Patent Abstract:
In order to enable a turning of a key of a lock cylinder onto a driven member (shaft  36 ) in the lock cylinder only when a proper key is inserted, yet to prohibit the turning in case of an overload, an overload lock is arranged therebetween. The driven member (shaft  36 ) should specifically actuate functions in the vehicle only if the correct key is used. A threshold rotation torque determines the change between the normal and the overload state. In order to improve the lock cylinder, it is furnished that a disengaging lever ( 40 ) is mounted in the cylinder housing ( 30 ) in a pivotable manner ( 42 ) and can be displaced between two pivot positions in a radial plane defined by the longitudinal axis ( 13 ) of the lock cylinder. A locking cam ( 41 ) belonging to the overload lock is arranged on the free end of the disengaging lever ( 40 ). When the disengaging lever pivots, a carrier ( 50 ) pivots in unison, the carrier having a coupling part which engages in a counter coupling part of the cylinder core ( 10 ) during normal function. The disengaging lever ( 40 ) and the carrier ( 50 ) form a common pivot unit. In case of overload, wherein a rotation of the cylinder core force, the carrier ( 50 ) is decoupled from the cylinder core ( 10 ).

Full Description:
BACKGROUND OF THE INVENTION 
     (1) Field of the Invention 
     The invention is directed to a closing cylinder with a cylinder core for insertion of a key for resetting closing followers in the cylinder core from their blocking engagement in a bearing sleeve. The there provided overload blocker is to protect the closing cylinder against damages, in case unauthorized persons perform forced rotations at the cylinder core by way of a break-in tool. The overload blocker responds to a certain limiting torque. In a normal case, at a rotation of the cylinder core by way of a proper key, the torque is transferred to a drive member of the closing cylinder, which drive member performs the desired functions at the vehicle. If however the limiting torque has been surpassed by forced rotations without key, then the overload blocker passes into an overload case, where the torque does not pass to the driven member of the closing cylinder based on internal decoupling. Then no function is performed in the vehicle. The cylinder core together with the bearing sleeve fixed against rotation relative to the cylinder core is idle running. 
     (2) Description of Related Art including information disclosed under 37 CFR 1.97 and 1.98 
     The German patent document DE 38 27418 C2 shows such a closing cylinder. Here the overload blocker comprises a release sleeve with a sliding claw connected in fact axially fixed but rotatable to the release sleeve. The sliding claw has a coupling part, which engages a counter coupling part of the closing cylinder based on a spring force. Profiled locking cams and counter profiled locking recesses are disposed between the release sleeve and a bearing sleeve, wherein the release sleeve is shifted parallel between its normal position and its overload position through the locking recesses. A helical spring encloses a core piece of the driven member and of the sliding claw and takes care of a pressure on all sides between an inner flange of the release sleeve and an outer flange of the sliding claw. Also the sliding claw is shifted parallel thereby during a transition from the normal case to the overload case. 
     The locking cams effective for decoupling the carrier relative to the closing cylinder and the locking recesses between the release member and the bearing sleeve have to be kept small for reasons of space limitations in the known closing cylinder. Therefore various different limiting torques result with a production of the known closing cylinder. The straying of these values makes it more difficult to furnish a guarantee relative to the functional security of the closing cylinder. 
     BRIEF SUMMARY OF THE INVENTION 
     1. Purposes of the Invention 
     It is an object of the present invention to develop a function secured closing cylinder, wherein the overload blocker of the closing cylinder is improved. This is achieved by the following features, which have the following particular importance. 
     2. Brief Description of the Invention 
     The invention employs a release lever, which release lever is swivel supported at its one circumferential position in the cylinder casing, as a release member. The release lever transitions in an axial plane between two swivel positions upon the transition between the normal case and the overload case. The release lever is combined with the carrier to a swivel unit capable of a common swivel motion. The locking cam or, respectively, the locking recess is disposed at a circumferential position, which circumferential position is disposed opposite to the swivel bearing position of the release lever. The swivel bearing position is kept spatially fixed during the transition between the normal case and the overload case, and for that reason more space remains at the oppositely disposed circumferential position. Therefore in case of a predetermined available space in the closing cylinder, the axial height of the locking cam and of the locking recess can be formed larger as with the known, parallel shiftable release member. Based on the larger formation, the production tolerances play a lesser role. Therefore the limiting torque is nearly constant in the context of the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S) 
       Further features and advantages of the invention result from the further claims, the following description and the drawings. An embodiment example of the invention is presented in the drawings. There is shown in: 
         FIG. 1  is a partial longitudinal section of the closing cylinder of the present invention in the normal case of the overload blocker, 
         FIG. 2  is the longitudinal sectional view of the closing cylinder analogous to  FIG. 1  in the overload case of the overload blocker, 
         FIG. 3  is a perspective explosive view showing the components of the closing cylinder of  FIGS. 1 and 2  with a view onto the outer front end of the cylinder core, where only one-half of the cylinder casing is shown, 
         FIG. 4  is a perspective explosive view of the components analogous to the view of  FIG. 3 , however with a view onto the inner end of the device group, 
         FIG. 5  is a perspective view of the device components of the closing cylinder shown in  FIG. 1 , wherein the cylinder casing of the closing cylinder is longitudinally subdivided into two casing shells, of which shells one was dispensed with, and 
         FIG. 6  is a perspective view analogous to  FIG. 5 , where the two casing shells of the cylinder casing are connected to each other. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The closing cylinder comprises initially a cylinder core  10 , which includes a key guide  12  for the insertion of a key not shown in detail. The cylinder core  10  comprises chambers for closing followers not shown in detail, which normally stand in a blocking engagement with a bearing sleeve  20 . The cylinder core  10  is rotatably supported in the bearing sleeve  20 . The lever tumblers are set back through the inserted key, wherewith the cylinder core  10  can be rotated in the bearing sleeve  20  by way of the key. 
     The bearing sleeve  20  is supported axially fixed and rotatable in a cylinder housing  30 , wherein the cylinder housing  30  comprises two housing shells  31 ,  32 . In a normal case however, the bearing sleeve  20  rotatable in the cylinder housing  30  is fixed against rotation through an overload blocker  25 , so long as a torque is exerted onto the cylinder core, where the torque is situated below a predetermined limiting torque. The components of such an overload blocker  25  can be best recognized from  FIG. 4  and they comprise the following device components. 
     The overload blocker  25  comprises initially a release member, which is formed as a release lever  40  in the context of the present invention. The release member namely is pivotably supported at a circumferential position at  42  in the cylinder housing  30 , as is shown in  FIGS. 1 and 2 . The release member has a locking cam  41  disposed opposite to this swivel bearing position  42 , wherein the locking cam  41  tends to engage a snap in recess  21  at the inner front end  22  of the bearing sleeve  20  based on an axial spring loading  16  directed in the direction of the dash-dotted longitudinal axis  13 . The release lever  40  is always non-rotatable positioned in the bearing housing  30  in the way to be described in more detail, therefore also the bearing sleeve  20  is non-rotatable in the normal case by the engagement of the locking cam  41  in the snap in recess  21 . 
     In the normal case, where the overload blocker  25  is effective, therefore a rotation of the inserted key can be transferred from the cylinder core  10  to a driven member  35 , which driven member  35  is rotatably supported at the inner end of the housing  30  as shown in  FIGS. 1 and 2 . A rotation of the driven member  35  is transferred over the shaft  36  connected to the driven member  35  to a function member in the vehicle, for example a vehicle lock in order to perform there the desired functioning in the vehicle. 
     The cylinder core  10  has a staggered cylinder inner end  14  best recognizable from  FIG. 4  for the transition of the rotation, which cylinder inner end  14  is coupled to a carrier  50  in the normal case. This coupling comprises a coupling part  51 , wherein the coupling part  51  is engaged with a counter coupling part  11  of the cylinder core  10  in a normal case. The coupling part is formed by a radial projection  51  according to the embodiment example of the invention, wherein the radial projection  51  points into the interior  52  of the ring of the carrier  50  formed here as a circular ring as can be best recognized from  FIG. 3 . The counter coupling part comprises an axial groove  11  in the staggered cylinder inner end  14  as can be recognized best from  FIG. 4 . The carrier  50  rests at the release lever  40 , wherein the release lever  40  itself is formed as a circular ring. The circular ring of the carrier  50  has initially an axial flange  53  directed toward the outside as can be best recognized from  FIG. 3 , wherein the axial flange  53  in the mounted case rests at the circular ring from the release lever  40 , as is shown in  FIGS. 1 and 2 . A radial collar  54  also exists at the axial flange  53  of the carrier  50 , of the circular release lever recognizable from  FIG. 3 . 
     The rotation of the carrier  50  effected by the rotation of the key in a normal case is transferred to the driven member  35  through two connection means  57 , 37  standing always in engagement to each other. The carrier  50  has three webs  57  disposed parallel to the longitudinal axis  13  as a first connection means, wherein the webs  57  project at the inner front face from the annular body of the carrier  50 . The second connection means comprise holes  37  running parallel to the axis in the driven member  35  as shown in  FIG. 3 . The webs  57  engage in the holes  37  of the driven member  35  not only in the normal case, but also in the overload case in the present situation. 
     The driven member  35  strives to pass into a defined zero position relative to the cylinder housing  30  by way of a so-called pulse spring  26 , which can be recognized in  FIGS. 1 and 2 . For this purpose the pulse spring  26  has two legs  27 ,  28 , which legs grip between themselves on the one hand an axial finger  38  of the driven member  35  and on the other hand a web  33  recognizable best in  FIG. 6 . After rotation of the key, which is only possible in the normal case, therefore the driven member moves back again into its starting rotary position and thereby takes also the cylinder core  10  into a corresponding zero position. 
     The hook piece  44  radially grips around the circular ring of the carrier  50  in the circumferential region and grips behind the circular ring in the assembly situation at its inner front face  56  as shown in  FIG. 1 . Thus there is generated from the release lever  40  and the carrier  50  a common swivel movable unit  55 . However, the carrier  50  is rotatable relative to the release lever  40  in this swivel unit  55  as was mentioned above. 
     The release lever  40  and therewith the complete swivel unit  55  is held in a first swivel position in a normal case as recognizable from  FIG. 1 , wherein the first swivel position is marked by an auxiliary line  40 . 1 . Then the already recited coupling between the locking cam  41  and the snap in recess  21  is present. This first swivel position can therefore be designated as “coupling swivel position”. A connection fixed in axial direction exists between the release lever  40  and the carrier  50 , wherein the connection fixed in axial direction consists of a hook piece  44 . 
     The swivel axis  45  disposed at the swivel bearing position  42  is placed perpendicular to the release lever  40  and at a radial distance from the longitudinal axis  13  of the closing cylinder as is shown  FIGS. 1 and 2 . A bearing piece  46  is inserted in a radial sparing  34  of the cylinder housing  30  and serves for swivel support. The incorporation position of the bearing piece  46  is secured in the sparing  34  by the circumferential face of the bearing sleeve  20  as is shown in  FIGS. 1 and 2 . This alleviates the assembly of the closing cylinder according to the present invention. 
     In addition to the already recited locking cam  41  also a guide piece  48  is disposed opposite to the swivel bearing position  42  that is at the free arm end  47  of the release lever  40  shown in  FIG. 4 . This guide piece  48  engages into an inner recess  39  of the cylinder housing  30  in the assembly case recognizable in  FIGS. 1 and 2 . The guide piece  48  and the housing recess  39  take care of swivel guiding during swiveling of the release lever  40 . The already recited fixed against rotation, but swivel movable guiding of the release lever  40  is obtained in the cylinder housing  30  both through the guide please  48  as well as through the swivel axis  45  at the bearing piece  46 . 
     The previously described axial spring loading  16  attacks only at the arm end  47  of the release lever  40 . For this purpose serves a pressure spring  15 , which according to  FIG. 1  is disposed in the previously recited inner recess  39  in the housing  30 . The pressure spring  15  is supported on the one hand at the inner axial end of the recess  39  in the housing  30  and on the other hand at the support position  17  at the free end  47  of the arm of the release lever  40  as can be best seen in  FIG. 4 . This support position  17  is integrated into the previously recited guide piece  48 . There a receptacle  18  is placed as shown in  FIG. 4 , which receptacle  18  receives at least a part piece of the pressure spring  15 . The receiver  18  can continue in part also in the hook piece  44 . The guide piece  48  is a nose, which is disposed in the circumferential region of the annular body of the release lever  40  and which projects perpendicular to a certain lever plane determined by the annular body of the release lever  40 . The locking cam  41  is formed also at a nose generated by the guide piece  48 , wherein the locking cam  41  belongs to the overload blocker. The hook piece  44  is also disposed in the region of the nose, however the hook piece  44  runs in an opposite direction to the locking cam  41 . 
     An overload case is present were a torque is exerted on the cylinder core through break in tools and the like, wherein said torque amounts to more than the above recited limiting torque. The locking cam  41  and/or the locking recess  21  are in fact axially profiled, whereby run on bevels are generated between them. If the key is not plugged into the cylinder core, then the closing followers not shown in detail in the cylinder core  10  are engaged with the blocking grooves of the bearing sleeve  20 . Then the cylinder core  10  is connected to the bearing sleeve  20  fixed against rotation, whereby the two device components  10 ,  20  are rotated together in the cylinder housing  30  with the break-in tools. Here the run on inclinations take care that the locking cam  41  becomes pressed out of the locking recess  21  against the spring loading  16 . The free end  47  of the arm of the release lever  40  is transferred from a coupling swivel position  40 . 1  of  FIG. 1  into a second swivel position  40 . 2  in  FIG. 2  illustrated by the auxiliary line  40 . 2 , since the release lever  40  with its locking cam  41  is moved over the run on inclinations of the locking recess  21  of the bearing sleeve  20 . The second swivel position  40 . 2  therefore is the decoupling swivel position of the release lever  40 . 
     The carrier  50  is given together in the decoupling swivel position  40 . 2  because of the swivel unit  55 , with the consequence that the coupling  51  of the carrier  50  is decoupled off the counter coupling part  11  of the cylinder part  10 . Therefore, a forced rotation of the cylinder core  10  in case of overload cannot any longer be transferred over the carrier  50  onto the driven member  35 . In face of an overload the cylinder core rotates and the therewith fixed against rotation, bearing sleeve  20  in an idle motion relative to the decoupled swivel unit  55 . The driven member  35  remains in a rest position. No functions in the vehicle can be triggered by the forced rotation of the cylinder core. 
     The angle of the key rotation of the cylinder core  10  is limited by limit stops  23 ,  24  at the driven member  35  in the present case, which can be recognized in  FIG. 3 . These limit stops  23 ,  24  are formed by the inner shoulders of a radial cutout  29  in a circumferential region of the driven member  35 . An axial extension arm  19  is coordinated to this cutout  29  as can be recognized in  FIG. 4 , wherein the axial extension arm is seated at the housing  30 . The inner radial recess  39  of the housing  30  for the guide piece  48  is disposed in part below the axial extension arm  19 . 
     LIST OF REFERENCE CHARACTERS 
     
         
           10  cylinder core 
           11  counter coupling part; axial groove in  13  ( FIG. 4 ) 
           12  key guide ( FIG. 3 ) 
           13  longitudinal axis 
           14  inner end of cylinder of  10  (FIGS.  3 , 4 ) 
           15  pressure spring of  25  ( FIG. 4 ) 
           16  elastic force of  40 , 55 , spring loading ( FIG. 2 ) 
           17  support position for  15  ( FIG. 4 ) 
           18  receiver for  15  in  48  ( FIG. 4 ) 
           19  axial extension arm at  30  ( FIG. 4 ) 
           20  bearing sleeve 
           21  snap in recess in  20   
           22  inner front end of  20  ( FIG. 4 ) 
           23  first limit stop of  35  for  19  ( FIG. 3 ) 
           24  second limit stop of  35  for  19  ( FIG. 3 ) 
           25  overload blocker ( FIG. 4 ) 
           26  pulse spring for  35   
           27  first leg of  26   
           28  second leg of  26   
           29  radial cutout in  25  ( FIG. 3 ) 
           30  cylinder housing 
           31  first housing shell of  30   
           32  second housing shell of  30  ( FIG. 6 ) 
           33  axial web at  30  ( FIG. 6 ) 
           34  sparing for  46  in  30  (FIGS.  1 , 2 ) 
           35  driven member 
           36  shaft at  35  (FIGS.  1 , 2 ) 
           37  second connecting means at  35 , hole ( FIG. 3 ) 
           38  axial finger at  35  for  27 ,  28  (FIGS.  1 , 6 ) 
           39  inner recess in  30  for  48  (FIGS.  1 , 2 ) 
           40  release lever 
           40 . 1  coupling swivel position of  40   
           40 . 2  decoupling swivel position of  40   
           41  locking cam at  40   
           42  first circumferential position of  40 , swivel bearing position 
           43  anullar opening in  40  ( FIG. 3 ) 
           44  hook piece at  40  ( FIG. 4 ) 
           45  swivel axis between  42 ,  40  (FIGS.  1 , 2 , 4 ) 
           46  bearing piece  44  (FIGS.  1 , 2 , 4 ) 
           47  free arm end of  40  (FIGS.  2 , 4 ) 
           48  guide piece at  40  (FIGS.  1 , 2 , 4 ) 
           50  carrier 
           51  coupling part, radial projection 
           52  ring interior of  50 , ring opening ( FIG. 3 ) 
           53  axial flange of  50  ( FIG. 3 ) 
           54  radial collar of  50  ( FIG. 3 ) 
           55  swivel unit out all  40 ,  50  (FIGS.  1 , 2 ) 
           56  inner front face of  50  (FIGS.  1 , 4 ) 
           57  first connecting means at  50 , web

Technology Classification (CPC): 8