Crash-active headrest

• US 20050127726A1
• Filed: 01/18/2005
• Published: 06/16/2005
• Est. Priority Date: 12/21/2002
• Status: Active Grant

• Current Assignee: Keiper GmbH & Company KG (Johnson Controls International plc)
• Original Assignee: Keiper GmbH & Company KG (Johnson Controls International plc)
• Inventors: Klein, Harald, Hippel, Daniel, Ruess, Georg, Schilling, Jurgen, Bohmer, Michael, Rihlmann, Ali Peter, Wrobel, Darius
• Granted Patent: US 7,070,235 B2
• Time in Patent Office: Days
• US Class Current: 297/216.120
• CPC Class Codes: B60N 2/862 with means for maintaining a desired position when the seat-back is adjusted, e.g. parallelogram mechanisms
• CPC Class Codes: B60N 2/865 providing a fore-and-aft movement with respect to the occupant's head
• CPC Class Codes: B60N 2/888 with arrangements for protecting against abnormal g-forces, e.g. by displacement of the head-rest

Abstract

In a headrest (1) for a vehicle seat, having a carrier (5), at least one upper and lower linkage (11, 15) linked to the carrier (5), which can be pivoted around horizontal axles (7, 17), a impact element (13) linked to the linkages (11, 15) which forms at least one four-bar linkage (19) with the linkages (11, 15) and the carrier (5), and an energy storage device (25), the energy storage device (25) driving the four-bar linkage (19) in the event of a crash, so that the impact element (13) comes out forward from an original position into a crash position that is locked against a backward movement by a crash lock, the upper linkage (11) and the lower linkage (15) are unparallel with respect to one another.

Claims

1. A headrest that is for a vehicle seat and operates advantageously in the event of a crash, the headrest comprising:

at least a four-bar linkage including upper and lower linkages mounted for pivoting relative to a carrier, and an impact element that is operatively connected to the upper and lower linkages for moving away from the carrier in an at least generally forward direction, from an original position to a crash position, in response to pivoting of the upper and lower linkages relative to the carrier;

an energy storage device for driving the linkage so that the impact element moves from the original position to the crash position in response to the crash; and

a crash lock for restricting the impact element from moving from the crash position toward the original position,

wherein the upper and lower linkages are unparallel with respect to one another.

2. A headrest according to claim 1, wherein the lower linkage'"'"'s length and the upper linkage'"'"'s length are different.

3. A headrest according to claim 1, wherein the crash lock is operative for being unlocked, in a predetermined manner, while the impact element is in the crash position, so that the impact element can be moved from the crash position to the original position, whereby the impact element is reset to the original position.

4. A headrest according to claim 3, further comprising a resetting device that is operative, while the impact element is in the crash position, for unlocking the crash lock so that the impact element can be moved to the original position.

5. A headrest according to claim 1, wherein the energy storage device is a spring, the spring is in a first configuration while the impact element is in the original position, the spring is in a second configuration while the impact element is in the crash position, a pawl is mounted for pivoting between first and second positions, and the pawl at least indirectly releasably holds the spring in the spring'"'"'s first configuration while the pawl is in the pawl'"'"'s first position.

6. A headrest according to claim 5, further comprising a movably mounted holding element for releasably holding the pawl in the pawl'"'"'s first position.

7. A headrest according to claim 6, further comprising a control lever that is operatively connected to the carrier so that the control lever is operative in response to the crash to move the holding element so that the holding element releases the pawl, so that the pawl can move to the pawl'"'"'s second position.

8. A headrest according to claim 4, wherein:

the energy storage device includes a spring,

the spring is in a first configuration while the impact element is in the original position,

the spring is in a second configuration while the impact element is in the crash position,

a pawl is mounted for pivoting between first and second positions, and the pawl at least indirectly releasably holds the spring in the spring'"'"'s first configuration while the pawl is in the pawl'"'"'s first position,

a control lever is operatively connected to the carrier for moving between first and second positions,

the pawl is retained in the pawl'"'"'s first position while the control lever is in the control lever'"'"'s first position,

the pawl can move to the pawl'"'"'s second position while the control lever is in the control lever'"'"'s second position,

the resetting device is operative, while the impact element is in the crash position, for moving the control lever from the control lever'"'"'s second position to the control lever'"'"'s first position, so that the headrest can be returned to a state in which;

the impact element is in the original position, the spring is in the spring'"'"'s first configuration, and pawl is in the pawl'"'"'s first position so that the pawl at least indirectly releasably holds the spring in the spring'"'"'s first configuration.

9. A headrest according to claim 8, further comprising a magnet for releasably holding the control lever in the control lever'"'"'s first position.

10. A headrest according to claim 8, wherein the resetting device unlocks the crash lock via the control lever.

11. A headrest according to claim 5, wherein the spring bears against a pivotably mounted restraint sheet that is releasably held by the pawl while the pawl is in the pawl'"'"'s first position.

12. A headrest according to claim 1, wherein:

the original position of the impact element can be either of at least a first position of the impact element and a second position of the impact element,

the first position of the impact element is rearward of the second position of the impact element,

the first position of the impact element is rearward of the crash position of the impact element, whereby the first position of the impact element is comfortable for a user of the vehicle seat,

the second position of the impact element is rearward of the crash position of the impact element, whereby the second position of the impact element is comfortable for a user of the vehicle seat, and

the headrest can be releasably maintained in, and moved between, at least the first position of the impact element and the second position of the impact element.

13. A headrest according to claim 1, wherein:

the crash position of the impact element can be either of at least a first position of the impact element and a second position of the impact element,

the first position of the impact element is rearward of the second position of the impact element,

the crash lock is operative for restricting the impact element from moving from the first position of the impact element toward the original position of the impact element, and

the crash lock is also operative for restricting the impact element from moving from the second position of the impact element toward the original position of the impact element.

14. A headrest according to claim 1, wherein the crash lock is further for being selectively unlocked while the impact element is in the crash position, so that the impact element can be moved from the crash position to the original position, and the headrest further comprises a pawl mounted for pivoting between first and second positions, wherein the pawl is at least substantially unloaded while the impact element is in the crash position, and the pawl is operative for:

holding a restraint element of the impact element and thereby maintaining the impact element in the original position, while the pawl is in the pawl'"'"'s first position and prior to the crash,

releasing the restraint element in response to the crash, so that the energy storage device can drive the linkage so that the impact element moves from the original position to the crash position, and

receiving the restraint element and then releasably holding the restraint element so as to maintain the impact element in the original position, in response to the impact element being moved from the crash position to the original position.

15. A headrest according to claim 14, wherein the pawl has a chamfer for bearing against the restraint element for a predetermined period that occurs while the impact element is being moved from the crash position to the original position.

16. A headrest according to claim 14, wherein the pawl has a pawl jaw with a lip for bearing against the restraint element for a predetermined period that occurs while the impact element is being moved from the crash position to the original position.

17. A headrest according to claim 14, wherein a substantial portion of the restraint element is fitted into an other part of the impact element.

18. A headrest according to claim 17, wherein the other part of the impact element includes a receptacle that is closed with a lid, and the restraint element includes a crooked middle section that is at least partially fitted into the receptacle and engaged by the pawl.

19. A headrest according to claim 14, wherein the energy storage device directly bears on the restraint element.

20. A headrest according to claim 18, wherein the energy storage device directly bears on the restraint element.

21. A headrest according to claim 2, wherein the lower linkage'"'"'s length is greater than the upper linkage'"'"'s length.

22. A headrest according to claim 2, wherein the crash lock is operative for being unlocked, in a predetermined manner, while the impact element is in the crash position, so that the impact element can be moved from the crash position to the original position.

23. A headrest according to claim 4, wherein the resetting device includes a tool that can be inserted lengthwise into the headrest.

24. A headrest according to claim 4, wherein the resetting device includes a button on a movable part of the crash lock.

25. A headrest according to claim 2, wherein the energy storage device is a spring, the spring is in a first configuration while the impact element is in the original position, the spring is in a second configuration while the impact element is in the crash position, a pawl is mounted for pivoting between first and second positions, and the pawl at least indirectly releasably holds the spring in the spring'"'"'s first configuration while the pawl is in the pawl'"'"'s first position.

26. A headrest according to claim 3, wherein the energy storage device is a spring, the spring is in a first configuration while the impact element is in the original position, the spring is in a second configuration while the impact element is in the crash position, a pawl is mounted for pivoting between first and second positions, and the pawl at least indirectly releasably holds the spring in the spring'"'"'s first configuration while the pawl is in the pawl'"'"'s first position.

27. A headrest according to claim 4, wherein the energy storage device is a spring, the spring is in a first configuration while the impact element is in the original position, the spring is in a second configuration while the impact element is in the crash position, a pawl is mounted for pivoting between first and second positions, and the pawl at least indirectly releasably holds the spring in the spring'"'"'s first configuration while the pawl is in the pawl'"'"'s first position.

28. A headrest according to claim 6, wherein the holding element is round and is adjacent a side of the pawl that faces from the pawl'"'"'s closing direction.

29. A headrest according to claim 6, wherein the holding element is round and is carried by a moveable bearing arm.

30. A headrest according to claim 7, wherein the control lever is biased by a spring.

31. A headrest according to claim 8, wherein the spring bears against a pivotably mounted restraint sheet that is releasably held by the pawl while the pawl is in the pawl'"'"'s first position.

32. A headrest according to claim 5, wherein:

the original position of the impact element can be either of at least a first position of the impact element and a second position of the impact element,

the first position of the impact element is rearward of the second position of the impact element,

the first position of the impact element is rearward of the crash position of the impact element, whereby the first position of the impact element is comfortable for a user of the vehicle seat,

the second position of the impact element is rearward of the crash position of the impact element, whereby the second position of the impact element is comfortable for a user of the vehicle seat, and

the headrest can be releasably maintained in, and moved between, the first position of the impact element and the second position of the impact element.

33. A headrest according to claim 5,

the crash position of the impact element can be either of at least a first position of the impact element and a second position of the impact element,

the first position of the impact element is rearward of the second position of the impact element,

the crash lock is operative for restricting the impact element from moving from the first position of the impact element toward the original position of the impact element, and

the crash lock is also operative for restricting the impact element from moving from the second position of the impact element toward the original position of the impact element.

34. A headrest according to claim 5, wherein the crash lock is further for being selectively unlocked while the impact element is in the crash position, so that the impact element can be moved from the crash position to the original position, and wherein the pawl is at least substantially unloaded while the impact element is in the crash position, and the pawl is operative for:

holding a restraint element of the impact element and thereby maintaining the impact element in the original position, while the pawl is in the pawl'"'"'s first position and prior to the crash,

releasing the restraint element in response to the crash, so that the spring can drive the linkage so that the impact element moves from the original position to the crash position, and

receiving the restraint element and then releasably holding the restraint element so as to maintain the impact element in the original position, in response to the impact element being moved from the crash position to the original position.

35. A headrest according to claim 34, wherein:

the pawl has a chamfer for bearing against the restraint element for a predetermined period that occurs while the impact element is being moved from the crash position to the original position,

the pawl has a pawl jaw with a lip for bearing against the restraint element for a predetermined period that occurs while the impact element is being moved from the crash position to the original position,

a substantial portion of the restraint element is fitted into an other part of the impact element, and

the other part of the impact element includes a receptacle that is closed with a lid, and the restraint element includes a crooked middle section that is fitted into the receptacle and engaged by the pawl.

36. A headrest that is for a vehicle seat and operates advantageously in the event of a crash, the headrest comprising:

at least a four-bar linkage including upper and lower linkages mounted for pivoting relative to a carrier, and an impact element that is operatively connected to the upper and lower linkages for moving away from the carrier in an at least generally forward direction, from an original position to a crash position, in response to pivoting of the upper and lower linkages relative to the carrier;

an energy storage device for driving the linkage so that the impact element moves from the original position to the crash position in response to the crash; and

a crash lock for restricting the impact element from moving from the crash position toward the original position,

wherein the crash lock is operative for being unlocked, in a predetermined manner, while the impact element is in the crash position, so that the impact element can be moved from the crash position to the original position, whereby the impact element is reset to the original position.

37. A headrest according to claim 36, further comprising a resetting device that is operative, while the impact element is in the crash position, for unlocking the crash lock so that the impact element can be moved to the original position.

38. A headrest that is for a vehicle seat and operates advantageously in the event of a crash, the headrest comprising:

at least a four-bar linkage including upper and lower linkages mounted for pivoting relative to a carrier, and an impact element that is operatively connected to the upper and lower linkages for moving away from the carrier in an at least generally forward direction, from an original position to a crash position, in response to pivoting of the upper and lower linkages relative to the carrier;

an energy storage device for driving the linkage so that the impact element moves from the original position to the crash position in response to the crash, wherein the energy storage device is a spring, the spring is in a first configuration while the impact element is in the original position, the spring is in a second configuration while the impact element is in the crash position;

a crash lock for restricting the impact element from moving from the crash position toward the original position; and

a pawl mounted for pivoting between first and second positions, wherein the pawl at least indirectly releasably holds the spring in the spring'"'"'s first configuration while the pawl is in the pawl'"'"'s first position.

39. A headrest according to claim 38, further comprising a movably mounted holding element for releasably holding the pawl in the pawl'"'"'s first position, and a control lever that is operatively connected to the carrier so that the control lever is operative in response to the crash to move the holding element so that the holding element releases the pawl, so that the pawl can move to the pawl'"'"'s second position.

40. A headrest that is for a vehicle seat and operates advantageously in the event of a crash, the headrest comprising:

at least a four-bar linkage including upper and lower linkages mounted for pivoting relative to a carrier, and an impact element that is operatively connected to the upper and lower linkages for moving away from the carrier in an at least generally forward direction, from an original position to a crash position, in response to pivoting of the upper and lower linkages relative to the carrier;

an energy storage device for driving the linkage so that the impact element moves from the original position to the crash position in response to the crash;

a crash lock for;

restricting the impact element from moving from the crash position toward the original position, and

being selectively unlocked while the impact element is in the crash position, so that the impact element can be moved from the crash position to the original position; and

a pawl mounted for pivoting between first and second positions, wherein the pawl is at least substantially unloaded while the impact element is in the crash position, and the pawl is operative for;

holding a restraint element of the impact element and thereby maintaining the impact element in the original position, while the pawl is in the pawl'"'"'s first position and prior to the crash,

releasing the restraint element in response to the crash, so that the energy storage device drives the linkage so that the impact element moves from the original position to the crash position, and

receiving the restraint element and then releasably holding the restraint element so as to releasably maintain the impact element in the original position, in response to the impact element being moved from the crash position to the original position.

41. A headrest according to claim 40, wherein the pawl has a chamfer for bearing against the restraint element for a predetermined period that occurs while the impact element is being moved from the crash position to the original position.

42. A headrest according to claim 40, wherein the pawl has a pawl jaw with a lip for bearing against the restraint element for a predetermined period that occurs while the impact element is being moved from the crash position to the original position.

43. A headrest according to claim 40, wherein a substantial portion of the restraint element is fitted into an other part of the impact element.