JP2011229197A - Rotary actuator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a small rotary actuator capable of rough rotation control when driving a driving object.SOLUTION: A ring gear 50 has an internal tooth 51 at an internal edge and is fixed so as to be coaxial to an input shaft. A sun gear 60 has a columnar projection 61 projecting from one face in a plate thickness direction, and an external tooth 62 that is engaged with the internal tooth 51, is provided eccentrically in a relatively rotatable manner with respect to the input shaft, and rotates and revolves when the input shaft rotates. An output shaft 70 has a disk 72 where a hole 73 into which the projection 61 can go is formed, wherein a rotation component of the sun gear 70 is transferred when an inner wall of the disk 72 with the hole 73 formed is pushed against an outer wall of the projection 61. The hole 73 is formed in the shape of a circle long in a predetermined direction such that the external shape of the hole 73 almost matches with an outer edge of a locus when a virtual circle 100 having a diameter larger than the external diameter of the projection 61 is subjected to a prescribed amount of movement in the circumferential direction of the disk 72.

Description

  The present invention relates to a rotary actuator that combines an electric motor and a speed reducer.

  2. Description of the Related Art Conventionally, in an automobile shift range switching device, a shift range selected by a driver is detected by an electronic control unit (hereinafter referred to as “ECU”), and a rotary actuator is controlled in accordance with the detected value, whereby automatic shifting is performed. A shift-by-wire system that switches the shift range of a machine is known (see, for example, Patent Document 1). This rotary actuator is provided with a speed reducer in order to decelerate the rotational output of the electric motor and output it to a detent mechanism as a drive target. The speed reducer has a sun gear that is eccentrically provided on an input shaft that is rotationally driven by an electric motor, and an output shaft that is formed with a hole portion into which a cylindrical protrusion protruding from the sun gear can enter. With this configuration, when the input shaft rotates, the sun gear rotates and revolves, and the rotation component of the sun gear is transmitted to the output shaft.

  In this rotary actuator, the shape of the hole formed in the output shaft is a perfect circle, and the diameter thereof is set in consideration of the outer diameter of the sun gear protrusion and the eccentric amount of the sun gear with respect to the input shaft. . Actually, there is a backlash between the sun gear (projection part) and the output shaft (hole part) due to the dimensional variation of each member, but this backlash is set to be as small as possible. When the backlash between the sun gear and the output shaft is small, the suction range of the detent mechanism that is rotationally driven by the output shaft is narrowed. Therefore, in this rotary actuator, high accuracy is required for rotation control when driving the detent mechanism.

JP 2005-282601 A

  Therefore, for example, if the backlash between the sun gear and the output shaft is increased by making the diameter of the hole portion of the output shaft sufficiently larger than the outer diameter of the protruding portion, the suction range of the detent mechanism can be widened. Rough rotation control of the rotary actuator becomes possible. However, since the hole is a perfect circle, increasing the diameter of the hole increases the size of the output shaft. As a result, there arises a problem that the size of the rotary actuator is increased.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a small rotary actuator capable of rough rotation control when driving an object to be driven.

  The invention described in claim 1 includes a housing, an input shaft, an electric motor, a ring gear, a sun gear, and an output shaft. The input shaft is rotatably supported by the housing. The electric motor is accommodated in the housing and rotationally drives the input shaft. The ring gear is formed in an annular shape, has internal teeth formed at the inner edge, and is fixed to the housing so as to be coaxial with the input shaft. The sun gear is formed in a disk shape and meshes with a cylindrical protrusion formed so as to protrude in the plate thickness direction from a position radially away from the center of one surface and the inner teeth of the ring gear. It has external teeth formed on the outer edge portion. The sun gear is provided eccentrically so as to be rotatable relative to the input shaft. When the input shaft rotates, the outer teeth rotate and revolve inside the ring gear while meshing with the inner teeth of the ring gear. The output shaft has a disk part in which a hole part into which the protruding part of the sun gear can enter is formed. Further, the output shaft is rotatably supported by the housing so as to be coaxial with the input shaft, and the rotation component of the sun gear is transmitted by the inner wall of the disk portion in which the hole is formed being pushed against the outer wall of the protruding portion.

  In the present invention, when the hole portion is viewed from the axial direction of the output shaft, the outer shape is “the locus when a virtual circle having a diameter larger than the outer diameter of the protruding portion moves a predetermined amount in the circumferential direction of the disk portion. It is formed in a circular shape that is long in a predetermined direction so as to substantially coincide with the “outer edge end”. According to this configuration, a play having a predetermined size can be formed between the outer wall of the projecting portion of the sun gear and the inner wall of the disk portion in which the hole portion is formed. As a result, rough rotation control can be performed when the drive target is driven by the rotary actuator.

Further, according to the above configuration, the radial width of the disk portion of the outer shape of the hole portion is smaller than the circumferential width of the disk portion. Thereby, the outer diameter of the disk part in which a hole part is formed can be made small. Therefore, the physique of the output shaft can be reduced, and as a result, the physique of the rotary actuator can be reduced.
As described above, the rotary actuator according to the present invention does not cause an increase in the size of the physique while enabling the drive of the drive target by rough rotation control.

  In the invention described in claim 2, a plurality of the hole portions are formed in the circumferential direction of the disk portion. A plurality of protrusions are formed in the circumferential direction of the sun gear in correspondence with the hole portions. Thereby, the rotation component of the sun gear can be smoothly and efficiently transmitted to the output shaft.

  The invention described in claim 3 is provided with a housing, an input shaft, an electric motor, a ring gear, a sun gear, and an output shaft, similarly to the invention described in claim 1. The input shaft is rotatably supported by the housing. The electric motor is accommodated in the housing and rotationally drives the input shaft. The ring gear is formed in an annular shape, has internal teeth formed at the inner edge, and is fixed to the housing so as to be coaxial with the input shaft. In the present invention, the sun gear is formed in a disk shape, and includes a hole portion formed at a position spaced apart from the center by a predetermined distance in the radial direction, and external teeth formed on the outer edge portion so as to mesh with the inner teeth of the ring gear. Have. The sun gear is provided eccentrically so as to be rotatable relative to the input shaft. When the input shaft rotates, the outer teeth rotate and revolve inside the ring gear while meshing with the inner teeth of the ring gear. The output shaft has a disk part formed with a cylindrical protrusion that protrudes in the thickness direction from the surface on the sun gear side so as to be able to enter the hole of the sun gear. The output shaft is rotatably supported by the housing so as to be coaxial with the input shaft, and the sun gear rotation component is transmitted by the inner wall of the sun gear having a hole formed pushing the outer wall of the protruding portion.

  In the present invention, when viewed from the axial direction of the sun gear, the outer shape of the hole is “the outer edge of the locus when a virtual circle having a diameter larger than the outer diameter of the protruding portion moves a predetermined amount in the circumferential direction of the sun gear. It is formed in a long circle in a predetermined direction so as to substantially coincide with the “end”. According to this configuration, a play having a predetermined size can be formed between the inner wall of the sun gear in which the hole portion is formed and the outer wall of the protruding portion of the disk portion. As a result, as in the first aspect of the invention, rough rotation control can be performed when the driven object is driven by the rotary actuator.

Moreover, according to the above-mentioned structure, the radial width of the sun gear of the outer shape of the hole is smaller than the circumferential width of the sun gear. Thereby, the outer diameter of the sun gear in which the hole is formed can be reduced. As a result, the size of the rotary actuator can be reduced.
As described above, in the rotary actuator according to the present invention, as in the first aspect of the present invention, the driving target can be driven by rough rotation control, but the size of the physique is not increased.

  In the invention according to claim 4, a plurality of holes are formed in the circumferential direction of the sun gear. In addition, a plurality of protrusions are formed in the circumferential direction of the disk portion so as to correspond to the hole portions. Thereby, like the invention of Claim 2, the autorotation component of a sun gear can be smoothly and efficiently transmitted to an output shaft.

  When the hole portion having the above-described shape is formed by, for example, cutting, processing is difficult, and thus processing cost may increase. Therefore, in the invention described in claim 5, the hole is formed by press working. According to the press working, the hole having the above-described shape can be easily formed. Therefore, an increase in processing cost can be suppressed.

Sectional drawing which shows the rotary actuator by one Embodiment of this invention. Schematic which shows the shift-by-wire system to which the rotary actuator by one Embodiment of this invention is applied. The figure which looked at the ring gear of the rotary actuator by one Embodiment of this invention, the sun gear, and the output shaft from the arrow III direction of FIG. The partial enlarged view which shows a part of ring gear of the rotary actuator by one Embodiment of this invention, a sun gear, and an output shaft.

Hereinafter, a rotary actuator according to an embodiment of the present invention will be described with reference to the drawings.
(One embodiment)
A rotary actuator 1 shown in FIG. 1 is applied as a drive unit of a shift-by-wire system that switches a shift range of an automatic transmission by electronic control, for example.

  First, the shift-by-wire system will be described. As shown in FIG. 2, the shift-by-wire system 100 drives the manual valve 101 of the automatic transmission by the rotary actuator 1. The shift-by-wire system 100 includes an ECU 2. The ECU 2 outputs a drive signal to the rotary actuator 1. As a result, the rotary actuator 1 rotates according to the drive signal input from the ECU 2. The rotational motion of the rotary actuator 1 is transmitted to the detent mechanism 102. The detent mechanism 102 transmits the rotational driving force output from the rotary actuator 1 to the manual valve 101.

  The detent mechanism 102 includes a manual shaft 103, a detent plate 104, a stopper 105, and the like. The manual shaft 103 is connected to the rotary actuator 1 and is rotated by the rotary actuator 1. The detent plate 104 extends radially outward from the manual shaft 103 and is provided so as to be rotatable integrally with the manual shaft 103. Thereby, the detent plate 104 is rotationally driven by the rotary actuator 1 integrally with the manual shaft 103. The detent plate 104 is provided with a pin 106 that protrudes in parallel with the manual shaft 103. The pin 106 is connected to the manual valve 101. As a result, when the detent plate 104 rotates together with the manual shaft 103, the manual valve 101 reciprocates in the axial direction. That is, the detent mechanism 102 converts the rotational driving force of the rotary actuator 1 into a linear motion and transmits it to the manual valve 101.

  The detent plate 104 has a plurality of recesses 107 on the side opposite to the manual shaft 103 in the radial direction. The concave portions 107 correspond to “P range”, “R range”, “N range”, and “D range”, which are shift ranges of an automatic transmission (not shown), respectively. The stopper 105 is supported at the tip of the leaf spring 108. When the stopper 105 is engaged with any one of the recesses 107 of the detent plate 104, the position of the manual valve 101 in the axial direction is determined. When a rotational force is applied to the detent plate 104 via the manual shaft 103, the stopper 105 moves to another adjacent recess 107. As a result, when the manual shaft 103 is rotated by the rotary actuator 1, the position of the manual valve 101 in the axial direction is changed, and the shift range of the automatic transmission is changed. Note that a range where the “driven torque of the manual shaft 103” is smaller than the “spring force of the leaf spring 108” when the stopper 105 moves to another adjacent recess 107 is referred to as a suction range.

Next, the rotary actuator 1 will be described.
As shown in FIG. 1, the rotary actuator 1 includes a housing 10, an input shaft 20, a switched reluctance (SR) motor 3, a ring gear 50, a sun gear 60, an output shaft 70, and the like. The housing 10 includes a rear housing 11 and a front housing 12. The rear housing 11 and the front housing 12 are made of, for example, resin. The front housing 12 is fixed to the rear housing 11 by bolts 13. The front housing 12 abuts on the rear housing 11 and forms a space 14 between the rear housing 11. An elastic elastic member 15 having elasticity is sandwiched between the front housing 12 and the rear housing 11 in contact with each other.

  The input shaft 20 has a large-diameter portion 21 having an outer diameter larger than that of other portions in the axial direction. The input shaft 20 has a cylindrical eccentric portion 22 that is adjacent to the axial direction side of the large-diameter portion 21 and is eccentric with respect to the rotation center of the input shaft 20. The input shaft 20 is rotatably supported at one end by a front bearing 91 and at the other end by a rear bearing 92. The front bearing 91 is provided on the inner periphery of the output shaft 70 described later. The output shaft 70 is rotatably supported by a metal bearing 93 provided on the inner periphery of the front housing 12. That is, one end portion of the input shaft 20 is rotatably supported via the metal bearing 93, the output shaft 70, and the front bearing 91 provided in the front housing 12. On the other hand, the other end of the input shaft 20 is rotatably supported via a rear bearing 92 provided in the rear housing 11. Thus, the input shaft 20 is rotatably supported by the housing 10.

  The SR motor 3 as an electric motor is a brushless motor that generates a driving force without using a permanent magnet. The SR motor 3 is provided on the rear housing 11 side of the space 14. That is, the SR motor 3 is accommodated in the housing 10. The SR motor 3 has a stator 30 and a rotor 40. The stator 30 is formed in a substantially annular shape, and is fixed to the rear housing 11 in a non-rotatable manner by being press-fitted into a metal plate 16 insert-molded in the rear housing 11.

  The stator 30 includes a stator core 31 and a coil 32. The stator core 31 is formed by laminating a plurality of thin plates in the plate thickness direction. The stator core 31 is provided with a plurality of stator teeth 33 projecting at a predetermined angle toward the inside in the radial direction, and a coil 32 is wound around each of the stator teeth 33.

  The coil 32 is electrically connected to the bus bar portion 80. The bus bar portion 80 is provided on the rear housing 11 side of the stator 30 as shown in FIG. The bus bar portion 80 is formed of, for example, a metal thin plate, and power supplied to the coil 32 flows. The bus bar portion 80 has a terminal 81 connected to the coil 32 on the radially inner side of the coil 32 provided in the stator 30. The coil 32 is electrically connected to the terminal 81 by, for example, welding. Electric power is supplied to the terminal 81 based on the drive signal output from the ECU 2.

  The rotor 40 is provided on the inner peripheral side of the stator 30. The rotor 40 is formed by laminating a plurality of thin plates in the plate thickness direction. The rotor 40 includes a rotor core 41 and salient poles 42. The rotor core 41 is formed in a substantially annular shape, and is press-fitted and fixed to the large-diameter portion 21 of the input shaft 20. A plurality of salient poles 42 are provided at predetermined angles so as to project from the rotor core 41 toward the outer stator 30. The rotor 40 is rotatable relative to the housing 10 and the stator 30 by press-fitting and fixing the rotor core 41 to the input shaft 20.

  When electric power is supplied to the coil 32, a magnetic force is generated in the stator teeth 33 around which the coil 32 is wound. As a result, the salient poles 42 of the corresponding rotor 40 are attracted to the stator teeth 33. The plurality of coils 32 constitute, for example, three phases of U phase, V phase, and W phase. When the ECU 2 switches energization in the order of the U phase, V phase, and W phase, the rotor 40 rotates, for example, counterclockwise, and conversely when the energization is switched in the order of the W phase, V phase, and U phase, the rotor 40 rotates. Rotate around. Thus, by switching the energization to each coil 32 and controlling the magnetic force generated in the stator teeth 33, the rotor 40 can be rotated in an arbitrary direction.

  As shown in FIG. 3, the ring gear 50 is formed in a substantially annular shape. The ring gear 50 has internal teeth 51 formed at the inner edge. The ring gear 50 is made of, for example, metal, and is fixed to the housing 10 so as not to rotate by being press-fitted into an annular plate 17 insert-molded in the front housing 12 (see FIG. 1). Here, the ring gear 50 is fixed to the housing 10 so as to be coaxial with the input shaft 20.

  The sun gear 60 is formed, for example, in a substantially disk shape from metal. As shown in FIGS. 1 and 3, the sun gear 50 has a columnar protrusion 61 formed so as to protrude in the plate thickness direction from a position radially away from the center of one surface in a radial direction. Yes. In the present embodiment, nine protrusions 61 are provided at predetermined intervals in the circumferential direction of the sun gear 60. The sun gear 60 has external teeth 62 formed on the outer edge so as to mesh with the internal teeth 51 of the ring gear 50. The sun gear 60 is provided so as to be eccentric relative to the input shaft 20 via a middle bearing 94 provided on the outer periphery of the eccentric portion 22 of the input shaft 20. Accordingly, when the input shaft 20 rotates, the sun gear 60 rotates and revolves inside the ring gear 50 while the outer teeth 62 mesh with the inner teeth 51 of the ring gear 50.

  The output shaft 70 is made of, for example, metal. As shown in FIGS. 1 and 3, the output shaft 70 includes a substantially cylindrical tube portion 71 and a substantially disk-shaped disc portion 72. The cylindrical portion 71 is rotatably supported by the housing 10 via a metal bearing 93 provided on the front housing 12. Here, the cylindrical portion 71 is provided so as to be coaxial with the input shaft 20. A front bearing 91 is provided inside the cylindrical portion 71. Thereby, the cylinder part 71 is supporting the one edge part of the input shaft 20 through the metal bearing 93 and the front bearing 91 rotatably. A spline groove 74 is formed on the inner side of the cylindrical portion 71.

  The disk part 72 is formed in a substantially disk shape so as to expand radially outward from one end of the cylinder part 71. The disk portion 72 is formed with a hole 73 into which the protruding portion 61 of the sun gear 60 can enter. The hole 73 is formed by pressing so as to penetrate the disk portion 72 in the plate thickness direction. In the present embodiment, nine holes 73 correspond to the protrusions 61 and are formed in the circumferential direction of the disk part 72.

  With the above-described configuration, when the sun gear 60 rotates and revolves inside the ring gear 50, the inner wall of the disk portion 72 in which the hole 73 is formed is pushed against the outer wall of the protruding portion 61. Thereby, the rotation component of the sun gear 60 is transmitted to the output shaft 70. The rotation speed of the sun gear 60 is slower than the rotation speed of the input shaft 20. Therefore, the rotational output of the SR motor 3 is decelerated and output from the output shaft 70. That is, the ring gear 50, the sun gear 60, and the output shaft 70 constitute a reduction gear. Note that the output shaft 70 and the manual shaft 103 are spline-coupled by fitting one end of the manual shaft 103 of the shift-by-wire system 100 described above into the spline groove 74 of the output shaft 70.

Hereinafter, the shape and the like of the hole 73 formed in the disk portion 72 will be described with reference to FIG.
As shown in FIG. 4, when viewed from the axial direction of the output shaft 70, the hole portion 73 has an outer shape “a virtual circle 110 having a diameter larger than the outer diameter of the protruding portion 61 is located in the circumferential direction of the disk portion 72. It is formed in a circular shape that is long in a predetermined direction so as to coincide with the “outer edge of the locus when quantitatively moving”. That is, when the virtual circle 110 moves to the position of the virtual circle 120 shown in FIG. 4 in the circumferential direction of the disk portion 72, the shape of the outer edge of the locus is a circle that is long in the predetermined direction. Is formed to match the shape of the outer edge. Here, the “predetermined direction” coincides with the circumferential direction of the disk portion 72.

Next, a graphic 730 that matches the outer shape of the hole 73 will be described.
In the present embodiment, the graphic 730 coincides with the outer edge. Among the lines constituting the graphic 730, “a straight line L1 connecting the axis O of the output shaft 70 and the center C1 of the virtual circle 110” and “a straight line L2 connecting the axis O of the output shaft 70 and the center C2 of the virtual circle 120”. One (line 731) of the part cut out by and coincides with the arc of the virtual circle 130 centered on the axis O. Further, among the lines constituting the graphic 730, the other part (line 732) of the cut portion coincides with the arc of the virtual circle 140 centered on the axis O. In addition, among the lines constituting the graphic 730, the straight line L 1 side (line 733) between the lines 731 and 732 coincides with the arc of the virtual circle 110. Furthermore, the straight line L 2 side (line 734) of the part sandwiched between the line 731 and the line 732 among the lines constituting the graphic 730 coincides with the arc of the virtual circle 120.

  In the present embodiment, since the hole 73 is formed as described above, between the outer wall of the protruding portion 61 and the inner wall of the disk portion 72 where the hole 73 is formed, as shown in FIG. A play (gap S) of a predetermined size is formed. With this backlash, in this embodiment, the suction range of the detent mechanism 102 driven by the rotary actuator 1 can be widened. Accordingly, rough rotation control can be performed when the driven object is driven by the rotary actuator 1.

Further, according to the above-described configuration, the radial width of the disk portion 72 of the outer shape of the hole portion 73 is smaller than the circumferential width of the disk portion 72. Thereby, the outer diameter of the disk part 72 in which the hole part 73 is formed can be made small. Therefore, the physique of the output shaft 70 can be reduced, and as a result, the physique of the rotary actuator 1 can be reduced.
As described above, in the rotary actuator 1 according to the present embodiment, the driving target can be driven by rough rotation control, but the physique is not increased.

  In the present embodiment, a plurality of hole portions 73 are formed in the circumferential direction of the disk portion 72. A plurality of protrusions 61 are formed in the circumferential direction of the sun gear 60 so as to correspond to the holes 73. Thereby, the rotation component of the sun gear 60 can be smoothly and efficiently transmitted to the output shaft 70.

  Further, in the present embodiment, the hole 73 is formed by press working. According to the press working, the hole 73 having the above-described shape can be easily formed as compared with, for example, cutting. Therefore, an increase in processing cost can be suppressed.

(Other embodiments)
In another embodiment of the present invention, when viewed from the axial direction of the sun gear, the outer shape of the hole is “when a virtual circle having a diameter larger than the outer diameter of the protruding portion moves a predetermined amount in the circumferential direction of the sun gear. It may not exactly coincide with the “outer edge of the locus”. That is, for example, the hole portion may be formed so that the line 732 constituting the graphic 730 described in the above embodiment is not an arc but a straight line. Even with such a configuration, the above-described effects can be fully enjoyed.

  In the above-described embodiment, the example in which the protruding portion 61 is formed in the sun gear 60 and the hole portion 73 is formed in the disk portion 72 of the output shaft 70 has been described. On the other hand, in another embodiment of the present invention, a hole may be formed in the sun gear 60 and a protrusion may be formed in the disk portion 72. If the hole and the protrusion are formed in the same shape as the hole 73 and the protrusion 61 of the above-described embodiment, the same effect as that of the above-described embodiment can be obtained.

  In another embodiment of the present invention, only one hole and one protrusion may be formed. Even in such a configuration, the rotation component of the sun gear can be transmitted to the output shaft within the predetermined rotation angle range, and the above-described effects can be obtained.

Moreover, in other embodiment of this invention, the hole part may be formed by cutting.
In another embodiment of the present invention, a motor other than the SR motor may be employed as the electric motor.
Furthermore, in another embodiment of the present invention, the rotary actuator is not limited to a shift-by-wire system and can be applied to various functional parts.
As described above, the present invention is not limited to the above-described embodiment, and can be applied to various embodiments without departing from the gist thereof.

  1: rotary actuator, 3: SR motor (electric motor), 10: housing, 20: input shaft, 50: ring gear, 51: internal gear, 60: sun gear, 61: protrusion, 62: external gear, 70: output Shaft, 72: Disk part, 73: Hole part

Claims (5)

A housing;
An input shaft rotatably supported by the housing;
An electric motor housed in the housing and rotationally driving the input shaft;
A ring gear formed in an annular shape, having internal teeth formed at an inner edge, and fixed to the housing so as to be coaxial with the input shaft;
Formed in a disk shape, a cylindrical protrusion formed to protrude in the plate thickness direction from a position radially away from the center of one surface, and formed on the outer edge to engage with the inner teeth The outer teeth are rotated and revolved inside the ring gear while the outer teeth mesh with the inner teeth as the input shaft rotates. With sun gear,
It has a disk part in which a hole part into which the projection part can enter is formed, is rotatably supported by the housing so as to be coaxial with the input shaft, and an inner wall of the disk part in which the hole part is formed is An output shaft to which the rotation component of the sun gear is transmitted by being pushed by the outer wall of the protrusion,
When the hole portion is viewed from the axial direction of the output shaft, the outer shape is “the outer edge of the locus when a virtual circle having a diameter larger than the outer diameter of the protruding portion moves a predetermined amount in the circumferential direction of the disk portion. A rotary actuator characterized by being formed in a circular shape that is long in a predetermined direction so as to substantially coincide with the “end”. A plurality of the hole portions are formed in the circumferential direction of the disk portion,
2. The rotary actuator according to claim 1, wherein a plurality of the protrusions are formed in the circumferential direction of the sun gear in correspondence with the holes. A housing;
An input shaft rotatably supported by the housing;
An electric motor housed in the housing and rotationally driving the input shaft;
A ring gear formed in an annular shape, having internal teeth formed at an inner edge, and fixed to the housing so as to be coaxial with the input shaft;
A hole formed in a disk shape at a predetermined distance from the center in a radial direction, and an outer tooth formed on an outer edge portion to mesh with the inner tooth, and relative to the input shaft A sun gear which is provided eccentrically so as to be rotatable, and rotates and revolves inside the ring gear while the outer teeth mesh with the inner teeth by rotating the input shaft;
It has a disk part formed with a cylindrical protrusion protruding from the surface on the sun gear side in the plate thickness direction so as to be able to enter the hole part, and is rotatably supported by the housing so as to be coaxial with the input shaft. And an output shaft to which the rotation component of the sun gear is transmitted by pressing the outer wall of the projecting portion by the inner wall of the sun gear in which the hole is formed,
When the hole is viewed from the axial direction of the sun gear, the outer shape is "the outer edge of the locus when a virtual circle having a diameter larger than the outer diameter of the protrusion moves a predetermined amount in the circumferential direction of the sun gear" A rotary actuator characterized in that it is formed in a circular shape that is long in a predetermined direction so as to substantially match. A plurality of the holes are formed in the circumferential direction of the sun gear,
4. The rotary actuator according to claim 3, wherein a plurality of the protruding portions are formed in the circumferential direction of the disk portion so as to correspond to the hole portions. 5.   The rotary actuator according to claim 1, wherein the hole portion is formed by press working.

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