Speed reducer and robot

Abstract

The present technology pertains to: a speed reducer in which both low backlash and high efficiency of a planetary reduction gear can be achieved; and a robot. A speed reducer according to the present technology comprises: a sun gear; a plurality of planetary gears meshing with the sun gear and an internal gear; the internal gear having a first phase determination unit for fixing the phase of the internal gear; and a support unit having a plurality of second phase determination units that are fitted to the first phase determination unit. The present technology can be applied to, for example, a robot having a joint drive unit.

Description

Reducers and robots

[0001] The present technology relates to a reducer and a robot, and more particularly to a reducer and a robot that can suitably achieve both low backlash and high efficiency of a planetary reducer.

[0002] Planetary reducers are required to achieve both low backlash and high efficiency. To achieve low backlash, it is necessary to reduce or eliminate the gap between the gears. However, reducing the gap between the gears causes the tooth contact between the gears to deteriorate due to the influence of processing errors, resulting in reduced efficiency.

[0003] Patent Document 1 describes a planetary gear transmission in which the planetary gears, sun gear, and internal gear are tapered gears and equipped with a mechanism that uses disc springs to apply axial preload so as to eliminate gaps between the gears.

[0004] Japanese Patent Application Publication No. 6-272740

[0005] Adding a mechanism to absorb gear processing errors, as in the technology described in Patent Document 1, increases the size of the planetary reducer and increases costs. Also, combining various gears by matching them to the actual parts when assembling the planetary reducer in order to absorb gear processing errors increases the number of assembly steps.

[0006] The present technology has been made in view of such circumstances, and makes it possible to preferably achieve both low backlash and high efficiency in a planetary reducer.

[0007] A reducer according to a first aspect of the present technology includes a sun gear, a plurality of planetary gears meshing with the sun gear and the internal gear, the internal gear having a first phase determining portion formed thereon that fixes the phase of the internal gear, and a support portion having a plurality of second phase determining portions that fit into the first phase determining portions.

[0008] A robot according to a second aspect of the present technology has a reducer including a sun gear, a plurality of planetary gears meshing with the sun gear and the internal gear, the internal gear having a first phase determining portion formed thereon that fixes the phase of the internal gear, and a support portion having a plurality of second phase determining portions that fit into the first phase determining portions.

[0009] In the first and second aspects of the present technology, a plurality of planetary gears are meshed with a sun gear and an internal gear, a first phase determining portion that fixes the phase of the internal gear is formed on the internal gear, and a plurality of second phase determining portions that fit into the first phase determining portions are formed on a support portion.

[0010] 1 is a diagram illustrating a first configuration example of a planetary reducer according to an embodiment of the present technology; FIG. 2 is a cross-sectional view illustrating a configuration example of a carrier unit; FIG. 3 is a diagram illustrating a second configuration example of a planetary reducer according to an embodiment of the present technology; FIG. 4 is a cross-sectional view illustrating a configuration example of a carrier unit; FIG. 5 is a diagram illustrating a third configuration example of a planetary reducer according to an embodiment of the present technology; FIG. 6 is a diagram illustrating an example of the appearance of an internal gear; FIG. 7 is a diagram illustrating an example of a main body unit and an output shaft to which an internal gear is assembled; FIG. 8 is a diagram illustrating an orientation of a front-stage internal gear to be assembled to a main body unit; FIG. 9 is a diagram illustrating an example of a fixing means for the internal gear; FIG. 10 is a diagram illustrating another example of a fixing means for the internal gear; FIG. 11 is a diagram illustrating an example of a main body unit and an output shaft to which an internal gear having four phase determining portions is assembled; FIG. 12 is a diagram illustrating an orientation of a front-stage internal gear to be assembled to a main body unit;

[0011] Hereinafter, embodiments of the present technology will be described in the following order: 1. Configuration of planetary reducer 2. Modification 3. Application example

[0012] 1. Configuration of Planetary Reducer FIG. 1 is a diagram illustrating a first configuration example of a planetary reducer 1 according to an embodiment of the present technology.

[0013] The planetary reducer 1 shown in Fig. 1 is a two-stage planetary gear reducer equipped with a front-stage planetary gear mechanism and a rear-stage planetary gear mechanism. As shown in Fig. 1, the planetary reducer 1 is composed of a main body 11, a front-stage internal gear 12A, a rear-stage internal gear 12B, a carrier 13, an output shaft 14, and a cross roller unit 15.

[0014] The front-stage internal gear 12A is assembled and fixed to the main body 11. The main body 11 functions as a (front-stage) support part that supports the front-stage internal gear 12A. The front-stage internal gear 12A meshes with the front-stage planetary gear of the carrier part 13.

[0015] The carrier portion 13 has two planetary gears. The planetary gears provided on the carrier portion 13 are configured by integrally forming a front planetary gear and a rear planetary gear that are coaxial with each other.

[0016] The rear-stage internal gear 12B is assembled and fixed to the output shaft 14. The output shaft 14 functions as a (rear-stage) support portion that supports the rear-stage internal gear 12B. The rear-stage internal gear 12B rotates by meshing with the rear-stage planetary gear of the carrier portion 13, and as the rear-stage internal gear 12B rotates, the output shaft 14 also rotates. In the following, when there is no need to particularly distinguish between the front-stage internal gear 12A and the rear-stage internal gear 12B, they will simply be referred to as the internal gear 12.

[0017] An end of the output shaft 14 is inserted into a hole provided in the cross roller unit 15. The cross roller unit 15 supports the output shaft 14.

[0018] FIG. 2 is a cross-sectional view showing an example of the configuration of the carrier portion 13. As shown in FIG.

[0019] As shown in FIG. 2 , in the carrier portion 13 , a sun gear 32 is connected to the input shaft 31 .

[0020] The planetary gear 33-1 is formed by integrating a front planetary gear 33-1A and a rear planetary gear 33-2B, and the planetary gear 33-2 is formed by integrating a front planetary gear 33-1A and a rear planetary gear 33-2B. The front planetary gears 33-1A and 33-2A rotate by meshing with the sun gear 32, and transmit the driving force transmitted from the input shaft 31 to the rear internal gear 12B (output shaft 14) which meshes with the rear planetary gears 33-1B and 33-2B.

[0021] FIG. 3 is a diagram illustrating a second configuration example of the planetary reducer 1 according to an embodiment of the present technology.

[0022] The planetary reducer 1 in Fig. 3 is a two-stage planetary gear reducer, similar to the planetary reducer 1 described with reference to Fig. 1. In Fig. 3, the same components as those in Fig. 1 are assigned the same reference numerals. Duplicate explanations will be omitted where appropriate. The planetary reducer 1 in Fig. 3 differs from the planetary reducer 1 in Fig. 1 in that a carrier portion 51 is provided instead of the carrier portion 13.

[0023] The front-stage internal gear 12A meshes with the front-stage planetary gear of the carrier portion 51.

[0024] The carrier part 51 has three planetary gears. The planetary gears provided on the carrier part 51 are configured by integrally forming a front planetary gear and a rear planetary gear that are coaxial with each other.

[0025] The rear-stage internal gear 12B rotates by meshing with the rear-stage planetary gear of the carrier portion 51, and as the rear-stage internal gear 12B rotates, the output shaft 14 also rotates.

[0026] FIG. 4 is a cross-sectional view showing an example of the configuration of the carrier portion 51. As shown in FIG.

[0027] As shown in FIG. 4 , in the carrier portion 51 , a sun gear 62 is connected to an input shaft 61 .

[0028] The planetary gear 63-1 is formed by integrating a front-stage planetary gear 63-1A and a rear-stage planetary gear 63-2B. The planetary gear 63-2 (not shown) is formed by integrating a front-stage planetary gear 63-1A and a rear-stage planetary gear 63-2B, and the planetary gear 63-3 is formed by integrating a front-stage planetary gear 63-3A and a rear-stage planetary gear 63-3B. The front-stage planetary gears 63-1A, 63-2A, and 63-3A rotate by meshing with the sun gear 62, and transmit the driving force transmitted from the input shaft 61 to the rear-stage internal gear 12B (output shaft 14) which meshes with the rear-stage planetary gear 63-1B, 63-2B, and 63-3B.

[0029] FIG. 5 is a diagram illustrating a third configuration example of the planetary reducer 1 according to an embodiment of the present technology.

[0030] 5 is a single-stage planetary gear reducer equipped with a single-stage planetary gear mechanism. As shown in Fig. 5, the planetary reducer 1 is composed of an input shaft 81, a sun gear 82, three planetary gears 83-1 to 83-3, an internal gear 84, a planet carrier 85, and an output shaft 86.

[0031] A sun gear 62 is connected to the input shaft 61, and three planetary gears 83-1 to 83-3 mesh with the sun gear 62. The three planetary gears 83-1 to 83-3 mesh with an internal gear 84. The internal gear 84 is assembled and fixed to a main body (not shown).

[0032] The three planetary gears 83-1 to 83-3 are connected by a planetary carrier 85, and an output shaft 86 is connected to the planetary carrier 85. The three planetary gears 83-1 to 83-3 rotate by meshing with the sun gear 62, and transmit the driving force transmitted from the input shaft 61 to the planetary carrier 85 (output shaft 86).

[0033] FIG. 6 is a diagram showing an example of the appearance of the internal gear 12.

[0034] The internal gear 12 in Fig. 6 is an involute gear having a cylindrical shape and teeth formed on the inner circumference to mesh with the teeth of the planetary gears. The module of the internal gear 12 is arbitrary, and the internal gear 12 may be a profile shifted gear or a standard gear.

[0035] The outer periphery of the cylindrical portion of the internal gear 12 is formed with a phase determining portion 101-1 that fits into a phase determining portion provided on the main body portion 11 or the output shaft 14. For example, a recess is formed as the phase determining portion on the main body portion 11 or the output shaft 14. The phase determining portion 101-1 has a convex shape that conforms to the concave shape of the phase determining portion on the main body portion 11 or the output shaft 14 side. Specifically, the circumferential width of the phase determining portion 101-1 is approximately the same as the circumferential width of the phase determining portion on the main body portion 11 or the output shaft 14 side. The circumferential width of the phase determining portion 101-1 is arbitrary. Because the phase determining portion 101-1 receives a load in the rotational direction, it is desirable to determine the width of the phase determining portion 101-1 based on the torque capacity. The phase determining portion 101-1 is formed with a notch 102 that functions as a marker for identifying the reference phase determining portion 101-1.

[0036] Furthermore, a phasing portion 101-2 is formed on the outer periphery of the cylindrical portion of the internal gear 12, at a position symmetrical to the phasing portion 101-1 with respect to the center of the internal gear 12. The phasing portion 101-2 is shaped similarly to the phasing portion 101-1, but does not have the notch 102. In the following description, when there is no need to particularly distinguish between the phasing portion 101-1 and the phasing portion 101-2, they will simply be referred to as the phasing portion 101.

[0037] In this way, one or more phasing portions 101 are formed on the outer periphery of the cylindrical portion of the internal gear 12. When multiple phasing portions 101 are formed on the internal gear 12, the multiple phasing portions 101 are arranged at equal intervals along the outer periphery of the cylindrical portion of the internal gear 12, and a mark is formed on the internal gear 12 to identify at least one of the multiple phasing portions 101.

[0038] The outer diameter of the cylindrical portion of the internal gear 12 approximately matches the diameter of the openings provided in the main body 11 and the output shaft 14, and the cylindrical portion of the internal gear 12 is fitted into the openings on the main body 11 and the output shaft 14 side. The internal gear 12 is formed with high precision so that the center of the internal gear 12 is coaxial with the input shaft and the output shaft 14.

[0039] The internal gear 84 provided in the single-stage planetary gear reducer also has a shape similar to that of the internal gear 12 .

[0040] FIG. 7 is a diagram showing an example of the main body 11 and output shaft 14 to which the internal gear 12 is attached.

[0041] As shown in A of Figure 7, the main body 11 is formed with an opening 120 into which the cylindrical portion of the front-stage internal gear 12A is fitted, and four phase determination portions (recesses) 121-1 to 121-4 into which the phase determination portion 101 is fitted.

[0042] The opening 120 is formed, for example, to a predetermined depth that does not penetrate the main body 11. As described above, the diameter of the opening 120 approximately matches the outer diameter of the cylindrical portion of the front-stage internal gear 12A, so that the opening 120 and the cylindrical portion of the front-stage internal gear 12A are fitted together with high precision.

[0043] The four phasing portions 121-1 to 121-4 are formed along the circumference of the opening 120. In other words, the phasing portions 121-1 to 121-4 are formed on the edge of the opening 120. The phasing portions 121-1 and 121-3 are formed at positions symmetrical with respect to the center of the main body 11, and the phasing portions 121-2 and 121-4 are formed at positions symmetrical with respect to the center of the main body 11. In the following, when there is no need to particularly distinguish between the phasing portions 121-1 to 121-4, they will be simply referred to as phasing portions 121.

[0044] As described above, the circumferential width of the phasing portion 121 is approximately the same as the circumferential width of the phasing portion 101 on the front-stage internal gear 12A side, so the phasing portions 101 and 121 are fitted together with high precision. In the example of A in Fig. 7, the phasing portion 101-1 is fitted into the phasing portion 121-1, and the phasing portion 101-3 is fitted into the phasing portion 121-3. On the other hand, the phasing portion 101 on the front-stage internal gear 12A side is not fitted into the phasing portions 121-2 and 121-4.

[0045] In this way, the number of phasing portions 121 formed in the main body 11 is equal to or greater than the number of phasing portions 101 on the front-stage internal gear 12A side. When multiple phasing portions 121 are formed in the main body 11, the multiple phasing portions 121 are arranged at equal intervals along the circumference of the opening 120.

[0046] As shown in FIG. 7B, the output shaft 14 is formed with an opening 130 into which the cylindrical portion of the rear-stage internal gear 12B is fitted, and four phase determining portions (recesses) 131-1 to 131-4 into which the phase determining portions 101 are fitted.

[0047] The opening 130 is formed, for example, to a predetermined depth that does not penetrate the output shaft 14. As described above, the diameter of the opening 130 approximately matches the outer diameter of the cylindrical portion of the rear-stage internal gear 12B, so that the opening 130 and the cylindrical portion of the rear-stage internal gear 12B are fitted together with high precision.

[0048] The four phasing portions 131-1 to 131-4 are formed along the circumference of the opening 130. In other words, the phasing portions 131-1 to 131-4 are formed on the edge portions of the circumference of the opening 130. The phasing portions 131-1 and 131-3 are formed at positions symmetrical with respect to the center of the output shaft 14, and the phasing portions 131-2 and 131-4 are formed at positions symmetrical with respect to the center of the output shaft 14. In the following, when there is no need to particularly distinguish between the phasing portions 131-1 to 131-4, they will be simply referred to as phasing portions 131.

[0049] As described above, the circumferential width of the phasing portion 131 is approximately the same as the circumferential width of the phasing portion 101 on the rear-stage internal gear 12B side, so the phasing portion 101 and the phasing portion 131 are fitted together with high precision. In the example of Fig. 7B, the phasing portion 101-1 is fitted into the phasing portion 131-1, and the phasing portion 101-3 is fitted into the phasing portion 131-3. On the other hand, the phasing portion 101 on the rear-stage internal gear 12B side is not fitted into the phasing portions 131-2 and 131-4.

[0050] In this way, the output shaft 14 is formed with a number of phasing portions 131 equal to or greater than the number of phasing portions 101 on the rear-stage internal gear 12B side, similar to the main body portion 11. When a plurality of phasing portions 131 are formed on the output shaft 14, the plurality of phasing portions 131 are arranged at equal intervals around the circumference of the opening 130.

[0051] FIG. 8 is a diagram illustrating the orientation of the front-stage internal gear 12A to be assembled to the main body 11. As shown in FIG.

[0052] As shown in Figure 8, there are four possible phases (orientations) of the front-stage internal gear 12A when it is assembled to the main body 11, depending on which of the phase determining portions 121-1 to 121-4 on the main body 11 the phase determining portion 101-1 on the front-stage internal gear 12A is fitted to.

[0053] An operator assembling the planetary reducer 1 can determine the optimum phase from among the four phases of the front-stage internal gear 12A while checking the meshing with other gears such as the planetary gears of the carrier portion 13 by actual fitting, and then assemble the front-stage internal gear 12A to the main body portion 11. Specifically, the phase of the front-stage internal gear 12A is fixed by fitting the phase determining portion 101 on the front-stage internal gear 12A side with the phase determining portion 121 of the main body portion 11. Similarly, an operator can determine the optimum phase from among the four phases of the rear-stage internal gear 12B while checking the meshing with other gears by actual fitting, and then assemble the rear-stage internal gear 12B to the output shaft 14.

[0054] As described above, in the present technology, the phasing portion 101 (first phasing portion) that fixes the phase of the internal gear 12 is formed on the internal gear 12, and a plurality of phasing portions (second phasing portions) that fit into the phasing portion 101 on the internal gear 12 are formed on the main body 11 and the output shaft 14, respectively. This makes it possible to adjust the phase of the internal gear 12. By adjusting the phase of the internal gear 12, an operator can assemble the gears so as to reduce or eliminate gaps between the gears while absorbing machining errors of the gears and parts. Because machining errors of the gears and parts are absorbed, low backlash can be achieved and a decrease in efficiency due to the influence of machining errors can be prevented.

[0055] Therefore, it is possible to achieve both low backlash and high efficiency in the planetary reducer 1 without the need to prototype a large number of gears and find the optimal gear combination by matching them to the actual parts, and without the need to implement an additional mechanism for absorbing processing errors in the gears, etc.

[0056] FIG. 9 is a diagram showing an example of a fixing means for the internal gear 12.

[0057] After the optimum assembly phase of the internal gear 12 is determined, the internal gear 12 is completely fixed to the main body 11 and the output shaft 14 .

[0058] 9A, screws 151 are used to fix the rear-stage internal gear 12B and the output shaft 14. If the surface of the output shaft 14 on which the opening 130 and the phase determining portion 131 are formed is considered to be the back surface, screws 151 are inserted from the front surface side of each of the phase determining portions 131-1 and 131-3, and the output shaft 14 and the phase determining portions 101-1 and 101-3 of the rear-stage internal gear 12B are fastened together.

[0059] 9B, the main body 11 and the front-stage internal gear 12A are fixed together using screws 151. If the surface of the main body 11 on which the opening 120 and the phasing portion 121 are formed is considered the back surface, screws 151 are inserted from the front surface side of each of the phasing portions 121-1 and 121-3, fastening the main body 11 to the phasing portions 101-1 and 101-3 of the front-stage internal gear 12A.

[0060] FIG. 10 is a diagram showing another example of the fixing means for the internal gear 12. In FIG.

[0061] In the example of Fig. 10A, adhesive is used to fix the rear-stage internal gear 12B and the output shaft 14. For example, adhesive is applied to the cylindrical portion of the rear-stage internal gear 12B (the portion where the phasing portion 101 is not formed) shown in a gray rounded rectangle in Fig. 10A, and the opening 130 of the output shaft 14 and the cylindrical portion of the rear-stage internal gear 12B are bonded together.

[0062] In the example of Fig. 10B, adhesive is used to fix the main body portion 11 and the front-stage internal gear 12A. For example, adhesive is applied to the cylindrical portion of the front-stage internal gear 12A (the portion where the phasing portion 101 is not formed), which is shown surrounded by a gray rounded rectangle in Fig. 10B, and the opening 120 of the main body portion 11 and the cylindrical portion of the front-stage internal gear 12A are bonded together.

[0063] The means for fixing the internal gear 12 is preferably determined based on the torque capacity. Possible means for fixing the internal gear 12 include fixing with screws 151, fixing with an adhesive, or fixing with both screws 151 and an adhesive.

[0064] By completely fixing the internal gear 12 to the main body 11 and the output shaft 14, it is possible to improve the rigidity of the planetary reducer 1 and also to prevent backlash from occurring due to a gap between the phase determination portion on the main body 11 or output shaft 14 side and the phase determination portion on the internal gear 12 side.

[0065] 2. Modifications Example of forming four phase determining portions on an internal gear FIG. 11 is a diagram showing an example of a main body 11 and an output shaft 14 to which an internal gear 12 having four phase determining portions 101 is assembled.

[0066] Four phasing portions 101-1 to 101-4 are formed on the outer periphery of the cylindrical portion of the internal gear 12 in Fig. 11. The phasing portions 101-1 and 101-3 are formed at positions symmetrical with respect to the center of the internal gear 12, while the phasing portions 101-2 and 101-4 are formed at positions symmetrical with respect to the center of the internal gear 12. The phasing portions 101-1 to 101-4 have the same shape, and for example, a notch that functions as a marker is formed only in the phasing portion 101-1.

[0067] As shown in FIG. 11A, the main body 11 is formed with four phase determining portions 121-1 to 121-4 into which the phase determining portions 101 are fitted.

[0068] Four phasing portions 121-1 to 121-4 are formed on the edge of the opening 120. The phasing portions 121-1 and 121-3 are formed at positions symmetrical with respect to the center of the main body 11, and the phasing portions 121-2 and 121-4 are formed at positions symmetrical with respect to the center of the main body 11.

[0069] In A of Fig. 11, the circumferential widths of the phase determining portion 121-1 and the phase determining portion 121-3 are approximately the same as the circumferential width of the phase determining portion 101 on the front-stage internal gear 12A side, so the phase determining portion 101 is fitted with the phase determining portion 121-1 and the phase determining portion 121-3 with high precision. In the example of A of Fig. 11, the phase determining portion 101-1 is fitted with the phase determining portion 121-1, and the phase determining portion 101-3 is fitted with the phase determining portion 121-3.

[0070] On the other hand, the phase determining portion 121-2 is fitted with the phase determining portion 101-2, and the phase determining portion 121-4 is fitted with the phase determining portion 101-4. The circumferential widths of the phase determining portion 121-2 and the phase determining portion 121-4 are formed to be larger than the circumferential width of the phase determining portion 101 on the front-stage internal gear 12A side (the circumferential widths of the phase determining portions 121-1 and 121-3).

[0071] Therefore, gap G2 is larger than gap G1. Gap G1 is a gap that occurs between the phasing unit 101-1 and the phasing unit 121-1 in the circumferential direction, and between the phasing unit 101-3 and the phasing unit 121-3 in the circumferential direction. Gap G2 is a gap that occurs between the phasing unit 101-2 and the phasing unit 121-2 in the circumferential direction, and between the phasing unit 101-4 and the phasing unit 121-4 in the circumferential direction.

[0072] In this way, the main body 11 is formed with, for example, a combination of two phasing portions 121 (third phasing portions) whose circumferential width is formed so as to approximately match the circumferential width of the phasing portion 101 on the front-stage internal gear 12A side, and which are arranged at positions symmetrical about the center of the opening 120. The other phasing portion 121 (fourth phasing portion) is formed with a width greater than the width of the phasing portion 101 on the front-stage internal gear 12A side.

[0073] Furthermore, for example, when a number of phasing portions 121 that is a multiple of three are formed on the main body 11, a set of three phasing portions 121 is formed on the main body 11, each of which has a circumferential width that is approximately the same as the circumferential width of the phasing portion 101 on the front-stage internal gear 12A side and is arranged at equal intervals along the circumference of the opening 120. The other phasing portions 121 are formed so that their widths are larger than the width of the phasing portion 101 on the front-stage internal gear 12A side.

[0074] As shown in FIG. 11B, the output shaft 14 is formed with four phase determining portions 131-1 to 131-4 into which the phase determining portions 101 are fitted.

[0075] Four phasing portions 131-1 to 131-4 are formed on the edge of the opening 130. The phasing portions 131-1 and 131-3 are formed at positions symmetrical with respect to the center of the output shaft 14, and the phasing portions 131-2 and 131-4 are formed at positions symmetrical with respect to the center of the output shaft 14.

[0076] In B of Fig. 11, the circumferential widths of the phase determining portion 131-1 and the phase determining portion 131-3 are approximately the same as the circumferential width of the phase determining portion 101 on the rear-stage internal gear 12B side, so the phase determining portion 101 is fitted with the phase determining portion 131-1 and the phase determining portion 131-3 with high precision. In the example of B of Fig. 11, the phase determining portion 101-1 is fitted with the phase determining portion 131-1, and the phase determining portion 101-3 is fitted with the phase determining portion 131-3.

[0077] On the other hand, the phase determining portion 131-2 is fitted with the phase determining portion 101-2, and the phase determining portion 131-4 is fitted with the phase determining portion 101-4. The circumferential widths of the phase determining portion 131-2 and the phase determining portion 131-4 are formed to be larger than the circumferential width of the phase determining portion 101 on the rear-stage internal gear 12B side (the circumferential widths of the phase determining portions 131-1 and 131-3).

[0078] Therefore, gap G4 is larger than gap G3. Gap G3 is a gap that occurs between the phasing unit 101-1 and the phasing unit 131-1 in the circumferential direction, and between the phasing unit 101-3 and the phasing unit 131-3 in the circumferential direction. Gap G4 is a gap that occurs between the phasing unit 101-2 and the phasing unit 131-2 in the circumferential direction, and between the phasing unit 101-4 and the phasing unit 131-4 in the circumferential direction.

[0079] In this way, similar to the main body portion 11, the output shaft 14 is formed with, for example, a combination of two phasing portions 131 (third phasing portions) whose circumferential width is formed so as to approximately match the circumferential width of the phasing portion 101 on the rear-stage internal gear 12B side, and which are arranged at positions symmetrical about the center of the opening 130. The other phasing portion 131 (fourth phasing portion) is formed with a width greater than the width of the phasing portion 101 on the rear-stage internal gear 12B side.

[0080] Furthermore, for example, when a number of phasing portions 131 that is a multiple of three is formed on the output shaft 14, a set of three phasing portions 131 is formed on the output shaft 14, each set having a circumferential width that is approximately equal to the circumferential width of the phasing portion 101 on the rear-stage internal gear 12B side and that is equally spaced along the circumference of the opening 130. The other phasing portions 131 are formed so that their widths are larger than the widths of the phasing portions 101 on the rear-stage internal gear 12B side.

[0081] FIG. 12 is a diagram illustrating the orientation of the front-stage internal gear 12A to be assembled to the main body 11.

[0082] Even when four phase determining portions 101 are formed on the front-stage internal gear 12A, as shown in Figure 12, there are four possible phases (orientations) of the front-stage internal gear 12A when it is assembled to the main body 11, depending on which of the phase determining portions 121-1 to 121-4 on the main body 11 the phase determining portion 101-1 on the front-stage internal gear 12A is fitted to.

[0083] When four or more phasing portions 101 are formed on the internal gear 12, the internal gear 12 can be fixed to the main body 11 and the output shaft 14 by forming only some of the phasing portions 121 and 131 so that their widths approximately match the widths of the phasing portions 101. Since it is only necessary to form only some of the phasing portions 121 and 131 with high dimensional accuracy rather than forming all of the phasing portions 121 and 131 with high dimensional accuracy, it is possible to reduce the number of steps required to process the main body 11 and the output shaft 14.

[0084] Example of forming eight phase determining portions on the main body portion or the output shaft FIG. 13 is a diagram showing an example of the main body portion 11 having eight phase determining portions 121. In FIG.

[0085] Eight phasing portions 101-1 to 101-8 are formed on the outer periphery of the cylindrical portion of the internal gear 12 in Figure 13A. The phasing portions 101-1 and 101-5 are formed symmetrically about the center of the internal gear 12, while the phasing portions 101-2 and 101-6 are formed symmetrically about the center of the internal gear 12. The phasing portions 101-3 and 101-7 are formed symmetrically about the center of the internal gear 12, while the phasing portions 101-4 and 101-8 are formed symmetrically about the center of the internal gear 12. The phasing portions 101-1 to 101-8 have the same shape, and only the phasing portion 101-1 has a notch that functions as a marker.

[0086] As shown in FIG. 13A, the main body 11 is formed with eight phase determining portions 121-1 to 121-8 into which the phase determining portions 101 are fitted.

[0087] Eight phasing portions 121-1 to 121-8 are formed on the edge of the opening 120. The phasing portions 121-1 and 121-5 are formed at positions symmetrical with respect to the center of the main body 11, and the phasing portions 121-2 and 121-6 are formed at positions symmetrical with respect to the center of the main body 11. The phasing portions 121-3 and 121-7 are formed at positions symmetrical with respect to the center of the main body 11, and the phasing portions 121-4 and 121-8 are formed at positions symmetrical with respect to the center of the main body 11.

[0088] In A of Fig. 13, the circumferential widths of the phasing portion 121-1 and the phasing portion 121-5 are approximately the same as the circumferential width of the phasing portion 101 on the front-stage internal gear 12A side, so the phasing portion 101 is fitted with the phasing portion 121-1 and the phasing portion 121-5 with high precision. In the example of A of Fig. 13, the phasing portion 101-1 is fitted with the phasing portion 121-1, and the phasing portion 101-5 is fitted with the phasing portion 121-5.

[0089] On the other hand, the phasing portion 121-2 is fitted with the phasing portion 101-2, the phasing portion 121-3 is fitted with the phasing portion 101-3, and the phasing portion 121-4 is fitted with the phasing portion 101-4. The phasing portion 101-6 is fitted with the phasing portion 121-6, the phasing portion 101-7 is fitted with the phasing portion 101-7, and the phasing portion 121-8 is fitted with the phasing portion 101-8. The circumferential widths of the phasing portions 121-2 to 121-4 and the phasing portions 121-6 to 121-8 are formed larger than the circumferential width of the phasing portion 101 on the front-stage internal gear 12A side (the circumferential width of the phasing portions 121-1 and 121-5).

[0090] Two phasing portions 101-1 and 101-2 are formed on the outer periphery of the cylindrical portion of the internal gear 12 in Fig. 13B. The phasing portions 101-1 and 101-2 are formed at positions symmetrical with respect to the center of the internal gear 12. The phasing portions 101-1 and 101-2 have the same shape, and only the phasing portion 101-1 has a notch that functions as a marker.

[0091] In Fig. 13B, as in Fig. 13A, the main body 11 is formed with eight phasing portions 121-1 to 121-8 into which the phasing portions 101 are fitted. In Fig. 13B, the circumferential width of the phasing portions 121-1 to 121-8 approximately matches the circumferential width of the phasing portion 101 on the front-stage internal gear 12A side. Therefore, the phasing portions 101 and 121-1 to 121-8 are fitted with high precision. In the example of Fig. 13B, the phasing portion 101-1 is fitted into the phasing portion 121-1, and the phasing portion 101-2 is fitted into the phasing portion 121-5.

[0092] On the other hand, the phase determining units 121-2 to 121-4 and the phase determining units 121-6 to 121-8 are not fitted with the phase determining units 101.

[0093] When eight phase determining portions 121 are formed on the main body portion 11, there are eight possible phases that can be considered as the phase (orientation) of the front-stage internal gear 12A when assembled to the main body portion 11, depending on which of the phase determining portions 121-1 to 121-8 on the main body portion 11 the phase determining portion 101-1 on the front-stage internal gear 12A is fitted to.

[0094] Similarly to the main body portion 11, the output shaft 14 may also be formed with, for example, eight phase determining portions 131.

[0095] As described above, by increasing the number of phase determining portions 121 formed on the main body portion 11 or the output shaft 14, the phase of the internal gear 12 can be increased when assembled to the main body portion 11 or the output shaft 14, making it easier to absorb processing errors in gears, etc.

[0096] Example of Means for Forming Phase Determining Portion 101 on the Internal Gear 12 Side FIG. 14 is a diagram showing a modified example of the external appearance of the internal gear 12. In FIG.

[0097] 14, pin members are protruded from the outer periphery of the internal gear 12 to form phasing portions 201-1 and 201-2. The phasing portions 201-1 and 201-2 are formed symmetrically about the center of the internal gear 12. The phasing portions 201-1 and 201-2 are fitted into phasing portions on the main body 11 or output shaft 14 side. On the outer periphery of the internal gear 12, for example, near the phasing portion 201-1, a notch 202 is formed that functions as a mark for identifying the reference phasing portion 201-1.

[0098] By forming the phase determining portion by protruding a pin member rather than by cutting the outer periphery of the internal gear 12, it is possible to reduce the processing costs of the internal gear 12.

[0099] - Examples of shapes of phase determining portions In the above, examples have been described in which a convex portion as a phase determining portion is formed on the internal gear 12 and a concave portion as a phase determining portion is formed on the main body 11 or the output shaft 14, but a concave portion as a phase determining portion may also be formed on the internal gear 12.

[0100] FIG. 15 is a diagram showing an example of the internal gear 12 and the main body 11 when a recess is formed in the internal gear 12 as a phase determining portion.

[0101] Concave phasing portions 211-1 and 211-2 are formed on the outer periphery of the cylindrical portion of the front-stage internal gear 12A in FIG. 15A. The concave phasing portions 211-1 and 211-2 have a shape that matches the convex shape of the phasing portion provided on the main body 11. The phasing portions 211-1 and 211-2 are formed at positions symmetrical with respect to the center of the front-stage internal gear 12A. In other words, the phasing portions 211-1 and 211-2 are arranged at equal intervals along the outer periphery of the cylindrical portion of the front-stage internal gear 12A. On the outer periphery of the front-stage internal gear 12A, for example, near the phasing portion 211-1, a notch 212 is formed that functions as a marker for identifying the reference phasing portion 211-1.

[0102] Hereinafter, when there is no need to particularly distinguish between the phase determining units 211-1 and 211-2, they will be simply referred to as the phase determining unit 211.

[0103] 15B, two phase determining portions 221-1 and 221-2 are formed so as to protrude toward the center of the opening 120. The phase determining portions 221-1 and 221-2 are formed at positions symmetrical with respect to the center of the main body 11. In other words, the phase determining portions 221-1 and 221-2 are arranged at equal intervals along the circumference of the opening 120.

[0104] Hereinafter, when there is no need to particularly distinguish between the phase determining units 221-1 and 221-2, they will be simply referred to as the phase determining unit 221.

[0105] The circumferential width of the phase determining portion 221 is approximately the same as the circumferential width of the phase determining portion 211 on the front-stage internal gear 12A side, so that the phase determining portion 211 and the phase determining portion 221 are fitted together with high precision. In the example of C in Fig. 15, the phase determining portion 221-1 is fitted into the phase determining portion 211-1, and the phase determining portion 221-2 is fitted into the phase determining portion 211-2.

[0106] As in the case described with reference to FIG. 15, when a recessed portion is formed as a phase determining portion in the rear-stage internal gear 12B, a protruding portion is formed as a phase determining portion in the output shaft 14.

[0107] When a convex portion serving as a phasing portion is formed on the internal gear 12, for example, an internal gear having an outer diameter larger than the outer diameter of the final cylindrical portion of the internal gear 12 is prepared, and the outer surface of the cylindrical portion of the internal gear is ground or etched to form the phasing portion. On the other hand, when a concave portion is formed on the internal gear 12, for example, an internal gear having an outer diameter the same as the outer diameter of the final cylindrical portion of the internal gear 12 is prepared, and the outer surface of the internal gear is ground or etched to form the phasing portion.

[0108] In this way, when a recess is formed in the internal gear 12 as a phase determining portion, the outer diameter of the internal gear before the phase determining portion is formed can be reduced, thereby making it possible to reduce the processing costs of the internal gear 12.

[0109] On the other hand, whether a convex portion or a concave portion is formed as the phasing portion on the main body 11 or the output shaft 14, the opening and the phasing portion can be formed together, and therefore there is almost no difference in the processing costs of the main body 11 or the output shaft 14. Therefore, when a concave portion is formed as the phasing portion on the internal gear 12, it is expected that the manufacturing costs of the entire planetary reducer 1 will be reduced compared to when a convex portion is formed as the phasing portion.

[0110] The internal gear 12 may be formed with a phase determining portion that is partially concave and partially convex. In this case, the main body 11 and the output shaft 14 are formed with phase determining portions that are shaped to match the shape of the phase determining portion on the internal gear 12 side.

[0111] 3. Application Examples The planetary reducer 1 of the present technology can be applied to, for example, a robot.

[0112] FIG. 16 is a diagram showing a configuration example of a robot 301 to which the planetary reducer 1 of the present technology is applied.

[0113] As shown in FIG. 16, the robot 301 is made up of, for example, joint driving units 311-1 to 311-N, sensors 312-1 to 312-M, a communication unit 313, a camera 314, a recording unit 315, an environmental information acquisition unit 316, and a control unit 317.

[0114] In the following, when there is no need to particularly distinguish between the joint driving units 311-1 to 311-N, they will simply be referred to as joint driving units 311. In addition, in the following, when there is no need to particularly distinguish between the sensors 312-1 to 312-M, they will simply be referred to as sensors 312.

[0115] The joint driving units 311-1 to 311-N are configured with actuators and the like, and drive the joints of the robot 301 under the control of the control unit 317. The actuators include a planetary reducer 1 (FIG. 1), a motor, a brake, an encoder, a driver, a torque sensor, and the like.

[0116] When the joint drive unit 311 drives the joint unit including the joint drive unit 311, the link connected to the joint unit rotates or moves linearly in conjunction with the movement of the joint unit.

[0117] The robot 301 is only required to be provided with at least one joint (joint driving unit 311), and the number of joints may be any number.

[0118] In addition, the joint driving unit 311 measures one or more physical quantities related to the operation of the joint, such as the linear or rotational movement amount of the actuator when the joint is driven, the current consumption value of the actuator, the torque, force (translational force), and speed when the actuator is driven, and supplies the measurement results to the control unit 317.

[0119] Note that part or all of one or more physical quantities related to the movement of a joint may be measured by a sensor 312 provided adjacent to the joint.

[0120] The sensors 312-1 to 312-M are configured by torque sensors, force sensors, load cells, contact sensors, pressure distribution sensors, and the like.

[0121] The sensors 312-1 to 312-M measure physical quantities related to external forces applied directly or indirectly to each part of the robot 301, such as torque, load, pressure, and pressure distribution, and supply the measurement results to the control unit 317.

[0122] For example, the M sensors 312 include sensors 312 that measure physical quantities related to external forces indirectly applied to joints, and sensors 312 that measure physical quantities related to external forces directly applied to parts other than the joints.

[0123] For example, a sensor 312 provided adjacent to a joint (joint driving unit 311) is applied to a part such as a link connected to the joint, i.e., a part other than the joint (a part different from the joint), and measures the torque of an external force transmitted to the joint through that part, and supplies the measurement results to a control unit 317.

[0124] In addition, for example, a sensor 312 provided adjacent to a part other than a joint (a part different from a joint) measures pressure due to an external force applied directly to that part, and supplies the measurement results to the control unit 317.

[0125] The communication unit 313 communicates with an external device, for example, wirelessly.

[0126] The camera 314 captures the surroundings of the robot 301 as a subject, and supplies the resulting image to the control unit 317 .

[0127] The recording unit 315 records various data supplied from the control unit 317 and supplies the recorded data to the control unit 317 .

[0128] The environmental information acquisition unit 316 consists of a thermometer, hygrometer, concentration meter, etc., and measures information about the environment around the robot 301, such as the temperature and humidity, particle concentration, and radiation concentration around the robot 301, and supplies environmental information indicating the measurement results to the control unit 317.

[0129] The control unit 317 controls the overall operation of the robot 301 .

[0130] The effects described in this specification are merely examples and are not limiting, and other effects may also be present.

[0131] The embodiments of the present technology are not limited to the above-described embodiments, and various modifications are possible without departing from the spirit of the present technology.

[0132] <Examples of Combinations of Configurations> The present technology can also have the following configurations.

[0133] (1) A reducer comprising: a sun gear; a plurality of planetary gears meshing with the sun gear and the internal gear; the internal gear having first phasing portions formed thereon that fix the phase of the internal gear; and a support portion having a plurality of second phasing portions formed thereon that fit with the first phasing portions. (2) The reducer described in (1) above, in which a plurality of first phasing portions are formed on the internal gear, and the support portion has a number of second phasing portions equal to or greater than the number of first phasing portions. (3) The reducer described in (2) above, in which the plurality of first phasing portions are arranged at equal intervals along the outer periphery of the cylindrical portion of the internal gear. (4) The reducer described in (2) or (3) above, in which the internal gear has a mark formed thereon to identify at least one of the plurality of first phasing portions. (5) The reducer according to any one of (1) to (4), wherein the support portion further has an opening into which the cylindrical portion of the internal gear fits, and the plurality of second phasing portions are formed along the circumference of the opening. (6) The reducer according to (5), wherein the plurality of second phasing portions include a third phasing portion formed so that its circumferential width is approximately the same as that of the first phasing portion, and a fourth phasing portion formed so that its circumferential width is greater than that of the third phasing portion. (7) The reducer according to (6), wherein the plurality of second phasing portions are arranged at equal intervals along the circumference of the opening. (8) The reducer according to (7), wherein the plurality of second phasing portions include a plurality of third phasing portions arranged at equal intervals along the circumference of the opening. (9) The reducer according to any one of (1) to (8), wherein the internal gear is fixed to the support portion with at least one of screws and an adhesive. (10) The reducer according to any one of (1) to (9), wherein the first phase determining portion has a convex shape, and the second phase determining portion has a concave shape. (11) The reducer according to (10), wherein the first phase determining portion is formed by a pin member protruding from an outer periphery of a cylindrical portion of the internal gear.(12) The reducer according to any one of (1) to (9), wherein the first phase determining portion has a concave shape, and the second phase determining portion has a convex shape. (13) The reducer according to any one of (1) to (12), wherein the plurality of planetary gears are each formed by integrally forming a front-stage planetary gear and a rear-stage planetary gear, and comprises: the front-stage internal gear meshing with the plurality of front-stage planetary gears, the rear-stage internal gear meshing with the plurality of rear-stage planetary gears, the front-stage support portion formed with the second phase determining portion that fits with the first phase determining portion formed on the front-stage internal gear, and the rear-stage support portion formed with the second phase determining portion that fits with the first phase determining portion formed on the rear-stage internal gear. (14) The reducer according to (13), wherein the rear-stage support portion includes an output shaft. (15) A robot having a reducer including: a sun gear; a plurality of planetary gears meshing with the sun gear and the internal gear; the internal gear having a first phase determining portion formed thereon that fixes the phase of the internal gear; and a support portion having a plurality of second phase determining portions formed thereon that fit into the first phase determining portions.

[0134] DESCRIPTION OF SYMBOLS 1 Planetary reducer, 11 Main body, 12A Front stage internal gear, 12B Rear stage internal gear, 13 Carrier, 14 Output shaft, 15 Cross roller unit, 31 Input shaft, 32 Sun gear, 33-1 Planet gear, 33-1A Front stage planetary gear, 33-1B Rear stage planetary gear, 33-2 Planet gear, 33-2A Front stage planetary gear, 33-2B Rear stage planetary gear, 51 Carrier, 61 Input shaft, 62 Sun gear, 63-1 Planet gear, 63-1A Front stage planetary gear, 63-1B Rear stage planetary gear, 81 Input shaft, 82 Sun gear, 83-1 to 83-3 Planet gears, 84 Internal gear, 85 Planet carrier, 86 Output shaft 101 Phase determining portion, 102 Notch, 121, 131 Phase determining portion, 151 Screw, 201 Phase determining portion, 202 Notch, 211 Phase determining portion, 212 Notch, 221 Phase determining portion

Claims

1. A reducer comprising: a sun gear; a plurality of planetary gears meshing with the sun gear and an internal gear; the internal gear having a first phase determining portion formed thereon that fixes the phase of the internal gear; and a support portion having a plurality of second phase determining portions that fit into the first phase determining portions.

2. The reducer according to claim 1, wherein a plurality of first phasing portions are formed on the internal gear, and a number of second phasing portions equal to or greater than the number of first phasing portions are formed on the support portion.

3. The reducer according to claim 2, wherein the plurality of first phase determining portions are arranged at equal intervals along the outer periphery of the cylindrical portion of the internal gear.

4. The reducer according to claim 2, wherein the internal gear is formed with a mark for identifying at least one of the plurality of first phase determining portions.

5. The reducer according to claim 1, wherein the support portion is further formed with an opening into which the cylindrical portion of the internal gear is fitted, and the plurality of second phase determining portions are formed along the circumference of the opening.

6. A reducer as described in claim 5, wherein the plurality of second phasing portions include a third phasing portion formed so that its circumferential width is approximately the same as the circumferential width of the first phasing portion, and a fourth phasing portion formed so that its circumferential width is greater than the circumferential width of the third phasing portion.

7. The reducer according to claim 6, wherein the plurality of second phase determining portions are arranged at equal intervals along the circumference of the opening.

8. The reducer according to claim 7, wherein the plurality of second phasing portions include a plurality of third phasing portions arranged at equal intervals along the circumference of the opening.

9. The reducer according to claim 1, wherein the internal gear is fixed to the support portion by at least one of a screw and an adhesive.

10. The reducer according to claim 1, wherein the first phase determining portion has a convex shape, and the second phase determining portion has a concave shape.

11. The reducer according to claim 10, wherein the first phase determining portion is formed by a pin member protruding from the outer periphery of the cylindrical portion of the internal gear.

12. The reducer according to claim 1, wherein the first phase determining portion has a concave shape, and the second phase determining portion has a convex shape.

13. A reducer as described in claim 1, wherein each of the plurality of planetary gears is formed by integrating a front-stage planetary gear and a rear-stage planetary gear, and comprises: a front-stage internal gear that meshes with the plurality of front-stage planetary gears; a rear-stage internal gear that meshes with the plurality of rear-stage planetary gears; a front-stage support portion formed with the second phase determining portion that fits into the first phase determining portion formed on the front-stage internal gear; and a rear-stage support portion formed with the second phase determining portion that fits into the first phase determining portion formed on the rear-stage internal gear.

14. The reducer according to claim 13, wherein the rear support portion includes an output shaft.

15. A robot having a reducer comprising: a sun gear; a plurality of planetary gears meshing with the sun gear and an internal gear; the internal gear having a first phase determining portion formed thereon that fixes the phase of the internal gear; and a support portion having a plurality of second phase determining portions formed thereon that fit into the first phase determining portion.

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