Abstract:
A belt buckle feeder comprises a base ( 12 ) adapted to be fixedly attached to the vehicle and a carriage ( 14 ) being movably supported on the base ( 12 ) to which carriage a belt buckle ( 20 ) can be coupled and which can be moved by a drive arranged on the base ( 12 ). The drive includes an electric motor ( 26 ) and a worm gear comprising a worm shaft ( 34 ) which has a worm ( 36 ) as well as drive spur wheel teeth ( 40 ), with the shaft ( 28 ) of the electric motor ( 26 ) including a pinion ( 30 ) which is engaged in the drive spur wheel teeth ( 40 ) and drives the worm shaft ( 34 ).

Description:
RELATED APPLICATIONS 
       [0001]    This application corresponds to PCT/EP2015/001919, filed Sep. 29, 2015, which claims the benefit of German Application No. 10 2014 015 340.1, filed Oct. 17, 2014, the subject matter of which are incorporated herein by reference in their entirety. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The invention relates to a belt buckle feeder. 
         [0003]    Belt buckle feeders facilitate fastening and unfastening of a seat belt in that the bait buckle is reversibly moved, by means of a drive, from a retracted position in which it is no obstacle to the vehicle occupant during normal driving operation to an extended position in which the vehicle occupant may easily reach the belt buckle. 
         [0004]    It is felt to be especially comfortable when the belt buckle in the extended position moves toward the vehicle occupant so as to facilitate insertion of the plug-in tongue. 
       SUMMARY OF THE INVENTION 
       [0005]    It is the object of the invention to provide a compact cost-efficient belt buckle feeder which is comfortable for the occupant. 
         [0006]    This is achieved with a belt buckle feeder comprising a stationary base which is adapted to be fixedly mounted on the vehicle and a carriage movable to a retracted position and to an extended position vis-à-vis the base, with the carriage being connected to a belt buckle by an intermediate plate provided between the belt buckle and the carriage. The intermediate plate is tightly connected to the belt buckle and there is provided a positive guidance by which the intermediate plate is pivoted vis-à-vis the carriage about a predetermined degree during traversing to the extended position so that, in addition to the traversing movement of the carriage along a tilting direction, the belt buckle reversably tilts from a home position into an inclined position. 
         [0007]    The use of a positively guided intermediate plate rigidly connected to the belt buckle helps to integrate the mechanism for inclining the belt buckle at least largely into the carriage and/or the base of the belt buckle feeder, where it is protected from environmental influences. 
         [0008]    The intermediate plate can be arranged, for example, on a fixing bolt tightly connected to the carriage which reaches through an opening in the intermediate plate. In this way, a simple and cost-efficient as well as robust pivoting option is created. The fixing bolt may be a stepped rivet comprising a shoulder the diameter of which is larger than the diameter of the opening in the intermediate plate. In this manner the tilting of the intermediate plate can be limited. The shoulder may also serve as a lower counter-bearing point, when the tension element exerts a force on the intermediate plate. 
         [0009]    Preferably, a spring element is provided for exerting a force along the tilting direction on the intermediate plate. Accordingly, the belt buckle can be loaded into the inclined position by the spring action. Alternatively, the spring may act as a resetting element and exert a force on the belt buckle into the home position. 
         [0010]    Advantageously, the spring element is fixed on the carriage so as to ensure sufficient force acting on the intermediate plate. 
         [0011]    The maximum angle of inclination about which the belt buckle is tilted from the home position to the inclined position ranges from 5 to 15°, especially from 7 to 12°, for example. 
         [0012]    The tilting direction is preferably selected to be parallel to the fixing bolt. 
         [0013]    In the home position the belt buckle may be upright so that its longitudinal axis is congruent with the longitudinal axis of the carriage or it may be inclined already vis-à-vis the longitudinal axis of the carriage. 
         [0014]    It is of advantage in this embodiment when the spring element loads the intermediate plate into the home position, i.e. serves as a resetting element, when the belt buckle is moved to the retracted position again and the tensile force acting on the intermediate plate subsides. In this way, the belt buckle is retained in the home position even in the retracted position of the carriage. An inclination of the belt buckle takes place only at the end of the traversing movement in the vicinity of the extended position. According to a second preferred embodiment, the positive guidance comprises a rigid link plate tightly arranged on the base which is configured so that the intermediate plate moves to its inclined position during the traversing movement to the extended position of the carriage. For this purpose, the spring element includes a pressure section acting on the intermediate plate and loading the letter into the inclined position. 
         [0015]    The intermediate plate preferably abuts on the link plate with its lower carriage-side end. During the traversing movement to the extended position, the force exerted on the intermediate plate by the link plate subsides so that the intermediate plate including the belt buckle pivots to the inclined position by the effect of force of the spring element. When the carriage is returned to the retracted position, a resetting force is exerted via the link plate on the intermediate plate which compensates the spring force and sets the intermediate plate into its home position again. 
         [0016]    In order to realize this movement the link plate is inclined away from the intermediate plate e.g. toward the belt buckle and a carriage-side end of the intermediate plate slides along the link plate in the direction of movement. 
         [0017]    The inclination of the link plate along the traversing direction may be constant so that during the traversing movement the belt bookie inclines uniformly toward the vehicle occupant. The link plate could also be stepped or formed to have different inclinations, however, so as to cause a discontinuous inclination movement of the belt buckle. 
         [0018]    The use of a uniformly inclined link plate easily enables the inclination movement of the belt buckle to start already upon the beginning of the traversing movement. It is also possible, however, to cause an inclination movement only at the end of the traversing movement to the extended position by an appropriate shape of the link plate. 
         [0019]    The link plate may include two parallel arms encompassing the fixing belt in the retracted position of the carriage so that a symmetric load of the intermediate plate during the traversing movement and thus uniform inclination of the belt buckle is obtained. 
         [0020]    The link plate preferably is a formed sheet metal part which can be easily manufactured at low cost. 
         [0021]    In a first preferred embodiment the positive guidance includes a tension element acting on the intermediate plate. 
         [0022]    The tension element may be formed so that at the end portion of the traversing movement of the carriage into the extended position it contacts an engageable element on the base and is retained by the latter, wherein an increasing tensile force acting on the tension element is produced. The engageable element is arranged rigidly, tightly and non-displaceably on the base, for example in the form of a projection which the tension element will contact from a particular position in the traversing path. In such design, the belt buckle does not start to incline out of its home position before the end portion of the traversing movement is reached and the tension element is loaded. On the other hand, during the traversing movement taking place before it remains in its home position. The end portion may begin, for example, about 5 to 15 mm before the maximum extended position is reached. 
         [0023]    The tension element is preferably flexible and in particular is a wire or a rope. The tension element substantially should not be elastic, however, for exactly transmitting a tensile force. When the tension element is designed as a wire loop, for example, also non-straight extensions of the tension element can be easily realized without a complex three-dimensional component having to be manufactured. 
         [0024]    Advantageously, the tension element acts on the intermediate plate along the tilting direction offset against a center of gravity of the intermediate plate so that a tensile force acting on the tension element generates a torque onto the intermediate plate. 
         [0025]    For this, on the intermediate plate two securing tabs arranged on opposite longitudinal sides end projecting along the tilting direction may be disposed, with the tension element acting on the securing tabs. If the tension element is a wire loop, for example, the free ends of the wire are connected to the securing tabs. For this purpose, openings or recesses through which the tension element extends may be provided. 
         [0026]    The securing tabs are preferably arranged on the belt buckle side of the opening in the intermediate plate so as to achieve an as large lever stroke as possible. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0027]    Hereinafter the invention shall be illustrated in detail by way of two embodiments with reference to the attached drawings, wherein: 
           [0028]      FIG. 1  shows a schematic perspective representation of a belt buckle feeder according to the invention in accordance with a first embodiment; 
           [0029]      FIG. 2  shows the belt buckle feeder from  FIG. 1  in a front view; 
           [0030]      FIG. 3  shows the belt buckle feeder from  FIG. 1  in a perspective schematic rear view; 
           [0031]      FIG. 4  shows a schematic perspective view of an intermediate plate of the belt buckle feeder from  FIG. 1 ; 
           [0032]      FIG. 5  shows a schematic side view of the belt buckle feeder from  FIG. 1 ; 
           [0033]      FIG. 6  shows a schematic perspective detailed view of the belt buckle feeder from  FIG. 1 ; 
           [0034]      FIG. 7  shows details of the belt buckle feeder from  FIG. 1  in a schematic side view; 
           [0035]      FIG. 8  shows the belt buckle feeder from  FIG. 1  in the completely extended position in a front view; 
           [0036]      FIG. 9  shows the belt buckle feeder from  FIG. 3  in a schematic side view; 
           [0037]      FIG. 10  shows a schematic detailed view of a belt buckle feeder according to the invention in accordance with a second embodiment; 
           [0038]      FIG. 11  shows an intermediate plate of the belt buckle feeder from  FIG. 10  in a schematic perspective view; 
           [0039]      FIG. 12  shows details of the belt buckle feeder from  FIG. 10  in a schematic perspective view; and 
           [0040]      FIGS. 13 to 16  show schematic views of the belt buckle feeder from  FIG. 10  during the movement from the completely retracted position to the completely extended position. 
       
    
    
     DESCRIPTION 
       [0041]      FIG. 1  illustrates a belt buckle feeder  10  comprising a base  12  (indicated only) and a carriage  14  supported on the base  12  to be movable along an axial direction A in a traversing direction V of the belt buckle feeder  10 . The base  12  is tightly fixed to the vehicle. 
         [0042]    The carriage  14  encompassing the base  12  in portions and being U-shaped or box-shaped in cross-section has a gear rack structure  16  which is formed at parallel narrow sides  18  of the carnage  14 . 
         [0043]    On the carriage  14  a belt buckle  20  is secured via a rigid intermediate plate  22  which is rigidly connected to the belt buckle  20  by means of two securing openings  24  (cf.  FIGS. 3 and 4 ). 
         [0044]    The carriage  14  and thus the belt buckle  20  can be moved, via a linear drive (not shown) on the base  12 , by means of the gear rack structure  16  from a completely retracted position shown in  FIGS. 1 and 2  to a completely extended position shown in  FIGS. 8 and 9 . 
         [0045]    The intermediate plate  22  (cf.  FIG. 4 ) includes an opening  26  through which a fixing bolt  28  being connected to the carriage  14  fixed in position is reaching. The fixing bolt  28  in this case is in the form of a stepped bolt (cf. e.g.  FIG. 5 ) comprising a first section  28   a  having a smaller diameter than the opening  28  in the intermediate plate  22  and a second section  28   b  having a larger diameter than the opening  26 . 
         [0046]    The section  28   a  extends along the fixing bolt  28  over more than the width of the intermediate plate  22 , for example over twice to three times the width thereof, so that the intermediate plate  22  may tilt along the section  28   a  vis-à-vis the fixing bolt  28 . 
         [0047]    This allows for inclining the belt buckle  20  vis-à-vis the carriage  14  in a tilting direction N about a predetermined angle so that the belt buckle  20  may adopt a home position and an inclined position. 
         [0048]    In the home position which the belt buckle  20  adopts in the retracted position of the belt buckle feeder  10 , the belt buckle  20  is upright in these examples (see e.g.  FIGS. 1 and 2 ). The inclined position, on the other hand, is adopted by the belt buckle  20  in the completely extended position of the belt buckle feeder  10  (see e.g.  FIGS. 8 and 9 ). The maximum angle of inclination α ranges from 5° to 15° and especially from 7° to 12°, for example. 
         [0049]    The movement of the carriage  14  between the retracted position and the extended position is carried out reversibly and serves for rendering the fastening and unfastening of a seat belt more comfortable for the vehicle occupant. The comfort is increased in that the belt buckle  20  in the extended position is simultaneously pivoted to the inclined position so that it is conveniently accessible for the vehicle occupant. For a normal driving operation, the carriage  14  is moved to the retracted position with the belt buckle  20  adopting its home position, the upright position in this case, again. 
         [0050]    The pivoting movement is carried out without any separate drive, rather the pivoting movement is derived by a mechanism from the vertical traversing movement. 
         [0051]    In the first embodiment shown in  FIGS. 1 to 9 , a tension element  30  is provided for positively guiding the intermediate plate  22  so as to move the belt buckle  20  from the home position along the tilting direction N to the inclined position. 
         [0052]    The tension element  30  in this case is realized in the form of a wire strap which is secured by its free ends  32  to the intermediate plate  22  and in a loop  34  protrudes into the carriage  14  (cf.  FIG. 1 ). 
         [0053]    At the intermediate plate  22  two securing tabs  36  located on the two opposite longitudinal sides of the intermediate plate  22  and projecting from the intermediate plate  22  along the tilting direction N are formed, wherein each of the securing tabs  36  includes a securing opening  38  through which an end  32  of the tension element  30  is pulled. The securing openings  38  are distanced from a body of the intermediate plate  22  so far that the tension element  30  acts outside the center of gravity of the intermediate plate  22  and a tensile force F Z  acting on the securing tabs  36  results in tilting of the intermediate plate  22  on the fixing bolt  28 . 
         [0054]    The securing tabs  36  are provided on the belt-buckle side end of the intermediate plate  22  approximately level with the securing openings  24 , whereas the opening  26  is formed on the carriage-side end of the intermediate plate  22  so that adequate leverage for tilting the intermediate plate  22  is generated. 
         [0055]    The base  12  includes an engageable element  40  (not shown in detail), for example in the form of a projection or a hook, which is contacted by the tension element in an end portion of the traversing movement to the extended position so that it is retained on the same. In this way, during further traversing in the direction of the extended position a tensile force which is transmitted via the securing tabs  36  to the intermediate plate  22  and thus to the belt buckle  20  secured thereto is exerted on the tension element  30 . As a consequence, the belt buckle  20  tilts along the tilting direction N up to its tilted position. 
         [0056]    In the shown embodiment, the tension element  30  freely extends over the majority of the traversing movement within the carriage  14  without contacting the engageable element  40 . Merely for the last section of the traversing movement, approximately the last 5 to 15 mm, the tension element  30  abuts on the engageable element  40  and is retained by the latter so that the belt buckle  20  tilts. 
         [0057]    During return to the retracted position the tension element  30  becomes disengaged from the engageable element  40  again. 
         [0058]      FIG. 2  illustrates the belt buckle feeder  10  in its completely retracted position in which no movement of the carriage  14  along the shifting direction V has taken place so far (□V 0 ). 
         [0059]      FIGS. 8 and 9 , on the other hand, illustrate the belt buckle feeder  10  in the maximally extended position in which the maximum shift distance □V max  has been covered. 
         [0060]    A spring element  42  provides a reselling force which loads the belt buckle  20  into the home position. The spring element  42  in this case is bent from a wire and is wound by plural spiral windings in a section  42   a  about the section  28   a  of the fixing bolt  28 . A first tree end  42   b  of the spring element  42  is tightly connected to the carriage  14 , while a second free end  42   c  in the area of the securing tabs  36  acts on the intermediate plate  22 . In this way, the end  42   c  of the spring element  42  pulls the belt buckle  20  in the direction of the section  26   b  of the fixing bolt  28  into the home position thereof and thus produces a counter-force to the tensile force applied via the tension element  30 . The force applied by the spring element  42  is chosen to be smaller than the force to be applied by the tension element  30  so that the belt buckle  20  may tilt along the tilting direction. When the tensile force is omitted, the spring element  42  produces a resetting force F, however, which pulls the intermediate plate  22  and thus the belt buckle  20  back to the home position. 
         [0061]    Moreover, the belt buckle feeder  10  includes electric connecting cables  44  (cf.  FIG. 1 ) extending toward the belt buckle  20  and being connected, for example, to a sensor for detecting the plug-in of a plug-in tongue. 
         [0062]      FIGS. 10 to 16  illustrate a belt buckle feeder  100  in accordance with a second embodiment. 
         [0063]    Components known from the first embodiment already and being present in an identical or only slightly modified form will maintain their previously inserted reference numerals. 
         [0064]    The positive guidance by which the intermediate plate  122  is tilted in this case is not constituted by a tension element but by a rigid link plate  130  tightly connected to the base  12  (cf.  FIG. 13 ). The intermediate plate  122  therefore goes without the securing tabs of the first embodiment (cf.  FIG. 11 ). 
         [0065]    As in the first embodiment, the belt buckle  20  is connected tightly and rigidly, via the securing openings  24  in the intermediate plate  122 , to the intermediate plate  122 , whereas the latter may tilt along a fixing bolt  28  which extends through the opening  26  in the intermediate plate  122 . The opening  26  and the fixing bolt  28  can be configured as in the first embodiment. 
         [0066]    The link plate  130  is a formed sheet metal part and includes a securing section  148  by which it is tightly connected to the base  12 , for example by a welded connection. Starting from the securing section  148  a guiding section  150  for guiding the intermediate plate  122  extends to a free end  152  facing away from the base  12 . A lower carriage-side end  154  of the intermediate plate  122  constantly abuts on the guiding section  150 . 
         [0067]    The guiding section  160  is tilted against the direction of the tilting movement in the inclined position so that the free end  152  is spaced from the intermediate plate  122  when the latter is upright and is oriented in parallel to the axial direction A. In this example, the guiding section  150  is configured to have a uniform tilt. 
         [0068]    The guiding section  150  is divided into two parallel arms  156  forming a U-shaped cutout and in the completely retracted position encompassing the fixing belt  28 , as this is evident from  FIG. 12 , for example. During the traversing movement, the lower end  154  of the intermediate plate  122  always abuts on both arms  156  to the same extent. 
         [0069]    When the carriage  14  moves along the traversing direction V in the direction of the extended position, the lower end  154  of the intermediate plate  122  slides along the link plate  130 , wherein an increasing range of motion is formed for the intermediate plate  122  along the section  28   a  of the fixing bolt  28 . 
         [0070]    A spring element  142  which, just as the spring element  42  of the first embodiment, in a section  142   a  has plural spiral-shaped windings surrounding the section  28   b  of the fixing bolt  28  in this case includes a free end  142   c  acting as a compression spring which acts on the intermediate plate  122  in the tilting direction N and exerts a force in the inclined position. As in the first embodiment, the free end  142   c  of the spring element  142  encompasses the intermediate plate  122  level with the securing openings  24 . 
         [0071]    The other free end  142   b  of the spring element  142  is tightly anchored to the carriage  14  just as in the first embodiment. 
         [0072]    The  FIGS. 13 to 16  illustrate the movement of the intermediate plate  122  and of the bait buckle  20  during the traversing movement from the completely retracted position without any relative displacement between the carriage  14  and the base  12  (V 0 ) via two intermediate steps (V 1 , V 2 ) shown in  FIGS. 14 and 15  up to the maximally extended position (V max ) in which the belt buckle  20  is tilted about the maximum shift angle α. 
         [0073]    Due to the uniform inclination of the guiding section  160  of the link plate  130 , the tilting movement of the belt buckle  20  is carried out uniformly over the entire shift distance. If the guiding section  150  were configured to have different inclinations in its contour, also a tilting movement of the belt buckle  20  adapted by means of the shift distance could be achieved.