Height adjustment device of a vehicle seat and a vehicle seat fitted with it

• US 20080197684A1
• Filed: 02/05/2008
• Published: 08/21/2008
• Est. Priority Date: 02/15/2007
• Status: Active Grant

• Current Assignee: Festo AG & Company KG (Festo GmbH & Company KG)
• Original Assignee: Festo AG & Co.
• Inventors: Sailer, Steffen, Geiger, Simon, Ott, Helmut
• Granted Patent: US 7,770,974 B2
• Time in Patent Office: Days
• US Class Current: 297/344.16
• CPC Class Codes: B60N 2/501 actively controlled suspension, e.g. electronic control
• CPC Class Codes: B60N 2/505 Adjustable suspension including height adjustment
• CPC Class Codes: B60N 2/508 Scissors-like structure
• CPC Class Codes: B60N 2/525 using gas

Abstract

A height adjustment device of a vehicle seat comprises a control valve means for governing the degree of filling of a compressed air actuator. Following an alteration in the weight to be carried by the compressed air actuator there is a relative switching over movement between a component bearing a control cam slide and a component bearing an actuating member entailing the switch over of the control valve means. The relative switching over movement is a linear movement, the two components bearing the slide and the actuating member being guided for relative sliding linear motion in the direction of the switch over movement. Furthermore a vehicle seat having such a height adjustment device is provided.

Claims

1. A height adjustment device of a vehicle seat, which comprises a control valve means serving for governing the degree of filling of at least one compressed air actuator holding the seat body at a desired height and thereby providing a vertical elastic supporting action, at least one actuating member cooperating with at least one control cam slide being associated with the control valve means in such a manner that in accordance with use dependent alteration of the weight to be borne by the at least one compressed air actuator a relative switching over movement causing the switching over of the control valve means takes place between a component bearing the at least one control cam slide and another component bearing the associated actuating member, characterized in that the relative switching over movement is a linear movement wherein the said two components bearing the at least one control cam slide and the at least one actuating member are guided in the direction of the switching over movement relatively to one another in a linearly slidable manner.

2. The device as set forth in claim 1, characterized in that the at least one control cam slide is arranged on a control carriage which is a component of a linear unit which also exhibits a guide body, on which the control carriage is borne by linear guide means for linear movement in the direction of the switching over movement and which bears the at least one actuating member for the control valve means.

3. The device as set forth in claim 2, characterized in that the guide body bears the control valve means.

4. The device as set forth in claim 2, characterized in that the guide body delimits a socket space in which the control carriage is arranged in a slidable manner.

5. The device as set forth in claim 4, characterized in that the guide body is tubular, its inner space defining the socket space.

6. The device as set forth in claim 4, characterized in that the socket space and the control carriage have a mutually matching non-circular cross section.

7. The device as set forth in claim 2, characterized in that the control carriage and the guide body are mounted together in a manner avoiding relative rotation.

8. The device as set forth in claim 2, characterized in that the guide body and the control carriage have attachment means assigned to them, which serve for the attachment to vehicle seat components moving closer together or moving apart in the course of alteration of the height of a carried seat body.

9. The device as set forth in claim 8, characterized in that the attachment means render possible a pivotal connection with the associated vehicle seat component.

10. The device as set forth in claim 2, characterized in that the control carriage is arranged on a setting member by whose operation the control carriage is able to be reset in the direction of the switching over movement by performing an adjustment movement in order to change the height desired for the seat body.

11. The device as set forth in claim 10, characterized in that the setting member is designed in the form of a setting lead screw which screwingly engages the control carriage and by rotating actuation of which the control carriage is able to be linearly shifted to execute the adjustment movement.

12. The device as set forth in claim 11, characterized in that the threaded engagement between the control carriage and the setting lead screw is designed with a self-locking action.

13. The device as set forth in claim 11, characterized in that a holder is present fixed or able to be fixed to a vehicle seat component, on which holder the setting lead screw is supported in a manner allowing rotation but preventing axial movement.

14. The device as set forth in claim 10, characterized in that an electrical drive is assigned to the setting member for its operation.

15. The device as set forth in claim 14, characterized in that the electrical drive comprises an electric motor and a transmission.

16. The device as set forth in claim 13, characterized in that an electrical drive is assigned to the setting member for its operation wherein the holder bears the electrical drive.

17. The device as set forth in claim 14, characterized by at least one manually operated electrical switch for the activation of the electrical drive causing the adjustment movement.

18. The device as set forth in claim 2, characterized in that the at least one actuating member is arranged in an adjustable manner on the guide body for performing a resetting movement in the direction of the switching over movement and can be set in the different positions, in order to be able to modify the desired height of the seat body by an alteration of the relative position between the at least one actuating member and the guide body.

19. The device as set forth in claim 18, characterized in that the at least one actuating member is arranged on an adjustment carriage, said adjustment carriage being able to be linearly shifted with regard to the guide body in the direction of the switching over movement while performing the adjustment movement and being able to be held in different positions.

20. The device as set forth in claim 19, characterized in that the control valve means is arranged on the adjustment carriage.

21. The device as set forth in claim 19, characterized in that a setting member engages the adjustment carriage by whose operation the adjustment carriage may be adjusted in the direction of the switching over movement in relation to the guide body.

22. The device as set forth in claim 21, characterized in that the setting member is in the form of a bowden cable.

23. The device as set forth in claim 21, characterized in that a manual or power drive means is assigned to the setting member for the actuation thereof.

24. The device as set forth in claim 23, characterized in that an electrical drive or a hand wheel is provided as the drive means.

25. The device as set forth in claim 1, characterized in that the control valve means is designed for mechanical activation, the at least one actuating member being engaged with and running along the assigned control cam slide in the course of the switching over movement.

26. The device as set forth in claim 21, characterized in that the at least one actuating member is constituted by a rolling body which is arranged in a rotatable manner between the assigned control cam slide and a valve member of the control valve means.

27. The device as set forth in claim 1, characterized in that a discharge valve is present rendering possible venting of the at least one compressed air actuator bypassing the control valve means.

28. The device as set forth in claim 1, characterized in that the control valve means includes two control valves each with its own control cam slide assigned to it.

29. The device as set forth in claim 28, characterized in that the two control cam slides are arranged on the control carriage in a juxtaposed manner in longitudinal parallelism.

30. The device as set forth in claim 28, characterized in that the two control cam slides are arranged in a juxtaposed manner athwart the direction of the switching over movement.

31. The device as set forth in claim 30, characterized in that the two control cam slides are essentially coplanar.

32. The device as set forth in claim 2, characterized in that the at least one actuating member of the control valve means cooperates through at least one wall opening in the guide body with the respectively assigned control cam slide.

33. The device as set forth in claim 1, characterized in that the control valve means has a single control valve which dependent on the position of switching is able to keep the degree of filling of the at least one compressed air actuator constant, to increase it or to reduce it, the position of switching being predetermined by a single control cam slide, which cooperates with an actuating member assigned to this control valve.

34. The device as set forth in claim 33, characterized in that the control cam slide extends on the control carriage in a non-linear fashion in the direction of the switching over movement with the result that the actuating member is displaced on running along in the control cam slide athwart the direction of the switching over movement.

35. The device as set forth in claim 34, characterized in that the single control valve is a flat spool valve and as a valve member it has a flat spool able to slide athwart the direction of the switching over movement, such spool being actuated by the assigned actuating member.

36. The device as set forth in claim 35, characterized in that the flat spool and its mating body stationarily arranged in relation to the guide body of the control valve consist of ceramic material.

37. A vehicle seat comprising a seat body, which is arranged on a seat bracket having a height adjustment device and having at least one compressed air actuator by which the seat body is able to be positioned at different heights and is able to be resiliently vertically maintained on the respectively set height, the seat bracket having at least two support elements varying the distance between them during vertical movement of the seat body, one support element having at least one control cam slide kinematically coupled with it, such control cam slide so cooperating with at least one actuating member kinematically coupled with the other support element and assigned to a control valve means serving for the control of the degree of filling of the at least one compressed air actuator that following a use dependent alteration of the weight carried by the at least one compressed air actuator there is a relative switching over movement between the components bearing the at least one control cam slide and the actuating member assigned thereto causing a switch over of the control valve means, characterized in that the relative switching over movement is a linear movement wherein the component carrying the at least one control cam slide is a control carriage and the component carrying the assigned actuating member constitutes a guide body whereon the control carriage is arranged linearly slidable in the direction of the switching over movement.