Patent Publication Number: US-2010117412-A1

Title: Device and method for adjusting a side cheek of a seat

Description:
The present invention relates to a device and a method for adjusting a side wing of a seat, in particular of a motor vehicle seat, and to a corresponding seat. 
     Side wings are used in a wide variety of motor vehicle seats, in particular in the case of sports seats, in order to provide additional lateral support for a person sitting on a seat. In particular when taking a bend, inertial forces acting on the seat occupant are actively absorbed by the side wings to prevent the person from moving laterally in relation to the seat. To this end, side wings are preferably arranged on the lateral edges of a back rest of the respective seat in order to provide lateral supporting faces for the upper body of the person sitting on the seat. However, many back rests provide only little lateral support, since vehicle seats are frequently designed such that they are suitable for vehicle occupants of various physiques, and side wings are therefore frequently arranged at a position far out on the back rests. 
     In order to allow the side wings to be adjusted individually to the size of the person sitting on the seat in each case, adjustable side wings have been developed. Various devices for adjusting the position or for altering the size of side wings are known from the art. For example, DE 199 50 702 A1 discloses a motor vehicle seat having inflatable side wings, in which air bags for inflating the side wings are provided in the side wings of the seat. 
     Adjusting devices known from the art for side wings, like that described in DE 199 50 702 A1, have the problem that in particular in the case of adjustment using air cushions the back rest contour is altered, rather than the width of the back rest being adjusted. Electromechanical adjusting devices for side wings sometimes have the problem that they are susceptible to damage if, as the seat occupant gets out, he or she touches the side wing and presses it outwards, since electromechanical adjusting devices frequently have only a small amount of play in order for the side wing to absorb the action of a force of this kind. 
     The object of the present invention is therefore to provide an improved adjusting device for a side wing of a seat and an improved method for adjusting a side wing of a seat. In particular, the object of the present invention is to provide an adjusting device for a side wing of a seat which enables the side wing to be adjusted with only a small alteration in the back rest contour. 
     According to the invention, this object is achieved by an adjusting device for a side wing of a seat and a method for adjusting a side wing of a seat as defined in the independent claims. The dependent claims define preferred or advantageous embodiments of the invention. 
     An adjusting device according to the invention for a side wing of a seat includes an adjusting element to be coupled to the side wing, supporting means for mechanically supporting the adjusting element, and pneumatically actuable positioning means for positioning the adjusting element in relation to the supporting means, the positioning means being coupled to the adjusting element in order, when the positioning means are actuated, to reposition the adjusting element for adjusting the side wing. 
     By combining a mechanical support of the adjusting element and a pneumatic actuation thereof by way of the positioning means, it is possible to adjust the side wing such that—in contrast to conventional pneumatic devices—the spatial arrangement of the side wing can be adjusted without at the same time inflating the side wing itself and hence alter its shape. By combining a mechanical support and a pneumatic actuation, the adjusting device according to the invention is furthermore less susceptible to damage in the event of a force acting on the side wing than conventional electromechanical adjusting devices. 
     The positioning means may in particular take the form of an inflatable balloon which has one or more chambers and is made from an elastic material and exerts a force on the adjusting element when it is inflated. 
     In accordance with an example embodiment, the adjusting element is supported pivotally on the supporting means, with the adjusting element including a first and a second portion which are arranged on opposite sides in relation to a point of action of the bearing, and with the positioning means being coupled to the second portion, which is different from the first portion, to be coupled to the side wing. As a result of this configuration, it is possible to avoid the need for the positioning means to be arranged in the side wing itself. For example, the positioning means, for example the inflatable balloon, may be arranged in the back rest of the seat and yet act mechanically on the adjusting element. 
     In accordance with a further example embodiment, the adjusting element is supported displaceably on the supporting means. In this arrangement, a respective stop may be provided for the positioning means on the supporting means and on the adjusting element, with the result that when the positioning means are actuated pneumatically, for example on inflation of the balloon, the positioning means are supported against the stop of the fixed supporting means and, as a result of a force exerted on the stop of the adjusting element, displace the latter in relation to the supporting means. The adjusting element may in this case have at least one curved, for example arcuate, portion. If the adjusting element is supported on the supporting means at its curved portion, then as a result of suitable shaping of the adjusting element a plurality of curved tracks can be defined along which the side wing can be adjusted. 
     The adjusting element may take the form of a curved wire or one or more metal or synthetic tubes, or may include these. A portion of the wire or the metal tube may have moulding around it. As a result of moulding around that portion of the adjusting element which comes into contact with the positioning means and/or which comes into contact with the side wing, it is possible to create a planar abutment surface for the positioning means and/or the side wing. 
     A seat according to the invention includes an adjusting device according to an example embodiment of the invention which is coupled to a side wing of the seat in order to adjust it. To actuate the adjusting device, compressed-air generation means, for example in the form of an electronic air pump or a compressor, which are triggered by electrical control means in dependence on a sensor signal may be provided. If the seat is furthermore provided with a pneumatically actuable lumbar support or another pneumatically actuable device, the latter may be actuated using the same compressed-air generation means as the side wing adjusting device according to the invention. 
     In a method for adjusting the side wing of a seat according to the invention, the side wing is adjusted in that a position of a mechanically supported adjusting element coupled to the side wing is adjusted pneumatically. The method may for example be used with the adjusting device according to the invention. 
     The present invention will mainly be applicable to vehicle seats but is not restricted thereto. 
    
    
     
       The present invention will be explained in more detail below with the aid of preferred example embodiments and with reference to the attached drawing. 
         FIG. 1  is a schematic illustration of a seat having an adjusting device according to the invention, for a side wing. 
         FIG. 2  is a perspective view of an adjusting device according to an example embodiment. 
         FIG. 3  shows schematically the adjusting device of  FIG. 2  in a side view at various points in time during its actuation. 
         FIG. 4  is a perspective view of an adjusting device according to a second example embodiment. 
         FIG. 5  is a further perspective view of the adjusting device of  FIG. 4 . 
         FIG. 6  shows schematically the adjusting device of  FIG. 4  in a side view at various points in time during its actuation. 
         FIG. 7  shows schematically an adjusting device according to a third example embodiment, at various points in time during its actuation. 
     
    
    
     Referring to  FIG. 1 , first a seat having an adjusting device according to the invention, for adjusting a side wing, will be explained.  FIG. 1  shows schematically a view of a back rest  1  of a seat, for example a motor vehicle seat. The back rest  1  includes a seat frame  2  on which two adjustable side wings  3   a  and  3   b  are provided. To adjust the side wings  3   a  and  3   b , two side wing adjusting devices  5   a  and  5   b  are provided, coupled to the side wings  3   a  and  3   b . The adjusting devices  5   a  and  5   b  according to the invention include a mechanically supported adjusting element, the position of which can be set pneumatically, as will be described in more detail below with reference to  FIGS. 2-7 . 
     To actuate the adjusting devices  5   a ,  5   b , an electrical air pump or a compressor  8  is provided which supplies the adjusting devices  5   a ,  5   b  with a fluid, for example air, at positive pressure by way of controllable valves  9   a ,  9   b  and air hoses  11 . The valves  9   a ,  9   b  also have an air vent duct in order to reduce positive pressure. Together with the valves  9   a ,  9   b , the compressor  8  forms compressed-air generation means by means of which the adjusting device is pneumatically actuated. 
     To trigger the compressor  8  and the valves  9   a ,  9   b , in the case of the seat in  FIG. 1  an electronic control unit  7 , for example a processor, is provided which controls the compressor  8  and the valves  9   a ,  9   b  in dependence on output signals from one or more sensors  6 . The sensors may for example be a weight sensor for detecting the fact that a seat is occupied, an ignition switch sensor for detecting an operating state of a vehicle engine, a door sensor for detecting the opening and/or closing of a vehicle door, or a pressure sensor provided on the side wings, which detects the pressure exerted laterally by the side wings on a seat occupant. These sensors make so-called passive back rest width adjustment possible, in which the side wings are adjusted in the direction of the seat occupant when for example a vehicle is in motion and are retracted when the seat occupant wants to sit down on or leave the seat. The sensors  6  may, however, also include an acceleration sensor which for example detects accelerations acting laterally on the seat, with the adjusting devices  5   a ,  5   b  being adjusted in dependence on the lateral acceleration in order to give the seat occupant better lateral support. As a result of this so-called active back rest width adjustment, it is possible when taking a bend for the adjusting device according to the invention to selectively adjust the left-hand side wing  3   b  or the right-hand side wing  3   a , in order to give the person in the seat better support to withstand the centrifugal force acting on him or her. It goes without saying that as an alternative, or in addition, manual triggering of the compressor  8  and the valves  9   a ,  9   b  by the seat occupant may also be implemented, for example by actuating a switch. 
     If a further pneumatically actuable device is provided on the seat, for example a pneumatically actuable lumbar support  4  shown in  FIG. 1 , this may also be provided with compressed air from the same compressor  8  which supplies compressed air to the side wing adjusting devices  5   a ,  5   b.    
     Referring to  FIGS. 2-7 , example embodiments of adjusting devices according to the invention, for side wings of a seat, will be described below. 
       FIGS. 2 and 3  show an adjusting device  20  according to a first example embodiment. The adjusting device  20  includes an adjusting element  21 , a mounting  25  on which the adjusting element  21  is mechanically supported and which serves as a supporting means for supporting the adjusting element  21 , and an elastic balloon  28  (not illustrated in  FIG. 2 ) which is arranged between a supporting plate  27  and a plate-shaped portion  24  of the adjusting element  21 . The adjusting element  21  includes two portions  22  and  23  which are at an angle to one another, with the first portion  22  being coupled to the side wing  3  in the installed state of the adjusting device  20  and the second portion  23  abutting against the balloon  28 . In the example embodiment illustrated, the adjusting element  21  takes the form of a bent wire with two portions  22 ,  23  at an angle to one another, with the plate  24  on which the balloon  28  acts being provided on the portion  23 . The plate  24  may be mechanically secured to the portion  23  of the bent wire, for example by being screwed or glued, or it may take the form of a moulding around this bent wire portion. The portion  22  of the bent wire which is to be coupled to the side wing  3  may also have an element of planar shape, for example a plate (not illustrated in  FIGS. 2 and 3 ) which is screwed on or glued on, or a moulding around it. Even if the bent wire portion  22  is illustrated in the shape of a U with equal legs, the portion  22  which makes contact with the side wing may have any other shape, for example it may be trapezoidal or have curved sides. 
     The adjusting element  21  is supported pivotally on the mounting  25  by means of pins  26 . A helical spring  29  is suspended on the adjusting element  21  and the mounting  29  in order to bias the adjusting element  21  into a rest position and to absorb energy during a change in position of the adjusting element. While the mounting  25  in  FIG. 2  is illustrated to be bar-shaped, it may also for example comprise a plurality of holding plates with which the pins  26  engage. The supporting plate  27  is fixed in its position in relation to the mounting  25  and, in the example embodiment illustrated, is fixedly connected thereto or is made integral therewith. In use, the mounting  25  of the adjusting device  20  is connected to the seat frame  2 , for example by being screwed or welded or with holding brackets. 
       FIG. 3  is a schematic side view of the adjusting device  20  in different operating states in the direction labelled III in  FIG. 2 , that is to say from top in the installed state of the adjusting device  20 .  FIG. 3A  shows a rest condition in which the balloon  28  is not under pressure and is fully compressed, with the result that the portion  23  of the adjusting element  21  is in a position close to the supporting plate  27 . Accordingly, the side wing  3  which is coupled to the portion  22  of the adjusting element  21  is in a rest position.  FIG. 3B  shows an operating state in which the balloon  28  is inflated. Because the supporting plate  27  is arranged to be fixed in its location in relation to the mounting  25 , when the balloon  28  is inflated the adjusting element  21  is pivoted about the position defined by the pins  26 , as indicated by the arrows  31  and  32 . As a result of pivoting the portion  22 , the side wing  3  coupled to the portion  22  is also adjusted, being pivoted in the direction of the seat interior. As a result of an extension of the spring  29 , a counter-force is generated which pivots the adjusting element  21  back into the rest position shown in  FIG. 3A  and at the same time empties the air out of the balloon  28  when the valve  9  is actuated for removing air from the balloon  28 . When air is removed from the balloon  28 , the side wing  3  also returns to its rest position accordingly. 
     As can be seen from  FIG. 3 , in the installed state the balloon  28  is arranged between the portion  23  of the adjusting element  21  and a seat surface  12 . This arrangement is made possible because the two portions  22  and  23  of the adjusting element  21  are arranged on opposite sides of the bearing position defined by the pin  26 , and it has the effect that the balloon  28  can be arranged at positions outside the side wing  3 , for example in the interior of the seat. In the case of the example embodiment of  FIGS. 2 and 3 , inflation of the balloon  28  does not inflate the side wing  3  itself but adjusts it, allowing it substantially to retain its shape. While the balloon  28  in  FIG. 1  is illustrated as a single-chamber balloon, it may also take the form of a multiple-chamber balloon. 
       FIGS. 4-6  show an adjusting device  40  according to a further example embodiment of the invention, with  FIG. 4  being a perspective view,  FIG. 5  being a further perspective view in the direction V in  FIG. 4 , and  FIG. 6  being a schematic side view in the direction VI in  FIG. 4 . 
     The adjusting device  40  includes an adjusting element  41 , a mounting  45  on which the adjusting element  41  is mechanically supported and which serves as a supporting means for supporting the adjusting element  41 , and an elastic balloon  49  having a plurality of chambers  49   a ,  49   b ,  49   c . The adjusting element  41  takes the form of one or more metal or plastic tubes and includes two curved portions  43  and a portion  42  which is at an angle to the curved portions and serves as an abutment surface and stop for the balloon  49 , and in operation is coupled to the side wing  3 . Tabs  50   a ,  50   b ,  50   c  are provided on those sides of the chambers  49   a ,  49   b ,  49   c  of the balloon  49  facing the curved portions  43  of the adjusting element  41 , and these tabs have eyelets  51  through which the curved portions  43  pass, with the result that the balloon  49  is held against the adjusting element  41 . The mounting  45  has two guide portions  46  for the two curved portions  43  of the adjusting element  41 , each of which has a recess  48  and a roller  47  arranged adjacent thereto, or a plurality of rollers, with the curved portions  43  of the adjusting element  41  being guided between those sides of the rollers  47  facing the body of the mounting  45  and the body of the mounting  45 . This allows the rollers  47  to facilitate displacement of the adjusting element  41  in relation to the mounting  45 . The side face  44  of the mounting  45  facing the portion  42  of the adjusting element  41  also serves as an abutment surface or stop for the balloon  49 . 
       FIG. 5  shows in more detail, in a further schematic perspective view in the direction labelled V in  FIG. 4 , the portion of the mounting  45  having the guide portions  46 . Each of the guide portions  46  has a pair of rollers  47  which are arranged adjacent to one another in a longitudinal direction of the curved portions  43 . Those ends of the curved portions  43  of the adjusting element  41  which are on the opposite side to the ends connected to the portion  42  are connected to one another by way of a transverse portion  52  to which an end of a helical spring  53  is coupled, for example being suspended thereon. The other end of the helical spring  53  is coupled to the seat frame  2 , for example being suspended thereon, in order to bias the adjusting element  41  in the direction in which the portion  42  of the adjusting element  41  is arranged close to the mounting  45 . The mounting  45  is mounted on the seat frame, for example by being screwed or welded or with holding brackets. 
       FIG. 6  is a schematic side view of the adjusting device  40  in different operating states in the direction labelled VI in  FIG. 4 , that is to say from top in the installed state of the adjusting device  40 .  FIG. 6A  shows a rest condition in which the balloon  49  is not under pressure and is fully compressed, with the result that the portion  42  of the adjusting element is in a position close to the mounting  45 . Accordingly, the side wing  3  which is coupled to the portion  42  of the adjusting element  41  is in a rest position.  FIG. 6B  shows an operating state in which the balloon  49  is inflated. Because one side of the multiple-chamber balloon  49  abuts against the side face  44  of the mounting  45  and is rested against it, when the balloon  49  is inflated the adjusting element  41  is displaced in relation to the mounting  45 , as indicated schematically by the arrow  54 . Accordingly, the side wing  3  is also adjusted along a curved track. The curve of movement of the portion  42  of the adjusting element  41  and the curve of adjustment of the side wing  3  are in this case substantially defined by the shape of the portions  43  of the adjusting element  41 . Whereas, in the example embodiment illustrated in  FIGS. 4-6 , the portions  43  of the adjusting element are arcuate in shape, they may also have any other suitably defined shape. For example, only some of the portions  43  may be curved, whereas others are straight. As a result of a suitable shaping of the portions  43  and as a result of the arrangement of the guide portions  46  of the mounting, a plurality of desired curves of movement can be produced for the side wing  3 , for example curves of movement in which the side wing  3 , starting at the seat surface, is moved first substantially in a straight line and then along a curve to the interior of the seat. 
     When the balloon  49  is inflated, as a result of an extension of the spring  53  a counter-force is generated which displaces the adjusting element  41  back into the rest position shown in  FIG. 6A  and empties the air out of the balloon  49  when the valve  9  for venting air from the balloon  49  is actuated. When air is vented from the balloon  49 , the side wing  3  also returns to its rest position shown in  FIG. 6A  accordingly. 
     Whereas, in the example embodiment illustrated in  FIGS. 4-6 , the adjusting element  41  takes the form of rigid tubes, it is also possible for the adjusting element to include tubes which may be displaced telescopically in relation to one another and which are extended when the balloon is inflated. In this case, the adjusting element  41  may be connected to the mounting  45  in fixed manner or displaceably. 
       FIG. 7  shows an adjusting device  60  according to a further example embodiment of the invention, in which an adjusting element is both displaced and pivoted, with  FIG. 7A  showing a rest condition and  FIG. 7B  showing an actuated condition. The adjusting device includes an adjusting element  21  configured as described with reference to  FIGS. 2 and 3 , and a mounting  65  which serves as a supporting means and has mounted thereon a supporting plate  67  and an elastic balloon  28  which is in turn arranged between the supporting plate  67  and the portion  23  of the adjusting element  21  which is not coupled to the side wing  3 . The ends of a spring  29  are coupled to the adjusting element  21  and the mounting  65  respectively in order to bias the adjusting element  21  into the rest position shown in  FIG. 3A . 
     The adjusting element  21  is supported pivotally on the mounting  65  by means of a pin  26 . However, the pin  26  is mounted not only rotatably but also displaceably on the mounting  65 . To this end, the mounting  65  has a slot opening  66  in which the pin  26  engages and in which it is guided. When the balloon  28  is inflated, as shown schematically in  FIG. 7B , the pin  26  is displaced in the slot opening  66  and the adjusting element  21  is pivoted about the respective position of the pin  26 . The displacing and pivotal movements are illustrated schematically by arrows  68  and  69  respectively. The two movements may take place at the same time, to a certain extent at the same time, or substantially sequentially, with the sequence of the two movements being determined among other things by the geometric arrangement of the adjusting element  41  and the supporting plate  67  and the properties of stiffness of the side wing  3 . For example, in this way, and as illustrated schematically by the arrow  70 , a movement of the side wing  3  starting at the seat surface  12  and running first substantially in a straight line and then in a curve in the direction of the interior of the seat may be implemented. 
     In each of the example embodiments described with reference to  FIGS. 2-7 , a positive pressure valve may be connected to the balloon which makes it possible to vent air from the balloon when the pressure in the balloon exceeds a particular value, which may occur for example if the seat occupant exerts a pressure on the side wing which is transferred to the balloon by way of the adjusting element. In this case, the action of a great force on the side wing by the occupant results only in the venting of air from the balloon and not in damage to the adjusting device. 
     Whereas in the example embodiments explained in detail above an elastic balloon was used, the positioning means may take the form of any other suitable device which is pneumatically actuable and can exert a force on the adjusting element. 
     The method according to the invention for adjusting side wings of a seat and the adjusting device according to the invention for a side wing are not restricted to use with side wings provided on a back rest. Rather, the method according to the invention and the adjusting device according to the invention may also be applied with seat wings or head rests of a seat. The present invention may be used with any seats, in particular vehicle seats, but is not restricted to the latter.