A clutch unit includes a lever-side clutch part to control transmission and interruption of rotational torque input through lever operation, and a brake-side clutch part to transmit the rotational torque from the lever-side clutch part to an output side, and interrupt rotational torque reversely input from the output side. The brake-side clutch part includes a cover constrained in rotation, an output shaft to output the rotation, an inner ring to receive the rotational torque input from the lever-side clutch part, and a cylindrical roller to control interruption of the rotational torque from the output shaft and transmission of the rotational torque from the inner ring through engagement and disengagement between an outer ring and the output shaft. The inner ring includes a slide gear which meshes with the cover during interruption of the rotational torque and is released from the meshing state during transmission of the rotational torque.

A lifter device includes: an output shaft; a support member supporting the output shaft; an input member coupled to an operation handle; a feed portion transmitting forward and reverse rotation of the input member to the output shaft; a lock portion locking the rotation of the output shaft; and a friction generating portion applying a frictional force to the rotation of the output shaft. A rotating cam of the friction generating portion is a switching structure of switching to: a friction-suppression state when the operation handle is in a neutral position and when the operation handle is turned from the neutral position in a direction of raising the seat; and a friction-on state when the operation handle is turned from the neutral position in a direction of lowering the seat.

A seat height adjustment actuator includes a brake drum fixable to a seat and defining an outer brake race. A rotatable brake hub includes a floor with a shelf, and a wall around the floor with cam surfaces defining an inner brake race. A pinion fixed to the brake hub engages a seat adjustment mechanism through the brake drum. Rolling brake elements wedge between the inner and outer brake races to lock the brake hub at rest. A clutch drum defines an outer clutch race, and includes tabs extending between the brake races to displace the brake rollers, unlocking the brake hub, under actuator input. A centering bias element on the floor simultaneously engages the shelf and a projection of the clutch drum for centering the projection over the shelf at rest. A driver cam receives actuator input and drives rotation of the clutch drum.

A lifter device includes: an output shaft; a support member supporting the output shaft; an input member coupled to an operation handle; a feed portion transmitting forward and reverse rotation of the input member to the output shaft; a lock portion locking the rotation of the output shaft; and a friction generating portion applying a frictional force to the rotation of the output shaft. A rotating cam of the friction generating portion is a switching structure of switching to: a friction-suppression state when the operation handle is in a neutral position and when the operation handle is turned from the neutral position in a direction of raising the seat; and a friction-on state when the operation handle is turned from the neutral position in a direction of lowering the seat. In the friction-on state, a rotating member is pressed against a fixed member and friction is generated.

A clutch unit includes a lever-side clutch part to control transmission of rotational torque input through a lever operation, and a brake-side clutch part to transmit the rotational torque from the lever-side clutch part to an output side, and interrupt rotational torque from the output side. The brake-side clutch part includes an outer ring constrained in rotation, an output shaft configured to output the rotation, a cage arranged between the outer ring and the output shaft to receive the rotational torque from the lever-side clutch part, and a cylindrical roller to control the interruption of the rotational torque from the output shaft and the transmission of the rotational torque input from the cage through engagement and disengagement between the outer ring and the output shaft.

Disclosed is a seat pumping device for a vehicle, the seat pumping device including: a clutch drum turned by receiving torque of a lever and having a plurality of compressing protrusions radially formed along an edge thereof to be spaced apart from each other; a brake drum coupled to the clutch drum and having a circular vertical flange protruding toward the clutch drum, the vertical flange having a plurality of supporting protrusions protruding laterally of the vertical flange to be arranged between the compressing protrusions; and a securing portion provided between the vertical flange and the clutch drum which face each other, the securing portion guiding a relative turning of the clutch drum and the brake drum while blocking a relative translation of the clutch drum and the brake drum.

A stopper is provided with a rotation shaft-side protrusion provided both on an outer circumferential surface of an outer circumferential surface part of a rotation shaft and on an end surface of a ratchet, and protrudes from each of the surfaces, an engagement member slidably supported on the outer circumferential surface, and engages with the rotation shaft-side protrusion in a rotation direction of the rotation shaft, and a support member-side protrusion provided to engage with the engagement member in the rotation direction such that a sliding surface part of a support member is formed concentric with the outer circumferential surface and a portion of the sliding surface part protrudes toward the outer circumferential surface part, wherein the sliding surface part faces the outer circumferential surface part so that the engagement member is slidably interposed between the support member and the outer circumferential surface.

An adjustment assembly or mechanism that permits adjustment of the height and angle of tilt of a vehicle seat includes front and rear latch gears with multiple cogs corresponding to discrete angular positions of the latch gears and consequently discrete heights of the front and rear of the adjustment assembly. The front latch gears pivot about a fixed pivot axis while the rear latch gears pivot about a sliding pivot axis to accommodate tilt angles for the seat. Torsion springs bias the four latch gears to a maximum rotation or pivot position in which the respective ends of the seat are at their highest vertical position. A spindle engages the cogs of the latch gears to hold the latch gears in a particular discrete angular position. Separate front and rear manual actuation levers at the front of the seat can be lifted to release a respective front and rear spindle from a particular cog and allow the driver to adjust the seat position. The independent front and rear adjustment mechanisms allow the driver to place the seat in a wide range of heights and tilt angles, including forward and rearward tilt angles.

A fluttering prevention apparatus for a lever of a pumping device includes: a lever bracket including a first side coupled with a lever, a center portion formed with a hollow hole, and a second side formed with insertion holes; a clutch cam including a first side provided with protruding portions inserted into the insertion holes of the lever bracket; a clutch drum having a first side formed with a seat groove to receive the clutch cam is seated therein; and a spindle coupled to the hollow hole of the lever bracket through center portions of the clutch drum, the clutch cam, and the housing, thereby inhibiting the lever bracket from fluttering with respect to the clutch drum.

A clutch unit includes a lever-side clutch part that controls transmission and interruption of rotational torque input through a lever operation, and a brake-side clutch part that transmits the rotational torque from the lever-side clutch part to an output side, and interrupts rotational torque reversely input from the output side. The brake-side clutch part includes an outer ring, which is constrained in rotation, an output shaft that outputs the rotation, and a cylindrical roller that controls the interruption of the rotational torque reversely input from the output shaft and the transmission of the rotational torque input from the lever-side clutch part through engagement and disengagement between the outer ring and the output shaft. The output shaft includes a slide gear, which meshes with a side plate during interruption of the rotational torque and does not mesh with the side plate during transmission of the rotational torque.