An actuation system for a vehicle seat includes a housing and a gear system located in the housing having one or more gears coupled together. The gear of the actuation system have a low actuation efficiency such that the gears move in response to a first input.

An adjustment mechanism for a vehicle seat includes an actuator and a driven member. The actuator is coupled to the driven member to cause the driven member to move or be freed to move in response to activating the actuator.

A vehicle seat may have an angle detection device configured to detect a reclining angle of a seatback, an angle detection reference member configured to serve as a reference for the angle detection device, and a rotation limiting guide unit configured to connect a seat fixing structure to the angle detection reference member and to limit rotation of the angle detection reference member by guiding upward-and-downward and forward-and-rearward movements of the angle detection reference member during tilting of a seat cushion around a hinge structure.

A rotary recline mechanism for allowing reclining movement of a first part relative to a second part, the mechanism comprising: a first gear mechanism comprising first and second gear rings having first and second sets of teeth that engage to lock the first and second parts relative to each other and disengage on operation of an actuator to allow relative movement of the first and second parts by application of a force on one of the parts in a first direction, and a second override gear mechanism to allow relative movement of the first and second parts by application of a force in a second direction while the first and second sets of teeth are engaged.

A recliner for a vehicle seat includes a first gear having a collar part at a center thereof, a second gear being internally in contact with the first gear and configured to eccentrically engage with the first gear, a socket including a first coupling portion having an outer diameter portion coupled to be in contact with an inner diameter portion of the collar part, and a second coupling portion having an inner diameter portion coupled to surround an outer diameter portion of the collar part while being in contact with the outer diameter portion of the collar part, and a pair of wedge cams disposed between the socket and the second gear and configured to restrain or release the socket and the second gear.

A vehicle seat recliner for reclining a seat back with respect to a seat base, includes an internal gear member, an external gear member, a drive member, a lock member, a biasing member, and a cover. The drive member causes relative rotation between the internal gear member and the external gear member. The lock member and the biasing member operate for selectively locking and unlocking relative rotation between the internal gear member and the external gear member. The cover covers an outside of the external gear member. The outside of the external gear member includes fitting projections, wherein the fitting projections project toward the cover, and are arranged concentrically. Each of the fitting projections includes a radial inside fixed to the cover by press-fitting and recess-projection fitting, and includes a radial outside configured to be fitted to a mounting hole of the second frame.

A gear housing includes a first receptacle, a second receptacle, an elongated receptacle, a connecting portion, and a mounting arm. The first receptacle is configured to house a worm wheel. The second receptacle is configured to house an output gear. The elongated receptacle is configured to house a first portion of a shaft of a drive assembly. The elongated receptacle extends at least partly alongside the first receptacle and the second receptacle. The connecting portion is connectable to another housing that houses a second portion of the shaft of the drive assembly. The mounting arm extends outward from the first receptacle. The mounting arm is disposed between circumferentially adjacent fastening components along a periphery of the first receptacle. The first fastening component is disposed at a juncture between the first receptacle and the second receptacle. The second fastening component overlaps a part of the elongated receptacle.

A vehicle seat includes: a seat cushion; a seat back; a frame; a headrest which is provided on an upper end portion of the frame; and a reclining portion wherein: the reclining portion includes: a link supporting the seat back at a swing end section; a sector gear rotated integrally with the link; a lock unit configured to move between an engaging position and a disengaging position for releasing from the engagement with the sector gear and configured to unrotatably hold the sector gear at the engaging position; and a biasing section biasing the lock unit toward the engaging position; and the lock unit includes: a pinion gear meshing with the sector gear at the engaging position and allowing rotation of the sector gear by rotating in a state of meshing with the sector gear; and a gear holding part configured to unrotatably hold the pinion gear.

A vehicle seat assembly for a vehicle includes a bulkhead mountable to a vehicle body structure at a first location. The seat assembly also includes a seat bottom having a seat pan mountable to the vehicle body structure at a second location that is different than the first location. A seat back of the seat assembly includes a frame. A lower end of the frame is pivotably attached to the bulkhead at a pivot point so that the seat back is pivotable relative to the bulkhead and is supported above the seat bottom by the bulkhead when the vehicle seat assembly is mounted to the vehicle body. A recline mechanism has a driving arrangement mounted to one of the bulkhead and the frame and a driven arrangement mounted to the other of the bulkhead and the frame. The recline mechanism is operable to pivot the seat back relative to the bulkhead.

An embodiment manual seatback folding apparatus of an electric seat for a vehicle includes a shaft fastened to a seatback frame, wherein first and second end portions of the shaft are rotatably inserted into first and second seat cushion side frames, respectively, a first rotatable disk including a first locking recess, a second rotatable disk including a second locking recess and a pusher, a first manual control device detachably engaged with the first locking recess, a second manual control device to be connected to the first manual control device through a cable and detachably engaged with the second locking recess, and a switch device mounted on an outer surface of the second seat cushion side frame and configured to perform a switching operation in response to the pusher in a state in which the second rotatable disk is rotated in a folding direction.