Abstract:
A longitudinal adjuster ( 3 ) for a vehicle seat ( 1 ) includes at least one rail pair ( 7 ), including a lower rail ( 9 ) and an upper rail ( 11 ), which can be moved longitudinally in relation to the lower rail ( 9 ). At least one locking unit ( 13 ) locks the upper rail ( 11 ). At least one actuating element ( 5 ) releases the locking of the upper rail ( 11 ). The locking unit ( 13 ) includes at least one locking element ( 15 ) and at least one spring element ( 17 ), which are operatively engaged with each other. The spring element ( 17 ) is interlockingly and frictionally connected to the upper rail ( 11 ) by an insertion locking connection (S). The spring element ( 17 ) applies a preloading force to the actuating element ( 5 ) and to the locking element ( 15 ). A vehicle seat ( 1 ) is also provided with at least one such longitudinal adjuster ( 3 ).

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a United States National Phase Application of International Application PCT/EP2015/077877, filed Nov. 27, 2015, and claims the benefit of priority under 35 U.S.C. §119 of German Application 10 2014 225 707.7, filed Dec. 12, 2014, the entire contents of which are incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The invention relates to a longitudinal adjuster for a vehicle seat. The invention furthermore relates to a vehicle seat comprising a longitudinal adjuster of this kind. 
       BACKGROUND OF THE INVENTION 
       [0003]    EP 0 752 338 B1, FR 2 767 096 B1 and EP 0 904 977 B1 each describe a longitudinal adjuster which comprises at least one lower rail and at least one upper rail, which can be moved longitudinally in relation to the lower rail, as well as an elastic element arranged on the upper rail. The elastic element is provided for the purpose of locking the upper rail to the lower rail and, in particular, is arranged on the upper rail by means of a riveted joint. 
       SUMMARY OF THE INVENTION 
       [0004]    It is an object of the present invention to specify a longitudinal adjuster for a vehicle seat which is better than the prior art and to specify an improved vehicle seat. 
         [0005]    A longitudinal adjuster according to the invention for a vehicle seat comprises at least one rail pair, comprising a lower rail and an upper rail, which can be moved longitudinally relative to the lower rail, at least one locking unit for locking the upper rail, and at least one actuating element for releasing the locking of the upper rail. The locking unit comprises at least one locking element and at least one spring element, which are in operative engagement with one another, wherein the spring element is connected to the upper rail in a form- and force-fitting manner by means of a plug-in/latching connection, and wherein the spring element applies a preloading force to the actuating element and to the locking element. 
         [0006]    The plug-in/latching connection of the spring element to the movable upper rail makes possible improved mechanical stability of the longitudinal adjuster in comparison with the prior art since deformation of the upper rail for connection to the spring element and possible distortion of the components resulting from this are avoided. As a result, there is furthermore the possibility of producing the upper rail from a high-strength material. Mechanical stability of the plug-in/latching connection is ensured by the preloading forces produced on the actuating element and the locking element. 
         [0007]    According to one embodiment of the invention, the spring element has at least one latching nose and at least one latching tab, which can be arranged in corresponding apertures in the upper rail to form the plug-in/latching connection. 
         [0008]    In this case, the latching nose can be inserted into a corresponding aperture, and the latching tab can be latched in a different corresponding aperture. 
         [0009]    According to another embodiment of the invention, the aperture corresponding to the latching nose has two regions with widths that differ in the direction of a transverse axis, wherein the latching nose has two sections with widths that differ in the direction of a transverse axis. 
         [0010]    It is expedient here if a respective width of one region of the aperture corresponds to a width of one section of the latching nose. This enables one section of the latching nose to be passed through one region of the aperture and the other section of the latching nose to be arranged in the other region of the aperture to form the plug-in/latching connection. 
         [0011]    To produce the preloading forces, the spring element has two spring arms, wherein one of the spring arms applies a preloading force to the actuating element and the other spring arm applies a preloading force to the locking element. 
         [0012]    In this arrangement, the spring element is preferably designed as a leaf spring, wherein the latching nose and the latching tab are arranged at one face side end of the spring element, and the spring arms are arranged at an opposite face side end of the spring element. By virtue of the fact that the spring arms produce preloading forces at one face side end of the spring element, the spring element is preloaded in such a way that the spring element remains reliably latched in the upper rail by means of the latching nose and the latching tab. 
         [0013]    To fix the position of the actuating element, at least in the direction of a longitudinal axis, which extends parallel to a direction of travel in this case, the actuating element comprises at least one stop, wherein one of the spring arms is in operative engagement with the stop. In this arrangement, the spring arm is preferably in operative engagement with the stop, which applies a preloading force to the actuating element. 
         [0014]    According to another embodiment of the invention, the actuating element is mounted pivotably in a through opening of the spring element. Here, the actuating element is in the form of a rocker, wherein end sections of the actuating element are moved in opposite directions when the actuating element is pivoted. 
         [0015]    In this case, one actuating end of the actuating element is arranged between the locking element and the upper rail. During an actuation of the actuating element, e.g. an upward pivoting movement in the direction of a vertical axis, the actuating end is moved downwards in the direction of the vertical axis and hence in the direction of the lower rail. Since the actuating end is arranged between the locking element and the upper rail, the locking element is moved away from the upper rail and the longitudinal adjuster is unlocked. 
         [0016]    One possibility for the embodiment of the locking element here is a guide peg which is arranged on the locking element and which serves as a guide element for the locking element and serves to stabilize a movement when the locking element is moved from a locking position into an unlocking position and back again. 
         [0017]    A vehicle seat which comprises at least one longitudinal adjuster according to the invention is furthermore provided. 
         [0018]    Here, the vehicle seat has an improved interface for fastening a spring element operatively connected to a locking element, as compared with the prior art. 
         [0019]    Illustrative embodiments of the invention are explained in greater detail with reference to drawings. The present invention is described in detail below with reference to the attached figures. The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which preferred embodiments of the invention are illustrated. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0020]    In the drawings: 
           [0021]      FIG. 1  is a schematic side view showing a vehicle seat having a longitudinal adjuster; 
           [0022]      FIG. 2  is a schematic perspective, partially transparent view showing one illustrative embodiment of a longitudinal adjuster, comprising a rail pair and a locking unit; 
           [0023]      FIG. 3  is a schematic side view showing a section through the longitudinal adjuster in an unactuated state; 
           [0024]      FIG. 4  is a schematic side view showing a section through the longitudinal adjuster in an actuated state; 
           [0025]      FIG. 5  is a perspective, partially transparent view showing an upper rail with an inner locking mechanism; 
           [0026]      FIG. 6  is a schematic exploded view showing the upper rail and a spring element before assembly; 
           [0027]      FIG. 7  is a schematic perspective, partially transparent view showing the upper rail during the assembly of the longitudinal adjuster, wherein the spring element has been inserted into an aperture of the upper rail; and 
           [0028]      FIG. 8  is a schematic perspective, partially transparent view showing the upper rail after assembly, wherein the spring element is latched in an aperture of the upper rail. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0029]    Referring to the drawings, parts that correspond to one another are provided with the same reference signs in all the figures. 
         [0030]      FIG. 1  shows a vehicle seat  1  of a vehicle (not shown specifically) in side view. 
         [0031]    Here, the arrangement of the vehicle seat  1  in the vehicle is defined by means of the coordinate system used below, comprising a vertical axis z associated with a vertical direction of the vehicle, a longitudinal axis x associated with a longitudinal direction of the vehicle, and a transverse axis y associated with a transverse direction of the vehicle. 
         [0032]    The vehicle seat  1  has a longitudinal adjuster  3  according to the invention and an actuating element  5 . When the actuating element  5  is actuated, the vehicle seat  1  can be moved relative to the vehicle along the longitudinal axis x. 
         [0033]    For this purpose, the vehicle seat  1  has a rail pair  7  in the direction of the longitudinal axis x on each side of the vehicle seat, each pair having a lower rail  9  and an upper rail  11 , which can be moved in relation to the lower rail  9  in the direction of the longitudinal axis x. Here, the lower rail  9  is firmly connected to the vehicle, wherein the upper rail  11  is connected to the vehicle seat  1 . 
         [0034]    The longitudinal adjuster  3  according to the invention is described in greater detail below. For this purpose,  FIGS. 2 to 8  show the longitudinal adjuster  3  in various views. 
         [0035]    In particular,  FIG. 2  shows one illustrative embodiment of the longitudinal adjuster  3  in a perspective, partially transparent view, wherein the upper rail  11  is shown as being transparent in some areas.  FIG. 3  shows a section through the longitudinal adjuster  3  in an unactuated state in side view.  FIG. 4  shows a section through the longitudinal adjuster  3  in an actuated state schematically in side view.  FIG. 5  shows the upper rail  11 , in which the locking element  15  is arranged, in a perspective, partially transparent view.  FIG. 6  shows the upper rail  11  illustrated in  FIG. 5  before assembly in a perspective, partially transparent view.  FIG. 7  shows the upper rail  11  during assembly in a perspective, partially transparent view, and  FIG. 8  shows the upper rail  11  after assembly in a perspective, partially transparent view. 
         [0036]    The longitudinal adjuster  3  comprises the rail pair  7  and a locking unit  13 . 
         [0037]    The locking unit  13  is designed to lock the upper rail  11  and comprises at least one spring element  17 , a locking element  15  and the actuating element  5 . 
         [0038]    The actuating element  5  is formed as a handle or hoop (not shown specifically) on an actuating end  5 . 1 . At an opposite unlocking end  5 . 2 , the actuating element  5  is designed as an actuating tongue, which is arranged in the upper rail  11 , in particular between the latter and the locking element  15 . 
         [0039]    The actuating element  5  is arranged in such a way on the spring element  17 , in particular in a through opening  17 . 1  shown in  FIGS. 6 to 8 , that the actuating element  5  is supported as a rocker. When the actuating end  5 . 1  is actuated to unlock the longitudinal adjuster  3 , the opposite, unlocking end  5 . 2  thus moves in an opposite direction. 
         [0040]    The locking element  15  is in the form of a locking plate having lateral rib-shaped latching features  15 . 2  for locking the upper rail  11 . Here, the locking element  15  is positioned between the upper rail  11  and the lower rail  9 . The unlocking end  5 . 2  is arranged between the upper rail  11  and the locking element  15 , as already described above. The locking element  15  furthermore comprises a guide peg  15 . 1 , which projects upwards in the direction of the vertical axis z and which is passed through an opening in the upper rail  11  (not shown explicitly here). 
         [0041]    According to the present illustrative embodiment, the spring element  17  is designed as a leaf spring and has two spring arms  17 . 2 ,  17 . 3 , wherein one spring arm  17 . 2  exerts a substantially perpendicular spring force on the actuating element  5 . In the present case, the spring force is produced along the vertical axis z in the direction of the vehicle seat  1 . Preloading of the actuating element  5  produced by means of the spring force of spring arm  17 . 2  holds said element in a predetermined position, in which the locking element  15  is in a locking position. In the locking position, the lateral latching features  15 . 2  are in operative engagement with latching recesses  9 . 1  arranged in the lower rail  9 , these being shown in part in  FIG. 2 . 
         [0042]    Another spring arm  17 . 3  exerts a substantially perpendicular spring force on the locking element  15 , wherein the spring force holds the locking element  15  in a predetermined position, in particular in the locking position of the locking element  15 . In the present case, the spring force is produced along the vertical axis z in the direction of the vehicle seat  1 . 
         [0043]    During a process of unlocking the longitudinal adjuster  3 , the actuating element  5 , in particular the unlocking end  5 . 2 , is actuated and moved upwards along the vertical axis z in the direction of the vehicle seat  1 . Owing to this movement, in particular the movement of the unlocking end  5 . 2 , and the design of the actuating element  5  as a rocker, the actuating element  5  counteracts the spring force produced by spring arm  17 . 2 , wherein spring arm  17 . 2  is additionally stressed, allowing the actuating end  5 . 1  to be moved back into the original position when it is released. 
         [0044]    The upward movement of the actuating end  5 . 1  along the vertical axis z in the direction of the vehicle seat  1  furthermore brings about a movement of the unlocking end  5 . 2  in the opposite direction, by means of which the spring force of spring arm  17 . 2  is counteracted and the locking element  15  is moved downwards in the direction of the vertical axis z. 
         [0045]    As a result of this, the operative engagement between the latching features  15 . 2  and the latching recesses  9 . 1  is released, and a longitudinal movement of the upper rail  11  relative to the lower rail  9  is enabled. 
         [0046]    In the unlocking position, spring arm  17 . 3  is additionally stressed, ensuring that the locking element  15  is moved back in the direction of the upper rail  11  when the actuating end  5 . 1  is released. Here, the locking position of the locking element  15  is reached when the latching features  15 . 2  latch with the latching recesses  9 . 1 . 
         [0047]    In the figure, the actuating end  5 . 1  of the actuating element  5 , said end being designed as a handle for example, is positioned in such a way that the locking element  15  is in the locking position. 
         [0048]    The spring element  17  has a latching nose  17 . 4 , which is arranged in a corresponding aperture  11 . 1  in the upper rail  11  to form a plug-in connection. The spring element  17  furthermore has a latching tab  17 . 5 , which is arranged in a corresponding further aperture  11 . 2  in the upper rail  11  to form a latching connection and to fix a position of the latching nose  17 . 4  in aperture  11 . 1 . Together with the corresponding apertures  11 . 1 ,  11 . 2 , the latching nose  17 . 4  and the latching tab  17 . 5  form a plug-in/latching connection S. 
         [0049]    The actuating element  5  is passed through a through opening  17 . 1 . Here, the actuating element  5  is supported in such a way in the through opening  17 . 1  (in a manner not shown specifically) that the actuating element  5  is designed as a rocker, as already mentioned above. In a region of the through opening  17 . 1 , the actuating element  5  furthermore has lateral stops (not shown) in order to define and stabilize a position of the actuating element  5  in the spring element  17 . 
         [0050]    To fix the position of the actuating element  5 , at least in the direction of the longitudinal axis x, said element has a further stop  5 . 3 , on which spring arm  17 . 2  is arranged. By virtue of the spring force produced by means of spring arm  17 . 2 , the arm is pressed against the actuating element  5  and a steady arrangement on the stop  5 . 3  is ensured. 
         [0051]    The other spring arm  17 . 3  exerts the spring force on the locking element  15  along the vertical axis z in the direction of the vehicle seat  1 , thereby holding said locking element in the position shown. 
         [0052]    The unlocking end  5 . 2 , which is designed as an actuating tongue, is arranged between an inner side of the upper rail  11 , said inner side facing the lower rail  9 , and the locking element  15 . Locking element  15 , on which the spring force produced by means of spring arm  17 . 3  is exerted, transmits this spring force to the unlocking end  5 . 2 , thereby pressing said end against the upper rail  11 . In order to minimize mechanical noises during an actuation of the actuating element  5 , the unlocking end  5 . 2  comprises a damping element  5 . 4 , e.g. a rubber plug or a plastic coating or a spring. 
         [0053]    To actuate the actuating element  5  and thus unlock the longitudinal adjuster  3 , the actuating end  5 . 1  is moved along the vertical axis z in the direction of the vehicle seat  1  in accordance with the arrow P shown in  FIG. 4 . 
         [0054]    Owing to the movement of the actuating end  5 . 1  and the design of the actuating element  5  as a rocker, the actuating element  5 , in particular the unlocking end  5 . 2 , counteracts the spring forces produced by the spring arms  17 . 2 ,  17 . 3 . The movement of the actuating end  5 . 1  along the vertical axis z in the direction of the vehicle seat  1  furthermore has the effect that the unlocking end  5 . 2  is moved in the opposite direction. 
         [0055]    During this process, the locking element  15  is moved downwards along the vertical axis z and hence into the unlocking position by means of the unlocking end  5 . 2 . 
         [0056]    The connection between the spring element  17  and the upper rail  11  is explained in greater detail below. 
         [0057]    The upper rail  11  has the aperture  11 . 1  in a flank extending in the direction of the longitudinal axis x. The aperture  11 . 1  is of substantially T-shaped design to allow the spring element  17  (not shown here) to be accommodated in a form-fitting and force-fitting manner. In this case, the aperture  11 . 1  has two regions with different widths X 1 , X 2  in the direction of the transverse axis y, wherein the width X 1  of a region facing the locking element  15  in the direction of the longitudinal axis x is smaller than the width X 2  of the other region. 
         [0058]    A further aperture  11 . 2  is arranged spaced apart from aperture  11 . 1  in the direction of the longitudinal axis x and is likewise provided for accommodating the spring element  17  in a form-fitting and force-fitting manner. 
         [0059]    The spring element  17  has a latching tab  17 . 5  to enable it to be fixed in position on the upper rail  11 . The latching tab  17 . 5  is produced by means of stamping and subsequent forming, for example, or, as an alternative, is designed as a latching pin projecting from the spring element  17  or as a separate latching pin arranged on, e.g. welded on, the spring element  17 . Here, the latching tab  17 . 5  has a width corresponding to the further aperture  11 . 2  in the direction of the transverse axis y. 
         [0060]    In the present case, the spring element  17  is of integral design, wherein the latching nose  17 . 4  has been shaped by means of stamping and subsequent forming, for example. In an illustrative embodiment which is not shown, the latching nose  17 . 4  is arranged, e.g. screwed on, by means of a force-fitting and/or form-fitting connection. 
         [0061]    The latching nose  17 . 4  extends vertically along the vertical axis z and is of substantially T-shaped design. Here, a wide section of the latching nose  17 . 4 , which is towards the top along the vertical axis z, has a width X 3 , and a lower, narrow section has a width X 4 . In this arrangement, the width X 2  of the aperture  11 . 1  corresponds to the width X 3  of the latching nose  17 . 4 , and the width X 1  of the aperture  11 . 1  corresponds to the width X 4  of the latching nose  17 . 4 . 
         [0062]    The spring arms  17 . 2 ,  17 . 3  extend along the longitudinal axis x and are formed so as to be spaced apart in such a way that they can apply separate spring forces. 
         [0063]    Spring arm  17 . 2  is angled in such a way along the transverse axis y at an opposite end from latching nose  17 . 4  that it is possible to produce engagement of spring arm  17 . 2  with the stop  5 . 3  of the actuating element  5 . 
         [0064]    Spring arm  17 . 3  is of arched design at an end opposite the latching nose  17 . 4 , in such a way that an additional spring force action on the locking element  15  is achieved. 
         [0065]      FIG. 7  shows an assembly step in which the spring element  17 , in particular the latching nose  17 . 4 , is introduced into the aperture  11 . 1  of the upper rail  11 . During this process, the upper region with the width X 3  of the latching nose  17 . 4  is passed through the wide region X 2  of aperture  11 . 1 . 
         [0066]      FIG. 8  shows the longitudinal adjuster  3  after assembly, wherein the spring element  17  has been moved longitudinally out of a position shown in  FIG. 7  in the direction of the locking element  15 . During this process, the latching nose  17 . 4  is latched into the aperture  11 . 1  of the upper rail  11 . The narrow region of the latching nose  17 . 4  is guided into the narrow region of aperture  11 . 1 , and the latching tab  17 . 5  is latched in the further aperture  11 . 2 . By means of the arrangement of the latching tab  17 . 5  in the further aperture  11 . 2 , the latching nose  17 . 4  is fixed in its position. 
         [0067]    The described arrangement of the spring element  17  on the upper rail  11  is a plug-in/latching connection S. The preloading forces of the spring element  17  on the locking element  15  and on the actuating element  5  hold the spring element  17  in the upper rail  11 . 
         [0068]    Forces acting externally on the actuating element  5  along the vertical axis z do not produce any moments on the spring element  17  by means of latching of the spring element  17  in the apertures  11 . 1 ,  11 . 2 , which are situated in one plane. Tension and compression forces along the longitudinal axis x can be absorbed by the spring element  17 . 
         [0069]    While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.