Patent Abstract:
A headrest arrangement for a vehicle seat consisting of a back and a bottom seating part. Said arrangement comprises a headrest part that is connected to the back of the seat, with the connection configured in such a way that the headrest part can be moved between an in-use position arranged above the back of the seat and corresponding to its headrest function and a non-use position wherein the headrest part can be releasably locked in both positions. The headrest part in non-use position and relative to the in-use position is lowered in the direction of the seating part and is arranged horizontally in the area of the front part of the back of the seat. The invention also relates to a vehicle seat fitted with said headrest arrangement.

Full Description:
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS 
   This application claims benefit to International Application No. PCT/EP02/06828 filed on Jun. 20, 2002, and published in the English language under PCT Article 21(2); German application no. DE20110342.7, filed Jun. 22, 2001, all of which are incorporated herein by these references. 
   BACKGROUND 
   The present invention relates to a head restraint arrangement for a vehicle seat comprising a backrest and a lower seat surface part, having a head-supporting part which is connected or can be connected to the backrest via retaining means. 
   The invention furthermore also relates to a vehicle seat fitted with a head restraint arrangement of this type, having a lower seat surface part and a backrest which can be folded over. 
   It is known to provide vehicle seats with head restraints which are intended to protect the seat user against accident-included injuries in the region of the cervical vertebrae, i.e. against “whiplash”. It has also been known from a long time to guide the head restraint on or in the backrest in a manner such that it can be adjusted in height via restraining means and such that it can be locked in different positions in order to adapt it to users of differing size. 
   In many cases, it is intended that vehicle seats can be changed between different positions to utilize the vehicle in a variable manner. In this case, because of the head restraint which is arranged protruding in the upper region, folding the backrest over in particular frequently causes problems in respect of possible collisions with other vehicle parts. Sometimes, the head restraint even has to be entirely removed before the backrest is folded over. 
   SUMMARY 
   The present invention is based on the object of providing a head restraint arrangement of the above-mentioned type and a seat fitted with said head restraint arrangement, with which a particularly easy change in the arrangement of the seat and its parts is possible. 
   According to the invention, this is achieved first of all in accordance with the claims by the fact that the retaining means are designed in such a manner that the head-supporting part can be transferred between an operative position, which is arranged in accordance with its head-supporting function above the backrest, and an inoperative position and is locked releasably in both positions, the head-supporting part, in the inoperative position, firstly being lowered relative to the operative position, in the direction of the seat surface part and, secondly, being arranged lying in the region of a backrest front side in front of the backrest. 
   A vehicle seat fitted with a novel head restraint arrangement of this type is distinguished in accordance with the claims by the fact that, starting from an operative position, which is suitable for sitting, the seat surface part can be folded over through approximately 180° about a transverse axis, which is arranged in its front region away from the backrest, in such a manner that it lies with its lower side, which points upward, in a plane with an adjacent loading floor of the vehicle, it being possible, in the inoperative position of the head-supporting part, for the backrest to be folded over through approximately 90° about a lower transverse axis in the direction of the seat surface part, and it then lying with its rear surface likewise approximately in the plane of the loading floor. In this case, it is expedient, firstly, for the backrest together with the head-supporting part situated locked in the inoperative position, to be accommodated, in the folded-over position of the backrest, and, secondly, for the lower seat surface part with its seat cushion in the inverted position to be accommodated in each case in a trough-like receptacle of the vehicle. 
   The invention makes a transfer between the operative and inoperative position very simple and comfortable; a complete removal of parts, such as, in particular, the head restraint, can be rendered superfluous, so that there is also no risk of any part being lost; on the contrary, all of the components are always available to the user in the vehicle for use in a variable manner. During the transfer of the backrest into the folded-over position of the backrest, the locking according to the invention of the head restraint part in its inoperative position, which is situated in front of the backrest, is of particularly advantageous importance because it reliably avoids uncontrolled oscillating movements and resultant problems when introducing or placing the head restraint part into the associated receiving trough of the vehicle without the head restraint part here having to be secured or guided awkwardly by hand. 
   Further advantageous design features and advantages of the invention achieved thereby are contained in the subclaims, which are dependent on claims and  33 , and in the following description. 

   
     DESCRIPTION OF DRAWINGS 
     The invention will be explained more precisely with reference to a preferred exemplary embodiment which is illustrated in the drawing, in which: 
       FIG. 1  shows a schematic, partially cutaway side view of a vehicle seat with a head restraint arrangement according to the invention, with different positions of the components being illustrated simultaneously, 
       FIG. 2  shows an enlarged view just of the head-supporting part, in a view corresponding to  FIG. 1 , 
       FIG. 3  shows a front view of the head-supporting part in the arrow direction III according to  FIG. 2  (likewise illustrated partially cut away and transparently), 
       FIG. 4  shows a schematic sectional view in the plane IV—IV according to  FIG. 3  in different positions of the head-supporting part during the transfer between its two positions, 
       FIG. 5  shows a section in the plane V—V according to  FIG. 3 , 
       FIG. 6  shows a view analogous to  FIG. 3  just of an inner supporting housing of the head-supporting part together with the upper region of a retaining-rod element, 
       FIG. 7  shows a section in the central plane VII—VII according to  FIG. 6 , 
       FIG. 8  shows a section in the plane VIII—VIII according to  FIG. 6 , 
       FIG. 9  shows a section in the plane IX—IX according to  FIG. 6 , 
       FIG. 10  shows a further section in the plane X—X according to  FIG. 6 , and 
       FIG. 11  shows a perspective exploded illustration of the functionality essential parts of the head restraint arrangement according to the invention. 
   

   DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
   In the various figures of the drawing, identical parts and components are always provided with the same reference numbers, and so they are generally also only described once in each case. 
     FIG. 1  illustrates a vehicle seat  2  which comprises a backrest  4  and a lower seat surface part  6  and has a head restraint arrangement  8  according to the invention. A head-supporting part  12  is connected or can be connected to the backrest  4  via retaining means  10 . 
   As can furthermore be gathered from  FIG. 1 , the retaining means  10  are designed in such a manner that the head-supporting part  12  can be transferred between an operative position A, which is arranged in accordance with its head-supporting function above the backrest  4 , and an inoperative position B and is locked releasably in both positions A, B. In the inoperative position B, the head-supporting part  12  is, firstly, lowered relative to the operative position A in the direction of the lower seat surface part  6  and, secondly, is arranged lying in the region of a backrest front side  14  in front of the backrest  4 . In this manner, the invention eliminates the projecting length, which is necessary in the operative position A, of the head-supporting part  12  protruding upward above the backrest  4  by, in the inoperative position B, no parts of the head-supporting part  12  protruding any more over the backrest  4 . 
   It is expedient for the invention if the retaining means  10  have a retaining-rod element  16  having two retaining rods  20 ,  22  which are parallel to each other and are guided in a longitudinally displaceable manner in guides  18  of the backrest  4  (which can only be seen in  FIG. 1 ). In addition, the retaining rods  20 ,  22 , which can be displaced in the guides  18 , can be locked in at least two, preferably, for the purpose of adjusting the height, in a plurality of, different positions. The retaining rods  20 ,  22  are connected to each other, in particular in one piece via a transverse web  24 , in their end region which is situated outside the backrest  4  and the guides  18 . The retaining rods  20 ,  22  are designed here such that they are curved “in the manner of a walking stick” in their upper end region in the transition to the transverse web  24  in such a manner that the transverse web  24  is arranged offset with respect to a guide plane  26 , which is defined by the two parallel retaining rods  20 ,  22  (see, in this respect,  FIGS. 2 and 4 , for example), in the direction of the backrest front side  14 . 
   The head-supporting part  12  is guided via a bearing arrangement  28  on the transverse web  24  of the retaining-rod element  16  in a manner such that it can be pivoted about an axis of rotation  30 , which is defined by the transverse web  24  or is identical with the longitudinal central axis of the transverse web  24 , and in a manner such that it can be locked in (at least) two different positions. In the preferred exemplary embodiment, the head-supporting part  12  can be pivoted through approximately 180° and can be locked alternatively in two positions, specifically either in a supporting position C extending upward approximately as an elongation of the retaining rods  20 ,  22  (see  FIGS. 2 and 4 ) or in a rest position D which, starting from the transverse web  24 , extends in an inverted manner downward approximately parallel to the retaining rods  20 ,  22  (see  FIG. 4  in this respect where the process of pivoting it over between the positions C and D is illustrated with reference to numerous intermediate positions). Furthermore, it is expedient, for the transfer of the head-supporting part  12  from the operative position A into its inoperative position B ( FIG. 1 ) if it is arranged with a central plane  34 , which runs approximately parallel to a front head-supporting surface  32  (see  FIG. 4 ), asymmetrically with respect to the axis of rotation  30  in such a manner that the pivoting between the supporting position C and the rest position D causes it to be offset in each case with respect to the axis of rotation  30 . In the supporting position C, the central plane  34  is situated, according to  FIG. 4 , behind the axis of rotation  30  and, in the rest position D, the central plane  34  is situated in front of the axis of rotation  30 . As a result, the head-supporting part  12  is positioned, as it is being lowered by pushing the retaining rods  20 ,  22  into the guides of the backrest  4 , in front of the backrest front side  14  of the backrest  4  (inoperative position B according to  FIG. 1 ). 
   The bearing arrangement  38  has a bearing part  36  which sits in a rotationally fixed manner, i.e. secured against rotation, on the transverse web  24  of the retaining-rod element  16  and on which an inner supporting housing  38  of the head-supporting part  12  is guided rotatably. As emerges from  FIG. 11 , the bearing part  36  is expediently composed of two halves  36   a  and  36   b  which are connected to each other enclosing the transverse web  24 . This can take place on one side by a form-fitting engagement of a retaining web  40  of the one bearing-part half  36   a  in a corresponding retaining opening  42  in the other bearing-part half  36   b , the two halves being connected on the other side, for example, by means of a rivet  44  or similar connecting element (in addition to  FIG. 11  also see  FIG. 8 ). For the bearing part  36  to sit in a rotationally secure manner on the transverse web  24 , form-fitting means are provided, in particular, for example, according to  FIG. 11 , at least one projecting lug  46  of the transverse web  24 , which engages in a corresponding holder within the bearing part  36  (also see  FIG. 8 ). The supporting housing  38  sits with inner bearing sections  47   a  rotatably on two lateral bearing sections  47   b  of the bearing part  36  ( FIG. 11 ). In this case, the supporting housing  38  comprises two housing parts  38   a  and  38   b  which are connected, for example screwed and/or latched, to each other enclosing the bearing part  36 . 
   A locking device  48  which interacts with the bearing part  36  and is intended for the supporting position and the rest position is provided within the supporting housing  38 . This locking device has a bolt slide  50  which is guided displaceably in the supporting housing  38  and uses at least one bolt element  52  to engage, either in the supporting position C or in the rest position D, in a respectively corresponding bolt opening  54  in the bearing part  36  (see in particular  FIG. 10  in this respect). As emerges, for example, from  FIGS. 5 ,  7  and  8 , the bolt slide  50  is guided in a slide holder  56  formed within the supporting housing  38 . the bolt slide  50  preferably has two laterally offset bolt elements  52 . Two bolt openings  54  are accordingly also provided in each case for the two positions C and D. The bolt slide  50  is acted upon here with a spring force F 1  in the direction of its locking position. According to  FIGS. 5 ,  7 ,  8  and  11 , a helical compression spring  58 , for example, is arranged for this purpose between the bolt slide  50  and the slide holder  56  of the supporting housing  38 . 
   The bolt slide  50  interacts with an actuating element  60  which is accessible from the outside for, preferably, manual actuation by pushing, in particular an actuating element in the manner of a push-button. This actuating element  50  is preferably arranged in a region of the head-supporting part  12  which, in the supporting position C, points downward in the direction of the backrest  4  and, in the rest position D, points upward in the opposite direction. This makes practical, very comfortable actuation possible. By means of the actuating element  60 , the bolt slide  50  can be displaced in the direction of a displacement axis or displacement plane  62  which, in the supporting position C, is arranged lying approximately parallel to the guide plane  26 , in the region situated between the guide plane  26  of the retaining rods  20 ,  22  and the axis of rotation  30 . Reference is made in this respect to  FIG. 2 , in particular. 
   It is furthermore advantageous if the head-supporting part  12  is acted upon with a rotational spring force F 2  in such a manner that—in each case after the lock is released—the pivoting in the one direction of rotation takes place counter to the rotational spring force F 2  by means of an external actuating force (in particular manually) which exceeds the latter and takes place in the other direction of rotation essentially automatically by means of the rotational spring force F 2 . In the preferred exemplary embodiment, the rotational spring force F 2  is directed in such a manner that, starting from the rest position D, the supporting position C is automatically reached by the spring force F 2  after the lock is released. However, an inverted variant is also included within the scope of the invention. As emerges from  FIGS. 9 and 11 , in order to produce the rotational spring force F 2 , a torsion spring  64  is provided which is designed, for example, as a coiled leg spring and is arranged supported coaxially with respect to the axis of rotation  30  between the head-supporting part  12  or the interior of the supporting housing  38 , on the one hand, and the retaining-rod element  16  or the bearing part  36 , on the other hand. 
   As furthermore emerges from  FIG. 1 , the head restraint arrangement  8  according to the invention is preferably designed for a vehicle seat  2  of this type which can likewise be transferred between an operative position, which is suitable for sitting, and an inoperative position. For transfer into the inoperative position, the seat surface part  6  can be folded over through approximately 180° in the arrow direction  68  about a transverse axis  66 , which is arranged in its front region away from the backrest  4 , in such a manner that it lies with its lower side  70 , which then points upward, approximately in a plane  72  with an adjacent loading floor of the vehicle. In addition, in the locked inoperative position B of the head-supporting part  12 , the backrest  4  can be folded over through approximately 90° in the arrow direction  76  about a lower transverse axis  74  in the direction of the seat surface part  6 , so that it then lies with its rear surface  78  likewise approximately in the plane  72  of the loading floor. This configuration enables the vehicle seat  2  to be used, in particular, as an additional seat, spare seat or child&#39;s seat, specifically, in particular, in an arrangement in the rear region of the vehicle, in which it is oriented rearward with respect to the actual direction of travel. The backrest  4 , with the head-supporting part  12  situated locked in the inoperative position B is accommodated, in the folded-over position of the backrest, in a trough-like receptacle of the vehicle. the same also applies for the seat surface part  6 , which, in its folded-over position with its upholstery downward, is situated in a floor trough. Both seat parts  4 ,  6  then use their rear or lower sides  70 ,  78  to supplement the loading area of the vehicle. 
   Owing to the limited structural space in the rear region of the vehicle, the backrest  4  of a spare seat of this type may be designed to be only relatively low or short. In the case of the dummy which is illustrated in  FIG. 1  of a female of the “5 th  percentile”, the backrest  4  reaches with its upper edge only approximately as far as the lower edges of the shoulder blades. The head restraint arrangement  8  according to the invention is therefore required in order to provide the occupant, in her sitting position which is turned rearward, with sufficient grip in the head and neck region during braking maneuvers. 
   The invention is not confined to the exemplary embodiments illustrated and described, but also encompasses all variants of equivalent effect within the meaning of the invention. Furthermore, the invention is also not yet confined to the combination of features defined in the claims but can also be defined by any other desired combination of particular features of all disclosed individual features.

Technology Classification (CPC): 1