JP2015124792A - Gear device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gear device capable of reducing a load acting between an eccentric portion and an external gear.SOLUTION: A reduction gear 1 includes an external gear 12 relatively rotatably supported through a bearing 32 at an outer periphery of an eccentric portion 22 of a cam shaft 11, an internal gear 14 engaged with a part of the external gear 12, and a carrier 15 having a plurality of pin members 53 circumferentially arranged around an axis L1 of a shaft portion 21 of the cam shaft 11. The external gear 12 is provided with a plurality of pin holes 33 arranged in the circumferential direction around its center O2. Hole gears 34 are integrally formed on inner peripheries of the pin holes 33. Each pin member 53 includes a pin body 61, and a bearing 62 disposed on an outer periphery of the pin body 61, and a pin gear 65 is integrally formed on an outer ring of the bearing 62. Further the cam shaft 11 is provided with auxiliary gears 16, 17 engaged with the pin gear 65 integrally rotatably on the same shaft as the axis L1.

Description

  The present invention relates to a gear device.

  2. Description of the Related Art Conventionally, an eccentric oscillating type (hypocycloid type) planetary gear device is known as a gear device used in a reduction gear or the like (for example, Patent Document 1). A reduction gear using this type of gear device includes a camshaft in which a disc-shaped eccentric portion is formed on a round rod-shaped shaft portion, and an external gear provided on the outer periphery of the eccentric portion so as to be relatively rotatable via a bearing. And an internal gear fixed coaxially with the shaft portion of the camshaft, and a carrier having a plurality of pin members respectively inserted into a plurality of pin through holes provided in the external gear. Then, rotation is input to the camshaft, and the eccentric portion rotates eccentrically around the axis of the shaft portion, so that the external gear is swung (revolved) in a manner of drawing a hypocycloid curve, while the teeth of the internal gear and the external gear are The motor rotates according to the number difference, and the rotation is output from the carrier.

Japanese Patent Laid-Open No. 2012-223081

  However, as described above, the external gear rotates while being oscillated by the eccentric rotation of the eccentric portion, so that a relatively large load acts on the external gear from the eccentric portion. For this reason, the eccentric portion and the external gear are easily damaged, and particularly in the configuration in which the bearing is provided between the eccentric portion and the external gear as in the conventional case, there is a problem that the bearing is easily damaged.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide a gear device that can reduce a load acting between an eccentric portion and an external gear.

  A gear device that solves the above-described problem has an axis as a reference axis, is rotatable around the reference axis, and is provided with an eccentric portion having an axis at a position offset by a predetermined amount with respect to the reference axis. An eccentric member, an internal gear arranged coaxially with the reference axis, an external gear provided in the eccentric portion and meshing with the internal gear while being oscillated by the rotation of the eccentric member, and around the reference axis And a carrier having a plurality of pin members arranged side by side in the circumferential direction, and a plurality of pin passages arranged in the circumferential direction and inserted into the external gear. A hole is formed, and is fixed to each pin through hole, provided with a through hole gear having a plurality of internal teeth, and provided around each pin member so as to be relatively rotatable with each pin member. Plural meshing with part of internal teeth A pin gear having external teeth; and an auxiliary gear having a plurality of external teeth that are provided coaxially with the reference axis so as to rotate integrally with the eccentric member and mesh with a part of each external tooth of the pin gear. This is the gist.

  According to the above configuration, the pin gear meshes with the through-hole gear and the pin gear. For example, when the internal gear is fixed and rotation is input to the eccentric member, the torque in the same direction from the through-hole gear and the auxiliary gear, respectively. Receive. Therefore, when rotation is input to the eccentric member, torque is transmitted to the external gear not only from the eccentric portion but also from the auxiliary gear via the pin gear. Thereby, the load which acts between an eccentric part and an external gear can be reduced.

  In the above gear device, the auxiliary gear adjusts the position of the center of gravity of the auxiliary gear so that the combined center of gravity of the center of gravity of the auxiliary gear and the center of gravity of the external gear is positioned on the reference axis. It is preferable to provide a part.

According to the above configuration, the combined center of gravity obtained by combining the center of gravity of the external gear and the center of gravity of the auxiliary gear is positioned on the same axis as the reference axis, so that it is possible to suppress the occurrence of vibration associated with the swinging of the external gear.
In the gear device, the eccentric member includes a plurality of the eccentric portions, and the outer gears that mesh with the internal gear while being oscillated and rotated by the rotation of the eccentric member are respectively provided in the plurality of eccentric portions. Preferably, the plurality of eccentric portions are provided such that one and the other of the plurality of external gears are shifted from each other by more than 90 ° around the reference axis.

  Here, in the conventional configuration in which the through-hole gear and the pin gear are not provided, the rotation (torque) transmitted from the external gear to the carrier is caused by the pin through-hole pushing the pin member in the circumferential direction by the rotation of the external gear. Most of it is transmitted. That is, when the inner peripheral surface of the pin through hole comes into contact with the pin member on the rear side in the rotation direction of the carrier, a pressing force in a direction substantially along the rotation direction acts on the pin member from the pin through hole. However, in the pin through hole in the vicinity of the meshing position between the external gear and the internal gear, the pin member comes into contact with the side in the rotational direction and hardly presses the pin member. Therefore, the load applied to some of the pin members is increased according to the meshing position of the external gear and the internal gear, so that the strength required for the pin member is increased, and for example, it is difficult to downsize the pin member. Become.

  In this regard, according to the above configuration, the through-hole gear meshes with the pin gear on the side in the carrier rotation direction, and the tangential direction at the meshing position with the through-hole gear is close to an angle parallel to the rotation direction. When an external gear applies a pressing force in the rotational direction corresponding to rotation to the pin gear via the hole gear, the pin gear is passed from the other external gear. A pressing force in the rotational direction corresponding to the rotation is applied through the hole gear. Here, since the one external gear and the other external gear are provided to be shifted from each other by more than 90 ° around the reference axis, the rotational direction acting on the pin gear from the one and other external gears Will cause the pin gears to rotate in opposite directions. Therefore, the pressing force in the rotational direction that acts on the pin gear from one and the other external gears is not absorbed by the rotation of the pin gear, but acts on the pin member (carrier) via the pin gear. . Thereby, since the number of pin members contributing to torque transmission increases, it can suppress that a big burden is added to some pin members according to the meshing position of an external gear and an internal gear. Therefore, the strength required for each pin member can be reduced, and the size can be reduced.

  According to the present invention, the load acting between the eccentric part and the external gear can be reduced.

Sectional drawing along the axial direction of the reduction gear of 1st Embodiment. Sectional drawing orthogonal to the axial direction which passes between between the external gear and the auxiliary gear in the reduction gear of 1st Embodiment (AA sectional drawing of FIG. 1). Sectional drawing orthogonal to the axial direction which passes between between the auxiliary gears and the 1st plate in the reduction gear of 1st Embodiment (BB sectional drawing of FIG. 1). Sectional drawing along the axial direction of the reduction gear of 2nd Embodiment. (A) is sectional drawing (CC sectional drawing of FIG. 4) orthogonal to the axial direction which passes between between the external gear and the auxiliary gear in the reduction gear of 2nd Embodiment, (b) is an expanded sectional view of the pin member vicinity. Figure. The schematic diagram which shows the pressing force which acts on each pin member of the reduction gear of 2nd Embodiment.

(First embodiment)
Hereinafter, 1st Embodiment of a gear apparatus is described according to drawing.
A reduction gear 1 as a gear device shown in FIG. 1 and FIG. 2 is configured using an eccentric rocking type (hypocycloid type) planetary gear mechanism. The speed reducer 1 includes a camshaft 11 as an eccentric member that is arranged coaxially with a motor shaft (not shown) of the motor 2 and is rotationally driven. The speed reducer 1 includes an external gear 12 that is rotatably provided on the camshaft 11, an internal gear 14 that meshes with a part of the external gear 12, and a carrier 15 that outputs rotation input to the camshaft 11. And. Further, the speed reducer 1 includes two auxiliary gears 16 and 17 provided so as to be rotatable together with the camshaft 11. In the following description, the motor 2 side (left side in FIG. 1) of the reduction gear 1 is defined as one axial end side, and the opposite side (right side in FIG. 1) is defined as the other axial end side.

  Specifically, the camshaft 11 includes a round bar-shaped shaft portion 21 disposed coaxially with the motor shaft, and a disc-shaped eccentric portion 22 provided in the middle of the shaft portion 21. The eccentric portion 22 has an axis L2 at a position eccentric by a predetermined amount with respect to an axis L1 as a reference axis of the shaft portion 21. The camshaft 11 is connected such that one axial end portion of the shaft portion 21 is coaxially connected to a motor shaft (not shown) so as to be integrally rotatable.

  The external gear 12 is formed in a disk shape. On the outer peripheral surface of the external gear 12, a plurality of external teeth 12a protruding outward in the radial direction are formed. A central hole 31 penetrating in the axial direction is formed in the center of the external gear 12. And the external gear 12 is provided in the outer periphery of the eccentric part 22 through the bearing 32 provided in the center hole 31 so that relative rotation is possible. The center of gravity of the external gear 12 is located on the side where the axis L2 of the eccentric portion 22 is eccentric with respect to the axis L1 of the shaft portion 21 (the upper side in FIGS. 1 and 2).

  A plurality of pin through-holes 33 are formed around the center O2 at intervals in the circumferential direction at a portion between the central hole 31 and the external teeth 12a in the external gear 12. The pin through-hole 33 is a circular hole formed in a round hole shape, and is arranged on a circle centered on the center O2 of the external gear 12. A plurality of internal teeth projecting radially inward are formed on the inner peripheral surface of the pin through-hole 33 as the through-hole internal teeth 34a over the entire axial direction. That is, the through-hole gear 34 is integrally formed in the pin through-hole 33 in the external gear 12 of the present embodiment.

  The internal gear 14 is formed in a cylindrical shape. A plurality of internal teeth 14 a projecting radially inward are formed at the axially central portion of the inner peripheral surface of the internal gear 14. The center O1 of the internal gear 14 is arranged coaxially with the axis L1 of the shaft portion 21, and a part of the internal teeth 14a and a part of the external teeth 12a mesh with each other. The number of teeth of the inner teeth 14a is set to be larger than the number of teeth of the outer teeth 12a. Further, in the external teeth 12a and the internal teeth 14a of the present embodiment, flat tooth involute tooth shapes each having a tooth line parallel to the axis are employed. As shown in FIG. 1, the internal gear 14 is formed with cylindrical extending portions 41 and 42 projecting on both sides in the axial direction. A cylindrical housing member (not shown) for housing the motor 2 is connected to the extending portion 41 on the one axial end side of the internal gear 14, and the extending portion 42 on the other axial end side is connected to the extending portion 42 on the other axial end side. A disk-shaped lid member (not shown) is connected.

  The carrier 15 is inserted through the pin through hole 33, the first plate 51 disposed on one end side in the axial direction of the external gear 12, the second plate 52 disposed on the other end side in the axial direction of the external gear 12. And a pin member 53 that connects the first plate 51 and the second plate 52 around the axis L1 as the reference axis so as to be integrally rotatable.

  The first plate 51 is formed in a disc shape. A through hole 54 is formed in the center of the first plate 51. The first plate 51 includes a bearing 55 a provided between the outer periphery of the first plate 51 and the extending portion 41 on one end side in the axial direction of the internal gear 14, and the through hole 54 and the outer periphery of the shaft portion 21 of the camshaft 11. A bearing 55b provided therebetween is supported so as to be rotatable relative to the internal gear 14 and the camshaft 11.

  The second plate 52 is formed in a disc shape. A through hole 56 is formed in the center of the second plate 52. The second plate 52 includes a bearing 57 a provided between the outer periphery of the second plate 52 and the extending portion 42 on the other axial end side of the internal gear 14, and the outer periphery of the through hole 56 and the shaft portion 21 of the camshaft 11. Are supported so as to be rotatable relative to the internal gear 14 and the camshaft 11. An output member such as a wheel of a wheel (not shown) is connected to the other axial end of the second plate 52.

  As shown in FIGS. 1 and 2, each pin member 53 includes a pin main body 61 formed in a columnar shape, and a bearing 62 provided on the outer periphery of the pin main body 61. A needle bearing is adopted as the bearing 62 of the present embodiment. The length of the bearing 62 along the axial direction is set to be longer than the length of the external gear 12 along the axial direction, and both end portions in the axial direction protrude from the pin through-holes 33. A plurality of external teeth projecting radially outward are formed on the outer peripheral surface of the bearing 62 (outer ring) as pin external teeth 65a over the entire axial direction. That is, the pin gear 65 is integrally formed on the outer ring of the bearing 62 of the present embodiment. The number of teeth of the pin outer teeth 65a is set to be smaller than the number of teeth of the through-hole inner teeth 34a. Further, in each of the through-hole inner teeth 34a and each pin outer tooth 65a of the present embodiment, a flat tooth involute tooth profile whose teeth are parallel to the axis is adopted.

  Each pin member 53 is disposed on a circle centered on the axis L1 of the camshaft 11 in a state of being inserted into the pin through-hole 33 of the external gear 12, and the first and second bolts 66 and 67 are used as first and second bolts. The plates 51 and 52 are connected so as to be rotatable together. Thereby, a part of pin external tooth 65a and a part of through-hole internal tooth 34a mesh. Specifically, the relationship between the meshing position of the pin gear 65 with respect to the through-hole gear 34 and the center of the pin through-hole 33 is substantially the same as the relationship between the meshing position of the external gear 12 with respect to the internal gear 14 and the center O1 of the internal gear 14. The phase relationship is 180 ° shifted.

  As shown in FIGS. 1 and 3, the auxiliary gears 16 and 17 are disposed on both sides of the external gear 12 in the axial direction, and are each formed in a disk shape. Through holes 71 and 72 are formed in the centers of the auxiliary gears 16 and 17, respectively. Key grooves 73 and 74 having a quadrangular cross section are formed on the inner periphery of the through holes 71 and 72. On the other hand, the shaft portion 21 of the camshaft 11 is formed with key grooves 75 and 76 facing the key grooves 73 and 74. Note that the key grooves 75 and 76 of the present embodiment are formed at positions shifted from each other by approximately 180 ° around the axis L1. A square columnar key member 77 that fits in the key grooves 73 and 75 is inserted between the auxiliary gear 16 and the shaft portion 21, and a key groove 74 is inserted between the auxiliary gear 17 and the shaft portion 21. , 76 is inserted into a quadrangular columnar key member 78. Thus, the auxiliary gears 16 and 17 are connected to the camshaft 11 so as to be integrally rotatable. A plurality of external teeth protruding radially outward are formed on the outer peripheral surfaces of the auxiliary gears 16 and 17 as auxiliary external teeth 16a and 17a, respectively. Here, the specifications of the internal gear 14, the external gear 12, the through-hole gear 34, the pin gear 65, and the auxiliary gears 16 and 17 are set so as to satisfy the following equation.

(Z1-Z2) / m1 = (Z3-Z4) / m2 (1)
Z3 = Z5 (2)
"Z1" is the number of teeth of the internal gear 14, "Z2" is the number of teeth of the external gear 12, "Z3" is the number of teeth of the through-hole gear 34, "Z4" is the number of teeth of the pin gear 65, and "Z5" Indicates the number of teeth of the auxiliary gears 16 and 17, respectively. “M1” indicates a module of the internal gear 14 and the external gear 12, and “m2” indicates a module of the through-gear 34, the pin gear 65, and the auxiliary gears 16 and 17, respectively.

  Further, the auxiliary gears 16 and 17 are formed with hollow portions 81 and 82 as arc-shaped groove-shaped gravity center adjusting portions extending in the circumferential direction. The cavities 81 and 82 are formed in regions of the auxiliary gears 16 and 17 on the side where the axis L2 of the eccentric portion 22 is eccentric with respect to the axis L1 of the shaft portion 21. As a result, the center of gravity of the auxiliary gears 16 and 17 is located on the opposite side of the axis L2 of the eccentric portion 22 with respect to the axis L1 of the shaft portion 21, and the center of gravity of the auxiliary gears 16 and 17 and the center of gravity of the external gear 12 described above. And the combined center of gravity is positioned on the axis L1.

Next, the operation (action) of the actuator of this embodiment will be described.
When the camshaft 11 is rotated, the external gear 12 is moved (revolved) in such a manner that the locus of the external teeth 12a draws a hypocycloid curve by moving the meshing position with the internal gear 14 in the circumferential direction. It rotates (rotates around the center O2) according to the number of teeth difference between the teeth 12a and the internal teeth 14a. At this time, the meshing position of the through-hole gear 34 and the pin gear 65 is such that the outer ring of each bearing 62 rotates around the center of the pin member 53, so It moves in the circumferential direction while maintaining the relationship that is in the opposite phase to the meshing position with the gear 14. Then, the rotation of the external gear 12 is transmitted to each pin member 53, whereby the rotation of the camshaft 11 is reversed while being decelerated and output from the carrier 15. Specifically, in the external gear 12, the through-hole gear 34 meshes with the pin gear 65 on the rear side in the rotation direction of the carrier 15, and the tangential direction at the meshing position with the pin gear 65 is relative to the rotation direction of the carrier 15. The rotation of the rotation is transmitted to the pin member 53 by pressing the pin member 53 in the rotation direction through the through-hole gear 34 having a substantially right angle.

  Here, when the camshaft 11 rotates clockwise, the pin gear 65 receives torque from the through-hole gear 34 according to the swing of the external gear 12 and rotates counterclockwise, that is, in the direction opposite to the camshaft 11. To do. Further, the pin gear 65 receives torque from the auxiliary gears 16 and 17 in accordance with the rotation of the camshaft 11 and rotates counterclockwise. That is, the pin gear 65 receives torque in the same direction from the through-hole gear 34 and the auxiliary gears 16 and 17. Therefore, when the camshaft 11 rotates, torque is transmitted to the external gear 12 not only from the eccentric portion 22 but also from the auxiliary gears 16 and 17 via the pin gear 65. Thereby, the external gear 12 of the present embodiment rotates while swinging due to the eccentric rotation of the eccentric portion 22 and the rotation of the auxiliary gears 16 and 17.

Next, the effect of this embodiment will be described.
(1) The through-hole gear 34 is formed in each pin through-hole 33, the pin gear 65 is formed in the bearing 62 of the pin member 53, and the auxiliary gears 16, 17 meshing with the pin gear 65 are integrally rotated with the camshaft 11. Since the external gear 12 is provided, the external gear 12 rotates while being oscillated by the eccentric rotation of the eccentric portion 22 and the rotation of the auxiliary gears 16 and 17. Thereby, the load which acts between the eccentric part 22 and the external gear 12 can be reduced, and damage to the bearing 32 can be reduced.

  (2) The position of the center of gravity of the auxiliary gears 16 and 17 is adjusted so that the combined center of gravity obtained by combining the auxiliary gears 16 and 17 with the center of gravity of the auxiliary gears 16 and 17 and the center of gravity of the external gear 12 is positioned on the axis L1. Since the hollow portions 81 and 82 to be formed are formed, it is possible to suppress the occurrence of vibration accompanying the swinging of the external gear 12.

(Second Embodiment)
Next, a second embodiment will be described with reference to the drawings. For convenience of explanation, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

  As shown in FIGS. 4, 5 (a), and 5 (b), another eccentric portion 91 is formed adjacent to the eccentric portion 22 in the camshaft 11 of the present embodiment. The eccentric portion 91 has the same shape as the eccentric portion 22, is eccentric by a predetermined amount with respect to the axis L 1 of the shaft portion 21, and has an axis line at a position displaced about 180 ° from the axis L 2 of the eccentric portion 22 around the axis L 1. L3.

  In addition to the external gear 12, the speed reducer 1 includes an external gear 93 provided on the outer periphery of the eccentric portion 91 via a bearing 92 so as to be relatively rotatable. The external gear 93 is formed in the same shape as the external gear 12, and includes a plurality of external teeth 93 a, a center hole 94, a pin through hole 95, a plurality of through hole internal teeth 96 a, and a through hole gear 96. Yes.

  That is, the centers O2, O3 of the two external gears 12, 93 are positioned on the axis lines L2, L3 of the eccentric portions 22, 91, respectively, and the two external gears 12, 93 are connected to the axis line L1 ( Arranged at positions rotated by approximately 180 ° around the center O1) of the internal gear 42. Further, the relationship between the meshing position of the pin gear 65 with respect to the through-hole gear 96 and the center of the pin through-hole 95 is shifted by approximately 180 ° from the relationship between the meshing position of the external gear 93 with respect to the internal gear 14 and the center O1 of the internal gear 14. The relationship is antiphase. As a result, the pin gear 65 (the pins positioned on the upper side and the lower side in FIG. 6) have a tangential direction at the meshing position of the through-hole gears 34 and 96 and the pin gear 65 close to the rotation direction of the carrier 15. The through-hole gears 34 and 96 are engaged with the gears 65y and 65z from both the inner side (axis L1 side) and the outer side (opposite side of the axis L1) of each pin member 53 arranged in an annular shape. In addition, the cavity parts 81 and 82 are not formed in the auxiliary gears 16 and 17 of this embodiment.

Next, the operation (action) of the actuator of this embodiment will be described.
The speed reducer 1 according to the present embodiment operates in the same manner as in the first embodiment, and the external gears 12 and 93 rotate while swinging due to the eccentric rotation of the eccentric portions 22 and 91 and the rotation of the auxiliary gears 16 and 17. To do. Then, the rotation of the external gears 12, 93 is transmitted to each pin member 53, whereby the rotation of the camshaft 11 is reversed while being decelerated and output from the carrier 15. That is, when the camshaft 11 rotates clockwise, the carrier 15 rotates counterclockwise.

  Specifically, as shown in FIG. 6, the external gears 12 and 93 are configured so that the through-hole gears 34 and 96 mesh with the pin gear 65 on the rear side in the rotation direction of the carrier 15 and at the meshed position with the pin gear 65. By pressing the pin member 53 in the rotational direction independently through the through-hole gears 34 and 96 (pin through-holes 33 and 95) whose tangential direction is close to a right angle with respect to the rotational direction of the carrier 15. The rotation of the rotation is transmitted to the pin member 53. Specifically, as indicated by a thick arrow in FIG. 6, a pressing force in the rotational direction acts on the pin member 53 (pin gear 65x) alone from the through-hole gear 34x located on the right side of the external gear 12, and the external gear 12 A pressing force in the rotational direction acts solely on the pin member 53 (pin gear 65x) from the through-hole gear 96x located on the left side of the gear 93.

  Further, in the pin through holes 33 and 95 in the vicinity of the meshing position between the external gears 12 and 93 and the internal gear 14, the external gears 12 and 93 of the present embodiment cooperate with each other so that the through gears 34 and 96 are connected. The pin is engaged with the pin gear 65 via the through-hole gears 34 and 96 that mesh with the side in the rotational direction and whose tangential direction at the meshing position with the pin gear 65 is an angle close to the rotational direction of the carrier 15. By rotating the member 53 in the rotation direction, rotation of the rotation is transmitted to the pin member 53.

  Specifically, as indicated by a thick arrow in FIG. 6, a pressing force in the rotational direction acts on the pin gear 65y from the through-hole gear 34y located on the upper side of the external gear 12 at the position on the axis L1 side. At this time, a pressing force in the rotational direction acts on the pin gear 65y from the through-hole gear 96y located on the upper side of the external gear 93 at a position opposite to the axis L1. Further, a pressing force in the rotational direction acts on the pin gear 65z from the through-hole gear 34z located on the lower side of the external gear 12 at a position opposite to the axis L1. At this time, a pressing force in the rotational direction acts on the pin gear 65z from the lower through-hole gear 96z in the external gear 93 at a position on the axis L1 side. That is, the pressing force in the rotational direction acting on the pin gear 65 from the external gears 12 and 93 causes the pin gear 65 to rotate in opposite directions. Therefore, the pressing force in the rotational direction acting on the pin gears 65 located on the upper side and the lower side in FIG. 6 from the external gears 12 and 93 is not absorbed by the rotation of the pin gear 65, and is transmitted via the pin gear 65. It acts on the pin member 53 (carrier 15). As a result, all the pin members 53 contribute to torque transmission from the external gears 12 and 93 to the carrier 15.

Next, the effect of this embodiment will be described. In addition to the effect (1) of the first embodiment, the present embodiment has the following effect.
(3) The through-hole gears 34 and 96 are formed in the pin through-holes 33 and 95, the pin gear 65 is formed in the bearing 62 of the pin member 53, and the external gears 12 and 93 are arranged around the axis L1 of the camshaft 11. Since the number of pin members 53 involved in torque transmission increases as described above by arranging them at positions rotated by 180 ° relative to each other, the burden on each pin member 53 can be reduced. Therefore, the strength required for each pin member 53 can be reduced, and the size can be reduced.

In addition, each said embodiment can also be implemented in the following aspects which changed this suitably.
In the first embodiment, the hollow portions 81 and 82 are formed in the auxiliary gears 16 and 17, respectively, and a portion thereof is reduced in weight so that the combined center of gravity of the external gear 12 and the auxiliary gears 16 and 17 is positioned on the axis L1. I tried to do it. However, the present invention is not limited to this. For example, the weight of the auxiliary gears 16 and 17 may be provided so that the combined center of gravity is positioned on the axis L1. The auxiliary gears 16 and 17 do not have to be provided with the center of gravity adjustment unit. In the second embodiment, the auxiliary gears 16 and 17 may be provided with a center of gravity adjustment unit.

  In the second embodiment, the camshaft 11 is formed so that the axis lines L1 and L2 of the eccentric parts 22 and 91 are displaced from each other by about 180 ° around the axis line L1 of the shaft part 21, but the present invention is not limited thereto, and at least the axis line L1 It may be 180 ° or less as long as it is displaced more than 90 ° around.

  In each of the above embodiments, the external teeth 12a and 93a, the internal teeth 14a, the through-hole internal teeth 34a and 96a, and the pin external teeth 65a are flat teeth. . In this case, it is preferable that the external teeth 12a and 93a, the internal teeth 14a, the through-hole internal teeth 34a and 96a, and the pin external teeth 65a are inclined teeth in which the streaks are twisted in the same direction. Thereby, the thrust force generated at the meshing position of the external teeth 12a, 93a and the internal teeth 14a and the thrust force generated at the meshing position of the through-hole internal teeth 34a, 96a and the pin external teeth 65a are mutually connected. Reverse. Therefore, the thrust force that acts on the external gears 12 and 93 from each meshing position can be offset, and the external gears 12 and 93 need not be supported from the axial direction.

In each embodiment described above, the external teeth 12a and 93a, the internal teeth 14a, the through-hole internal teeth 34a and 96a, and the pin external teeth 65a may be, for example, a cycloid tooth profile.
In each of the above embodiments, the external gears 12, 93, the internal gear 14, the through-hole gears 34, 96, the pin gear 65, and the auxiliary gears 16, 17 may be configured as shift gears. In this case, it is necessary to make the shift coefficients of the external gears 12 and 93 and the pin gear 65 coincide with each other and make the shift coefficients of the internal gear 14 and the through-hole gears 34 and 96 match each other. The shift coefficients of the auxiliary gears 16 and 17 are the same as the shift coefficients of the external gears 12 and 93 and the pin gear 65, and have opposite signs. As an example, the shift coefficient of the external gears 12, 93 and the pin gear 65 is “0.4”, the shift coefficient of the internal gear 14 and the through-hole gears 34, 96 is “0”, and the shift coefficient of the auxiliary gears 16, 17 is It can be “−0.4”.

  In each of the above embodiments, the pin members 53 adjacent in the circumferential direction are alternately provided on the inner side in the radial direction and the outer side in the radial direction, and the through-hole gears 34 and 96 adjacent in the circumferential direction are provided according to the pin member 53. It may be provided alternately on the radially inner side and on the radially outer side. In this case, for example, the auxiliary gear 16 arranged on one end side in the axial direction, the through-hole gears 34 and 96 arranged on the radially inner side, the pin gear 65, the external gears 12 and 93, The auxiliary gear 17 disposed between the gear 14 and on the other end side in the axial direction, the through-hole gears 34 and 96 disposed on the outer side in the radial direction, the pin gear 65, the external gears 12 and 93, and the internal gear. 14, it is necessary to satisfy the relationship of the specifications shown in the above equations (1) and (2).

  In each of the above embodiments, the bearings 32 and 92 are not interposed between the eccentric parts 22 and 91 and the external gears 12 and 93, and the center holes 31 and 94 of the external gears 12 and 93 are the outer circumferences of the eccentric parts 22 and 91. They may be directly fitted to each other so as to be relatively rotatable.

  In each of the above embodiments, the camshaft 11 includes an eccentric member (eccentric portions 22, 91) arranged coaxially with the external gears 12, 93, and a shaft that integrally rotates the eccentric member coaxially with the internal gear 14. You may divide into. In this case, the reduction gear 1 may not be provided with a shaft, and for example, the motor shaft may be coupled to the eccentric member so as to be integrally rotatable.

  In each of the above embodiments, the through-hole internal teeth 34a and 96a are not integrally formed on the inner peripheral surfaces of the pin through-holes 33 and 95, and a through-hole gear made of another member is fixed to the pin through-holes 33 and 95. Good. Similarly, the pin outer teeth 65a may not be formed integrally with the outer ring of the bearing 62, and a pin gear made of another member may be fixed to the outer ring.

  In the first embodiment, the speed reducer 1 may have two or more external gears, and in the second embodiment, the speed reducer 1 may have three or more external gears. Moreover, in each said embodiment, it is good also as a structure with which the reduction gear 1 is equipped with only one auxiliary gear, or three or more.

  In each of the above-described embodiments, the gear device is used as the speed reducer 1. However, for example, the gear device may be used as a speed increaser that inputs rotation to the carrier 15 and outputs increased rotation from the camshaft 11.

  DESCRIPTION OF SYMBOLS 1 ... Reduction gear, 11 ... Cam shaft (eccentric member), 12, 93 ... External gear, 12a, 93a ... External tooth, 14 ... Internal gear, 14a ... Internal gear, 15 ... Carrier, 16, 17 ... Auxiliary gear, 16a , 17a ... auxiliary external teeth, 22, 91 ... eccentric part, 33, 95 ... pin through hole, 34, 96 ... through hole gear, 34a, 96a ... through hole internal tooth, 53 ... pin member, 65 ... pin gear, 65a ... pin external teeth, 81, 82 ... cavity (center of gravity adjustment), L1-L3 ... axis, O1-O3 ... center.

Claims (3)

An eccentric member having an axis as a reference axis, rotatable around the reference axis, and provided with an eccentric portion having an axis at a position eccentric from the reference axis by a predetermined amount;
An internal gear disposed coaxially with the reference axis;
An external gear that is provided in the eccentric portion and that meshes with the internal gear while oscillating by rotation of the eccentric member;
A carrier having a plurality of pin members arranged around the reference axis and arranged side by side in the circumferential direction;
The external gear is a gear device that is arranged side by side in the circumferential direction and has a plurality of pin through holes into which the pin member is inserted,
A through-hole gear fixed to each pin through-hole and having a plurality of internal teeth;
A pin gear having a plurality of external teeth provided around the pin members so as to be relatively rotatable with the pin members and meshing with a part of the internal teeth;
A gear device comprising an auxiliary gear having a plurality of external teeth that are provided coaxially with the reference axis so as to rotate integrally with the eccentric member and mesh with a part of each external tooth of the pin gear. The gear device according to claim 1, wherein
The auxiliary gear includes a center-of-gravity adjustment unit that adjusts the position of the center of gravity of the auxiliary gear so that a composite center of gravity obtained by combining the center of gravity of the auxiliary gear and the center of gravity of the external gear is positioned on the reference axis. A gear device characterized by the above. The gear device according to claim 1 or 2,
The eccentric member is provided with a plurality of the eccentric portions,
The plurality of eccentric portions are respectively provided with the external gears that mesh with the internal gear while being swung and rotated by the rotation of the eccentric member,
The gear unit, wherein the plurality of eccentric portions are provided such that one of the plurality of external gears and the other one are shifted from each other by more than 90 ° around the reference axis.