Abstract:
An actuating unit of a motor vehicle seat comprises an actuating element, a base part, a pivot axis, and a spring. The pivot axis is disposed between the base part and the actuating element and enables a pivoting movement of the actuating element relative to the base part. The spring is disposed between the actuating element and the base part and elastically biases the actuating element into a rest position relative to the base part.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of International Patent Application No. PCT/EP2009/054254, filed on Apr. 8, 2009 and claims priority to German Patent Application 10 2008 021 123.0, filed Apr. 28, 2008. The entire disclosure of both of these applications is incorporated by reference herein. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The invention relates to an actuating unit of a motor vehicle seat, comprising an actuating element, a base part, a pivot axis, which is disposed between the base part and the actuating element and enables a pivoting movement of the actuating element relative to the base part, and a spring, which is disposed between the actuating element and the base part and elastically biases the actuating element into a rest position relative to the base part. 
       BACKGROUND OF THE INVENTION 
       [0003]    U.S. Pat. No. 2,285,616 discloses an actuating unit of a motor vehicle seat. In this case, the base part is formed as a beam which is rigidly connected to the seat rail. The actuating element is a locking lever comprising a locking member engaging into a latching strip connected in the floor rail. A pivot axis is disposed parallel to the longitudinal adjustment direction of the rails, it reaches through bearing openings of the base part and the actuating element. Finally, a spring is provided, which is fitted onto the pivot axis, is supported by the base part on the one hand and by the actuating element on the other hand, and which elastically biases the actuating element into a rest position relative to the base part, wherein this rest position is the engaging position into the latching strip. 
         [0004]    Such actuating units have proved themselves in principle; they have been used for a long time. Nevertheless, they have drawbacks. For example, the installation effort is considerable. Though the pivot axis is easy to install, it must, however, be secured against axial movement by additional means. Additional room is required on the pivot axis for accommodating the spring. The spring must be hooked in separately after it has been pushed onto the pivot axis. The known actuating unit has many separate parts. 
       SUMMARY OF THE INVENTION 
       [0005]    The present invention further develops the known actuating unit to simplify storage and installation. 
         [0006]    In accordance with the invention, the components pivot axis and spring, which had hitherto always been formed to be separate, are now combined in an integral spring element. Together with its axis part, this spring element forms the pivot axis. This axis part is also mounted in a way corresponding to that of the pivot axis according to the prior art, However, the axis part does not have to be axially secured by additional means such as stopping elements as used in the prior art, rather, no separate stopping elements are allocated to the axis part itself. The axis part is axially secured by at least one remaining partial area of the spring element being retained in at least one location. It is advantageous for this purpose if a retaining means fixing the second end portion of the spring element is provided on the base part or on the actuating element. 
         [0007]    Preferably, the axis part of the spring element also acts as a support for the elastic action of the spring element. A separate counter-bearing, for example a hole for hooking in the spring in accordance with the prior art, becomes superfluous. The spring part of the actuating unit according to the invention preferably is not configured anymore as a helical or leg spring, but preferably has a sufficiently long spring leg which provides the spring deflection required for the pivoting movement. 
         [0008]    Preferably, the spring element has a supporting part which is in elastic contact with the actuating element, Optionally, it can execute a relative movement relative to the actuating element during the pivot actuation of the actuating element. 
         [0009]    On the whole, the invention makes it possible to install the entire combined component, that is, the spring element, with the same installation effort required in the prior art for installing the spring alone. The installation effort for installing a separate pivot axis and axially securing it can be omitted. 
         [0010]    Preferably, the spring element is produced from a bar material with a round cross section. The cross section is dimensioned sufficiently for the axis part to have a sufficient cross section in the bearing area; for example, the diameter of the cross section is greater than one, preferably than 1.5 mm. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]    Other advantages and features of the invention will become apparent from the other claims as well as from the following description of exemplary embodiments of the invention, which are to be understood not to be limiting and which will be explained below with reference to the drawing. In the drawings: 
           [0012]      FIG. 1 : shows a perspective view of a longitudinal adjustment device with a pair of rails; 
           [0013]      FIG. 2 : shows a cut along the sectional plane designated II-II in  FIG. 1 ; 
           [0014]      FIG. 3 : shows a perspective view of a longitudinal adjustment device as in  FIG. 1 , but in this case with a multi-pin locking device; 
           [0015]      FIG. 4 : shows a cut along the sectional plane IV-IV in  FIG. 3  at an enlarged scale; 
           [0016]      FIG. 5 : shows a cut along the sectional plane V-V in  FIG. 3  or  FIG. 6  at an enlarged scale; 
           [0017]      FIG. 6 : shows a perspective view of a longitudinal adjustment device as in  FIG. 3 , but in this case for a push-in installation of the axis part in the reversed longitudinal direction, namely from the right; 
           [0018]      FIG. 7 : shows a cut along the sectional plane VII-VII in  FIG. 6  at an enlarged scale; 
           [0019]      FIG. 8 : shows a top view onto an actuating unit in the form of a pivotable cam pivoted relative to a base part; and 
           [0020]      FIG. 9 : shows a cross-sectional view along the line of cut IX-IX in  FIG. 6 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0021]    The inventive actuating unit according to the first three exemplary embodiments, that is,  FIG. 1  and  FIG. 2  for the first exemplary embodiment,  FIG. 3  to  FIG. 5  for the second exemplary embodiment, and  FIG. 6  and  FIG. 7  for the third exemplary embodiment, is provided in each case with a pair of rails for a longitudinal adjustment device. The pair of rails has a floor rail  20  and a seat rail  22 . A window  24  is formed in the seat rail  22 . The floor rail  20  forms a latching strip  26 . Two bearing blocks  28  protrude on the seat rail  22 , transverse to the longitudinal direction of the rail  20 ,  22 ; they form a base part  29  and have a bearing opening each. 
         [0022]    The first exemplary embodiment, in particular, is described below: an actuating element  30  is provided which is inserted through the window  24  in the seat rail  22 . The actuating element  30  comprises a blocking arm  32  which reaches through a shearing opening  34  of the seat rail  22  and is in engagement with the latching strip  26 . With is free end, it lies in the immediate vicinity of a free leg of the seat rail  22 . It may or may not be in contact with this free leg. The actuating element  30  comprises bearing pieces  36  bent upwards, in each of which a bearing opening is located. 
         [0023]    The base part  29  is firmly connected with the seat rail  22 . The base part  29  is formed by two bearing blocks  28 , the two bearing blocks  28  are cut free from the material and bent out of the seat rail  22 ; they each comprise a bearing opening. 
         [0024]    The above-described bearing openings of the base part  29  and of the actuating element  30  are aligned. An axis part  38  of a spring element  40  is pushed through them. The axis part  38  forms a first end portion of the spring element  40 . Subsequent to the axis part  38 , the spring element  40  furthermore comprises a transverse part  42  extending transversely to the longitudinal direction of the rails  20 ,  22 . In turn, this transverse part  42  transitions into a support part  44 . This is followed in turn by a spring portion  46 . The second end portion  48  follows the spring portion  46 ; the end portion is pushed through a hole  50  of the seat rail  22  and fixed therein. A retaining means for the second end portion  48  is thus formed. 
         [0025]    The actuating element  30  is designed as a two-armed lever. The outer lever arm, just like in the prior art, is provided with or connected to a handle (not shown). The support part  44  rests elastically on the underside of the outer lever arm. If the actuating element  30  is pivoted out of the rest position shown and in accordance with the arrow  52  in order to release the locking device, the spring portion  46  deforms; the support part  44  can also be displaced relative to the actuating element  30  in the process. The spring portion  46  can be rectilinear, but it may also have at least one bend, as shown. It is configured such that the desired elastic force is provided at the actuating clement  30 . 
         [0026]    The second exemplary embodiment will be discussed below; in particular, differences to the first exemplary embodiment will be explained. In the second exemplary embodiment, the base part  29  is a separate part connected to the seat rail  22 . Bearing openings are once again formed. An actuating element  30 , which is pushed through the window  24  of the seat rail, is also provided. However, it does not itself have a locking function in this case. Rather, a number of arresting pins  32  as they are known in principle from the prior art, see for example U.S. Pat. No. 4,189,957, are provided. From the latched position of at least one of the arresting pins  32 , which is normally provided (in this regard, see  FIG. 4 ), all arresting pins  32  are pulled free into a release position against the action of an engaging spring  54  by a fork arrangement, which is provided on the inner lever arm of the actuating element  30 , reaching under the arresting pins  32  on a collar, on which the engaging spring  54  is also supported, and pushing them free. The engaging springs  54  are located within a channel cavity enclosed by the two rails  20 ,  22 . In order to be able to install the arresting pins  32  including their engaging springs  564  sufficiently large holes are provided in the upper flange of the seat rail  22 , After the installation of the arresting pins  32  including their engaging springs, the base part  29  is installed from above; it has openings for the arresting pins  32  which are adapted to the diameter of the arresting pins  32  themselves and are smaller then the holes of the seat rail  22 . Thus, the engaging spring  54  can support itself on the underside of the base part  29 . 
         [0027]    The base part  29 , in the area in which it is in contact with the axis part  38 , either has a bead in which the axis part  38  gathers, or partial areas of the actuating element  30  are cut free transversely to the direction of the pivot axis and deformed in such a way that they are able to reach over the axis part  38 , so that, on the whole, a channel for the axis part  38  is formed. In contrast to the first exemplary embodiment, the support part  44  lies in a bead formed at the outer lever arm. It position is fixed thereby. 
         [0028]    The third exemplary embodiment according to the  FIGS. 6 and 7  differs from the second exemplary embodiment with regard to the installation direction when the axis part  38  is inserted. Whereas this installation is carried out in the second exemplary embodiment from the left hand side, that is, in the direction of the arrow for the cut V-V, the axis part  38  is inserted from the right hand side in the third embodiment. In order to make this possible, the transverse part  42  can now be found on the other side of the base part  29 , and a partial piece of the spring element  40  extending parallel to the axis part  38  or the support part  44  is now additionally provided between the transverse part  42  and the support part  44 . The spring element  40  now extends in an S-shape. 
         [0029]    The fourth exemplary embodiment shows an actuating unit as it is used at another location of the seat, that is, outside of the longitudinal guide, e.g. an arresting cam as as it is known from DE 10 2005 026 861 A1 as component ( 64 ); it is used to fix a back-rest in a position folded forward. However, the actuating unit may also fulfill other functions, for example, be a handle for triggering the seat to fold forward, as it is describe as component ( 32 ) in DE 10 2004 057 106 A1. 
         [0030]    The base part  29  is now a partial piece of a seat support or of a backrest support or of another component of the seat. The actuating element  30  is designed as a cam. It can pivot about a pivot axis defining the axis part  38 . This axis part  38  reaches through a bearing bore in the base part  29  and a bearing bore in the actuating element  30 . Again, the axis part  38  forms a first end portion of the spring element  40 . The subsequent transverse part  42  is fixed underneath a pushed-up flap  56 , which is pushed out of the material of the actuating element  30 . Though it may come clear therefrom in a down-ward direction, that is, by counter-clockwise rotation about the pivot axis, but is prevented from doing so by the spring force of the spring element  40 . The spring element  40  then has one and a half windings and then merges towards the right side into the second end portion  48 . The latter reaches under a retaining part  58  which is formed similar to the flap  56  but points in the opposite direction and is now formed from the material of the base part  29 . It is possible to push the flap  56  and/or the retaining part  58  downwards at the free end once the installation has been carried out, in order thus to mechanically fix the transverse part  52  or the second end portion  48 . 
         [0031]    A stop  60  is provided against which the cam, that is, the actuating element  30 , rests elastically. The stop  60  protrudes from the base part  29 .