Abstract:
An operating mechanism for a parking brake. The operating mechanism includes a manual brake lever pivotably coupled to a bearing block by a tubular holder. The manual brake lever is fixed to the tubular holder. The mechanism also includes a locking device adapted to fix the manual brake lever in a predetermined pivoting position, an activation rod guided inside the manual brake lever and operatively connected to the locking device, and a transfer element connected to the tubular holder. The transfer element is adapted to transmit movement of the manual lever to the parking brake.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority under 35 U.S.C. §119 to German Patent Application No. 10 2009 022 460.2, filed in Germany on May 23, 2009, the entire subject matter of which is expressly incorporated herein by reference. 
       BACKGROUND OF THE INVENTION 
       [0002]    The invention relates to an operating mechanism for a parking brake. 
         [0003]    An operating mechanism of this type is known from German Document DE 195 21 159 C2. This operating mechanism comprises a manual brake lever which is positioned pivoting in a bearing block. The manual brake lever can be set in various positions for activating the parking brake with the aid of a locking device. The locking device may comprise a locking segment and a detent which can be activated by an activation rod. 
         [0004]    The manual brake lever comprises two lever side parts embodied as shells. On the inside, these shells have formed-on parts which permit the positioning of the locking device as well as the activation rod. A handle that must be fitted onto the shells is furthermore provided as an additional component of the manual brake lever. The activation rod in this case is guided inside a tubular, formed-on part of the shells located in the handle. 
         [0005]    Bearing bushings with a bearing tube guided therein are installed into the shell halves for the manual brake lever. With its longitudinal ends, this bearing tube engages in circular openings in the bearing block, thus allowing a pivoting movement of the manual brake lever on the bearing block. 
         [0006]    The disadvantage of this arrangement is that the operating mechanism comprises a plurality of individual parts which require a relatively involved assembly. 
       SUMMARY OF THE INVENTION 
       [0007]    It is an object of the present invention to provide an operating mechanism of the aforementioned type which has a compact design and can be produced efficiently. 
         [0008]    According to an illustrative embodiment, this object may be solved with an operating mechanism for a parking brake, the operating mechanism comprising: a manual brake lever pivotably coupled to a bearing block by a tubular holder, wherein the manual brake lever is fixed to the tubular holder; a locking device adapted to fix the manual brake lever in a predetermined pivoting position; an activation rod guided inside the manual brake lever and operatively connected to the locking device; and a transfer element connected to the tubular holder, wherein the transfer element is adapted to transmit movement of the manual lever to the parking brake. 
         [0009]    The operating mechanism for a parking brake according to the invention comprises a manual brake lever, which is positioned pivoting on a bearing block and can be locked in place in a predetermined pivoting position with the aid of a locking device. The operating mechanism furthermore comprises an activation rod, guided inside the manual brake lever and operatively connected to the locking device. The pivoting bearing is formed with a tubular holder, which is positioned rotating on the bearing block, is fixedly connected to the manual brake lever and is provided with a transmission element for transmitting the pivoting position of the manual brake lever to the parking brake. 
         [0010]    The inventive operating mechanism includes a low number of individual parts and has a modular configuration that also permits the realization of different variants. 
         [0011]    It is particularly advantageous that the bearing block, the tubular holder and in particular also the manual brake lever are each embodied integrally as one piece, thus permitting a particularly easy and fast assembly of the operating mechanism. 
         [0012]    The tubular holder and the manual brake lever, which can be attached thereto, form an easy to assemble structural unit. It is advantageous that the tubular holder forms a holder for the transmission element which can be embodied as rope or cord, a lever or a rod. The structural unit created by affixing the manual brake lever to the tubular holder thus results in a fixed, spatially unchangeable relationship between the manual brake lever and the transmission element, thereby ensuring that the pivoting movement is transmitted to the transmission element for the operation of the parking brake. 
         [0013]    It is particularly advantageous if the manual brake lever is provided with an opening into which an extension on a longitudinal end of the tubular holder can be pressed. 
         [0014]    The connection created by pressing the tubular holder into the manual brake lever can be created easily and quickly. 
         [0015]    To create this press-fit connection, the edge that delimits the opening of the manual brake lever and the outer surface of the projection function as press-fit surfaces. 
         [0016]    It is particularly advantageous if the press-fit surfaces of the projection and the opening are not radially symmetrical, so that the manual brake lever can be inserted only in a specified, desired position into the tubular holder. 
         [0017]    Owing to this geometric structural guideline, it is avoided that during the production and assembly of the operating mechanism, the manual brake lever is pressed in an incorrect position into the tubular holder. 
         [0018]    According to a particularly advantageous embodiment of the invention, the edge of the manual brake lever opening forms two press-fit surfaces which adjoin in the center of the opening and have mirror-symmetrical inclinations toward the center of the opening, such that the opening diameter increases, starting from the center toward the side edges. 
         [0019]    As a result, the manual brake lever opening can optionally be pressed onto a tubular holder provided with a projection on the right or on the left longitudinal side end. 
         [0020]    With this type of embodiment, it is particularly easy to realize different variants of the operating mechanism. In particular, different operating mechanisms for right-steering or left-steering motor vehicles can thus be produced particularly easily. Depending on whether the operating mechanism is produced for a right-steering or a left-steering motor vehicle, only a specific variant of the tubular holder must be selected for which the matching projection is affixed either on the right end or on the left end. However, the same manual brake lever can be used for both variants since it can optionally be pressed onto either variant of the tubular holder as a result of the two press-fit surfaces. This leads to a considerable reduction in parts for the variants. It is particularly advantageous that the bearing block is embodied such that the same bearing block can be used for both variants, which further reduces the number of parts for realizing the variants. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0021]    These and other features and advantages of the invention will be further understood from the following detailed description of the preferred embodiments with reference to the accompanying drawings, showing in: 
           [0022]      FIG. 1 : A first view of an embodiment of an operating mechanism for a parking brake; 
           [0023]      FIG. 2 : A second view of the operating mechanism shown in  FIG. 2 ; 
           [0024]      FIG. 3 : A partial sectional view of the arrangement shown in  FIG. 2 ; 
           [0025]      FIG. 4 : A detail view of a portion of the manual brake lever and the tubular holder for the operating mechanism according to  FIGS. 1 to 3 ; 
           [0026]      FIG. 5 : A partial representation of the manual brake lever pressed onto the tubular holder, shown as a cross-sectional view. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0027]      FIGS. 1 and 2  show an exemplary embodiment of the operating mechanism  1  according to the invention, which is used for a parking brake on a vehicle and in particular a motor vehicle. 
         [0028]    The operating mechanism  1  is provided with a manual brake lever  2  which is attached pivoting to a bearing block  3 . The bearing block  3  includes at least one cast part, wherein the cast part is preferably composed of a light metal alloy. 
         [0029]    The manual brake lever  2  is embodied integrally and is also embodied as a cast part, wherein this cast part is also composed of a light metal alloy. Aluminum-alloys or magnesium alloys are preferably used for the bearing block  3  as well as for the manual brake lever  2 . The manual brake lever  2  is positioned around a horizontally extending pivoting axis, wherein the manual brake lever  2  is attached to a tubular holder  4  to which a transmission element  5  is also attached. 
         [0030]    The respective position of the manual brake lever  2  is transmitted via this transmission element  5  to the vehicle parking brake which is not shown herein. The transmission element  5  in the present case is embodied as a rope or cord, but can alternatively also be embodied as a cable or a rod. 
         [0031]    The manual brake lever  2  comprises a guide  6  with a displaceable activation rod  7  located inside. In the embodiment shown, the activation rod  7  is a rod-shaped plastic part. The guide  6  is embodied as a U-shaped profile, with its open side exposed on one side of the manual brake lever  2 . By arranging the opening of the U-shaped profile on the side, the activation rod  7  can be inserted from the side into this guide. 
         [0032]    A push button  8  is fitted onto the front end of the activation rod  7 , which projects over the guide  6 , and is secured thereon with the aid of locking means and the like. 
         [0033]    The activation rod  7  is connected to a locking device  9 , wherein this locking device  9  can be used to lock the manual brake lever  2  in a predetermined pivoting position. 
         [0034]    The locking device  9  may comprise a detent  10  and a locking segment  11 . The locking segment  11  is attached to the bearing block  3  and is provided with a strip and detent teeth  12 . 
         [0035]    The detent  10  is positioned on a pivot bearing  13  on the manual brake lever  2 , so as to pivot around a horizontally extending pivoting axis, and is pre-tensioned via a spring element  14 . 
         [0036]    The pivoting axis extends through the center of the detent  10  and divides this detent into pivoting arms extending on both sides of the pivoting axis. The first pivoting arm of the detent  10  is connected to the activation rod  7 . The second pivoting arm of the detent  10  engages in the locking segment  11 . For this, the detent  10  is provided on the front end of the second pivoting arm with a latching nose which can be made to engage into the detent teeth  12  of the locking segment  11 . 
         [0037]    The activation rod  7  is prevented from moving out of the guide with the aid of a guide clip  15  as well as the connection between the detent  10  and the activation rod  7 . 
         [0038]    To release the detent  10  from the locking segment  11 , the push button  8  is depressed. As a result, the activation rod  7  is displaced and the detent  10  released counter to the spring force of the spring element  14  from the locking segment  11 . 
         [0039]    The design and function of the tubular holder  4  can be seen in particular in  FIGS. 2 and 3 . The tubular holder  4 , which may also comprise a light metal alloy in the same way as the manual brake lever  2  and the bearing block  3 , is provided in addition to the hollow-cylindrical basic body  4   a  with a formed-on part  4   b , in which the transmission element  5  in the form of a traction rope is guided and secured. A screw  16  is provided on one end of the formed-on part  4   b  as a means for securing the traction rope. 
         [0040]      FIG. 3  shows that the tubular holder  4  on the inside has an axially extending cavity with a circular cross-section.  FIG. 3  furthermore shows that two bearing bushings  17  are inserted into this cavity. These bearing bushings  17  are secured in their positions on the respective ends of the cavity by horizontal flanges that rest against the longitudinal ends of the tubular holder  4 . A bearing tube  18  is inserted into this cavity which is subsequently inserted and secured in bores in the side walls  3   a  of the bearing block  3 , so that the bearing tube  18  is affixed non-rotating to the bearing block  3 . As a result, the tubular holder  4  with the attached manual brake lever  2  is thus positioned rotating on the positioning tube  18 , wherein a positioning with low friction is achieved when the tubular holder  4  is rotated because of the bearing bushings  17  that glide on the positioning tube  18 . 
         [0041]    The integrally embodied manual brake lever  2  is attached non-rotating in a predetermined desired position by pressing it onto the tubular holder  4 .  FIGS. 4 and 5  in particular show the components on the manual brake lever  2  and the tubular holder  4  which are required for the press-fit connection. 
         [0042]    On one longitudinal end of its basic body  4   a , the tubular holder  4  is provided with a projection  19 , also tube shaped, for which the outer surfaces function as press-fit surfaces. The outer surfaces are provided with bevels, such that the outside diameter of the projection  19  is tapered continuously toward its frontal, exposed end. 
         [0043]    As can be seen in  FIG. 4 , the press-fit surfaces are structured such that in circumferential direction of the projection  19 , four offset-arranged ribs  20   a - d  are provided. These ribs  20   a - d  respectively extend over the total length of the projection  19 , wherein the ribs  20   a - d  have different widths and are arranged at different distances relative to each other. 
         [0044]    The manual brake lever  2  is provided with an opening  21  into which the projection  19  of the tubular holder  4  can be pressed. The contour of the opening  21  is accordingly adapted to the contour of the projection  19 . The opening  21  is provided for this with bulges that correspond to the individual ribs  20   a - d  of the projection  19 . 
         [0045]    Since the ribs  20   a - d  of the projection  19  are not radially symmetric with respect to the rotational axis of the tubular holder  4  (and accordingly also the bulges on the opening  21  of the manual brake lever  2 ), the manual brake lever  2  can be pressed onto the projection  19  of the tubular holder  4  in only the desired position. 
         [0046]    For the press-fit operation, the inner surface of the opening  21  forms two press-fit edge surfaces  22   a ,  22   b . These two edge surfaces  22   a ,  22   b  are slanted relative to each other to form separate press-fit surfaces on each side of the manual brake lever. The edge surfaces  22   a ,  22   b  adjoin in the center of the opening  21  and then extend at an angle, mirror-symmetrical to each other, toward the respective outer edges of the opening  21 . As a result, the diameter of the opening  21  is smallest at the center and increases toward the respective outer edges. 
         [0047]    As a result of the two press-fit surfaces formed by the edge surfaces  22   a ,  22   b , the manual brake lever  2  can be arranged on a tubular holder  4  having the projection  19  located on its right longitudinal end (corresponding to the embodiments shown in  FIGS. 1 to 4 ). In this case, the edge surface  22   a  is used for the press fit connection with the projection  19  of the tubular holder  4 . This variant is used for motor vehicles where the steering wheel is arranged on the left side of the vehicle. The same manual brake lever  2  can also be attached to a tubular holder  4  where the projection  19  is arranged on the left longitudinal end of the tubular holder  4 . In that case, the edge surface  22   b  of the manual brake lever  2  is used for the press fit connection with the projection  19  of the tubular holder  4 . This type of embodiment is used for right-steering motor vehicles. 
         [0048]    It will be understood that the above description of the present invention is susceptible to various modifications, changes and adaptations, and that the same are intended to be comprehended within the meaning and range of equivalents of the appended claims.