A longitudinal adjuster for a vehicle seat, has a pair of seat rails, with a first seat rail which is fixed on the structure, a second seat rail which is guided in said first seat rail and is connected to the vehicle seat, and a releasable locking device with at least one latching plate for releasably locking the position of the first seat rail in relation to the second seat rail. A four-bar linkage, which interacts with the latching plate or the latching plates in order to unlock the longitudinal adjuster, is provided within the second seat rail.
1. A longitudinal adjuster for a vehicle seat, comprising:
a seat rail pair, having a first seat rail fixed to a structure, a second seat rail which is guided in that first seat rail and which is connected to the vehicle seat, and a releasable locking device having at least one catch plate for releasably locking the position of the first seat rail relative to the second seat rail,
wherein a four-bar linkage, which cooperates with the at least one catch plate in order to unlock the longitudinal adjuster, is provided within the second seat rail,
wherein the four-bar linkage is in the form of a parallelogram, wherein one side is secured to a rail in relation to the second seat rail and a side parallel therewith cooperates with the at least one catch plate.
2. The longitudinal adjuster as claimed in claim 1 , wherein the four-bar linkage has two coupling elements which are secured to a rail at one end and a stop which is arranged at the other ends of the coupling elements and which is movable at least in a longitudinal seat direction relative to the at least one catch plate.
3. The longitudinal adjuster as claimed in claim 2 , wherein the stop cooperates with the at least one catch plate in order to release the locking device and presses the at least one catch plate out of engagement with the first seat rail from a side of the second seat rail.
4. The longitudinal adjuster as claimed in claim 1 , wherein the actuation of the four-bar linkage is carried out via a gear connection which has an actuation region having an outer tooth arrangement and two elongate holes having tooth arrangements arranged at opposite sides, and the tooth arrangements are in engagement with the outer tooth arrangement of the actuation region.
5. The longitudinal adjuster as claimed in claim 1 , wherein the four-bar linkage has a base carrier which is securely fitted to the second seat rail, two coupling elements which are pivotably connected to the base carrier and a stop which is also connected pivotably to the coupling elements, wherein the stop is pretensioned by tension springs from below against the base carrier.
6. The longitudinal adjuster as claimed in claim 1 , wherein the longitudinal adjuster has a memory device which is activated by a second actuation device when the locking device is unlocked.
7. The longitudinal adjuster as claimed in claim 6 , wherein a rotational movement which is transmitted coaxially relative to an axis of rotation through a drive element is used for activating the memory device, wherein the drive element brings about actuation of the four-bar linkage.
8. The longitudinal adjuster as claimed in claim 6 , wherein the second actuation device for the memory device cooperates with a signal lever which cooperates with a shaft supported in a drive element and a memory activation lever.
9. A vehicle seat having at least one longitudinal adjuster as claimed in claim 1 .