Adjusting device for a headrest of a vehicle seat and vehicle seat
The present disclosure relates to an adjusting device for a headrest of a vehicle seat, the adjusting device comprising: a backrest fastening for attaching to a backrest, a holding device with a vertical adjustment means for adjusting the headrest in vertical direction, a longitudinal adjusting means for adjusting the holding device in a longitudinal direction, the longitudinal adjusting means comprising a four-joint gear provided between the backrest fastening and the holding device, the four-joint gear comprising two guiding arms. Here, the longitudinal adjusting means comprises a spindle drive, the spindle drive being provided between the holding device and one of the guiding arms. The guiding arm is preferably a front guiding arm. A spindle of the spindle drive is preferably translationally displaceable and provided in an arc-shaped slot guiding of the guiding arm. Moreover, a vertical adjustment by a second spindle drive is provided.
1 . An adjusting device for a headrest of a vehicle seat, the adjusting device comprising:
a backrest fastening for attaching to a backrest,
a holding device with a vertical adjustment means for adjusting the headrest in vertical direction,
a longitudinal adjusting means for adjusting the holding device in a longitudinal direction, the longitudinal adjusting means comprising:
(1) a four-joint gear provided between the backrest fastening and the holding device, the four-joint gear comprising two guiding arms including a front guiding arm having a cam guiding, the cam guiding being an arc-shaped slot provided in the front-guiding arm, and
(2) a spindle drive provided between the holding device and the front guiding arm of the four-joint-gear, the spindle drive comprising a spindle motor received in or at the holding device, and a spindle shaft having a spindle head received within the cam guiding,
wherein the spindle shaft is translationally displaceable by the spindle motor.
2 . The adjusting device of claim 1 , wherein the spindle shaft of the longitudinal adjusting means is configured to be pulled and/or tensioned when the holding device is displaced in a longitudinal direction forwards.
3 . The adjusting device of claim 2 , wherein the spindle shaft is formed from a flexible material.
4 . The adjusting device of claim 1 , wherein the spindle head of the spindle shaft is further received in a guiding means provided in the holding device, for guiding the spindle head end during the longitudinal adjustment.
5 . The adjusting device of claim 4 , wherein the four-joint gear comprises two parallel front guiding arms and two parallel rear guiding arms, the spindle drive being attached to only one of the two front arms, and the guiding means being provided in both front arms, for synchronizing the left and right side of the four-joint gear during longitudinal displacement.
6 . The adjusting device of claim 4 , wherein the guiding means comprises a toothed wheel beared in the spindle head, the toothed wheel comprising a peripheral teeth formation extending on a complete or partial circumference of the toothed wheel and a guiding teeth formation being provided in the holding device, for receiving and meshing with the toothed wheel.
7 . The adjusting device of claim 6 , wherein the guiding means is formed as a window extending in the holding device in vertical direction.
8 . The adjusting device of claim 1 , wherein vertical adjustment device is motor-driven and provided between the headrest and the holding device.
9 . The adjusting device of claim 8 , wherein the motor-driven vertical adjusting device comprises a second spindle motor and a second spindle shaft being translationally displaceable by the second spindle motor.
10 . The adjusting device of claim 9 , wherein the second spindle motor is received at the holding device and wherein the second spindle shaft is connected to the headrest.
11 . The adjusting device of claim 9 , wherein the vertical adjusting device and the longitudinal adjusting means comprise an equal spindle motor, preferably with spindle shafts of different lengths.
12 . The adjusting device of claim 9 , wherein the spindle shaft of the longitudinal adjusting means and/or the second spindle shaft of the vertical adjusting device extend in vertical direction.
13 . The adjusting device of claim 1 , wherein the longitudinal adjusting means and the vertical adjusting device comprise a common interface at the holding device.
14 . The adjusting device of claim 1 , wherein the four-joint gear comprises:
at least one front guiding arm being pivotably connected to the backrest fastening in a lower front joint point, and being pivotably connected to the holding device in an upper front joint point, and
at least one rear guiding arm being pivotably connected to the backrest fastening in a back lower joint point and being pivotably connected to the holding device in an upper rear joint point,
the front guiding arm and the rear guiding arm being of different lengths.
15 . A vehicle seat, comprising
a backrest,
a headrest, and
an adjusting device according to claim 1 , the backrest fastening of the adjusting device being attached to the backrest and the headrest being vertically displaceable relative to the holding device and the backrest.