An assembly group of a vehicle seat comprises a tube element having a tube section extending along a longitudinal direction and a bead section formed on the tube element and radially protruding with respect to the tube section. An attachment part is connected in a torsionally locked manner to the tube element and has a planar section and a first opening formed in the planar section, wherein the tube element extends through the first opening such that the tube element with the bead section abuts the planar section of the attachment part. The attachment part comprises at least a second opening separate from the first opening. The bead section comprises at least one protrusion element engaging with the at least one second opening for torsionally locking the tube element with respect to the attachment part.

A seat cushion device capable of adjusting hardness of a seat cushion including a seating surface, on which a user is seated, includes a recessed part that is formed in a back surface of the seating surface in the seat cushion, a left plate that faces a back surface of a left thigh holding part of the seating surface, on which a left leg thigh of the user is located, and that is movable inside the recessed part vertically, a right plate that faces a back surface of a right thigh holding part of the seating surface, on which a right leg thigh of the user is located, and that is movable inside the recessed part vertically, and a gap adjustment mechanism that moves the left plate and the right plate vertically in an independent manner, and that can adjust a clearance from the back surface of the seating surface.

Vehicle seat (1) having a seat part (2) and a backrest (3), wherein the supporting structure (44) of the seat part or the backrest, in particular the side part thereof, integrally has at least one spring element (40, 31) a pivot point (P) and/or a safety belt connection.

The seat frame has a left and a right link, a left and a right side part and a transverse tube which connects the two side parts. The links are connected to the transverse tube for conjoint rotation. The transverse tube has a main tube located between the side parts, a left end piece assigned to the left side part and a right end piece assigned to the right side part. The main tube is connected to the two end pieces in respective overlapping regions. The main tube is manufactured from a material, preferably from steel, which has an at least 20% higher tensile strength than the material of the end pieces.

The present invention relates to a seat five-link structure (A), comprising a bottom support (1), a wall plate (3), a first front link (4), a second front link (5) and a rear link (2), wherein the bottom support (1) is pivotally connected with the first front link (4) through a first pivot axis (O.sub.1), the first front link (4) is pivotally connected with the second front link (5), the second front link (5) is pivotally connected with the wall plate (3), and the rear link (2) is pivotally connected with the bottom support (1) through a second pivot axis (O.sub.2) and is pivotally connected with the wall plate (3); a first electric motor (8) configured to output a first external force for driving the first front link (4) to rotate around the first pivot axis (O.sub.1); and a second electric motor (12) configured to output a second external force for driving the rear link (12) to rotate around the second pivot axis (O.sub.2). The seat five-link structure (A) according to the present invention may have a larger adjustment range of an inclination angle and a seat height, which is beneficial to the realization of a zero-gravity function and allows an occupant better vision and better comfort.

A vehicle seat includes: a seat cushion on which n occupant is to be seated; and a seat back that is configured to support a back of the occupant. The seat cushion includes: a seat surface that is configured to support a pelvis to thighs of the occupant; a seat surface frame that forms a frame of the seat cushion; a seat surface spring that is coupled to the seat surface frame on a vehicle front side and supports the seat surface; a lifter cross member that extends in a vehicle width direction on a vehicle rear side of the seat cushion and is configured to lift up and down the seat back and the seat cushion; and a spring cross member that is liftably provided on a vehicle lower side of the lifter cross member, extends in the vehicle width direction, and is coupled to the seat surface spring.

A vehicle seat includes a seat frame assembly that defines a skeleton of the vehicle seat, and a height adjusting mono-post module that supports a lower portion of the seat frame assembly and is height-adjustable to adjust a height of the seat frame assembly.