JP2014185744A - Gear device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gear device which is configured so that an external tooth supporting mechanism can further smoothly support an external gear.SOLUTION: A gear device 1 includes an internal gear 70 having a plurality of internal teeth 73, a rotating shaft 20 having an eccentric cam 22, and an external gear 30 on and in the outer periphery side of which a plurality of external teeth 32 are formed to engage with the internal teeth 73 and a plurality of through-holes 33 are formed to isolate each other in a peripheral direction ZC, respectively, and which is rockingly rotated around a center axis J1 of the rotating shaft 20 with the rotation of the rotating shaft 20 by the eccentric cam 22. The gear device 1 further includes first needle bearings 41, second needle bearings 42 and eccentric bushes 44 as external tooth supporting mechanisms inserted into the through-holes 33 for supporting the external gear 30 during the rocking rotation of the external gear 30. Between the adjacent through-holes 33 in the peripheral direction ZC, the external gear 30 has first lubricating oil reservoir parts 36 and second lubricating oil reservoir parts 37 which are connected to the through-holes 33 and in which lubricating oil LB is filled.

Description

  The present invention relates to a gear device having an external gear and an internal gear.

  2. Description of the Related Art As a conventional gear device, a reduction gear having two external gears attached to an eccentric cam of a rotating shaft via a rolling bearing, and one internal gear meshed with each external gear via an engagement pin It has been known. This speed reduction device converts the rotation of the external gear into a swinging rotation via an eccentric cam of the rotating shaft as the rotating shaft rotates. The reduction gear rotates in a state where the external gear is decelerated with respect to the rotation speed of the rotary shaft based on the difference in the number of teeth between the external gear and the internal gear.

  Further, the conventional speed reducer has a roller as an external gear support mechanism that supports the external gear with respect to the oscillating rotation of the external gear. The rollers are arranged in through holes formed in the external gear so as to be spaced apart from each other in the circumferential direction. The roller supports the external gear by rotating along the inner periphery of the through hole when the external gear rotates and rotates. Note that Patent Document 1 shows an example of a conventional speed reducer.

JP 59-106744 A

  In the conventional gear device (reduction gear), since the roller receives a load due to the swinging rotation of the external gear, it is preferable that the roller rotate smoothly with respect to the inner periphery of the through hole. However, a configuration in which the roller rotates more smoothly with respect to the inner peripheral surface of the through hole has not been proposed in the conventional reduction gear. For this reason, there is room for improvement in this respect.

  In order to solve the above problems, an object of the present invention is to provide a gear device having a configuration in which an external gear support mechanism can support an external gear more smoothly.

  This means includes: “an internal gear having a plurality of internal teeth formed on the inner peripheral side, a rotary shaft disposed on the inner peripheral side of the internal gear via a gap and having an eccentric cam, and the internal gear. A plurality of external teeth that are arranged on the inner peripheral side and mesh with the inner teeth on the outer peripheral side, and a plurality of through holes that are spaced apart from each other in the circumferential direction of the rotating shaft and penetrate in the axial direction of the rotating shaft, An external gear that swings and rotates about the rotation center axis of the rotary shaft by the eccentric cam according to the rotation of the rotary shaft, and the external gear that is inserted into the through-hole and that rotates with respect to the rotary rotation of the external gear. An external gear support mechanism for supporting a gear, and the external gear is connected to the through hole between the through holes adjacent in the circumferential direction and has a lubricating oil reservoir filled with lubricating oil. It has a gear device.

  In the external gear support mechanism, it is preferable that lubricating oil is interposed between the external gear support mechanism and the external gear in order to smoothly support the external gear against the swinging rotation of the external gear. When the lubricating oil is insufficient, the external gear support mechanism and the external gear are in direct contact with each other, and it may be difficult for the external gear support mechanism to smoothly support the external gear.

  Therefore, in the gear device of the present invention, the lubricating oil reservoir is connected to the through hole of the external gear. Thereby, the gear device can supply the lubricating oil in the lubricating oil reservoir to the external gear support mechanism. For this reason, it is suppressed that the lubricating oil between an external gear support mechanism and an external gear is insufficient. Therefore, the external gear support mechanism can support the external gear more smoothly.

One mode of the above means includes a “gear device that connects the through-holes adjacent to each other in the circumferential direction in the lubricating oil reservoir”.
One form of the above-mentioned means is as follows: "The lubricating oil reservoir is a groove-shaped first lubricating oil reservoir recessed from one end face of the external gear in the axial direction; and the other of the external gear in the axial direction. A groove-shaped second lubricating oil reservoir that is recessed from the end surface of the first lubricating oil reservoir, and the first lubricating oil reservoir and the second lubricating oil reservoir are alternately arranged in the circumferential direction. .

  In this gear device, in comparison with the external gear that is assumed that only one of the first lubricating oil reservoir and the second lubricating oil reservoir is formed between the through holes adjacent in the circumferential direction of the rotating shaft, A decrease in strength of the external gear can be suppressed.

  One form of the above-mentioned means is as follows: “The gear device has one external gear, and the lubricating oil reservoir is formed as a groove shape recessed from an end surface of the external gear in the axial direction, The groove depth of the lubricating oil reservoir has a gear device that is at least half the axial dimension of the external gear and smaller than the axial dimension of the external gear.

  In this gear device, the lubricating oil reservoir portion communicates with the central portion in the axial direction of the external tooth support mechanism. Therefore, the gear device can supply the lubricating oil in the lubricating oil reservoir to the axial central portion of the external gear support mechanism.

  One form of the above means is “having a bearing that supports the eccentric cam in a state in which the eccentric cam can rotate with respect to the external gear between the eccentric cam and the external gear, And at least one of an outer circumferential lubricating oil reservoir that communicates the through hole in the radial direction of the rotating shaft, an inner circumferential surface of the external gear, and an inner circumferential lubricating oil reservoir that communicates the through hole in the radial direction. It has a gear device having.

  When the gear device has the outer peripheral side lubricating oil, the outer peripheral side lubricating oil reservoir is connected to the through-hole, so the gear device can supply the lubricating oil in the outer peripheral lubricating oil reservoir to the external tooth support mechanism. It becomes possible. For this reason, it is suppressed that the lubricating oil between an external gear support mechanism and an external gear is insufficient. Therefore, the external gear support mechanism can support the external gear more smoothly.

  Further, when the gear device has the inner peripheral side lubricating oil, the inner peripheral side lubricating oil reservoir is open to the inner peripheral surface of the external gear, and therefore the gear device has a bearing on the inner peripheral lubricating oil reservoir. Lubricating oil can be supplied. For this reason, it is suppressed that the lubricating oil between a bearing and an external gear is insufficient. Therefore, the bearing can support the external gear more smoothly.

  One form of the above-mentioned means is as follows: “The gear device has the outer peripheral lubricating oil reservoir, and the outer peripheral lubricating oil reservoir is formed on a surface different from the meshing surface of the outer teeth with the inner teeth. A gear device.

In the configuration where it is assumed that the outer peripheral lubricating oil reservoir is open on the meshing surface of the outer teeth, the inner teeth may be damaged when the inner teeth contact the opening of the outer peripheral lubricating oil reservoir.
On the other hand, in the gear device according to the present invention, the outer peripheral side lubricating oil reservoir is formed on a surface different from the meshing surface of the external teeth. For this reason, it is suppressed that an internal tooth contacts the opening part of an outer peripheral side lubricating oil reservoir part.

  One form of the above means is that “the external tooth support mechanism has an eccentric bush in which a through hole having a center different from the center of the through hole is formed, and between the external tooth and the internal tooth, The eccentric bushing is filled with lubricating oil, and the eccentric bushing has a portion opposite to the center of the eccentric bushing with respect to the center of the through hole in the eccentric direction connecting the center of the through hole and the center of the eccentric bushing. And a gear device in which a lubricating oil reservoir portion filled with lubricating oil is formed.

  In this gear device, when the outer tooth portion where the outer peripheral side lubricating oil reservoir portion is formed and the inner teeth mesh with each other, the lubricating oil reservoir portion of the eccentric bush overlaps the outer peripheral side lubricating oil reservoir portion in the radial direction. For this reason, the lubricating oil in the outer peripheral side lubricating oil reservoir is pushed into the through hole of the external gear by the lubricating oil filled between the external teeth and the internal teeth. In addition, the lubricating oil in the through hole is pushed into the bearing by the lubricating oil in the outer peripheral lubricating oil reservoir. For this reason, lubricating oil can be supplied to an external-tooth support mechanism and a bearing. Therefore, a shortage of lubricating oil for the external tooth support mechanism and the bearing is suppressed.

  In this gear device, the external gear support mechanism can more smoothly support the external gear.

The top view of the gear apparatus of 1st Embodiment. Sectional drawing of the Z1-Z1 plane of FIG. Sectional drawing of the Z2-Z2 plane of FIG. It is sectional drawing of the external gear of the gear apparatus of 1st Embodiment, (a) is sectional drawing of Z3-Z3 plane of FIG. 3, (b) is an enlarged view of the 2nd lubricating oil reservoir part of (a), (C) is an enlarged view of the first lubricating oil reservoir of (a). It is sectional drawing of the gear apparatus of 2nd Embodiment, and sectional drawing of the plane equivalent to the Z1-Z1 plane of FIG. It is sectional drawing of the gear apparatus of 2nd Embodiment, (a) is sectional drawing of Z5-Z5 plane of FIG. 5, (b) is an enlarged view of the external tooth of (a) and its periphery. Sectional drawing of the 1st lubricating oil reservoir part of the external gear of other embodiment. Sectional drawing of the 1st lubricating oil reservoir part of the external gear of other embodiment. It is sectional drawing of the gear apparatus of other embodiment, and sectional drawing of the plane equivalent to the Z2-Z2 plane of FIG. It is sectional drawing of the gear apparatus of other embodiment, and sectional drawing of the plane equivalent to the Z2-Z2 plane of FIG. It is sectional drawing of the gear apparatus of other embodiment, and sectional drawing of the plane equivalent to the Z2-Z2 plane of FIG. Sectional drawing of the external tooth of other embodiment and its periphery. Sectional drawing of the external tooth of other embodiment and its periphery. It is sectional drawing of the gear apparatus of other embodiment, (a) is sectional drawing of the plane corresponded to Z5-Z5 plane of FIG. 5, (b) is an enlarged view of the external tooth of (a) and its periphery.

(First embodiment)
With reference to FIGS. 1-3, the whole structure of the gear apparatus 1 is demonstrated.
The gear device 1 is applied as a reduction device for a driving portion of a finger joint of a robot hand (not shown). The robot hand includes an input element 2 as a first joint part, an output element 3 as a second joint part (both refer to FIG. 2), and a gear device 1 as a speed reducer. The input element 2 and the output element 3 are coupled so as to be able to rotate relatively. The input element 2 has a motor 2 </ b> A connected to the gear device 1. The gear device 1 rotates the output element 3 relative to the input element 2 in a state where the rotation of the motor 2A is decelerated.

“Axial direction ZA”, “Input direction ZA1”, “Output direction ZA2” (both refer to FIG. 2), “Diameter direction ZB”, “Inward direction ZB1”, “Outward direction ZB2”, And “circumferential direction ZC” are defined as follows. The axial direction ZA corresponds to “the axial direction of the rotating shaft”. The radial direction ZB corresponds to the “radial direction of the rotating shaft”. The circumferential direction ZC corresponds to the “circumferential direction of the rotating shaft”.
(A) The axial direction ZA indicates a direction along the central axis J1 of the gear device 1.
(B) The input direction ZA1 indicates a direction from the output element 3 toward the input element 2 in the axial direction ZA.
(C) The output direction ZA2 indicates a direction from the input element 2 toward the output element 3 in the axial direction ZA.
(D) The radial direction ZB indicates a direction orthogonal to the central axis J1 of the gear device 1.
(E) The inward direction ZB1 indicates a direction approaching the central axis J1 in the radial direction ZB.
(F) The outward direction ZB2 indicates a direction away from the central axis J1 in the radial direction ZB.
(G) The circumferential direction ZC indicates the direction around the central axis J1 of the gear device 1.

  As shown in FIG. 2, the gear device 1 includes an assembly in which a first rotating unit 10, a second rotating unit 40, a stationary unit 60, two inner bearings 90, and two outer bearings 100 are coupled to each other. It has the composition as. The gear device 1 has a configuration in which the rotary units 10 and 40 and the bearings 90 and 100 are accommodated in the stationary unit 60 in the radial direction ZB. The gear device 1 is connected to the input element 2 in the first rotation unit 10. The gear device 1 is connected to the output element 3 in the second rotation unit 40.

  The first rotating unit 10 includes a rotating shaft 20, one external gear 30, a needle bearing 11, two spacers 12, and two detent parts 13. The first rotating unit 10 has a configuration in which an external gear 30 is attached to the rotating shaft 20 via a needle bearing 11. The first rotating unit 10 has a configuration in which each spacer 12 is attached to the rotating shaft 20 via each anti-rotation component 13. The needle bearing 11 corresponds to a “bearing”.

  The rotating shaft 20 has a shaft main body 21 and an eccentric cam 22. The rotary shaft 20 has a configuration in which a shaft main body 21 and an eccentric cam 22 are integrally formed of the same metal material. The rotating shaft 20 rotates integrally with the input element 2 (motor 2A).

  The shaft body 21 has a cylindrical shape in which an internal space penetrating in the axial direction ZA is formed. The shaft main body 21 is formed with eight mounting holes 23 at both ends in the axial direction ZA. The central axis of the shaft body 21 is coaxial with the central axis J1. The shaft body 21 is attached with the motor 2 </ b> A in the attachment hole 23. In this state, the central axis of the shaft body 21 is coaxial with the central axis J2 of the motor 2A. The shaft body 21 is in contact with the first inner ring 91 of the inner bearing 90 on the outer peripheral surface 21A at both ends in the axial direction ZA. The shaft body 21 is subjected to a polishing process at a portion of the outer peripheral surface 21 </ b> A that contacts the first inner ring 91. The surface roughness of the portion of the outer peripheral surface 21 </ b> A that contacts the first inner ring 91 in the shaft body 21 is smaller than the surface roughness of other portions of the rotating shaft 20.

  The eccentric cam 22 is located at the central portion of the shaft body 21 in the axial direction ZA. The eccentric cam 22 extends from the outer peripheral surface 21A of the shaft body 21 in the radial direction ZB. The eccentric cam 22 has a shape in which the dimension in the radial direction ZB between the central axis J1 and the outer peripheral surface of the eccentric cam 22 is different in the circumferential direction ZC (see FIG. 3).

  The needle bearing 11 is located between the eccentric cam 22 and the radial direction ZB of the external gear 30. The needle bearing 11 supports the rotating shaft 20 in a state where the rotating shaft 20 can rotate with respect to the external gear 30. The needle bearing 11 is coated with lubricating oil LB. The lubricating oil LB of the needle bearing 11 is interposed between each needle of the needle bearing 11 and the eccentric cam 22 and between the external gear 30 and each needle of the needle bearing 11. The lubricating oil LB for the needle bearing 11 is creamy at normal temperature.

  The spacer 12 is sandwiched between the eccentric cam 22 and the first inner ring 91 of the inner bearing 90 in the axial direction ZA. The spacer 12 determines the position of the inner bearing 90 in the axial direction ZA with respect to the rotating shaft 20. The rotation of the spacer 12 with respect to the rotation shaft 20 is restricted by the rotation preventing part 13.

  The external gear 30 has a configuration in which external teeth 32 are formed on the outer peripheral portion of a disc-shaped gear body 31. The central axis JD of the external gear 30 is at a position different from the central axis J1. The external gear 30 meshes with the internal gear 70 of the stationary unit 60 at a part of the plurality of external teeth 32.

  The gear body 31 has a disk shape. The gear body 31 has six through holes 33 that accommodate a part of the second rotation unit 40. The through holes 33 are positioned at equal intervals in the circumferential direction ZC on a virtual circle centered on the central axis JD (see FIG. 3).

  The second rotating unit 40 includes six first needle bearings 41, six second needle bearings 42, six pins 43, six eccentric bushes 44, six fixing bolts 45, and a pair of side plates. 50. The second rotating unit 40 has a configuration in which the needle bearings 41 and 42, the pin 43, the eccentric bush 44, and the fixing bolt 45 are inserted into the through hole 33 of the external gear 30. The second rotating unit 40 has a configuration in which a pair of side plates 50 are fixed to each other by a fixing bolt 45 in a state where the external gear 30 is sandwiched from the axial direction ZA. The first needle bearing 41, the second needle bearing 42, and the eccentric bush 44 correspond to an “external tooth support mechanism”.

  The pin 43 is made of a metal material. The pin 43 has a cylindrical shape in which a through hole 43A penetrating in the axial direction ZA is formed. The pin 43 is inserted into the fixing bolt 45. The pins 43 are inserted into the pair of side plates 50 at both ends in the axial direction ZA. The central axis of the through-hole 43 </ b> A of the pin 43 is coaxial with the central axis of the fixing bolt 45.

  The eccentric bush 44 is made of a metal material. The eccentric bush 44 has a cylindrical shape in which a through hole 44A penetrating in the axial direction ZA is formed. The dimension of the eccentric bush 44 in the axial direction ZA is the same as the dimension of the external gear 30 in the axial direction ZA. The central axis of the through hole 44 </ b> A of the eccentric bush 44 is coaxial with the central axis of the through hole 43 </ b> A of the pin 43. The dimension in the radial direction ZB between the central axis of the through hole 44A of the eccentric bush 44 and the outer peripheral surface has a different shape in the circumferential direction ZC (see FIG. 3).

  The first needle bearing 41 is located between the pin 43 and the eccentric bush 44 in the radial direction ZB. The first needle bearing 41 supports the eccentric bush 44 in a state where the eccentric bush 44 can rotate with respect to the pin 43. Lubricating oil LB is applied to the first needle bearing 41. The lubricating oil LB for the first needle bearing 41 is the same as the lubricating oil LB for the needle bearing 11. Lubricating oil LB of the first needle bearing 41 is interposed between the needle of the first needle bearing 41 and the pin 43 and between the needle of the first needle bearing 41 and the eccentric bush 44.

  The second needle bearing 42 is located between the eccentric bush 44 and the radial direction ZB of the through hole 33 of the external gear 30. The second needle bearing 42 supports the eccentric bush 44 in a state where the eccentric bush 44 can rotate with respect to the external gear 30. Lubricating oil LB is applied to the second needle bearing 42. The lubricating oil LB for the second needle bearing 42 is the same as the lubricating oil LB for the first needle bearing 41. The lubricating oil LB of the second needle bearing 42 is interposed between the needle of the second needle bearing 42 and the eccentric bush 44 and between the needle of the second needle bearing 42 and the inner peripheral surface of the through hole 33 of the external gear 30. doing.

  The side plate 50 is made of a metal material. The side plate 50 has a cylindrical shape having a central axis that is coaxial with the central axis J1. The side plate 50 has six bolt insertion holes 51 and six screw holes 52 (see FIG. 1). The side plate 50 has a configuration in which two screw holes 52 are closed by a sealing component 53 (see FIG. 1). The side plate 50 supports the inner bearing 90 at the inner peripheral portion. The side plate 50 supports the outer bearing 100 at the outer peripheral portion. In the side plate 50, the output element 3 is connected through four screw holes 52 that are not closed by the sealing component 53. In this state, the central axis J3 of the output element 3 is coaxial with the central axis J1. In a state where the output element 3 is not attached to the side plate 50, all the screw holes 52 are closed by the sealing component 53, thereby maintaining a sealed state in the gear device 1.

  The side plate 50 is polished on the inner peripheral surface 50A and the outer peripheral surface 50B. The surface roughness of the inner peripheral surface 50A of the side plate 50 and the surface roughness of the outer peripheral surface 50B are smaller than the surface roughness of portions other than the inner peripheral surface 50A and the outer peripheral surface 50B of the side plate 50.

  The bolt insertion holes 51 are formed at an equal distribution of 60 degrees on a virtual circle centered on the central axis J1 (see FIG. 1). The bolt insertion hole 51 is formed with an accommodating portion 51 </ b> A that accommodates the screw head of the fixing bolt 45. The two side plates 50 are arranged such that the accommodating portions 51A of the side plate 50 on the input direction ZA1 side and the accommodating portions 51A of the side plate 50 on the output direction ZA2 side are alternate in the circumferential direction ZC (see FIG. 1). ).

  The screw hole 52 (see FIG. 1) is located between the bolt insertion holes 51 adjacent in the circumferential direction ZC. The screw hole 52 penetrates the side plate 50 in the axial direction ZA. The screw holes 52 are formed at an equal distribution of 60 degrees on a virtual circle centered on the central axis J1 (see FIG. 1).

  The stationary unit 60 has a configuration in which an internal gear 70 is sandwiched between the axial directions ZA of the pair of housings 80. The stationary unit 60 has a configuration in which a pair of housings 80 and an internal gear 70 are coupled by twelve fixing bolts 61 and twelve fixing nuts 62.

  The internal gear 70 is made of a metal material. The internal gear 70 has a configuration in which a gear portion 72 and a fixed portion 71 are integrally formed. The internal gear 70 has a configuration in which a fixed portion 71 extends from an annular gear portion 72 toward the outer direction ZB2. The internal gear 70 has internal teeth 73 formed on the inner peripheral side of the gear portion 72. Lubricating oil LB is applied to the inner teeth 73 and the outer teeth 32. As the lubricating oil LB for the inner teeth 73 and the outer teeth 32, the same lubricating oil LB for the second needle bearing 42 is used.

  The housing 80 is made of a metal material. The housing 80 has a bearing holding portion 81 and a fixed portion 82. The housing 80 has a configuration in which the fixed portion 82 extends from the end on the internal gear 70 side in the bearing holding portion 81 toward the outer direction ZB2.

  The bearing holding portion 81 has a cylindrical shape having a central axis that is coaxial with the central axis J1. The bearing holding portion 81 is in contact with the second outer ring 102 of the outer bearing 100 on the inner peripheral surface 81A. The bearing holding portion 81 is polished on the inner peripheral surface 81A. The surface roughness of the inner peripheral surface 81 </ b> A of the bearing holding portion 81 is smaller than the surface roughness of other portions of the housing 80.

  The fixed portion 82 has an annular shape in plan view. The fixed portion 82 is in contact with the end surface in the axial direction ZA of the fixed portion 71 of the internal gear 70. Each fixed portion 82 of the pair of housings 80 sandwiches the fixed portion 71 of the internal gear 70 in the axial direction ZA.

  The inner bearing 90 includes a first inner ring 91, a first outer ring 92, balls as a plurality of rolling elements 93, a retainer 94, grease (not shown), and two first seal parts 95. The inner bearing 90 has a configuration in which an internal space between the first inner ring 91 and the first outer ring 92 (hereinafter referred to as “internal space S1”) is sealed by two first seal components 95. The inner bearing 90 has a configuration in which grease is sealed in the inner space S1. The inner bearing 90 supports the rotating shaft 20 in a state where the rotating shaft 20 can rotate with respect to the side plate 50.

  The outer bearing 100 includes a second inner ring 101, a second outer ring 102, balls as a plurality of rolling elements 103, a cage 104, grease (not shown), and two second seal parts 105. The outer bearing 100 has a configuration in which an internal space between the second inner ring 101 and the second outer ring 102 (hereinafter, “internal space S2”) is sealed by two second seal components 105. The outer bearing 100 has a configuration in which grease is sealed in the inner space S2. The outer bearing 100 supports the side plate 50 in a state where the side plate 50 can rotate with respect to the housing 80.

The detailed configuration of the external gear 30 will be described with reference to FIGS. 3 and 4.
As shown in FIG. 3, the gear body 31 of the external gear 30 includes six inner peripheral through holes 34, six outer peripheral through holes 35, three first lubricating oil reservoirs 36, and 3. The second lubricating oil reservoir 37 is provided.

  The inner circumferential side through hole 34 penetrates the gear body 31 in the axial direction ZA. The inner peripheral side through hole 34 is located in the inner peripheral side portion of the gear body 31. The inner peripheral side through-holes 34 are located at 60 ° equidistant from the central axis JD of the external gear 30. The inner peripheral side through hole 34 is located between the through holes 33 adjacent in the circumferential direction ZC. The inner circumferential side through hole 34 is formed for the purpose of reducing the weight of the external gear 30.

  The outer peripheral side through hole 35 penetrates the gear body 31 in the axial direction ZA. The outer peripheral side through hole 35 is located at the outer peripheral side portion of the gear body 31. The outer circumferential side through-holes 35 are located at 60 ° equidistant from the central axis JD. The outer peripheral side through hole 35 is located between the through holes 33 adjacent to each other in the circumferential direction ZC. The inner diameter of the outer peripheral side through hole 35 is larger than the inner diameter of the inner peripheral side through hole 34. The outer peripheral side through hole 35 is formed for the purpose of reducing the weight of the external gear 30.

  Each of the lubricating oil reservoirs 36 and 37 connects the through holes 33 adjacent to each other in the circumferential direction ZC. Each of the lubricating oil reservoirs 36 and 37 has an arc shape with the central axis JD of the external gear 30 as the center. Each of the lubricating oil reservoirs 36 and 37 is located between the inner circumferential side through hole 34 and the outer circumferential side through hole 35 in the radial direction ZB. The lubricating oil reservoirs 36 and 37 are alternately arranged in the circumferential direction ZC. The lubricating oil reservoirs 36 and 37 are filled with lubricating oil LB to be supplied to the second needle bearing 42. The width dimension HA1 (see FIG. 4C) of the first lubricating oil reservoir 36 and the width dimension HA2 (see FIG. 4B) of the second lubricating oil reservoir 37 are outside the needle of the second needle bearing 42. Each is set below the diameter. Each of the lubricating oil reservoirs 36 and 37 is formed in the gear body 31 at a position overlapping the screw hole 52 (see FIG. 1) of the side plate 50 in the axial direction ZA. The same lubricating oil LB as that of the second needle bearing 42 is used as the lubricating oil LB of the lubricating oil reservoirs 36 and 37.

  As shown in FIG. 4A, the first lubricating oil reservoir 36 has a groove shape that is recessed from the end surface 31A in the input direction ZA1 of the gear body 31 toward the output direction ZA2. As shown in FIG. 4 (c), the bottom surface 36A of the first lubricating oil reservoir 36 is more in the output direction ZA2 than the half position in the axial direction ZA of the gear body 31 indicated by the two-dot chain line in the drawing. Is located. The groove depth HB1 of the first lubricating oil reservoir 36 is the same in the circumferential direction ZC. The end face 31A in the input direction ZA1 of the gear body 31 corresponds to “one end face of the external gear”.

  As shown in FIG. 4A, the second lubricating oil reservoir 37 has a groove shape that is recessed from the end surface 31B in the output direction ZA2 of the gear body 31 toward the input direction ZA1. As shown in FIG. 4B, the bottom surface 37 </ b> A of the second lubricating oil reservoir 37 is positioned in the input direction ZA <b> 1 rather than the half position (two-dot chain line) of the gear body 31 in the axial direction ZA. The groove depth HB2 of the second lubricating oil reservoir 37 is the same in the circumferential direction ZC. The end face 31B of the gear body 31 in the output direction ZA2 corresponds to “the other end face of the external gear”.

The operation of the gear device 1 will be described with reference to FIG.
In the gear device 1, as the motor 2A (see FIG. 2) rotates at the rotation speed N, the rotation shaft 20 rotates at the rotation speed N about the center axis J1. As the rotary shaft 20 rotates, the eccentric cam 22 rotates at the rotational speed N about the central axis J1. At this time, since the external gear 30 is pushed by the eccentric cam 22 as the eccentric cam 22 rotates, the external gear 30 swings and rotates at the rotational speed N around the central axis J1.

  The external gear 30 meshes with the internal gear 70 by the number of teeth Z2 of the internal gear 70 per one oscillating rotation of the external gear 30. At this time, the external gear 30 rotates by the difference between the number of teeth Z1 of the external gear 30 and the number of teeth Z2 of the internal gear 70. That is, the external gear 30 rotates by (Z2-Z1) / Z1 rotation when the external gear 30 rotates by one swing.

  Further, the eccentric bush 44 rotates around the central axis of the fixing bolt 45 as the external gear 30 swings and rotates. For this reason, the swinging rotation of the through hole 33 due to the swinging rotation of the external gear 30 is absorbed by the eccentric bush 44. On the other hand, the rotation of the external gear 30 is transmitted to the pin 43 via the eccentric bush 44. For this reason, the pin 43 revolves around the central axis J1 as the external gear 30 rotates.

  The side plate 50 (see FIG. 2) rotates about the central axis J1 through the fixing bolt 45 as the pin 43 revolves. The output element 3 attached to the side plate 50 rotates around the central axis J1 at a rotational speed of N × (Z2−Z1) / Z1.

With reference to FIG. 2 and FIG. 3, the effect | action of the gear apparatus 1 of this embodiment is demonstrated.
The gear device 1 has a first function and a second function. The first function indicates a function of supplying the lubricating oil LB to the second needle bearing 42. The second function is a function of suppressing the leakage of the lubricating oil LB to the outside of the gear device 1.

The detailed contents of the first function will be described with reference to FIG.
The second needle bearing 42 supports the eccentric bush 44 in a state where the eccentric bush 44 can rotate around the central axis of the fixing bolt 45 with respect to the swinging rotation of the external gear 30. Therefore, the second needle bearing 42 receives a force that the external gear 30 acts on the eccentric bush 44 due to the swinging rotation of the external gear 30. As a result, the second needle bearing 42 rotates and revolves around the center of the through hole 33 while being pressed against the eccentric bush 44 by the external gear 30. For this reason, when it is assumed that the lubricating oil LB of the second needle bearing 42 is insufficient, the needle of the second needle bearing 42 is seized to the external gear 30 and the eccentric bush 44, and the second needle bearing 42 is smooth. There is a risk of not rotating and revolving. Further, the eccentric bush 44 may not rotate smoothly.

  The gear device 1 of the present embodiment has a configuration in which each of the lubricating oil reservoirs 36 and 37 communicates with the through hole 33. Thereby, when the lubricating oil LB of the second needle bearing 42 is reduced, the lubricating oil LB of the lubricating oil reservoirs 36 and 37 is supplied to the second needle bearing 42. For this reason, it is suppressed that the lubricating oil LB of the 2nd needle bearing 42 runs short. Therefore, since the second needle bearing 42 rotates and revolves smoothly, the eccentric bush 44 rotates smoothly via the second needle bearing 42.

  Further, the gear device 1 is configured to have one external gear 30. Therefore, when the gear device 1 and the assumed gear device have the same physique compared to the gear device assumed to have two external gears, the axial direction of the external gear 30 per one piece The dimension of ZA is large. As a result, in the gear device 1, it is difficult for the lubricating oil LB to be supplied to the central portion of the second needle bearing 42 in the axial direction ZA.

  Therefore, in the gear device 1 of the present embodiment, the groove depths HB1, HB2 (see FIG. 4) of the lubricating oil reservoirs 36, 37 are larger than half of the dimension of the external gear 30 in the axial direction ZA, and The external gear 30 is formed to be smaller than the dimension in the axial direction ZA. For this reason, the lubricating oil LB in each of the lubricating oil reservoirs 36 and 37 is likely to be supplied to the central portion of the second needle bearing 42 in the axial direction ZA. In addition, since the lubricating oil reservoirs 36 and 37 are connected to the through holes 33, the lubricating oil LB is supplied over the entire axial direction ZA of the second needle bearing 42.

The detailed contents of the second function will be described with reference to FIG.
In the gear device 1, assuming that the lubricating oil LB of the external teeth 32 and the internal teeth 73 and the lubricating oil LB of the needle bearings 41 and 42 leak from the inside of the gear device 1 to the outside, There is a possibility that the lubricating oil LB is insufficient. For this reason, in the gear apparatus 1, it is preferable that the lubricating oil LB of each needle bearing 41 and 42 does not leak outside from the gear apparatus 1.

  The following first to sixth paths can be considered as paths through which the lubricating oil LB may leak. The first path is formed between the outer peripheral surface 21 </ b> A of the rotating shaft 20 and the first inner ring 91 of the inner bearing 90. The second path is formed between the inner peripheral surface 50 </ b> A of the side plate 50 and the first outer ring 92 of the inner bearing 90. The third path is formed between the outer peripheral surface 50 </ b> B of the side plate 50 and the second inner ring 101 of the outer bearing 100. The fourth path is formed between the inner peripheral surface 81 </ b> A of the housing 80 and the second outer ring 102 of the outer bearing 100. The fifth path is formed between the first inner ring 91 and the first outer ring 92 of the inner bearing 90. The sixth path is formed between the second inner ring 101 and the second outer ring 102 of the outer bearing 100.

  In contrast, the gear device 1 of the present embodiment has the following configuration for each path. That is, in the first path, the first inner ring 91 of the inner bearing 90 is press-fitted into the outer peripheral surface 21 </ b> A of the rotary shaft 20. In the second path, the first outer ring 92 of the inner bearing 90 is press-fitted into the inner peripheral surface 50 </ b> A of the side plate 50. In the third path, the second inner ring 101 of the outer bearing 100 is press-fitted into the outer peripheral surface 50 </ b> B of the side plate 50. In the fourth path, the second outer ring 102 of the outer bearing 100 is press-fitted into the inner peripheral surface 81 </ b> A of the housing 80. In the fifth path, the space between the first inner ring 91 and the first outer ring 92 of the inner bearing 90 is sealed by the first seal component 95. In the sixth path, the space between the second inner ring 101 and the second outer ring 102 of the outer bearing 100 is sealed by the second seal component 105.

  For this reason, in the 1st-4th path | route, formation of the clearance gap for the lubricating oil LB to pass through is suppressed. In the fifth and sixth paths, the seal parts 95 and 105 prevent the lubricating oil LB from passing through the internal spaces S1 and S2 of the bearings 90 and 100. Therefore, leakage of the lubricating oil LB to the outside of the gear device 1 is suppressed.

  Further, as a configuration of a gear device in which the inside of the device is hermetically sealed, the seal components 95 and 105 are omitted from the bearings 90 and 100, and each of the bearings 90 and 100 has a gear device having a seal component such as an oil seal ( Hereinafter, a “virtual gear device”) is considered. The virtual gear device attaches a seal component to the bearings 90 and 100 on the opposite side of the external gear 30 in the axial direction ZA. For this reason, the dimension of the axial direction ZA becomes large in a virtual gear apparatus.

  On the other hand, in the gear device 1 of this embodiment, since the bearings 90 and 100 have the seal parts 95 and 105, it is not necessary to attach a seal part such as an oil seal to the gear apparatus 1 separately from the bearings 90 and 100. . Therefore, the gear device 1 has a smaller dimension in the axial direction ZA than the virtual gear device.

The gear device 1 of the present embodiment has the following effects.
(1) The external gear 30 has a first lubricant reservoir 36 and a second lubricant reservoir 37. According to this configuration, the gear device 1 can supply the lubricating oil LB of the lubricating oil reservoirs 36 and 37 to the second needle bearing 42. For this reason, it is suppressed that the lubricating oil of the 2nd needle bearing 42 runs short. Thus, the eccentric bush 44 rotates more smoothly with respect to the swinging rotation of the external gear 30 via the second needle bearing 42. Therefore, the gear device 1 is configured so that the external gear 30 is smoothed by the second needle bearing 42 and the eccentric bush 44 as compared with a gear device that is assumed to include an external gear in which the lubricating oil reservoirs 36 and 37 are omitted. Can be supported.

  (2) The external gear 30 has a configuration in which the first lubricating oil reservoirs 36 and the second lubricating oil reservoirs 37 are alternately formed in the circumferential direction ZC. According to this configuration, it is assumed that the first lubricant reservoir 36 is formed instead of the second lubricant reservoir 37, and the second lubricant reservoir 37 replaces the first lubricant reservoir 36. Compared to the configuration assumed to be formed, a decrease in strength of the external gear 30 is suppressed.

  (3) The groove depths HB1 and HB2 of the lubricating oil reservoirs 36 and 37 are larger than half of the axial direction ZA of the external gear 30 and smaller than the dimension of the external gear 30 in the axial direction ZA. According to this configuration, the lubricating oil LB in each of the lubricating oil reservoirs 36 and 37 can be supplied to the central portion of the second needle bearing 42 in the axial direction ZA.

  In addition, the gear device 1 is configured to be able to supply the lubricating oil LB of the lubricating oil reservoirs 36 and 37 to the second needle bearings 42, respectively. For this reason, the gear device 1 can supply the lubricating oil LB over the entire axial direction ZA of each second needle bearing 42.

  (4) In the gear device 1, the inner bearing 90 is press-fitted into the rotary shaft 20 and the side plate 50, and the outer bearing 100 is press-fitted into the side plate 50 and the housing 80. In addition, the bearings 90 and 100 have their internal spaces S1 and S2 sealed with seal parts 95 and 105, respectively. According to this configuration, the lubricating oil LB in the gear device 1 can be prevented from leaking outside the gear device 1. Moreover, the dimension of the axial direction ZA of the gear apparatus 1 can be made small compared with a virtual gear apparatus.

  (5) The surface roughness of the outer peripheral surface 21 </ b> A of the rotating shaft 20 is smaller than the surface roughness of other portions of the rotating shaft 20. Further, the surface roughness of the inner peripheral surface 50 </ b> A and the outer peripheral surface 50 </ b> B of the side plate 50 is smaller than the surface roughness of other portions of the side plate 50. The surface roughness of the inner peripheral surface 81 </ b> A of the housing 80 is smaller than the surface roughness of other portions of the housing 80. According to this configuration, formation of a gap between the first to fourth paths can be further suppressed. Therefore, the effect of suppressing the lubricating oil LB in the gear device 1 from leaking outside the gear device 1 is enhanced.

  (6) The side plate 50 has a screw hole 52. Each of the lubricating oil reservoirs 36 and 37 is formed in a portion of the gear body 31 that overlaps the screw hole 52 in the axial direction ZA. According to this configuration, the lubricating oil LB can be injected into the gear device 1 through the screw hole 52. In addition, the lubricant LB can be directly injected into the lubricant reservoirs 36 and 37 via the screw holes 52.

(Second Embodiment)
5 and 6 show the gear device 1 of the second embodiment. The gear device 1 has the following differences as main differences from the gear device 1 of the first embodiment shown in FIGS. 2 and 3. That is, the configurations of the external gear 110 and the eccentric bush 120 are different. Below, the detail of a different point from the gear apparatus 1 of 1st Embodiment is demonstrated, about the structure which is common in 1st Embodiment, the same code | symbol is attached | subjected and the part or all of the description is abbreviate | omitted.

  As shown in FIG. 6, the external gear 110 has a configuration in which a plurality of external teeth 112 are formed on the outer peripheral surface of a disc-shaped gear body 111. The central axis JD2 of the external gear 110 is different from the central axis J1. The external gear 110 meshes with the internal teeth 73 in a part of the plurality of external teeth 112.

  The gear body 111 has a disk shape. The gear body 111 includes six through holes 113, six inner peripheral through holes 114, six outer peripheral through holes 115, six outer peripheral oil reservoirs 116, and six inner peripheral lubrications. An oil reservoir 117 is provided.

  The through hole 113 passes through the gear body 111 in the axial direction ZA. The through hole 113 accommodates a part of the second rotation unit 40. The through holes 113 are located at equal intervals in the circumferential direction ZC on a virtual circle centered on the central axis JD2.

  The inner peripheral side through hole 114 passes through the gear body 111 in the axial direction ZA. The inner peripheral side through hole 114 is located in the inner peripheral side portion of the gear body 111. The inner peripheral side through holes 114 are equally spaced by 60 ° with the central axis JD2 as the center. The inner peripheral side through hole 114 is located between the through holes 113 adjacent in the circumferential direction ZC. The inner peripheral side through hole 114 is formed for the purpose of reducing the weight of the external gear 110.

  The outer peripheral side through hole 115 penetrates the gear body 111 in the axial direction ZA. The outer peripheral side through-hole 115 is located on the outer peripheral side portion of the gear body 111. The outer peripheral side through-holes 115 are located at 60 ° equidistant from the central axis JD2. The outer peripheral side through hole 115 is located between the through holes 113 adjacent to each other in the circumferential direction ZC. The outer peripheral side through hole 115 is formed for the purpose of reducing the weight of the external gear 110.

  The outer peripheral side lubricating oil reservoirs 116 are located at 60 ° equidistant from the central axis JD2. The outer peripheral side lubricating oil reservoir 116 is formed in a portion of the gear body 111 that overlaps the center of the through hole 113 in the radial direction ZB. The outer peripheral side lubricating oil reservoir 116 connects the external teeth 112 and the through holes 113 in the radial direction ZB. As shown in FIG. 6B, the outer peripheral side lubricating oil reservoir 116 opens the tooth tip surface 112 </ b> A of the external tooth 112. The width dimension HC1 of the outer circumferential lubricating oil reservoir 116 is smaller than the outer diameter of the needle of the second needle bearing 42. The outer peripheral side lubricating oil reservoir 116 is formed at the center position of the gear body 111 in the axial direction ZA (see FIG. 5).

  As shown in FIG. 6A, the inner circumferential side lubricating oil reservoirs 117 are located at 60 ° equidistant centering on the central axis JD2. The inner circumferential side lubricating oil reservoir 117 is formed in a portion of the gear body 111 that overlaps with the outer circumferential lubricating oil reservoir 116 in the radial direction ZB. The inner peripheral side lubricating oil reservoir 117 connects the inner peripheral surface 111A of the gear body 111 and the through hole 113 in the radial direction ZB. The width dimension HC2 of the inner circumferential lubricating oil reservoir 117 is smaller than the outer diameter of the needle of the second needle bearing 42. The inner peripheral side lubricating oil reservoir 117 is formed at the center position of the gear body 111 in the axial direction ZA (see FIG. 5).

The eccentric bush 120 has a through hole 121, a first lubricating oil reservoir 122, and a second lubricating oil reservoir 123.
The through hole 121 has a center different from the center of the through hole 113. Hereinafter, a direction connecting the center of the through hole 113 and the center of the through hole 121 is referred to as an “eccentric direction”.

  The first lubricating oil reservoir 122 is formed in the portion of the eccentric bush 120 opposite to the center of the through hole 121 with respect to the center of the through hole 113 in the eccentric direction. That is, the first lubricating oil reservoir 122 is formed in the portion where the thickness in the radial direction of the eccentric bush 120 in FIG. The first lubricating oil reservoir 122 penetrates the eccentric bush 120 in the radial direction of the eccentric bush 120. The first lubricating oil reservoir 122 is filled with lubricating oil LB. The first lubricating oil reservoir 122 connects the space in which the second needle bearing 42 is disposed and the internal space of the through hole 121.

  The second lubricating oil reservoir 123 is formed in the portion of the eccentric bush 120 on the center side of the through hole 121 with respect to the center of the through hole 113 in the eccentric direction. That is, the second lubricating oil reservoir 123 is formed in a portion where the radial thickness of the eccentric bush 120 in FIG. 6A is the smallest. The second lubricating oil reservoir 123 passes through the eccentric bush 120 in the radial direction of the eccentric bush 120. The second lubricating oil reservoir 123 is filled with lubricating oil LB. The second lubricating oil reservoir 123 communicates the space in which the second needle bearing 42 is disposed and the internal space of the through hole 121.

The operation of the gear device 1 of the present embodiment will be described.
In the gear device 1, a portion where the external teeth 112 and the internal teeth 73 of the internal gear 70 mesh with each other is moved in the circumferential direction ZC by the rotation of the external gear 110. When the external teeth 112 and the internal teeth 73 are engaged as shown in FIG. 6, the first lubricating oil of the outer peripheral side lubricating oil reservoir 116 and the eccentric bush 120 adjacent to the meshing portions of the external teeth 112 and the internal teeth 73. The reservoir 122, the second lubricant reservoir 123, and the inner peripheral oil reservoir 117 of the external gear 110 are aligned in the radial direction ZB.

  In this state, the lubricating oil LB in the gear device 1 operates as follows. That is, the lubricating oil LB applied to the outer teeth 112 and the inner teeth 73 is pushed toward the second needle bearing 42 via the outer peripheral lubricating oil reservoir 116 by the engagement of the outer teeth 112 and the inner teeth 73. The lubricating oil LB of the second needle bearing 42 is pushed into the first lubricating oil reservoir 122 of the eccentric bush 120 and the inner circumferential lubricating oil reservoir 117 of the external gear 110. The lubricating oil LB in the first lubricating oil reservoir 122 is pushed into the first needle bearing 41. The lubricating oil LB of the first needle bearing 41 is pushed into the second lubricating oil reservoir 123 of the eccentric bush 120. The lubricating oil LB in the second lubricating oil reservoir 123 is pushed into the inner circumferential lubricating oil reservoir 117. Then, the lubricating oil LB in the inner circumferential lubricating oil reservoir 117 is pushed into the needle bearing 11.

  Thus, since the lubricating oil LB in the gear device 1 operates, the lubricating oil LB is supplied to the second needle bearing 42 and the needle bearing 11. Therefore, a shortage of the lubricating oil LB for the second needle bearing 42 and the needle bearing 11 is suppressed.

The gear device 1 of the present embodiment has the following effects in addition to the effects (4) and (5) of the gear device 1 of the first embodiment.
(7) The external gear 110 has an outer peripheral side lubricating oil reservoir 116 and an inner peripheral lubricating oil reservoir 117. According to this configuration, the gear device 1 can supply the lubricating oil LB of the outer circumferential lubricating oil reservoir 116 to the second needle bearing 42. For this reason, it is suppressed that the lubricating oil LB of the 2nd needle bearing 42 runs short. Therefore, the second needle bearing 42 can support the external gear 110 more smoothly than the gear device that is assumed not to have the outer peripheral side lubricating oil reservoir 116. In addition, the gear device 1 can supply the lubricating oil LB in the inner circumferential lubricating oil reservoir 117 to the needle bearing 11. For this reason, it is suppressed that the lubricating oil LB of the needle bearing 11 is insufficient. Therefore, the needle bearing 11 can support the external gear 110 more smoothly as compared with a gear device that is assumed not to have the inner circumferential lubricating oil reservoir 117.

  (8) In the configuration in which it is assumed that the outer peripheral lubricating oil reservoir portion is opened on the meshing surface of the outer teeth where the inner teeth contact, the inner teeth are brought into contact with the opening of the outer peripheral lubricating oil reservoir portion. It may be damaged.

  On the other hand, in the gear device 1 of the present embodiment, the outer peripheral side lubricating oil reservoir 116 is formed on the tooth tip surface 112A different from the meshing surface of the external teeth 112. For this reason, it is suppressed that the internal tooth 73 contacts the opening part of the outer peripheral side lubricating oil reservoir part 116. FIG. Therefore, the internal teeth 73 are prevented from being damaged due to the outer peripheral lubricating oil reservoir 116.

  (9) In the gear device 1, when the outer teeth 112 where the outer peripheral side lubricating oil reservoir 116 is formed and the inner teeth 73 mesh with each other, the first lubricating oil reservoir 122 of the eccentric bush 120 is used as the outer peripheral lubricating oil. It overlaps with the reservoir 116 in the radial direction ZB. For this reason, the lubricating oil LB in the outer peripheral side lubricating oil reservoir 116 is pushed into the through hole 113 of the external gear 110 by the lubricating oil LB filled between the external teeth 112 and the internal teeth 73. In addition, the lubricating oil in the through hole 113 is pushed into the needle bearing 11 by the lubricating oil LB in the outer peripheral lubricating oil reservoir 116. For this reason, the lubricating oil LB can be supplied to the second needle bearing 42 and the needle bearing 11. Therefore, a shortage of the lubricating oil LB for the second needle bearing 42 and the needle bearing 11 is suppressed.

(Other embodiments)
The gear device includes an embodiment different from the above embodiments. Hereinafter, the modification of each said embodiment as other embodiment of this gear apparatus is shown. The following modifications can be combined with each other.

The first lubricating oil reservoir 36 of the external gear 30 of the first embodiment has the same width dimension HA1 over the entire axial direction ZA. However, the shape of the first lubricating oil reservoir is not limited to the content exemplified in the first embodiment. For example, the first lubricating oil reservoir of the modified example has the following structure. The second lubricating oil reservoir 37 can be similarly changed.
(A) As shown in FIG. 7, the first lubricating oil reservoir 38 is formed in a tapered shape in which the width dimension HA <b> 1 becomes smaller toward the output direction ZA <b> 2. According to this structure, compared with the external gear 30 having the first lubricating oil reservoir 36, a decrease in strength of the external gear 30 due to the first lubricating oil reservoir is suppressed.
(B) As shown in FIG. 8, the first lubricating oil reservoir 39 is formed in a shape in which the width dimension HA11 on the input direction ZA1 side is larger than the width dimension HA12 on the output direction ZA2 side.

  -Each lubricating oil pool part 36, 37 of 1st Embodiment is formed between the through-holes 33 adjacent to the circumferential direction ZC. However, the number of the lubricating oil reservoirs 36 and 37 is not limited to the content exemplified in the first embodiment. For example, as shown in FIG. 9, two lubricating oil reservoirs 36 and 37 of the modified example are formed between the through holes 33 adjacent to each other in the circumferential direction ZC while being separated from each other in the radial direction ZB. .

  The lubricating oil reservoirs 36 and 37 of the above modification of FIG. 9 are alternately arranged in the circumferential direction ZC. However, the configuration of each lubricating oil reservoir 36, 37 is not limited to the content of the above modification. For example, as shown in FIG. 10, each of the lubricating oil reservoirs 36 and 37 of another modified example has the lubricating oil reservoirs 36 and 37 in the radial direction ZB between the through holes 33 adjacent to each other in the circumferential direction ZC. It is formed alternately.

  -Each lubricating oil reservoir part 36 and 37 of 1st Embodiment is formed as circular arc shape centering on the central axis JD of the external gear 30. FIG. However, the shape of each lubricating oil pool part 36 and 37 is not restricted to the content illustrated by 1st Embodiment. For example, each of the lubricating oil reservoirs 36 and 37 of the modified example is formed in a shape that linearly connects the through holes 33 adjacent in the circumferential direction ZC. According to this configuration, when each of the lubricating oil reservoirs 36 and 37 is formed by cutting, each of the lubricating oil reservoirs 36 and 37 of the modified example is the arc-shaped lubricating oil reservoir 36 of the first embodiment. , 37 is easier to process.

  The groove depths HB1, HB2 of the lubricating oil reservoirs 36, 37 of the first embodiment are equal over the circumferential direction ZC. However, the groove depths HB1 and HB2 of the lubricating oil reservoirs 36 and 37 are not limited to the contents exemplified in the first embodiment. For example, the groove depths HB1 and HB2 of the lubricating oil reservoirs 36 and 37 of the modification are increased toward the through hole 33 in the circumferential direction ZC. Further, the groove depths HB1, HB2 of the lubricating oil reservoirs 36, 37 of another modified example become smaller toward the through hole 33 in the circumferential direction ZC.

  The bottom surface 36A of the first lubricating oil reservoir 36 of the first embodiment is located in the output direction ZA2 rather than the half position (the two-dot chain line in FIG. 4) of the external gear 30 in the axial direction ZA. However, the configuration of the first lubricating oil reservoir 36 is not limited to the content exemplified in the first embodiment. For example, the bottom surface 36 </ b> A of the first lubricating oil reservoir 36 of the modified example is formed at the same position as the half position of the external gear 30 in the axial direction ZA. Further, the bottom surface 36 </ b> A of the first lubricating oil reservoir 36 of another modified example is located in the input direction ZA <b> 1 rather than a half position in the axial direction ZA of the external gear 30.

  The bottom surface 37 </ b> A of the second lubricating oil reservoir portion 37 of the first embodiment is located in the input direction ZA <b> 1 rather than the half position of the external gear 30 in the axial direction ZA. However, the configuration of the second lubricating oil reservoir 37 is not limited to the content exemplified in the first embodiment. For example, the bottom surface 37 </ b> A of the second lubricating oil reservoir 37 of the modified example is formed at the same position as the half position of the external gear 30 in the axial direction ZA. Further, the bottom surface 37 </ b> A of the second lubricating oil reservoir 37 of another modified example is located in the output direction ZA <b> 2 rather than the half position of the external gear 30 in the axial direction ZA.

  In the lubricating oil reservoirs 36 and 37 of the first embodiment, the width dimensions HA1 and HA2 of the lubricating oil reservoirs 36 and 37 can be made larger than the outer diameter of the needle of the second needle bearing 42.

  -Each lubricating oil sump part 36 and 37 of 1st Embodiment is formed as a groove | channel shape dented from the end surface of the axial direction ZA of the external gear 30. FIG. However, the shape of each lubricating oil pool part 36 and 37 is not restricted to the content illustrated by 1st Embodiment. For example, each of the lubricating oil reservoirs 36 and 37 of the modified example is formed as a through hole connecting the through holes 33 adjacent to each other in the circumferential direction ZC at the central portion in the axial direction ZA of the external gear 30.

  The respective lubricant reservoirs 36 and 37 of the first embodiment connect the through holes 33 adjacent to each other in the circumferential direction ZC. However, the configuration of each of the lubricating oil reservoirs 36 and 37 is not limited to the content exemplified in the first embodiment. For example, as shown in FIG. 11, each of the lubricating oil reservoirs 36 and 37 of the modification is divided at the central portion in the circumferential direction ZC. In short, each of the lubricating oil reservoirs 36 and 37 has a through hole 33 adjacent to the circumferential direction ZC as long as the lubricating oil LB can be supplied to the second needle bearing 42 disposed in the through hole 33. The structure which is not mutually connected may be sufficient.

-In the external gear 30 of 1st Embodiment, either the 1st lubricating oil pool part 36 and the 2nd lubricating oil pool part 37 can also be abbreviate | omitted.
-In the external gear 30 of 1st Embodiment, at least one of the outer peripheral side lubricating oil reservoir part 116 and the inner peripheral side lubricating oil reservoir part 117 of the external gear 110 of 2nd Embodiment can also be added. Further, in the gear device 1 including the external gear 30 according to the modified example, the eccentric bush 120 can be used instead of the eccentric bush 44.

-The outer periphery side lubricating oil reservoir part 116 of 2nd Embodiment has an equal width dimension. However, the shape of the outer peripheral side lubricating oil reservoir 116 is not limited to the content exemplified in the second embodiment. For example, the outer peripheral side lubricating oil reservoir of the modified example has the following shape.
(A) As shown in FIG. 12, the outer peripheral-side lubricating oil reservoir 118 has a tapered shape in which the width dimension HC1 decreases from the outer teeth 112 toward the inward direction ZB1.
(B) As shown in FIG. 13, the outer peripheral side lubricating oil reservoir 119 has a shape in which the width dimension HC11 of the portion on the outer side ZB2 side is larger than the width dimension HC12 of the portion on the inner side ZB1 side.

  In the second embodiment, one lubricating oil reservoir 116, 117 is formed for each through hole 113 of the external gear 110. However, the number of the lubricating oil reservoirs 116 and 117 is not limited to the content exemplified in the second embodiment. For example, as shown in FIG. 14A, two lubricating oil reservoirs 116 and 117 of the modified example are formed for each through hole 113. Further, as shown in FIG. 14B, the outer peripheral side lubricating oil reservoir 116 is located on the bottom surface 112 </ b> B of the external tooth 112.

  -The eccentric bush 120 of 2nd Embodiment has the 1st lubricating oil reservoir part 122 and the 2nd lubricating oil reservoir part 123. FIG. However, the configuration of the eccentric bush 120 is not limited to the content exemplified in the second embodiment. For example, as shown in FIG. 14A, the eccentric bush 120 of the modified example has two third lubricating oil reservoirs 124 in addition to the lubricating oil reservoirs 122 and 123. The third lubricating oil reservoir portion 124 is located between the circumferential directions ZC of the lubricating oil reservoir portions 122 and 123. The third lubricating oil reservoir 124 is located at a portion of the eccentric bush 120 that is 90 ° away from the lubricating oil reservoirs 122 and 123 in the circumferential direction ZC.

-In the external gear 110 of 2nd Embodiment, either the outer peripheral side lubricating oil reservoir part 116 and the inner peripheral side lubricating oil reservoir part 117 can also be abbreviate | omitted.
-In the external gear 110 of 2nd Embodiment, at least one of the 1st lubricating oil pool part 36 and the 2nd lubricating oil pool part 37 of the external gear 30 of 1st Embodiment can also be added.

  In the inner bearing 90 of each embodiment, the first seal parts 95 are located on both sides of the rolling element 93 in the axial direction ZA. However, the structure of the inner side bearing 90 is not restricted to the content illustrated by each embodiment. For example, the modified inner bearing 90 has a configuration in which the first seal component 95 closer to the external gear 30 than the rolling elements 93 is omitted.

  In the outer bearing 100 of each embodiment, the second seal parts 105 are located on both sides of the rolling element 103 in the axial direction ZA. However, the structure of the outer side bearing 100 is not restricted to the content illustrated by each embodiment. For example, the modified outer bearing 100 has a configuration in which the second seal component 105 closer to the external gear 30 than the rolling elements 103 is omitted.

  -The 2nd rotation unit 40 of each embodiment has each needle bearing 41 and 42 and the eccentric bush 44 as an external-tooth support mechanism. However, the configuration of the external tooth support mechanism is not limited to the content exemplified in each embodiment. For example, the modified second rotating unit 40 does not have the second needle bearing 42 as an external tooth support mechanism. In the second rotating unit 40 of the modified example, the outer peripheral surface of the eccentric bush 44 is in contact with the inner peripheral surfaces of the through holes 33 and 113 of the external gears 30 and 110. When the external gears 30 and 110 swing and rotate, the eccentric bush 44 rotates while sliding with respect to the inner peripheral surfaces of the through holes 33 and 113.

  In addition, the second rotating unit 40 of another modified example has an annular bushing in which the needle bearings 41 and 42 are omitted, and the eccentric bushing 44 has a central axis coaxial with the central axis of the pin 43. The annular bush is fitted on the outer peripheral surface of the pin 43 so as to be rotatable with respect to the pin 43. When the external gear 30 swings and rotates, the annular bush rotates by contacting the inner peripheral surface of the through hole 33.

  -The 1st rotation unit 10 of each embodiment has the needle bearing 11 as a bearing. However, the structure of a bearing is not restricted to the content illustrated by each embodiment. For example, the first rotating unit 10 of the modified example has a double-row rolling bearing instead of a needle bearing as a bearing. In short, the bearing may be a type of bearing other than the needle bearing 11 as long as it can support the rotating shaft 20 in a state where the rotating shaft 20 can rotate with respect to the external gear 30.

  In the gear device 1 of each embodiment, the surface roughness of the outer peripheral surface 21A of the rotary shaft 20, the inner peripheral surface 50A and the outer peripheral surface 50B of the side plate 50, and the inner peripheral surface 81A of the housing 80 is relatively small. However, the relationship of the surface roughness of the gear device 1 is not limited to the content exemplified in each embodiment. In the gear device 1 according to the modified example, other surface roughnesses of the outer peripheral surface 21A of the rotary shaft 20, the inner peripheral surface 50A and the outer peripheral surface 50B of the side plate 50, and the inner peripheral surface 81A of the housing 80 correspond to other components. It may be equal to or greater than the surface roughness of the portion. That is, in the gear device 1 of the modified example, at least one of the outer peripheral surface 21A of the rotating shaft 20, the inner peripheral surface 50A and the outer peripheral surface 50B of the side plate 50, and the inner peripheral surface 81A of the housing 80 is not subjected to polishing treatment. It may be a configuration.

  -The gear apparatus 1 of each embodiment has the one external gear 30,110. However, the structure of the gear apparatus 1 is not restricted to the content illustrated by each embodiment. For example, the gear device 1 according to the modified example includes two or more external gears 30 and 110.

  The gear device 1 of each embodiment has a configuration in which the external teeth 32 and 112 of the external gears 30 and 110 directly mesh with the internal teeth 73 of the internal gear 70. However, the structure of the gear apparatus 1 is not restricted to the content illustrated by each embodiment. For example, the gear device 1 according to the modified example has a configuration in which the external gears 30 and 110 and the internal gear 70 mesh with each other via a pin.

  The gear device 1 of each embodiment has a configuration as a speed reducer in which the input element 2 is connected to the rotating shaft 20 and the output element 3 is connected to the side plate 50. However, the structure of the gear apparatus 1 is not restricted to the content illustrated by each embodiment. For example, the gear device 1 of the modified example has a configuration as a speed increasing device in which the output element 3 is connected to the rotating shaft 20 and the input element 2 is connected to the side plate 50.

  -The gear apparatus 1 of each embodiment is applied to a robot hand. However, the application example of the gear device 1 is not limited to this. For example, the gear device 1 may be applied to an in-wheel motor that drives each wheel of the vehicle. That is, you may apply the gear apparatus 1 as a reduction device of an in-wheel motor. Moreover, you may apply the gear apparatus 1 to the reduction gear of a wind power generator. In short, the present gear device can be applied to a drive device having a reduction gear.

  J1 ... center axis, JD ... center axis, ZA ... axial direction, ZB ... radial direction, ZC ... circumferential direction, HB1 ... groove depth, HB2 ... groove depth, LB ... lubricating oil, 1 ... gear device, 11 ... needle Bearing (bearing), 20 ... rotating shaft, 22 ... eccentric cam, 30 ... external gear, 31A ... end face (one end face of the external gear), 31B ... end face (the other end face of the external gear), 32 ... outside Teeth 33 ... through hole 36 ... first lubricating oil reservoir (lubricant oil reservoir), 37 ... second lubricating oil reservoir (lubricant oil reservoir), 38 ... first lubricating oil reservoir (lubricant oil reservoir) ), 39... First lubricant reservoir (lubricant reservoir), 41. First needle bearing (external tooth support mechanism), 42. Second needle bearing (external tooth support mechanism), 44. Eccentric bush (external tooth) Support mechanism), 44A ... through hole, 70 ... internal gear, 73 ... internal gear, 110 ... external gear, 111 ... inner peripheral surface, 112 ... external teeth, 112A ... tooth tip surface (a surface different from the meshing surface), 112B ... bottom surface (a surface different from the meshing surface), 113 ... through-hole, 116 ... outer side lubricating oil reservoir DESCRIPTION OF SYMBOLS 117 ... Inner peripheral side lubricating oil reservoir part, 118 ... Outer peripheral side lubricating oil reservoir part, 119 ... Outer peripheral side lubricating oil reservoir part, 120 ... Eccentric bush, 121 ... Through-hole, 122 ... First lubricating oil reservoir part (lubricating oil Reservoir), 123... Second lubricating oil reservoir (lubricating oil reservoir).

Claims (7)

An internal gear having a plurality of internal teeth formed on the inner peripheral side;
A rotary shaft disposed on the inner peripheral side of the internal gear via a gap and having an eccentric cam;
A plurality of external teeth arranged on the inner peripheral side of the internal gear and meshing with the inner teeth on the outer peripheral side, and a plurality of through holes that are spaced apart from each other in the circumferential direction of the rotary shaft and penetrate in the axial direction of the rotary shaft And an external gear that swings and rotates around the rotation center axis of the rotation shaft by the eccentric cam as the rotation shaft rotates.
An external support mechanism that is inserted into the through-hole and supports the external gear with respect to the rotation of the external gear.
The external gear includes a lubricating oil reservoir that is connected to the through hole and filled with lubricating oil between the through holes adjacent in the circumferential direction. The gear device according to claim 1, wherein the lubricating oil reservoir portion connects the through holes adjacent in the circumferential direction. The lubricating oil reservoir portion includes a groove-shaped first lubricating oil reservoir portion recessed from one end face of the external gear in the axial direction, and a groove-shaped first recess recessed from the other end face of the external gear in the axial direction. 2 lubricating oil reservoir,
The gear device according to claim 1 or 2, wherein the first lubricating oil reservoir and the second lubricating oil reservoir are alternately arranged in the circumferential direction. The gear device has one external gear,
The lubricating oil reservoir portion is formed as a groove shape recessed from an end surface of the external gear in the axial direction,
The groove depth of the lubricating oil reservoir is at least half of the axial dimension of the external gear and smaller than the axial dimension of the external gear. Gear device. Between the eccentric cam and the external gear, a bearing that supports the eccentric cam in a state in which the eccentric cam can rotate with respect to the external gear,
An outer peripheral lubricating oil reservoir that communicates the external teeth and the through hole in the radial direction of the rotary shaft, and an inner peripheral lubricating oil reservoir that communicates the inner peripheral surface of the external gear and the through hole in the radial direction. The gear device according to any one of claims 1 to 4, comprising at least one of the following. The gear device has the outer peripheral side lubricating oil reservoir,
The gear device according to claim 5, wherein the outer peripheral side lubricating oil reservoir portion is formed on a surface different from a meshing surface with the inner teeth in the outer teeth. The external tooth support mechanism has an eccentric bush in which a through hole having a center different from the center of the through hole is formed,
Between the outer teeth and the inner teeth is filled with lubricating oil,
The eccentric bush penetrates a portion on the opposite side of the center of the eccentric bush with respect to the center of the through hole in the radial direction connecting the center of the through hole and the center of the eccentric bush in the radial direction of the eccentric bush. The gear unit according to any one of claims 1 to 6, wherein a lubricating oil reservoir portion filled with lubricating oil is formed.