Reclining device

Abstract

To provide a reclining device which functions without use of a wedge-shaped cam, and can stabilize slide.SOLUTION: A reclining device comprises: an external tooth gear 10; an internal tooth gear 20; a first ring 31 and a second ring 32 which is formed into a toric shape with an outer peripheral center and an inner peripheral center being eccentric, in which a clearance is formed between itself and an open hole 12 of the external tooth gear 10, and which has a contact point contacting a cylindrical boss of the internal tooth gear 20 and the open hole 12 on either left side or right side in a vertical direction at the cylindrical boss; an energization member 70 which energizes the first ring 31 and the second ring 32 in a direction separating from each other; a driving member 60; and a rotary shaft 40 which fits to the driving member 60, and rotates the first ring 31 via the driving member 60.SELECTED DRAWING: Figure 3

Description

Technical Field

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

Background Art

[0002] The present applicant has proposed a reclining device for a seat that holds a seat back tiltably with respect to a seat cushion, a first frame fixed to one of the seat cushion and the seat back, a second frame fixed to the other of the seat cushion and the seat back, an external gear gear connected to the first frame and having external teeth formed on an outer peripheral surface and an external tooth boss portion coaxial with an axial direction on an inner peripheral surface, an internal gear gear connected to the second frame and having internal teeth formed on an outer peripheral surface that can mesh with the external teeth and a cylindrical boss portion coaxial with an axial direction on an inner peripheral surface, a rotating shaft that fits coaxially and rotatably into the external gear gear and revolves one of the external gear gear and the internal gear gear around the gear shaft of the other, a pair of wedge-shaped cams inserted between the cylindrical boss portion and the external tooth boss portion, simultaneously contacting the cylindrical boss portion side and the external tooth boss portion to restrict the rotation of the cylindrical boss portion and the external tooth boss portion, and sliding at least one of the cylindrical boss portion side and the external tooth boss portion side to allow the rotation of the cylindrical boss portion and the external tooth boss portion, a spring member that biases the pair of wedge-shaped cams in a direction of simultaneously contacting the cylindrical boss portion side and the external tooth boss portion side, a disk-shaped member that rotates with the rotation of the rotating shaft, extends in an axial direction, and has a pair of cam pushing wings provided with a taper on a contact surface that pushes the pair of wedge-shaped cams in a direction of non-contact from at least one of the cylindrical boss portion side and the external tooth boss portion side, a leaf spring that presses the disk-shaped member against the pair of wedge-shaped cam sides and causes the tapered contact surface to contact the pair of wedge-shaped cams, and the biasing force is set weaker than that of the spring member (Patent Document 1).

[0003] This reclining device has the effect of making the rotational resistance between the external gear and the internal gear uniform, as the wedge-shaped cam is directly actuated by the cam push vane of a disc-shaped member that is linked to the rotating shaft, thereby making the rotation of the external gear and the internal gear smoother.

[0004] Thus, conventional reclining devices require a wedge-shaped cam. However, using a wedge-shaped cam increases the number of parts and thus the cost. Furthermore, using a wedge-shaped cam reduces the contact area with the cylindrical boss or external tooth boss, resulting in poor sliding performance when subjected to high external loads. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2019-127210 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] Therefore, the present invention has been made in view of these problems, and aims to provide a reclining device that can function without using a wedge-shaped cam and can stabilize sliding. [Means for solving the problem]

[0007] To achieve the above-mentioned objectives, the present invention employs the following means.

[0008] The reclining device of the present invention is A seat reclining device that tiltably holds a seat back frame, which constitutes a seat back, with respect to a seat cushion frame, which constitutes a seat cushion, An external gear is attached directly or indirectly to either the seat cushion frame or the seat back frame, having external teeth formed on its outer circumferential surface and a cylindrical boss formed on its inner circumferential surface that is coaxial with the axial direction, An internal gear is directly or indirectly attached to the other of the seat cushion frame and the seat back frame, and has internal teeth that can mesh with the external teeth, which are provided on the inner circumferential surface at least one more than the external teeth, and has a through hole formed coaxial with the axial direction. Displaced between the inner circumference of the through hole of the internal gear and the outer circumference of the cylindrical boss of the external gear, the first ring is formed in an annular shape with the center of the outer circumference and the center of the inner circumference eccentrically offset, and has an engagement hole formed on the meshing direction side or the opposite side of the meshing direction of the external gear and the internal gear, first spring holes formed on both sides of the engagement hole, and an insertion hole formed as an elongated hole, and a gap is formed between the through hole of the internal gear on the meshing direction side and the opposite side of the meshing direction of the external gear and the internal gear, and when the external gear and the internal gear are locked, the first ring has a contact point that contacts the cylindrical boss and the through hole on either the left or right side in a direction perpendicular to the center of the cylindrical boss of the external gear with respect to the meshing direction of the external gear and the internal gear, The second ring is positioned on the back side of the first ring and is formed in an annular shape with the center of the outer circumference and the center of the inner circumference eccentrically offset. It has a second spring hole provided on the opposite side of the first spring hole to the engagement hole of the first ring, and an insertion projection that is inserted into the engagement hole of the first ring. A gap is formed between the second ring and the through hole of the internal gear on the meshing direction side and the opposite side of the meshing direction of the external gear and the internal gear. When the external gear and the internal gear are locked, the second ring has a contact point that contacts the cylindrical boss and the through hole on either the left or right side in a direction perpendicular to the center of the cylindrical boss of the external gear with respect to the meshing direction of the external gear and the internal gear. A biasing member, the end of which is inserted into the first spring hole of the first ring and the second spring hole of the second ring, respectively, biases the first spring hole and the second spring hole in a direction that separates them, A drive member is coaxially and rotatably fitted into the cylindrical boss of the external gear, and has a fitting hole on its inside and a protrusion that is inserted into the engagement hole of the first ring. A rotating shaft that fits into the drive member and rotates the first ring or the second ring via the drive member, It is characterized by having the following features.

[0009] The present invention provides a reclining device that can maintain both a locked state and an operational state without using a wedge-shaped cam, by using two rings and setting different wedge angles for each ring relative to the direction of rotation, thereby providing a wedge function.

[0010] Furthermore, in the reclining device according to the present invention, A seat reclining device that tiltably holds a seat back frame, which constitutes a seat back, with respect to a seat cushion frame, which constitutes a seat cushion, An external gear is attached directly or indirectly to either the seat cushion frame or the seat back frame, having external teeth formed on its outer circumferential surface and a through hole formed on its inner circumferential surface that is coaxial with the axial direction, An internal gear is directly or indirectly attached to the other of the seat cushion frame and the seat back frame, and has internal teeth that can mesh with the external teeth, which are provided on the inner circumferential surface at least one more than the external teeth, and has a cylindrical boss formed coaxial with the axial direction. Displaced between the inner circumference of the through hole of the external gear and the outer circumference of the cylindrical boss of the internal gear, the first ring is formed in an annular shape with the center of the outer circumference and the center of the inner circumference eccentrically offset, and has an engagement hole formed on the meshing direction side or the opposite side of the meshing direction of the external gear and the internal gear, first spring holes formed on both sides of the engagement hole, and an insertion hole formed as an elongated hole, and a gap is formed between the through hole of the external gear on the meshing direction side and the opposite side of the meshing direction of the external gear and the internal gear, and when the external gear and the internal gear are locked, the first ring has a contact point that contacts the cylindrical boss and the through hole on either the left or right side in a direction perpendicular to the center of the cylindrical boss of the internal gear with respect to the meshing direction of the external gear and the internal gear, The second ring is positioned on the back side of the first ring and is formed in an annular shape with the center of the outer circumference and the center of the inner circumference eccentrically offset. It has a second spring hole provided on the opposite side of the first spring hole to the engagement hole of the first ring, and an insertion projection that is inserted into the engagement hole of the first ring. A gap is formed between the second ring and the through hole of the external gear on the meshing direction side and the opposite side of the meshing direction of the external gear and the internal gear. When the external gear and the internal gear are locked, the second ring has a contact point that contacts the cylindrical boss and the through hole on either the left or right side in a direction perpendicular to the center of the cylindrical boss of the internal gear with respect to the meshing direction of the external gear and the internal gear. A biasing member, the end of which is inserted into the first spring hole of the first ring and the second spring hole of the second ring, respectively, biases the first spring hole and the second spring hole in a direction that separates them, A drive member is coaxially and rotatably fitted into the cylindrical boss of the internal gear, and has a fitting hole on its inside and a protrusion that is inserted into the engagement hole of the first ring. A rotating shaft that fits into the drive member and rotates the first ring or the second ring via the drive member, It is characterized by having the following features.

[0011] The present invention is different from the above-described invention in that a cylindrical boss is provided on the internal gear and a through-hole is formed in the external gear. Similarly, by providing a wedge function on two rings, a reclining device can be provided without having a wedge-shaped cam.

Brief Description of the Drawings

[0012] [Figure 1] FIG. 1 is a schematic view of a vehicle seat 200 to which a reclining device 100 according to the first embodiment is attached. [Figure 2] FIG. 2 is a front view showing the internal structure of the reclining device 100 according to the first embodiment. [Figure 3] FIG. 3 is an exploded perspective view of the reclining device 100 according to the first embodiment. [Figure 4] FIG. 4 is a cross-sectional view taken along the line A-A of the reclining device 100 according to the first embodiment. [Figure 5] FIG. 5 is a front view showing the relationship between the first ring 31, the second ring 32, the cylindrical boss 12, and the through-hole 22 of the reclining device 100 according to the first embodiment. [Figure 6] FIG. 6 is an exploded perspective view of the reclining device 100 according to the second embodiment.

Embodiments for Carrying Out the Invention

[0013] 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 view of a vehicle seat 200, FIG. 2 is a front view showing the internal structure of the reclining device 100, and FIG. 3 is an exploded perspective view of the reclining device 100. Note 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, corresponding components are denoted by the same or similar reference numerals. Also, in FIG. 3, the directions indicated by the arrows in the figure are referred to as "front" and "back", respectively.

[0014] (First Embodiment) The reclining device 100 according to the first embodiment, as shown in Figure 1, is a device that is attached to the seat cushion 210 of a vehicle seat 200 and to the center of tilt of a seat back 220 which is tiltably attached to the seat cushion 210, and provides a tilting function to the seat back 220. Specifically, it is used by being attached directly or indirectly via other mounting plates 230 (hereinafter referred to as "mounting plates, etc.") between the seat cushion frame, which is located inside the seat cushion 210, and the seat back frame, which is located inside the seat back 220.

[0015] The reclining device 100 according to the present invention mainly comprises an external gear 10, an internal gear 20, a first ring 31, a second ring 32, a rotating shaft 40, a drive member 60, a spring 70 as a biasing member, a plate cover 80, and a shaft locking member 90, as shown in Figures 2 to 4. Note that in Figure 2, the rotating shaft 40, the drive member 60, the plate cover 80, and the shaft locking member 90 are omitted to make the internal structure easier to see.

[0016] As shown in Figure 3, the external gear 10 is formed in a disc shape, with external teeth 11 formed on its outer circumferential surface, and a cylindrical boss 12 is provided in the center, as shown in Figure 3. The external gear 10 is provided with a protrusion 13, and is attached to the vehicle seat 200 by welding or the like while fitted into a fitting hole provided in a mounting plate 230 or the like.

[0017] The internal gear 20 is formed in a disc shape with a larger diameter than the external gear 10, and a cylindrical recess is formed so that the external gear 10 can be mounted inside it. Internal teeth 21 (see Figure 2) are formed on the inner circumferential surface of this recess. The internal teeth 21 are formed to be at least one more than the number of teeth of the external teeth 11 of the external gear 10. As shown in Figure 2, the external gear 10 and the internal gear 20 mesh with each other such that the center C1 of the external gear 10 and the center C2 of the internal gear 20 are eccentric as indicated by arrow d1. Therefore, the external gear 10 and the internal gear 20 form a differential gear, and when the internal gear 20 completes one revolution around the external teeth 11, it rotates by the difference in the number of teeth between the internal teeth 21 and the external teeth 11. That is, for example, if there is only one difference in the number of teeth, when the external gear 10 completes one revolution around the internal gear 20, it rotates by the amount of one tooth. As shown in Figure 3, a through hole 22 is provided at the center of the internal gear 20. The internal gear 20 is provided with a protrusion 23, which is fitted into a fitting hole provided in a mounting plate 230 and attached to the vehicle seat by welding or the like.

[0018] The first ring 31 and the second ring 32 are annular members positioned between the inner circumferential surface 22a of the through hole 22 of the internal gear 20 and the outer circumferential surface 12a of the cylindrical boss 12 of the external gear 10, with the first ring 31 and the second ring 32 overlapping each other. The first ring 31 is positioned on the front side relative to the second ring 32. The first ring 31 has an engagement hole 31a on the side in the meshing direction between the external gear 10 and the internal gear 20, or on the opposite side of the meshing direction, into which a projection 63 of a drive member 60 (described later) is inserted, and spring holes are provided on both sides thereof. One of the spring holes is a first spring hole 31b for biasing the first ring 31, and the other is a through hole 31c for passing a spring to bias the second ring 32, and is made as a curved elongated hole so that the second ring 32 can move relative to the first ring 31. As shown in Figure 5, the first ring 31 is formed eccentrically such that the center C3 of the outer circumference and the center C4 of the inner circumference are approximately equal in eccentricity d2 to the eccentricity between the center of the external gear 10 and the center of the internal gear 20. Gaps d3 and d4 are formed between the ring 31 and the through hole 22 of the internal gear 20 on the meshing direction side and the opposite side of the meshing direction. Note that the eccentricity and gaps in Figure 5 are exaggerated for ease of understanding, but in reality, the eccentricity and gaps are much smaller and narrower. Furthermore, when the external gear 10 and the internal gear 20 are locked, the first ring 31 contacts the cylindrical boss 12 and the through hole 22 on either the left or right side (right side in this embodiment) in the direction perpendicular to the center of the cylindrical boss 12 of the external gear 10 with respect to the meshing direction of the external gear 10 and the internal gear 20, forming contact points 31d and 31e, respectively. In this state, the first ring 31 has a wedge angle set on its outer surface relative to the through hole 22. Therefore, by rotating the first ring 31 clockwise (right-hand), the wedge is released and the locked state is resolved. The second ring 32 is positioned on the back of the first ring 31, and the second spring hole 32a is provided on the opposite side of the first spring hole 31b relative to the engagement hole 31a of the first ring 31.Similar to the first ring 31, the second ring 32 is formed eccentrically, as shown in Figure 5, such that the center of the outer circumference C3 and the center of the inner circumference C4 are approximately equal in eccentricity to the center of the outer gear 10 and the center of the inner gear 20. A gap is formed between the second ring 32 and the through hole 22 of the inner gear 20 on both the meshing direction side and the opposite side of the meshing direction. Furthermore, when the outer gear 10 and the inner gear 20 are locked, the second ring 32 contacts the cylindrical boss 12 and the through hole 22 on opposite sides via the contact point of the first ring 31 and the cylindrical boss 12, perpendicular to the center of the cylindrical boss 12 of the outer gear 10 with respect to the meshing direction of the outer gear 10 and the inner gear 20, forming contact points 32d and 32e, respectively. In this state, a wedge angle is set on the outer surface of the second ring 32 at the contact point with respect to the through hole 22. Therefore, by rotating the second ring 32 counterclockwise (leftward), the wedge is disengaged and the locked state is resolved. In this way, the first ring 31 and the second ring 32 in this embodiment do not use a wedge-shaped cam, and the first ring 31 and the second ring 32 themselves have the function of a wedge, moving the external gear 10 and the internal gear 20 in an eccentric direction to lock them and prevent rattling. The second ring 32 has an insertion projection 32f that is inserted into the engagement hole 31a of the first ring 31, and contacts the engagement hole 31a of the first ring 31 on the side with the contact 32d (left side in Figure 5). A projection 63 of the drive member 60, which will be described later, is inserted into this engagement hole 31a, and the first ring 31 and the second ring 32 move via the drive member 60 as the rotation of the rotating shaft 40 occurs.

[0019] The rotating shaft 40 is rotatably positioned coaxially with respect to the cylindrical boss 12 of the external gear 10. The rotating shaft 40 is rotationally driven when adjusting the tilt of the seat back 220, and serrations 41 are provided on the inner cylindrical surface to receive the rotational force of the tilting motor. The rotating shaft 40 has a cylindrical shaft portion 42 that is inserted into a drive member 60, which will be described later, and is provided with a plurality of locking portions 43 that rotate synchronously with the drive member 60.

[0020] The drive member 60 has a fitting hole 61 on its inner circumference that fits with the locking portion 43 of the rotating shaft 40, and is rotated in conjunction with the rotation of the rotating shaft 40. In addition, the outer circumferential surface of the drive member 60 has a projection 63 that is inserted into the engagement hole 31a of the first ring 31. Therefore, the drive member 60, which is rotated by the rotation of the rotating shaft 40, can rotate the first ring 31 and the second ring 32 by pressing the side surface of the engagement hole 31a of the first ring 31 or the insertion projection 32f of the second ring 32 with the projection 63.

[0021] The spring 70, acting as a biasing member, is made of an elastic material and, as shown in Figure 3, has an annular portion 71 and ends 72a and 72b that rise up from the annular portion 71 at a 90° angle. The ends 72a and 72b are inserted into the first spring hole 31b and the second spring hole 32a, respectively, and bias the first spring hole 31b and the second spring hole 32a in a direction that separates them.

[0022] The plate cover 80 is a component that secures the external gear 10, internal gear 20, first ring 31, second ring 32, rotating shaft 40, drive member 60, and spring 70 (which acts as an elastic body) to prevent them from coming off, and its form is not particularly limited. The shaft locking member 90 is a component that locks the rotating shaft 40.

[0023] The reclining device 100 thus manufactured operates as follows: When no force is applied to the rotating shaft 40 and it is not rotating, the first ring 31 and the second ring 32 are biased by the spring 70, causing the outer circumferential surface 12a of the cylindrical boss 12 of the external gear 10 and the inner circumferential surface 22a of the through hole 22 of the internal gear 20 to press and make contact at the contact point. As a result, the relative motion of the internal gear 20 and the external gear 10 is locked, and the seat back 220 is in a locked state.

[0024] From this locked state, if the rotating shaft 40 is rotated counterclockwise, for example in Figure 2, the drive member 60 fitted to the rotating shaft 40 first rotates, and the rotational force of the drive member 60 is transmitted from the protruding portion 63 to the side surface of the engagement hole 31a of the first ring 31, causing the first ring 31 to rotate counterclockwise. This rotation releases the wedge effect formed by the wedge angle created by the outer and inner surfaces of the first ring 31, creating a gap between the contact point between the first ring 31 and the cylindrical boss 12 and the through hole 22, thus releasing the wedge. As a result, a gap is created between the first ring 31 and the cylindrical boss 12 and between the first ring 31 and the through hole 22 of the internal gear 20, allowing the external gear 10 to rotate relative to the internal gear 20. Accordingly, the biasing force of the spring 70 causes the second ring 32 to rotate counterclockwise to fill this gap. In this way, the rotating shaft 40, the first ring 31, and the second ring 32 rotate counterclockwise, sliding together. Thus, the external gear 10, the internal gear 20, and the rotating shaft 40 constitute a differential gear mechanism. In the case of clockwise rotation, the insertion projection 32f of the second ring 32 is pressed, causing the second ring 32 to rotate clockwise. This rotation releases the wedge effect formed by the wedge angle created by the outer and inner surfaces of the second ring 32, creating a gap between the contact point between the second ring 32 and the cylindrical boss 12 and the through hole 22, thus releasing the wedge. As a result, a gap is created between the second ring 32 and the cylindrical boss 12 and between the first ring 31 and the through hole 22 of the internal gear 20, allowing the external gear 10 to rotate relative to the internal gear 20. Consequently, the biasing force of the spring 70 causes the first ring 31 to rotate counterclockwise to fill this gap. In this way, the rotating shaft 40, the first ring 31, and the second ring 32 rotate counterclockwise, sliding together.

[0025] In the reclining device 100 thus manufactured, since the first ring 31 and the second ring 32 are formed in a ring shape, when an external force is applied to the internal gear 20 or external gear 10, it attempts to move the internal gear 20 or external gear 10 in the direction of the external force or reaction force. However, the first ring 31 and the second ring 32 are sandwiched perpendicularly to the outer circumferential surface 12a of the cylindrical boss 12 of the external gear 10 and the through hole 22 of the internal gear 20 with respect to the direction of movement, thereby minimizing the component force and acting as a bearing. As a result, sliding is stabilized and smooth rotation can be ensured.

[0026] Furthermore, since the first ring 31 and the second ring 32 function as wedges, it is possible to use a wedge-shaped cam as in the conventional method, and the reclining device 100 can function without such a requirement.

[0027] Furthermore, when the rotating shaft 40 is rotated, it rotates in accordance with the eccentric direction of the internal gear 20 and the external gear 10, and during rotation, the first ring 31 and the second ring 32 are in contact with most of the outer circumferential surface 12a of the cylindrical boss 12, so that when sliding, the sliding is stabilized and smooth rotation can be ensured.

[0028] (Second Embodiment) Figure 6 shows an exploded perspective view of the reclining device 100 according to the second embodiment. The reclining device 100 according to the second embodiment is identical to the first embodiment except that the external gear 10 has a through hole 15 and the internal gear 20 has a cylindrical boss 25, so a detailed explanation is omitted.

[0029] As shown in Figure 6, the external gear 10 is formed in a disc shape, with external teeth 11 formed on its outer circumferential surface and a through hole 15 in the center.

[0030] The internal gear 20 is formed in a disc shape with a larger diameter than the external gear 10, and has a cylindrical recess formed therein so that the external gear 10 can be mounted inside it, with internal teeth 21 formed on the inner circumferential surface of this recess. The number of internal teeth is at least one more than the number of teeth of the external teeth 11 of the external gear 10, and the internal teeth 21 mesh with the external teeth 11 of the external gear 10 and the internal gear 20 respectively such that the centers of the external gear 10 and the internal gear 20 are eccentric, as in the first embodiment. A cylindrical boss 25 is provided at the center of the internal gear 20, as shown in Figure 6.

[0031] In the second embodiment, the reclining device 100 is moved in the same way as in the first embodiment. When rotated counterclockwise, the drive member 60 fitted to the rotating shaft 40 rotates first, and the rotational force of the drive member 60 is transmitted from the protruding portion 63 to the side surface of the engagement hole 31a of the first ring 31, causing the first ring 31 to rotate counterclockwise. This rotation releases the wedge effect formed by the wedge angle created by the outer and inner surfaces of the first ring 31, creating a gap between the contact point between the first ring 31 and the cylindrical boss 25 and the through hole 15, thus releasing the wedge. As a result, a gap is created between the first ring 31 and the cylindrical boss 25 and between the first ring 31 and the through hole 15 of the external gear 10, allowing the external gear 10 to rotate relative to the internal gear 20. Accordingly, the biasing force of the spring 70 causes the second ring 32 to rotate counterclockwise to fill this gap. In this way, the rotating shaft 40, the first ring 31, and the second ring 32 rotate counterclockwise so as to slide together. Thus, the external gear 10, the internal gear 20, and the rotating shaft 40 constitute a differential gear mechanism. In the case of clockwise rotation, the insertion projection 32f of the second ring 32 is pressed, causing the second ring 32 to rotate clockwise. This rotation releases the wedge effect formed by the wedge angle created by the outer and inner surfaces of the second ring 32, creating a gap between the contact point between the second ring 32 and the cylindrical boss 25 and the through hole 15, thus releasing the wedge. As a result, a gap is created between the second ring 32 and the cylindrical boss 12 and between the first ring 31 and the through hole 15 of the external gear 10, allowing the external gear 10 to rotate relative to the internal gear 20. Accordingly, the biasing force of the spring 70 causes the first ring 31 to rotate counterclockwise to fill this gap. In this way, the rotating shaft 40, the first ring 31, and the second ring 32 rotate counterclockwise, sliding together.

[0032] Furthermore, the present invention is not limited in any way to the embodiments described above, and can be implemented in various forms as long as they fall within the technical scope of the present invention. [Industrial applicability]

[0033] As shown in the embodiments described above, it is primarily industrially applicable as a reclining device for vehicle seats. [Explanation of symbols]

[0034] 10…External gear, 11…External tooth, 12…Cylindrical boss, 12a…Outer surface, 13…Protrusion, 15…Through hole, 20…Internal gear, 21…Internal tooth, 22…Through hole, 22a…Inner surface, 23…Protrusion, 25…Cylindrical boss, 31…First ring, 31a…Engagement hole, 31b…First spring hole, 31c…Through hole, 31d…Contact, 31e…Contact, 32…Second ring, 32a…Second spring hole, 32d…Contact, 32e…Contact Point, 32f... Insertion projection, 40... Rotating shaft, 41... Serration, 42... Shaft section, 43... Locking section, 60... Drive member, 61... Fitting hole, 63... Protruding part, 70... Spring, 71... Annular section, 72a... End section, 80... Plate cover, 90... Shaft locking member, 100... Reclining device, 200... Vehicle seat, 210... Seat cushion, 220... Seat back, 230... Mounting plate

Claims

1. A seat reclining device that tiltably holds a seat back frame, which constitutes a seat back, relative to a seat cushion frame, which constitutes a seat cushion, An external gear is attached directly or indirectly to either the seat cushion frame or the seat back frame, having external teeth formed on its outer circumferential surface and a cylindrical boss formed on its inner circumferential surface that is coaxial with the axial direction, An internal gear is directly or indirectly attached to the other of the seat cushion frame and the seat back frame, and has internal teeth that can mesh with the external teeth, which are provided on the inner circumferential surface at least one more than the external teeth, and has a through hole formed coaxial with the axial direction. Displaced between the inner circumference of the through hole of the internal gear and the outer circumference of the cylindrical boss of the external gear, the first ring is formed in an annular shape with the center of the outer circumference and the center of the inner circumference eccentrically offset, and has an engagement hole formed on the meshing direction side or the opposite side of the meshing direction of the external gear and the internal gear, first spring holes formed on both sides of the engagement hole, and an insertion hole formed as an elongated hole, and a gap is formed between the through hole of the internal gear on the meshing direction side and the opposite side of the meshing direction of the external gear and the internal gear, and when the external gear and the internal gear are locked, the first ring has a contact point that contacts the cylindrical boss and the through hole on either the left or right side in a direction perpendicular to the center of the cylindrical boss of the external gear with respect to the meshing direction of the external gear and the internal gear, The second ring is positioned on the back side of the first ring and is formed in an annular shape with the center of the outer circumference and the center of the inner circumference eccentrically offset. It has a second spring hole provided on the opposite side of the first spring hole to the engagement hole of the first ring, and an insertion projection that is inserted into the engagement hole of the first ring. A gap is formed between the second ring and the through hole of the internal gear on the meshing direction side and the opposite side of the meshing direction of the external gear and the internal gear. When the external gear and the internal gear are locked, the second ring has a contact point that contacts the cylindrical boss and the through hole on either the left or right side in a direction perpendicular to the center of the cylindrical boss of the external gear with respect to the meshing direction of the external gear and the internal gear. A biasing member, the end of which is inserted into the first spring hole of the first ring and the second spring hole of the second ring, respectively, biases the first spring hole and the second spring hole in a direction that separates them, A drive member is coaxially and rotatably fitted into the cylindrical boss of the external gear, and has a fitting hole on its inside and a protrusion that is inserted into the engagement hole of the first ring. A rotating shaft that is fitted to the drive member and rotates the first ring or the second ring via the drive member, A reclining device characterized by having the following features.

2. A seat reclining device that tiltably holds a seat back frame, which constitutes a seat back, relative to a seat cushion frame, which constitutes a seat cushion, An external gear is attached directly or indirectly to either the seat cushion frame or the seat back frame, having external teeth formed on its outer circumferential surface and a through hole formed on its inner circumferential surface that is coaxial with the axial direction, An internal gear is directly or indirectly attached to the other of the seat cushion frame and the seat back frame, and has internal teeth that can mesh with the external teeth, which are provided on the inner circumferential surface at least one more than the external teeth, and has a cylindrical boss formed coaxial with the axial direction. Displaced between the inner circumference of the through hole of the external gear and the outer circumference of the cylindrical boss of the internal gear, the first ring is formed in an annular shape with the center of the outer circumference and the center of the inner circumference eccentrically offset, and has an engagement hole formed on the meshing direction side or the opposite side of the meshing direction of the external gear and the internal gear, first spring holes formed on both sides of the engagement hole, and an insertion hole formed as an elongated hole, and a gap is formed between the through hole of the external gear on the meshing direction side and the opposite side of the meshing direction of the external gear and the internal gear, and when the external gear and the internal gear are locked, the first ring has a contact point that contacts the cylindrical boss and the through hole on either the left or right side in a direction perpendicular to the center of the cylindrical boss of the internal gear with respect to the meshing direction of the external gear and the internal gear, The second ring is positioned on the back side of the first ring and is formed in an annular shape with the center of the outer circumference and the center of the inner circumference eccentrically offset. It has a second spring hole provided on the opposite side of the first spring hole to the engagement hole of the first ring, and an insertion projection that is inserted into the engagement hole of the first ring. A gap is formed between the second ring and the through hole of the external gear on the meshing direction side and the opposite side of the meshing direction of the external gear and the internal gear. When the external gear and the internal gear are locked, the second ring has a contact point that contacts the cylindrical boss and the through hole on either the left or right side in a direction perpendicular to the center of the cylindrical boss of the internal gear with respect to the meshing direction of the external gear and the internal gear. A biasing member, the end of which is inserted into the first spring hole of the first ring and the second spring hole of the second ring, respectively, biases the first spring hole and the second spring hole in a direction that separates them, A drive member is coaxially and rotatably fitted into the cylindrical boss of the internal gear, and has a fitting hole on its inside and a protrusion that is inserted into the engagement hole of the first ring. A rotating shaft that is fitted to the drive member and rotates the first ring or the second ring via the drive member, Equipped with, A reclining device characterized by rotating either the side surface of the engagement hole of the first ring or the insertion projection of the second ring by pressing it depending on the rotation direction of the protruding part of the drive member.

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