Suspension device for a vehicle seat, comprising an upper suspension portion and a lower suspension portion, which are interconnected by a first swivel connector and a second swivel connector, and the first and the second swivel connector are pivoted in each case about a swivel pin in the case of an oscillating movement of the upper suspension portion relative to the lower suspension portion, wherein a first toothed wheel element which is rotatable about a first axis of rotation is arranged on the first swivel connector for adjusting a position of a first spring unit, by means of which a spring force and a spring rate of the suspension device can be changed, the first toothed wheel element being in operative contact with a second toothed wheel element which is rotatable about a second axis of rotation.

The invention relates to a seat arrangement for a vehicle, in particular for a fork-lift truck, the seat arrangement having a first spring part, on which a vehicle seat is arranged, and a second spring part, which can be moved relative to the first spring part by means of a connecting unit and is connected to the body, the relative movement of the first spring part to the second spring part being sprung by means of a spring unit, the spring unit and the connecting unit being arranged laterally on the first spring part.

An active system and a computer-implemented method for reducing vibrations of seats in a vehicle is described. The system and method adjust a damping and/or a stiffness of a vibration damper based on system input signals from the vehicle or seat system. The signals include one or more of a signal associated with a user weight, a signal associated with time-dependent movement of a vehicle frame, and a signal associated with time-dependent movement of a seat back or a seat pan. The damping or the stiffness are adjusted by a closed loop control.

A body weight adjustment mechanism for automatic adjustment to a balanced point is provided to improve vibration absorption characteristics and impact absorption characteristics. A torsion angle of a lower frame-side torsion bar when an upper frame is at a balanced point is found in advance, a torsion angle of the lower frame-side torsion bar in a state in which a person is seated is detected, the detected torsion angle is compared with the aforesaid balanced point torsion angle, a control signal is sent to an elastic force adjusting unit, and torsion angles of upper frame-side torsion bars are adjusted so that the torsion angle of the lower frame-side torsion bar becomes equal to the balanced point torsion angle. The upper frame can be set to an appropriate position in an initial state and a static state in which a person is seated and vibration and impact absorption characteristics are improved.

There are improved a vibration absorption characteristic and an impact absorption characteristic. A seat suspension mechanism set so that links of a first link mechanism on a base frame side and links of a second link mechanism on a seat support frame side, between which an intermediate frame is put, differ in operating angles, that is, so that the links of the second link mechanism operate in the range of an angle closer to a vertical to a front-rear direction of a vehicle body. This allows front-rear movement of the seat support frame through the second link mechanism to mainly respond to input vibrations of front-rear movement to thereby improve a vibration absorption characteristic and an impact absorption characteristic in the front-rear direction.

A kinetic seat cushion assembly that rotates based on a force applied on an occupant seated therein is provided. The kinetic seat cushion assembly includes a primary seat cushion frame, a secondary seat cushion frame, a seat cushion tilt mechanism coupling the secondary seat cushion frame to the primary seat cushion frame such that the secondary seat cushion frame is movable with respect to the primary seat cushion frame, and a front pivot mechanism that pivotally couples a front portion of the primary seat cushion frame to a front portion of the secondary seat cushion frame.

An air suspension apparatus for vehicle seats includes an air shutter connected to a supply port of a control valve configured to supply air so as to adjust the opening degree of an inner air channel through which air supplied to the control valve passes.

A kinetic seat assembly that rotates based on a force applied on an occupant seated therein is provided. The kinetic seat assembly includes a primary seat cushion frame, a primary seat back frame, a secondary seat cushion frame pivotally connected to the primary seat cushion frame, and a secondary seat back frame pivotally connected to the primary seat back frame. The kinetic seat assembly further includes a front pivot mechanism for damping movement between the primary seat cushion frame and the secondary seat cushion frame in a kinetic seat vertical direction, and an upper pivot mechanism for damping movement between the primary seat back frame and the secondary seat back frame in a kinetic seat longitudinal direction.

A seat adjusting structure includes a seat body. A damping force unit is installed at an upper end of the seat body, and a cab connecting plate is installed at a lower end of the seat body. An electronic controller and a seat weight sensor are installed between the damping force unit and the cab connecting plate. A rigidity unit and an operator presence indicator are installed at a lower part of the damping force unit, and a seat damper is installed above the cab connecting plate. The operator presence indicator detects whether an operator exists, while the seat weight sensor detects whether the weight of the operator is within a set range. The electronic controller receives detection signals from the operator presence indicator and the seat weight sensor and controls the damping force unit and the rigidity unit to adjust the rigidity and damping force of the seat damper.

A vehicle seat comprising a seat part extending in the vehicle longitudinal direction (X) and in the vehicle transverse direction (Y) and including a backrest part is provided. The vehicle seat includes a seat substructure for suspending and/or damping at least the seat part with respect to the body of a vehicle. The seat substructure comprises at least one horizontal suspension device that includes a body-side lower part and a seat-part-side upper part displaceable with respect thereto. A coupling device is arranged interactively between the seat-part-side upper part and the body-side lower part, and includes a deformable suspension element as a first coupling element and a bearing and deformation device as a further coupling element.