Reclining device

Abstract

To provide a reclining device which enables movement in an eccentric direction between an internal tooth gear and an external tooth gear to the extent that the external tooth gear and the internal tooth gear are surely engaged at the time of lock, and can stabilize slide by bringing the member into contact with a cylindrical boss of a gear with a large area even at the time of slide.SOLUTION: A reclining device 100 includes: an external tooth gear 10; an internal tooth gear 20; a ring 40 which is formed so that a center of an outer peripheral surface formed in a circle and a center of an inner peripheral surface formed in a circle are eccentric, and is formed with a through hole for an elastic body; a rotary shaft 30 having a pressing extension part for pressing the ring 40; a pair of wedge-shaped cams 50 arranged on a back face side of the ring 40; and an elastic body 60 for energizing the pair of wedge-shaped cams 50 through the through hole for the elastic body of the ring 40 so as to separate the pair of wedge-shaped cams 50.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a reclining device.

Background Art

[0002] Various reclining devices for a seat that hold a seat back so as to be tiltable with respect to a seat cushion have been proposed (for example, Patent Document 1, etc.). In such a reclining device, as shown in FIG. 9, an external gear 310 having a through hole 312 coaxial with the axial direction on the inner peripheral surface, an internal gear formed on the outer peripheral surface that can mesh with external teeth, and a cylindrical boss 322 coaxial with the axial direction on the inner peripheral surface. An internal gear 320, a rotating shaft 330 that fits coaxially and rotatably with the external gear 310 and rotates one of the external gear 310 and the internal gear 320 around the other gear shaft, a bush 340 provided between the through hole 312 and the cylindrical boss 322, and a pair of wedge-shaped cams 350 provided on the bush 340 that simultaneously contact the cylindrical boss 322 side and the bush 340 to restrict the rotation of the cylindrical boss 322 and the bush 340, and at least one of the cylindrical boss 322 and the bush 340 is slid, and the rotation of the cylindrical boss 322 and the bush 340 is allowed.

[0003] In the reclining device 300 having such a configuration, when the external gear 310 and the internal gear 320 are meshed in an eccentric state, the contact point (μ) between the bush 340 on the side opposite to the meshing side and the through hole 312 of the external gear 310 needs to move slightly up and down relatively in order for the external gear 310 to rotate with respect to the internal gear 320, so a gap is required. Also, even in the locked state, a gap is required to efficiently and reliably mesh the external gear 310 and the internal gear 320 to prevent rattling. However, during sliding, since contact is made over the entire circumference of the bush, force can be efficiently transmitted and it can serve as a bearing, so the sliding is stabilized and smooth rotation can be ensured. Therefore, it is preferable not to provide a gap at such a contact point (μ).

[0004] Thus, from the viewpoints of the necessity of rotation and prevention of rattling, the generation of a gap is necessary. However, there is a problem in that a technically contradictory phenomenon occurs in that it is not desirable to leave a gap for stabilization during sliding.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] Therefore, the present invention has been made in view of such problems, and at the time of locking, the inner gear and the outer gear can move in the eccentric direction to such an extent that the meshing side of the outer gear and the inner gear meshes surely, and also at the time of sliding, the member is in contact with the cylindrical boss of the gear over a large area, so that it is possible to provide a reclining device capable of stabilizing the sliding.

Means for Solving the Problems

[0007] In order to achieve the above object, the present invention has adopted the following means.

[0008] The reclining device of the present invention is a reclining device for a seat that tiltably holds a seat back frame constituting a seat back with respect to a seat cushion frame constituting a seat cushion, an external gear that is directly or indirectly attached to one of the seat cushion frame and the seat back frame, has external teeth formed on an outer peripheral surface thereof, and has a through hole coaxial with an axial direction formed on an inner peripheral surface thereof; and An internal gear having internal teeth that are directly or indirectly attached to the other of the seat cushion frame and the seat back frame, having internal teeth that can mesh with the external teeth provided on the inner peripheral surface with at least one or more more than the external teeth, and having a cylindrical boss coaxial with the axial direction; A ring disposed between the inner periphery of the through hole of the external gear and the outer periphery of the cylindrical boss of the internal gear, the center of the circular outer peripheral surface and the center of the circular inner peripheral surface being eccentrically formed, and having an engaging convex portion or an engaging concave portion on the front side; A pair of wedge-shaped cams disposed on the front side of the ring, which regulate the relative rotation of the external gear and the internal gear by contacting the outer peripheral surface of the cylindrical boss of the internal gear and the inner peripheral surface of the through hole of the external gear, and slide the outer peripheral surface of the cylindrical boss of the internal gear and the inner peripheral surface of the through hole of the external gear to allow relative rotation of the external gear and the internal gear; A rotating shaft coaxially and rotatably inserted into the cylindrical boss of the internal gear, having a pressing extension portion that engages with the engaging convex portion or the engaging concave portion of the ring to rotate the ring and press the wedge-shaped cam; An elastic body that biases the pair of wedge-shaped cams in a direction away from each other, characterized by comprising.

[0009] In the present invention, a wedge-shaped cam is disposed on the front side of the ring, and by making it a two-stage stack, the functions of the ring that ensures contact with the cylindrical boss and the wedge-shaped cam that moves the external gear in the direction of meshing with the internal gear are separated, so that the ring is brought into contact with the entire circumference of the cylindrical boss serving as a bearing, and the external gear can be effectively meshed with the internal gear by moving it to the internal gear. For this reason, during sliding, the sliding is stabilized, smooth rotation can be ensured, and the occurrence of rattling in the locked state can be prevented.

[0010] Further, in the reclining device according to the present invention, a substantially U-shaped bush is provided on the outer peripheral side of the wedge-shaped cam, and the wedge-shaped cam regulates the relative rotation of the external gear and the internal gear by bringing the outer peripheral surface of the cylindrical boss of the internal gear and the inner peripheral surface of the bush into contact with each other, and slides the inner peripheral surface of the cylindrical boss of the bush and the internal gear or the inner peripheral surface of the through hole of the bush and the external gear to allow the relative rotation of the external gear and the internal gear. It may be characterized by this.

[0011] By adopting such a configuration, while ensuring a two-stage stacked configuration that secures contact with the cylindrical boss by the ring and ensures meshing between the internal gear and the external gear by the wedge-shaped cam, it is possible to reduce the time lag with respect to the movement of the wedge-shaped cam and enable quick operation.

[0012] Further, in the reclining device according to the present invention, it is a reclining device for a seat that tiltably holds a seat back frame constituting a seat back with respect to a seat cushion frame constituting a seat cushion, An external gear directly or indirectly attached to one of the seat cushion frame and the seat back frame, having external teeth formed on the outer peripheral surface and a cylindrical boss coaxial with the axial direction formed on the inner peripheral surface, and An internal gear directly or indirectly attached to the other of the seat cushion frame and the seat back frame, having internal teeth meshing with the external teeth provided at least one or more more than the external teeth, and having a through hole coaxial with the axial direction formed, and A ring disposed between the inner periphery of the through hole of the internal gear and the outer periphery of the cylindrical boss of the external gear, having the center of the circularly formed outer peripheral surface and the center of the circularly formed inner peripheral surface eccentrically formed, and having an engaging convex portion or an engaging concave portion on the front side, and Disposed on the front side of the ring, by contacting the outer peripheral surface of the cylindrical boss of the external gear and the inner peripheral surface of the through hole of the internal gear, it restricts the relative rotation between the external gear and the internal gear, and slides the outer peripheral surface of the cylindrical boss of the external gear and the inner peripheral surface of the through hole of the internal gear to allow the relative rotation between the external gear and the internal gear. A pair of wedge-shaped cams, A rotary shaft that is coaxially and rotatably inserted into the cylindrical boss of the external gear, engages with the engaging convex portion or the engaging concave portion of the ring to rotate the ring, and has a pressing extension portion that presses the wedge-shaped cam. It is characterized by comprising an elastic body that biases the pair of wedge-shaped cams in a direction away from each other.

[0013] In the present invention, compared with the above-described invention, the external gear is provided with a cylindrical boss and the internal gear is formed with a through hole, but similarly, by adopting a two-stage stacked configuration in which wedge-shaped cams are arranged on the front surface of the ring, a ring that ensures contact with the cylindrical boss and a wedge-shaped cam that moves the external gear in the direction of meshing with the internal gear are separated in function, thereby preventing the occurrence of rattling in the locked state and ensuring stable sliding and smooth rotation during sliding.

[0014] Also, in the reclining device according to the present invention, A substantially U-shaped bush is provided on the outer peripheral side of the wedge-shaped cam. The wedge-shaped cam restricts the relative rotation between the external gear and the internal gear by contacting the outer peripheral surface of the cylindrical boss of the external gear and the inner peripheral surface of the bush, and slides the bush and the outer peripheral surface of the cylindrical boss of the external gear or the inner peripheral surface of the through hole of the internal gear of the bush to allow the relative rotation between the external gear and the internal gear. It may be characterized in that.

[0015] With such a configuration, while ensuring a two-stage stacked configuration that secures contact with the cylindrical boss by the ring and ensures meshing between the internal gear and the external gear by the wedge-shaped cam, it is possible to reduce the time lag with respect to the movement of the wedge-shaped cam and enable quick operation.

Brief Description of Drawings

[0016]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Embodiments for Carrying Out the Invention

[0017] Hereinafter, the reclining device 100 according to an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic diagram of a vehicle seat 200, FIG. 2 is a front view showing the internal structure of the reclining device 100, FIG. 3 is an exploded perspective view of the reclining device 100, and FIG. 4 is a front view of a ring 40. It should be noted that the embodiments and drawings described below are examples of a part of the embodiments of the present invention and are not used for the purpose of limiting to these configurations. In each figure, the corresponding components are given the same or similar reference numerals. Also, in FIG. 3, as indicated by the arrows in the figure, one direction of the external gear 10 is referred to as "front", and one direction of the internal gear 20 is referred to as "rear".

[0018] (First Embodiment) As shown in FIG. 1, the reclining device 100 according to the first embodiment is attached to the center position of the tilt of the seat back 220 that is tiltably attached to the seat cushion 210 of the vehicle seat 200, and is a device that gives the seat back 220 a tilting function. Specifically, it is directly or indirectly attached and used via another mounting plate 230 (hereinafter referred to as "mounting plate etc.") between the seat cushion frame disposed inside the seat cushion 210 and the seat back frame disposed inside the seat back 220.

[0019] As mainly shown in FIGS. 2 and 3, the reclining device 100 according to the present invention includes an external gear 10, an internal gear 20, a rotating shaft 30, a ring 40, a wedge-shaped cam 50, a spring 60 as an elastic body, a spring cover 70, and a plate cover 80. In FIG. 2, the spring 60, the spring cover 70, and the plate cover 80 are omitted for easy viewing of the internal structure.

[0020] As shown in FIG. 3, the external gear 10 is formed in a disc shape, external teeth 11 are formed on the outer peripheral surface, and a cylindrical through-hole 12 is formed at the center. A protrusion 13 is provided on the front surface 10b of the external gear 10, and it is attached to the vehicle seat by welding or the like in a state of being fitted into a fitting hole provided in a mounting plate or the like 230.

[0021] The internal gear 20 is formed in a disc shape having a diameter larger than that of the external gear 10. A cylindrical recess is formed so that the external gear 10 can be mounted inside, and internal teeth 21 are formed on the inner peripheral surface of this recess. The internal teeth 21 are formed with at least one or more teeth more than the number of teeth of the external teeth 11 of the external gear 10. As shown in FIG. 2, the external gear 10 and the internal gear 20 mesh with the internal teeth 21 and the external teeth 11 such that the centers C1 of the external gear 10 and C2 of the internal gear 20 are eccentric. Therefore, the external gear 10 and the internal gear 20 form a differential gear. When the internal gear 20 makes one revolution around the external teeth 11, the rotation advances by the difference in the number of teeth between the internal teeth 21 and the external teeth 11. That is, for example, when there is a difference of only one tooth, when the external gear 10 makes one revolution around the internal gear 20, it rotates by one tooth. As shown in FIG. 3, a cylindrical boss 22 is provided at the center of the internal gear 20. A protrusion 23 is provided on the back surface of the internal gear 20, and it is attached to the vehicle seat by welding or the like in a state of being fitted into a fitting hole provided in a mounting plate or the like 230.

[0022] The ring 40 is an annular member disposed between the inner peripheral surface of the through-hole 12 of the external gear 10 and the outer peripheral surface 22a of the cylindrical boss 22 of the internal gear 20. As shown in FIG. 4, the center of the circularly formed outer peripheral surface 43 and the center of the circularly formed inner peripheral surface 44 are eccentrically formed so as to be equal to the amount of eccentricity between the center of the external gear 10 and the center of the internal gear 20. As shown in FIG. 2, an engaging convex portion 41 is provided on the front side so as to have a gap between the separated side ends 54 of the pair of wedge-shaped cams 50, which will be described later. The ring 40 is preferably formed so as to be in contact with the cylindrical boss 22 of the internal gear 20 with as little gap as possible, and is preferably arranged with respect to the through-hole 12 of the external gear 10 so that a gap is provided in the eccentric direction between the centers of the external gear 10 and the internal gear 20 so that the external gear 10 can move. By manufacturing in this way, since the entire circumference of the outer peripheral surface is in contact with the cylindrical boss 22, during sliding, the sliding is stabilized and smooth rotation can be ensured. On the other hand, since the external gear 10 can be moved in the eccentric direction by the wedge-shaped cam 50, which will be described later, the occurrence of rattling in the locked state can be prevented.

[0023] As shown in FIG. 3, the wedge-shaped cam 50a and the wedge-shaped cam 50b are formed symmetrically with respect to a plane. The concave surface 51 (the inner surface) of the wedge-shaped cam 50 has the same curved surface as the curved surface of the outer peripheral surface 22a of the cylindrical boss 22, and the convex surface 52 (the outer surface) is formed so as to gradually become thinner from the side where the wall thickness faces each other. The wedge-shaped cam 50a and the wedge-shaped cam 50b are arranged such that the proximal ends 53, which are the thick sides of the wall thickness, face each other, and as shown in FIG. 5, between the inner peripheral surface 12a of the through-hole 12 of the external gear 10 and the outer peripheral surface 22a of the cylindrical boss 22 of the internal gear 20, they are disposed on the front side of the ring 40 described above so as to be in contact with each other, that is, on the side of the rotating shaft 30. By arranging the ring 40 and the wedge-shaped cam 50 in a two-stage stack in this way, the ring 40 can ensure contact with the outer peripheral surface 22a of the cylindrical boss 22, and the wedge-shaped cam 50 can separate the function of maintaining the eccentric state between the external gear 10 and the internal gear 20.

[0024] The rotating shaft 30 is coaxially and rotatably inserted into the cylindrical boss 22 of the internal gear 20. Further, the rotating shaft 30 is rotationally driven when adjusting the tilt of the seat back 220, and serrations 31 are provided on the inner cylindrical surface to receive the rotational force of the tilting motor. Furthermore, the rotating shaft 30 is arranged in the vicinity of or in contact with the separation-side end portions 54 of the pair of wedge-shaped cams 50a and 50b, and has a pressing extension portion 32 extended in the vicinity of or in contact with the engaging convex portion 41 of the ring 40. That is, the pressing extension portions 32 are formed at two locations, namely, between the wedge-shaped cam 50a and the engaging convex portion 41 and between the wedge-shaped cam 50b and the engaging convex portion 41. Thereby, by rotating the rotating shaft 30, the wedge-shaped cams 50 and the ring 40 can be pressed and rotated.

[0025] The spring 60 is made of an elastic body and, as shown in FIG. 3, has an annular portion 61 and end portions 62a and 62b that rise up from the annular portion 61 at an angle of 90°. The end portions 62a and 62b are respectively in contact with the proximity-side end portions 53 of the wedge-shaped cams 50, and bias the pair of wedge-shaped cams 50a and 50b in the separating direction.

[0026] The reclining device 100 thus manufactured operates as follows. When no force is applied to the rotating shaft 30 and it is not rotating, the pair of wedge-shaped cams 50a and 50b are biased by the spring 60 in the separating direction and are in contact with the inner peripheral surface 12a of the through-hole 12 of the external gear 10 and the outer peripheral surface 22a of the cylindrical boss 22 of the internal gear 20. Therefore, the relative movement between the internal gear 20 and the external gear 10 is locked, and the seat back 220 is in a locked state.

[0027] From this locked state, when the rotating shaft 30 is rotated counterclockwise in FIG. 2, for example, the wedge-shaped cam 50b is pressed by the pressing extension portion 32 of the rotating shaft 30. A wedge angle is set between the wedge-shaped cam 50b and the inner peripheral surface 12a of the through hole 12 of the external gear 10. Due to the pressing of the wedge-shaped cam 50b, a gap is generated between the inner peripheral surface of the wedge angle and the wedge-shaped cam 50b, and the wedge comes off. As a result, a gap is generated between the wedge-shaped cam 50 and the cylindrical boss 22 and between the wedge-shaped cam 50 and the through hole 12 of the external gear 10, and the external gear 10 becomes rotatable with respect to the internal gear 20. Further, the ring 40 rotates counterclockwise with respect to the internal gear 20, and accordingly, the wedge-shaped cam 50a rotates counterclockwise so as to fill this gap by the biasing force of the spring 60. The wedge-shaped cam 50 rotates counterclockwise so as to slide together with the rotating shaft 30 and the ring 40. Thus, the external gear 10, the internal gear 20, and the rotating shaft 30 constitute a differential gear mechanism. Note that clockwise rotation can be performed in the same manner. At this time, since the engaging convex portion 41 of the ring 40 is also pressed by the pressing extension portion 32 and rotates in the same manner, the ring 40 rotates so as to follow the eccentric direction between the internal gear 20 and the external gear 10, and during rotation, the ring 40 comes into contact with most of the outer peripheral surface 22a of the cylindrical boss 22. In the case of sliding, the sliding is stabilized and smooth rotation can be ensured. On the other hand, since the external gear 10 is biased by the wedge-shaped cam 50 to move in the eccentric direction with respect to the internal gear 20, it is possible to prevent the occurrence of rattling in the locked state.

[0028] In the first embodiment, when the ring 40 is rotated by the rotating shaft 30, the engaging convex portion 41 of the ring 40 is pressed and rotated by the pressing extension portion 32 of the rotating shaft 30. However, the present invention is not limited to this, and as long as the ring 40 can rotate along with the rotation of the rotating shaft 30, the configuration is not particularly limited. For example, as shown in FIG. 6, an engaging concave portion 42 into which the pressing extension portion 32 of the rotating shaft 30 can be inserted may be formed in the ring 40 so that it can rotate according to the rotation of the rotating shaft 30.

[0029] (Second Embodiment) An exploded perspective view of the reclining device 100 according to the second embodiment is shown in FIG. 7. The reclining device 100 according to the second embodiment is the same as that of the first embodiment except that a bush 90 is added and the shape and arrangement of the wedge-shaped cam 50 are different, and thus the description thereof is omitted.

[0030] The reclining device 100 according to the second embodiment is different in that a substantially U-shaped bush 90 is provided on the convex surface 52 (outer surface) side of the wedge-shaped cam 50. The substantially U-shaped bush 90 is formed in a substantially U shape as shown in FIG. 7. The wedge-shaped cam 50 is formed smaller than that of the first embodiment so as to fit within the inner circumference of the bush 90. The wedge-shaped cam 50 regulates the relative rotation of the external gear 10 and the internal gear 20 by bringing the outer peripheral surface 22a of the cylindrical boss 22 of the internal gear 20 into contact with the inner peripheral surface of the bush 90, and allows the relative rotation of the external gear 10 and the internal gear 20 by sliding the inner peripheral surface of the cylindrical boss 22 of the bush 90 and the internal gear 20 or the inner peripheral surface of the through hole 12 of the bush 90 and the external gear 10.

[0031] In the reclining device 100 manufactured as described above, when no force is applied to the rotary shaft 30 and it is not rotated, the pair of wedge-shaped cams 50a and 50b are biased by the spring 60 in a direction in which they are separated from each other and are in contact with the inner peripheral surface of the bush 90 and the outer peripheral surface 22a of the cylindrical boss 22 of the internal gear 20. Therefore, the relative movement between the internal gear 20 and the external gear 10 is locked, and the seat back 220 is in a locked state.

[0032] From this locked state, if the rotating shaft 30 is rotated counterclockwise, for example, the bush 90 is pressed by the pressing extension part 32 of the rotating shaft 30 and rotates accordingly. Also, a wedge angle is set between the inner wall surface of the bush 90, and the inner wall of the wedge angle is in contact with the wedge-shaped cam 50. Due to the rotation of the bush 90, a gap is generated between the inner wall of the wedge angle and the wedge-shaped cam 50, and the wedge comes off. The rotating shaft 30 and the bush 90 rotate counterclockwise with respect to the internal gear 20. As a result, a gap is generated between the bush 90 and the cylindrical boss 22 and between the bush 90 and the through hole 12 of the external gear 10, and the external gear 10 becomes rotatable with respect to the internal gear 20. Along with this, the wedge-shaped cam 50a rotates counterclockwise so as to fill this gap by the biasing force of the spring 60. The wedge-shaped cam 50 rotates counterclockwise so as to slide together with the rotating shaft 30 and the bush 90. Note that rotation in the clockwise direction can also be performed in the same manner.

[0033] Since the ring 40 ensures contact with the cylindrical boss 22 and a two-stage structure is ensured to ensure the meshing between the internal gear 20 and the external gear 10 by the wedge-shaped cam 50, while having the same effect as the first embodiment, it is possible to reduce the time lag with respect to the movement of the wedge-shaped cam 50 and enable a quick operation with respect to the rotational operation of the rotating shaft 30.

[0034] (Third Embodiment) The reclining device 100 according to the third embodiment is shown in Fig. 8. The reclining device 100 according to the third embodiment is different from the reclining device 100 according to the first embodiment in that a cylindrical boss 14 is provided at the center of the external gear 10 and a through hole 25 is provided at the center of the internal gear 20. Further, a spring cover 70 for preventing the rotation shaft 30, the ring 40, the wedge-shaped cam 50 and the spring 60 from moving in the axial direction is provided on the back side of the internal gear 20, and a protruding portion 71 that fits into the fitting hole of the mounting plate 230 or the like is provided on the spring cover 70. On the other hand, the plate cover 80 is formed of a metal plate formed in an annular shape, is disposed on the front side of the external gear 10, is fixed to the outer peripheral side end of the internal gear 20 by welding or the like, and restricts the axial movement of the external gear 10.

[0035] The rotation shaft 30, the ring 40, the wedge-shaped cam 50 and the spring 60 are arranged symmetrically with respect to the first embodiment. The ring 40 is arranged between the outer peripheral surface 14a of the cylindrical boss 14 of the external gear 10 and the through hole 25 of the internal gear 20 such that the cylindrical boss 14 is inserted into the inner peripheral surface of the ring 40. The rotation shaft 30 is arranged in the cylindrical boss 14 so as to rotate coaxially with the central axis of the cylindrical boss 14. Similar to the first embodiment, a pressing extension 32 for pressing the wedge-shaped cam 50 is provided, and the wedge-shaped cam 50 can be rotated both clockwise and counterclockwise.

[0036] The reclining device 100 thus manufactured operates as follows. When no force is applied to the rotation shaft 30 and it is not rotating, the pair of wedge-shaped cams 50a and 50b are biased by the spring 60 in a direction in which they are separated, and are in contact with the inner peripheral surface 25a of the through hole 25 of the internal gear 20 and the outer peripheral surface 14a of the cylindrical boss 14 of the external gear 10. Therefore, the relative movement between the internal gear 20 and the external gear 10 is locked, and the seat back 220 is in a locked state.

[0037] From this locked state, when the rotating shaft 30 is rotated, for example, counterclockwise, the wedge-shaped cam 50b is pressed by the pressing extension part 32 of the rotating shaft 30. A wedge angle is set between the wedge-shaped cam 50b and the inner peripheral surface 25a of the through hole 25 of the internal gear 20. Due to the pressing of the wedge-shaped cam 50b, a gap is generated between the inner peripheral surface of the wedge angle and the wedge-shaped cam 50b, and the wedge comes off. As a result, a gap is generated between the wedge-shaped cam 50 and the cylindrical boss 14 and between the wedge-shaped cam 50 and the through hole 25 of the internal gear 20, and the external gear 10 becomes rotatable relative to the internal gear 20. Also, the ring 40 rotates counterclockwise relative to the internal gear 20. Along with this, the wedge-shaped cam 50a rotates counterclockwise so as to fill this gap by the biasing force of the spring 60. The wedge-shaped cam 50 rotates counterclockwise so as to slide together with the rotating shaft 30 and the ring 40. Note that rotation in the clockwise direction can also be performed in the same manner.

[0038] The reclining device 100 thus manufactured is in a state of being in contact with the outer peripheral surface 14a of the cylindrical boss 14 by the ring 40. During sliding, the sliding is stabilized, smooth rotation can be ensured, and since the wedge-shaped cam 50 biases the external gear 10 to move in the eccentric direction with respect to the internal gear 20, the generation of rattling in the locked state can be prevented.

[0039] In addition, in the third embodiment, similar to the second embodiment, a substantially U-shaped bush 90 may be provided on the convex surface 52 (outer surface) side of the wedge-shaped cam 50.

[0040] Note that the present invention is not limited to the above-described embodiments at all, and can be implemented in various modes as long as it belongs to the technical scope of the present invention.

Industrial Applicability

[0041] As shown in the above-described embodiments, it is mainly industrially applicable as a reclining device for vehicle seats.

Explanation of Reference Numerals

[0042] 10... external gear, 10b... front face, 11... external teeth, 12... through hole, 12a... inner peripheral surface, 13... protrusion, 14... cylindrical boss, 14a... outer peripheral surface, 20... internal gear, 21... internal teeth, 22... cylindrical boss, 22a... outer peripheral surface, 23... protrusion, 25... through hole, 25a... inner peripheral surface, 30... rotating shaft, 31... serration, 32... press-rolling portion, 40... ring, 41... engaging convex portion, 42... engaging concave portion, 43... outer peripheral surface, 44... inner peripheral surface, 50... wedge-shaped cam, 50a... wedge-shaped cam, 50b... wedge-shaped cam, 51... concave surface, 52... convex surface, 53... proximal end portion, 54... distal end portion, 60... spring, 61... annular portion, 62a, 62b... end portions, 70... spring cover, 71... protrusion, 80... plate cover, 90... bush, 100... reclining device, 200... vehicle seat, 210... seat cushion, 220... seat back, 230... mounting plate

Claims

1. A reclining device for a seat that tiltably holds a seat back frame constituting a seat back with respect to a seat cushion frame constituting a seat cushion, An external gear that is directly or indirectly attached to one of the seat cushion frame and the seat back frame, has external teeth formed on its outer peripheral surface, and has a through hole coaxial with the axial direction formed on its inner peripheral surface; An internal gear that is directly or indirectly attached to the other of the seat cushion frame and the seat back frame, has internal teeth meshing with the external teeth provided at least one or more more than the external teeth on its inner peripheral surface, and has a cylindrical boss fixed coaxially with the axial direction formed; A ring that is formed so as to be in contact with the inner periphery of the through hole of the external gear and the outer periphery of the cylindrical boss of the internal gear so that no gap is formed between the cylindrical boss, and is arranged so that a gap is provided with respect to the through hole of the external gear, and the center of the circular outer peripheral surface and the center of the circular inner peripheral surface are eccentrically formed, and has an engaging convex portion or an engaging concave portion on the front side; A pair of wedge-shaped cams that are arranged so as to overlap the front side of the ring, regulate the relative rotation of the external gear and the internal gear by contacting the outer peripheral surface of the cylindrical boss of the internal gear and the inner peripheral surface of the through hole of the external gear, and slide the outer peripheral surface of the cylindrical boss of the internal gear and the inner peripheral surface of the through hole of the external gear to allow relative rotation of the external gear and the internal gear; A rotating shaft that is coaxially and rotatably inserted into the cylindrical boss of the internal gear, engages with the engaging convex portion or the engaging concave portion of the ring to rotate the ring, and has a pressing extension portion that presses the wedge-shaped cam; An elastic body that biases the pair of wedge-shaped cams in a separating direction from each other, and a reclining device characterized by comprising the same.

2. A substantially U-shaped bush is provided on the outer peripheral side of the wedge-shaped cam, The reclining device according to claim 1, wherein the wedge-shaped cam regulates the relative rotation of the external gear and the internal gear by contacting the outer peripheral surface of the cylindrical boss of the internal gear and the inner peripheral surface of the bush, and slides the inner peripheral surface of the bush and the cylindrical boss of the internal gear or the inner peripheral surface of the through hole of the external gear and the bush to allow relative rotation of the external gear and the internal gear.

3. A reclining device for a seat that tiltably holds a seat back frame constituting a seat back with respect to a seat cushion frame constituting a seat cushion, An external gear that is directly or indirectly attached to one of the seat cushion frame and the seat back frame, has external teeth formed on its outer peripheral surface, and has a cylindrical boss coaxial with the axial direction fixedly formed on its inner peripheral surface; An internal gear that is directly or indirectly attached to the other of the seat cushion frame and the seat back frame, has internal teeth that can mesh with the external teeth provided at least one or more more than the external teeth, and has a through hole coaxial with the axial direction formed therein; A ring that is formed to be in contact with the outer peripheral surface of the cylindrical boss of the external gear so as not to create a gap between the inner peripheral surface of the through hole of the internal gear and the outer peripheral surface of the cylindrical boss of the external gear, is arranged so as to provide a gap with respect to the through hole of the internal gear, has the centers of the circular outer peripheral surface and the circular inner peripheral surface formed eccentrically, and has an engaging convex portion or an engaging concave portion on the front side; A pair of wedge-shaped cams that are arranged so as to overlap the front side of the ring and, by contacting the outer peripheral surface of the cylindrical boss of the external gear and the inner peripheral surface of the through hole of the internal gear, regulate the relative rotation of the external gear and the internal gear and slide the outer peripheral surface of the cylindrical boss of the external gear and the inner peripheral surface of the through hole of the internal gear to allow the relative rotation of the external gear and the internal gear; A rotary shaft that is coaxially and rotatably inserted into the cylindrical boss of the external gear, engages with the engaging convex portion or the engaging concave portion of the ring to rotate the ring, and has a pressing extension portion that presses the wedge-shaped cams; An elastic body that biases the pair of wedge-shaped cams in a direction away from each other, characterized by comprising a reclining device.

4. A substantially U-shaped bush is provided on the outer peripheral side of the wedge-shaped cam. The wedge-shaped cam regulates the relative rotation of the external gear and the internal gear by contacting the outer peripheral surface of the cylindrical boss of the external gear with the inner peripheral surface of the bush, and slides the inner peripheral surface of the cylindrical boss of the bush and the external gear or the inner peripheral surface of the through hole of the bush and the internal gear to allow the relative rotation of the external gear and the internal gear. The reclining device according to claim 3, characterized in that it is as described above.

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