DE10041528A1 - Car seat has head rest mounted on back rest which has fixed rear section and pivoted front section whose slope is adjusted by Bowden cable system, signal being sent which swivels it large angle in event of crash - Google Patents

Abstract

The car seat has a head rest (7) mounted on the back rest (3). This has a fixed rear section (9 ) and a front section (13) mounted on a pivot (15) at its upper end. The slope of this can be adjusted by a Bowden cable system (17, 21) in response to a signal and, in the event of a crash, a signal is sent which swivels through a large angle.

Description

The invention relates to a vehicle seat according to the Oberbe handle of claim 1.

Passive safety has been increasing for decades in the construction of motor vehicles, especially personal commercial vehicle, great attention paid. Besides efforts to optimize the entire vehicle structure for improvement The crash behavior by means of CAD techniques Measures to increase occupant safety in the interior Foreground. One result of this development is complex and quite effective restraint systems with different like airbags and belt tensioners.

Another, albeit less noticeable in public The result of the efforts to find one related to the occupants Safety-optimized interior design are solutions for Optimization of the position of parts of the seat structure, especially the headrest part, in a front or Rear impact. A practical solution to this Art provides the "Pro-Tech" system according to EP 0 627 340 A1 represents.

In the conventional system, this is the case in a rear impact Headrest part swiveled towards the driver's head in order to counter the dreaded "Whiplash" (whiplash).  

The headrest adjustment is there via a through the body pressure plate applied to the driver in the backrest a complicated and expensive lever mechanism causes.

Headrests, at least the front seats, are high adjustable to differentiate vehicle occupants body size an optimally positioned plant bie area for the back of the head in the event of a front impact In addition, the height adjustability also represents a comm element, because many drivers also prefer the normal driving a posture to the headrest ajar back of the head. For high-priced cars are in recently also electrically height-adjustable headrests offered.

Cars of the upper class and upper middle class have in in recent years - at least as an optional extra - too Headrests with adjustable inclination established. This he bring a further improvement in the adjustability of the Headrest on the anatomy and preferred posture of the Vehicle occupants. The inclination is adjusted at the be knew arrangements manually.

Overall, vehicle seats with height and incline ver adjustable headrests - especially those with electric Height adjustment - a complex construction and are therefore expensive, without already having all security requirements and comfort requirements. In particular is an inclination adjustment while driving - if at all - only possible in a cumbersome way.

The invention is therefore based on the object visually ver the function and construction of the headrest  to specify improved vehicle seat, which is characterized by a simple Chen construction with reliable function and simple operation availability.

This task is accomplished by a vehicle seat with the features of claim 1 solved.

The invention includes the basic idea, one known as such two-part headrest with a swivel baren front part with a suitable drive device for To swing forward in the event of a vehicle collision see and a vehicle seat with this combined arrangement equipment. Furthermore, it closes the essential Thoughts a non-manual tilt adjustment in expediently based on the two-part head support structure. Such a headrest net to equip with a motor or hydraulic rule drive device especially because the rigid head support rear part in a favorable manner a support surface not only for the actual adjustment, but also for Actuation of the headrest front part (and thus the Drive) with a high impulse due to a vehicle opening bulging offers.

In a constructively particularly meaningful implementation leadership is a mechanical actuator or control signal generator provided that the a vehicle occupant in the vehicle Impact given acceleration and from this the steering ersignal or at the same time the driving force for driving the Headrest front section. In the simplest case it points this mechanical encoder is arranged in the backrest and against an essentially rigid backrest frame  men with a movement component movable in the direction of travel Pressure plate on.

A currently preferred version closes but the realization that it can be used as a "drive source" Body of the vehicle occupant, which is a Be experiences acceleration and a force on the vehicle seat, especially the backrest, exercises the backrest applied a great force, but only one in it can cover a relatively small distance. This is because of it conditional on the space utilization in modern motor vehicles even without the backrest that is not absolutely necessary depths is optimized. Most of the depth or thickness of a backrest must for movements of the Vehicle occupants in the upholstery with low pressure - So to ensure adequate seating comfort - be available.

From this knowledge follows the further one, for the before drafted execution of the invention essential idea of the Vorse hens a drive or power transmission device for Crash adjustment resulting from the displacement of the vehicle sat with a short distance (at the expense of ultimately possible driving force) gains an increased adjustment range. Ultimately, the preferred embodiment closes the thought one, this basic idea through the interaction of to realize primary and secondary tension elements that by moving a moving body (in the concrete case of the body of the vehicle occupant) the, the aforementioned extension of the adjustment path by a zigzag or meandering deformation of the secondary Tension element is obtained by means of the primary tension elements.  

In a concrete embodiment, the primary Zugele elements as transverse or oblique to the direction of displacement of the Vehicle occupants as well as to the longitudinal axis of the secondary train mentally running, essentially inextensible wires or Threads or ribbons. In particular, the one another essential vertical arrangement of the direction of displacement the body of the vehicle occupant, the longitudinal axis of the secondary ren tension element and the longitudinal extension of the primary train elements ensures optimal force-displacement implementation thus advantageous functions of the drive device.

In a first embodiment, this is generally preferred th version wrap around as the primary tension elements the secondary tension element and are with both ends on the body - especially on the vehicle seat frame - attached. Both ends are attached there with either close to each other or from mutually more spaced points of the base body. In An alternative embodiment is the wires or Straps attached to the base body with one end each have a hook or eyelet at the free end with which or with which they encompass the secondary tension element.

Both versions can guarantee an movement of the vehicle occupant in the seat upholstery a certain game between the respective points of attack the primary tension elements and the secondary tension element are pre-selected to be seen. Another variant is a corresponding one Game but also with regard to the adjustment effect of the secondary Traction element itself provided, and the primary traction elements loop around or grasp the secondary tension element in the we considerable play-free.  

In another execution the realization of the primary Tension elements as wires or strips are these on their first Fixed end with the body and fixed at its second end connected to the secondary tension member, being with this in particular welded, (hard) soldered or pressed. The secondary tension element is also preferred as essentially chen inextensible wire or thread or inextensible tape formed, with a pronounced for the secondary tension element Flexibility for sufficiently easy formation of the zigzag or meander configuration must be provided in the event of a trigger. A shell-core configuration of the type is also advantageous a Bowden cable, which with suitable coordination of the compo can work particularly smoothly.

In a particularly simple and inexpensive way to implement guides are the primary pulling elements and / or the sekun dare tensile element as metal wires, especially steel wires, Metal bands (especially steel bands) or threads or bands made of high tensile fibers (Kevlar or similar) plastic.

In an alternative embodiment, the primary gels are elements instead of a multitude of individual wires, threads or Hinges realized by at least two surface tension elements, one on each side of the secondary train tes arranged and on the corresponding side of the basic body pers (specially the vehicle seat frame) is attached. This area Chen tensile elements are then each on a variety of Points attached to or grasped on the secondary tension element this with suitable hook or loop-shaped extensions or the like at a variety of points.  

The points of attack on the secondary tension element are - just like when executed with a large number of individual, essentially Chen linear tension elements - arranged so that the primary Surface tension elements on both sides of the secondary tension element in its longitudinal direction alternately attack this to the desired zigzag or meandering deformation in the release to realize state of the art. In an easy to manufacture, light and particularly advantageous in a vehicle back The integrable version is the mentioned surface Traction elements as essentially inextensible grids, braids or fabric, especially made of metal or fiber reinforced Plastic wires or threads or tapes formed.

The primary traction elements are in all of the versions mentioned expediently on the opposite Side bolsters of the vehicle seat attached. The primary train elements run as wires, threads or So tapes are preferably substantially horizontal, i.e. H. parallel to the vehicle floor. The secondary tension element is preferably on a cross member in a lower or upper end of the backrest or a cross member of the Seat part of the vehicle seat attached and thus runs in an angle approximately corresponding to the backrest angle of about 90 ° or less from the vehicle floor.

In addition or as an alternative to this, it is expedient before seen that the primary train elements and the secondary train element behind the backrest upholstery of the vehicle seat are arranged.

As an alternative to the mechanical control signal transmitter mentioned or actuator is used to control the drive device for the headrest front part an electronic control signal  Above usable, the quick approach of another Vehicle or an approach of the vehicle occupants the backrest of your own vehicle.

This control signal generator is with evaluation or processing processing devices for evaluating the approach signal equipped and given under predetermined distance-time criteria if these criteria are met, an upcoming or also (in the case of the evaluation of the approach of the vehicle sat on the backrest) already crashed vehicle characteristic control signal. The sensor is special a proximity sensor based on ultrasound or radar, like him is known per se to the expert.

The drive device for crash adjustment has one simple and reliable effective execution with the Headrest front part connected energy storage, esp especially one against the backrest or the head restraint rear supported and opposite the front headrest prestressed compression spring device. This lift mechanism is controllable or releasable by the control signal mentioned. When running as a compression spring device, he is particularly impressed in particular a release actuated via the control signal element assigned that the compression spring for swinging forward ken of the headrest front part releases.

Furthermore, the drive device, specifically the one mentioned Lift mechanism, expediently a locking device and / or a damping device associated with the Zu retreat of the headrest front part under the pressure of the impacting head of the vehicle occupant immediately after Prevents swiveling forward or at least significantly sword. This ensures that the head of the drive  witness inmates reliably intercepted and the dreaded Whiplash caused by overstretching the cervical spine can be prevented.

The use of a damper is physiologically advantageous here tion device that allows the retraction of the head restraint not completely prevented, but dampens significantly or delayed, and thus the impact of the impact The back of the head on the headrest. Preferably points this damping device a - known as such - hydraulic or friction attenuator.

In a preferred embodiment is for tilt adjustment connected to an electric motor on the front of the head restraint denes active actuator - especially a Bowden traction device as traction element - attached. In addition, between the headrest front and the headrest rear part of a passive Druckfe supported against the latter derelement provided which the headrest front part forward (i.e. towards the back of the head of the Vehicle occupants).

These components interact in an advantageous manner that a precisely predictable tightening of the tension element (for example by winding up the Bowden cable wire a role rigidly connected to the shaft of the electric motor or disc) the headrest front part by one metered angular amount pivoted about the axis of rotation, wherein this then by the force of the compression spring element in this Angular position is maintained. In simple and The compression spring element has an inexpensive design at least one steel coil spring; alternative Realizations exist in spiral springs, elastomer blocks or the like.  

An alternative to the aforementioned implementation of the Inclination adjustment includes a front part of the headrest orderly active pressure element with which the headrest front derteil in a desired angular position relative to the rear part brought and locked in this position. Particularly suitable net is a self-locking drive; alternatively can a drive without its own self-locking effect also a sepa rate locking device can be assigned.

Preferred designs of the active pressure element are one Rack and pinion device, in which the pinion in particular on the shaft of the electro serving as the drive source motor sits, or the piston rod or a similar movement Lich element of a piston-cylinder device. The last one rer is expediently indirectly via a hydraulic pump driven by an electric motor and can be completely or at least partially between the headrest rear and the head prop front part be arranged.

In view of the general trend of using separate Servomotors for various adjustment functions in the Automobile construction, this last-mentioned variant is rather Son be reserved for applications.

The drive device for tilt adjustment is either a simple actuation switch or - preferably - one assigned electronic control unit, which in particular a tilt angle memory for storing a plurality predetermined angular positions of the headrest front part having. With this version different drivers can Your optimal, pre-stored angular position at the push of a button recall.  

In a preferred embodiment, in addition to the inclination ver position a motorized or hydraulic height adjustment the headrest is provided. For height adjustment is in Usually there is a separate drive.

The drive device for the inclination adjustment can be put together with the headrest adjustable in height or alternatively on Backrest frame can be arranged in a fixed position. The former Variant is particularly useful when executing the An drive device with a rack and pinion arrangement, while the latter version in conjunction with a bow pulling device makes sense.

When designing the vehicle seat with a combined height and tilt adjustment is preferably a combined elek tronic control unit provided for both adjustment processes hen. This has in particular a vertical position memory for storing a predetermined number of altitude settings on the one with the inclination angle memory for the Nei power adjustment is coherent or at least least interacts with it in such a way that in the tax a plurality of angular positions and height positions can be saved together and in combination at the push of a button is available.

Advantages and advantages of the invention result in others from the subclaims and the following Description of preferred embodiments using the Characters. Of these show:

Fig. 1 and 1a is a drawing for explaining the structure and grundsätzli chen a variant of the operating power supply to the crash adjustment and tilt adjustment of the headrest in an inventive on-vehicle seat,

Fig. 2 is a schematic perspective view of a car front seat according to a first embodiment of the crash release and

Fig. 3 is a schematic perspective view of a car front seat according to a second embodiment.

In Fig. 1 are shown roughly schematically in the manner of a cross-sectional representation of the upper portion of the backrest of a car seat 1, the components essential for understanding an embodiment of the invention. The car seat 1 includes the backrest 3 with approximately vertically aligned headrest guides 5 for holding a headrest 7th This consists essentially of a headrest rear part 9 , which is fixed with headrest rods 11 ? is connected to the vertically displaceable mounting in the headrest guides 5 of the backrest 3 , and a headrest front part 13 movable relative to the headrest rear part 9 .

The headrest front part 13 is pivotable about a horizontal axis of rotation 15 at the upper, forward-bent end of the headrest rear part 9 , with its lower end effectively in the direction of arrow x towards the back of a vehicle occupant (not shown) or away from it is movable. In the figure, a first rotational position of the headrest zen front part 13 is drawn through and a second rotational position is shown in dashed lines.

Between the headrest rear part 9 and the headrest front part 13 , a spreading lever arrangement 17 which fixes the front part relative to the rear part is provided. This is assigned a spring element 18 , which gives the spreading levers and thus the front headrest part 13 a bias against the rear part 9 . A Bowden cable 19 is attached at one end to an articulation point 17 a of the spreading lever arrangement 17 .

The Bowden cable 19 branches in a coupling element 20 , which is shown in more detail in FIG. 1a, in a first and second Bowden cable branches 19.1 and 19.2 . As can be seen in Fig. 1a, the coupling element 20 comprises in essence Chen a wire connector 20 a, which connects the ends of the inner wires of the one-piece Bowden cable section 19 and the two branches 19.1 and 19.2 so firmly that - in the manner of an OR gate - A tensile force acting on one of the branches 19.1 , 19.2 is passed on to the one-piece section 19 .

A first end of the Bowden cable (more precisely: an inner wire) is wound around a roller 21 a, which sits on the shaft of an electric motor 21 to adjust the inclination. The electric motor is controlled - which is not shown in the figure - by an actuation switch or by an electronic control unit. The second end of the Bowden cable (which is not shown in FIG. 1, however) is connected to a drive for crash triggering, which is described in more detail below with the aid of examples.

When controlling the electric motor via a corresponding control signal ( "headrest forward" or "head rest to the back"), the roller 21a is rotated in one of the two symbolized by the arrow directions of rotation and the inner wire of the Bowden cable 19 tightened or relaxed, whereupon the head prop front part 13 is moved forward or backward via the spreading lever arrangement 17 in cooperation with the spring element 18 relative to the head prop rear part. In a fundamentally similar manner, the drive force applied in the event of a crash triggering is transmitted to the front part of the head restraint, but in this case the force transmission takes place very quickly, and the spreading lever arrangement is shown in dashed lines in FIG. Position stretched.

In this position the lever arrangement is self-locking, can thus when the rear of the vehicle occupant hits the head do not revert to their originally set position and safely catches the head. After the Accident in a suitable (known) way manually unlocked and can then in the set Nei position can be reduced.

It should be noted that the spring element 18 must have such a constant spring that the set angular position of the front headrest part is maintained even when the rear of the vehicle occupant is violently applied.

Fig. 2 shows a dashed perspective view's rule a car front seat 100 with a seat part 101 , a backrest 103 and a headrest 105 , in which a drive device 107 is installed for a (not shown) adjustment mechanism with which the headrest 105 in In case of a rear and optionally also frontal crash can be adjusted ver. The seat part 101 and the backrest 103 have separate frame parts 109 and 111 made of metal profiles.

The headrest 105 has the structure described above, of which the headrest rear part 105A , the horizontal axis of rotation 105B and the pivotable headrest front part 105C can be seen in this figure.

The drive device 107 comprises, for example, a total of five steel wires 113 , each of which is fastened at one end to one of the upright sections of the frame part 111 of the backrest 103 and has a hook 113 a at the other end. The steel wires 113 run essentially horizontally and transversely to the longitudinal axis of the vehicle and thus to the direction of movement of a vehicle occupant (not shown) in the event of a rear-end collision, and alternately embrace with their hooks 113 a from both sides an essentially vertical Bowden cable 115 .

The Bowden cable 115 is attached at one end to a lower cross member 117 of the frame part 111 , and its upper end is - which is not shown in the figure - with the headrest front part 105 C or a lever-joint assigned to it. Mechanism connected. The steel wires 113 and the Bowden cable 115 are each movably embedded over the greater part of their longitudinal extent in a load distribution plate 119 , which in particular also covers the points of engagement of the hooks 113a with the Bowden cable 115 with respect to the body of the vehicle occupant mentioned.

If in a sufficiently strong rear impact or "rebound" after a front impact, the body of the vehicle was seated with an acceleration exceeding the absorption capacity of the (not shown) upholstery from the front against the backrest 103 , then it is particularly pressed against the steel wires 113 , and these pull at the respective point of engagement of the hook 113 a with the Bowden cable 115 towards them, since they themselves are inextensible.

The flexible Bowden cable 115 takes on a zigzag or meandering shape due to the tension exerted alternately from both sides by the steel wires 113 . Its (upper) free end is thereby pulled down by an amount that substantially exceeds the amount of displacement of the vehicle occupant in the direction of the backrest in the direction of the arrow in the figure and triggers a pivoting movement of the headrest front part, which, for. B. can be driven by a Bowden cable released compression spring device between the head restraint rear part and the head restraint front part.

FIG. 3 shows a further drive device 207 in a front passenger seat 200 which corresponds to the seat according to FIG. 2 in terms of its other structure. The drive device 207 comprises a total of six fiber reinforced, z. B. kevlar-reinforced plastic tapes 213 , which are alternately looped from both sides around a element serving as a secondary train, also fiber-reinforced plastic cable 215 and each with two ends in the slots of the upright portions of the frame part 211 are attached.

The function of this arrangement basically corresponds fully to that of the first embodiment. The plastic tapes 213 and the plastic cable 215 interact in a similarly frictionless manner together as the wires according to FIG. 2 with the Bowden train provided there as a secondary tension element. The flat design of the primary tension elements as nets or strips according to FIGS. 2 and 3 compared to steel wires enables the omission of a separate load distribution element in these latter embodiments.

The implementation of the invention is not described above limited versions, but also in a lot number of modifications possible, which in the context of professional Han lying there.

LIST OF REFERENCE NUMBERS

1

;

100

;

200

Vehicle seat (front seat)

3

;

103

;

203

backrest

5

Head restraint guide

7

;

105

;

205

headrest

9

;

105

A;

205

A headrest rear

11

Headrest rod

13

;

105

C;

205

C front headrest

15

;

105

B;

205

B axis of rotation

17

Spreizhebelanordnung

17

a pivot point

18

spring element

19

Bowden

19.1

.

19.2

Bowden branch

20

coupling element

20

a wire connector

101

;

201

seat part

107

;

207

driving means

109

.

111

;

209

.

211

frame part

113

steel wire

113

a hook

115

Bowden

117

;

217

crossbeam

119

Load distribution plate

213

Plastic tape

215

Plastic cable

Claims (30)

1. Vehicle seat ( 1 ; 100 ; 200 ), in particular for a passenger car, with a backrest ( 3 ; 103 ; 203 ) and a headrest ( 7 ; 105 ; 205 ) arranged at the upper end thereof, which is essentially rigid in the The backrest of the headrest rear part ( 9 ; 105 A; 205 A) and a headrest front part ( 13 ; 105 ; 105 B) about a substantially horizontal axis of rotation ( 15 ; 105 B; 205 B), in particular at the upper end of the headrest rear part. 105 C; 205 C), characterized by at least one drive device ( 17 , 19 , 21 ; 107 ; 207 ) for swiveling the headrest front part forward about the axis of rotation by a large angular amount in response to a characteristic of a vehicle impact stes control signal and by adjustable angular amounts in response to a desired headrest inclination characterizing second control signal for the inclination adjustment. 2. Vehicle seat according to claim 1, characterized in that the drive device comprises an at least indirectly acting on the headrest front element, in particular a Bowden cable device ( 19 ; 115 ), as a force transmission element. 3. Vehicle seat according to claim 1 or 2, characterized in that the drive device comprises an electric motor ( 21 ) as the first drive element for tilt adjustment. 4. Vehicle seat according to claim 3, characterized, that the electric motor also pivots forward caused a vehicle impact. 5. Vehicle seat according to claim 4, marked by an electronic control that drives the electric motor first signaling device, the approach of another vehicle ges and / or the approach of the vehicle occupant to the Backrest detected and under predetermined path-time cri terien evaluates and when they are fulfilled a be characterizes the preceding or previous vehicle impact outputs the second control signal. 6. Vehicle seat according to one of claims 1 to 3, characterized by a mechanical actuator ( 113 ; 213 ) or signal generator for the first control signal, which detects the acceleration given to the vehicle occupant during the vehicle impact and into a driving force for the drive device to the front - Swiveling when the vehicle crashes. 7. Vehicle seat according to one of claims 2 to 6, characterized in that the force transmission element ( 19 ) on a between the headrest rear part ( 9 ) and the headrest front part ( 13 ) arranged, in particular spring-loaded, spreading lever device ( 17 ) acts in this way That the transmission of a tensile force causes the headrest front part to spread away relative to the headrest rear part about the axis of rotation ( 15 ). 8. Vehicle seat according to claim 7, characterized in that the spreading lever device ( 17 ) has a locking device for locking in the spread position, in particular in an over-dead center position. 9. Vehicle seat according to claim 2 and one of claims 6 to 8, characterized in that the pulling element ( 19 ) has a connection or branching point ( 20 ) on which on the one hand a drive element for tilt adjustment and on the other hand a drive element for follow-up Swivels forward in the event of a vehicle impact. 10. A vehicle seat according to claim 9, characterized in that a coupling element ( 20 ) for the fixed connection of the Bowden cable ( 19 ) with two pull wires ( 19.1 ; 19.2 ) is provided at the connection or branching point. 11. Vehicle seat according to one of the preceding claims, characterized, that on the headrest front part with an electric motor connected active tension element, in particular a bow pulling device, attached and between the headrest zen rear section and the headrest front section against the headrest buttock and that Passive head restraint front part forward Compression spring element is arranged. 12. Vehicle seat according to claim 11, characterized, that the passive compression spring element is a steel screw feather. 13. Vehicle seat according to one of claims 1 to 10, characterized, that on the headrest front part an at least indirectly active associated with an electric motor, in particular self-locking, pressure element is attached. 14. Vehicle seat according to claim 13, characterized, that the active pressure element as a rack a zwi between the headrest rear and the headrest Front part arranged rack and pinion device is trained. 15. Vehicle seat according to claim 13, characterized, that the active pressure element as a piston rod a zwi between the headrest rear and the headrest Front part arranged piston-cylinder device from  is formed, which is indirectly via a hydraulic pump is driven by an electric motor. 16. Vehicle seat according to one of the preceding claims, marked by one with a control signal input of the drive unit connected electronic control unit, esp special a tilt angle memory for storage a plurality of predetermined angular positions of the head props front part around the axis of rotation, for off giving the second control signal. 17. Vehicle seat according to one of the preceding claims, marked by a motor or hydraulic drive device for height adjustment of the headrest. 18. Vehicle seat according to claim 16 and 17, characterized, that the electronic control unit has a vertical position tion memory for storing a predetermined number of height settings of the headrest, which especially related to the inclination angle memory is formed or cooperates in such a way that in the control unit has a plurality of angular positions / Height position value pairs for adjusting the headrest is storable. 19. Vehicle seat according to one of the preceding claims, characterized, that the drive device for forward pivoting together with the headrest, especially by means of  a drive for height adjustment, height adjustable is. 20. Vehicle seat according to one of claims 6 to 19, characterized, that the mechanical actuator or control signal generator for the first control signal is arranged in the backrest nete and against an essentially rigid frame the backrest with a movement component parallel has movable pressure plate to the direction of travel. 21. Vehicle seat according to one of claims 6 to 19, characterized in
that the mechanical actuator a plurality of primary tension elements ( 113 ; 213 ), each having at least one end attached to a backrest frame ( 109 , 111 ; 209 , 211 ) and in the displacement area of the vehicle are arranged, and
has a secondary, elongated tension element ( 115 ; 215 ) which is connected to the backrest frame with at least one end and at least at one point to the headrest front part ( 105 C; 205 C) or the associated drive device and runs in the longitudinal direction thereof attack the primary tension elements in a substantially alternating manner from opposite sides such that it is deformed in a zigzag or meandering manner when the primary tension elements are displaced by a displacement of the vehicle occupant and thereby drives the headrest front part or controls its drive device. 22. Vehicle seat according to claim 21, characterized in that the primary tension elements ( 113 ; 213 ) as transverse or oblique to the direction of displacement of the vehicle occupant and transverse or oblique to the longitudinal axis of the secondary tension element, substantially inextensible wires or bands are formed, which in particular the loop around the secondary tension element ( 115 ; 215 ) and are attached to the backrest frame with both ends or are attached to the backrest frame ( 109 , 111 ; 209 , 211 ) with one end each and have a hook or an eyelet at the free end with which the they embrace the secondary tension element or which are attached at one end to the backrest frame and are firmly connected with their free end to the secondary tension element. 23. Vehicle seat according to claim 21 or 22, characterized in that the secondary tension element ( 115 ) is designed as an essentially inextensible, distinctly flexible wire or undehnba res, flexible band. 24. Vehicle seat according to claim 21 or 23, characterized, that the primary tension elements by at least one each one side of the secondary tension element and this encompassing at a plurality of points or attached to this at a plurality of points Surface tension element, especially as essentially inextensible grid, braid or fabric.   25. Vehicle seat according to one of claims 21 to 24, characterized in that the primary tension elements ( 113 ; 213 ) are alternately attached to the opposite side cheeks ( 111 ; 211 ) of the backrest frame and the secondary tension element ( 115 ; 215 ) on a cross member in a lower or upper end portion of the backrest or on a cross member of the seat part is attached. 26. Vehicle seat according to one of claims 21 to 25, characterized in that the primary tension elements ( 113 ; 213 ) and the secondary tension element ( 115 ; 215 ) are arranged behind a backrest pole of the vehicle seat. 27. Vehicle seat according to one of claims 21 to 26, characterized in that the primary traction elements ( 113 ) and the secondary traction element ( 115 ) in an at least their connection areas covering the vehicle occupant covering flat load distribution element ( 119 ), in particular a load distribution plate, movable are inserted. 28. Vehicle seat according to one of the preceding claims, characterized, that the drive means one with the headrest Front part connected and actuated by the control signal hit energy storage, especially one against the Backrest or the headrest rear part supported and pressure biased against the headrest front spring device.   29. Vehicle seat according to claim 28, characterized, that the energy storage a locking and / or Damping device is assigned, which the rejection chen of the headrest front immediately after Preventing panning forward or substantial difficult. 30. Vehicle seat according to claim 29, characterized, that the damping device is a hydraulic or Rei Exercise attenuator includes.