Height-adjustable vehicle seat having a crash locking unit

1. A vehicle seat for being mounted to a vehicle structure, and for operating advantageously in the event of a crash of predetermined magnitude, the vehicle seat comprising:

at least one multi-bar linkage, wherein the multi-bar linkage includes at least four link mechanisms, wherein prior to the crash of predetermined magnitude the multi-bar linkage is effective as a four-bar linkage for setting the seat's height, and wherein the at least four link mechanisms includes at least

(a) a frame for being fixed with respect to the vehicle structure,

(b) a rocker, and

(c) a link mechanism positioned between the frame and the rocker;

a crash locking unit for locking at least the frame and the rocker to one another in the event of the crash of predetermined magnitude; and

a second locking unit, wherein

for two adjacent link mechanisms of the at least four link mechanisms, the second locking unit provides a frictional interaction by way of which the second locking unit rigidly connects the two adjacent link mechanisms together prior to the crash of predetermined magnitude,

the second locking unit is operative for opening after a limit force is exceeded in response to the crash of predetermined magnitude, so that relative movement can occur between the two adjacent link mechanisms, and

the second locking unit includes

(a) a locking bar pivotably mounted on a first of the two adjacent link mechanisms,

(b) a counterpart on a second of the two adjacent link mechanisms, and

(c) a spring between the locking bar and the first of the two adjacent link mechanisms.

2. The vehicle seat as claimed in claim 1 , wherein:

the multi-bar linkage is operative for at least temporarily becoming effective as a five-bar linkage in response to the crash of predetermined magnitude, and

the crash locking unit is operative so that the locking, which is provided by the crash locking unit in response to the crash of predetermined magnitude, causes the multi-bar linkage to become effective as a rigid three-bar linkage, whereby the multi-bar linkage becomes effective as the rigid three-bar linkage in response to the crash of predetermined magnitude.

3. The vehicle seat as claimed in claim 2 , wherein the crash locking unit is operative so that the locking, which is provided by the crash locking unit in response to the crash of predetermined magnitude, occurs in a positively controlled manner at least partially in response to a change in geometry of the multi-bar linkage from the four-bar linkage to the five-bar linkage.

4. The vehicle seat as claimed in claim 3 , wherein the change in geometry of the multi-bar linkage comprises:

the opening of the second locking unit after the limit force is exceeded in response to the crash of predetermined magnitude, so that relative movement can occur between the two adjacent link mechanisms.

5. The vehicle seat as claimed in claim 2 , wherein:

the crash locking unit includes a latch and a mating element,

the crash locking unit is operative so that the locking, which is provided by the crash locking unit in response to the crash of predetermined magnitude, includes the latch and the mating element being engaged to one another,

the latch is effective in two directions,

the latch is pivotably mounted on one of the frame and the rocker, and

the mating element is fixedly attached to the other of the frame and the rocker.

6. The vehicle seat as claimed in claim 2 , wherein the multi-bar linkage becoming effective as a five-bar linkage comprises:

the opening of the second locking unit after the limit force is exceeded in response to the crash of predetermined magnitude, so that relative movement can occur between the two adjacent link mechanisms.

7. The vehicle seat as claimed in claim 1 , wherein the crash locking unit is operative so that the locking, which is provided by the crash locking unit in response to the crash of predetermined magnitude, occurs in a positively controlled manner at least partially in response to a change in geometry of the multi-bar linkage.

8. The vehicle seat as claimed in claim 7 , wherein the change in geometry of the multi-bar linkage takes place reversibly.

9. The vehicle seat as claimed in claim 8 , wherein the change in geometry of the multi-bar linkage comprises:

relative movement between the two adjacent link mechanisms, wherein the relative movement between the two adjacent link mechanisms is at least partially in response to the opening of the second locking unit.

10. The vehicle seat as claimed in claim 7 , wherein the change in geometry of the multi-bar linkage comprises:

relative movement between the two adjacent link mechanisms, wherein the relative movement between the two adjacent link mechanisms is at least partially in response to the opening of the second locking unit.

11. The vehicle seat as claimed in claim 1 , wherein:

the crash locking unit includes a latch and a mating element,

the crash locking unit is operative so that the locking, which is provided by the crash locking unit in response to the crash of predetermined magnitude, includes the latch and the mating element being engaged to one another,

the latch is effective in two directions,

the latch is pivotably mounted on one of the frame and the rocker, and

mating element is fixedly attached to the other of the frame and the rocker.

12. The vehicle seat as claimed in claim 11 , wherein the latch is coupled to the link mechanism positioned between the frame and the rocker.

13. The vehicle seat as claimed in claim 11 , wherein the latch is coupled, by way of a slot and a pin, to the link mechanism positioned between the frame and the rocker.

14. The vehicle seat as claimed in claim 1 , wherein at least one of the locking bar and the counterpart has two different functional surfaces which define different parameters for two opposite directions in which the crash of predetermined magnitude can occur.

15. The vehicle seat as claimed in claim 1 , further comprising a lower seat rail, wherein the frame is an upper seat rail that is cooperative with the lower seat rail to provide a longitudinal adjuster for the vehicle seat.

16. A vehicle seat for being mounted to a vehicle structure, and for operating advantageously in the event of a crash of predetermined magnitude, the vehicle seat comprising:

at least one multi-bar linkage, wherein the multi-bar linkage includes at least four link mechanisms, wherein prior to the crash of predetermined magnitude the multi-bar linkage is effective as a four-bar linkage for setting the seat's height, and wherein the at least four link mechanisms includes at least

(a) a frame for being fixed with respect to the vehicle structure,

(b) a rocker, and

(c) a link mechanism positioned between the frame and the rocker;

a crash locking unit for locking at least the frame and the rocker to one another in the event of the crash of predetermined magnitude; and

a second locking unit, wherein

for two adjacent link mechanisms of the at least four link mechanisms, the second locking unit provides a frictional interaction by way of which the second locking unit rigidly connects the two adjacent link mechanisms together prior to the crash of predetermined magnitude, whereby the multi-bar linkage is effective as the four-bar linkage prior to the crash of predetermined magnitude,

the second locking unit is operative for opening after a limit force is exceeded in response to the crash of predetermined magnitude, for allowing relative movement between the two adjacent link mechanisms, whereby the multi-bar linkage is at least temporarily effective as a five-bar linkage in response to the crash of predetermined magnitude; and

the crash locking unit is operative so that the locking, which is provided by the crash locking unit in response to the crash of predetermined magnitude, is provided at least partially as a result of the multi-bar linkage becoming effective as the five-bar linkage in response to the crash of predetermined magnitude, and

the second locking unit includes

(a) a locking bar pivotably mounted on a first of the two adjacent link mechanisms,

(b) a counterpart on a second of the two adjacent link mechanisms, and

(c) a spring between the locking bar and the first of the two adjacent link mechanisms.

17. The vehicle seat as claimed in claim 16 , wherein:

the crash locking unit includes a latch and a mating element,

the crash locking unit is operative so that the locking, which is provided by the crash locking unit in response to the crash of predetermined magnitude, includes the latch and the mating element being engaged to one another,

the latch is effective in two directions,

the latch is pivotably mounted on one of the frame and the rocker,

the mating element is fixedly attached to the other of the frame and the rocker, and

the latch is coupled to the link mechanism positioned between the frame and the rocker.

18. The vehicle seat as claimed in claim 16 , wherein the two adjacent link mechanisms are the rocker and the link mechanism positioned between the frame and the rocker.

19. The vehicle seat as claimed in claim 18 , wherein:

the crash locking unit includes a latch and a mating element,

the crash locking unit is operative so that the locking, which is provided by the crash locking unit in response to the crash of predetermined magnitude, includes the latch and the mating element being engaged to one another,

the latch is effective in two directions,

the latch is pivotably mounted on one of the frame and the rocker,

the mating element is fixedly attached to the other of the frame and the rocker, and

the latch is coupled to the link mechanism positioned between the frame and the rocker.

20. The vehicle seat as claimed in claim 16 , wherein at least one of the locking bar and the counterpart has two different functional surfaces which define different parameters for two opposite directions in which the crash of predetermined magnitude can occur.