WO2024139408A1 - Internal meshing planetary gear device and joint device for robot - Google Patents

Internal meshing planetary gear device and joint device for robot Download PDF

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Publication number
WO2024139408A1
WO2024139408A1 PCT/CN2023/118372 CN2023118372W WO2024139408A1 WO 2024139408 A1 WO2024139408 A1 WO 2024139408A1 CN 2023118372 W CN2023118372 W CN 2023118372W WO 2024139408 A1 WO2024139408 A1 WO 2024139408A1
Authority
WO
WIPO (PCT)
Prior art keywords
planetary gear
gear
internal
teeth
rotation axis
Prior art date
Application number
PCT/CN2023/118372
Other languages
French (fr)
Chinese (zh)
Inventor
田中雅之
吴达祺
Original Assignee
美的集团股份有限公司
广东美的电气有限公司
广东极亚精机科技有限公司
广东美的制冷设备有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 美的集团股份有限公司, 广东美的电气有限公司, 广东极亚精机科技有限公司, 广东美的制冷设备有限公司 filed Critical 美的集团股份有限公司
Publication of WO2024139408A1 publication Critical patent/WO2024139408A1/en

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25J—MANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES
    • B25J17/00—Joints
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16H—GEARING
    • F16H1/00—Toothed gearings for conveying rotary motion
    • F16H1/28—Toothed gearings for conveying rotary motion with gears having orbital motion
    • F16H1/32—Toothed gearings for conveying rotary motion with gears having orbital motion in which the central axis of the gearing lies inside the periphery of an orbital gear
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16H—GEARING
    • F16H55/00—Elements with teeth or friction surfaces for conveying motion; Worms, pulleys or sheaves for gearing mechanisms
    • F16H55/02—Toothed members; Worms
    • F16H55/14—Construction providing resilience or vibration-damping
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16H—GEARING
    • F16H55/00—Elements with teeth or friction surfaces for conveying motion; Worms, pulleys or sheaves for gearing mechanisms
    • F16H55/02—Toothed members; Worms
    • F16H55/17—Toothed wheels
    • F16H55/18—Special devices for taking up backlash
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16H—GEARING
    • F16H57/00—General details of gearing
    • F16H57/02—Gearboxes; Mounting gearing therein
    • F16H57/021—Shaft support structures, e.g. partition walls, bearing eyes, casing walls or covers with bearings
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16H—GEARING
    • F16H57/00—General details of gearing
    • F16H57/02—Gearboxes; Mounting gearing therein
    • F16H57/023—Mounting or installation of gears or shafts in the gearboxes, e.g. methods or means for assembly
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16H—GEARING
    • F16H57/00—General details of gearing
    • F16H57/04—Features relating to lubrication or cooling or heating
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K7/00—Arrangements for handling mechanical energy structurally associated with dynamo-electric machines, e.g. structural association with mechanical driving motors or auxiliary dynamo-electric machines
    • H02K7/10—Structural association with clutches, brakes, gears, pulleys or mechanical starters
    • H02K7/116—Structural association with clutches, brakes, gears, pulleys or mechanical starters with gears

Definitions

  • FIG. 12A shows a main part of an internally meshing planetary gear device according to a modified example, and is a schematic enlarged view corresponding to the area Z1 of FIG. 7 .
  • FIG. 13 shows a main part of the internally meshing planetary gear device according to the second embodiment, and is a schematic enlarged view corresponding to the area Z1 of FIG. 7 .
  • crankshaft gears 502A, 502B, 502C are arranged in a manner meshing with the input gear 501. Therefore, when the input shaft 500 is driven, the gear device 1 drives the crankshafts 7A, 7B, 7C synchronously by using the input gear 501, thereby causing the planetary gear 3 to oscillate.
  • the gear device 1 when the gear device 1 is used in the actuator 100, by applying a rotational force as an input to the input shaft 500, a rotational force as an output is taken out from the pair of brackets 18 and 19 integrated with the inner ring 61 of the bearing member 6.
  • the gear device 1 uses the rotation of the input shaft 500 as an input rotation and the rotation of the pair of brackets 18 and 19 integrated with the inner ring 61 as an output rotation.
  • an output rotation which is reduced in speed at a relatively high reduction ratio with respect to the input rotation can be obtained.
  • the driving source 101 is a power generating source such as an electric motor.
  • the power generated by the driving source 101 is transmitted to the input shaft 500 in the gear device 1.
  • the driving source 101 is connected to the input shaft 500, and the power generated by the driving source 101 is transmitted to the input shaft 500.
  • the driving source 101 can rotate the input shaft 500.
  • the plurality of inner circumferential grooves 223 are all parallel to the rotation axis Ax1 and are formed over the entire length in the thickness direction of the gear body 22.
  • the plurality of pins 23 are combined with the gear body 22 in a manner of being embedded in the plurality of inner circumferential grooves 223.
  • the plurality of pins 23 are each held
  • the gear body 22 is in a state of being able to rotate in the inner peripheral groove 223.
  • the gear body 22 (together with the outer ring 62) is fixed to the housing 10. Furthermore, the gear body 22 is formed with a plurality of fixing holes 222 for fixing (see FIG. 5 ).
  • These two planetary gears 3 are arranged with a phase difference of 180 degrees around the rotation axis Ax1.
  • the center (the center of the pitch circle of the external teeth 31) C1 of the first planetary gear 301 located on the input side (right side of FIG. 4) of the rotation axis Ax1 is in a state of being deviated (offset) upward in the figure relative to the rotation axis Ax1.
  • the rotation axis Ax1 is in a state of being deviated (offset) downward in the figure relative to the rotation axis Ax1.
  • the distance ⁇ L1 between the rotation axis Ax1 and the center C1 is the eccentricity of the first planetary gear 301 relative to the rotation axis Ax1
  • the distance ⁇ L2 between the rotation axis Ax1 and the center C2 is the eccentricity of the second planetary gear 302 relative to the rotation axis Ax1.
  • the plurality of planetary gears 3 are evenly arranged in the circumferential direction around the rotation axis Ax1 , thereby achieving a balance between the weight and the load among the plurality of planetary gears 3 .
  • the centers C1 and C2 of the first planetary gear 301 and the second planetary gear 302 are 180 degrees rotationally symmetrical with respect to the rotation axis Ax1.
  • the eccentricity ⁇ L1 and the eccentricity ⁇ L2 have opposite directions when viewed from the rotation axis Ax1, but have the same absolute values.
  • each crankshaft 7A, 7B, 7C has two eccentric portions 72 with respect to one axial portion 71.
  • the eccentricity ⁇ L0 (see FIGS. 5 and 6 ) of the center C0 of the two eccentric portions 72 from the center (axial center Ax2) of the axial portion 71 is the same as the eccentricity ⁇ L1 and ⁇ L2 of the first planetary gear 301 and the second planetary gear 302 with respect to the rotation axis Ax1, respectively.
  • the shapes of the plurality of crankshafts 7A, 7B, 7C are the same.
  • the shapes of the plurality of crankshaft gears 502A, 502B, 502C are the same.
  • a pair of brackets 18 and 19 are arranged on both sides of the first planetary gear 301 and the second planetary gear 302 in the direction parallel to the rotation axis Ax1 (axial direction).
  • the bracket 18 located on the input side (right side in FIG. 4) of the rotation axis Ax1 is referred to as the "input side bracket 18”
  • the bracket 19 located on the output side (left side in FIG. 4) of the rotation axis Ax1 is referred to as the "output side bracket 19".
  • Both ends of each crankshaft 7A, 7B, 7C are held by the pair of brackets 18 and 19 via rolling bearings 41 and 42.
  • the eccentric body bearing 5 is mounted on the eccentric portion 72 of each crankshaft 7A, 7B, 7C.
  • Three openings 33 corresponding to the three crankshafts 7A, 7B, 7C are formed in the first planetary gear 301 and the second planetary gear 302, respectively.
  • the eccentric body bearing 5 is accommodated in each opening 33.
  • the eccentric body bearing 5 is mounted on the first planetary gear 301 and the second planetary gear 302, respectively, and the crankshafts 7A, 7B, 7C are inserted into the eccentric body bearing 5, thereby combining the eccentric body bearing 5 and the crankshafts 7A, 7B, 7C with the planetary gear 3.
  • crankshafts 7A, 7B, and 7C are spline-connected to the crankshaft gears 502A, 502B, and 502C, so the three crankshafts 7A, 7B, and 7C rotate in the same direction at the same rotation speed in a state where the gear ratio between the input gear 501 and the crankshaft gears 502A, 502B, and 502C is reduced.
  • the three eccentric portions 72 formed at the same position on the input side of the rotation axis Ax1 in the three crankshafts 7A, 7B, and 7C rotate synchronously, causing the first planetary gear 301 to oscillate.
  • the three eccentric portions 72 formed at the same position on the output side of the rotation axis Ax1 in the three crankshafts 7A, 7B, and 7C rotate synchronously, causing the second planetary gear 302 to oscillate.
  • the planetary gears 3 (first planetary gears 301 and second planetary gears 302) thus configured are arranged on the inner side of the internal gear 2.
  • the planetary gears 3 are formed to be one size smaller than the internal gear 2, and the planetary gears 3 can swing on the inner side of the internal gear 2 when combined with the internal gear 2.
  • the outer teeth 31 are formed on the outer peripheral surface of the planetary gears 3, and the inner teeth 21 are formed on the inner peripheral surface of the internal gear 2. Therefore, when the planetary gears 3 are arranged on the inner side of the internal gear 2, the outer teeth 31 and the inner teeth 21 are opposite to each other.
  • the pitch circle of the external teeth 31 is one circle smaller than the pitch circle of the internal teeth 21.
  • the center C1 of the pitch circle of the external teeth 31 of the first planetary gear 301 is located at a position that is offset by a distance ⁇ L1 from the center (rotation axis Ax1) of the pitch circle of the internal teeth 21.
  • the center C2 of the pitch circle of the external teeth 31 of the second planetary gear 302 is offset by a distance ⁇ L2 from the center of the pitch circle of the internal teeth 21 (rotation axis Ax1 ).
  • the external teeth 31 and at least a part of the internal teeth 21 are opposite to each other with a gap therebetween, and if the difference in the number of teeth between the external teeth 31 and the internal teeth 21 is "2" or more, the entirety of the circumferential direction will not mesh with each other.
  • the planetary gear 3 swings (revolves) around the rotation axis Ax1 inside the internal gear 2, so the external teeth 31 and the internal teeth 21 are partially meshed.
  • the number of teeth of the internal teeth 21 in the internal gear 2 is N (N is a positive integer) greater than the number of teeth of the external teeth 31 of the planetary gear 3.
  • N is "2”
  • the number of teeth (of the external teeth 31) of the planetary gear 3 is "2" less than the number of teeth (of the internal teeth 21) of the internal gear 2.
  • the thickness of the first planetary gear 301 and the second planetary gear 302 combined is smaller than the thickness of the gear body 22 in the internal gear 2.
  • the dimension of the tooth direction (direction parallel to the rotation axis Ax1) of the external teeth 31 combined with the first planetary gear 301 and the second planetary gear 302 is smaller than the dimension of the tooth direction (direction parallel to the rotation axis Ax1) of the internal teeth 21.
  • the external teeth 31 of the first planetary gear 301 and the second planetary gear 302 are within the range of the tooth direction of the internal teeth 21.
  • first planetary gear 301 and the second planetary gear 302 are respectively meshed with the internal gear 2. Therefore, every time the first planetary gear 301 and the second planetary gear 302 swing, the first planetary gear 301 and the second planetary gear 302 produce a circumferential phase deviation of the difference in the number of teeth (internal teeth 21 and external teeth 31) relative to the internal gear 2, and rotate.
  • This rotation is transmitted to the pair of brackets 18 and 19 as a reciprocal rotation around the axis (rotation axis Ax1) of the internal gear 2 of each crankshaft 7A, 7B, 7C.
  • the pair of brackets 18 and 19 can be centered on the rotation axis Ax1 relative to the gear body (the housing 10 integrated with the gear body). Relative rotation.
  • the gear device 1 of this basic structure causes the planetary gear 3 to oscillate by means of a plurality of crankshafts 7A, 7B, and 7C disposed at positions offset from the rotation axis Ax1, and obtains a rotation output by utilizing the oscillation of the planetary gear 3. That is, in the gear device 1, when the planetary gear 3 oscillates and the meshing position of the internal teeth 21 and the external teeth 31 moves along the circumferential direction of the internal gear 2, a 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 (the internal gear 2 and the planetary gear 3).
  • the planetary gear 3 rotates (rotates) along with the relative rotation of the two gears.
  • a rotation output that is reduced in speed at a relatively high reduction ratio corresponding to the difference in the number of teeth between the two gears can be obtained from the planetary gear 3.
  • the bearing member 6 is a component having an outer ring 62 and an inner ring 61 and used to extract the output of the gear device 1 as the rotation of the inner ring 61 relative to the outer ring 62.
  • the bearing member 6 has a plurality of rolling elements 63 (see FIG. 4 ) in addition to the outer ring 62 and the inner ring 61.
  • the outer ring 62 and the inner ring 61 are both annular components.
  • the outer ring 62 and the inner ring 61 both have an annular shape that is a perfect circle when viewed from above.
  • the inner ring 61 is one circle smaller than the outer ring 62 and is arranged on the inner side of the outer ring 62.
  • the inner diameter of the outer ring 62 is larger than the outer diameter of the inner ring 61, so 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 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 in parallel along the circumferential direction of the outer ring 62.
  • the plurality of rolling elements 63 are all metal parts of the same shape and are arranged at equal intervals over the entire circumferential area of the outer ring 62.
  • the bearing member 6 is configured by the first bearing member 601 and the second bearing member 602 to withstand radial loads, loads in the thrust direction (along the direction of the rotation axis Ax1), and bending forces (bending moment loads) with respect to the rotation axis Ax1.
  • the first bearing member 601 and the second bearing member 602 are disposed on both sides of the planetary gear 3 in a direction parallel to the rotation axis Ax1 (axial direction) so as to be mutually spaced in a direction parallel to the rotation axis Ax1.
  • the bearing component 6 is a "combined angular ball bearing” that combines multiple (here, 2) angular ball bearings.
  • the first bearing component 601 and the second bearing component 602 are "back-to-back combination type" that bear the load in the thrust direction (along the direction of the rotation axis Ax1) in which the respective inner rings 61 approach each other.
  • the first bearing component 601 and the second bearing component 602 are combined in a state where appropriate preload is applied to the inner ring 61 by tightening the respective inner rings 61 in the direction in which they approach each other.
  • the output side bracket 19 has a plurality of (three as an example) bracket pins 191 (see FIG. 2 ) protruding from one surface of the output side bracket 19 toward the input side of the rotation axis Ax1.
  • These plurality of bracket pins 191 respectively penetrate a plurality of (three as an example) bracket holes 34 formed in the planetary gear 3, and the front ends of the plurality of bracket pins 191 are fixed to the input side bracket 18 by bracket bolts 192 (see FIG. 7 ).
  • a gap is ensured between the bracket pin 191 and the inner circumferential surface of the bracket hole 34, and the bracket pin 191 can move in the bracket hole 34, that is, can move relatively to the center of the bracket hole 34.
  • the bracket pin 191 does not contact the inner circumferential surface of the bracket hole 34.
  • the gear device 1 is used in the following manner: the rotation of the planetary gear 3 corresponding to the self-rotation component is extracted as the rotation of the input side bracket 18 and the output side bracket 19 integrated with the inner ring 61 of the bearing member 6. That is, in this basic structure, the relative rotation between the planetary gear 3 and the internal gear 2 is extracted from the input side bracket 18 and the output side bracket 19.
  • the gear device 1 is fixed to the housing 10 as a fixed member by the outer ring 62 of the bearing member 6 (see FIG. 4).
  • the end face of the input side (right side in FIG. 4 ) of the rotation axis Ax1 of the housing 10 is blocked by the input side bracket 18, and the end face of the output side (left side in FIG. 4 ) of the rotation axis Ax1 of the housing 10 is blocked by the output side bracket 19. Therefore, as shown in FIG. 4 , in the space surrounded by the housing 10, the input side bracket 18, and the output side bracket 19, the planetary gears 3 (the first planetary gear 301 and the second planetary gear 302), a plurality of pins 23, and the eccentric body bearing 5 are accommodated.
  • the plurality of (three in the basic structure) crankshafts 7A, 7B, and 7C each have an axial portion 71 and two eccentric portions 72.
  • the axial portion 71 has a cylindrical shape in which at least the outer peripheral surface is a perfect circle when viewed from above.
  • the axial center Ax2, which is the center of the axial portion 71, is parallel to the rotation axis Ax1.
  • the axial centers Ax2 of the plurality of crankshafts 7A, 7B, and 7C are arranged at equal intervals in the circumferential direction on a virtual circle centered on the rotation axis Ax1.
  • Each eccentric portion 72 It has a disc shape whose at least outer peripheral surface is a perfect circle when viewed from clothing.
  • the axial center portion 71 and the two eccentric portions 72 are integrally formed by one metal member, thereby realizing a seamless crankshaft 7A, 7B, 7C.
  • the crankshaft 7A, 7B, 7C of such a shape is combined with the eccentric body bearing 5 to the planetary gear 3. Therefore, in a state where the planetary gear 3 is combined with the eccentric body bearing 5 and the crankshaft 7A, 7B, 7C, when the crankshaft 7A, 7B, 7C rotates, the planetary gear 3 swings around the rotation axis Ax1.
  • a rotational force is applied as an input to the input shaft 500.
  • the input shaft 500 rotates around the rotation axis Ax1, and the planetary gear 3 swings (revolves) around the rotation axis Ax1.
  • the planetary gear 3 swings in a state where it is inscribed in the inner side of the internal gear 2 and a part of the external teeth 31 meshes with a part of the internal teeth 21, so the meshing position of the internal teeth 21 and the external teeth 31 moves along the circumferential direction of the internal gear 2.
  • a 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 (the internal gear 2 and the planetary gear 3).
  • the rotation (autorotation component) of the planetary gear 3 in addition to the swing component (revolution component) of the planetary gear 3 is transmitted to the pair of carriers 18 and 19 through the plurality of crankshafts 7A, 7B, and 7C.
  • a rotation output that is reduced at a relatively high reduction ratio corresponding to the difference in the number of teeth between the two gears is obtained from the pair of carriers 18 and 19.
  • the number of teeth V1 of the internal gear 2 is "72”
  • the number of teeth V2 of the planetary gear 3 is "70”
  • the difference in the number of teeth (V1-V2) is "2”
  • the reduction ratio R1 is "35”.
  • crankshaft 7A, 7B, 7C rotates clockwise around the axis Ax2 of the axial core 71 (refer to Figures 5 and 6) for one circle (360 degrees) when viewed from the input side of the rotation axis Ax1, the pair of brackets 18 and 19 rotate counterclockwise around the rotation axis Ax1 by the difference in the number of teeth "2" (that is, about 10.3 degrees).
  • such a high reduction ratio R1 can be achieved by the combination of the internal gear 2 and the planetary gear 3. Furthermore, between the input gear 501 and the plurality of crankshaft gears 502A, 502B, 502C, an appropriate reduction ratio can also be achieved according to the number of teeth of the input gear 501 and the crankshaft gears 502A, 502B, 502C. As a result, the gear device 1 as a whole can achieve a high reduction ratio.
  • the gear device 1 only needs to include at least the internal gear 2, the planetary gears 3, the crankshafts 7A, 7B, 7C and a pair of brackets 18, 19, and may further include a spacer 11 as shown in FIG. 4.
  • the spacer 11 is arranged between the pair of planetary gears 3 (first planetary gears 3) in a direction parallel to the rotation axis Ax1 (axial direction). gear 301 and the second planetary gear 302).
  • the output side cover 14 is formed in a disk shape with the rotation axis Ax1 as the center.
  • at least the outer peripheral surface of the output side cover 14 is a perfect circle with the rotation axis Ax1 as the center when viewed from above (viewed from one side in the axial direction).
  • the outer diameter of the output side cover 14 is one circle smaller than the outer diameter of the output side bracket 19.
  • the output side cover 14 is mounted relative to the output side bracket 19 from the outside, that is, on the side opposite to the planetary gear 3 when viewed from the output side bracket 19 (the left side in FIG. 7).
  • a pair of covers 13 and 14 are detachably mounted on a pair of brackets 18 and 19. That is, the input side cover 13 is detachably mounted on the input side bracket 18, and the output side cover 14 is detachably mounted on the output side bracket 19.
  • each cover 13 and 14 is mounted on each bracket 18 and 19 by a plurality of fixing bolts 142 (see FIG. 7). Therefore, by removing the plurality of fixing bolts 142, each cover 13 and 14 can be removed from each bracket 18 and 19.
  • the robot joint device 200 constructed in this way functions as a joint device by relatively rotating the first member 201 and the second member 202 around the rotation axis Ax1.
  • the input shaft 500 of the gear device 1A is driven by the drive source 101, so that the first member 201 and the second member 202 are relatively rotated.
  • the rotation (input rotation) generated by the driving source 101 is decelerated at a relatively high reduction ratio in the gear device 1A, and the first member 201 or the second member 202 is driven with a relatively high torque.
  • the first member 201 and the second member 202 connected by the gear device 1A can bend and stretch around the rotation axis Ax1.
  • the robot joint device 200 is used for a robot such as a horizontal multi-joint robot (articular robot). Furthermore, the robot joint device 200 is not limited to a horizontal multi-joint robot, and for example, it can also be used for an industrial robot other than a horizontal multi-joint robot, or a robot other than industrial robots.
  • the gear device 1A of this embodiment is not limited to the robot joint device 200, and for example, as a wheel device such as a hub motor, it can also be used in vehicles such as unmanned guided vehicles (AGV: Automated Guided Vehicle).
  • Implementation method 1 is only one of various implementation methods of the present disclosure. Implementation method 1 can be modified in various ways according to the design, etc., as long as it can achieve the purpose of the present disclosure.
  • the drawings referred to in the present disclosure are all schematic diagrams, and the size and thickness ratios of the various structural elements in the drawings are not necessarily limited to reflect the actual dimensional ratios.
  • each component of the gear device 1A is not limited to metal, and may be, for example, resin such as process plastic.
  • the end face of the output side of the rotating axis Ax1 of the crankshaft 7A, 7B, 7C is in direct contact with the output side cover 14, but it is not limited to this structure, and a plate-like component such as a gasket member may be arranged between the end face and the output side cover 14.
  • a plate-like component such as a gasket member
  • the gap between the end face and the output side cover 14 can be adjusted in the axial direction, and the "play" in the axial direction of the crankshaft 7A, 7B, 7C can be adjusted.
  • the plate-like component functions as a track ring (track disk) that reduces the friction between the end face and the output side cover 14.
  • the elastic deformation portion 24 is not limited to the diaphragm structure, and may be an appropriate structure including, for example, a cantilever structure or a leaf spring structure.
  • the detection unit 91 may be arranged on the surface (outer peripheral surface) of the elastic deformation portion 24, or at least a portion thereof may be buried in the elastic deformation portion 24. In addition, it is sufficient to provide at least one detection unit 91, or a plurality of detection units 91 may be provided.
  • the information processing unit 92 inputs the detection value (electrical signal) of the detection unit 91 and performs appropriate processing on the detection value.
  • the information processing unit 92 is mainly structured as a computer system having one or more processors, and executes programs through one or more processors to realize the function of the information processing unit 92.
  • the information processing unit 92 is mainly structured as a computer system having one or more processors such as a CPU (Central Processing Unit) and one or more memories such as a ROM (Read Only Memory) and a RAM (Random Access Memory), and performs various processes (information processing).
  • the information processing unit 92 for example, the information processing unit 92 is used to control the drive source 101 (refer to Figure 11).
  • the information processing unit 92 performs a torque estimation process for estimating the torque applied between the internal gear 2 and the planetary gear 3, for example, based on the detection value of the detection unit 91 corresponding to the deformation amount of the elastic deformation unit 24. That is, the information processing unit 92 estimates that the torque is larger as the deformation amount of the elastic deformation unit 24 is larger.
  • the information processing unit 92 reflects the torque estimated in this way, for example, in the control of the drive source 101.
  • the gear device 1B of this embodiment further includes a detection device for detecting the elastic deformation portion 24.
  • Deformation amount detection unit 91 According to this configuration, for example, the torque of the gear device 1B can be estimated based on the deformation amount of the elastic deformation unit 24. Therefore, the deformation amount of the elastic deformation unit 24 can be reflected in the control of the drive source 101, for example.
  • the information processing unit 92 may perform, for example, a wear detection process of the external teeth 31 in addition to or instead of the torque estimation process.
  • the first form of the internally meshing planetary gear device (1, 1A, 1B) includes an internal gear (2) and a planetary gear (3), and the planetary gear (3) is caused to rotate relative to the internal gear (2) by swinging the planetary gear (3).
  • the internal gear (2) has: an annular gear body (22); and a plurality of pins (23) that are held in a plurality of inner peripheral grooves (223) formed on the inner peripheral surface (221) of the gear body (22) in a state capable of self-rotation, and constitute the internal teeth (21).
  • the planetary gear (3) has external teeth (31) that partially mesh with the internal teeth (21).
  • the gear body (22) has an elastically deformable elastic portion (24) that can be elastically deformed at least at a portion where the plurality of inner peripheral grooves (223) are formed.
  • the pins (23) held in the inner peripheral grooves (223) are pressed against the outer teeth (31) by the elastic force of the elastic deformation portion (24) of the gear body (22). Therefore, the gap (play) between the inner teeth (21) and the outer teeth (31) formed by the plurality of pins (23) is filled, thereby reducing the backlash.
  • the gap between the inner teeth (21) and the outer teeth (31) at the meshing portion of the inner teeth (21) and the outer teeth (31) is expanded, and the increase of the backlash is also easily suppressed.
  • an elastic deformation portion (24) includes a portion where an outer peripheral groove (25) is formed in the circumferential direction on the outer peripheral surface of a gear body (22) and the wall is thinned.
  • an elastic deformation portion (24) is formed in the central portion of the tooth direction of the internal teeth (21) in the gear body (22), and the elastic deformation portion (24) is thinner than at least the two side portions of the tooth direction of the internal teeth 21 in the gear body 22, that is, the thickness is set to be smaller.
  • the inner diameter (r2) of each of the plurality of inner circumferential grooves (223) is larger than the outer diameter (r1) of each of the plurality of pins (23).
  • the inner diameter of the inner circumferential groove (223) is unlikely to be lower than the outer diameter of the pin (23), and the opening edge of the inner circumferential groove (223) can be prevented from biting into the outer surface of the pin (23).
  • a fourth aspect of the internally meshing planetary gear device (1, 1A, 1B) is based on any one of the first to third aspects and further includes a detection unit (91) for detecting the amount of deformation of the elastic deformation unit (24).
  • the deformation amount of the elastic deformation portion (24) can be obtained from the deformation amount of the detection portion (91), and the deformation amount can be reflected in, for example, the control of the driving source (101).
  • the fifth form of the internally meshing planetary gear device (1, 1A, 1B) is based on any of the first to fourth forms and further includes an annular support frame (9).
  • the gear body (22) is fixed to the support frame (9) at the inner side of the support frame (9).
  • a gap is provided between the elastic deformation portion (24) and the support frame (9).
  • the rigidity of the gear body (22) which is lowered by providing the elastic deformation portion (24) can be ensured by the support frame (9).
  • the gear body (22) has a reinforcement portion (26) having a higher rigidity than the elastic deformation portion (24) on at least one side in the tooth direction of the internal teeth (21) when viewed from the elastic deformation portion (24).
  • the elastic deformation portion (24) can be elastically deformed, it is also easy to ensure the desired rigidity of the gear body (22).
  • the seventh form of the robot joint device (200) includes: an internal meshing planetary gear device (1, 1A, 1B) of any one of the first to sixth forms; a first component (201) fixed to the gear body (22); and a second component (202) that rotates relative to the first component (201) as the planetary gear (3) rotates relative to the internal gear (2).
  • the gap (play) between the internal teeth (21) and the external teeth (31) formed by the plurality of pins (23) is filled, thereby reducing the backlash.
  • the internal meshing planetary gear device (1, 1A, 1B) there is an advantage that the internal teeth (21) and the external teeth (31) are meshed at the meshing position.
  • the gap between the teeth (31) is expanded, and the increase of the tooth gap is also easily suppressed.
  • the pins (23) held in the inner peripheral grooves (223) are pressed against the outer teeth (31) by the elastic force of the elastic deformation portion (24) of the gear body (22). Therefore, the gap (play) between the inner teeth (21) and the outer teeth (31) formed by the plurality of pins (23) is filled, thereby reducing the backlash.
  • the gap between the inner teeth (21) and the outer teeth (31) at the meshing portion of the inner teeth (21) and the outer teeth (31) is expanded, and the increase of the backlash is also easily suppressed.
  • the structures of the second to sixth forms are not essential structures for the internally meshing planetary gear device (1, 1A, 1B) and can be omitted as appropriate.

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Power Engineering (AREA)
  • Robotics (AREA)
  • Retarders (AREA)
  • Gears, Cams (AREA)

Abstract

An internal meshing planetary gear device (1, 1A) capable of easily suppressing an increase in backlash, and a joint device for a robot. The internal meshing planetary gear device (1, 1A) comprises an internal gear (2) and a planetary gear (3). The internal gear (2) has an annular gear body (22) and a plurality of pins (23). The plurality of pins (23) are held in an inner peripheral surface (221) of the gear body (22) in a self-rotating state, to form a plurality of inner peripheral grooves (223) and form inner teeth (21). The planetary gear (3) has outer teeth (31) partially meshed with the inner teeth (21). The internal meshing planetary gear device (1, 1A) rotates the planetary gear (3) relative to the internal gear (2) by swinging the planetary gear (3). The gear body (22) is provided with an elastic deformation part (24) capable of elastically deforming at a position where at least a plurality of inner peripheral grooves (223) are formed.

Description

内啮合行星齿轮装置和机器人用关节装置Internal meshing planetary gear device and joint device for robot
相关申请的交叉引用CROSS-REFERENCE TO RELATED APPLICATIONS
本申请基于申请号为申请号202211678904.0、申请日为2022年12月26日的中国专利申请提出，并要求该中国专利申请的优先权，该中国专利申请的全部内容在此引入本申请作为参考。This application is based on the Chinese patent application with application number 202211678904.0 and application date December 26, 2022, and claims the priority of the Chinese patent application. The entire content of the Chinese patent application is hereby introduced into this application as a reference.
技术领域Technical Field
本公开一般性地涉及内啮合行星齿轮装置和机器人用关节装置，更详细而言，涉及配置有在具有内齿的内齿齿轮的内侧具有外齿的行星齿轮的内啮合行星齿轮装置和机器人用关节装置。The present disclosure generally relates to an internally meshing planetary gear device and a robot joint device, and more particularly to an internally meshing planetary gear device and a robot joint device in which a planetary gear having external teeth is arranged inside an internally gear having internal teeth.
背景技术Background technique
作为关联技术，已知有称作分配型的偏心摆动型的内啮合行星齿轮装置(例如，参照专利文献1)。在关联技术的内啮合行星齿轮装置中，包括配置于从内齿齿轮的轴心偏移的位置的多个(例如3个)的曲轴，通过由曲轴齿轮同步驱动各曲轴，从而使行星齿轮(外齿齿轮)一边摆动一边与内齿齿轮内啮合。As a related art, an eccentric oscillating type internal meshing planetary gear device called a distributed type is known (for example, refer to Patent Document 1). In the internal meshing planetary gear device of the related art, a plurality of (for example, three) crankshafts are arranged at positions offset from the axis of the internal gear, and each crankshaft is synchronously driven by the crankshaft gear, so that the planetary gear (external gear) meshes with the internal gear while oscillating.
行星齿轮包含第一行星齿轮和第二行星齿轮。在第一行星齿轮和第二行星齿轮的轴向两侧配置有一对支架。各曲轴通过一对圆锥滚子轴承而被支承于一对支架。当输入齿轮旋转时，与该输入齿轮同时啮合的3个曲轴齿轮向相同的方向以相同的旋转速度进行旋转。在各曲轴齿轮花键连结有曲轴，因此3个曲轴在以与输入齿轮和曲轴齿轮的齿数比被减速了的状态下，向相同的方向以相同的旋转速度进行旋转。其结果，形成于3个曲轴的轴向相同位置的3个第一偏心部同步旋转地使第一行星齿轮摆动，并且分别形成于3个曲轴的轴向相同位置的3个第二偏心部同步旋转地使第二行星齿轮摆动。The planetary gear includes a first planetary gear and a second planetary gear. A pair of brackets are arranged on both sides of the first planetary gear and the second planetary gear in the axial direction. Each crankshaft is supported by a pair of brackets through a pair of tapered roller bearings. When the input gear rotates, the three crankshaft gears that are simultaneously meshed with the input gear rotate in the same direction at the same rotation speed. The crankshafts are spline-connected to each crankshaft gear, so the three crankshafts rotate in the same direction at the same rotation speed in a state where the gear ratio between the input gear and the crankshaft gear is reduced. As a result, the three first eccentric portions formed at the same axial position of the three crankshafts rotate synchronously to cause the first planetary gear to swing, and the three second eccentric portions formed at the same axial position of the three crankshafts rotate synchronously to cause the second planetary gear to swing.
第一行星齿轮和第二行星齿轮分别与内齿齿轮内啮合。内齿齿轮具有：齿 轮主体；和销(销构件)，以能够旋转的方式组入齿轮主体，并构成该内齿齿轮的内齿。此处，内齿齿轮的齿数(销的根数)比各行星齿轮的齿数稍多。因此，各行星齿轮每摆动一次，第一行星齿轮和第二行星齿轮相对于内齿齿轮产生齿数差量的圆周方向的位相偏离(自转)，该自转作为绕各曲轴的内齿齿轮的旋转轴的公转传递至一对支架。由此，能够使一对支架以旋转轴为中心相对于齿轮主体(与一体化了的壳体)相对旋转。The first planetary gear and the second planetary gear are respectively meshed with the internal gear. The internal gear has: The gear body; and the pin (pin member) are rotatably assembled into the gear body and constitute the internal teeth of the internal gear. Here, the number of teeth of the internal gear (the number of pins) is slightly greater than the number of teeth of each planetary gear. Therefore, each time each planetary gear swings, the first planetary gear and the second planetary gear produce a circumferential phase deviation (rotation) in the amount of the difference in the number of teeth relative to the internal gear, and the rotation is transmitted to a pair of brackets as a revolution around the rotation axis of the internal gear of each crankshaft. As a result, the pair of brackets can be relatively rotated relative to the gear body (and the integrated housing) around the rotation axis.
现有技术文献Prior art literature
专利文献Patent Literature
专利文献1：日本特开2016-75354号公报Patent Document 1: Japanese Patent Application Publication No. 2016-75354
发明内容Summary of the invention
在上述关联技术的结构中，例如，由于长期的使用或高负荷下的使用等使用环境，而可能在行星齿轮的外齿产生磨损，从而增大齿隙(backlash)。In the above-mentioned related art structure, due to a use environment such as long-term use or use under a high load, for example, wear may occur on the outer teeth of the planetary gear, thereby increasing backlash.
本公开的目的在于提供容易抑制齿隙的增大的内接合行星齿轮装置和机器人用关节装置。An object of the present disclosure is to provide an internally meshing planetary gear device and a robot joint device that can easily suppress an increase in backlash.
用于解决技术问题的方案Solutions for solving technical problems
本公开的一方式的内啮合行星齿轮装置包括内齿齿轮和行星齿轮，通过使所述行星齿轮摆动，从而使所述行星齿轮相对于所述内齿齿轮相对旋转。所述内齿齿轮具有：环状的齿轮主体；和多个销，以能够自转的状态保持于在所述齿轮主体的内周面形成的多个内周槽，并构成内齿。所述行星齿轮具有与所述内齿局部性地啮合的外齿。所述齿轮主体在至少形成有所述多个内周槽的部位具有能够弹性变形的弹性变形部。An internally meshing planetary gear device of one embodiment of the present disclosure includes an internal gear and a planetary gear, and the planetary gear is caused to rotate relative to the internal gear by swinging the planetary gear. The internal gear has: an annular gear body; and a plurality of pins, which are held in a plurality of inner peripheral grooves formed on the inner peripheral surface of the gear body in a state capable of self-rotation and constitute internal teeth. The planetary gear has external teeth partially meshing with the internal teeth. The gear body has an elastically deformable portion capable of elastic deformation at least at a portion where the plurality of inner peripheral grooves are formed.
本公开的一方式的机器人用关节装置机器人用关节装置包括：所述内啮合行星齿轮装置；第一构件，固定于所述齿轮主体；和第二构件，伴随着所述行星齿轮相对于所述内齿齿轮的相对旋转而相对于所述第一构件相对旋转。A robot joint device according to one embodiment of the present disclosure includes: the internally meshing planetary gear device; a first member fixed to the gear body; and a second member that rotates relative to the first member as the planetary gear rotates relative to the internal gear.
发明效果Effects of the Invention
根据本公开，能够提供容易抑制齿隙的增大的内接合行星齿轮装置和机器 人用关节装置。According to the present disclosure, it is possible to provide an internally meshed planetary gear device and a machine that can easily suppress an increase in backlash. Human joint device.
附图说明BRIEF DESCRIPTION OF THE DRAWINGS
图1是示出包含基本结构的内啮合行星齿轮装置的执行器的概略结构的立体图。FIG. 1 is a perspective view showing a schematic structure of an actuator including an internally meshing planetary gear device having a basic structure.
图2是上述的内啮合行星齿轮装置的从旋转轴的输入侧观察到的概略的分解立体图。FIG. 2 is a schematic exploded perspective view of the internally meshing planetary gear device as viewed from the input side of the rotating shaft.
图3是上述的内啮合行星齿轮装置的从旋转轴的输出侧观察到的概略的分解立体图。FIG. 3 is a schematic exploded perspective view of the internally meshing planetary gear device as viewed from the output side of the rotating shaft.
图4是上述的内啮合行星齿轮装置的概略剖视图。FIG. 4 is a schematic cross-sectional view of the internally meshing planetary gear device described above.
图5是示出上述的内啮合行星齿轮装置的、图4的A1-A1线剖视图。FIG. 5 is a cross-sectional view taken along line A1 - A1 of FIG. 4 , showing the internally meshing planetary gear device described above.
图6是示出上述的内啮合行星齿轮装置的、图4的B1-B1线剖视图。FIG. 6 is a cross-sectional view taken along line B1 - B1 of FIG. 4 , showing the internally meshing planetary gear device described above.
图7是实施方式一的内啮合行星齿轮装置的概略剖视图。FIG. 7 is a schematic cross-sectional view of the internally meshing planetary gear device according to the first embodiment.
图8是示出上述的内啮合行星齿轮装置的主要部分，是图7的区域Z1的概略放大图。FIG. 8 shows a main part of the internally meshing planetary gear device described above, and is a schematic enlarged view of the area Z1 of FIG. 7 .
图9示出上述的内啮合行星齿轮装置的主要部分，是仅示出齿轮主体和支承框的分解立体图。FIG. 9 shows the main part of the internally meshing planetary gear device described above, and is an exploded perspective view showing only the gear body and the support frame.
图10示出上述的内啮合行星齿轮装置的主要部分，是仅示出齿轮主体和销的图8的A1-A1线剖视图。FIG. 10 shows a main part of the internally meshing planetary gear device described above, and is a cross-sectional view taken along line A1 - A1 of FIG. 8 showing only the gear body and the pins.
图11是示出使用了上述的内啮合行星齿轮装置的机器人用关节装置的概略图。FIG. 11 is a schematic diagram showing a robot joint device using the internal meshing planetary gear device described above.
图12A示出变形例的内啮合行星齿轮装置的主要部分，是相当于图7的区域Z1的概略放大图。FIG. 12A shows a main part of an internally meshing planetary gear device according to a modified example, and is a schematic enlarged view corresponding to the area Z1 of FIG. 7 .
图12B示出变形例的内啮合行星齿轮装置的主要部分，是相当于图7的区域Z1的概略放大图。FIG. 12B shows a main part of the internally meshing planetary gear device according to the modified example, and is a schematic enlarged view corresponding to the area Z1 of FIG. 7 .
图13示出实施方式二的内啮合行星齿轮装置的主要部分，是相当于图7的区域Z1的概略放大图。 FIG. 13 shows a main part of the internally meshing planetary gear device according to the second embodiment, and is a schematic enlarged view corresponding to the area Z1 of FIG. 7 .
具体实施方式Detailed ways
(基本结构)(basic structure)
(1)概要(1) Overview
以下，关于本基本结构的内啮合行星齿轮装置1的概要，参照图1～图4进行说明。本公开参照的附图都是示意性的图，图中的各结构要素的大小及厚度各自的比未必反映实际的尺寸比。例如，图1～图4中的内齿21及外齿31的齿形、尺寸及齿数等都不过是为了说明而示意性地表示的，其主旨并不限定为图示的形状。The following is an overview of the internal meshing planetary gear device 1 of the basic structure, with reference to FIGS. 1 to 4. The drawings referred to in the present disclosure are all schematic drawings, and the size and thickness ratios of the structural elements in the drawings do not necessarily reflect the actual size ratios. For example, the tooth shape, size, and number of teeth of the internal teeth 21 and the external teeth 31 in FIGS. 1 to 4 are only schematically shown for the purpose of explanation, and the subject matter is not limited to the shapes shown in the drawings.
本基本结构的内啮合行星齿轮装置1(以下，也简称为“齿轮装置1”)是包括内齿齿轮2和行星齿轮3的齿轮装置。在该齿轮装置1中，通过在环状的内齿齿轮2的内侧配置行星齿轮3，并使行星齿轮3摆动，从而使行星齿轮3相对于内齿齿轮2相对旋转。另外，内啮合行星齿轮装置1还包括轴承构件6，轴承构件6具有外圈62及内圈61。内圈61配置于外圈62的内侧，并被支承为能够相对于外圈62相对地旋转。特别是本基本结构的齿轮装置1是称作分配型的偏心摆动型的内啮合行星齿轮装置。The internal meshing planetary gear device 1 (hereinafter, also simply referred to as "gear device 1") of this basic structure is a gear device including an internal gear 2 and a planetary gear 3. In the gear device 1, the planetary gear 3 is arranged on the inner side of the annular internal gear 2 and the planetary gear 3 is swung, so that the planetary gear 3 rotates relative to the internal gear 2. In addition, the internal meshing planetary gear device 1 also includes a bearing component 6, and the bearing component 6 has an outer ring 62 and an inner ring 61. The inner ring 61 is arranged on the inner side of the outer ring 62 and is supported so as to be relatively rotatable relative to the outer ring 62. In particular, the gear device 1 of this basic structure is an internal meshing planetary gear device of an eccentric swing type called a distribution type.
如图1～图4所示，本基本结构的齿轮装置1包括配置于从内齿齿轮2的轴心(旋转轴Ax1)偏移的位置的多个(在基本结构中为3个)的曲轴(偏心轴)7A、7B、7C。进一步，齿轮装置1包括配置于内齿齿轮2的轴心(旋转轴Ax1)上的、以旋转轴Ax1为中心的输入轴500和与输入轴500一体形成的输入齿轮501。曲轴齿轮502A、502B、502C分别通过花键连结于多个曲轴7A、7B、7C。这些多个(在基本结构中为3个)的曲轴齿轮502A、502B、502C以与输入齿轮501啮合的方式配置。因此，当驱动输入轴500时，齿轮装置1通过利用输入齿轮501来同步驱动曲轴7A、7B、7C，从而使行星齿轮3摆动。As shown in FIGS. 1 to 4 , the gear device 1 of the basic structure includes a plurality of (three in the basic structure) crankshafts (eccentric shafts) 7A, 7B, 7C arranged at positions offset from the axis (rotation axis Ax1) of the internal gear 2. Further, the gear device 1 includes an input shaft 500 arranged on the axis (rotation axis Ax1) of the internal gear 2 and centered on the rotation axis Ax1, and an input gear 501 formed integrally with the input shaft 500. Crankshaft gears 502A, 502B, 502C are connected to the plurality of crankshafts 7A, 7B, 7C by splines, respectively. These plurality of (three in the basic structure) crankshaft gears 502A, 502B, 502C are arranged in a manner meshing with the input gear 501. Therefore, when the input shaft 500 is driven, the gear device 1 drives the crankshafts 7A, 7B, 7C synchronously by using the input gear 501, thereby causing the planetary gear 3 to oscillate.
内齿齿轮2具有内齿21且固定于外圈62。特别是在本基本结构中，内齿齿轮2具有环状的齿轮主体22和多个销23。多个销23以能够自转的状态保持于齿轮主体22的内周面221而构成内齿21。行星齿轮3具有与内齿21局部性地啮合的外齿31。也就是说，在内齿齿轮2的内侧，行星齿轮3内切于内齿齿 轮2，成为外齿31的一部分与内齿21的一部分啮合的状态。在该状态下，当驱动多个曲轴7A、7B、7C时行星齿轮3摆动，内齿21与外齿31的啮合位置沿内齿齿轮2的圆周方向移动，在两齿轮(内齿齿轮2及行星齿轮3)之间产生与行星齿轮3与内齿齿轮2的齿数差对应的相对旋转。此处，如果将内齿齿轮2固定，则伴随着两齿轮的相对旋转，行星齿轮3旋转(自转)。其结果，从行星齿轮3能够得到与两齿轮的齿数差相应地以比较高的减速比被减速了的旋转输出。The internal gear 2 has internal teeth 21 and is fixed to the outer ring 62. In particular, in this basic structure, the internal gear 2 has an annular gear body 22 and a plurality of pins 23. The plurality of pins 23 are held on the inner circumferential surface 221 of the gear body 22 in a state where they can rotate, thereby constituting the internal teeth 21. The planetary gear 3 has external teeth 31 that partially mesh with the internal teeth 21. That is, on the inner side of the internal gear 2, the planetary gear 3 is inscribed in the internal teeth. The planetary gear 2 is in a state where a part of the external teeth 31 is meshed with a part of the internal teeth 21. In this state, when the plurality of crankshafts 7A, 7B, and 7C are driven, the planetary gear 3 swings, and the meshing position of the internal teeth 21 and the external teeth 31 moves along the circumferential direction of the internal gear 2, and a 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 (the internal gear 2 and the planetary gear 3). Here, if the internal gear 2 is fixed, the planetary gear 3 rotates (rotates) along with the relative rotation of the two gears. As a result, a rotation output that is reduced in speed at a relatively high reduction ratio corresponding to the difference in the number of teeth between the two gears can be obtained from the planetary gear 3.
这种齿轮装置1以下述方式使用：将行星齿轮3的相当于自转分量的旋转作为与轴承构件6的内圈61一体化的一对支架18、19的旋转而取出。由此，齿轮装置1以输入轴500为输入侧，以一对支架18、19为输出侧，作为比较高的减速比的齿轮装置发挥功能。因此，在本基本结构的齿轮装置1中，为了将行星齿轮3的相当于自转分量的旋转向一对支架18、19传递而利用一对支架18、19支承多个曲轴7A、7B、7C。一对支架18、19配置于行星齿轮3的轴向(沿着旋转轴Ax1的方向)的两侧，并以能够旋转的方式支承各曲轴7A、7B、7C。This gear device 1 is used in the following manner: the rotation corresponding to the self-rotation component of the planetary gear 3 is extracted as the rotation of a pair of brackets 18 and 19 integrated with the inner ring 61 of the bearing member 6. As a result, the gear device 1 functions as a gear device with a relatively high reduction ratio, with the input shaft 500 as the input side and the pair of brackets 18 and 19 as the output side. Therefore, in the gear device 1 of this basic structure, in order to transmit the rotation corresponding to the self-rotation component of the planetary gear 3 to the pair of brackets 18 and 19, a plurality of crankshafts 7A, 7B, and 7C are supported by a pair of brackets 18 and 19. The pair of brackets 18 and 19 are arranged on both sides of the axial direction (along the direction of the rotation axis Ax1) of the planetary gear 3, and support each crankshaft 7A, 7B, and 7C in a rotatable manner.
此处，多个曲轴7A、7B、7C在分别***到在行星齿轮3形成的多个开口部33的状态下，伴随着行星齿轮3的旋转而相对于内齿齿轮2相对旋转。另外，各曲轴7A、7B、7C具有轴心部71和相对于轴心部71偏心的偏心部72。一对支架18、19以能够旋转的方式支承各曲轴7A、7B、7C中的轴心部71，在行星齿轮3的开口部33***有各曲轴7A、7B、7C的偏心部72。因此，行星齿轮3的摆动成分、也就是说行星齿轮3的公转分量被偏心部72相对于轴心部71的公转分量吸收。换言之，通过各曲轴7A、7B、7C的轴心部71的偏心部72分别以相对于轴心部71公转的方式旋转来吸收行星齿轮3的摆动成分。因此，通过多个曲轴7A、7B、7C，将除了行星齿轮3的摆动成分(公转分量)之外的、行星齿轮3的旋转(自转分量)向一对支架18、19传递。Here, the plurality of crankshafts 7A, 7B, 7C rotates relative to the internal gear 2 as the planetary gear 3 rotates while being inserted into the plurality of openings 33 formed in the planetary gear 3. In addition, each crankshaft 7A, 7B, 7C has an axial portion 71 and an eccentric portion 72 eccentric to the axial portion 71. The pair of brackets 18, 19 rotatably supports the axial portion 71 of each crankshaft 7A, 7B, 7C, and the eccentric portion 72 of each crankshaft 7A, 7B, 7C is inserted into the opening 33 of the planetary gear 3. Therefore, the swing component of the planetary gear 3, that is, the revolution component of the planetary gear 3 is absorbed by the revolution component of the eccentric portion 72 relative to the axial portion 71. In other words, the swing component of the planetary gear 3 is absorbed by the eccentric portion 72 of the axial portion 71 of each crankshaft 7A, 7B, 7C rotating in a manner of orbiting relative to the axial portion 71. Therefore, the rotation (autorotation component) of the planetary gear 3 in addition to the oscillation component (revolution component) of the planetary gear 3 is transmitted to the pair of carriers 18 and 19 via the plurality of crankshafts 7A, 7B, and 7C.
另外，如图1所示，本基本结构的齿轮装置1与驱动源101一起构成执行器100。换言之，本基本结构的执行器100包括齿轮装置1和驱动源101。驱动 源101产生用于使行星齿轮3摆动的驱动力。具体而言，驱动源101使输入轴500以旋转轴Ax1为中心旋转，由此使行星齿轮3摆动。In addition, as shown in FIG1 , the gear device 1 of this basic structure and the driving source 101 together constitute the actuator 100. In other words, the actuator 100 of this basic structure includes the gear device 1 and the driving source 101. The driving source 101 generates a driving force for oscillating the planetary gear 3. Specifically, the driving source 101 rotates the input shaft 500 about the rotation axis Ax1, thereby oscillating the planetary gear 3.
(2)定义(2) Definition
本公开所说的“环状”是指至少在俯视时如在内侧形成包围而成的空间(区域)的圈(环)那样的形状，并不限于在俯视时为正圆的圆形状(圆环状)，例如也可以是椭圆形状和多边形状等。进一步，例如，即使是杯状那样具有底部的形状，只要其周壁为环状，就包含在“环状”内。The "annular" in the present disclosure refers to a shape that is at least a circle (ring) that forms an enclosed space (region) on the inside when viewed from above, and is not limited to a circular shape (annular shape) that is a perfect circle when viewed from above, and may be, for example, an elliptical shape or a polygonal shape, etc. Furthermore, even a shape having a bottom such as a cup is included in the "annular" as long as its peripheral wall is annular.
本公开所说的“公转”是指某物体环绕通过该物体的中心(重心)的中心轴以外的旋转轴转圈，当某物体公转时，该物体的中心沿着以旋转轴为中心的公转轨道移动。因此，例如，在某物体以与通过该物体的中心(重心)的中心轴平行的偏心轴为中心旋转的情况下，该物体以偏心轴为旋转轴公转。作为一例，行星齿轮3通过摆动而绕旋转轴Ax1转圈地在内齿齿轮2内公转。The term "revolution" as used in this disclosure means that an object revolves around a rotation axis other than a central axis passing through the center (center of gravity) of the object. When an object revolves, the center of the object moves along a revolving orbit centered on the rotation axis. Therefore, for example, when an object revolves around an eccentric axis parallel to the central axis passing through the center (center of gravity) of the object, the object revolves around the eccentric axis as the rotation axis. As an example, the planetary gear 3 revolves around the rotation axis Ax1 in the internal gear 2 by swinging.
另外，在公开中，有将旋转轴Ax1的一方侧(图4的左侧)称为“输出侧”，将旋转轴Ax1的另一方侧(图4的右侧)称为“输入侧”的情况。在图4的例子中，从旋转轴Ax1的“输入侧”向输入轴500赋予旋转，从旋转轴Ax1的“输出侧”取出一对支架18、19的旋转。但是，“输入侧”及“输出侧”只不过是为了说明而赋予的标签，其主旨并不限定从齿轮装置1观察按到的、输入及输出的位置关系。In addition, in the disclosure, one side of the rotation axis Ax1 (the left side of FIG. 4 ) is referred to as the “output side”, and the other side of the rotation axis Ax1 (the right side of FIG. 4 ) is referred to as the “input side”. In the example of FIG. 4 , rotation is imparted to the input shaft 500 from the “input side” of the rotation axis Ax1, and rotation of a pair of brackets 18 and 19 is taken out from the “output side” of the rotation axis Ax1. However, the “input side” and “output side” are merely labels given for the purpose of explanation, and their purpose does not limit the positional relationship between the input and the output as viewed from the gear device 1.
在本公开中所说的“旋转轴”是指成为旋转体的旋转运动的中心的虚拟性的轴(直线)。也就是说，旋转轴Ax1是不伴有实体的虚拟轴。输入轴500以旋转轴Ax1为中心进行旋转运动。The "rotation axis" referred to in the present disclosure refers to a virtual axis (straight line) that is the center of rotation of a rotating body. That is, the rotation axis Ax1 is a virtual axis without a physical body. The input shaft 500 rotates around the rotation axis Ax1.
在本公开所说的“内齿”和“外齿”分别指多个“齿”的集合(组)而不是单体的“齿”。也就是说，内齿齿轮2的内齿21由配置于内齿齿轮2(齿轮主体22)的内周面221的多个齿的集合构成。同样，行星齿轮3的外齿31由配置于行星齿轮3的外周面的多个齿的集合构成。In the present disclosure, the "internal teeth" and "external teeth" refer to a collection (group) of multiple "teeth" rather than a single "tooth". That is, the internal teeth 21 of the internal gear 2 are composed of a collection of multiple 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 collection of multiple teeth arranged on the outer peripheral surface of the planetary gear 3.
(3)结构(3) Structure
以下、关于本基本结构的内啮合行星齿轮装置1的详细的结构，参照图1～ 图6进行说明。1 to 2, the detailed structure of the internal meshing planetary gear device 1 of the basic structure will be described. Figure 6 is used for illustration.
图1是示出包含齿轮装置1的执行器100的概略结构的立体图。在图1中，示意性地示出驱动源101。图2是齿轮装置1的从旋转轴Ax1的输入侧观察到的概略的分解立体图。图3是齿轮装置1的从旋转轴Ax1的输出侧观察到的概略的分解立体图。图4是齿轮装置1的概略剖视图。图5是图4的A1-A1线剖视图。图6是图4的B1-B1线剖视图。其中，在图5和图6中，关于曲轴7A、7B、7C以外的部件，虽然也是剖面但是省略了剖面线。FIG. 1 is a perspective view showing a schematic structure of an actuator 100 including a gear device 1. In FIG. 1 , a driving source 101 is schematically shown. FIG. 2 is a schematic exploded perspective view of the gear device 1 as viewed from the input side of the rotating shaft Ax1. FIG. 3 is a schematic exploded perspective view of the gear device 1 as viewed from the output side of the rotating shaft Ax1. FIG. 4 is a schematic cross-sectional view of the gear device 1. FIG. 5 is a cross-sectional view taken along the line A1-A1 of FIG. 4. FIG. 6 is a cross-sectional view taken along the line B1-B1 of FIG. 4. In FIG. 5 and FIG. 6 , although the components other than the crankshafts 7A, 7B, and 7C are also cross-sectional, the section lines are omitted.
(3.1)整体结构(3.1) Overall structure
如图1～图4所示，本基本结构的齿轮装置1包括内齿齿轮2、行星齿轮3、轴承构件6、多个曲轴7A、7B、7C、一对支架18、19和输入轴500。另外，在本基本结构中，齿轮装置1还包括输入齿轮501、多个曲轴齿轮502A、502B、502C、一对滚动轴承41、42、偏心体轴承5和壳体10。在本基本结构中，作为齿轮装置1的结构要素的内齿齿轮2、行星齿轮3、多个曲轴7A、7B、7C和一对支架18、19等的材质是不锈钢、铸铁、机械结构用碳素钢、铬钼钢、磷青铜或铝青铜等金属、或者铝或钛等轻金属。此处所说的金属包括实施了氮化处理等表面处理的金属。As shown in FIGS. 1 to 4 , the gear device 1 of this basic structure includes an internal gear 2, a planetary gear 3, a bearing member 6, a plurality of crankshafts 7A, 7B, 7C, a pair of brackets 18, 19, and an input shaft 500. In addition, in this basic structure, the gear device 1 also includes an input gear 501, a plurality of crankshaft gears 502A, 502B, 502C, a pair of rolling bearings 41, 42, an eccentric bearing 5, and a housing 10. In this basic structure, the internal gear 2, the planetary gear 3, the plurality of crankshafts 7A, 7B, 7C, and a pair of brackets 18, 19, which are structural elements of the gear device 1, are made of metals such as stainless steel, cast iron, carbon steel for mechanical structures, chrome-molybdenum steel, phosphor bronze or aluminum bronze, or light metals such as aluminum or titanium. The metal mentioned here includes metals subjected to surface treatment such as nitriding treatment.
另外，在本基本结构中，作为齿轮装置1的一例，例示使用了摆线类齿形的内切式行星齿轮减速装置。也就是说，本基本结构的齿轮装置1包括具有摆线类曲线齿形的内切式的行星齿轮3。In the present basic structure, an inscribed planetary gear reduction device using a cycloid tooth profile is exemplified as an example of the gear device 1. That is, the gear device 1 of the present basic structure includes an inscribed planetary gear 3 having a cycloid tooth profile.
另外，在本基本结构中，作为一例，齿轮装置1在内齿齿轮2的齿轮主体22与轴承构件6的外圈62一起固定于壳体10等固定构件的状态下使用。由此，伴随着内齿齿轮2与行星齿轮3的相对旋转，行星齿轮3相对于固定构件(壳体10等)相对地旋转。In addition, in this basic structure, 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 fixed member such as a housing 10 together with the outer ring 62 of the bearing member 6. As a result, along with the relative rotation of the internal gear 2 and the planetary gear 3, the planetary gear 3 rotates relative to the fixed member (housing 10, etc.).
进一步，在本基本结构中，在将齿轮装置1用于执行器100的情况下，通过向输入轴500施加作为输入的旋转力，从而从与轴承构件6的内圈61一体化的一对支架18、19取出作为输出的旋转力。也就是说，齿轮装置1以输入轴500的旋转为输入旋转，以与内圈61一体化的一对支架18、19的旋转作为输 出旋转进行动作。由此，在齿轮装置1中，可得到相对于输入旋转以比较高的减速比被减速了的输出旋转。Furthermore, in this basic structure, when the gear device 1 is used in the actuator 100, by applying a rotational force as an input to the input shaft 500, a rotational force as an output is taken out from the pair of brackets 18 and 19 integrated with the inner ring 61 of the bearing member 6. In other words, the gear device 1 uses the rotation of the input shaft 500 as an input rotation and the rotation of the pair of brackets 18 and 19 integrated with the inner ring 61 as an output rotation. Thus, in the gear device 1, an output rotation which is reduced in speed at a relatively high reduction ratio with respect to the input rotation can be obtained.
驱动源101是电动机(马达)等动力的产生源。由驱动源101产生的动力向齿轮装置1中的输入轴500传递。具体而言，驱动源101与输入轴500相连，由驱动源101产生的动力向输入轴500传递。由此，驱动源101能够使输入轴500旋转。The driving source 101 is a power generating source such as an electric motor. The power generated by the driving source 101 is transmitted to the input shaft 500 in the gear device 1. Specifically, the driving source 101 is connected to the input shaft 500, and the power generated by the driving source 101 is transmitted to the input shaft 500. Thus, the driving source 101 can rotate the input shaft 500.
进一步，在本基本结构的齿轮装置1中，如图4所示，输入侧的旋转轴Ax1与输出侧的旋转轴Ax1处于同一直线上。换言之，输入侧的旋转轴Ax1与输出侧的旋转轴Ax1为同轴。此处，输入侧的旋转轴Ax1是被赋予输入旋转的输入轴500的旋转中心，输出侧的旋转轴Ax1是产生输出旋转的内圈61(及一对支架18、19)的旋转中心。也就是说，在齿轮装置1中，能够在同轴上相对于输入旋转而得到以比较高的减速比被减速了的输出旋转。Furthermore, in the gear device 1 of this basic structure, as shown in FIG4 , the rotation axis Ax1 on the input side and the rotation axis 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 input shaft 500 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 a pair of brackets 18, 19) that generates the output rotation. That is, in the gear device 1, it is possible to obtain an output rotation that is reduced at a relatively high reduction ratio on the same axis relative to the input rotation.
如图5和图6所示，内齿齿轮2是具有内齿21的环状的部件。在本基本结构中，内齿齿轮2具有至少内周面在俯视观察下为正圆的圆环状。在圆环状的内齿齿轮2的内周面，沿着内齿齿轮2的圆周方向形成有内齿21。构成内齿21的多个齿全部为同一形状，且等间距地设置于内齿齿轮2的内周面的圆周方向的整个区域。也就是说，内齿21的节圆在俯视观察下为正圆。内齿21的节圆的中心处于旋转轴Ax1上。另外，内齿齿轮2沿旋转轴Ax1的方向具有规定的厚度。内齿21的齿向均与旋转轴Ax1平行。内齿21的齿向方向的尺寸比内齿齿轮2的厚度方向稍小。As shown in FIG. 5 and FIG. 6 , the internal gear 2 is an annular component having internal teeth 21. In this basic structure, the internal gear 2 has an annular shape whose at least inner circumference is a perfect circle when viewed from above. On the inner circumference of the annular internal gear 2, internal teeth 21 are formed along the circumferential direction of the internal gear 2. The plurality of teeth constituting the internal teeth 21 are all of the same shape and are arranged at equal intervals over the entire area of the inner circumferential direction of the internal gear 2. In other words, the pitch circle of the internal teeth 21 is a perfect circle when viewed from above. The center of the pitch circle of the internal teeth 21 is on the rotation axis Ax1. In addition, the internal gear 2 has a predetermined thickness along the direction of the rotation axis Ax1. The tooth directions of the internal teeth 21 are all parallel to the rotation axis Ax1. The dimension of the internal teeth 21 in the tooth direction is slightly smaller than that in the thickness direction of the internal gear 2.
此处，如上所述，内齿齿轮2具有环状(圆环状)的齿轮主体22和多个销23。多个外销23以能够自转的状态保持于齿轮主体22的内周面221，构成内齿21。换言之，多个销23分别作为构成内齿21的多个齿发挥功能。具体而言，如图2所示，在齿轮主体22的内周面221在圆周方向的整个区域形成有多个内周槽223。多个内周槽223全部为同一形状，且以等间距地设置。多个内周槽223均与旋转轴Ax1平行，并遍及齿轮主体22的厚度方向的全长地形成。多个销23以嵌于多个内周槽223的方式组合于齿轮主体22。多个销23各自被保持 为能够在内周槽223内自转的状态。另外，齿轮主体22(与外圈62一起)固定于壳体10。进一步，在齿轮主体22形成有固定用的多个固定孔222(参照图5)。Here, as described above, the internal gear 2 has an annular (ring-shaped) gear body 22 and a plurality of pins 23. The plurality of outer pins 23 are held on the inner circumferential surface 221 of the gear body 22 in a state capable of self-rotation, and constitute the internal teeth 21. In other words, the plurality of pins 23 function as a plurality of teeth constituting the internal teeth 21. Specifically, as shown in FIG. 2 , a plurality of inner circumferential grooves 223 are formed on the inner circumferential surface 221 of the gear body 22 over the entire area in the circumferential direction. The plurality of inner circumferential grooves 223 are all of the same shape and are arranged at equal intervals. The plurality of inner circumferential grooves 223 are all parallel to the rotation axis Ax1 and are formed over the entire length in the thickness direction of the gear body 22. The plurality of pins 23 are combined with the gear body 22 in a manner of being embedded in the plurality of inner circumferential grooves 223. The plurality of pins 23 are each held The gear body 22 is in a state of being able to rotate in the inner peripheral groove 223. The gear body 22 (together with the outer ring 62) is fixed to the housing 10. Furthermore, the gear body 22 is formed with a plurality of fixing holes 222 for fixing (see FIG. 5 ).
如图5和图6所示，行星齿轮3是具有外齿31的环状的部件。在本基本结构中，行星齿轮3具有至外周面在俯视观察下成为正圆的圆环状。在圆环状的行星齿轮3的外周面，沿着行星齿轮3的圆周方向形成有外齿31。构成外齿31的多个齿全部为同一形状，且等间距地设置于行星齿轮3的外周面的圆周方向的整个区域。也就是说，外齿31的节圆在俯视观察下为正圆。另外，行星齿轮3沿旋转轴Ax1的方向具有规定的厚度。外齿31均遍及行星齿轮3的厚度方向的全长地形成。外齿31的齿向都与旋转轴Ax1平行。在行星齿轮3中，与内齿齿轮2不同，外齿31与行星齿轮3的主体由一个金属构件一体形成。As shown in FIGS. 5 and 6 , the planetary gear 3 is an annular component having external teeth 31. In this basic structure, the planetary gear 3 has an annular shape whose outer peripheral surface is a perfect circle when viewed from above. On the outer peripheral surface of the annular planetary gear 3, external teeth 31 are formed along the circumferential direction of the planetary gear 3. The plurality of teeth constituting the external teeth 31 are all of the same shape and are arranged at equal intervals over the entire area of the circumferential direction of the outer peripheral surface of the planetary gear 3. In other words, the pitch circle of the external teeth 31 is a perfect circle when viewed from above. In addition, the planetary gear 3 has a predetermined thickness in the direction of the rotation axis Ax1. The external teeth 31 are formed over the entire length of the planetary gear 3 in the thickness direction. The tooth directions of the external teeth 31 are parallel to the rotation axis Ax1. In the planetary gear 3, unlike the internal gear 2, the external teeth 31 are formed integrally with the main body of the planetary gear 3 by a metal member.
另外，本基本结构的齿轮装置1包括多个行星齿轮3。具体而言，齿轮装置1包括第一行星齿轮301和第二行星齿轮302这两个行星齿轮3。2个行星齿轮3以在与旋转轴Ax1平行的方向上相对的方式配置。也就是说，行星齿轮3包含沿与旋转轴Ax1平行的方向(轴向)并列的第一行星齿轮301及第二行星齿轮302。第一行星齿轮301和第二行星齿轮302的形状自身通用。In addition, the gear device 1 of this basic structure includes a plurality of planetary gears 3. Specifically, the gear device 1 includes two planetary gears 3, namely, a first planetary gear 301 and a second planetary gear 302. The two planetary gears 3 are arranged in a manner opposite to each other in a direction parallel to the rotation axis Ax1. That is, the planetary gear 3 includes a first planetary gear 301 and a second planetary gear 302 arranged in parallel in a direction (axial direction) parallel to the rotation axis Ax1. The shapes of the first planetary gear 301 and the second planetary gear 302 are common in themselves.
这些两个行星齿轮3(第一行星齿轮301及第二行星齿轮302)绕着旋转轴Ax1以180度的位相差配置。在图4的例子中，第一行星齿轮301及第二行星齿轮302中的、位于旋转轴Ax1的输入侧(图4的右侧)的第一行星齿轮301的中心(外齿31的节圆的中心)C1处于相对于旋转轴Ax1向图的上方偏离(偏移)的状态。另一方面，位于旋转轴Ax1的输出侧(图4的左侧)的第二行星齿轮302的中心(外齿31的节圆的中心)C2处于相对于旋转轴Ax1向图的下方偏离(偏移)的状态。此处，旋转轴Ax1与中心C1之间的距离ΔL1为第一行星齿轮301相对于旋转轴Ax1的偏心量，旋转轴Ax1与中心C2之间的距离ΔL2为第二行星齿轮302相对于旋转轴Ax1的偏心量。这样，多个行星齿轮3在以旋转轴Ax1为中心的周向上均等地配置，由此能够取得多个行星齿轮3间的重量与载荷的平衡。 These two planetary gears 3 (the first planetary gear 301 and the second planetary gear 302) are arranged with a phase difference of 180 degrees around the rotation axis Ax1. In the example of FIG. 4, the center (the center of the pitch circle of the external teeth 31) C1 of the first planetary gear 301 located on the input side (right side of FIG. 4) of the rotation axis Ax1 is in a state of being deviated (offset) upward in the figure relative to the rotation axis Ax1. On the other hand, the center (the center of the pitch circle of the external teeth 31) C2 of the second planetary gear 302 located on the output side (left side of FIG. 4) of the rotation axis Ax1 is in a state of being deviated (offset) downward in the figure relative to the rotation axis Ax1. Here, the distance ΔL1 between the rotation axis Ax1 and the center C1 is the eccentricity of the first planetary gear 301 relative to the rotation axis Ax1, and the distance ΔL2 between the rotation axis Ax1 and the center C2 is the eccentricity of the second planetary gear 302 relative to the rotation axis Ax1. In this way, the plurality of planetary gears 3 are evenly arranged in the circumferential direction around the rotation axis Ax1 , thereby achieving a balance between the weight and the load among the plurality of planetary gears 3 .
在第一行星齿轮301与第二行星齿轮302中，它们的中心C1、C2相对于旋转轴Ax1位于180度旋转对称。在本基本结构中，对于偏心量ΔL1与偏心量ΔL2而言，从旋转轴Ax1观察到的朝向虽然相反，但是它们的绝对值相同。The centers C1 and C2 of the first planetary gear 301 and the second planetary gear 302 are 180 degrees rotationally symmetrical with respect to the rotation axis Ax1. In this basic structure, the eccentricity ΔL1 and the eccentricity ΔL2 have opposite directions when viewed from the rotation axis Ax1, but have the same absolute values.
更详细地说，各曲轴7A、7B、7C分别相对于1轴心部71具有2个偏心部72。这些2个偏心部72的中心C0的距轴心部71的中心(轴心Ax2)的偏心量ΔL0(参照图5和图6)分别与第一行星齿轮301和第二行星齿轮302相对于旋转轴Ax1的偏心量ΔL1、ΔL2相同。多个曲轴7A、7B、7C的形状自身通用。关于多个曲轴齿轮502A、502B、502C，它们的形状自身通用。More specifically, each crankshaft 7A, 7B, 7C has two eccentric portions 72 with respect to one axial portion 71. The eccentricity ΔL0 (see FIGS. 5 and 6 ) of the center C0 of the two eccentric portions 72 from the center (axial center Ax2) of the axial portion 71 is the same as the eccentricity ΔL1 and ΔL2 of the first planetary gear 301 and the second planetary gear 302 with respect to the rotation axis Ax1, respectively. The shapes of the plurality of crankshafts 7A, 7B, 7C are the same. The shapes of the plurality of crankshaft gears 502A, 502B, 502C are the same.
另外，在第一行星齿轮301和第二行星齿轮302的与旋转轴Ax1平行的方向(轴向)的两侧配置有一对支架18、19。在将一对支架18、19相互区别的情况下，将位于旋转轴Ax1的输入侧(在图4中为右侧)的支架18称为“输入侧支架18”，将位于旋转轴Ax1的输出侧(在图4中为左侧)的支架19称为“输出侧支架19”。各曲轴7A、7B、7C的两端部隔着滚动轴承41、42被保持于一对支架18、19。也就是说，各曲轴7A、7B、7C相对于行星齿轮3在与旋转轴Ax1平行的方向(轴向)的两侧处以能够自转的状态被保持于输入侧支架18和输出侧支架19。In addition, a pair of brackets 18 and 19 are arranged on both sides of the first planetary gear 301 and the second planetary gear 302 in the direction parallel to the rotation axis Ax1 (axial direction). When the pair of brackets 18 and 19 are distinguished from each other, the bracket 18 located on the input side (right side in FIG. 4) of the rotation axis Ax1 is referred to as the "input side bracket 18", and the bracket 19 located on the output side (left side in FIG. 4) of the rotation axis Ax1 is referred to as the "output side bracket 19". Both ends of each crankshaft 7A, 7B, 7C are held by the pair of brackets 18 and 19 via rolling bearings 41 and 42. That is, each crankshaft 7A, 7B, 7C is held by the input side bracket 18 and the output side bracket 19 in a rotatable state at both sides in the direction parallel to the rotation axis Ax1 (axial direction) with respect to the planetary gear 3.
在各曲轴7A、7B、7C的偏心部72装配有偏心体轴承5。在第一行星齿轮301和第二行星齿轮302分别形成有与3个曲轴7A、7B、7C对应的3个开口部33。并且，在各开口部33收容有偏心体轴承5。换言之，在第一行星齿轮301和第二行星齿轮302分别安装有偏心体轴承5，并将各曲轴7A、7B、7C***偏心体轴承5，由此偏心体轴承5和各曲轴7A、7B、7C与行星齿轮3组合。在行星齿轮3组合有偏心体轴承5和曲轴7A、7B、7C的状态下，当各曲轴7A、7B、7C旋转时，行星齿轮3绕着旋转轴Ax1摆动。The eccentric body bearing 5 is mounted on the eccentric portion 72 of each crankshaft 7A, 7B, 7C. Three openings 33 corresponding to the three crankshafts 7A, 7B, 7C are formed in the first planetary gear 301 and the second planetary gear 302, respectively. And the eccentric body bearing 5 is accommodated in each opening 33. In other words, the eccentric body bearing 5 is mounted on the first planetary gear 301 and the second planetary gear 302, respectively, and the crankshafts 7A, 7B, 7C are inserted into the eccentric body bearing 5, thereby combining the eccentric body bearing 5 and the crankshafts 7A, 7B, 7C with the planetary gear 3. In the state where the planetary gear 3 is combined with the eccentric body bearing 5 and the crankshafts 7A, 7B, 7C, when the crankshafts 7A, 7B, 7C rotate, the planetary gear 3 swings around the rotation axis Ax1.
根据以上说明的结构，通过对输入轴500施加作为输入的旋转力来使输入轴500以旋转轴Ax1为中心进行旋转，从而该旋转力从输入齿轮501被分配至多个曲轴7A、7B、7C。也就是说，当输入齿轮501旋转时，与该输入齿轮501同时啮合的3个曲轴齿轮502A、502B、502C向相同的方向以相同的旋转速度 进行旋转。在各曲轴齿轮502A、502B、502C花键连结有曲轴7A、7B、7C，因此3个曲轴7A、7B、7C在以与输入齿轮501和曲轴齿轮502A、502B、502C的齿数比被减速了的状态下，向相同的方向以相同的旋转速度进行旋转。其结果，3个曲轴7A、7B、7C中的形成于旋转轴Ax1的输入侧的相同位置的3个偏心部72同步旋转，使第一行星齿轮301摆动。进一步，3个曲轴7A、7B、7C中的形成于旋转轴Ax1的输出侧的相同位置的3个偏心部72同步旋转，使第二行星齿轮302摆动。According to the structure described above, the input shaft 500 is rotated around the rotation axis Ax1 by applying a rotation force as an input to the input shaft 500, and the rotation force is distributed from the input gear 501 to the plurality of crankshafts 7A, 7B, and 7C. That is, when the input gear 501 rotates, the three crankshaft gears 502A, 502B, and 502C that are simultaneously meshed with the input gear 501 rotate in the same direction at the same speed. The crankshafts 7A, 7B, and 7C are spline-connected to the crankshaft gears 502A, 502B, and 502C, so the three crankshafts 7A, 7B, and 7C rotate in the same direction at the same rotation speed in a state where the gear ratio between the input gear 501 and the crankshaft gears 502A, 502B, and 502C is reduced. As a result, the three eccentric portions 72 formed at the same position on the input side of the rotation axis Ax1 in the three crankshafts 7A, 7B, and 7C rotate synchronously, causing the first planetary gear 301 to oscillate. Furthermore, the three eccentric portions 72 formed at the same position on the output side of the rotation axis Ax1 in the three crankshafts 7A, 7B, and 7C rotate synchronously, causing the second planetary gear 302 to oscillate.
在图5及图6中，示出某时刻的第一行星齿轮301及第二行星齿轮302的状态。图5是图4的A1-A1线剖视图，示出第一行星齿轮301。图6是图4的B1-B1线剖视图，示出第二行星齿轮302。如图5和图6所示，在第一行星齿轮301和第二行星齿轮302中，它们的中心C1、C2相对于旋转轴Ax1位于大致180度旋转对称的位置。在本基本结构中，对于偏心量ΔL1和偏心量ΔL2而言，从旋转轴Ax1观察到的朝向虽然相反，但是它的绝对值大致相同(均为偏心量ΔL0)。根据上述的结构，轴心部71以轴心Ax2为中心旋转(自转)，由此第一行星齿轮301及第二行星齿轮302绕着旋转轴Ax1以大致180度的位相差绕着旋转轴Ax1旋转(偏心运动)。并且，多个行星齿轮3在以旋转轴Ax1为中心的周向上大致均等地配置，由此能够取得多个行星齿轮3间的重量与载荷的平衡。FIG. 5 and FIG. 6 show the states of the first planetary gear 301 and the second planetary gear 302 at a certain time. FIG. 5 is a cross-sectional view taken along the line A1-A1 of FIG. 4 , showing the first planetary gear 301. FIG. 6 is a cross-sectional view taken along the line B1-B1 of FIG. 4 , showing the second planetary gear 302. As shown in FIG. 5 and FIG. 6 , in the first planetary gear 301 and the second planetary gear 302, their centers C1 and C2 are located at positions that are approximately 180 degrees rotationally symmetrical with respect to the rotation axis Ax1. In this basic structure, although the directions of the eccentricity ΔL1 and the eccentricity ΔL2 observed from the rotation axis Ax1 are opposite, their absolute values are approximately the same (both are eccentricity ΔL0). According to the above structure, the shaft center 71 rotates (rotates) around the shaft center Ax2, and thereby the first planetary gear 301 and the second planetary gear 302 rotate (eccentric motion) around the rotation axis Ax1 with a phase difference of approximately 180 degrees around the rotation axis Ax1. Furthermore, the plurality of planetary gears 3 are arranged substantially evenly in the circumferential direction around the rotation axis Ax1 , thereby achieving a balance between the weight and the load among the plurality of planetary gears 3 .
这样构成的行星齿轮3(第一行星齿轮301及第二行星齿轮302)配置于内齿齿轮2的内侧。在俯视观察下，行星齿轮3形成的比内齿齿轮2小一圈，行星齿轮3在与内齿齿轮2组合的状态下，能够在内齿齿轮2的内侧摆动。此时，在行星齿轮3的外周面形成有外齿31，在内齿齿轮2的内周面形成有内齿21。因此，在内齿齿轮2的内侧配置有行星齿轮3的状态下，外齿31与内齿21相互相对。The planetary gears 3 (first planetary gears 301 and second planetary gears 302) thus configured are arranged on the inner side of the internal gear 2. In a plan view, the planetary gears 3 are formed to be one size smaller than the internal gear 2, and the planetary gears 3 can swing on the inner side of the internal gear 2 when combined with the internal gear 2. At this time, the outer teeth 31 are formed on the outer peripheral surface of the planetary gears 3, and the inner teeth 21 are formed on the inner peripheral surface of the internal gear 2. Therefore, when the planetary gears 3 are arranged on the inner side of the internal gear 2, the outer teeth 31 and the inner teeth 21 are opposite to each other.
进一步，外齿31的节圆比内齿21的节圆小一圈。并且，在第一行星齿轮301内切于内齿齿轮2的状态下，第一行星齿轮301的外齿31的节圆的中心C1处于距内齿21的节圆的中心(旋转轴Ax1)偏离了距离ΔL1的位置。同样， 在第二行星齿轮302内切于内齿齿轮2的状态下，第二行星齿轮302的外齿31的节圆的中心C2处于距内齿21的节圆的中心(旋转轴Ax1)偏离了距离ΔL2的位置。Furthermore, the pitch circle of the external teeth 31 is one circle smaller than the pitch circle of the internal teeth 21. In addition, when the first planetary gear 301 is inscribed in the internal gear 2, the center C1 of the pitch circle of the external teeth 31 of the first planetary gear 301 is located at a position that is offset by a distance ΔL1 from the center (rotation axis Ax1) of the pitch circle of the internal teeth 21. Similarly, When the second planetary gear 302 is inscribed in the internal gear 2 , the center C2 of the pitch circle of the external teeth 31 of the second planetary gear 302 is offset by a distance ΔL2 from the center of the pitch circle of the internal teeth 21 (rotation axis Ax1 ).
因此，在第一行星齿轮301和第二行星齿轮302的任一者中，外齿31与内齿21的至少一部分隔着间隙相对，如果外齿31与内齿21的齿数差为“2”以上，则圆周方向的整体不会相互啮合。但是，行星齿轮3在内齿齿轮2的内侧绕着旋转轴Ax1摆动(公转)，因此外齿31与内齿21局部性地啮合。也就是说，通过行星齿轮3(第一行星齿轮301和第二行星齿轮302)绕着旋转轴Ax1摆动，如图5和图6所示，构成外齿31的多个齿中的一部分的齿与构成内齿21的多个齿中的一部分的齿啮合。结果是，在齿轮装置1中，能够使外齿31的一部分与内齿21的一部分啮合。Therefore, in any one of the first planetary gear 301 and the second planetary gear 302, the external teeth 31 and at least a part of the internal teeth 21 are opposite to each other with a gap therebetween, and if the difference in the number of teeth between the external teeth 31 and the internal teeth 21 is "2" or more, the entirety of the circumferential direction will not mesh with each other. However, the planetary gear 3 swings (revolves) around the rotation axis Ax1 inside the internal gear 2, so the external teeth 31 and the internal teeth 21 are partially meshed. That is, by the swinging of the planetary gear 3 (the first planetary gear 301 and the second planetary gear 302) around the rotation axis Ax1, as shown in Figures 5 and 6, the teeth of a part of the multiple teeth constituting the external teeth 31 are meshed with the teeth of a part of the multiple teeth constituting the internal teeth 21. As a result, in the gear device 1, a part of the external teeth 31 can be meshed with a part of the internal teeth 21.
此处，内齿齿轮2中的内齿21的齿数比行星齿轮3的外齿31的齿数多N(N为正整数)。在本基本结构中，作为一例，N为“2”，行星齿轮3的(外齿31的)齿数比内齿齿轮2的(内齿21的)齿数少“2”。这样的行星齿轮3与内齿齿轮2的齿数差规定了齿轮装置1中的输出旋转相对于输入旋转的减速比。Here, the number of teeth of the internal teeth 21 in the internal gear 2 is N (N is a positive integer) greater than the number of teeth of the external teeth 31 of the planetary gear 3. In this basic structure, as an example, N is "2", and the number of teeth (of the external teeth 31) of the planetary gear 3 is "2" less than the number of teeth (of the internal teeth 21) of the internal gear 2. Such a difference in the number of teeth between the planetary gear 3 and the internal gear 2 defines the reduction ratio of the output rotation relative to the input rotation in the gear device 1.
另外，在本基本结构中，作为一例，第一行星齿轮301和第二行星齿轮302合起来的厚度比内齿齿轮2中的齿轮主体22的厚度小。进一步，第一行星齿轮301和第二行星齿轮302合起来的外齿31的齿向方向(与旋转轴Ax1平行的方向)的尺寸比内齿21的齿向方向(与旋转轴Ax1平行的方向)的尺寸小。换言之，在与旋转轴Ax1平行的方向上，第一行星齿轮301和第二行星齿轮302的外齿31收于内齿21的齿向的范围内。In addition, in this basic structure, as an example, the thickness of the first planetary gear 301 and the second planetary gear 302 combined is smaller than the thickness of the gear body 22 in the internal gear 2. Furthermore, the dimension of the tooth direction (direction parallel to the rotation axis Ax1) of the external teeth 31 combined with the first planetary gear 301 and the second planetary gear 302 is smaller than the dimension of the tooth direction (direction parallel to the rotation axis Ax1) of the internal teeth 21. In other words, in the direction parallel to the rotation axis Ax1, the external teeth 31 of the first planetary gear 301 and the second planetary gear 302 are within the range of the tooth direction of the internal teeth 21.
此处，第一行星齿轮301和第二行星齿轮302分别与内齿齿轮2内啮合。因此，第一行星齿轮301及第二行星齿轮302每摆动一次，第一行星齿轮301和第二行星齿轮302相对于内齿齿轮2产生(内齿21与外齿31的)齿数差分的圆周方向的位相偏离，并进行自转。该自转作为绕各曲轴7A、7B、7C的内齿齿轮2的轴心(旋转轴Ax1)的公转向一对支架18、19传递。由此，能够使一对支架18、19以旋转轴Ax1为中心相对于齿轮主体(与一体化了的壳体10) 相对旋转。Here, the first planetary gear 301 and the second planetary gear 302 are respectively meshed with the internal gear 2. Therefore, every time the first planetary gear 301 and the second planetary gear 302 swing, the first planetary gear 301 and the second planetary gear 302 produce a circumferential phase deviation of the difference in the number of teeth (internal teeth 21 and external teeth 31) relative to the internal gear 2, and rotate. This rotation is transmitted to the pair of brackets 18 and 19 as a reciprocal rotation around the axis (rotation axis Ax1) of the internal gear 2 of each crankshaft 7A, 7B, 7C. As a result, the pair of brackets 18 and 19 can be centered on the rotation axis Ax1 relative to the gear body (the housing 10 integrated with the gear body). Relative rotation.
总之，本基本结构的齿轮装置1通过配置于从转轴Ax1偏移的位置的多个曲轴7A、7B、7C使行星齿轮3摆动，并利用行星齿轮3的摆动得到旋转输出。也就是说，在齿轮装置1中，当行星齿轮3摆动，内齿21与外齿31的啮合位置沿内齿齿轮2的圆周方向移动时，在两个齿轮(内齿齿轮2及行星齿轮3)之间产生与行星齿轮3和内齿齿轮2的齿数差对应的相对旋转。此处，如果将内齿齿轮2固定，则伴随着两齿轮的相对旋转，行星齿轮3旋转(自转)。其结果是，从行星齿轮3能够得到与两齿轮的齿数差相应地以比较高的减速比被减速了的旋转输出。In summary, the gear device 1 of this basic structure causes the planetary gear 3 to oscillate by means of a plurality of crankshafts 7A, 7B, and 7C disposed at positions offset from the rotation axis Ax1, and obtains a rotation output by utilizing the oscillation of the planetary gear 3. That is, in the gear device 1, when the planetary gear 3 oscillates and the meshing position of the internal teeth 21 and the external teeth 31 moves along the circumferential direction of the internal gear 2, a 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 (the internal gear 2 and the planetary gear 3). Here, if the internal gear 2 is fixed, the planetary gear 3 rotates (rotates) along with the relative rotation of the two gears. As a result, a rotation output that is reduced in speed at a relatively high reduction ratio corresponding to the difference in the number of teeth between the two gears can be obtained from the planetary gear 3.
轴承构件6是具有外圈62及内圈61并用于取出齿轮装置1的输出作为内圈61相对于外圈62的旋转的部件。轴承构件6除了外圈62及内圈61之外，还具有多个滚动体63(参照图4)。外圈62和内圈61均为环状的部件。外圈62及内圈61均具有在俯视观察下为正圆的圆环状。内圈61比外圈62小一圈并配置于外圈62的内侧。此处，外圈62的内径比内圈61的外径大，因此在外圈62的内周面与内圈61的外周面之间产生间隙。The bearing member 6 is a component having an outer ring 62 and an inner ring 61 and used to extract the output of the gear device 1 as the rotation of the inner ring 61 relative to the outer ring 62. The bearing member 6 has a plurality of rolling elements 63 (see FIG. 4 ) in addition to the outer ring 62 and the inner ring 61. The outer ring 62 and the inner ring 61 are both annular components. The outer ring 62 and the inner ring 61 both have an annular shape that is a perfect circle when viewed from above. The inner ring 61 is one circle smaller than the outer ring 62 and is arranged on the inner side of the outer ring 62. Here, the inner diameter of the outer ring 62 is larger than the outer diameter of the inner ring 61, so a gap is generated between the inner peripheral surface of the outer ring 62 and the outer peripheral surface of the inner ring 61.
多个滚动体63配置于外圈62与内圈61之间的间隙。多个滚动体63沿外圈62的圆周方向并列配置。多个滚动体63全部为同一形状的金属部件，在外圈62的圆周方向的整个区域等间距地设置。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 in parallel along the circumferential direction of the outer ring 62. The plurality of rolling elements 63 are all metal parts of the same shape and are arranged at equal intervals over the entire circumferential area of the outer ring 62.
更详细地说，本基本结构的齿轮装置1的轴承构件6包含第一轴承构件601和第二轴承构件602。第一轴承构件601和第二轴承构件602分别由角球轴承构成。具体而言，如图4所示，从行星齿轮3观察在旋转轴Ax1的输入侧(图4的右侧)配置有第一轴承构件601，从行星齿轮3观察在旋转轴Ax1的输出侧(图4的左侧)配置有第二轴承构件602。轴承构件6通过第一轴承构件601和第二轴承构件602构成为径向的载荷、推力方向(沿着旋转轴Ax1的方向)的载荷、及对于旋转轴Ax1的弯曲力(弯曲力矩载荷)都能耐受。In more detail, the bearing member 6 of the gear device 1 of the basic structure includes a first bearing member 601 and a second bearing member 602. The first bearing member 601 and the second bearing member 602 are respectively composed of angular ball bearings. Specifically, as shown in FIG4 , the first bearing member 601 is arranged on the input side (right side of FIG4 ) of the rotation axis Ax1 when viewed from the planetary gear 3, and the second bearing member 602 is arranged on the output side (left side of FIG4 ) of the rotation axis Ax1 when viewed from the planetary gear 3. The bearing member 6 is configured by the first bearing member 601 and the second bearing member 602 to withstand radial loads, loads in the thrust direction (along the direction of the rotation axis Ax1), and bending forces (bending moment loads) with respect to the rotation axis Ax1.
此处，第一轴承构件601和第二轴承构件602相对于行星齿轮3在与旋转轴Ax1平行的方向(轴向)的两侧，在与旋转轴Ax1平行的方向上配置为相互 相反的朝向。也就是说，轴承构件6是组合了多个(此处为2个)角球轴承的“组合角球轴承”。此处，作为一例，第一轴承构件601和第二轴承构件602是承受各自的内圈61相互靠近的朝向的推力方向(沿着旋转轴Ax1的方向)的负载的“背面组合型”。进一步，在齿轮装置1中，第一轴承构件601和第二轴承构件602通过将各自的内圈61向相互靠近的方向紧固，从而对内圈61以作用适当的预压力的状态组合。Here, the first bearing member 601 and the second bearing member 602 are disposed on both sides of the planetary gear 3 in a direction parallel to the rotation axis Ax1 (axial direction) so as to be mutually spaced in a direction parallel to the rotation axis Ax1. In the opposite direction. That is, the bearing component 6 is a "combined angular ball bearing" that combines multiple (here, 2) angular ball bearings. Here, as an example, the first bearing component 601 and the second bearing component 602 are "back-to-back combination type" that bear the load in the thrust direction (along the direction of the rotation axis Ax1) in which the respective inner rings 61 approach each other. Furthermore, in the gear device 1, the first bearing component 601 and the second bearing component 602 are combined in a state where appropriate preload is applied to the inner ring 61 by tightening the respective inner rings 61 in the direction in which they approach each other.
另外，在本基本结构的齿轮装置1中，输入侧支架18和输出侧支架19相对于行星齿轮3配置于与旋转轴Ax1平行的方向的两侧，并穿过行星齿轮3的支架孔34(参照图4)而相互结合。具体而言，如图4所示，从行星齿轮3观察在旋转轴Ax1的输入侧(图4的右侧)配置有输入侧支架18，从行星齿轮3观察在旋转轴Ax1的输出侧(图4的左侧)配置有输出侧支架19。轴承构件6(第一轴承构件601和第二轴承构件602各自)的内圈61固定于输入侧支架18和输出侧支架19。在本基本结构中，作为一例，第一轴承构件601的内圈与输入侧支架18无缝地一体化。同样，第二轴承构件602的内圈与输出侧支架19无缝地一体化。In addition, in the gear device 1 of this basic structure, the input side bracket 18 and the output side bracket 19 are arranged on both sides of the planetary gear 3 in a direction parallel to the rotation axis Ax1, and are connected to each other through the bracket hole 34 (refer to FIG. 4) of the planetary gear 3. Specifically, as shown in FIG. 4, the input side bracket 18 is arranged on the input side (right side of FIG. 4) of the rotation axis Ax1 when viewed from the planetary gear 3, and the output side bracket 19 is arranged on the output side (left side of FIG. 4) of the rotation axis Ax1 when viewed from the planetary gear 3. The inner ring 61 of the bearing member 6 (the first bearing member 601 and the second bearing member 602) is fixed to the input side bracket 18 and the output side bracket 19. In this basic structure, as an example, the inner ring of the first bearing member 601 is seamlessly integrated with the input side bracket 18. Similarly, the inner ring of the second bearing member 602 is seamlessly integrated with the output side bracket 19.
输出侧支架19具有从输出侧支架19的一表面朝向旋转轴Ax1的输入侧突出的多个(作为一例为3个)的支架销191(参照图2)。这些多个支架销191分别贯通在行星齿轮3形成的多个(作为一例为3个)的支架孔34，多个支架销191的前端相对于输入侧支架18利用支架螺栓192(参照图7)来固定。此处，在支架销191与支架孔34的内周面之间确保间隙，支架销191能够在支架孔34内移动，也就是说能够相对于支架孔34的中心相对地移动。由此，在行星齿轮3摆动时，支架销191不与支架孔34的内周面接触。The output side bracket 19 has a plurality of (three as an example) bracket pins 191 (see FIG. 2 ) protruding from one surface of the output side bracket 19 toward the input side of the rotation axis Ax1. These plurality of bracket pins 191 respectively penetrate a plurality of (three as an example) bracket holes 34 formed in the planetary gear 3, and the front ends of the plurality of bracket pins 191 are fixed to the input side bracket 18 by bracket bolts 192 (see FIG. 7 ). Here, a gap is ensured between the bracket pin 191 and the inner circumferential surface of the bracket hole 34, and the bracket pin 191 can move in the bracket hole 34, that is, can move relatively to the center of the bracket hole 34. As a result, when the planetary gear 3 swings, the bracket pin 191 does not contact the inner circumferential surface of the bracket hole 34.
通过上述结构，齿轮装置1以下述方式使用：将行星齿轮3的相当于自转分量的旋转作为与轴承构件6的内圈61一体化的输入侧支架18和输出侧支架19的旋转而取出。即，在本基本结构中，行星齿轮3与内齿齿轮2之间的相对的旋转从输入侧支架18和输出侧支架19取出。在本基本结构中，作为一例，齿轮装置1以轴承构件6的外圈62(参照图4)固定于作为固定构件的壳体10 的状态进行使用。即，行星齿轮3利用多个曲轴7A、7B、7C与作为旋转构件的输入侧支架18和输出侧支架19连结，齿轮主体22固定于固定构件，因此行星齿轮3与内齿齿轮2之间的相对的旋转从旋转构件(输入侧支架18和输出侧支架19)取出。换言之，在本基本结构中，构成为行星齿轮3相对于齿轮主体22相对旋转时，将输入侧支架18和输出侧支架19的旋转力作为输出取出。With the above structure, the gear device 1 is used in the following manner: the rotation of the planetary gear 3 corresponding to the self-rotation component is extracted as the rotation of the input side bracket 18 and the output side bracket 19 integrated with the inner ring 61 of the bearing member 6. That is, in this basic structure, the relative rotation between the planetary gear 3 and the internal gear 2 is extracted from the input side bracket 18 and the output side bracket 19. In this basic structure, as an example, the gear device 1 is fixed to the housing 10 as a fixed member by the outer ring 62 of the bearing member 6 (see FIG. 4). That is, the planetary gear 3 is connected to the input side bracket 18 and the output side bracket 19 as the rotating member by using a plurality of crankshafts 7A, 7B, 7C, and the gear body 22 is fixed to the fixed member, so the relative rotation between the planetary gear 3 and the internal gear 2 is taken out from the rotating member (the input side bracket 18 and the output side bracket 19). In other words, in this basic structure, when the planetary gear 3 rotates relative to the gear body 22, the rotational force of the input side bracket 18 and the output side bracket 19 is taken out as output.
进一步，在本基本结构中，壳体10与内齿齿轮2的齿轮主体22无缝地一体化。也就是说，在与旋转轴Ax1平行的方向上，作为固定构件的齿轮主体22与壳体10无缝地连续设置。Furthermore, in this basic structure, the housing 10 is seamlessly integrated with the gear body 22 of the internal gear 2. That is, the gear body 22 as a fixed member is seamlessly and continuously provided with the housing 10 in a direction parallel to the rotation axis Ax1.
更详细而言，壳体10为圆筒状，且构成齿轮装置1的外轮廓。在本基本结构中，圆筒状的壳体10的中心轴构成为与旋转轴Ax1一致。也就是说，壳体10的至少外周面在俯视观察下(从轴向的一方观察)是以旋转轴Ax1为中心的正圆。壳体10形成为在轴向的两端面开口的圆筒状。此处，壳体10与内齿齿轮2的齿轮主体22无缝地一体化，从而壳体10及齿轮主体22作为一个部件来处理。因此，壳体10的内周面包含齿轮主体22的内周面221。进一步，在壳体10固定有轴承构件6的外圈62。也就是说，从壳体10的内周面中的齿轮主体22观察，第一轴承构件601的外圈62通过嵌入而固定于旋转轴Ax1的输入侧(图4的右侧)。另一方面，从壳体10的内周面中的齿轮主体22观察，第二轴承构件602的外圈62通过嵌入而固定于旋转轴Ax1的输出侧(图4的左侧)。In more detail, the housing 10 is cylindrical and constitutes the outer contour of the gear device 1. In this basic structure, the central axis of the cylindrical housing 10 is configured to coincide with the rotation axis Ax1. That is, at least the outer peripheral surface of the housing 10 is a perfect circle centered on the rotation axis Ax1 when viewed from above (viewed from one axial direction). The housing 10 is formed into a cylindrical shape with both end faces opened in the axial direction. Here, the housing 10 is seamlessly integrated with the gear body 22 of the internal gear 2, so that the housing 10 and the gear body 22 are treated as one component. Therefore, the inner peripheral surface of the housing 10 includes the inner peripheral surface 221 of the gear body 22. Furthermore, the outer ring 62 of the bearing member 6 is fixed to the housing 10. That is, when viewed from the gear body 22 in the inner peripheral surface of the housing 10, the outer ring 62 of the first bearing member 601 is fixed to the input side (right side of Figure 4) of the rotation axis Ax1 by being embedded. On the other hand, the outer ring 62 of the second bearing member 602 is fixed by being fitted on the output side (left side in FIG. 4 ) of the rotation axis Ax1 when viewed from the gear body 22 on the inner peripheral surface of the housing 10 .
进一步，壳体10的旋转轴Ax1的输入侧(图4的右侧)的端面由输入侧支架18来闭塞，壳体10的旋转轴Ax1的输出侧(图4的左侧)的端面由输出侧支架19来闭塞。因此，如图4所示，在被壳体10、输入侧支架18和输出侧支架19包围的空间内，收容有行星齿轮3(第一行星齿轮301和第二行星齿轮302)、多个销23和偏心体轴承5等部件。Furthermore, the end face of the input side (right side in FIG. 4 ) of the rotation axis Ax1 of the housing 10 is blocked by the input side bracket 18, and the end face of the output side (left side in FIG. 4 ) of the rotation axis Ax1 of the housing 10 is blocked by the output side bracket 19. Therefore, as shown in FIG. 4 , in the space surrounded by the housing 10, the input side bracket 18, and the output side bracket 19, the planetary gears 3 (the first planetary gear 301 and the second planetary gear 302), a plurality of pins 23, and the eccentric body bearing 5 are accommodated.
多个(在基本结构为3个)曲轴7A、7B、7C分别具有轴心部71和2个偏心部72。轴心部71具有至少外周面在俯视观察下为正圆的圆筒状。作为轴心部71的中心的轴心Ax2与旋转轴Ax1平行。多个曲轴7A、7B、7C的轴心Ax2在以旋转轴Ax1为中心的虚拟圆上，在圆周方向上等间隔地配置。各偏心部72 具有至少外周面在服饰观察下为正圆的圆盘状。各偏心部72的中心(中心轴)C0与转轴Ax1平行，并且配置在从旋转轴Ax1沿径向偏离的位置。此处，轴心Ax2与中心C0之间的距离ΔL0(参照图5和图6)成为相对于轴心部71的偏心量。偏心部72呈在轴心部71的长度方向(轴向)的中央部从轴心部71的外周面遍及整周地突出的凸缘形状。根据上述的结构，对于各曲轴7A、7B、7C而言，通过轴心部71以轴心Ax2为中心旋转(自转)，从而使得偏心部72进行偏心运动。The plurality of (three in the basic structure) crankshafts 7A, 7B, and 7C each have an axial portion 71 and two eccentric portions 72. The axial portion 71 has a cylindrical shape in which at least the outer peripheral surface is a perfect circle when viewed from above. The axial center Ax2, which is the center of the axial portion 71, is parallel to the rotation axis Ax1. The axial centers Ax2 of the plurality of crankshafts 7A, 7B, and 7C are arranged at equal intervals in the circumferential direction on a virtual circle centered on the rotation axis Ax1. Each eccentric portion 72 It has a disc shape whose at least outer peripheral surface is a perfect circle when viewed from clothing. The center (central axis) C0 of each eccentric portion 72 is parallel to the rotation axis Ax1, and is arranged at a position radially deviated from the rotation axis Ax1. Here, the distance ΔL0 (refer to Figures 5 and 6) between the axis Ax2 and the center C0 becomes the eccentricity relative to the axis portion 71. The eccentric portion 72 is in the shape of a flange protruding from the outer peripheral surface of the axis portion 71 throughout the entire circumference at the center of the length direction (axial direction) of the axis portion 71. According to the above-mentioned structure, for each crankshaft 7A, 7B, 7C, the eccentric portion 72 performs eccentric motion by rotating (rotating) the axis portion 71 around the axis Ax2.
在本基本结构中，轴心部71和2个偏心部72由1个金属构件一体形成，由此，实现无缝的曲轴7A、7B、7C。这样的形状的曲轴7A、7B、7C与偏心体轴承5一起组合于行星齿轮3。因此，在行星齿轮3组合有偏心体轴承5和曲轴7A、7B、7C的状态下，当曲轴7A、7B、7C旋转时，行星齿轮3绕着旋转轴Ax1摆动。In this basic structure, the axial center portion 71 and the two eccentric portions 72 are integrally formed by one metal member, thereby realizing a seamless crankshaft 7A, 7B, 7C. The crankshaft 7A, 7B, 7C of such a shape is combined with the eccentric body bearing 5 to the planetary gear 3. Therefore, in a state where the planetary gear 3 is combined with the eccentric body bearing 5 and the crankshaft 7A, 7B, 7C, when the crankshaft 7A, 7B, 7C rotates, the planetary gear 3 swings around the rotation axis Ax1.
偏心体轴承5是具有多个滚动体51(参照图4)、并吸收曲轴7A、7B、7C的旋转中的自转分量、并用于仅将除了曲轴7A、7B、7C的自转分量之外的曲轴7A、7B、7C的旋转也就是说曲轴7A、7B、7C的摆动分量(公转分量)向行星齿轮3传递的部件。多个滚动体51配置于各曲轴7A、7B、7C的偏心部72的外周面与行星齿轮3的各开口部33的内周面之间。也就是说，各曲轴7A、7B、7C的偏心部72作为偏心体轴承5的内圈发挥功能，行星齿轮3的各开口部33的内周面作为偏心体轴承5的外圈发挥功能。The eccentric bearing 5 has a plurality of rolling elements 51 (see FIG. 4 ), absorbs the rotational component of the crankshafts 7A, 7B, 7C, and transmits only the rotational component of the crankshafts 7A, 7B, 7C, that is, the swinging component (revolutionary component) of the crankshafts 7A, 7B, 7C, to the planetary gear 3. The plurality of rolling elements 51 are arranged between the outer peripheral surface of the eccentric portion 72 of each crankshaft 7A, 7B, 7C and the inner peripheral surface of each opening portion 33 of the planetary gear 3. That is, the eccentric portion 72 of each crankshaft 7A, 7B, 7C functions as the inner ring of the eccentric bearing 5, and the inner peripheral surface of each opening portion 33 of the planetary gear 3 functions as the outer ring of the eccentric bearing 5.
在行星齿轮3组合有偏心体轴承5和多个曲轴7A、7B、7C的状态下，当各曲轴7A、7B、7C旋转时，偏心体轴承5绕着轴心Ax2旋转(偏心运动)。此时，曲轴7A、7B、7C的自转分量由偏心体轴承5吸收。因此，通过偏心体轴承5仅将除了曲轴7A、7B、7C的自转分量之外的曲轴7A、7B、7C的旋转、也就是说曲轴7A、7B、7C的摆动分量(公转分量)向行星齿轮3传递。由此，在行星齿轮3组合有偏心体轴承5和曲轴7A、7B、7C的状态下，当曲轴7A、7B、7C旋转时，行星齿轮3绕着旋转轴Ax1摆动。In the state where the planetary gear 3 is combined with the eccentric body bearing 5 and the plurality of crankshafts 7A, 7B, 7C, when each crankshaft 7A, 7B, 7C rotates, the eccentric body bearing 5 rotates around the axis Ax2 (eccentric motion). At this time, the rotation component of the crankshaft 7A, 7B, 7C is absorbed by the eccentric body bearing 5. Therefore, only the rotation of the crankshaft 7A, 7B, 7C other than the rotation component of the crankshaft 7A, 7B, 7C, that is, the swing component (revolution component) of the crankshaft 7A, 7B, 7C is transmitted to the planetary gear 3 through the eccentric body bearing 5. Therefore, in the state where the planetary gear 3 is combined with the eccentric body bearing 5 and the crankshaft 7A, 7B, 7C, when the crankshaft 7A, 7B, 7C rotates, the planetary gear 3 swings around the rotation axis Ax1.
在上述的结构的齿轮装置1中，向输入轴500施加作为输入的旋转力，从 而输入轴500以旋转轴Ax1为中心进行旋转，由此行星齿轮3绕着旋转轴Ax1摆动(公转)。此时，行星齿轮3以在内齿齿轮2的内侧内切于内齿齿轮2且外齿31的一部分啮合于内齿21的一部分的状态摆动，因此内齿21与外齿31的啮合位置沿内齿齿轮2的圆周方向移动。由此，在两齿轮(内齿齿轮2及行星齿轮3)之间产生与行星齿轮3与内齿齿轮2的齿数差对应的相对旋转。并且，通过多个曲轴7A、7B、7C，将除了行星齿轮3的摆动分量(公转分量)之外的、行星齿轮3的旋转(自转分量)向一对支架18、19传递。其结果，从一对支架18、19获得与两齿轮的齿数差相应地以比较高的减速比被减速了的旋转输出。In the gear device 1 having the above structure, a rotational force is applied as an input to the input shaft 500. The input shaft 500 rotates around the rotation axis Ax1, and the planetary gear 3 swings (revolves) around the rotation axis Ax1. At this time, the planetary gear 3 swings in a state where it is inscribed in the inner side of the internal gear 2 and a part of the external teeth 31 meshes with a part of the internal teeth 21, so the meshing position of the internal teeth 21 and the external teeth 31 moves along the circumferential direction of the internal gear 2. As a result, a 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 (the internal gear 2 and the planetary gear 3). In addition, the rotation (autorotation component) of the planetary gear 3 in addition to the swing component (revolution component) of the planetary gear 3 is transmitted to the pair of carriers 18 and 19 through the plurality of crankshafts 7A, 7B, and 7C. As a result, a rotation output that is reduced at a relatively high reduction ratio corresponding to the difference in the number of teeth between the two gears is obtained from the pair of carriers 18 and 19.
然而，如上所述，在本基本结构的齿轮装置1中，内齿齿轮2与行星齿轮3的齿数差规定了齿轮装置1中的输出旋转相对于输入旋转的减速比。也就是说，在将内齿齿轮2的齿数设为“V1”并将行星齿轮3的齿数设为“V2”的情况下，减速比R1由下述式1表示。However, as described above, in the gear device 1 of the present basic structure, 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 relative to the input rotation in the gear device 1. That is, when the number of teeth of the internal gear 2 is set to "V1" and the number of teeth of the planetary gear 3 is set to "V2", the reduction ratio R1 is expressed by the following formula 1.
R1＝V2/(V1-V2)        (式1)R1＝V2/(V1-V2) (Formula 1)
总之，内齿齿轮2与行星齿轮3的齿数差(V1-V2)越小，则减速比R1越大。作为一例，内齿齿轮2的齿数V1为“72”，行星齿轮3的齿数V2为“70”、其齿数差(V1－V2)为“2”，因此根据上述式1，减速比R1为“35”。在该情况下，从旋转轴Ax1的输入侧观察，当各曲轴7A、7B、7C以轴心部71的轴心Ax2(参照图5和图6)为中心顺时针旋转1周(360度)时,一对支架18、19以旋转轴Ax1为中心逆时针旋转齿数差“2”的量(也就是说约10.3度)。In short, the smaller the difference in the number of teeth (V1-V2) between the internal gear 2 and the planetary gear 3 is, the larger the reduction ratio R1 is. As an example, the number of teeth V1 of the internal gear 2 is "72", the number of teeth V2 of the planetary gear 3 is "70", and the difference in the number of teeth (V1-V2) is "2", so according to the above formula 1, the reduction ratio R1 is "35". In this case, when each crankshaft 7A, 7B, 7C rotates clockwise around the axis Ax2 of the axial core 71 (refer to Figures 5 and 6) for one circle (360 degrees) when viewed from the input side of the rotation axis Ax1, the pair of brackets 18 and 19 rotate counterclockwise around the rotation axis Ax1 by the difference in the number of teeth "2" (that is, about 10.3 degrees).
根据本基本结构的齿轮装置1，这样高的减速比R1能够通过内齿齿轮2和行星齿轮3的组合来实现。进一步，在输入齿轮501与多个曲轴齿轮502A、502B、502C之间，也能够根据输入齿轮501和曲轴齿轮502A、502B、502C的齿数实现适当的减速比。结果是，作为齿轮装置1整体，能够实现高减速比。According to the gear device 1 of this basic structure, such a high reduction ratio R1 can be achieved by the combination of the internal gear 2 and the planetary gear 3. Furthermore, between the input gear 501 and the plurality of crankshaft gears 502A, 502B, 502C, an appropriate reduction ratio can also be achieved according to the number of teeth of the input gear 501 and the crankshaft gears 502A, 502B, 502C. As a result, the gear device 1 as a whole can achieve a high reduction ratio.
另外，齿轮装置1只要至少包括内齿齿轮2、行星齿轮3、曲轴7A、7B、7C和一对支架18、19即可，例如，如图4所示，还可以包括间隔件11。间隔件11在与旋转轴Ax1平行的方向(轴向)上配置于一对行星齿轮3(第一行星 齿轮301和第二行星齿轮302)之间。In addition, the gear device 1 only needs to include at least the internal gear 2, the planetary gears 3, the crankshafts 7A, 7B, 7C and a pair of brackets 18, 19, and may further include a spacer 11 as shown in FIG. 4. The spacer 11 is arranged between the pair of planetary gears 3 (first planetary gears 3) in a direction parallel to the rotation axis Ax1 (axial direction). gear 301 and the second planetary gear 302).
(实施方式一)(Implementation Method 1)
如图7～图10所示，本实施方式的内啮合行星齿轮装置1A(以下，也简称为“齿轮装置1A”)主要是齿轮主体22的结构和曲轴7A、7B、7C周边的结构与基本结构的齿轮装置1不同。以下，关于与基本结构同样的结构，标注相同的附图标记而适当省略说明。图7是齿轮装置1A的概略剖视图。图8在图7的区域Z1的概略放大图。图9是仅示出齿轮主体22和支承框9的分解立体图。图10是仅示出齿轮主体22和销23的图8的A1-A1线剖视图。As shown in Figures 7 to 10, the internal meshing planetary gear device 1A of the present embodiment (hereinafter, also referred to as "gear device 1A") is different from the gear device 1 of the basic structure mainly in the structure of the gear body 22 and the structure around the crankshafts 7A, 7B, and 7C. Hereinafter, for the same structure as the basic structure, the same figure marks are marked and the description is appropriately omitted. Figure 7 is a schematic cross-sectional view of the gear device 1A. Figure 8 is a schematic enlarged view of the area Z1 of Figure 7. Figure 9 is an exploded three-dimensional view showing only the gear body 22 and the support frame 9. Figure 10 is an A1-A1 line cross-sectional view of Figure 8 showing only the gear body 22 and the pin 23.
如图7所示，实施方式的齿轮装置1A还包括多个油封121、122等。油封121堵塞壳体10与输出侧支架19的外周面之间的间隙。油封122堵塞在输出侧支架19的中央部形成的中央孔193。由这些多个油封121、122等密闭的空间构成润滑剂保持空间17。润滑剂保持空间17包含轴承构件6的内圈61和外圈62之间的空间。进一步，在润滑剂保持空间17内收容有多个销23、行星齿轮3、一对滚动轴承41、42和偏心体轴承5等。As shown in FIG. 7 , the gear device 1A of the embodiment further includes a plurality of oil seals 121, 122, etc. The oil seal 121 blocks the gap between the housing 10 and the outer peripheral surface of the output side bracket 19. The oil seal 122 blocks the central hole 193 formed in the central portion of the output side bracket 19. The space enclosed by these plurality of oil seals 121, 122, etc. constitutes a lubricant retaining space 17. The lubricant retaining space 17 includes a space between the inner ring 61 and the outer ring 62 of the bearing member 6. Furthermore, a plurality of pins 23, a planetary gear 3, a pair of rolling bearings 41, 42, an eccentric bearing 5, etc. are accommodated in the lubricant retaining space 17.
并且，在润滑剂保持空间17封入有润滑剂。润滑剂为液体，能够在润滑剂保持空间17内流动。因此，在齿轮装置1的使用时，例如润滑剂进入由多个外销23构成的内齿21与行星齿轮3的外齿31的啮合部位。在本公开所说的“液体”是指含有液态或凝胶态的物质。此处所说的“凝胶态”是指具有液体与固体的中间性质的状态，含有由液相与固相这两个相构成的胶体(colloid)的状态。例如，分散剂为液相且分散质为液相的乳剂(emulsion)，分散质为固相的悬浮液(suspension)等称为凝胶(gel)或溶胶(sol)的状态包含于“凝胶状”。另外，分散剂为固相且分散质为液相的状态也包含于“凝胶状”。在本基本结构中，作为一例，润滑剂是液状的润滑油(油液)。Furthermore, a lubricant is sealed in the lubricant retaining space 17. The lubricant is a liquid and can flow in the lubricant retaining space 17. Therefore, when the gear device 1 is used, for example, the lubricant enters the meshing portion between the internal teeth 21 composed of a plurality of external pins 23 and the external teeth 31 of the planetary gear 3. The "liquid" mentioned in the present disclosure refers to a substance containing a liquid or gel state. The "gel state" mentioned here refers to a state having intermediate properties between a liquid and a solid, and contains a colloid state composed of two phases, a liquid phase and a solid phase. For example, an emulsion (emulsion) in which the dispersant is a liquid phase and the dispersant is a liquid phase, a suspension (suspension) in which the dispersant is a solid phase, etc. are called gel (gel) or sol (sol) and are included in the "gel state". In addition, a state in which the dispersant is a solid phase and the dispersant is a liquid phase is also included in the "gel state". In this basic structure, as an example, the lubricant is a liquid lubricating oil (oil).
本实施方式的齿轮装置1A还包括安装于支架18、19的轴向的两侧的一对罩13、14。在将一对罩13、14相互区别的情况下，将位于旋转轴Ax1的输入侧(在图7中为右侧)的罩13称为“输入侧罩13”，将位于旋转轴Ax1的输出侧(在图7中为左侧)的罩14称为“输出侧罩14”。在本实施方式中，一对罩 13、14的材质为不锈钢、铸铁、机械结构用碳素钢或铬钼钢等金属、或者对其实施了热处理的金属。The gear device 1A of this embodiment further includes a pair of covers 13 and 14 mounted on both sides of the brackets 18 and 19 in the axial direction. When the pair of covers 13 and 14 are distinguished from each other, the cover 13 located on the input side (right side in FIG. 7 ) of the rotation axis Ax1 is referred to as the "input side cover 13", and the cover 14 located on the output side (left side in FIG. 7 ) of the rotation axis Ax1 is referred to as the "output side cover 14". In this embodiment, the pair of covers The material of 13 and 14 is metal such as stainless steel, cast iron, carbon steel for machine structure or chrome-molybdenum steel, or a metal subjected to heat treatment.
输入侧罩13形成为以旋转轴Ax1为中心的圆盘状。此处，输入侧罩13的至少外周面在俯视观察下(从轴向的一方观察)以旋转轴Ax1为中心的正圆。输入侧罩13的外径比输入侧支架18的外径小一圈。输入侧罩13相对于输入侧支架18从外侧、也就是从输入侧支架18观察时与行星齿轮3相反的一侧(在图7中为右侧)安装。The input side cover 13 is formed in a disk shape with the rotation axis Ax1 as the center. Here, at least the outer peripheral surface of the input side cover 13 is a perfect circle with the rotation axis Ax1 as the center when viewed from above (viewed from one axial direction). The outer diameter of the input side cover 13 is one circle smaller than the outer diameter of the input side bracket 18. The input side cover 13 is mounted on the input side bracket 18 from the outside, that is, on the side opposite to the planetary gear 3 when viewed from the input side bracket 18 (the right side in FIG. 7 ).
输出侧罩14形成为以旋转轴Ax1为中心的圆盘状。此处，输出侧罩14的至少外周面在俯视观察下(从轴向的一方观察)以旋转轴Ax1为中心的正圆。输出侧罩14的外径比输出侧支架19的外径小一圈。输出侧罩14相对于输出侧支架19从外侧、也就是从输出侧支架19观察时与行星齿轮3相反的一侧(在图7中为左侧)安装。The output side cover 14 is formed in a disk shape with the rotation axis Ax1 as the center. Here, at least the outer peripheral surface of the output side cover 14 is a perfect circle with the rotation axis Ax1 as the center when viewed from above (viewed from one side in the axial direction). The outer diameter of the output side cover 14 is one circle smaller than the outer diameter of the output side bracket 19. The output side cover 14 is mounted relative to the output side bracket 19 from the outside, that is, on the side opposite to the planetary gear 3 when viewed from the output side bracket 19 (the left side in FIG. 7).
此处，一对罩13、14以能够拆卸的方式安装于一对支架18、19。也就是说，输入侧罩13以能够拆卸的方式安装于输入侧支架18，输出侧罩14以能够拆卸的方式安装于输出侧支架19。在本实施方式中，作为一例，各罩13、14通过多个固定螺栓142(参照图7)安装于各支架18、19。因此，通过卸下多个固定螺栓142，能够从各支架18、19拆卸各罩13、14。Here, a pair of covers 13 and 14 are detachably mounted on a pair of brackets 18 and 19. That is, the input side cover 13 is detachably mounted on the input side bracket 18, and the output side cover 14 is detachably mounted on the output side bracket 19. In the present embodiment, as an example, each cover 13 and 14 is mounted on each bracket 18 and 19 by a plurality of fixing bolts 142 (see FIG. 7). Therefore, by removing the plurality of fixing bolts 142, each cover 13 and 14 can be removed from each bracket 18 and 19.
此处，在一对罩13、14中的输出侧罩14处，与设置于输出侧支架19的多个安装孔194(参照图7)对应地设置有多个透孔141。即，在输出侧支架19设置有用于固定对象构件的多个安装孔194(内螺纹)。因此，在安装于输出侧支架19的外侧的输出侧罩14处，在与这些多个安装孔194对应的位置形成有多个透孔141。Here, in the output side cover 14 of the pair of covers 13 and 14, a plurality of through holes 141 are provided corresponding to the plurality of mounting holes 194 (refer to FIG. 7 ) provided in the output side bracket 19. That is, a plurality of mounting holes 194 (internal threads) for fixing the target member are provided in the output side bracket 19. Therefore, in the output side cover 14 installed on the outside of the output side bracket 19, a plurality of through holes 141 are formed at positions corresponding to the plurality of mounting holes 194.
另一方面，穿过各曲轴7A、7B、7C的轴孔131(参照图7)仅设置于一对罩13、14中的输入侧罩13。也就是说，在输入侧罩13与多个曲轴7A、7B、7C对应地设置有轴孔131。在各轴孔131***有各曲轴7A、7B、7C的轴心部71。此处，为了避免轴心部71与轴孔131的内周面接触，各轴孔131的内径设定为比轴心部71的外径大一圈。 On the other hand, the shaft hole 131 (refer to FIG. 7 ) through which each crankshaft 7A, 7B, 7C passes is provided only in the input side cover 13 of the pair of covers 13 and 14. That is, the shaft hole 131 is provided in the input side cover 13 corresponding to the plurality of crankshafts 7A, 7B, 7C. The shaft center portion 71 of each crankshaft 7A, 7B, 7C is inserted into each shaft hole 131. Here, in order to prevent the shaft center portion 71 from contacting the inner peripheral surface of the shaft hole 131, the inner diameter of each shaft hole 131 is set to be one circle larger than the outer diameter of the shaft center portion 71.
此处，本实施方式的齿轮装置1A包括限制各曲轴7A、7B、7C的轴向的移动的限制结构70。也就是说，在本实施方式的齿轮装置1A中，限制结构70限制曲轴7A、7B、7C的轴向的移动。本公开所说的“轴向”是指沿着旋转轴Ax1的方向、也就是沿着曲轴7A、7B、7C的轴心Ax2的方向，特别是与曲轴7A、7B、7C的轴心Ax2平行的方向(推力方向)。另外，本公开所述的“限制移动”是指对移动施加某种限制，不仅完全禁止移动，还包含限制移动范围或使移动难以移动等。也就是说，在本实施方式中，通过设置限制结构70，在沿着曲轴7A、7B、7C的轴心Ax2的轴向上，限制曲轴7A、7B、7C的移动。Here, the gear device 1A of the present embodiment includes a limiting structure 70 that limits the axial movement of each crankshaft 7A, 7B, 7C. That is, in the gear device 1A of the present embodiment, the limiting structure 70 limits the axial movement of the crankshafts 7A, 7B, 7C. The "axial direction" mentioned in the present disclosure refers to the direction along the rotation axis Ax1, that is, the direction along the axis Ax2 of the crankshafts 7A, 7B, 7C, especially the direction parallel to the axis Ax2 of the crankshafts 7A, 7B, 7C (thrust direction). In addition, the "limited movement" mentioned in the present disclosure refers to imposing certain restrictions on movement, which not only completely prohibits movement, but also includes limiting the range of movement or making it difficult to move. That is, in the present embodiment, by setting the limiting structure 70, the movement of the crankshafts 7A, 7B, 7C is limited in the axial direction along the axis Ax2 of the crankshafts 7A, 7B, 7C.
在本实施方式中，作为一例，限制结构70在轴向的一侧(旋转轴Ax1的输入侧)和另一侧(旋转轴Ax1的输出侧)的两侧，禁止曲轴7A、7B、7C的移动。即，在图7的例子中，限制结构70相对于一对支架18、19禁止曲轴7A、7B、7C向图中右侧的移动和向图中左侧的移动的任一个。由此，轴向上的曲轴7A、7B、7C的位置(相对于一对支架18、19)被定位在规定位置。In this embodiment, as an example, the restriction structure 70 prohibits the movement of the crankshafts 7A, 7B, and 7C on both sides of one side (the input side of the rotation axis Ax1) and the other side (the output side of the rotation axis Ax1) in the axial direction. That is, in the example of FIG. 7 , the restriction structure 70 prohibits the movement of the crankshafts 7A, 7B, and 7C to the right side in the figure and to the left side in the figure relative to the pair of brackets 18 and 19. As a result, the positions of the crankshafts 7A, 7B, and 7C in the axial direction (relative to the pair of brackets 18 and 19) are positioned at a predetermined position.
在本实施方式中，限制结构70包含安装于一对支架18、19的轴向的两侧的一对罩13、14。总之，齿轮装置1A使用安装于输入侧支架18的输入侧罩13和安装于输出侧支架19的输出侧罩14来限制各曲轴7A、7B、7C的向轴向的一侧和另一侧的移动。In the present embodiment, the limiting structure 70 includes a pair of covers 13 and 14 mounted on both sides of the pair of brackets 18 and 19 in the axial direction. In short, the gear device 1A uses the input side cover 13 mounted on the input side bracket 18 and the output side cover 14 mounted on the output side bracket 19 to limit the movement of each crankshaft 7A, 7B, 7C to one side and the other side in the axial direction.
具体而言，输入侧罩13因受到从曲轴7A、7B、7C朝向轴向的一侧(在图7中为右方)作用的力而限制曲轴7A、7B、7C向轴向的一侧的移动。另一方面，输出侧罩14因受到从曲轴7A、7B、7C朝向轴向的另一侧作用的力而限制曲轴7A、7B、7C向轴向的另一侧的移动。Specifically, the input side cover 13 receives a force from the crankshafts 7A, 7B, 7C to one axial side (rightward in FIG. 7 ), thereby restricting the movement of the crankshafts 7A, 7B, 7C to one axial side. On the other hand, the output side cover 14 receives a force from the crankshafts 7A, 7B, 7C to the other axial side, thereby restricting the movement of the crankshafts 7A, 7B, 7C to the other axial side.
更详细地说，通过使曲轴7A、7B、7C的朝向旋转轴Ax1的输入侧(在图8中为右侧)的台阶部与输入侧罩13的朝向旋转轴Ax1的输出侧(在图7中为左侧)的表面的轴孔131的周围接触，从而限制曲轴7A、7B、7C向轴向的一侧(在图7中为右侧)的移动。另外，通过使曲轴7A、7B、7C的朝向旋转轴Ax1的输出侧(在图7中为左侧)的端面与输出侧罩14的朝向旋转轴Ax1的输入侧(在图7中为右侧)的表面接触，从而限制曲轴7A、7B、7C向轴向的 另一侧(在图7中为左侧)的移动。More specifically, the step portion of the crankshafts 7A, 7B, 7C on the input side (right side in FIG. 8 ) of the rotation axis Ax1 is brought into contact with the periphery of the shaft hole 131 of the surface of the input side cover 13 on the output side (left side in FIG. 7 ) of the rotation axis Ax1, thereby limiting the movement of the crankshafts 7A, 7B, 7C in the axial direction to one side (right side in FIG. 7 ). In addition, the end surface of the crankshafts 7A, 7B, 7C on the output side (left side in FIG. 7 ) of the rotation axis Ax1 is brought into contact with the surface of the output side cover 14 on the input side (right side in FIG. 7 ) of the rotation axis Ax1, thereby limiting the movement of the crankshafts 7A, 7B, 7C in the axial direction. Movement on the other side (left side in FIG. 7 ).
然而，如图7和图8所示，本实施方式的齿轮装置1A的内齿齿轮2的齿轮主体22具有能够弹性变形的弹性变形部24。弹性变形部24设于齿轮主体22中的、至少形成有多个内周槽223的部位。此处，多个内周槽223由于形成于齿轮主体22的内周面221的圆周方向的整个区域，所以弹性变形部24也设于齿轮主体22的圆周方向的整个区域。However, as shown in Fig. 7 and Fig. 8, the gear body 22 of the internal gear 2 of the gear device 1A of the present embodiment has an elastically deformable elastically deformable portion 24. The elastically deformable portion 24 is provided at a portion of the gear body 22 where at least a plurality of inner peripheral grooves 223 are formed. Here, since the plurality of inner peripheral grooves 223 are formed over the entire area in the circumferential direction of the inner peripheral surface 221 of the gear body 22, the elastically deformable portion 24 is also provided over the entire area in the circumferential direction of the gear body 22.
本公开所说的“弹性”是指通过外力而变形(弹性变形)，且在解除该外力时恢复到原来的形状的性质。由此，弹性变形部24例如从另一部件受到向外(也就是朝向与旋转轴Ax1相反的一侧)的外力时，以使齿轮主体22直径扩大的方式产生弹性变形，并且使向内(也就是朝向旋转轴Ax1侧)的反作用力(弹性力)作用于该另一部件。The "elasticity" mentioned in the present disclosure refers to the property of being deformed (elastic deformation) by an external force and returning to the original shape when the external force is removed. Thus, when the elastic deformation portion 24 receives an external force outward (that is, toward the side opposite to the rotation axis Ax1) from another component, for example, the gear body 22 is elastically deformed in such a way that the diameter is expanded, and a reaction force (elastic force) inward (that is, toward the rotation axis Ax1 side) is applied to the other component.
此处，弹性变形部24使朝向齿轮主体22的内侧、也就是旋转轴Ax1靠压的方向的力F0作用于构成内齿21的多个销23。也就是说，弹性变形部24至少可在齿轮主体22的径向上产生弹性变形，至少从内齿21中的成为与外齿31的啮合部位的1个以上的销23受到使齿轮主体22直径扩大的方向的力而产生弹性变形。因此，弹性变形部24作为对从1个以上的销23受到的力的反作用力，使向外齿31靠压的方向的力F0作用于该1个以上的销23。结果是，至少在内齿21与外齿31的啮合部位处，构成内齿21的销23通过齿轮主体22的弹性变形部24而被靠压于外齿31。Here, the elastic deformation part 24 causes a force F0 in a direction of pressing toward the inner side of the gear body 22, that is, the rotation axis Ax1, to act on the plurality of pins 23 constituting the internal teeth 21. That is, the elastic deformation part 24 can be elastically deformed in at least the radial direction of the gear body 22, and at least one or more pins 23 of the internal teeth 21 that become the meshing part with the external teeth 31 receive a force in a direction of expanding the diameter of the gear body 22 and are elastically deformed. Therefore, the elastic deformation part 24 causes a force F0 in a direction of pressing toward the external teeth 31 to act on the one or more pins 23 as a reaction force to the force received from the one or more pins 23. As a result, at least at the meshing part between the internal teeth 21 and the external teeth 31, the pins 23 constituting the internal teeth 21 are pressed against the external teeth 31 through the elastic deformation part 24 of the gear body 22.
总之，本实施方式的齿轮装置1A包括内齿齿轮2和行星齿轮3。内齿齿轮2具有环状的齿轮主体22和多个销23。多个销23以能够自转的状态保持于在齿轮主体22的内周面221形成的多个内周槽223，并构成内齿21。行星齿轮3具有与内齿21局部性地啮合的外齿31。齿轮装置1A通过使行星齿轮3摆动，从而使行星齿轮3相对于内齿齿轮2相对旋转。齿轮主体22在至少形成有多个内周槽223的部位具有能够弹性变形的弹性变形部24。In summary, the gear device 1A of the present embodiment includes an internal gear 2 and a planetary gear 3. The internal gear 2 has an annular gear body 22 and a plurality of pins 23. The plurality of pins 23 are held in a plurality of inner peripheral grooves 223 formed on the inner peripheral surface 221 of the gear body 22 in a state capable of self-rotation, and constitute the internal teeth 21. The planetary gear 3 has an outer tooth 31 partially meshed with the internal teeth 21. The gear device 1A causes the planetary gear 3 to rotate relative to the internal gear 2 by swinging the planetary gear 3. The gear body 22 has an elastically deformable elastically deformable portion 24 at least at a portion where the plurality of inner peripheral grooves 223 are formed.
根据上述结构，至少在内齿21中的与外齿31的啮合部位处，被保持于内周槽223的销23通过来自齿轮主体22的弹性变形部24的弹性力而被靠压于外 齿31。因此，由多个销23构成的内齿21与外齿31之间的间隙(游隙)被填埋，从而齿隙减少。由此，在本实施方式的齿轮装置1A中，具有以下优点：即使在内齿21与外齿31的啮合部位处内齿21与外齿31之间的间隙扩展，也容易抑制齿隙的增大。According to the above structure, at least at the meshing portion of the inner teeth 21 with the outer teeth 31, the pin 23 held in the inner peripheral groove 223 is pressed against the outer teeth 31 by the elastic force of the elastic deformation portion 24 of the gear body 22. Therefore, the gap (play) between the internal teeth 21 and the external teeth 31 formed by the plurality of pins 23 is filled, thereby reducing the backlash. Thus, in the gear device 1A of this embodiment, there is an advantage that even if the gap between the internal teeth 21 and the external teeth 31 expands at the meshing portion of the internal teeth 21 and the external teeth 31, it is easy to suppress the increase of the backlash.
更详细地说，在一般的齿轮装置中，特别是因长期的使用或者高负荷下的使用等使用环境，有时在行星齿轮3的外齿31产生磨损。当在外齿31产生磨损时，在内齿21与外齿31的啮合部位处，内齿21与外齿31之间的间隙渐渐扩展，可能使得齿隙增大。也就是说，即使在齿轮装置的使用开始时(制造时)齿隙处于所期望的范围，随着时间的推移，齿隙增大，有时会偏离所期望的范围。In more detail, in a general gear device, in particular, due to long-term use or use under high load, the outer teeth 31 of the planetary gear 3 may be worn. When the outer teeth 31 are worn, the gap between the inner teeth 21 and the outer teeth 31 gradually expands at the meshing portion of the inner teeth 21 and the outer teeth 31, which may increase the backlash. In other words, even if the backlash is within the desired range at the beginning of use of the gear device (at the time of manufacturing), the backlash increases over time and sometimes deviates from the desired range.
另外，为了将使用开始时(制造时)的间隙抑制得小，也考虑采用外齿31以比较大的力靠压内齿21(多个销23)的设计，但是在该情况下，外齿31更容易磨损，并且齿轮装置的动力传递效率也下降。进一步，为了将齿隙抑制得小，还存在要求严格的部件的尺寸精度及组装精度的问题。除此之外，在内接合行星齿轮装置中，不进行齿形修整的状态在理论上性能良好，但是因部件的尺寸(加工)误差、组装误差或变形等影响而需要齿形修正，并且为了齿形修整还需要很大的技术诀窍和经验。综上所述，在内接合行星齿轮装置中，将齿隙抑制得小是不容易的，进一步，考虑到随着时间的推移的外齿31的磨损而抑制齿隙的增大也是困难的。In addition, in order to reduce the backlash at the beginning of use (during manufacturing), it is also considered to adopt a design in which the outer teeth 31 press against the inner teeth 21 (multiple pins 23) with a relatively large force, but in this case, the outer teeth 31 are more easily worn and the power transmission efficiency of the gear device is also reduced. Furthermore, in order to reduce the backlash, there is also the problem of requiring strict dimensional accuracy and assembly accuracy of the components. In addition, in the internally engaged planetary gear device, the state without tooth profile trimming is theoretically good, but tooth profile correction is required due to the influence of dimensional (machining) errors, assembly errors or deformation of the components, and great technical know-how and experience are required for tooth profile trimming. In summary, in the internally engaged planetary gear device, it is not easy to reduce the backlash, and further, it is difficult to suppress the increase of the backlash considering the wear of the outer teeth 31 over time.
本实施方式的齿轮装置1A通过在齿轮主体22的至少形成有多个内周槽223的部位具有弹性变形部24，从而可以解决这样的困难的课题。即，在齿轮装置1A中，通过使轮主体22的弹性变形部24仿照行星齿轮3积极地弹性变形，从而减小行星齿轮3的外齿31与内齿齿轮2的内齿21之间的间隙，将齿隙抑制得小。而且，通过弹性变形部24产生弹性变形，能够追随因磨损而引起的行星齿轮3的外齿31的尺寸变化，因此即使外齿31随着时间的推移而磨损，也能够抑制齿隙的增大。The gear device 1A of this embodiment can solve such a difficult problem by having an elastic deformation portion 24 at least at a portion where a plurality of inner peripheral grooves 223 are formed on the gear body 22. That is, in the gear device 1A, the gap between the outer teeth 31 of the planetary gear 3 and the inner teeth 21 of the internal gear 2 is reduced by actively elastically deforming the elastic deformation portion 24 of the gear body 22 in imitation of the planetary gear 3, thereby suppressing the backlash to be small. Moreover, since the elastic deformation portion 24 is elastically deformed, it is possible to follow the dimensional change of the outer teeth 31 of the planetary gear 3 caused by wear, so that even if the outer teeth 31 are worn over time, the increase of the backlash can be suppressed.
特别是，在齿轮装置1A应用于后述的机器人用关节装置200(参照图11) 的情况下，当齿隙变大时，直接关系到臂等的前端部的摇晃(位置偏离)及空转的增大，而通过抑制齿隙的增大，能够提高机器人的控制精度。In particular, the gear device 1A is applied to a robot joint device 200 (see FIG. 11 ) described later. In the case of a large backlash, it is directly related to the increase of shaking (position deviation) and idling of the front end of the arm, etc., and by suppressing the increase of the backlash, the control accuracy of the robot can be improved.
具体而言，在本实施方式中，如图8和图9所示，弹性变形部24包含通过在齿轮主体22的外周面遍及周向地形成有外周槽25而被薄壁化了的部位。也就是说，在齿轮主体22中的外周面中的至少内齿21的齿向方向(与旋转轴Ax1平行的方向)的中央部分遍及周向的整周地形成外周槽25。由此，在齿轮主体22中的内齿21的齿向方向的中央部分形成有弹性变形部24，该弹性变形部24至少与齿轮主体22中的内齿21的齿向方向的两侧部分相比薄壁化、也就是厚度设定得小。Specifically, in the present embodiment, as shown in FIG8 and FIG9, the elastic deformation portion 24 includes a portion thinned by forming an outer peripheral groove 25 throughout the circumferential direction on the outer peripheral surface of the gear body 22. That is, the outer peripheral groove 25 is formed throughout the entire circumference of at least the central portion of the tooth direction (direction parallel to the rotation axis Ax1) of the inner teeth 21 in the outer peripheral surface of the gear body 22. Thus, the elastic deformation portion 24 is formed in the central portion of the tooth direction of the inner teeth 21 in the gear body 22, and the elastic deformation portion 24 is thinned, that is, the thickness is set smaller than at least the two side portions of the tooth direction of the inner teeth 21 in the gear body 22.
此处，如图8所示，外周槽25在内齿21的齿向方向上具有收纳在内周槽223的宽度尺寸内的宽度尺寸。也就是说，弹性变形部24仅形成于齿轮主体22中的在内齿21的齿向方向上形成有内周槽223的范围内。进一步，外周槽25以距齿轮主体22的外周面的深度越大内齿21的齿向方向上的宽度尺寸越小的方式形成为剖面梯形状。换言之，外周槽25随着靠近其开口而宽度尺寸变大。Here, as shown in FIG. 8 , the outer peripheral groove 25 has a width dimension in the tooth direction of the internal teeth 21 that is accommodated within the width dimension of the inner peripheral groove 223. That is, the elastic deformation portion 24 is formed only in the range of the gear body 22 where the inner peripheral groove 223 is formed in the tooth direction of the internal teeth 21. Further, the outer peripheral groove 25 is formed in a cross-sectional trapezoidal shape in such a manner that the greater the depth from the outer peripheral surface of the gear body 22, the smaller the width dimension in the tooth direction of the internal teeth 21. In other words, the width dimension of the outer peripheral groove 25 increases as it approaches its opening.
根据这样的结构，在齿轮主体22形成有隔膜结构(膜结构)的弹性变形部24。根据隔膜结构的齿轮主体22，尽管弹性变形变得容易，却也能够抑制应力集中的发生。According to such a structure, the elastic deformation part 24 of a diaphragm structure (film structure) is formed in the gear body 22. According to the gear body 22 of a diaphragm structure, although elastic deformation becomes easy, it is possible to suppress the occurrence of stress concentration.
另外，本实施方式的齿轮装置1A还包括环状的支承框9。齿轮主体22在支承框9的内侧处固定于支承框9。并且，在弹性变形部2与支承框9之间设置有间隙。总之，齿轮主体22在嵌入比齿轮主体22大一圈的环状的支承框9的状态下，以外周槽25的开口被支承框9封闭的方式固定于支承框9。在该状态下，在弹性变形部24的弹性变形部24与支承框9的内周面之间形成有由外周槽25构成的间隙。此处，支承框9至少与弹性变形部24相比具有足够高的刚性。在本实施方式中，固定用的多个固定孔222形成于支承框9来代替形成于齿轮主体22。In addition, the gear device 1A of the present embodiment further includes an annular support frame 9. The gear body 22 is fixed to the support frame 9 at the inner side of the support frame 9. And, a gap is provided between the elastic deformation portion 2 and the support frame 9. In short, the gear body 22 is fixed to the support frame 9 in a state where the opening of the outer peripheral groove 25 is closed by the support frame 9 while being embedded in the annular support frame 9 which is one circle larger than the gear body 22. In this state, a gap formed by the outer peripheral groove 25 is formed between the elastic deformation portion 24 of the elastic deformation portion 24 and the inner peripheral surface of the support frame 9. Here, the support frame 9 has sufficiently high rigidity at least compared with the elastic deformation portion 24. In the present embodiment, a plurality of fixing holes 222 for fixing are formed in the support frame 9 instead of being formed in the gear body 22.
因此，通过设置弹性变形部24而下降的齿轮主体22的刚性能够由支承框9确保。通过设置这样的支承框9，并通过(使用多个固定孔222)将支承框9 固定于另一构件，尽管在齿轮主体22设置弹性变形部24，但齿轮主体22也容易固定于另一构件。Therefore, the rigidity of the gear body 22 which is reduced by providing the elastic deformation portion 24 can be ensured by the support frame 9. By providing such a support frame 9 and fixing the support frame 9 (using a plurality of fixing holes 222), Fixed to Another Member: Although the gear body 22 is provided with the elastic deformation portion 24 , the gear body 22 can be easily fixed to another member.
进一步，如图8和图9所示，齿轮主体22在内齿21的齿向方向上的从弹性变形部24观察至少一侧具有刚性比弹性变形部24高的加强部26。在本实施方式中，外周槽25的宽度方向(内齿21的齿向方向)的两侧部分具有比弹性变形部24大的厚度，作为加强部26发挥功能。通过设置这样的加强部26，尽管能够使弹性变形部24弹性变形，但也容易对齿轮主体22确保所期望的刚性。Furthermore, as shown in FIG8 and FIG9, the gear body 22 has a reinforcing portion 26 having a higher rigidity than the elastic deformation portion 24 on at least one side viewed from the elastic deformation portion 24 in the tooth direction of the internal teeth 21. In the present embodiment, the two side portions of the width direction (tooth direction of the internal teeth 21) of the outer peripheral groove 25 have a thickness greater than that of the elastic deformation portion 24, and function as the reinforcing portion 26. By providing such a reinforcing portion 26, it is easy to ensure the desired rigidity of the gear body 22 even though the elastic deformation portion 24 can be elastically deformed.
另外，多个内周槽223各自的内径比多个销23各自的外径大。即，如图10所示，内周槽223的剖面形状与圆柱状的销23相符地形成为圆弧状，且该圆弧的半径r2比销23的半径r1大(r1＜r2)。换言之，内周槽223的内周的曲率半径r2设定为比销23的外周的曲率半径r1大。因此，例如，即使弹性变形部24变形而内周槽223的内径稍稍变动，内周槽223的内径也难以低于销23的外径，能够抑制内周槽223的开口周缘咬入销23的外周面。In addition, the inner diameter of each of the plurality of inner circumferential grooves 223 is larger than the outer diameter of each of the plurality of pins 23. That is, as shown in FIG. 10 , the cross-sectional shape of the inner circumferential groove 223 is formed into an arc shape in accordance with the cylindrical pin 23, and the radius r2 of the arc is larger than the radius r1 of the pin 23 (r1＜r2). In other words, the curvature radius r2 of the inner circumference of the inner circumferential groove 223 is set to be larger than the curvature radius r1 of the outer circumference of the pin 23. Therefore, for example, even if the elastic deformation portion 24 is deformed and the inner diameter of the inner circumferential groove 223 changes slightly, the inner diameter of the inner circumferential groove 223 is unlikely to be lower than the outer diameter of the pin 23, and the opening periphery of the inner circumferential groove 223 can be prevented from biting into the outer circumferential surface of the pin 23.
然而，弹性变形部24只要至少在内齿21中的与外齿31的啮合部位处具有将被保持于内周槽223的销23向外齿31靠压的弹性即可，不限于通过外周槽25而被薄壁化了的结构。也就是说，弹性变形部24具有因外力而变形、并且在解除该外力时恢复到原来的形状的性质(弹性)，通过弹性力将销23靠压于外齿31。弹性变形部24优选由具有180GPa以下的杨氏模量的材质构成。However, the elastic deformation part 24 only needs to have elasticity to press the pin 23 held in the inner peripheral groove 223 against the outer teeth 31 at least at the meshing part of the inner teeth 21 with the outer teeth 31, and is not limited to the structure that is thinned by the outer peripheral groove 25. In other words, the elastic deformation part 24 has the property (elasticity) of being deformed by external force and returning to the original shape when the external force is released, and presses the pin 23 against the outer teeth 31 by the elastic force. The elastic deformation part 24 is preferably composed of a material having a Young's modulus of 180 GPa or less.
如图11所示，本实施方式的齿轮装置1A与第一构件201及第二构件202一起构成机器人用关节装置200。换言之，本实施方式的机器人用关节装置200包括齿轮装置1A、第一构件201和第二构件202。第一构件201由齿轮主体22固定。第二构件202伴随着行星齿轮3相对于内齿齿轮2的相对旋转而相对于第一构件201相对。图11是机器人用关节装置200的概略剖视图。另外，在图11中，示意性地示出第一构件201、第二构件202和驱动源101。As shown in FIG11 , the gear device 1A of the present embodiment together with the first member 201 and the second member 202 constitute a joint device 200 for a robot. In other words, the joint device 200 for a robot of the present embodiment includes the gear device 1A, the first member 201 and the second member 202. The first member 201 is fixed by the gear body 22. The second member 202 is relative to the first member 201 as the planetary gear 3 rotates relative to the internal gear 2. FIG11 is a schematic cross-sectional view of the joint device 200 for a robot. In addition, FIG11 schematically shows the first member 201, the second member 202 and the drive source 101.
如此构成的机器人用关节装置200通过将第一构件201与第二构件202以旋转轴Ax1为中心相对地旋转，从而作为关节装置发挥功能。此处，通过由驱动源101驱动齿轮装置1A的输入轴500，从而第一构件201与第二构件202相 对旋转。此时，驱动源101所产生的旋转(输入旋转)在齿轮装置1A中以比较高的减速比被减速，而以比较高的力矩驱动第一构件201或第二构件202。也就是说，由齿轮装置1A连结的第一构件201与第二构件202以旋转轴Ax1为中心能够进行屈伸动作。The robot joint device 200 constructed in this way functions as a joint device by relatively rotating the first member 201 and the second member 202 around the rotation axis Ax1. Here, the input shaft 500 of the gear device 1A is driven by the drive source 101, so that the first member 201 and the second member 202 are relatively rotated. At this time, the rotation (input rotation) generated by the driving source 101 is decelerated at a relatively high reduction ratio in the gear device 1A, and the first member 201 or the second member 202 is driven with a relatively high torque. In other words, the first member 201 and the second member 202 connected by the gear device 1A can bend and stretch around the rotation axis Ax1.
机器人用关节装置200例如用于水平多关节机器人(关节型机器人)这样的机器人。进一步，机器人用关节装置200并不限于水平多关节机器人，例如，也可以用于除水平多关节机器人以外的产业用机器人、或者除产业用以外的机器人等。另外，本实施方式的齿轮装置1A并不局限于机器人用关节装置200，例如，作为轮毂电机等车轮装置，也可以用于无人搬送车(AGV：Automated Guided Vehicle)等车辆。The robot joint device 200 is used for a robot such as a horizontal multi-joint robot (articular robot). Furthermore, the robot joint device 200 is not limited to a horizontal multi-joint robot, and for example, it can also be used for an industrial robot other than a horizontal multi-joint robot, or a robot other than industrial robots. In addition, the gear device 1A of this embodiment is not limited to the robot joint device 200, and for example, as a wheel device such as a hub motor, it can also be used in vehicles such as unmanned guided vehicles (AGV: Automated Guided Vehicle).
＜变形例＞＜Modification＞
实施方式一只不过是本公开的各种实施方式的一个。实施方式一只要能够实现本公开的目的，就可以根据设计等进行各种变更。另外，本公开中所参照的附图均为示意图，图中的各结构要素的大小和厚度各自的比不一定限于反映实际的尺寸比。以下，列举实施方式一的变形例。以下说明的变形例可以适当组合适用。Implementation method 1 is only one of various implementation methods of the present disclosure. Implementation method 1 can be modified in various ways according to the design, etc., as long as it can achieve the purpose of the present disclosure. In addition, the drawings referred to in the present disclosure are all schematic diagrams, and the size and thickness ratios of the various structural elements in the drawings are not necessarily limited to reflect the actual dimensional ratios. The following lists the modified examples of implementation method 1. The modified examples described below can be appropriately combined and applied.
曲轴7A、7B、7C的个数不限于“3”，也可以是2或4以上。进一步，如果曲轴仅为1个，则不是分配型，而是实现旋转轴Ax1与曲轴的轴心Ax2一致的偏心摆动型的内啮合行星齿轮装置。在该情况下，通过驱动曲轴使行星齿轮3摆动，并能够使一对支架18、19以旋转轴Ax1为中心相对于齿轮主体22相对旋转。The number of crankshafts 7A, 7B, and 7C is not limited to "3", and may be 2 or 4 or more. Furthermore, if there is only one crankshaft, it is not a distributed type, but an eccentric swing type internal meshing planetary gear device that realizes the coincidence of the rotation axis Ax1 and the axis Ax2 of the crankshaft. In this case, the planetary gear 3 is swung by driving the crankshaft, and the pair of brackets 18 and 19 can be relatively rotated with respect to the gear body 22 around the rotation axis Ax1.
另外，在实施方式一中，例示了行星齿轮3为2个的类型的齿轮装置1A，但是齿轮装置1A也可以包括3个以上行星齿轮3。例如，在齿轮装置1A包括三个行星齿轮3的情况下，优选这三个行星齿轮3绕着旋转轴Ax1以120度的位相差配置。另外，齿轮装置1A也可以仅包括一个行星齿轮3。或者，在齿轮装置1A包括三个行星齿轮3的情况下，也可以这些三个行星齿轮3中的两个行星齿轮3为相同位相，剩余的一个行星齿轮3绕着旋转轴Ax1以180度的位 相差配置。In the first embodiment, a gear device 1A having two planetary gears 3 is illustrated, but the gear device 1A may include more than three planetary gears 3. For example, when the gear device 1A includes three planetary gears 3, it is preferred that the three planetary gears 3 are arranged with a phase difference of 120 degrees around the rotation axis Ax1. In addition, the gear device 1A may include only one planetary gear 3. Alternatively, when the gear device 1A includes three planetary gears 3, two of the three planetary gears 3 may be in the same phase, and the remaining one planetary gear 3 may be arranged with a phase difference of 180 degrees around the rotation axis Ax1. Phase difference configuration.
另外，轴承构件6既可以是交叉滚子轴承，也可以是深沟球轴承或四点接触球轴承等。In addition, the bearing member 6 may be a crossed roller bearing, a deep groove ball bearing, a four-point contact ball bearing, or the like.
另外，实施方式一所说明的输入齿轮501的齿数、曲轴齿轮502A、502B、502C的齿数、销23的数量(内齿21的齿数)和外齿31的齿数等只不过为一例，可以适当变更。The number of teeth of the input gear 501, the number of teeth of the crank gears 502A, 502B, 502C, the number of pins 23 (the number of teeth of the internal teeth 21), and the number of teeth of the external teeth 31 described in the first embodiment are merely examples and may be changed as appropriate.
另外，偏心体轴承5并不局限于滚子球轴承，例如，也可以为深沟球轴承或角接触球轴承等。In addition, the eccentric bearing 5 is not limited to a roller ball bearing, and may be, for example, a deep groove ball bearing or an angular contact ball bearing.
另外，齿轮装置1A的各结构要素的材质并不限于金属，例如，可以为工序塑料等树脂。In addition, the material of each component of the gear device 1A is not limited to metal, and may be, for example, resin such as process plastic.
另外，齿轮装置1A只要是能够将轴承构件6的内圈61与外圈62之间的相对的旋转作为输出取出即可，并不限于将内圈61(输入侧支架18和输出侧支架19)的旋转力作为输出取出的结构。例如，也可以将相对于内圈61相对地旋转的外圈62(壳体10)的旋转力作为输出取出。In addition, the gear device 1A is not limited to a structure in which the rotational force of the inner ring 61 (input side bracket 18 and output side bracket 19) is taken out as output, as long as the relative rotation between the inner ring 61 and the outer ring 62 of the bearing member 6 can be taken out as output. For example, the rotational force of the outer ring 62 (housing 10) rotating relative to the inner ring 61 can also be taken out as output.
另外，在实施方式一中，曲轴7A、7B、7C的旋转轴Ax1的输出侧的端面与输出侧罩14直接接触，但不限于该结构，也可以在端面与输出侧罩14之间例如配置垫片构件等板状部件。在该情况下，在安装输出侧罩14时，通过调节板状部件的厚度(和/或片数)，能够在轴向上调节端面与输出侧罩14之间的间隙，能够调节曲轴7A、7B、7C的轴向上的“游隙”。进一步，板状部件作为降低端面与输出侧罩14之间的摩擦的轨道圈(轨道盘)发挥功能。In addition, in the first embodiment, the end face of the output side of the rotating axis Ax1 of the crankshaft 7A, 7B, 7C is in direct contact with the output side cover 14, but it is not limited to this structure, and a plate-like component such as a gasket member may be arranged between the end face and the output side cover 14. In this case, when the output side cover 14 is installed, by adjusting the thickness (and/or the number of pieces) of the plate-like component, the gap between the end face and the output side cover 14 can be adjusted in the axial direction, and the "play" in the axial direction of the crankshaft 7A, 7B, 7C can be adjusted. Furthermore, the plate-like component functions as a track ring (track disk) that reduces the friction between the end face and the output side cover 14.
另外，润滑剂并不限于润滑油(油液)等液状的物质，可以是润滑脂等凝胶状的物质。The lubricant is not limited to liquid substances such as lubricating oil (oil), and may be a gel-like substance such as grease.
另外，弹性变形部24不限于隔膜结构，例如，也可是包含悬臂结构或板簧结构等适当的结构。In addition, the elastic deformation portion 24 is not limited to the diaphragm structure, and may be an appropriate structure including, for example, a cantilever structure or a leaf spring structure.
另外，在齿轮主体22的外周面形成的外周槽25不限于剖面梯形状，可以采用适当的形状。作为一例，外周槽25的剖面形状既可以如图12A所示为U字状，也可以如图12B所示为矩形状(长方形状)。 In addition, the outer peripheral groove 25 formed on the outer peripheral surface of the gear body 22 is not limited to a cross-sectional trapezoidal shape, and can adopt an appropriate shape. As an example, the cross-sectional shape of the outer peripheral groove 25 can be a U-shape as shown in Figure 12A, or a rectangular shape (rectangular shape) as shown in Figure 12B.
(实施方式二)(Implementation Method 2)
如图13所示，本实施方式的内啮合行星齿轮装置1B(以下，也简称为“齿轮装置1B”)在弹性变形部24设置有检测部91这一方面与实施方式1的齿轮装置1A不同。以下，关于与实施方式一同样的结构，标注相同的附图标记而适当省略说明。图13是与图8(图7的区域Z1的放大图)对应的概略图，用点划线箭头示出电连接关系。As shown in FIG13, the internal meshing planetary gear device 1B of this embodiment (hereinafter, also referred to as "gear device 1B") is different from the gear device 1A of the first embodiment in that the elastic deformation portion 24 is provided with a detection portion 91. Hereinafter, the same reference numerals are used for the same structure as the first embodiment, and the description is appropriately omitted. FIG13 is a schematic diagram corresponding to FIG8 (an enlarged view of the area Z1 of FIG7), and the electrical connection relationship is shown by a dot-dash arrow.
即，在本实施方式中，从设置于弹性变形部24的检测部91通过电信号对信息处理部92输出检测值。检测部91例如包含输出与弹性变形部24的变形量相应的检测值的适当的传感器。作为一例，检测部91是安装于弹性变形部24的应变仪等元件。但是，检测部91不限于应变仪，例如，也可以通过利用静电电容式传感器检测位移量，根据该位移量检测弹性变形部24的变形量。检测部91既可以配置于弹性变形部24的表面(外周面)，也可以至少一部分埋入于弹性变形部24。另外，检测部91只要设置1个以上即可，也可以设置多个检测部91。That is, in the present embodiment, a detection value is outputted from a detection unit 91 provided in the elastic deformation portion 24 to the information processing unit 92 via an electrical signal. The detection unit 91 includes, for example, an appropriate sensor that outputs a detection value corresponding to the deformation amount of the elastic deformation portion 24. As an example, the detection unit 91 is an element such as a strain gauge installed on the elastic deformation portion 24. However, the detection unit 91 is not limited to a strain gauge, and for example, the displacement amount may be detected by using an electrostatic capacitive sensor, and the deformation amount of the elastic deformation portion 24 may be detected based on the displacement amount. The detection unit 91 may be arranged on the surface (outer peripheral surface) of the elastic deformation portion 24, or at least a portion thereof may be buried in the elastic deformation portion 24. In addition, it is sufficient to provide at least one detection unit 91, or a plurality of detection units 91 may be provided.
信息处理部92输入检测部91的检测值(电信号)，并对该检测值进行适当的处理。在本实施方式中，信息处理部92以具有1个以上的处理器的计算机***为主结构，通过1个以上的处理器执行程序，实现作为信息处理部92的功能。信息处理部92以具有CPU(Central Processing Unit)等1个以上的处理器和ROM(Read Only Memory)和RAM(Random Access Memory)等1个以上的存储器的计算机***为主结构，执行各种处理(信息处理)。在本实施方式中，对于信息处理部92而言，例如信息处理部92用于驱动源101(参照图11)的控制。The information processing unit 92 inputs the detection value (electrical signal) of the detection unit 91 and performs appropriate processing on the detection value. In the present embodiment, the information processing unit 92 is mainly structured as a computer system having one or more processors, and executes programs through one or more processors to realize the function of the information processing unit 92. The information processing unit 92 is mainly structured as a computer system having one or more processors such as a CPU (Central Processing Unit) and one or more memories such as a ROM (Read Only Memory) and a RAM (Random Access Memory), and performs various processes (information processing). In the present embodiment, for the information processing unit 92, for example, the information processing unit 92 is used to control the drive source 101 (refer to Figure 11).
信息处理部92基于与弹性变形部24的变形量对应的检测部91的检测值，例如执行推定施加于内齿齿轮2与行星齿轮3之间的扭矩的扭矩推定处理。也就是说，信息处理部92推定为弹性变形部24的变形量越大，扭矩越大。信息处理部92将这样推定的的扭矩反映到例如驱动源101的控制。The information processing unit 92 performs a torque estimation process for estimating the torque applied between the internal gear 2 and the planetary gear 3, for example, based on the detection value of the detection unit 91 corresponding to the deformation amount of the elastic deformation unit 24. That is, the information processing unit 92 estimates that the torque is larger as the deformation amount of the elastic deformation unit 24 is larger. The information processing unit 92 reflects the torque estimated in this way, for example, in the control of the drive source 101.
如以上说明那样，本实施方式的齿轮装置1B还包括检测弹性变形部24的 变形量的检测部91。根据该结构，基于弹性变形部24的变形量，例如能够进行齿轮装置1B的扭矩的推定等。因此，能够将弹性变形部24的变形量反映到例如驱动源101的控制。As described above, the gear device 1B of this embodiment further includes a detection device for detecting the elastic deformation portion 24. Deformation amount detection unit 91 According to this configuration, for example, the torque of the gear device 1B can be estimated based on the deformation amount of the elastic deformation unit 24. Therefore, the deformation amount of the elastic deformation unit 24 can be reflected in the control of the drive source 101, for example.
另外，信息处理部92除了扭矩推定处理之外或者代替扭矩推定处理，例如也可进行外齿31的磨损检测处理等。In addition, the information processing unit 92 may perform, for example, a wear detection process of the external teeth 31 in addition to or instead of the torque estimation process.
实施方式二的结构(包含变形例在内)可以采用与实施方式一所说明的各种结构(包含变形例在内)适当组合。The configuration of the second embodiment (including modifications) can be appropriately combined with the various configurations (including modifications) described in the first embodiment.
(总结)(Summarize)
如以上说明那样，第一形态的内啮合行星齿轮装置(1、1A、1B)包括内齿齿轮(2)和行星齿轮(3)，通过使行星齿轮(3)摆动，使行星齿轮(3)相对于内齿齿轮(2)相对旋转。内齿齿轮(2)具有：环状的齿轮主体(22)；和多个销(23)，以能够自转的状态保持于在齿轮主体(22)的内周面(221)形成的多个内周槽(223)，并构成内齿(21)。行星齿轮(3)具有与内齿(21)局部性地啮合的外齿(31)。齿轮主体(22)在至少形成有多个内周槽(223)的部位具有能够弹性变形的弹性变形部(24)。As described above, the first form of the internally meshing planetary gear device (1, 1A, 1B) includes an internal gear (2) and a planetary gear (3), and the planetary gear (3) is caused to rotate relative to the internal gear (2) by swinging the planetary gear (3). The internal gear (2) has: an annular gear body (22); and a plurality of pins (23) that are held in a plurality of inner peripheral grooves (223) formed on the inner peripheral surface (221) of the gear body (22) in a state capable of self-rotation, and constitute the internal teeth (21). The planetary gear (3) has external teeth (31) that partially mesh with the internal teeth (21). The gear body (22) has an elastically deformable elastic portion (24) that can be elastically deformed at least at a portion where the plurality of inner peripheral grooves (223) are formed.
根据该形态，至少在内齿(21)中的与外齿(31)的啮合部位处，被保持于内周槽(223)的销(23)因来自齿轮主体(22)的弹性变形部(24)的弹性力而被靠压于外齿(31)。因此，由多个销(23)构成的内齿(21)与外齿(31)之间的间隙(游隙)被填埋，从而齿隙减少。由此，在内啮合行星齿轮装置(1、1A、1B)中，具有以下优点：在内齿(21)与外齿(31)的啮合部位处内齿(21)与外齿(31)之间的间隙扩展，也容易抑制齿隙的增大。According to this embodiment, at least at the meshing portion of the inner teeth (21) and the outer teeth (31), the pins (23) held in the inner peripheral grooves (223) are pressed against the outer teeth (31) by the elastic force of the elastic deformation portion (24) of the gear body (22). Therefore, the gap (play) between the inner teeth (21) and the outer teeth (31) formed by the plurality of pins (23) is filled, thereby reducing the backlash. As a result, in the internal meshing planetary gear device (1, 1A, 1B), there is an advantage that the gap between the inner teeth (21) and the outer teeth (31) at the meshing portion of the inner teeth (21) and the outer teeth (31) is expanded, and the increase of the backlash is also easily suppressed.
在第二形态的内啮合行星齿轮装置(1、1A、1B)中，在第一形态的基础上，弹性变形部(24)包含在齿轮主体(22)的外周面遍及周向地形成外周槽(25)而被薄壁化了的部位。In a second form of an internally meshing planetary gear device (1, 1A, 1B), based on the first form, an elastic deformation portion (24) includes a portion where an outer peripheral groove (25) is formed in the circumferential direction on the outer peripheral surface of a gear body (22) and the wall is thinned.
根据该形态，在齿轮主体(22)中的内齿(21)的齿向方向的中央部分形成有弹性变形部(24)，弹性变形部(24)至少与齿轮主体22中的内齿21的齿向方向的两侧部分相比薄壁化、也就是厚度设定得小。 According to this form, an elastic deformation portion (24) is formed in the central portion of the tooth direction of the internal teeth (21) in the gear body (22), and the elastic deformation portion (24) is thinner than at least the two side portions of the tooth direction of the internal teeth 21 in the gear body 22, that is, the thickness is set to be smaller.
在第三形态的内啮合行星齿轮装置(1、1A、1B)中，在第一或第二的基础上，多个内周槽(223)各自的内径(r2)比多个销(23)各自的外径(r1)大。In the third embodiment of the internally meshing planetary gear device (1, 1A, 1B), in addition to the first or second embodiment, the inner diameter (r2) of each of the plurality of inner circumferential grooves (223) is larger than the outer diameter (r1) of each of the plurality of pins (23).
根据该形态，例如，即使弹性变形部(24)变形而内周槽223的内径稍稍变动，内周槽(223)的内径也难以低于销(23)的外径，能够抑制内周槽(223)的开口周缘咬入销(23)的外周面。According to this form, for example, even if the elastic deformation portion (24) is deformed and the inner diameter of the inner circumferential groove 223 changes slightly, the inner diameter of the inner circumferential groove (223) is unlikely to be lower than the outer diameter of the pin (23), and the opening edge of the inner circumferential groove (223) can be prevented from biting into the outer surface of the pin (23).
第四形态的内啮合行星齿轮装置(1、1A、1B)，在第一～三中任一形态的基础上，还包括检测弹性变形部(24)的变形量的检测部(91)。A fourth aspect of the internally meshing planetary gear device (1, 1A, 1B) is based on any one of the first to third aspects and further includes a detection unit (91) for detecting the amount of deformation of the elastic deformation unit (24).
根据该形态，能够根据检测部(91)的变形量求出弹性变形部(24)的变形量，并能够将该变形量反映到例如驱动源(101)的控制等。According to this aspect, the deformation amount of the elastic deformation portion (24) can be obtained from the deformation amount of the detection portion (91), and the deformation amount can be reflected in, for example, the control of the driving source (101).
第五形态的内啮合行星齿轮装置(1、1A、1B)，在第一～四中任意形态的基础上，还包括环状的支承框(9)。齿轮主体(22)在支承框(9)的内侧处固定于支承框(9)。在弹性变形部(24)与支承框(9)之间设置有间隙。The fifth form of the internally meshing planetary gear device (1, 1A, 1B) is based on any of the first to fourth forms and further includes an annular support frame (9). The gear body (22) is fixed to the support frame (9) at the inner side of the support frame (9). A gap is provided between the elastic deformation portion (24) and the support frame (9).
根据该形态，通过设置弹性变形部(24)而下降的齿轮主体(22)的刚性能够由支承框(9)确保。According to this aspect, the rigidity of the gear body (22) which is lowered by providing the elastic deformation portion (24) can be ensured by the support frame (9).
在第六形态的内啮合行星齿轮装置(1、1A、1B)中，在第一～五中任意形态的基础上，齿轮主体(22)在内齿(21)的齿向方向上的从弹性变形部(24)观察至少一侧具有刚性比弹性变形部(24)高的加强部(26)。In a sixth form of an internally meshing planetary gear device (1, 1A, 1B), based on any of the first to fifth forms, the gear body (22) has a reinforcement portion (26) having a higher rigidity than the elastic deformation portion (24) on at least one side in the tooth direction of the internal teeth (21) when viewed from the elastic deformation portion (24).
根据该形态，尽管能够使弹性变形部(24)弹性变形，却也容易对齿轮主体(22)确保所期望的刚性。According to this aspect, although the elastic deformation portion (24) can be elastically deformed, it is also easy to ensure the desired rigidity of the gear body (22).
第七形态的机器人用关节装置(200)包括：第一～六中任一形态的内啮合行星齿轮装置(1、1A、1B)；第一构件(201)，固定于齿轮主体(22)；和第二构件(202)，伴随着行星齿轮(3)相对于内齿齿轮(2)的相对旋转而相对于第一构件(201)相对旋转。The seventh form of the robot joint device (200) includes: an internal meshing planetary gear device (1, 1A, 1B) of any one of the first to sixth forms; a first component (201) fixed to the gear body (22); and a second component (202) that rotates relative to the first component (201) as the planetary gear (3) rotates relative to the internal gear (2).
根据该形态，由多个销(23)构成的内齿(21)与外齿(31)之间的间隙(游隙)被填埋，从而齿隙减少。由此，在内啮合行星齿轮装置(1、1A、1B)中，具有以下优点：在内齿(21)与外齿(31)的啮合部位处内齿(21)与外 齿(31)之间的间隙扩展，也容易抑制齿隙的增大。According to this embodiment, the gap (play) between the internal teeth (21) and the external teeth (31) formed by the plurality of pins (23) is filled, thereby reducing the backlash. As a result, in the internal meshing planetary gear device (1, 1A, 1B), there is an advantage that the internal teeth (21) and the external teeth (31) are meshed at the meshing position. The gap between the teeth (31) is expanded, and the increase of the tooth gap is also easily suppressed.
根据该形态，至少内齿(21)中的与外齿(31)的啮合部位处，被保持于内周槽(223)的销(23)因来自齿轮主体(22)的弹性变形部(24)的弹性力而被靠压于外齿(31)。因此，由多个销(23)构成的内齿(21)与外齿(31)之间的间隙(游隙)被填埋，从而齿隙减少。由此，在内啮合行星齿轮装置(1、1A、1B)中，具有以下优点：在内齿(21)与外齿(31)的啮合部位处内齿(21)与外齿(31)之间的间隙扩展，也容易抑制齿隙的增大。According to this embodiment, at least at the meshing portion of the inner teeth (21) and the outer teeth (31), the pins (23) held in the inner peripheral grooves (223) are pressed against the outer teeth (31) by the elastic force of the elastic deformation portion (24) of the gear body (22). Therefore, the gap (play) between the inner teeth (21) and the outer teeth (31) formed by the plurality of pins (23) is filled, thereby reducing the backlash. As a result, in the internal meshing planetary gear device (1, 1A, 1B), there is an advantage that the gap between the inner teeth (21) and the outer teeth (31) at the meshing portion of the inner teeth (21) and the outer teeth (31) is expanded, and the increase of the backlash is also easily suppressed.
关于第二～六形态的结构，对于内啮合行星齿轮装置(1、1A、1B)而言不是必需设置的结构，可以适当省略。The structures of the second to sixth forms are not essential structures for the internally meshing planetary gear device (1, 1A, 1B) and can be omitted as appropriate.
附图标记说明
1、1A、1B内啮合行星齿轮装置
2内齿齿轮
3行星齿轮
9支承框
21内齿
22齿轮主体
23销
24弹性变形部
25外周槽
26加强部
31外齿
91检测部
200机器人用关节装置
201第一构件
202第二构件
221内周面
223内周槽
r1外径
r2内径Description of Reference Numerals
1, 1A, 1B internal meshing planetary gear device
2 Internal gears
3Planetary gears
9 Support frame
21 internal teeth
22 Gear body
23 pins
24 Elastic deformation part
25 peripheral groove
26 Strengthening Department
31 external teeth
91 Detection Department
200 Robot joint device
201 First Component
202 Second Component
221 inner surface
223 inner groove
r1 outer diameter
r2 inner diameter
工业实用性Industrial Applicability
根据本公开实施例，能够提供容易抑制齿隙的增大的内接合行星齿轮装置和机器人用关节装置。 According to the embodiments of the present disclosure, it is possible to provide an internally meshing planetary gear device and a robot joint device that can easily suppress an increase in backlash.

Claims (7)

  1. 一种内啮合行星齿轮装置，其中，包括：An internally meshing planetary gear device, comprising:
    内齿齿轮，具有：环状的齿轮主体；和多个销，以能够自转的状态保持于在所述齿轮主体的内周面形成的多个内周槽，并构成内齿；和An internal gear having: an annular gear body; and a plurality of pins rotatably held in a plurality of inner peripheral grooves formed on an inner peripheral surface of the gear body to form internal teeth; and
    行星齿轮，具有与所述内齿局部性啮合的外齿，a planetary gear having external teeth partially meshing with the internal teeth,
    通过使所述行星齿轮摆动，由此使所述行星齿轮相对于所述内齿齿轮相对旋转，By swinging the planetary gear, the planetary gear is rotated relative to the internal gear.
    所述齿轮主体在至少形成有所述多个内周槽的部位具有能够弹性变形的弹性变形部。The gear body has an elastically deformable portion that is elastically deformable at least at a location where the plurality of inner peripheral grooves are formed.
  2. 根据权利要求1所述的内啮合行星齿轮装置，其中，The internally meshing planetary gear device according to claim 1, wherein:
    所述弹性变形部包含通过在所述齿轮主体的外周面遍及周向地形成有外周槽而薄壁化了的部位。The elastic deformation portion includes a portion thinned by forming an outer peripheral groove in the circumferential direction on the outer peripheral surface of the gear body.
  3. 根据权利要求1或2所述的内啮合行星齿轮装置，其中，The internally meshing planetary gear device according to claim 1 or 2, wherein:
    所述多个内周槽各自的内径比所述多个销各自的外径大。The inner diameter of each of the plurality of inner circumferential grooves is larger than the outer diameter of each of the plurality of pins.
  4. 根据权利要求1或2所述的内啮合行星齿轮装置，其中，The internally meshing planetary gear device according to claim 1 or 2, wherein:
    所述内啮合行星齿轮装置还包括检测部，该检测部检测所述弹性变形部的变形量。The internally meshing planetary gear device further includes a detection portion that detects an amount of deformation of the elastic deformation portion.
  5. 根据权利要求1或2所述的内啮合行星齿轮装置，其中，The internally meshing planetary gear device according to claim 1 or 2, wherein:
    所述内啮合行星齿轮装置还包括环状的支承框，The internal meshing planetary gear device also includes an annular support frame,
    所述齿轮主体在所述支承框的内侧处固定于所述支承框，The gear body is fixed to the support frame at the inner side of the support frame,
    在所述弹性变形部与所述支承框之间设置有间隙。A gap is provided between the elastic deformation portion and the support frame.
  6. 根据权利要求1或2所述的内啮合行星齿轮装置，其中，The internally meshing planetary gear device according to claim 1 or 2, wherein:
    所述齿轮主体在所述内齿的齿向方向上的从所述弹性变形部观察的至少一侧具有刚性比所述弹性变形部高的加强部。The gear body includes a reinforcement portion having higher rigidity than the elastic deformation portion on at least one side of the internal teeth in the tooth direction as viewed from the elastic deformation portion.
  7. 一种机器人用关节装置，其中，包括：A joint device for a robot, comprising:
    权利要求1或2所述的内啮合行星齿轮装置； The internal meshing planetary gear device according to claim 1 or 2;
    第一构件，固定于所述齿轮主体；和A first member fixed to the gear body; and
    第二构件，伴随着所述行星齿轮相对于所述内齿齿轮的相对旋转，而相对于所述第一构件相对旋转。 The second member rotates relative to the first member in accordance with the relative rotation of the planetary gear with respect to the internal gear.
PCT/CN2023/118372 2022-12-26 2023-09-12 Internal meshing planetary gear device and joint device for robot WO2024139408A1 (en)

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN203548719U (en) * 2013-10-28 2014-04-16 北京配天大富精密机械有限公司 Cycloidal pin wheel speed reducer and robot
CN204647165U (en) * 2015-05-07 2015-09-16 昆山光腾智能机械有限公司 Pin tooth cycloidal reducer
JP2018044592A (en) * 2016-09-13 2018-03-22 Ｓｋｇ株式会社 Robot deceleration transmission device
CN114278707A (en) * 2022-01-30 2022-04-05 陕西长空齿轮有限责任公司 3K-II type planetary reducer
CN114857216A (en) * 2021-02-05 2022-08-05 盟英科技股份有限公司 Speed reducer

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN203548719U (en) * 2013-10-28 2014-04-16 北京配天大富精密机械有限公司 Cycloidal pin wheel speed reducer and robot
CN204647165U (en) * 2015-05-07 2015-09-16 昆山光腾智能机械有限公司 Pin tooth cycloidal reducer
JP2018044592A (en) * 2016-09-13 2018-03-22 Ｓｋｇ株式会社 Robot deceleration transmission device
CN114857216A (en) * 2021-02-05 2022-08-05 盟英科技股份有限公司 Speed reducer
CN114278707A (en) * 2022-01-30 2022-04-05 陕西长空齿轮有限责任公司 3K-II type planetary reducer

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