Vehicle seat and method for cushioning two spring parts which are movable relative to each other

1. A vehicle seat having a seat part extending in a vehicle length direction (X) and in a vehicle width direction (Y) and having a backrest part and a seat substructure for cushioning and/or damping at least the seat part with respect to a body of a vehicle, in which the seat substructure comprises at least one horizontal spring device having a first spring part, and a second spring part which is movable relative thereto and a deformable fluid spring element for cushioning the seat part with respect to the body in the vehicle length direction (X) and/or in the vehicle width direction (Y), the deformable fluid spring element being arranged with a first connecting region to the first spring part and a second connecting region to the second spring part, wherein the deformable fluid spring element is arranged between the first and second spring parts so as to be deformed solely by the first and second spring parts upon relative movement of the first and second spring parts relative to each other along the at least one of the vehicle length direction (X) and the vehicle width direction (Y), wherein the deformable fluid spring element is subjected to shear forces by the movement of the first and second spring parts relative to each other, and wherein the deformable spring element resists the shear forces.

2. The vehicle seat according to claim 1 , wherein the first and second connecting regions of the deformable fluid spring element are the sole engagement regions by means of which the deformable fluid spring element is deformable upon relative movement of the first and second spring parts relative to each other.

3. The vehicle seat according to claim 1 , wherein the deformable fluid spring element is always held and guided solely by the first and second spring parts arranged with mutual spacing transversely to a main cushioning direction.

4. The vehicle seat according to claim 3 , wherein the first and second connecting regions of the deformable fluid spring element are held on the first and second spring parts so as to be slidable in parallel with each other in the main cushioning direction.

5. The vehicle seat according to claim 3 , wherein the deformable fluid spring element is arranged, at least in the main cushioning direction, so as to oscillate freely between the first and second spring parts.

6. The vehicle seat according to claim 1 , wherein the deformable fluid spring element has an oblong configuration and is fixed to the first and second spring parts by means of each of its most spaced-apart end regions.

7. The vehicle seat according to claim 1 , wherein the deformable fluid spring element is fixed to one of the two spring parts by means of a fixed bearing and to the other of the two spring parts by means of a floating bearing.

8. The vehicle seat according to claim 1 , wherein the deformable fluid spring element has, at one of its ends, a length-compensating device which acts transversely to a main cushioning direction.

9. The vehicle seat according to claim 8 , wherein the length-compensating device comprises a lever element which is arranged hingedly on one of the first and second spring parts.

10. The vehicle seat according to claim 1 , wherein the deformable fluid spring element comprises an oblong, tubular and resilient main body which has a closed cavity which can be filled with a volume of cushioning fluid according to a measured spring path.

11. A method for cushioning a first and a second spring part which are movable relative to each other and belong to a horizontal spring device of a vehicle seat having a seat part and a backrest part, in which the first and second spring parts are cushioned relative to each other by means of a deformable fluid spring element subjected to shear forces by movement of the vehicle seat relative to a vehicle body in at least one of the vehicle length direction (X) and the vehicle width direction (Y), wherein the deformable fluid spring element resists the shear forces, and wherein an internal pressure within the deformable fluid spring element is actively varied from the exterior according to at least one of an intensity of an introduced oscillation and a measured spring path in order to adapt the spring characteristic to the current introduced oscillation.

12. The method according to claim 11 , wherein the internal pressure is actively increased from the exterior either prior to or during a first cushioning movement in a main cushioning direction, whereas the internal pressure is actively reduced either prior to or during a restoring cushioning movement counter to the first cushioning movement in order to prevent a build-up of oscillations due to excessive restoring forces of the deformable fluid spring element.

13. The vehicle seat according to claim 1 , wherein the first and second connecting regions of the deformable fluid spring element are held by the first and second spring parts respectively so as to be moveable in parallel relative to one another in the at least one of the vehicle length direction (X) and the vehicle width direction (Y).

14. The vehicle seat according to claim 1 , wherein the deformable fluid spring element extends in an elongate manner transversely to the at least one of the vehicle length direction (X) and the vehicle width direction (Y).

15. A vehicle seat, comprising:

a seat part extending in a vehicle length direction (X) and in a vehicle width direction (Y); and

a seat substructure, including:

at least one horizontal spring device, including:

a first spring part, wherein the first spring part is connected to the seat part;

a second spring part, wherein the second spring part is connect to a vehicle body; and

a deformable spring element,

wherein a first connecting region of the deformable spring element is connected to the first spring part,

wherein a second connecting region of the deformable spring element is connected to the second spring part,

wherein the deformable fluid spring element is arranged between the first and second spring parts so as to be deformed solely by the first and second spring parts,

wherein movement of the seat part relative to the vehicle body in at least one of the vehicle length direction (X) and the vehicle width direction (Y) subjects the deformable spring element to a shear force, and

 wherein the deformable spring element resists the shear force.

16. The vehicle seat of claim 15 , wherein the first and second connecting regions of the deformable spring element are held by the first and second spring parts respectively so as to be moveable in parallel relative to one another in the at least one of the vehicle length direction (X) and the vehicle width direction (Y).

17. The vehicle seat of claim 15 , wherein the deformable spring element extends in an elongate manner transversely to the at least one of the vehicle length direction (X) and the vehicle width direction (Y).

18. The vehicle seat according to claim 15 , wherein the first and second connecting regions of the deformable spring element are the sole engagement regions by means of which the deformable spring element is deformable upon relative movement of the first and second spring parts relative to each other.

19. The vehicle seat according to claim 15 , wherein the deformable spring element is fixed to one of the two spring parts by means of a fixed bearing and to the other of the two spring parts by means of a floating bearing.

20. The vehicle seat according to claim 15 , wherein the deformable spring element comprises an oblong, tubular and resilient main body which has a closed cavity which can be filled with a volume of cushioning fluid according to a measured spring path.