A locking mechanism for a recliner assembly. The locking mechanism includes a plate and a pawl. The plate includes a peripheral lip having an interior face that defines a plurality of teeth. The pawl includes first teeth positioned at opposing ends thereof and second teeth positioned between the first teeth. Each of the first teeth has a first flat face and a second flat face. Each of the second teeth has one flat face and one curved face. The pawl is positionable between (i) a first position where the pawl does not engage with the plate and (ii) a second position where the pawl engages with the plate.

An articulation mechanism comprising first and second frames mounted in a rotatable manner with respect to one another and connected together by a gear controlled by an input member (11) actuating an eccentric cam mounted in a rotatable manner in a cylindrical housing integral with the first frame. The cam is formed of two cam parts that are elastically urged towards a position of maximum eccentricity and are movable towards a position of minimum eccentricity during actuation of the input member. A load-spreading washer is mounted in a rotatable manner with play in the cylindrical housing, parallel to the eccentric cam.

A seat reclining device includes: a reclining unit that includes a fixing member fixed to a seat cushion side and a rotating member fixed to the seat cushion side and supported by the fixing member to rotate freely, and that switches freely between a locked state and an unlocked state; a transmission lever supported by the fixing member to rotate freely on the same center as the fixing member; a release operation lever supported on the seat cushion side to rotate freely between lock operation and unlocking operation positions; a link which includes a protruding portion, in which each end portion of the link is supported by one of the transmission and release operation levers to rotate freely, and which switches the reclining unit from the locked state to the unlocked state; and a holding plate that includes an unlock holding portion.

A seat adjustment mechanism may include a recliner mechanism, a recliner handle, a hub and an unlock lever. The recliner mechanism 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 recliner handle is rotatable between locked and unlocked positions to move the recliner mechanism between the locked and unlocked states. The hub may transmit motion of the recliner handle to the recliner mechanism as the recliner handle moves between the unlocked and locked positions. The unlock lever may move the recliner mechanism between the locked and unlocked states. Rotation of the recliner handle may cause corresponding rotation of the hub and the unlock lever. However, the unlock lever may move the recliner mechanism into the unlocked state without causing corresponding rotation of the hub and the recliner handle.

A method of producing a seat reclining apparatus includes connecting one of a first connecting portion and a second connecting portion of a biasing member to associated one of a base member and a lock drive member, with a lock member and the lock drive member supported on the base member, thereby bringing the biasing member to a temporarily held state; mounting the ratchet to the base member so as to cover the biasing member in the temporarily held state; and fixing the other of the first connecting portion and the second connecting portion to the other of the base member and the lock drive member through an opening which is formed in one of the base member and the ratchet, thereby bringing the biasing member to the biasing state from the temporarily held state.

A disc recliner comprises a fixed guide plate coupled to a rotatable tooth plate. Pawls are movable between a first position interlocking the guide plate and tooth plate in a locked condition and a second position disengaged from the tooth plate in an unlocked condition to allow pivotal movement therebetween. A shaft extends through the guide plate and the tooth plate and a cam is fixedly mounted on the shaft for engagement with the pawls. A drive nut is fixedly mounted to the guide plate for rotation therewith. A drive screw is fixedly mounted to the shaft and matingly engaged with the drive nut wherein rotation of the shaft rotates the drive screw and the drive nut causes lateral movement of the shaft and cam along an axis to drive the pawls between the first and second positions thereby actuating the disc recliner between a locked and unlocked conditions.

A hinge mechanism for a vehicle seat, allowing adjustment of the tilt of a seat backrest relative to a seat cushion. The hinge mechanism has two plates, the first plate containing base gear teeth on an edge directed inward, a set of first elements cooperating with a first control cam biased by first springs, a set of second elements cooperating with a second control cam biased by second springs, and a control hub for moving the control cams toward an unlocking position against the biasing of the first and second springs. The set of first elements have teeth offset angularly by at most a half-tooth relative to teeth of the set of second elements, thereby obtaining a small locking pitch.

A seat reclining device includes: a reclining unit that includes a fixing member fixed to a seat cushion side and a rotating member fixed to the seat cushion side and supported by the fixing member to rotate freely, and that switches freely between a locked state and an unlocked state; a transmission lever supported by the fixing member to rotate freely on the same center as the fixing member; a release operation lever supported on the seat cushion side to rotate freely between lock operation and unlocking operation positions; a link which includes a protruding portion, in which each end portion of the link is supported by one of the transmission and release operation levers to rotate freely, and which switches the reclining unit from the locked state to the unlocked state; and a holding plate that includes an unlock holding portion.

A vehicle seat includes a stopping structure that stops forward tilting rotation of a seatback between the seatback and a base on a floor. The stopping structure includes a stopping portion provided on one of the seatback or the base, and a stopper that is provided in a state supported in a cantilevered manner on the other of the seatback or the base, and that extends to a position overlapping with the stopping portion in a seat width direction. The stopping structure is configured to stop the forward tilting rotation of the seatback by abutment of the stopping portion and the stopper. A deformation inhibiting member that minimizes deformation in the seat width direction from the stopper abutting against the stopping portion following forward tilting rotation of the seatback, is provided on the other of the seatback or the base.

A seat adjustment mechanism may include a recliner mechanism, a recliner handle, a hub and an unlock lever. The recliner mechanism 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 recliner handle is rotatable between locked and unlocked positions to move the recliner mechanism between the locked and unlocked states. The hub may transmit motion of the recliner handle to the recliner mechanism as the recliner handle moves between the unlocked and locked positions. The unlock lever may move the recliner mechanism between the locked and unlocked states. Rotation of the recliner handle may cause corresponding rotation of the hub and the unlock lever. However, the unlock lever may move the recliner mechanism into the unlocked state without causing corresponding rotation of the hub and the recliner handle.