluding the swing component (revolution component) of 3 is transmitted.

By the way, in this basic configuration, since the diameter of the inner pin 4 is slightly larger than that of the holding hole 611, the inner pin 4 is prohibited from revolving in the holding hole 611 when it is inserted into the holding hole 611. However, it is possible to rotate in the holding hole 611. That is, the inner pin 4 is not press-fitted into the holding hole 611 even when it is inserted into the holding hole 611, so that the inner pin 4 can rotate in the holding hole 611. As described above, in the gear device 1 according to the present basic configuration, each of the plurality of inner pins 4 is held by the inner ring 61 in a state in which the inner pins 4 can rotate, so that when the inner pins 4 revolve in the free fitting holes 32, the inner pins 4 revolve. , The inner pin 4 itself can rotate.

In short, in this basic configuration, the inner pin 4 is held in a state where both the planetary gear 3 can revolve and rotate in the free fitting hole 32, and the inner ring 61 is held in the holding hole 611. It is held in a state where it can only rotate on its axis. That is, the plurality of inner pins 4 can rotate (revolve) about the rotation axis Ax1 in a state where their rotation is not restrained (rotation possible state), and can revolve in the plurality of idle fitting holes 32. Is. Therefore, when the rotation (rotation component) of the planetary gear 3 is transmitted to the inner ring 61 by the plurality of inner pins 4, the inner pins 4 revolve and rotate in the free fitting hole 32 and in the holding hole 611. Can rotate. Therefore, when the inner pin 4 revolves in the free fitting hole 32, the inner pin 4 is in a state where it can rotate, so that the inner pin 4 rolls with respect to the inner peripheral surface 321 of the free fitting hole 32. In other words, since the inner pin 4 revolves in the free fitting hole 32 so as to roll on the inner peripheral surface 321 of the free fitting hole 32, the inner pin 4 is between the inner peripheral surface 321 of the free fitting hole 32 and the inner pin 4. Loss due to frictional resistance is unlikely to occur.

As described above, in the configuration according to this basic configuration, loss due to frictional resistance between the inner peripheral surface 321 of the free fitting hole 32 and the inner pin 4 is unlikely to occur, so that the inner roller can be omitted. Therefore, in this basic configuration, each of the plurality of inner pins 4 adopts a configuration in which the inner peripheral surface 321 of the free fitting hole 32 is in direct contact with each other. That is, in this basic configuration, the inner pin 4 in the state where the inner roller is not mounted is inserted into the free fitting hole 32, and the inner pin 4 directly contacts the inner peripheral surface 321 of the free fitting hole 32. .. As a result, the inner roller can be omitted and the diameter of the free fitting hole 32 can be kept relatively small, so that the planetary gear 3 can be miniaturized (particularly small in diameter), and the gear device 1 as a whole can be miniaturized. It will be easier to plan. If the dimensions of the planetary gear 3 are constant, for example, the number (number) of the inner pins 4 may be increased to make the rotation transmission smoother, or the inner pins 4 may be made thicker, as compared with the first related technique. It is also possible to improve the strength. Further, the number of parts can be reduced by the amount of the inner roller, which leads to the cost reduction of the gear device 1.

Further, in the gear device 1 according to the present basic configuration, at least a part of each of the plurality of inner pins 4 is arranged at the same position as the bearing member 6 in the axial direction of the bearing member 6. That is, as shown in FIG. 9, at least a part of the inner pin 4 is arranged at the same position as the bearing member 6 in the direction parallel to the rotation axis Ax1. In other words, at least a part of the inner pin 4 is located between both end faces of the bearing member 6 in the direction parallel to the rotation axis Ax1. In other words, at least a part of each of the plurality of inner pins 4 is arranged inside the outer ring 62 of the bearing member 6. In this basic configuration, the end of the inner pin 4 on the output side of the rotating shaft Ax1 is at the same position as the bearing member 6 in the direction parallel to the rotating shaft Ax1. In short, since the output-side end of the rotation shaft Ax1 of the inner pins 4 is inserted into the holding hole 611 formed in the inner ring 61 of the bearing member 6, at least the end is the shaft of the bearing member 6. It will be arranged at the same position as the bearing member 6 in the direction.

In this way, at least a part of each of the plurality of inner pins 4 is arranged at the same position as the bearing member 6 in the axial direction of the bearing member 6, so that the dimensions of the gear device 1 in the direction parallel to the rotating shaft Ax1 Can be kept small. That is, compared to the configuration in which the bearing member 6 and the inner pin 4 are arranged (opposed) in the axial direction of the bearing member 6, in the gear device 1 according to this basic configuration, the gear device 1 in the direction parallel to the rotating shaft Ax1. It is possible to reduce the size of the gear device 1 and contribute to further miniaturization (thinning) of the gear device 1.

Here, the opening surface on the output side of the rotation shaft Ax1 in the holding hole 611 is closed by, for example, an output shaft integrated with the inner ring 61. As a result, the movement of the inner pin 4 to the output side (right side in FIG. 9) of the rotating shaft Ax1 is regulated by the output shaft integrated with the inner ring 61 or the like.

Further, in this basic configuration, the following configuration is adopted so that the inner pin 4 rotates smoothly with respect to the inner ring 61. That is, by interposing a lubricant (lubricating oil) between the inner peripheral surface of the holding hole 611 formed in the inner ring 61 and the inner pin 4, the rotation of the inner pin 4 is smoothed. In particular, in this basic configuration, since the lubricant holding space 17 into which the lubricant is injected exists between the inner ring 61 and the outer ring 62, the lubricant in the lubricant holding space 17 is used to form the inner pin 4. Smooth rotation.

In this basic configuration, as shown in FIG. 9, the inner ring 61 has a plurality of holding holes 611 into which a plurality of inner pins 4 are inserted, and a plurality of connecting paths 64. The plurality of connecting paths 64 connect between the lubricant holding space 17 between the inner ring 61 and the outer ring 62 and the plurality of holding holes 611. Specifically, the inner ring 61 is formed with a connecting path 64 extending in the radial direction from a portion of the inner peripheral surface of the holding hole 611 and corresponding to the rolling element 63. The connecting path 64 is a hole penetrating between the bottom surface of the recess (groove) accommodating the rolling element 63 on the surface facing the outer ring 62 of the inner ring 61 and the inner peripheral surface of the holding hole 611. In other words, the opening surface of the connecting path 64 on the lubricant holding space 17 side is arranged at a position facing (opposing) the rolling element 63 of the bearing member 6. The lubricant holding space 17 and the holding hole 611 are spatially connected via such a connecting path 64.

According to the above-described configuration, since the lubricant holding space 17 and the holding hole 611 are connected by the connecting path 64, the lubricant in the lubricant holding space 17 is supplied to the holding hole 611 through the connecting path 64. become. That is, when the bearing member 6 operates and the rolling element 63 rotates, the rolling element 63 functions as a pump, and the lubricant in the lubricant holding space 17 can be sent to the holding hole 611 via the connecting path 64. Is. In particular, since the opening surface of the connecting path 64 on the lubricant holding space 17 side is located at a position facing (opposing) the rolling element 63 of the bearing member 6, the rolling element 63 is efficient as a pump when the rolling element 63 rotates. Acts as a target. As a result, a lubricant is interposed between the inner peripheral surface of the holding hole 611 and the inner pin 4, and the rotation of the inner pin 4 with respect to the inner ring 61 can be facilitated.

(3.3) Support Next, the configuration of the support 8 of the gear device 1 according to this basic configuration will be described in more detail with reference to FIG. FIG. 10 is a sectional view taken along line B1-B1 of FIG. However, in FIG. 10, hatching is omitted for the parts other than the support 8 even if they are cross sections. Further, in FIG. 10, only the internal gear 2 and the support 8 are shown, and the illustration of other parts (inner pin 4, etc.) is omitted. Further, in FIG. 10, the illustration of the inner peripheral surface 221 of the gear body 22 is omitted.

First, as a premise, the support 8 is a component that supports a plurality of inner pins 4 as described above. That is, the support 8 distributes the load applied to the plurality of inner pins 4 when transmitting the rotation (rotation component) of the planetary gear 3 to the inner ring 61 by bundling the plurality of inner pins 4. Specifically, it has a plurality of support holes 82 into which a plurality of inner pins 4 are inserted. As an example in this basic configuration, the diameter of the support hole 82 is equal to the diameter of the holding hole 611 formed in the inner ring 61. Therefore, the support 8 supports the plurality of inner pins 4 in a state where each of the plurality of inner pins 4 can rotate. That is, each of the plurality of inner pins 4 is held in a state in which it can rotate with respect to both the inner ring 61 and the support 8 of the bearing member 6.

In this way, the support 8 positions the plurality of inner pins 4 with respect to the support 8 in both the circumferential direction and the radial direction. That is, by inserting the inner pin 4 into the support hole 82 of the support body 8, movement in all directions in a plane orthogonal to the rotation axis Ax1 is restricted. Therefore, the inner pin 4 is positioned not only in the circumferential direction but also in the radial direction (radial direction) by the support 8.

Here, the support 8 has an annular shape in which at least the outer peripheral surface 81 is a perfect circle in a plan view. The position of the support 8 is restricted by bringing the outer peripheral surface 81 into contact with the plurality of outer pins 23 of the internal gear 2. Since the plurality of external pins 23 constitute the internal teeth 21 of the internal gear 2, in other words, the support 8 is positioned by bringing the outer peripheral surface 81 into contact with the internal teeth 21. Here, the diameter of the outer peripheral surface 81 of the support 8 is the same as the diameter of the virtual circle (tooth tip circle) passing through the tip of the internal tooth 21 in the internal gear 2. Therefore, the plurality of outer pins 23 all come into contact with the outer peripheral surface 81 of the support 8. Therefore, in a state where the support 8 is position-restricted by the plurality of outer pins 23, the center of the support 8 is position-restricted so as to overlap the center of the internal gear 2 (rotational shaft Ax1). As a result, the support 8 is centered, and as a result, the plurality of inner pins 4 supported by the support 8 are also centered by the plurality of outer pins 23.

Further, the plurality of inner pins 4 rotate (revolve) around the rotation axis Ax1 to transmit the rotation (rotation component) of the planetary gear 3 to the inner ring 61. Therefore, the support 8 that supports the plurality of inner pins 4 rotates about the rotation axis Ax1 together with the plurality of inner pins 4 and the inner ring 61. At this time, since the support 8 is centered by the plurality of outer pins 23, the support 8 rotates smoothly while the center of the support 8 is maintained on the rotation axis Ax1. Moreover, since the support 8 rotates in a state where the outer peripheral surface 81 is in contact with the plurality of outer pins 23, each of the plurality of outer pins 23 rotates (rotates) with the rotation of the support 8. Therefore, the support 8 constitutes a needle bearing (needle-shaped roller bearing) together with the internal gear 2 and rotates smoothly.

That is, the outer peripheral surface 81 of the support 8 rotates relative to the gear body 22 together with the plurality of inner pins 4 in a state of being in contact with the plurality of outer pins 23. Therefore, if the gear body 22 of the internal gear 2 is regarded as an "outer ring" and the support 8 is regarded as an "inner ring", the plurality of outer pins 23 interposed between the two functions as "rolling bodies (rollers)". In this way, the support 8 constitutes a needle bearing together with the internal gear 2 (the gear body 22 and the plurality of external pins 23), and smooth rotation is possible.

Further, since the support 8 sandwiches the plurality of outer pins 23 with the gear body 22, the support 8 suppresses the movement of the outer pins 23 in the direction away from the inner peripheral surface 221 of the gear body 22. It also functions as a "stopper". That is, the plurality of outer pins 23 are sandwiched between the outer peripheral surface 81 of the support 8 and the inner peripheral surface 221 of the gear body 22, and the floating of the gear body 22 from the inner peripheral surface 221 is suppressed. .. In short, in this basic configuration, each of the plurality of outer pins 23 is restricted from moving away from the gear body 22 by coming into contact with the outer peripheral surface 81 of the support 8.

By the way, in this basic configuration, as shown in FIG. 9, the support 8 is located on the side opposite to the inner ring 61 of the bearing member 6 with the planetary gear 3 interposed therebetween. That is, the support 8, the planetary gear 3, and the inner ring 61 are arranged side by side in the direction parallel to the rotation axis Ax1. In this basic configuration, as an example, the support 8 is located on the input side of the rotary shaft Ax1 when viewed from the planetary gear 3, and the inner ring 61 is located on the output side of the rotary shaft Ax1 when viewed from the planetary gear 3. Then, the support 8 supports both ends of the inner pin 4 in the longitudinal direction (direction parallel to the rotation axis Ax1) together with the inner ring 61, and the central portion of the inner pin 4 in the longitudinal direction is the loose fitting of the planetary gear 3. It is inserted through the hole 32. In short, the gear device 1 according to this basic configuration has an outer ring 62 and an inner ring 61 arranged inside the outer ring 62, and a bearing member 6 in which the inner ring 61 is rotatably supported relative to the outer ring 62. I have. Then, the gear body 22 is fixed to the outer ring 62. Here, the planetary gear 3 is located between the support 8 and the inner ring 61 in the axial direction of the support 8.

According to this configuration, since the support 8 and the inner ring 61 support both ends of the inner pin 4 in the longitudinal direction, the inner pin 4 is less likely to be tilted. In particular, it becomes easy to receive a bending force (bending moment load) with respect to the rotating shaft Ax1 applied to the plurality of inner pins 4. Further, in this basic configuration, the support 8 is sandwiched between the planetary gear 3 and the case 10 in a direction parallel to the rotation axis Ax1. As a result, the support 8 is restricted from moving to the input side (left side in FIG. 9) of the rotation axis Ax1 in the case 10. The inner pin 4 that penetrates the support hole 82 of the support 8 and protrudes from the support 8 to the input side of the rotary shaft Ax1 is also moved to the input side of the rotary shaft Ax1 (left side in FIG. 9) in the case 10. Is regulated.

Further, in this basic configuration, the support 8 and the inner ring 61 come into contact with both ends of the plurality of outer pins 23. That is, as shown in FIG. 9, the support 8 comes into contact with one end (the end on the input side of the rotation axis Ax1) in the longitudinal direction (direction parallel to the rotation axis Ax1) of the outer pin 23. The inner ring 61 contacts the other end of the outer pin 23 in the longitudinal direction (direction parallel to the rotation axis Ax1) (the end on the output side of the rotation axis Ax1). According to this configuration, since the support 8 and the inner ring 61 are centered at both ends of the outer pin 23 in the longitudinal direction, the inner pin 4 is less likely to be tilted. In particular, it becomes easy to receive a bending force (bending moment load) with respect to the rotating shaft Ax1 applied to the plurality of inner pins 4.

Further, the plurality of outer pins 23 have a length equal to or larger than the thickness of the support 8. In other words, in the direction parallel to the rotation axis Ax1, the support 8 fits within the range of the tooth muscle of the internal tooth 21. As a result, the outer peripheral surface 81 of the support 8 comes into contact with the plurality of outer pins 23 over the entire length of the inner teeth 21 in the tooth muscle direction (direction parallel to the rotation axis Ax1). Therefore, a problem such as "one-sided reduction" in which the outer peripheral surface 81 of the support 8 is partially worn is unlikely to occur.

Further, in this basic configuration, the outer peripheral surface 81 of the support 8 has a smaller surface roughness than one surface adjacent to the outer peripheral surface 81 of the support 8. That is, the surface roughness of the outer peripheral surface 81 is smaller than that of both end surfaces in the axial direction (thickness direction) of the support 8. The "surface roughness" referred to in the present disclosure means the degree of surface roughness of an object, and the smaller the value, the smaller (less) the unevenness of the surface and the smoother the surface. In this basic configuration, as an example, the surface roughness is an arithmetic mean roughness (Ra). For example, by a treatment such as polishing, the outer peripheral surface 81 has a smaller surface roughness than the surfaces other than the outer peripheral surface 81 of the support 8. In this configuration, the rotation of the support 8 becomes smoother.

Further, in this basic configuration, the hardness of the outer peripheral surface 81 of the support 8 is lower than the peripheral surface of the plurality of outer pins 23 and higher than the inner peripheral surface 221 of the gear body 22. The "hardness" in the present disclosure means the degree of hardness of an object, and the hardness of a metal is represented by, for example, the size of a dent formed by pressing a steel ball with a constant pressure. Specifically, examples of metal hardness include Rockwell hardness (HRC), Brinell hardness (HB), Vickers hardness (HV), shore hardness (Hs), and the like. As a means for increasing (hardening) the hardness of a metal part, for example, alloying or heat treatment is used. In this basic configuration, as an example, the hardness of the outer peripheral surface 81 of the support 8 is increased by a treatment such as charcoal burning. In this configuration, wear debris and the like are less likely to be generated by the rotation of the support 8, and it is easy to maintain the smooth rotation of the support 8 for a long period of time.

(4) Application Example Next, an application example of the gear device 1 and the actuator 100 according to this basic configuration will be described.

The gear device 1 and the actuator 100 according to this basic configuration are applied to a robot such as a horizontal articulated robot, a so-called SCARA (Selective Compliance Assembly Robot Arm) type robot.

Further, the application example of the gear device 1 and the actuator 100 according to this basic configuration is not limited to the horizontal articulated robot as described above, and is, for example, an industrial robot other than the horizontal articulated robot, a robot other than the industrial robot, or the like. There may be. Examples of industrial robots other than horizontal articulated robots include vertical articulated robots and parallel link robots. Examples of non-industrial robots include domestic robots, nursing robots, medical robots, and the like.

(Embodiment 1)
<Overview>
As shown in FIGS. 11 to 14, the structure around the bearing member 6A mainly relates to the basic configuration of the inscribed meshing planetary gear device 1A (hereinafter, also simply referred to as “gear device 1A”) according to the present embodiment. It is different from the gear device 1. Hereinafter, the same configurations as the basic configurations will be designated by common reference numerals and description thereof will be omitted as appropriate.

FIG. 11 is a schematic cross-sectional view of the gear device 1A. FIG. 12 is a side view of the gear device 1A as viewed from the output side (right side of FIG. 11) of the rotating shaft Ax1, and FIG. 11 corresponds to a cross-sectional view taken along the line C1-C1 of FIG. 13 is a sectional view taken along line A1-A1 of FIG. 11, and FIG. 14 is a sectional view taken along line B1-B1 of FIG. 11 and a partially enlarged view thereof. However, in FIGS. 13 and 14, hatching is omitted even in the cross section of the parts other than the eccentric shaft 7.

In the present embodiment, the bearing member 6A has an outer ring 62A, an inner ring 61A arranged inside the outer ring 62A, and a plurality of rolling elements 63 arranged between the outer ring 62A and the inner ring 61A. Then, the inner ring 61A is rotatably supported with respect to the outer ring 62A about the rotation axis Ax1. This point is the same as the basic configuration.

The first main difference from the basic configuration of the gear device 1A according to the present embodiment is that the inner ring 61A of the bearing member 6A is not composed of one component, but the first inner ring 601 and the second inner ring. It is configured to include two parts with 602. That is, as shown in FIG. 11, in the gear device 1A, the inner ring 61A faces the first inner ring 601 in a direction parallel to the rotation axis Ax1 and the facing surfaces 601A, 602A (see FIG. 15) come into contact with each other. The second inner ring 602 is included.

The second main difference from the basic configuration of the gear device 1A according to the present embodiment is that the outer ring 62A of the bearing member 6A is configured separately from the gear body 22 of the internal gear 2. It is seamlessly integrated with the gear body 22. That is, as shown in FIG. 11, in the gear device 1A, the outer ring 62A is seamlessly and continuously provided in the direction parallel to the gear body 22 and the rotation axis Ax1 (the tooth muscle direction of the internal teeth 21).

In short, the gear device 1A according to the present embodiment newly adopts a device for the inner ring 61A of the bearing member 6A and a device for the outer ring 62A of the bearing member 6A as the main differences from the basic configuration. There is. The device for the inner ring 61A includes that the inner ring 61A has the first inner ring 601 and the second inner ring 602, and the device for the outer ring 62A includes that the outer ring 62 is seamlessly and continuously provided with the gear body 22.

<Other differences>
In the gear device 1A according to the present embodiment, in addition to the main differences described above (ingenuity for the inner ring 61A and ingenuity for the outer ring 62A), as described below, a plurality of gear devices 1A have a plurality of basic configurations. There are differences.

As another first difference, the gear device 1A according to the present embodiment takes out the rotation corresponding to the rotation component of the planetary gear 3 as the rotation of the output shaft or the like integrated with the outer ring 62A of the bearing member 6A. Used for. That is, in the basic configuration, the relative rotation between the planetary gear 3 and the internal gear 2 is taken out as a rotation component of the planetary gear 3 from the inner ring 61 connected to the planetary gear 3 by a plurality of inner pins 4. Will be. On the other hand, in the present embodiment, the relative rotation between the planetary gear 3 and the internal gear 2 is taken out from the outer ring 62A integrated with the gear body 22 of the internal gear 2. In the present embodiment, as an example, in the gear device 1A, the inner ring 61A holding a plurality of inner pins 4 is fixed to a fixing member (hub member 104 or the like described later), and the outer ring 62A is fixed to the case 10 serving as a rotating member. It is used in the state of being used. That is, since the planetary gear 3 is connected to the fixing member by a plurality of internal pins 4 and the gear body 22 is fixed to the rotating member, the relative rotation between the planetary gear 3 and the internal gear 2 is internal. It is taken out from the tooth gear 2 (gear body 22). In other words, in the present embodiment, when the plurality of inner pins 4 rotate relative to the gear body 22, the rotational force of the gear body 22 is taken out as an output.

The gear device 1A from which the rotational force of the gear body 22 is taken out as an output in this way is used as an example in the wheel device W1 (see FIG. 17). In this case, since the rotating member (case 10) functions as the wheel body 102 (see FIG. 17), the wheel body 102 can be rotated along with the relative rotation between the internal gear 2 and the planetary gear 3. As described above, in the present embodiment, by using the gear device 1A for the wheel device W1, the wheel main body is on the traveling surface due to the rotational output when the plurality of inner pins 4 rotate relative to the gear main body 22. The wheel body 102 can be driven so as to roll the 102. In short, when the gear device 1A is used as the wheel device W1, the rotational force as an output is taken out from the rotating member as the wheel body 102 by applying the rotational force as an input to the eccentric shaft 7. That is, the gear device 1A operates with the rotation of the eccentric shaft 7 as the input rotation and the rotation of the rotating member to which the gear body 22 is fixed as the output rotation. As a result, in the gear device 1A, the output rotation decelerated at a relatively high reduction ratio with respect to the input rotation is obtained as the rotation of the wheel body 102.

As another second difference, the gear device 1A according to the present embodiment includes a plurality of planetary gears 3. Specifically, the gear device 1A includes two planetary gears 3 including a first planetary gear 301 and a second planetary gear 302. The two planetary gears 3 are arranged so as to face each other in a direction parallel to the rotation axis Ax1. That is, the planetary gear 3 includes the first planetary gear 301 and the second planetary gear 302 facing in the direction parallel to the rotation axis Ax1.

These two planetary gears 3 (first planetary gear 301 and second planetary gear 302) are arranged with a phase difference of 180 degrees around the rotation axis Ax1. In the example of FIG. 11, of the first planetary gear 301 and the second planetary gear 302, the center C1 of the first planetary gear 301 located on the input side (left side of FIG. 11) of the rotating shaft Ax1 is relative to the rotating shaft Ax1. It is in a state of being displaced (biased) toward the upper part of the figure. On the other hand, the center C2 of the second planetary gear 302 located on the output side (right side of FIG. 11) of the rotating shaft Ax1 is in a state of being displaced (biased) downward in the figure with respect to the rotating shaft Ax1. In this way, by arranging the plurality of planetary gears 3 evenly in the circumferential direction about the rotation axis Ax1, it is possible to balance the weight among the plurality of planetary gears 3. In the gear device 1A according to the present embodiment, since the weight is balanced among the plurality of planetary gears 3 in this way, the gap 75 (see FIG. 3) of the eccentric shaft 7 is omitted.

More specifically, the eccentric shaft 7 has two eccentric portions 72 with respect to one axial center portion 71. The centers (central axes) of these two eccentric portions 72 coincide with the centers C1 and C2 deviated from the rotation axis Ax1, respectively. Further, the shapes of the first planetary gear 301 and the second planetary gear 302 are the same. The opening 33 of the first planetary gear 301 accommodates the eccentric body bearing 5 mounted on the eccentric portion 72 centered on the center C1. The opening 33 of the second planetary gear 302 accommodates an eccentric body bearing 5 mounted on an eccentric portion 72 centered on the center C2. Here, the distance ΔL1 between the rotation axis Ax1 and the center C1 is the eccentricity of the first planetary gear 301 with respect to the rotation axis Ax1, and the distance ΔL2 between the rotation axis Ax1 and the center C2 is the second with respect to the rotation axis Ax1. 2 The amount of eccentricity of the planetary gear 302. In the present embodiment, the eccentricity amount ΔL1 and the eccentricity amount ΔL2 have opposite directions when viewed from the rotation axis Ax1, but their absolute values are the same. According to the above-described configuration, the shaft center portion 71 rotates (rotates) around the rotation shaft Ax1, so that the first planetary gear 301 and the second planetary gear 302 have a phase difference of 180 degrees around the rotation shaft Ax1. , Rotates (eccentric movement) around the rotation axis Ax1.

As another third difference, in the present embodiment, as shown in FIGS. 13 and 14, the eccentric body bearing 5 is composed of a roller bearing instead of the deep groove ball bearing as described in the basic configuration. That is, in the gear device 1A according to the present embodiment, the eccentric body bearing 5 uses a cylindrical (cylindrical) roller as the rolling element 53. Further, in the present embodiment, the eccentric inner ring 51 (see FIG. 3) and the eccentric outer ring 52 (see FIG. 3) are omitted. Therefore, the inner peripheral surface of the planetary gear 3 (opening 33) becomes the rolling surface of the plurality of rolling elements 53 instead of the eccentric outer ring 52, and the outer peripheral surface of the eccentric portion 72 becomes a plurality of rolling surfaces instead of the eccentric inner ring 51. It becomes the rolling surface of the rolling element 53. In the present embodiment, the eccentric body bearing 5 has a cage (retainer) 54, and the plurality of rolling elements 53 are each held by the cage 54 in a state in which the rolling elements 53 can rotate. The cage 54 holds the plurality of rolling elements 53 at equal pitches in the circumferential direction of the eccentric portion 72. Further, the cage 54 is not fixed to the planetary gear 3 and the eccentric shaft 7, and is rotatable relative to each of the planetary gear 3 and the eccentric shaft 7. As a result, as the cage 54 rotates, the plurality of rolling elements 53 held by the cage 54 move in the circumferential direction of the eccentric portion 72.

As another fourth difference, in the present embodiment, the case 10 is seamlessly integrated with the gear body 22 of the internal gear 2 and the outer ring 62A of the bearing member 6A. That is, in the basic configuration, the gear body 22 of the internal gear 2 is used in a state of being fixed to the case 10 together with the outer ring 62 of the bearing member 6. On the other hand, in the present embodiment, by devising the outer ring 62A, the outer ring 62A provided seamlessly and continuously in the direction parallel to the gear body 22 and the rotating shaft Ax1 is further a rotating member. It is provided seamlessly and continuously.

More specifically, the case 10 is cylindrical and constitutes the outer shell of the gear device 1A. In the present embodiment, since the case 10 which is a rotating member functions as, for example, a wheel body 102, the central axis of the cylindrical case 10 is configured to coincide with the rotating shaft Ax1. That is, in the case 10, at least the outer peripheral surface is a perfect circle centered on the rotation axis Ax1 (when viewed from one of the rotation axes Ax1 directions) in a plan view. As shown in FIG. 11, the case 10 has a body portion 18 and a cap 19. The body portion 18 is a cylindrical component in which both end faces in the rotation axis Ax1 direction are open. The cap 19 is a disk-shaped component that is attached to the end surface of the body portion 18 on the input side (left side of FIG. 11) of the rotation shaft Ax1 and closes the opening surface of the rotation shaft Ax1 on the body portion 18 on the input side. In the present embodiment, the gear body 22 of the internal gear 2 and the outer ring 62A of the bearing member 6A are seamlessly integrated with the body 18 of the case 10. As a result, the gear body 22 and the outer ring 62A are treated as one component (body portion 18). Therefore, the inner peripheral surface of the body portion 18 includes the inner peripheral surface 221 of the gear body 22 (see FIG. 14) and the inner peripheral surface 620 of the outer ring 62A (see FIG. 13).

In addition to the above points, for example, the number of teeth of the internal gear 2 and the planetary gear 3, the reduction ratio, the number of loose fitting holes 32 and the internal pin 4, and the specific shape and dimensions of each part are also determined. The present embodiment and the basic configuration are appropriately different. For example, the free fitting holes 32 and the inner pins 4 are provided by 18 each in the basic configuration, whereas in the present embodiment, 12 are provided as an example.

<Ingenuity for inner ring>
Next, the device for the inner ring 61A of the bearing member 6A in the gear device 1A according to the present embodiment will be described in detail with reference to FIGS. 11 to 16.

In the present embodiment, as described above, the inner ring 61A of the bearing member 6A is configured to include two parts, the first inner ring 601 and the second inner ring 602, which face each other in the direction parallel to the rotation shaft Ax1. The first inner ring 601 and the second inner ring 602 are combined in a state where the facing surfaces 601A and 602A are in contact with each other. In other words, the inner ring 61A is divided into two parts, a first inner ring 601 and a second inner ring 602, which are arranged in a direction parallel to the rotation axis Ax1.

The first inner ring 601 and the second inner ring 602 are both annular parts. Both the first inner ring 601 and the second inner ring 602 have an annular shape that is a perfect circle in a plan view. The outer diameter φ1 (see FIG. 15) is the same in the first inner ring 601 and the second inner ring 602, and the inner diameter is also substantially the same. As an example in this embodiment, the dimension in the direction parallel to the rotation axis Ax1 is larger in the second inner ring 602 than in the first inner ring 601 but is not limited to this dimensional relationship.

Both the first inner ring 601 and the second inner ring 602 are one size smaller than the outer ring 62A and are arranged inside the outer ring 62A. Here, since the inner diameter φ3 (see FIG. 15) of the outer ring 62A is larger than the outer diameter φ1 of the first inner ring 601 and the second inner ring 602, the inner peripheral surface 620 of the outer ring 62A and the first inner ring 601 and the second inner ring 602 A gap is created between the outer peripheral surface and the outer peripheral surface. Further, as will be described in detail later, the outer diameter φ1 of the first inner ring 601 and the second inner ring 602 is a virtual circle VC1 passing through the bottoms of a plurality of pin holding grooves 223 (see FIG. 14) on the inner peripheral surface 221 of the gear body 22. It is even smaller than the diameter φ2 (see FIG. 15) of (see FIG. 14).

Here, the first inner ring 601 and the second inner ring 602 are arranged so that the first inner ring 601 is on the planetary gear 3 side and the second inner ring 602 is on the opposite side of the planetary gear 3 in the direction parallel to the rotation axis Ax1. Has been done. In other words, in the first inner ring 601 and the second inner ring 602, the first inner ring 601 is on the input side of the rotating shaft Ax1 (left side in FIG. 11), and the second inner ring 602 is on the output side of the rotating shaft Ax1 (right side in FIG. 11). It is arranged so as to be. Therefore, the surface 601A of the first inner ring 601 facing the second inner ring 602 is formed of a surface of the first inner ring 601 facing the output side (right side of FIG. 11) of the rotation shaft Ax1. On the contrary, the facing surface 602A of the second inner ring 602 with the first inner ring 601 is formed of a surface of the second inner ring 602 facing the input side (left side of FIG. 11) of the rotation shaft Ax1. The first inner ring 601 and the second inner ring 602 are combined with each other so as to bring the facing surfaces 601A and 602A into contact with each other to form the inner ring 61A.

As shown in FIG. 12, the first inner ring 601 and the second inner ring 602 are connected by a plurality of positioning pins 65 and a plurality of bolts 66 in a state of being combined as described above. The plurality of positioning pins 65 are press-fitted into a plurality of holes penetrating the inner ring 61A from the first inner ring 601 to the second inner ring 602 in a direction parallel to the rotation axis Ax1. Further, the plurality of bolts 66 are fastened to the first inner ring 601 through the second inner ring 602. Therefore, the first inner ring 601 and the second inner ring 602 are connected by a plurality of bolts 66 in a state where the relative positions in the plane orthogonal to the rotation axis Ax1 are positioned by the plurality of positioning pins 65. ..

Here, in the bearing member 6A, the plurality of rolling elements 63 are located on the dividing surface of the first inner ring 601 and the second inner ring 602 in the inner ring 61A, as shown in FIG. In the present embodiment, since the facing surface 601A of the first inner ring 601 to the second inner ring 602 becomes a dividing surface between the first inner ring 601 and the second inner ring 602, the facing surface of the first inner ring 601 to the second inner ring 602. A plurality of rolling elements 63 are located on a plane including 601A. In the present embodiment, the bearing member 6A is a cross roller bearing that receives a load in the radial direction, a load in the thrust direction (direction along the rotating shaft Ax1), and a bending force (bending moment load) with respect to the rotating shaft Ax1. Therefore, each of the plurality of rolling elements 63 of the bearing member 6 is composed of a cylindrical roller having an inclination of 45 degrees with respect to a plane orthogonal to the rotation axis Ax1. Such a plurality of rolling elements 63 are located on the same plane as the facing surface 601A of the first inner ring 601 with the second inner ring 602.

In this embodiment, in particular, the center of each of the plurality of rolling elements 63 in the direction parallel to the rotation axis Ax1 is located on the same plane as the facing surface 601A of the first inner ring 601 with the second inner ring 602. In other words, the inner ring 61A is divided into the first inner ring 601 and the second inner ring 602 with the plane including the centers of the plurality of rolling elements 63 in the direction parallel to the rotation axis Ax1 as the dividing surface. With such a configuration, when assembling the bearing member 6A, a plurality of rolling elements 63 set with respect to the outer ring 62A are sandwiched between the first inner ring 601 and the second inner ring 602 from both sides in the direction parallel to the rotation shaft Ax1. By doing so, the bearing member 6A can be assembled relatively easily.

In the present embodiment, the oil seal 15 closes the gap between the second inner ring 602 and the eccentric shaft 7 (axis center portion 71). Similarly, the oil seal 16 closes the gap between the second inner ring 602 and the outer ring 62. The space sealed by the plurality of oil seals 14, 15 and 16 constitutes the lubricant holding space 17 (see FIG. 11) as in the basic configuration.

As described above, since the inner ring 61A is divided into two parts, the first inner ring 601 and the second inner ring 602, there is a slight gap between the first inner ring 601 and the second inner ring 602. Can occur. By creating such a gap, for example, the lubricant easily circulates in the lubricant holding space 17 through the gap. In particular, if the gap between the first inner ring 601 and the second inner ring 602 is small, the lubricant in the lubricant holding space 17 is expected to spread through the gap due to, for example, a capillary phenomenon. Therefore, as compared with the case where the inner ring 61A is not divided into two parts, the first inner ring 601 and the second inner ring 602, for example, even in the long-term use of the gear device 1A, the lubricant is used as the lubricant holding space 17 It becomes easy to spread to the whole of the gear device 1A, and problems such as a decrease in transmission efficiency in the gear device 1A are less likely to occur.

Further, since the inner ring 61A is divided into two parts, the first inner ring 601 and the second inner ring 602, it is possible to facilitate the assembly of the bearing member 6A without significantly complicating the processing of the inner ring 61A. can. Since the processing of the inner ring 61A is not complicated, the size of the inner ring 61 can be suppressed to a relatively small size, and a bearing member 6A that is relatively compact as a cross roller bearing can be realized.

By the way, in the present embodiment, as in the basic configuration, a plurality of inner pins 4 connect the planetary gear 3 and the inner ring 61A of the bearing member 6A. Specifically, one end of the inner pin 4 in the longitudinal direction (the end on the input side of the rotating shaft Ax1) is inserted into the free fitting hole 32 of the planetary gear 3 (first planetary gear 301 and second planetary gear 302). The other end of the inner pin 4 in the longitudinal direction (the end on the output side of the rotating shaft Ax1) is inserted into the holding hole 611 of the inner ring 61A.

Since the diameter of the inner pin 4 is slightly larger than that of the holding hole 611, the inner pin 4 is prohibited from revolving in the holding hole 611 when it is inserted into the holding hole 611 of the bearing member 6A. , Rotation within the holding hole 611 is possible. That is, the inner pin 4 is not press-fitted into the holding hole 611 even when it is inserted into the holding hole 611, so that the inner pin 4 can rotate in the holding hole 611. As described above, in the gear device 1A according to the present embodiment, each of the plurality of inner pins 4 is held by the inner ring 61A in a state in which it can rotate, so that when the inner pins 4 revolve in the free fitting hole 32, , The inner pin 4 itself can rotate.

Here, in the present embodiment, unlike the basic configuration, each of the plurality of holding holes 611 is configured to penetrate only the first inner ring 601 of the inner rings 61A, instead of penetrating the entire inner ring 61A. Has been done. That is, the first inner ring 601 has a plurality of holding holes 611 through which the plurality of inner pins 4 penetrate in the direction parallel to the rotation axis Ax1. The inner pin 4 is held by the inner ring 61A by inserting the other end in the longitudinal direction (the end on the output side of the rotation shaft Ax1) into the holding hole 611.

In the present embodiment, since the inner pin 4 is not inserted into the second inner ring 602, the holding hole 611 is not provided in the second inner ring 602. Therefore, each end surface of the plurality of inner pins 4 is abutted against the facing surface 602A of the second inner ring 602 with the first inner ring 601. That is, the end surface of the inner pin 4 on the side opposite to the planetary gear 3 (output side of the rotating shaft Ax1) in the longitudinal direction is abutted against the surface of the second inner ring 602 (opposing surface 602A). The end face in the longitudinal direction of the inner pin 4 may be lightly in contact with or separated from the facing surface 602A of the second inner ring 602 to the extent that the rotation of the inner pin 4 is not hindered. Therefore, the movement of the inner pin 4 to the output side of the rotation shaft Ax1 is restricted by the second inner ring 602, and the lubricant in the lubricant holding space 17 is suppressed from leaking through the holding hole 611.

Further, since the diameter of the inner pin 4 is slightly larger than the holding hole 611, between the inner peripheral surface of each of the plurality of holding holes 611 in the first inner ring 601 and the outer peripheral surface of each of the plurality of inner pins 4. A gap is formed in. That is, the holding hole 611 is a hole into which the inner pin 4 is loosely fitted, and the inner pin 4 is a holding hole in a state where a spatial margin (gap) is secured between the holding hole 611 and the inner peripheral surface of the holding hole 611. It is inserted in 611. However, since the inner pin 4 may rotate in the holding hole 611, the inner peripheral surface and the inner side of the holding hole 611 are compared with the gap between the inner peripheral surface 321 of the free fitting hole 32 and the inner pin 4. The gap between the pin 4 and the pin 4 is small. Further, it is not essential to secure a gap as a cavity between the inner peripheral surface of the holding hole 611 and the inner pin 4, and for example, the gap may be filled with a fluid such as a liquid. Specifically, the gap between the inner peripheral surface of the holding hole 611 and the inner pin 4 is filled with a lubricant. Therefore, the rotation of the inner pin 4 in the holding hole 611 is smoothed by the lubricant.

Further, the gear device 1A according to the present embodiment further includes a lubricant circulation path RL1 as shown in FIG. In FIG. 16, the flow of the lubricant through the circulation path RL1 is schematically represented by a broken line arrow. The circulation path RL1 is a path for circulating the lubricant through at least a gap between the first inner ring 601 and the second inner ring 602, a space for accommodating each of the plurality of rolling elements 63, and each of the plurality of holding holes 611 (the circulation path RL1). Circulation route). That is, the circulation path RL1 includes a gap between the first inner ring 601 and the second inner ring 602, a space for accommodating the rolling element 63, and a holding hole 611, and is formed in a loop shape as shown in FIG. There is. As a result, for example, the lubricant injected into the space accommodating the rolling element 63 is provided along the circulation path RL1 with a gap between the first inner ring 601 and the second inner ring 602, and the holding hole 611 (with the inner peripheral surface). It becomes easy to circulate again to the space for accommodating the rolling element 63 through the gap between the inner pin 4 and the inner pin 4. However, the direction in which the lubricant moves through the circulation path RL1 is not limited to the direction indicated by the arrow in FIG. 16, and may be in the opposite direction.

Further, the gear device 1A according to the present embodiment satisfies the following conditions for the surface hardness of each component.

That is, each of the plurality of inner pins 4 and the first inner ring 601 have the same surface hardness. Specifically, the difference between the surface hardness of each of the plurality of inner pins 4 and the surface hardness of the first inner ring 601 is HRC3 or less. That is, the surface hardness of the inner pin 4 is set in the range of ± 3 in Rockwell hardness (HRC) with respect to the surface hardness of the first inner ring 601. Here, the difference between the surface hardness of the inner pin 4 and the surface hardness of the first inner ring 601 is preferably HRC2 or less, and more preferably HRC1 or less. The "surface hardness of the first inner ring 601" as used herein refers to the hardness of the inner peripheral surface of the holding hole 611 in at least the first inner ring 601. Since the first inner ring 601 holds the inner pin 4 in a state where it can rotate in the holding hole 611, the surface hardness of the inner pin 4 and the first inner ring 601 is about the same as in the present embodiment (HRC3 or less). By setting the difference), the effect of suppressing the wear of the inner pin 4 and the first inner ring 601 is expected. As a result, wear debris and the like are less likely to be generated by the rotation of the inner pin 4 in the holding hole 611, and it is easy to maintain the smooth rotation of the inner pin 4 for a long period of time.

Further, the surface hardness of each of the plurality of inner pins 4 is about HRC60. More precisely, the surface hardness of each of the plurality of inner pins 4 is within the range of HRC60 ± 3. In the present embodiment, the surface hardness of the inner pin 4 and the first inner ring 601 is about the same (difference of HRC3 or less), so that the surface hardness of the first inner ring 601 is within the range of HRC60 ± 6. Here, the surface hardness of the inner pin 4 is preferably in the range of HRC60 ± 2, and more preferably in the range of HRC60 ± 1. As a result, wear debris and the like are less likely to be generated by the rotation of the inner pin 4 in the holding hole 611, and it is easy to maintain the smooth rotation of the inner pin 4 for a long period of time.

Further, in the present embodiment, the surface hardness of the second inner ring 602 is about the same as that of the first inner ring 601 (and the inner pin 4). Specifically, the difference between the surface hardness of the second inner ring 602 and the surface hardness of the first inner ring 601 is HRC3 or less. As a means for increasing (hardening) the hardness of a metal part, for example, alloying or heat treatment is used.

<Ingenuity for the outer ring>
Next, the device for the outer ring 62A of the bearing member 6A in the gear device 1A according to the present embodiment will be described in detail with reference to FIGS. 11 to 16.

In the present embodiment, as described above, the outer ring 62A of the bearing member 6A is seamlessly and continuously provided in the direction parallel to the gear body 22 and the rotation shaft Ax1 (tooth muscle direction of the internal teeth 21). The term "seamless" as used in the present disclosure means a structure in which a plurality of parts (parts) are seamlessly connected, and means a state in which the plurality of parts (parts) cannot be separated without breaking. That is, in the present embodiment, the outer ring 62A and the gear body 22 prepared as separate parts are not connected by, for example, fasteners (bolts or the like) or an adhesive, but the outer ring 62A and the gear body 22 are connected. Are integrated so that they are seamless and continuous.

Specifically, for example, by forming the outer ring 62A and the gear body 22 integrally by processing such as cutting on one base material made of a metal block, the outer ring 62A and the gear body 22 that are seamlessly continuous are realized. Be made. Alternatively, in the case of casting or the like, the outer ring 62A and the gear body 22 are integrally formed by pouring one base material made of molten metal into a molding mold, and the outer ring 62A and the gear body 22 are seamlessly continuous. Is embodied. As described above, in the gear device 1A according to the present embodiment, the outer ring 62A and the gear main body 22 are integrally formed by, for example, processing one base material, so that the gear main body 22 and the rotary shaft Ax1 are parallel to each other. The outer ring 62A is seamlessly and continuously provided in the direction. In other words, the method for manufacturing the gear device 1A includes a step of integrally forming the outer ring 62A and the gear body 22 by processing one substrate.

As described above, in the gear device 1A according to the present embodiment, the outer ring 62A is seamlessly and continuously provided in the direction parallel to the gear body 22 and the rotating shaft Ax1, so that the internal gear 2 and the bearing member 6A are provided. It becomes easier to improve the accuracy of centering. That is, the center of the gear body 22 of the internal gear 2 and the center of the outer ring 62A of the bearing member 6A can be easily maintained on the rotating shaft Ax1 with high accuracy. As a result, the gear device 1A has an advantage that problems such as vibration caused by poor centering and a decrease in transmission efficiency are unlikely to occur.

Both the gear body 22 and the outer ring 62A have an annular shape that is a perfect circle in a plan view. In this embodiment, in particular, the gear body 22 and the outer ring 62A are seamlessly integrated with the body 18 of the case 10. In other words, a part of the body 18 of the case 10 functions as the gear body 22 and the outer ring 62A. Therefore, as shown in FIG. 15, the outer diameters of the gear body 22 and the outer ring 62A are the same. On the other hand, the inner diameter differs between the gear body 22 and the outer ring 62A.

Specifically, as shown in FIG. 14, a plurality of grooves are formed on the inner peripheral surface 221 of the gear body 22 over the entire circumferential direction. Each of these plurality of grooves is a plurality of pin holding grooves 223 as a holding structure for the plurality of outer pins 23. In other words, the holding structure of the plurality of outer pins 23 includes a plurality of pin holding grooves 223 formed on the inner peripheral surface 221 of the gear body 22. The plurality of pin holding grooves 223 are all of the same shape and are provided at equal pitches. The plurality of pin holding grooves 223 are all parallel to the rotation shaft Ax1 and are formed over the entire width of the gear body 22. However, in the present embodiment, since the gear body 22 is a part of the body portion 18 as described above, the plurality of pin holding grooves 223 are portions of the body portion 18 corresponding to the gear body 22 (see FIG. 11). It is formed only in. The plurality of outer pins 23 are combined with the gear body 22 (body portion 18) so as to fit into the plurality of pin holding grooves 223. Each of the plurality of outer pins 23 is held in a state in which it can rotate in the pin holding groove 223, and the pin holding groove 223 restricts the movement of the gear body 22 in the circumferential direction.

By forming such a plurality of pin holding grooves 223, the inner diameter of the gear body 22 is maximum at the bottom of the pin holding groove 223 and minimum except for the pin holding groove 223. In the present embodiment, the diameter φ2 of the virtual circle VC1 passing through the bottoms of the plurality of pin holding grooves 223, that is, the maximum value of the inner diameter of the gear body 22, is defined as the inner diameter of the gear body 22. As shown in FIG. 15, the inner diameter (φ2) of the gear body 22 is different from the inner diameter φ3 of the outer ring 62A of the bearing member 6A. In short, the inner diameter φ3 of the outer ring 62A is different from the diameter φ2 of the virtual circle VC1 passing through the bottoms of the plurality of pin holding grooves 223 in which the plurality of outer pins 23 on the inner peripheral surface 221 of the gear body 22 are held. This makes it easy to clearly separate the functions of the gear body 22 and the outer ring 62A due to the difference in the inner diameters of the gear body 22 and the outer ring 62A while the gear body 22 and the outer ring 62A are seamlessly connected.

Further, in the present embodiment, as shown in FIG. 15, the inner diameter φ3 of the outer ring 62A is larger than the diameter φ2 of the virtual circle VC1 (φ3> φ2). That is, the diameter φ2 of the virtual circle VC1, which is (the maximum value of) the inner diameter of the gear body 22, is smaller than the inner diameter φ3 of the outer ring 62A. As a result, on the inner peripheral surface of the body portion 18, the height D1 is set between the bottom portions of the plurality of pin holding grooves 223 on the inner peripheral surface 221 of the gear body 22 and the outer ring 62A, as shown in FIG. There will be a step. The height D1 of the step shall be, for example, 1/12 (φ10 × 1/12) or more (φ10 × 1/12) or more and 2/10 times (φ10 × 0.2) or less of the diameter φ10 (see FIG. 14) of the outer pin 23. Is preferable. As an example, when the diameter φ10 of the outer pin 23 is about 2.5 mm, the height D1 of the step is preferably 0.2 mm or more and 0.5 mm or less. Due to this step, it is possible to avoid interference between the outer pin 23 held by the pin holding groove 223 and the inner peripheral surface 620 of the outer ring 62A.

Further, in the present embodiment, the outer diameter φ1 of the inner ring 61A (first inner ring 601 and second inner ring 602) is smaller than the diameter φ2 of the virtual circle VC1. That is, the diameter φ2 of the virtual circle VC1 is larger than the outer diameter φ1 of the inner ring 61A, and the inner diameter φ3 of the outer ring 62A is larger than the diameter φ2 of the virtual circle VC1. In other words, the diameter φ2 of the virtual circle VC1 is a value between the outer diameter φ1 of the inner ring 61A and the inner diameter φ3 of the outer ring 62A (φ1 <φ2 <φ3).

Further, as shown in FIG. 16, a holding recess 67 is arranged between the inner peripheral surface 620 of the outer ring 62A and the inner peripheral surface 221 of the gear body 22. The holding recess 67 is formed of a groove provided over the entire circumference of the outer ring 62A in the circumferential direction. The holding recess 67 is formed in a size and shape that can hold the lubricant by, for example, surface tension. That is, the holding recess 67 functions as an "oil reservoir" for storing the lubricant (lubricating oil). In the present embodiment, the gear body 22 and the outer ring 62A are arranged so that the gear body 22 is on the input side of the rotating shaft Ax1 (left side in FIG. 16) and the outer ring 62A is on the output side of the rotating shaft Ax1 (right side in FIG. 16). Has been done. Therefore, the inner peripheral surface 221 of the gear body 22, the holding recess 67, and the inner peripheral surface 620 of the outer ring 62A are the inner peripheral surfaces of the gear main body 22, the holding recess 67, and the inner circumference of the outer ring 62A from the input side of the rotating shaft Ax1. Line up in the order of faces 620.

In the present embodiment, as an example, as shown in FIG. 16, the holding recess 67 has a rectangular cross-sectional shape orthogonal to the circumferential direction of the outer ring 62A. The depth D2 of the holding recess 67 (from the inner peripheral surface 620 of the outer ring 62A) and the width D3 of the holding recess 67 are both larger than the height D1 of the step. It is preferable that the depth D2 and the width D3 of the holding recess 67 are 1/10 (φ10 × 1/10) or more (φ10 × 1/10) or more and twice (φ10 × 2) or less of the diameter φ10 of the outer pin 23, respectively. As an example, when the diameter φ10 of the outer pin 23 is about 2.5 mm, the depth D2 and the width D3 of the holding recess 67 are preferably 0.25 mm or more and 5.0 mm or less. In the example of FIG. 16, the depth D2 of the holding recess 67 is larger than the width D3 of the holding recess 67, but the present invention is not limited to this example, and the depth D2 of the holding recess 67 may be equal to or less than the width D3. Further, the cross-sectional shape of the holding recess 67 is not limited to a rectangular shape, but may be a semicircular shape, a triangular shape, or another polygonal shape.

Here, the gear device 1A according to the present embodiment is a lubricant that is connected from the holding recess 67 to each of the plurality of inner pins 4, each of the plurality of outer pins 23, and at least one of the plurality of rolling elements 63. Further routes are provided. That is, the holding recess 67 as an "oil pool" is connected to each of the plurality of inner pins 4, each of the plurality of outer pins 23, and at least one of the plurality of rolling elements 63 by a lubricant path. ing. As a result, the lubricant held in the holding recess 67 is supplied to each of the plurality of inner pins 4, each of the plurality of outer pins 23, and at least one of the plurality of rolling elements 63, and the inner pin 4 is supplied. , Smooth at least one movement of the outer pin 23 and the rolling element 63. In the present embodiment, by locating the holding recess 67 on the circulation path RL1 of the lubricant, a part of the circulation path RL1 is used as a “lubricant” path, and the lubricant in the holding recess 67 is used as the inner pin 4. , Supply to at least one of the outer pin 23 and the rolling element 63. In particular, in the present embodiment, as shown in FIG. 16, since the inner pin 4, the outer pin 23, and the rolling element 63 are all located on the circulation path RL1, the lubricant held in the holding recess 67 is used. It can be supplied to all of the inner pin 4, the outer pin 23, and the rolling element 63.

In particular, in the present embodiment, the rolling element 63 is located on the circulation path RL1. Therefore, when the bearing member 6A operates and the rolling element 63 rotates, the rolling element 63 functions as a pump, and the lubricant in the lubricant holding space 17 is positively circulated via the circulation path RL1. Is possible. In particular, since the dividing surface of the first inner ring 601 and the second inner ring 602 is at a position facing (opposing) the rolling element 63, the rolling element 63 efficiently acts as a pump when the rolling element 63 rotates. .. As a result, the lubricant in the lubricant holding space 17 is easily circulated, and even during long-term use of the gear device 1A, the lubricant is easily distributed throughout the lubricant holding space 17, and is transmitted in the gear device 1A. Problems such as reduced efficiency are less likely to occur.

<Application example>
As shown in FIG. 17, the gear device 1A according to the present embodiment constitutes the wheel device W1 together with the wheel body 102. In other words, the wheel device W1 according to the present embodiment includes a gear device 1A and a wheel body 102. The wheel body 102 rolls on the traveling surface due to the rotational output when the plurality of inner pins 4 rotate relative to the gear body 22. In the present embodiment, among the cases 10 constituting the outer shell of the gear device 1, the body portion 18 and the cap 19 as "rotating members" constitute the wheel body 102. That is, in the wheel device W1 according to the present embodiment, the gear device 1A uses the rotation of the eccentric shaft 7 as the input rotation and the rotation of the rotating member (body portion 18, etc.) to which the gear body 22 is fixed as the output rotation. By operating, the wheel body 102 rotates and rolls on the traveling surface. Here, for example, a rubber tire 103 is mounted on the contact surface of the wheel body 102 with the traveling surface, that is, the outer peripheral surface of the body portion 18 serving as a ground contact surface.

The wheel device W1 configured in this way is used in a state where the inner ring 61A is fixed to the hub member 104 which is a fixing member. As a result, the rotation of the eccentric shaft 7 causes the wheel body 102 to rotate due to the relative rotation of the rotating member (wheel body 102) with respect to the fixing member (hub member 104). In the present embodiment, as an example, in the wheel device W1, the inner ring 61A (first inner ring 601 and second inner ring 602) is fixed to the hub member 104 by using a plurality of bolts 66. At this time, it is preferable that the second inner ring 602 of the inner ring 61A is fixed to the hub member 104 or the like.

Here, when the gear device 1A is used for the wheel device W1, basically, the gear device 1A is used with the rotation shaft Ax1 in a posture along the horizontal plane. Therefore, the lubricant circulating through the circulation path RL1 (see FIG. 16) is likely to be supplied to the vicinity of the eccentric shaft 7 such as the eccentric body bearing 5 (rolling body 53) and the second bearing 92. That is, a part of the lubricant circulating through the circulation path RL1 passes through the gap between the planetary gear 3 (second planetary gear 302) and the first inner ring 601 due to gravity, and the eccentric body bearing 5, the second bearing 92, etc. It becomes easy to be supplied to. As a result, even if the lubricant is blown to the outer peripheral side by centrifugal force during high-speed rotation of the eccentric shaft 7, the lubricant can be supplied to the periphery of the eccentric shaft 7 through the circulation path RL1 and the eccentric shaft 7 rotates smoothly. Will be easier to maintain.

The wheel device W1 using the gear device 1A is applied to a vehicle such as an automated guided vehicle (AGV), for example. That is, the wheel device W1 is attached to the hub member 104 provided on the vehicle body of the vehicle, and the wheel body 102 rotates and rolls on the traveling surface, so that the vehicle travels on a flat traveling surface made of a floor surface or the like. do. As an example, a plurality of (for example, four) gear devices 1A are mounted on the vehicle body, and the eccentric shafts 7 of each gear device 1A are driven by individual drive sources, thereby laying out an "in-wheel motor". Is adopted. As a result, the drive source swings the planetary gear 3 by rotating the eccentric shaft 7 of the wheel device W1 about the rotation shaft Ax1. As a result, the rotation (input rotation) generated by the drive source is decelerated in the gear device 1A at a relatively high reduction ratio, and the wheel body 102 is rotated with a relatively high torque.

By the way, in the present embodiment, the outer peripheral surface 680 of the outer ring 62A constitutes a pressure receiving surface that receives a larger stress than the outer peripheral surface 224 of the gear body 22. In other words, a larger stress acts on the outer peripheral surface 680 (pressure receiving surface) of the outer ring 62A from the outside as compared with the outer peripheral surface 224 of the gear body 22. In particular, when the gear device 1A is used for the wheel device W1 or the like, it is preferable that the outer ring 62A is configured so that a larger stress acts on the outer peripheral surface 680 as compared with the outer peripheral surface 224 of the gear body 22. The gear body 22 has a relatively large gap between the gear body 22 and the planetary gear 3 so that the planetary gear 3 can revolve (swing) inside the gear body 22. On the other hand, the outer ring 62A may have a relatively small gap between the outer ring 62A and the inner ring 61A as long as the inner ring 61A can rotate on the inside. That is, since the outer ring 62A has a structure closer to a solid structure in which the inside is clogged as compared with the gear body 22, it has high rigidity against an external force acting in the radial direction. Therefore, by using the outer peripheral surface 680 of the outer ring 62A as the pressure receiving surface, stress from the outside can be received on the outer ring 62A side having high rigidity, and the resistance to the stress of the gear device 1A as a whole becomes high.

More specifically, stress from the exterior body fitted to the outer periphery of the outer ring 62A acts on the pressure receiving surface (outer peripheral surface 680 of the outer ring 62A). Here, the tire 103 is an example of an exterior body fitted to the outer periphery of the outer ring 62A. That is, when the tire 103 is mounted so as to fit on the outer periphery of the body portion 18, the stress (fitting pressure) acting on the body portion 18 from the tire 103 is larger in the outer ring 62A than in the gear body 22. .. Specifically, for example, as shown in FIG. 17, by providing the spacer 68 at the portion corresponding to the outer ring 62A on the outer peripheral surface of the body portion 18, the outer diameter of the body portion 18 is made larger than that of the gear body 22. Increase with the outer ring 62A. As a result, when the tire 103 as an exterior body is mounted on the body portion 18, the stress from the tire 103 becomes larger on the outer ring 62A side than on the gear body 22 side. However, the configuration is not limited to the configuration in which the spacer 68 is provided, and for example, the outer diameter of the gear body 22 may be reduced, or the inner diameter of the exterior body (tire 103, etc.) may be made smaller on the outer ring 62A side than on the gear body 22 side. However, the same effect can be achieved.

Alternatively, in the gear device 1A, even when the stress from the exterior body is the same on the outer peripheral surface 680 of the outer ring 62A and the outer peripheral surface 224 of the gear body 22, the reaction force from the ground such as the traveling surface is generated. It may be configured to be larger on the outer peripheral surface 680 side of the outer ring 62A as the pressure receiving surface. Specifically, for example, when the gear device 1A is used as the wheel device W1, the reaction force from the ground such as the running surface becomes larger on the outer ring 62A side than on the gear body 22 side by adjusting the camber angle. It is composed of. In this case, the ground contact pressure from the ground contact surface acts on the pressure receiving surface (the outer peripheral surface 680 of the outer ring 62A).

Further, the gear device 1A according to the present embodiment is not limited to the wheel device W1, and can be applied to, for example, a robot such as a horizontal articulated robot (SCARA type robot) as described in the basic configuration.

<Modification example>
Embodiment 1 is just one of the various embodiments of the present disclosure. The first embodiment can be changed in various ways depending on the design and the like as long as the object of the present disclosure can be achieved. In addition, the drawings referred to in the present disclosure are all schematic views, and the ratio of the size and the thickness of each component in the drawing does not necessarily reflect the actual dimensional ratio. .. Hereinafter, modified examples of the first embodiment are listed. The modifications described below can be applied in combination as appropriate.

The inner pin 4 only needs to penetrate the first inner ring 601 of the first inner ring 601 and the second inner ring 602 constituting the inner ring 61A, and as shown in FIGS. 18A and 18B, the inner ring 602 of the second inner ring 602. The inner pin 4 may be partially or completely inserted. In the example of FIG. 18A, the holding hole 611 extends to a part of the second inner ring 602 in the direction parallel to the rotation axis Ax1, and the end of the inner pin 4 penetrating the first inner ring 601 is the second inner ring. It is inserted halfway through 602. In the example of FIG. 18B, the holding hole 611 is formed so as to penetrate both the first inner ring 601 and the second inner ring 602 in a direction parallel to the rotation axis Ax1, and the inner pin 4 penetrating the first inner ring 601. Also penetrates the second inner ring 602.

In the first embodiment, the gear device 1A having two types of planetary gears 3 is exemplified, but the gear device 1A may include three or more planetary gears 3. For example, when the gear device 1A includes three planetary gears 3, it is preferable that these three planetary gears 3 are arranged with a phase difference of 120 degrees around the rotation axis Ax1. Further, the gear device 1A may include only one planetary gear 3.

Further, it is not an essential configuration in the gear device 1A that at least a part of each of the plurality of inner pins 4 is arranged at the same position as the bearing member 6A in the axial direction of the bearing member 6A. That is, the gear device 1A may include a bearing member 6A, an internal gear 2, a planetary gear 3, and a plurality of internal pins 4. The bearing member 6A has an outer ring 62A and an inner ring 61A arranged inside the outer ring 62A. The inner ring 61A is rotatably supported relative to the outer ring 62A. The gear body 22 of the internal gear 2 is fixed to the outer ring 62A. Each of the plurality of inner pins 4 is held by the inner ring 61A in a state in which it can rotate. Here, each of the plurality of inner pins 4 may be arranged so as to be aligned with (opposite) the bearing member 6A in the axial direction of the bearing member 6A.

Further, the number of inner pins 4 and the number of outer pins 23 (the number of internal teeth 21) and the number of external teeth 31 described in the first embodiment are merely examples and can be appropriately changed.

Further, the bearing member 6A is not limited to the cross roller bearing, but may be a deep groove ball bearing, an angular contact ball bearing, or the like. However, the bearing member 6A has a load in the radial direction, a load in the thrust direction (direction along the rotating shaft Ax1), and a bending force (bending moment load) with respect to the rotating shaft Ax1, such as a four-point contact ball bearing. It is preferable to be able to withstand any of these.

Further, the eccentric body bearing 5 is not limited to the roller bearing, and may be, for example, a deep groove ball bearing, an angular contact ball bearing, or the like.

Further, the material of each component of the gear device 1A is not limited to metal, and may be, for example, a resin such as engineering plastic.

Further, the gear device 1A only needs to be able to take out the relative rotation between the inner ring 61A and the outer ring 62A of the bearing member 6A as an output, and is not limited to the configuration in which the rotational force of the outer ring 62A is taken out as an output. For example, the rotational force of the inner ring 61A that rotates relative to the outer ring 62A may be taken out as an output.

Further, the lubricant is not limited to a liquid substance such as lubricating oil (oil), but may be a gel-like substance such as grease.

Further, the gear device 1A may include an inner roller. That is, in the gear device 1A, it is not essential that each of the plurality of inner pins 4 comes into direct contact with the inner peripheral surface 321 of the clearance fitting hole 32, and each of the plurality of inner pins 4 and the clearance fitting hole 32 An inner roller may intervene between the two. In this case, the inner roller is mounted on the inner pin 4 and can rotate around the inner pin 4.

Further, each of the plurality of inner pins 4 may be held by the inner ring 61A in a state in which it can rotate, and each of the plurality of inner pins 4 is directly held by the inner ring 61A in the gear device 1A. Not required. For example, each of the plurality of inner pins 4 may be indirectly held by the inner ring 61A by being inserted into a holding hole formed in an output shaft or a carrier integrated with the inner ring 61A.

Further, it is not essential in the gear device 1A that the support 8 positions the plurality of inner pins 4 with respect to the support 8 in both the circumferential direction and the radial direction. For example, the support 8 has a slit-shaped support hole 82 extending in the radial direction, and the plurality of inner pins 4 may be positioned with respect to the support 8 only in the circumferential direction. On the contrary, the support 8 may position the plurality of inner pins 4 with respect to the support 8 only in the radial direction.

Further, the gear device 1A may adopt at least one of the device for the inner ring 61A of the bearing member 6A and the device for the outer ring 62A, and it is not essential to adopt both of them. That is, in the gear device 1A, the inner ring 61A has the first inner ring 601 and the second inner ring 602 (a device for the inner ring 61A), and the outer ring 62A is seamlessly and continuously provided with the gear body 22 (about the outer ring 62A). (Ingenuity) and only one of them may be adopted.

Further, since the gear device 1A may adopt at least one of the device for the inner ring 61A and the device for the outer ring 62A, other configurations can be appropriately omitted or changed from the basic configuration. For example, in the gear device 1A, the inner pin 4 may be held in a state of being press-fitted to the inner ring 61A (or a carrier integrated with the inner ring 61A), as in the first related technique. Each of the plurality of inner pins 4 is held in a state where it cannot rotate with respect to the inner ring 61A. Further, each of the plurality of inner pins 4 does not have to be arranged at the same position as the bearing member 6A in the axial direction of the bearing member 6A. Alternatively, in the gear device 1A, as in the second related technique, the plurality of inner pins 4 may be held only by the inner ring 61A (or the carrier integrated with the inner ring 61A). In this case, the support 8 can be omitted. Further, even when the support 8 that supports (bundles) the plurality of inner pins 4 is provided, it is not essential that the support 8 is positioned by bringing the outer peripheral surface 81 into contact with the plurality of outer pins 23. The outer peripheral surface 81 of the support 8 may be separated from the plurality of outer pins 23.

Further, regarding the device for the inner ring 61A, in the gear device 1A, the inner ring 61A may have the first inner ring 601 and the second inner ring 602. For example, the inner ring 61A is divided into three or more parts. May be good. That is, as an example, the inner ring 61A may be divided into three parts by having a third inner ring in addition to the first inner ring 601 and the second inner ring 602.

Further, the plurality of holes into which the plurality of positioning pins 65 are press-fitted may be formed from the first inner ring 601 to the second inner ring 602, and the inner ring 61A may not penetrate in the direction parallel to the rotation axis Ax1. good. For example, the positioning pin 65 may be press-fitted into a hole formed from the side of the second inner ring 602 facing the first inner ring 601 to the middle of the thickness of the second inner ring 602. In this case, the lubricant is prevented from leaking through the hole for press-fitting the positioning pin 65.

Further, regarding the device for the outer ring 62A, the outer ring 62A of the bearing member 6A does not have to be completely seamless in the direction parallel to the gear body 22 and the rotating shaft Ax1. That is, the method for manufacturing the gear device 1A may include a step of integrally forming the outer ring 62A and the gear body 22 by processing one base material. Specifically, for example, the outer ring 62A and the gear body 22 may be integrally formed by processing a single base material in which two types of metal ingots are joined (integrated) by pressure bonding or adhesion. In this case, since a seam is generated at the joint portion of the two types of metal ingots, the same effect as the seamlessly continuous outer ring 62A and the gear body 22 can be expected, although it is not completely seamless.

(Embodiment 2)
In the inscribed meshing planetary gear device 1B (hereinafter, also simply referred to as “gear device 1B”) according to the present embodiment, as shown in FIGS. 19A and 19B, the detailed shape of the inner ring 61A of the bearing member 6A is the embodiment. It is different from the gear device 1A according to 1. FIG. 19B is a diagram showing only a main part of the first inner ring 601 in the A1-A1 line cross section of FIG. 19A. Hereinafter, the same configurations as those in the first embodiment will be designated by a common reference numeral and description thereof will be omitted as appropriate.

In the gear device 1B according to the present embodiment, a diameter-expanded portion 691 that widens the opening area of each of the plurality of holding holes 611 is formed on the surface of the first inner ring 601 opposite to the second inner ring 602. Specifically, as shown in FIG. 19A, the enlarged diameter portion 691 is a chamfered portion formed on the peripheral edge of the opening of the holding hole 611 on the input side (left side of FIG. 19A) of the rotation shaft Ax1 of the first inner ring 601. It is composed of. Here, the diameter-expanded portion 691 is formed in a tapered shape (C-plane shape) so that the opening area of the holding hole 611 increases as the distance from the second inner ring 602 increases. In the present embodiment, such an enlarged diameter portion 691 is formed corresponding to all the holding holes 611, respectively. The diameter-expanded portion 691 is not limited to the tapered shape (C-plane shape), and may be, for example, a curved R-plane shape, a stepped counterbore shape, or the like.

By forming such an enlarged diameter portion 691, the gap between the inner pin 4 and the inner pin 4 is expanded on the opening surface of at least each of the plurality of holding holes 611 on the side opposite to the second inner ring 602. Take shape. As a result, the gap between the inner peripheral surface of the holding hole 611 and the inner pin 4 created by the enlarged diameter portion 691 functions as an "oil pool" for storing the lubricant (lubricating oil). Since the enlarged diameter portion 691 is continuous with the holding hole 611, the lubricant stored in the enlarged diameter portion 691 is drawn into the gap between the inner peripheral surface of the holding hole 611 and the inner pin 4 by, for example, a capillary phenomenon. It acts to smooth the rotation (rotation) of the inner pin 4.

Further, the enlarged diameter portion 691 as an "oil pool" is located on the lubricant circulation path RL1 as shown in FIG. Therefore, a part of the circulation path RL1 is used as a “lubricant” path, and the lubricant in the enlarged diameter portion 691 is supplied to at least one of the outer pin 23 and the rolling element 63 other than the inner pin 4. be able to. In particular, in the present embodiment, as shown in FIG. 20, since the outer pin 23 and the rolling element 63 are both located on the circulation path RL1, the lubricant held in the enlarged diameter portion 691 is applied to the outer pin 23. And can be supplied to both the rolling elements 63.

Further, in the present embodiment, as shown in FIGS. 19A and 19B, a connecting groove 692 is formed on the facing surfaces 601A and 602A of at least one of the first inner ring 601 and the second inner ring 602 with the other. .. The connecting groove 692 connects the space accommodating each of the plurality of rolling elements 63 and each of the plurality of holding holes 611. That is, the connecting groove 692 is provided on at least one of the facing surface 601A and the facing surface 602A, which are the dividing surfaces of the first inner ring 601 and the second inner ring 602, and the rolling element 63 between the inner ring 61A and the outer ring 62A. The space for accommodating each is connected to the holding hole 611. In the present embodiment, as an example, a connecting groove 692 is formed on the surface 601A of the first inner ring 601 facing the second inner ring 602 along the radial direction of the inner ring 61A. In this embodiment, such connecting grooves 692 are formed corresponding to all the holding holes 611, respectively.

The connecting groove 692 functions as a path through which the lubricant (lubricating oil) passes. In this embodiment, as shown in FIG. 20, the connecting groove 692 constitutes a part of the lubricant circulation path RL1. In the present embodiment, as an example, as shown in FIG. 19B, the connecting groove 692 has a rectangular cross-sectional shape orthogonal to the radial direction of the inner ring 61A. The depth D4 (from the facing surface 601A) of the connecting groove 692 and the width D5 of the connecting groove 692 are 1/10 (φ10 × 1/10) or more (φ10 × 1/10) or more (φ10 × 2) of the diameter φ10 of the outer pin 23, respectively. ) The following is preferable. As an example, when the diameter φ10 of the outer pin 23 is about 2.5 mm, the depth D4 and the width D5 of the connecting groove 692 are preferably 0.25 mm or more and 5.0 mm or less. In the example of FIG. 20, the depth D4 of the connecting groove 692 is smaller than the width D5 of the connecting groove 692, but the present invention is not limited to this example, and the depth D4 of the connecting groove 692 may be the width D5 or more. Further, the cross-sectional shape of the connecting groove 692 is not limited to a rectangular shape, but may be a semicircular shape, a triangular shape, or another polygonal shape.

By providing such a connecting groove 692, the lubricant easily circulates in the lubricant holding space 17 through the connecting groove 692. In particular, the connecting groove 692 is connected to a space for accommodating the rolling element 63 between the inner ring 61A and the outer ring 62A. Therefore, when the bearing member 6A operates and the rolling element 63 rotates, the rolling element 63 functions as a pump, and the lubricant in the lubricant holding space 17 is positively circulated via the connecting groove 692. Is possible. As a result, the lubricant in the lubricant holding space 17 is easily circulated, and even during long-term use of the gear device 1B, the lubricant is easily distributed throughout the lubricant holding space 17, and is transmitted in the gear device 1B. Problems such as reduced efficiency are less likely to occur.

Further, by providing the connecting groove 692, the effect of lowering the internal pressure in the space between the oil seal 16 and the rolling element 63 can be expected. That is, the space between the oil seal 16 and the rolling element 63 is connected to the holding hole 611 by the connecting groove 692, so that the space between the oil seal 16 and the rolling element 63 is expanded, so that the rolling element 63 can be used. When functioning as a pump, it leads to suppression of the rise in internal pressure. As a result of suppressing the increase in the internal pressure of the lubricant holding space 17, for example, leakage of the lubricant beyond the oil seal 16 is less likely to occur.

As a modification of the second embodiment, the connecting groove 692 may be formed on the facing surfaces 601A and 602A of both the first inner ring 601 and the second inner ring 602. Further, the connecting groove 692 may be formed only on the facing surface 602A of the second inner ring 602.

As another modification of the second embodiment, the enlarged diameter portion 691 and the connecting groove 692 may be adopted individually. That is, the gear device 1B may have only the enlarged diameter portion 691 among the enlarged diameter portion 691 and the connecting groove 692, or conversely, may have only the connecting groove 692.

The configuration of the second embodiment (including the modified example) can be appropriately combined with the configuration (including the modified example) described in the first embodiment.

(summary)
As described above, the inscribed meshing planetary gear device (1,1A, 1B) according to the first aspect includes a bearing member (6,6A), an internal gear (2), and a planetary gear (3). , With a plurality of inner pins (4). The bearing member (6,6A) includes an outer ring (62,62A), an inner ring (61,61A) arranged inside the outer ring (62,62A), and an outer ring (62,62A) and an inner ring (61,61A). It has a plurality of rolling elements (63) arranged between the wheels, and the inner ring (61, 61A) is rotatably supported about the rotation axis (Ax1) with respect to the outer ring (62, 62A). .. The internal gear (2) is held by the annular gear body (22) and the inner peripheral surface (221) of the gear body (22) in a rotatable state, and a plurality of external pins (21) constituting the internal tooth (21). 23) and. The planetary gear (3) has external teeth (31) that partially mesh with the internal teeth (21). The plurality of internal pins (4) are inserted into the plurality of free fitting holes (32) formed in the planetary gears (3), and the internal tooth gears (2) revolve in the free fitting holes (32). ) Revolves relative to. The outer ring (62, 62A) is seamlessly and continuously provided in the direction parallel to the gear body (22) and the rotation axis (Ax1).

According to this aspect, it becomes easy to improve the accuracy of centering between the internal gear (2) and the bearing member (6, 6A). That is, the center of the gear body (22) of the internal gear (2) and the center of the outer ring (62, 62A) of the bearing member (6, 6A) can be easily maintained on the rotating shaft (Ax1) with high accuracy. .. As a result, the inscribed meshing planetary gear device (1,1A, 1B) has an advantage that problems such as vibration due to poor centering and a decrease in transmission efficiency are unlikely to occur.

In the inscribed meshing planetary gear device (1,1A, 1B) according to the second aspect, in the first aspect, the inner diameter (φ3) of the outer ring (62,62A) is the diameter (φ2) of the virtual circle (VC1). Is different. The virtual circle (VC1) is a virtual circle that passes through the bottom of a plurality of pin holding grooves (223) in which a plurality of outer pins (23) are held on the inner peripheral surface (221) of the gear body (22).

According to this aspect, the gear body (22) and the outer ring (62, 62A) are seamlessly continuous, but the function of the gear body (22) and the outer ring (62, 62A) is performed by the difference in the inner diameters of the two. It will be easier to separate clearly.

In the inscribed meshing planetary gear device (1,1A, 1B) according to the third aspect, in the second aspect, the inner diameter (φ3) of the outer ring (62,62A) is the diameter (φ2) of the virtual circle (VC1). Greater.

According to this aspect, it is possible to avoid interference between the outer pin (23) held on the inner peripheral surface (221) of the gear body (22) and the inner peripheral surface (620) of the outer ring (62, 62A).

In the inscribed meshing planetary gear device (1,1A, 1B) according to the fourth aspect, in any one of the first to third aspects, the inner peripheral surface (620) of the outer ring (62, 62A) and the gear body (22). ), A holding recess (67) is arranged between the inner peripheral surface (221) and the inner peripheral surface (221).

According to this aspect, the holding recess (67) functions as an "oil pool" for storing the lubricant, and the lubricant is less likely to be exhausted.

In the fourth aspect, the inscribed meshing planetary gear device (1,1A, 1B) according to the fifth aspect has a plurality of outer pins (23) from the holding recess (67) to each of the plurality of inner pins (4). ), And further provided with a lubricant path leading to at least one of the plurality of rolling elements (63).

According to this aspect, the lubricant held in the holding recess (67) is supplied to at least one of the inner pin (4), the outer pin (23), and the rolling element (63), and the movement thereof. Can be smoothed.

In the inscribed meshing planetary gear device (1,1A, 1B) according to the sixth aspect, in any one of the first to fifth aspects, the outer peripheral surface (680) of the outer ring (62, 62A) is the gear body (22). ) Consists of a pressure receiving surface that receives a larger stress than the outer peripheral surface (224).

According to this aspect, stress from the outside can be received on the outer ring (62, 62A) side having high rigidity, and the resistance to the stress of the inscribed meshing planetary gear device (1, 1A, 1B) as a whole becomes high. ..

In the inscribed meshing planetary gear device (1,1A, 1B) according to the seventh aspect, in the sixth aspect, the pressure receiving surface is stressed from the exterior body fitted to the outer periphery of the outer ring (62,62A). Works.

According to this aspect, when the exterior body is fitted to the outer periphery of the outer ring (62, 62A), the stress from the exterior body can be received on the side of the outer ring (62, 62A) having high rigidity, and the inner ring is inscribed. The resistance to stress of the meshing planetary gear device (1,1A, 1B) as a whole is increased.

In the inscribed meshing planetary gear device (1,1A, 1B) according to the eighth aspect, in any one of the first to seventh aspects, each of the plurality of inner pins (4) is in a state where the inner ring (4) can rotate. It is held at 61, 61A).

According to this aspect, since each of the plurality of inner pins (4) is held by the inner ring (61, 61A) in a state in which the inner pin (4) can rotate, the inner pin (4) revolves in the free fitting hole (32). At that time, the inner pin (4) itself can rotate. Therefore, even if an inner roller mounted on the inner pin (4) and rotatable around the inner pin (4) is not used, the inner peripheral surface (321) and the inner pin (4) of the free fitting hole (32) can be connected to each other. The loss due to the frictional resistance between them can be reduced. Therefore, the inner roller is not indispensable, and there is an advantage that it is easy to miniaturize.

In the inscribed meshing planetary gear device (1,1A, 1B) according to the ninth aspect, in any one of the first to eighth aspects, the inner ring (61, 61A) is in a direction parallel to the rotation axis (Ax1). Includes a first inner ring (601) and a second inner ring (602) that face each other. The first inner ring (601) has a plurality of holding holes (611) through which the plurality of inner pins (4) each pass in a direction parallel to the rotation axis (Ax1).

According to this aspect, there may be a slight gap between the first inner ring (601) and the second inner ring (602). By creating such a gap, for example, the lubricant can be easily supplied to the inner pin (4) or the like through the gap. Therefore, as compared with the case where the inner ring (61, 61A) is not divided into the first inner ring (601) and the second inner ring (602), for example, in the inscribed meshing planetary gear device (1, 1A, 1B). Even during long-term use, the lubricant is likely to spread throughout, and problems such as a decrease in transmission efficiency in the inscribed meshing planetary gear device (1,1A, 1B) are less likely to occur.

The inscribed meshing planetary gear device (1,1A, 1B) according to the tenth aspect further includes a lubricant circulation path (RL1) in the ninth aspect. The lubricant circulation path (RL1) has at least a gap between the first inner ring (601) and the second inner ring (602), a space for accommodating each of the plurality of rolling elements (63), and a plurality of holding holes (611). ) And each of them.

According to this aspect, the lubricant is easily circulated through the rolling element (63) and the inner pin (4).

In the inward meshing planetary gear apparatus (1,1A, 1B) according to the eleventh aspect, in any one of the first to tenth aspects, the planetary gear (3) faces the rotation axis (Ax1) in a direction parallel to the rotation axis (Ax1). The first planetary gear (301) and the second planetary gear (302) are included.

According to this aspect, by balancing the weight between the first planetary gear (301) and the second planetary gear (302), it is easy to suppress problems such as vibration generation and deterioration of transmission efficiency.

The method for manufacturing the internal meshing planetary gear device (1,1A, 1B) according to the twelfth aspect is as follows: a bearing member (6, 6A), an internal gear (2), a planetary gear, and a plurality of internal pins (1, 1A, 1B). 4) is a method for manufacturing an internal meshing planetary gear device (1,1A, 1B) including the above. The bearing member (6,6A) has an inner ring (61,61A) arranged inside the outer ring (62,62A) and the outer ring (62,62A), and the inner ring (61,61A) is the outer ring (62,62A). ) Is rotatably supported relative to the rotation axis (Ax1). The internal gear (2) has an annular gear body (22) and a plurality of external pins (23) held on the inner peripheral surface of the gear body (22) in a rotatable state to form internal teeth. .. Planetary gears have external teeth that partially mesh with the internal teeth. The plurality of internal pins (4) are inserted into the plurality of idle fitting holes (32) formed in the planetary gears, and the plurality of internal pins (4) revolve in the free fitting holes (32) with respect to the internal tooth gear (2). Rotates relatively. The manufacturing method includes a step of integrally forming the outer ring (62, 62A) and the gear body (22) by processing one base material.

According to this aspect, it becomes easy to improve the accuracy of centering between the internal gear (2) and the bearing member (6, 6A). That is, the center of the gear body (22) of the internal gear (2) and the center of the outer ring (62, 62A) of the bearing member (6, 6A) can be easily maintained on the rotating shaft (Ax1) with high accuracy. .. As a result, the inscribed meshing planetary gear device (1,1A, 1B) has an advantage that problems such as vibration due to poor centering and a decrease in transmission efficiency are unlikely to occur.

1,1A, 1B Internal meshing planetary gear device 2 Internal tooth gear 3 Planetary gear 4 Internal pin 6,6A Bearing member 21 Internal tooth 22 Gear body 23 External pin 31 External tooth 32 Free fitting hole 61, 61A Inner ring 62, 62A Outer ring 63 Rolling element 67 Holding recess 103 Tire (exterior body)
221 Inner peripheral surface (of gear body) 223 Pin holding groove 224 Outer peripheral surface (of gear body) 301 1st planetary gear 302 2nd planetary gear 601 1st inner ring 602 2nd inner ring 611 Holding hole 620 Inner peripheral surface (of outer ring) 680 (outer ring) outer peripheral surface (pressure receiving surface)
Ax1 Rotating axis RL1 Circulation path VC1 Virtual circle φ2 (virtual circle) diameter φ3 (outer ring) inner diameter

Claims (12)

It has an outer ring, an inner ring arranged inside the outer ring, and a plurality of rolling elements arranged between the outer ring and the inner ring, and the inner ring rotates relative to the outer ring about a rotation axis. Bearing members that can be supported and
An internal gear having an annular gear body and a plurality of external pins held on the inner peripheral surface of the gear body in a rotatable state to form internal teeth.
A planetary gear having external teeth that partially mesh with the internal teeth,
It is provided with a plurality of internal pins that rotate relative to the internal gear while revolving in the free fitting holes in a state of being inserted into the plurality of free fitting holes formed in the planetary gear.
The outer ring is seamlessly and continuously provided in a direction parallel to the gear body and the rotation axis.
Inscribed meshing planetary gear device. The inner diameter of the outer ring is different from the diameter of the virtual circle passing through the bottom of the plurality of pin holding grooves in which the plurality of outer pins are held on the inner peripheral surface of the gear body.
The inscribed meshing planetary gear device according to claim 1. The inner diameter of the outer ring is larger than the diameter of the virtual circle.
The inscribed meshing planetary gear device according to claim 2. A holding recess is arranged between the inner peripheral surface of the outer ring and the inner peripheral surface of the gear body.
The inscribed meshing planetary gear device according to any one of claims 1 to 3. Further comprising a lubricant path from the holding recess to each of the plurality of inner pins, each of the plurality of outer pins, and at least one of the plurality of rolling elements.
The inscribed meshing planetary gear device according to claim 4. The outer peripheral surface of the outer ring constitutes a pressure receiving surface that receives a larger stress than the outer peripheral surface of the gear body.
The inscribed meshing planetary gear device according to any one of claims 1 to 5. Stress from the exterior body fitted to the outer circumference of the outer ring acts on the pressure receiving surface.
The inscribed meshing planetary gear device according to claim 6. Each of the plurality of inner pins is held by the inner ring in a state in which it can rotate.
The inscribed meshing planetary gear device according to any one of claims 1 to 7. The inner ring includes a first inner ring and a second inner ring facing each other in a direction parallel to the rotation axis.
The first inner ring has a plurality of holding holes through which the plurality of inner pins each pass in a direction parallel to the rotation axis.
The inscribed meshing planetary gear device according to any one of claims 1 to 8. Further provided with at least a gap between the first inner ring and the second inner ring, a space for accommodating each of the plurality of rolling elements, and a circulation path for a lubricant passing through each of the plurality of holding holes.
The inscribed meshing planetary gear device according to claim 9. The planetary gears include a first planetary gear and a second planetary gear facing in a direction parallel to the axis of rotation.
The inscribed meshing planetary gear device according to any one of claims 1 to 10. A bearing member having an outer ring and an inner ring arranged inside the outer ring, and the inner ring being rotatably supported with respect to the outer ring about a rotation axis.
An internal gear having an annular gear body and a plurality of external pins held on the inner peripheral surface of the gear body in a rotatable state to form internal teeth.
A planetary gear having external teeth that partially mesh with the internal teeth,
An internal connection including a plurality of internal pins that rotate relative to the internal gear while revolving in the free fitting holes, respectively, in a state of being inserted into the plurality of free fitting holes formed in the planetary gear. It is a method of manufacturing a meshing planetary gear device.
It has a step of integrally forming the outer ring and the gear body by processing one base material.
A method for manufacturing an inscribed meshing planetary gear device.

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