Abstract:
An operating mechanism for a parking brake includes a manual brake lever pivotably coupled to a bearing block, a locking device adapted to secure the manual brake lever in a predetermined pivoting position, an actuating rod guided inside the manual brake lever and operatively connected to the locking device, and a guiding device for the actuating rod located on the manual brake lever. The guiding device comprises a U-shaped profile having an opening oriented toward a side of the manual brake lever. The opening is adapted to receive the actuating rod.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority under 35 U.S.C. §119 to German Patent Application No. 10 2009 022 296.0, filed in Germany on May 22, 2009, and German Patent Application No. 10 2009 022 461.0, filed in Germany on May 23, 2009. The entire subject matter of the foregoing two applications is expressly incorporated herein by reference. 
       BACKGROUND OF THE INVENTION 
       [0002]    The present 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 on a bearing block. The parking brake is operated with the aid of an actuating rod which engages in a locking device. The locking device comprises a locking segment and a detent. The locking segment is attached to the bearing block and comprises a bar with latching teeth. The detent is positioned pivoting on a bearing pivot belonging to the manual brake lever and is pre-tensioned via a spring element. A push button is provided on the front end of the actuating rod, wherein this button projects over the tubular holder and can be depressed by an operator. 
         [0004]    The manual brake lever must be pivoted in order to operate the parking brake, wherein this pivoting movement is transmitted via the actuating rod to the detent. In one end position, the detent engages in the locking segment and thus secures the manual brake lever in the respective position. 
         [0005]    The push button is depressed to disengage the manual brake lever from this position, thereby releasing the detent from the locking segment. The manual brake lever can thus be returned once more to the starting position. 
         [0006]    The manual brake lever consists of two shell halves which are closed on the tops by a cover panel. The shell halves are each provided with a semi-circular attachment for accommodating the actuating rod. These attachments when combined form a tubular holder into which the front portion of the actuating rod is inserted. The back portion of the actuating rod, which extends at an angle relative to the front portion, is connected to the detent of the actuating rod. 
         [0007]    The shell halves for the manual brake lever advantageously consist of a light-metal casting alloy. The manual brake lever thus has a high stability but also an undesirably high weight because of its solid, multi-part construction. 
         [0008]    A further disadvantage is the undesirably high cost for producing the multi-part manual brake lever. In addition, the assembly of an operating mechanism provided with a manual brake lever of this type is undesirably complicated. The actuating rod must be inserted into an extension on a shell half before the shell halves are combined, and the actuating rod must furthermore also be joined articulated to the detent. Finally, the shell halves must be joined and the cover panel placed onto the shell halves. 
       SUMMARY OF THE INVENTION 
       [0009]    It is an object of the present invention to design an operating mechanism of the aforementioned type in such a way that it has the highest possible stability with the lowest possible weight as well as low production costs. 
         [0010]    According to an embodiment, an operating mechanism for a parking brake comprises: a manual brake lever pivotably coupled to a bearing block; a locking device adapted to secure the manual brake lever in a predetermined pivoting position; an actuating rod guided inside the manual brake lever and operatively connected to the locking device; and a guiding device for the actuating rod located on the manual brake lever, wherein the guiding device comprises a U-shaped profile having an opening oriented toward a side of the manual brake lever, the opening adapted to receive the actuating rod. According to another embodiment, an operating mechanism for a parking brake comprises: a manual brake lever pivotably coupled to a bearing block; a locking device adapted to secure the manual brake lever in a predetermined pivoting position; an actuating rod guided inside the manual brake lever and operatively connected to the locking device; a guiding device for the actuating rod located on the manual brake lever, wherein the actuating rod is displaceable within the guiding device; and at least one position-securing member adapted to prevent the actuating rod from moving out of the guiding device, wherein the at least one position-securing member comprises a guide clip adapted to connect to the guiding device, wherein the guide clip forms a sliding guide for the actuating rod. 
         [0011]    The operating mechanism for a parking brake according to the invention is provided with a manual brake lever that is positioned pivoting on a bearing block. With the aid of a locking device, the manual brake lever can be secured in a predetermined pivoting position. The operating mechanism according to the invention is furthermore provided with an actuating rod that is guided inside the manual brake lever and is operatively connected to the locking device. The manual brake lever comprises a guiding device in which the actuating rod is positioned so as to be displaceable in the longitudinal direction. The guiding device can be embodied as a U-shaped profile with an opening located on the side of the manual brake lever into which the actuating rod can be inserted. 
         [0012]    A first advantage of the operating mechanism according to the invention is that by embodying the guiding device as a U-shaped profile, the weight of the manual brake lever can be kept low. 
         [0013]    A further advantage of the operating mechanism according to the invention is that by inserting the actuating rod from the side into the guiding device, it can be installed easily and quickly. 
         [0014]    The easy installation of the actuating rod is furthermore aided by the fact that the actuating rod can easily be prevented from moving out of the guiding device by using position-securing means, wherein it is particularly advantageous that the position-securing means can be made available without high cost and structural expenditure. 
         [0015]    According to the invention, a first position-securing means may take the form of a guide clip which can be attached to the guiding device to form a sliding guide for the actuating rod. The guide clip is clipped into or snapped into the guiding device, thereby making it easy to install the clip without tools on the guiding device. 
         [0016]    It is particularly advantageous if the guide clip is provided with a projection which rests flat on the actuating rod if the guide clip is attached to the guiding device. 
         [0017]    A projection of this type makes it particularly easy to compensate for any play between the guide clip and actuating rod. In particular, it is also possible to achieve a reduction in noise during the guiding of the actuating rod inside the guiding device. 
         [0018]    The locking device is provided with a locking segment that is attached to the bearing block as well as a movably positioned detent. The detent is joined articulated to the back end of the actuating rod positioned inside the guiding device. 
         [0019]    The back end of the guiding device is provided with a receptacle in which a segment of the detent is positioned pivoting in order to form an articulated connection. End stops are provided on the receptacle which function as second position-securing means and ensure that the detent segment does not move out of the receptacle. 
         [0020]    Since the detent itself is positioned on the manual brake lever so as to be movable, while also being secured against slipping out, the end stops on the receptacle prevent the actuating rod from slipping out of the guiding device. 
         [0021]    While the second position-securing means embodied in this way is provided on the back end of the guiding device, the first position-securing means formed by the guide clip is arranged advantageously on the front end of the guiding device, so that the actuating rod is held securely and over its total length inside the U-shaped profile of the guiding device. It is particularly advantageous in this case that no additional elements are required, e.g. guiding sleeves for guiding and for securing the actuating rod. 
         [0022]    In the simplest case, the guiding device for the manual brake lever is embodied to extend over its total length along a straight line, which means that the actuating rods can also extend along a straight line. No additional guiding means need to be provided in that case for the sliding guidance of the actuating rod inside the guiding device. 
         [0023]    However, due to requirements resulting from a limited installation space for the operating mechanism within the vehicle, it may be necessary for the guiding device to comprise two parts that each extend along a straight line, but are arranged at an angle relative to each other. 
         [0024]    The shape of the actuating rod is correspondingly adapted to the shape of the guiding device. 
         [0025]    To obtain a perfect guidance of the actuating rod inside the guiding device even with these complex geometries, a pin is provided on the actuating rod as a means for guiding this rod inside the guiding device, wherein this pin moves inside an elongated hole in the guiding device. 
         [0026]    As an alternative, the pin as guiding means for guiding the actuating rod inside the guiding device can move inside an elongated hole that is provided on the actuating rod itself. 
         [0027]    Guiding means embodied in this way can be produced easily and cheaply and will securely prevent a tilting of the actuating rod inside the guiding device. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0028]    The present invention may be more readily understood from the following detailed description when read in conjunction with the accompanying drawings, in which: 
           [0029]      FIG. 1 : A first view from the side of an exemplary embodiment of the operating mechanism for a parking brake according to the present invention; 
           [0030]      FIG. 2 : A second view from the side of a section of the operating mechanism according to the present invention as shown in  FIG. 1 ; 
           [0031]      FIG. 3 : A cross section through a guiding device for a manual brake lever with therein guided actuating rod; 
           [0032]      FIG. 4 : A detailed view of a receptacle for an actuating rod for the operating mechanism according to  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0033]      FIGS. 1 and 2  illustrate an exemplary embodiment of the operating mechanism  1  according to the invention for a vehicle parking brake. 
         [0034]    The operating mechanism  1  is provided with a manual brake lever  2  which is positioned pivoting on a bearing block  3 . The bearing block  3  is a cast part that is preferably composed of a light-weight metal alloy. 
         [0035]    The manual brake lever  2  is furthermore also cast as one piece and is also composed of a light-weight metal alloy. Aluminum or magnesium alloys are preferably used for the bearing block  3  as well as for the manual lever  2 . The manual lever  2  is positioned so as to pivot around a horizontally extending pivoting axis, wherein the manual brake lever is attached to a pivot bearing  4  to which a cord  5  is attached. 
         [0036]    The respective position of the manual lever  2  is transmitted via this cord  5  to the vehicle parking brake which is not shown herein, wherein this cord  5  here also comprises similar elements, such as cables or rods. 
         [0037]    The manual brake lever  2  is provided with a guiding device  6  with therein positioned displaceable actuating rod  7  which in the present case is a rod-shaped plastic part. 
         [0038]    In particular  FIG. 1  and the cross-sectional representation of the guiding device  6  with therein disposed actuating rod  7  show that the guiding device  6  is embodied in the form of a U-shaped profile with an exposed opening on one side of the manual brake lever  2 . As a result of arranging the opening of the U-shaped profile on the side, the actuating rod  7  can be inserted from the side into this guiding device. 
         [0039]    To achieve the most compact design possible for the operating mechanism  1 , the guiding device  6  does not extend along a straight line. Rather, the guiding device  6  has an angled design and is formed by two straight segments which converge at an obtuse angle. In the area of transition, the guiding device  6  has a somewhat curved shape to which the geometry of the actuating rod  7  is adapted. 
         [0040]    In particular  FIGS. 1 and 2  illustrate that a push button  8  is arranged on the front end of the actuating rod  7  and projects over the front end of the guiding device  6  where it can be secured with the aid of locking means and the like. 
         [0041]    The actuating rod  7  is connected to a locking device  9 . With the aid of this locking device  9 , the manual brake lever  2  can be secured in a predetermined pivoting position. 
         [0042]    The locking device  9  essentially comprises a detent  10  and a locking segment  11 . The locking segment  11  is attached to the bearing block  3  and contains a bar with latching teeth  12 . 
         [0043]    The detent  10  is positioned on a manual brake lever  2  so as to pivot around a horizontally extending pivoting axis with the aid of a bearing pivot  13  and is pre-tensioned via a spring element  14 . 
         [0044]    The pivoting axis extends through the center of the detent  10 , thereby dividing it into two pivoting arms that extend on either side of the pivoting axis. The first pivoting arm of the detent  10  is connected to the actuating rod  7 . The second pivoting arm of the detent  10  engages in the locking segment  11 . The detent  10  is provided for this with a latching nose at the front end of the second pivoting arm which can engage in the latching teeth  12  of the detent  11 . 
         [0045]    The push button  8  is depressed to release the detent  10  from the locking segment  11 . As a result, the actuating rod  7  is displaced and the detent  10  is released counter to the spring force of the spring element  14  from the locking segment  11 . 
         [0046]    At the upper end of the first pivoting arm the detent  10  is provided with a segment  15  which serves as connection to the actuating rod  7 . 
         [0047]    The segment  15  is essentially shaped like a circular disc segment and forms a cross-sectional expansion at the front end of the first pivoting arm for the detent  10 . 
         [0048]    The segment  15  is positioned pivoting inside a receptacle  16 , wherein the receptacle  16  forms the back end of the actuating rod  7 . The receptacle  16  takes the form of a half shell that encloses the segment  15 .  FIG. 4  shows an individual representation of the receptacle  16  with view of the open half shell. The segment  15  is positioned with some play inside the receptacle  16 , so that the receptacle  16  can compensate for the play between the detent  10  and the actuating rod  7 . 
         [0049]    End stops  17 , which are arranged offset, are furthermore provided on opposite sides of the receptacle  16  and prevent the segment  15  of the detent  10  from sliding out of the receptacle  16 . Since the detent  10  is arranged pivoting but not detachable on the manual brake lever  2 , these end stops  17  form position-securing means that prevent the actuating rod  7  from moving out of the guiding device. 
         [0050]    A guide clip  18  is provided as a further position-securing means in the region of the front end of the actuating rod  7 . The guide clip  18  is snapped into the guiding device  6  and thus forms a sliding guide for the actuating rod  7  which is guided inside the guiding device  6 . Owing to this guide clip  18 , the actuating rod  7  is secured on its front end to prevent it from moving out of the guiding device  6 . The guide clip  18  preferably consists of a plastic part. 
         [0051]      FIG. 1  shows that the guide clip  18  is provided with a projection  18   a  which sits sliding on the actuating rod  7  if the guide clip  18  is snapped into the guiding device  6 . For one thing, the guide clip  18  compensates for the play between vehicle and guide clip  18  as well as actuating rod  7 , wherein this simultaneously also results in a significant reduction in noise during the operation of the operating mechanism  1 . 
         [0052]    Since the guiding device  6  does not extend along a straight line, but is embodied at an angle and the shape of the actuating rod  7  is adapted thereto, irregularities can occur during the activation of the push button  8 , in particular in the form of a tilting of the actuating rod  7  inside the guiding device  6 . 
         [0053]      FIG. 2 , in particular, shows that suitable guiding means are provided on the actuating rod  7  and the guiding device  6  to avoid this problem. The guiding means in the present case include a pin  19 , which ends on the side of the actuating rod  7 , and an elongated hole  20  in the guiding device, wherein the pin  19  moves inside the elongated hole  20 . 
         [0054]    Alternatively, it is also possible to provide the pin  19  on the guiding device  6  and to provide the elongated hole  20  in the actuating rod  7 . 
         [0055]    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.