Provided is a reclining device that achieves effective prevention of abnormal sound while permitting a clearance to exist between a cam and a connecting rod. A reclining device includes: a pair of reclining mechanisms each having an internal gear and a cam; a connecting rod coaxially coupled to the cam and being rotatable together with the cam; and a resin bush having a fit hole to receive a fitting part at a portion adjacent to each end of the connecting rod. The resin bush is placed in a bush insertion hole in contact with an inner surface of the bush insertion hole of the internal gear to retain the connecting rod at such a position to the cam that a clearance exists between an inner surface of a rod insertion hole of the cam and an outer surface of the connecting rod.

A seat reclining device includes a ratchet, a guide, and pawls for locking relative rotation between the ratchet and the guide. The ratchet has a second convex portion protruding so as to abut against a ride-up protrusion of a main pawl. The second convex portion has, only in a partial region thereof in the rotation direction, a relief concave portion configured to avoid abutment in the rotation direction between the ride-up protrusion and the second convex portion.

A brake device for a motor vehicle seat is composed of a brake assembly, a tooth assembly, and a lever assembly. The brake assembly includes a housing, a pinion shaft, a braking component, and a drive wheel that are structured to be self-held in an assembled state by mechanical interaction thereamong. The tooth assembly includes a holder plate and a tooth plate that are structured to be self-held in an assembled state by mechanical interaction therebetween. The lever assembly includes an input lever, a cover, a coil spring, and a lever bracket that are structured to be self-held in an assembled state by mechanical interaction thereamong. The brake assembly, the tooth assembly, and the lever assembly are arranged and assembled together in an axial direction.

A drive bush configured to circumferentially rotate and drive a pair of wedge members in an eccentric space includes a cylindrical portion rotatably supported inside a boss portion of an internal tooth constituting member, a flange portion integrally formed at a first end portion in the axial direction of the cylindrical portion so as to face one side surface side of the wedge members, and a pushing portion integrally provided on the outer peripheral side of the flange portion, and configured to release a wedge effect by circumferentially pushing the wedge members. The inner surface of the cylindrical portion is integrally formed with a wall portion, and the wall portion is formed with, in the middle thereof, a female spline teeth meshing with the output shaft of a motor. The cylindrical portion, the wall portion including the female spline teeth and the flange portion have substantially the same thickness.

A seatback adjustment assembly may include a recliner heart, an attachment plate, and a lever. The recliner heart is operable in an unlocked state permitting relative rotation between a seatback and a seat bottom and a locked state preventing relative rotation between the seatback and the seat bottom. The attachment plate is rotationally fixed to the recliner heart. The lever is rotatable between a first state in which the lever is engaged with the attachment plate and a second state in which the lever is disengaged from the attachment plate. When lever is in the first state and the recliner heart is in the unlocked state, rotation of the recliner heart causes corresponding rotation of the seatback relative to the seat bottom. However, the seatback is configured to rotate relative to the seat bottom without causing corresponding rotation of the recliner heart when the lever is in the second state.

A vehicle seat reclining device includes: a ratchet and a guide assembled to be rotatable relative to each other; a plurality of pawls respectively supported by a plurality of corresponding pairs of guide walls of the guide and configured to mesh with the ratchet; and a cam configured to press the pawls in a radial direction by a biasing force of a lock spring. The guide has: welding dowels configured to be welded to a seat frame, the respective welding dowels being formed between the respective pairs of guide walls; and a hooking hole formed between a specific pair of guide walls, an end portion of the lock spring being hooked in the hooking hole. In a state before the welding dowels are welded to the seat frame, a width between the specific pair of guide walls is larger than a width between another pair of guide walls.

A vehicle seat, including a seat underframe and a backrest mounted pivotably with respect to the seat underframe about a backrest pivot axis, the inclination of which backrest may be adjusted in a comfort range by pivoting about the backrest pivot axis by a fitting arrangement. The fitting arrangement is provided on a first of two longitudinal backrest sides of the backrest and a locking device is provided remote from the first longitudinal backrest side, which locking device is provided to lock the backrest so as to prevent pivoting about the backrest pivot axis beyond the comfort region in the event of a crash and which is coupled to the fitting arrangement to actuate the locking device when the backrest is actuated beyond the comfort region and to release a locking provided by the locking device by actuating the fitting arrangement.

A vehicle seat, including a seat underframe and a backrest mounted pivotably with respect to the seat underframe about a backrest pivot axis, the inclination of which backrest may be adjusted in a comfort range by pivoting about the backrest pivot axis by a fitting arrangement. The fitting arrangement is provided on a first of two longitudinal backrest sides of the backrest and a locking device is provided remote from the first longitudinal backrest side, which locking device is provided to lock the backrest so as to prevent pivoting about the backrest pivot axis beyond the comfort region in the event of a crash and which is coupled to the fitting arrangement to actuate the locking device when the backrest is actuated beyond the comfort region and to release a locking provided by the locking device by actuating the fitting arrangement.

A seat reclining device for a vehicle is configured such that an operating surface section and a projection of a pole are disposed at locations separate from each other along the radial direction of a body surface section, and are half-punched from the body surface section in one direction along the axial direction so as to form projections. A pressed surface section of the pole is provided on an edge surface of the body surface section formed on the other side in the axial direction of the operating surface section along with the half-punched projection of the operating surface section.

An internal gear includes a thin annular portion and a thick annular portion whose outside diameters are the same and whose inside diameters are different are continuously provided integrally in an axial direction, and an outer peripheral surface of the thin annular portion and the thick annular portion is formed in a substantially L shape in a flush cross section. Therefore, a conventionally substantially convex section formed with the memory internal teeth does not become the weak point in terms of strength. An axial outer end surface of the thick annular portion of the internal gear is formed to be substantially flat, and the coupling cover member is fixed to the thick annular portion to be coupled to a frame of a seat cushion or a seat back.