Patent Publication Number: US-7210714-B2

Title: Locking device for a movable carbody part such as a rear hatch of a vehicle

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The invention relates to a locking device for a movable carbody part such as a rear hatch of a vehicle. The locking device comprises a lock and a locking member interacting with the lock; one is mounted on the movable carbody part and the other is mounted on the stationary carbody. The lock has a rotary latch with a pre-catch, a main catch, and a recess. When closing the carbody part, the locking member moves into the recess of the rotary latch and the rotary latch is rotated to a pre-catch position in which a pawl, rotatably supported within the lock and spring-loaded, drops into the pre-catch of the rotary latch. A motor-driven closing aid for the movable carbody part is provided. It comprises two levers that are pivotably supported within the lock wherein the rotary latch is rotated by the motor by means of the levers into the main catch position, in which the pawl is supported on the main catch of the rotary latch. The lock thus comprises a rotary latch, a locking pawl, and a motor-driven closing aid with two levers that are stationarily and rotatably supported in the lock. The levers move the rotary latch from the pre-catch position, into which it has been moved upon closing of the movable carbody part by the locking member, into the main catch position that is secured by the pawl. 
   2. Description of the Related Art 
   A locking device of this kind has already been proposed; see German patent document 103 27 997. In this device, the closing aid comprises in addition to the stationarily supported levers two additional levers of which one is an elbow lever and the other serves as a driver for the rotary latch. These four levers are connected to one another by two additional swivel joints. The closing aid of this device requires many components and therefore also a large space within the lock. 
   SUMMARY OF THE INVENTION 
   It is an object of the present invention to develop a reliable locking device of the aforementioned kind that has only a few components and requires less space. 
   In accordance with the present invention, this is achieved in that the closing aid comprises an active working lever that is swivelled by the motor and comprises a slider block guide (working guide) in which a slider block is guided. The closing aid further comprises a passive control lever with a slider block guide (control guide) in which the same slider block that is guided in the working guide is also guided. The working guide crosses the control guide and the slider block is positioned at the crossing point of the two slider block guides. The slider block has a shoulder and the rotary latch has a counter shoulder. Upon motor-driven pivoting of the working lever, the shoulder hits the counter shoulder and causes the rotary latch to rotate from its pre-catch position into the main catch position. 
   Accordingly, the closing aid is comprised of a working lever that is swivelled by a motor by means of a connection connecting the motor and the working lever. A slider block is guided within the working lever. Moreover, the closing aid comprises a control lever with a control guide in which the same slider block as the one guided in the working lever is guided. Both slider block guides (working guide and control guide) cross one another and the slider block is positioned at all times at the crossing point of the two slider block guides. The slider block has moreover a shoulder that is correlated with a counter shoulder on the rotary latch. When the motor (not shown in detail) actuates the working lever, the shoulder of the slider block hits the counter shoulder of the rotary latch and rotates the rotary latch from its pre-catch position into the main catch position. 

   
     BRIEF DESCRIPTION OF THE DRAWING 
     In the drawing: 
       FIG. 1  shows a lock of the locking device of the present invention that is arranged on the rear hatch of a vehicle and is shown in a position that is reached after the hatch has been partially closed; 
       FIG. 2  shows the lock of  FIG. 1  when the closing aid integrated into the lock is within a first phase of its movement; 
       FIG. 3  shows the lock in a position where the closing aid presses the hatch especially tightly against the stationary carbody part; 
       FIG. 4  shows the locking device after completion of the movement of the closing aid when the rear hatch is in its proper completely closed position; and 
       FIG. 5  shows the action of a manual emergency opening device integrated into the locking device for opening the lock when the motor or its electrical control has failed. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   The locking device according to the present invention is comprised of a lock that, as already stated, is integrated into the rear hatch (not illustrated in detail) of a vehicle and also comprised of a locking member  14  in the form of a bracket that is attached to the stationary carbody of the vehicle. In the plan views of the drawings, not only the components of the lock arranged in the interior of a lock housing are illustrated but also the components of a closing aid cooperating with the lock. The locking member  14  is shown in section so that the cross bar of the bracket is illustrated in cross-hatching. The lock itself comprises the following components. 
   In the lock housing a rotary latch  10  is arranged on a stationary swivel axis  15 . The rotary latch  10  comprises a pre-catch  11  illustrated in  FIG. 1  and a main catch  12  that can be seen in  FIG. 4 . Moreover, the rotary latch  10  has a recess  13 . When the hatch is open, the rotary latch  10 , as illustrated in dash-dotted lines in  FIG. 1 , is in an open position illustrated by the auxiliary line  10 . 0 . This open position  10 . 0  is determined by a stop and, in the illustrated embodiment, also determined by a spring load  17 . When the hatch is closed by hand, the locking member  14  moves into the recess  13 , indicated by the dash-dotted line in  FIG. 1 , and moves the rotary latch  10  from its position  10 . 0  shown in dash-dotted lines into the rotary position indicated by auxiliary line  10 . 1 . Now the locking projection  21  of a pawl  20  can drop into the pre-catch  11  of the rotary latch  10 . Accordingly, the rotary position  10 . 1  of  FIG. 1  is the pre-catch position of the rotary latch  10 . 
   The pawl  20  is mounted on a stationary swivel bearing  25  that is arranged, as already mentioned, within the lock housing (not illustrated) and is subjected to a spring load  27 . The spring load  27  urges the pawl  20  against the rotary latch  10 . When the pre-catch position  10 . 1  of the rotary latch  10  is reached, limit switches and/or sensors ensure that a motor  36 , shown only schematically in  FIG. 1 , is turned on. The limit switches and/or sensors can also respond to the position of the rear hatch in the pre-catch position  10 . 1 . The motor  36  initiates the movement of a closing aid that is of a very simple configuration and comprised only of the following components. 
   There is a working lever  30  that is connected by a connection  32  to the output member of the motor  36 . This working lever  30  is mounted on a stationary swivel bearing  35  in the lock housing. In the illustrated embodiment, a swivel axis of the swivel bearing  35  is identical to the swivel or bearing axis  15  of the rotary latch  10 . The connection  32  can be a rod or a cable of a Bowden cable device that engages the point of activation  33  of the working lever  30 . The motor-driven working lever  30  is the active component of the closing aid. The working lever  30  has also a slider block guide  31 , referred to in the following for short as working guide. The working guide  31  extends substantially radially to the swivel bearing  35  of the working lever  30 . In the working guide  31 , comprised of a linear slotted hole, a slider block  50  configured as a bolt is guided. In the drawings, the front end face of the slider block is shown. The rear of the slider block  50  has a shoulder  56  whose function will be explained in more detail in the following. 
   The closing aid also comprises a control lever  40  that is supported on a stationary swivel bearing  45  in the lock housing. This swivel axis of the swivel bearing  45  is identical to the axis of rotation of the swivel bearing  25  of the pawl  20 . The control lever  40  also has a slider block guide  41  which, for differentiating it from the aforementioned slider block guide  31 , is referred to as control guide and can be seen best in  FIG. 2 . The control guide  41  extends at a slant relative to a radius that is positioned through the swivel axis  35  of the control lever  40 . The control guide  41  can be divided into to guide sections  42  and  44  which differ in regard to their profiling or shape from one another. There is a substantially linear front section  42  that is substantially perpendicular to the aforementioned radius extending through the swivel axis  45  of the control lever  40 . The terminal section  44  of the control guide  41 , however, is arc-shaped. As shown in  FIG. 2 , this terminal section  44  has a circular shape. The center of the circle is positioned substantially on the swivel axis  35  of the neighboring working lever  30  whose swivel axis  35 , as already mentioned, is identical to the axis of rotation  15  of the rotary latch  10 . In the two sections  42 ,  44  of the control guide  41  the same slider block  50  as the slider block that engages the working guide  31  of the working lever  30  is guided. The two slider block guides  31 ,  41  cross one another. The slider block  50  is always positioned at the crossing point  51  of the working guide  31  and the control guide  41  that is shown best in  FIG. 4 . 
   For completing the closing aid, the rotary latch  10  must only be provided with a counter shoulder  16  that interacts with the aforementioned shoulder  56  of the slider block  50  in the way to be described in the following. 
   As already mentioned, the closing aid begins to operate when the pre-catch position  10 . 1  of  FIG. 1  is reached when the hatch is closed. Now the working lever  30  is pivoted by the motor  36  in the direction of arrow  34  until it reaches the intermediate position illustrated in  FIG. 2 . In this intermediate position, the slider block  50  has moved within the working guide  31  as well as within the front section  42  of the control guide  41  to such an extent that the shoulder  56  of the slider block  50  comes to rest against the counter shoulder  16  of the rotary latch  10 . From this moment on, a further actuation of the motor  36  in the direction of arrow  34  causes the working lever  30  to pivot farther into a pivoted position so that the lever  30  entrains in this way the rotary latch  10  by means of the shoulder  56  of the slider block  15  that is also being moved by the lever  30 . Accordingly, the slider block  50  reaches the aforementioned circular arc-shaped terminal section  44  of the control guide  41  where it moves about the swivel axis  50  of the working lever  30  and thus also about the axis of rotation  15  of the rotary latch  10 . As this occurs, the contacting areas of the pawl  20  are pivoted against the force of the spring load  27  acting on it out of the pre-catch  11  by suitable profilings. 
   The motor  36  will stop when the rotary position of the rotary latch  10 , illustrated by the auxiliary line  10 . 3  in  FIG. 3 , is reached. In order for the locking projection  21  of the pawl  20  to drop safely into the main catch  12  as a result of its spring load, the rotary latch  10  has moved a little farther than necessary. In this way, a gap  18  shown in  FIG. 3  is formed between the locking projection  21  of the pawl  20  and the main catch  12  of the rotary latch  10 . Because of this gap  18 , the aforementioned rotary position  10 . 3  is therefore referred to as the overextended position of the rotary latch  10 . 
   The motor  36  can now release the aforementioned connection  32  to the working lever  30  so that the spring load  37  returns the working lever  30  into its initial position shown in  FIG. 1 . This process is illustrated in  FIG. 4  by a return arrow  38 . Alternatively, in the case of a fixed connection  32  to the working lever  30 , the motor  36  can be used to return the working lever  30  into the aforementioned initial position of  FIG. 1  or  FIG. 4 . The slider block  50  then has been moved, starting from  FIG. 3 , first in the terminal section  44  of the control guide  41  and subsequently also within the front section  42  of the control guide  41  as well as in the matching working guide  31  to the opposite end of the slider block guide. Immediately at the beginning of this return movement  38 , the shoulder  56  of the slider block  50  has been lifted off the counter shoulder  16  of the rotary latch  10 . In this way, the rotary latch  10  is rotated because of its spring load  17  to such an extent that its main catch  12  contacts the locking projection  21  of the pawl  20 . The resulting position of the rotary latch  10  is illustrated by the auxiliary line  10 . 2  in  FIG. 4 ; this position is therefore referred to as the main catch position of the rotary latch  10 . As the rotary latch  10  passes from the pre-catch position  10 . 1  of  FIG. 2  through the overextended position  10 . 3  into the main catch position  10 . 2 , the locking member  14  is of course entrained by it. In the main catch position  10 . 2  of  FIG. 4 , the hatch is completely closed. 
   In order to be able to open the hatch, the pawl  20  has an actuation projection  22  for an opening device, not illustrated, which can be operated e.g. by a motor. By means of the opening device, the pawl  20  is rotated in the direction of arrow  26  of  FIG. 4  and the locking projection  21  is thus moved away from the rotary latch  10 . Accordingly, the main catch  12  and the pre-catch  11  are released. The rotary latch  10  can then be returned because of the spring load acting on it into the open position  10 . 0  of  FIG. 1 . Now the locking member  14  is also released and the rear hatch can be opened. 
   The motor-driven closing aid in the locking device of the present intention also makes it possible to open the hatch when the motor  36  or its electric control fails. This will be explained in more detail with the aid of  FIG. 5 . 
   On the control lever  40  there is an engagement location  47  for an emergency actuation device of which in  FIG. 5  only a connection  46  is illustrated. This emergency actuation or emergency opening device and the connection  46  can be manually actuated in the direction of arrow  48 . The result of an actuation in the direction of arrow  48  is that the pawl  40  is moved against its spring load  27  in the direction of arrow  49  of  FIG. 5 . When pivoting in direction of arrow  49 , the slider block  50  moves from the position illustrated in  FIG. 5  into the end portion of the terminal section  44  of the control guide  41 . As already disclosed, the terminal section  44  is a circular segment relative to the swivel axis  35  of the working lever  30  but not relative to the swivel axis  45  of the control lever  40 . When pivoting in the direction of arrow  49 , the slider block  50  reaches the end of the control guide end section  44 . The slider block  50  is now positioned at a greater radial spacing relative to the swivel axis  45  of the control lever  40 . Since the motor  36  according to the assumed scenario has failed, the working lever  30  remains initially in the position illustrated in  FIG. 5  so that the position of the working guide  31  is stable. When pivoting the control lever  40  in the direction of arrow  49 , the slider block  50  that is always positioned at the crossing point  51  of the two slider block guides  31 ,  41  is lifted in the direction of arrow  52  illustrated in  FIG. 5  until the position  50 ′ of the slider block  50  illustrated in dashed lines in  FIG. 5  is reached; this position  50 ′ is referred to as the emergency opening position. In this emergency opening position  50 ′, the slider block  50  is located outside of the reach of the counter shoulder  16  of the rotary latch  10 . Accordingly, upon emergency actuation (arrow  48 ) the rotary latch  10  is released and can be returned in the direction of its spring load  17  into the open position  10 . 0  of  FIG. 1 . The prerequisite for this is that the pawl  20  allows this to happen. This is achieved according to the present invention in the following way. 
   The control lever  40  has a control surface  43  that is aligned with a counter control surface  23  of the pawl  20 . These control and counter control surfaces  43 ,  23  can be in the form of projections or crimped portions of these components  40 ,  20 . Upon pivot movement (arrow  49 ) of the control lever  40  in the emergency situation, the control surface  43  hits the counter control surface  23  and moves the pawl  20  against the spring load  27  in the direction of the already mentioned arrow  24  away from the rotary latch  10 . When the rotation (arrow  24 ) has moved the locking projection  21  out of engagement, the locking projection  21  can no longer drop into one of the catches, for example, into the pre-catch  11 , of the rotary latch  10  when the rotary latch  10  is returned by its own spring load  17  into the pre-catch position  10 . 1  of  FIG. 1 . The hatch is thus open and access to the interior of the vehicle is possible. 
   While specific embodiments of the invention have been shown and described in detail to illustrate the inventive principles, it will be understood that the invention may be embodied otherwise without departing from such principles.