Abstract:
A lock assembly is provided that includes: a lock cylinder having a bore disposed therein and at least one pocket located adjacent the periphery of the bore; a plug including a cassette slot; a plunger that fits in the plug; a locking tab having a slot disposed therein; the slot of the locking tab receives a portion of the plunger; a cassette having a key slot configured to receive a key; the cassette includes a tool slot configured to receive a tool to selectively engage the plunger to selectively move at least a portion of the locking tab into and out of the pocket; when a portion of the locking tab is located in the pocket the locking tab does not block the cassette from being removed from the plug.

Description:
RELATED APPLICATIONS 
       [0001]    This present application is related to and claims priority to U.S. Provisional Patent Application Ser. No. 61/790,503, filed on Mar. 15, 2013, entitled “Removable Key Plug Assembly.” To the extent not included below, the subject matter disclosed in that application is hereby expressly incorporated into the present application. 
     
    
     TECHNICAL FIELD 
       [0002]    The present disclosure relates generally to lock cylinders and particularly to lock cylinders that may be rekeyed. More particularly, the present disclosure relates to a cassette that is removable from the lock cylinder to be rekeyed or repinned. 
       SUMMARY 
       [0003]    The present disclosure relates to a key lock cylinder that includes a cassette configured to receive a key. The cassette fits into a key plug which then fits into the lock cylinder. The cassette is configured to be selectively removable from the plug and a portion of the lock mechanism may be reconfigured so the cassette receives a new key. After rekeying (or repinning) the cassette, it may be reinserted and secured in the plug. The rekeyed (or repinned) cassette will then be able to accept the new key which will be configured to unlock the cylinder and, thus, the latch. 
         [0004]    Another illustrative embodiment of the present disclosure provides a lock assembly comprising: a lock cylinder having a bore disposed therein and at least one pocket located adjacent the periphery of the bore; the cylinder includes a chimney that houses top pins and corresponding springs; a plug including a cassette slot, top opening, and a plunger bore; the plug being held in the lock cylinder by a retaining clip; a plunger fits in the plunger bore of the plug; a locking tab having a slot disposed therein; the slot of the locking tab receives a portion of the plunger; a cassette having a key slot configured to receive a key, and openings configured to receive a plurality of pins that when the key is inserted into the key slot, the pins do not extend beyond a shear line located between the periphery of the lock cylinder bore and its chimney; the cassette includes a tool slot configured to receive a tool for engaging the plunger to selectively move at least a portion of the locking tab to the pocket; when at least the portion of the locking tab is located in the pocket the locking tab does not block the cassette from being removed from the bore in the lock cylinder; and wherein the cassette is available to be rekeyed. 
         [0005]    The above and other illustrative embodiments may include a lock assembly that further comprises: a spring that biases the plunger; and when rotating the plug with respect to the lock cylinder the top pins are prevented from exiting the chimney when the cassette is removed from the plug. 
         [0006]    Another illustrative embodiment of the present disclosure provides a lock assembly comprising: a lock cylinder having a bore disposed therein and at least one pocket located adjacent the periphery of the bore; a plug including a cassette slot; a plunger that fits in the plug; a locking tab having a slot disposed therein; the slot of the locking tab receives a portion of the plunger; a cassette having a key slot configured to receive a key; the cassette includes a tool slot configured to receive a tool to selectively engage the plunger to selectively move at least a portion of the locking tab into and out of the pocket; when a portion of the locking tab is located in the pocket the locking tab does not block the cassette from being removed from the plug. 
         [0007]    The above and other illustrative embodiments may include a lock assembly that further comprises rotating the plug with respect to the lock cylinder preventing the top pins from exiting the lock cylinder when the cassette is removed from the plug. 
         [0008]    Another illustrative embodiment of the present disclosure provides a method for rekeying a lock cylinder comprising the steps of: providing a lock cylinder that receives a plug, and wherein the plug receives a cassette; inserting a key into a key slot in the cassette; rotating the cassette and plug with respect to the lock cylinder; inserting a tool through a tool slot located in the cassette and engaging a plunger located in the plug for moving a locking tab; moving the locking tab to cease it from being a barrier that prevents the cassette from being removed from the plug; and removing the cassette from the plug. 
         [0009]    Additional features and advantages of the removable key cassette assembly will become apparent to those skilled in the art upon consideration of the following detailed description of the illustrated embodiment exemplifying the best mode of carrying out the disclosure as presently perceived. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]    The present disclosure will be described hereafter with reference to the attached drawings which are given as non-limiting examples only, in which: 
           [0011]      FIG. 1  is a partially exploded perspective view of a removable cassette and lock assembly; 
           [0012]      FIG. 2  is a side perspective cross-sectional view of the pin and tumbler cylinder lock assembly with the cassette of  FIG. 1 ; 
           [0013]      FIG. 3  is a perspective exploded view of the removable cassette, pin, and tumbler lock assembly; 
           [0014]      FIGS. 4   a - c  are front, perspective, and perspective cutaway views of the lock assembly; 
           [0015]      FIGS. 5   a - c  are top cross-sectional, front cutaway, and perspective cutaway views of the lock assembly; 
           [0016]      FIGS. 6   a - e  are front, front cutaway, and perspective cutaway views of the lock assembly; 
           [0017]      FIGS. 7   a - d  are perspective cutaway, and with various perspective views of the lock assembly; 
           [0018]      FIGS. 8   a  and  b  are top sectional views of the lock assembly; 
           [0019]      FIGS. 9   a - c  are various perspective and perspective cutaway views of the lock assembly; 
           [0020]      FIGS. 10   a - c  are various perspective cutaway and top cutaway views of the lock assembly; and 
           [0021]      FIGS. 11   a - c  are perspective views of the lock assembly, perspective cross-sectional view of the key in the cassette, and side view of the key in the cassette. 
       
    
    
       [0022]    Corresponding reference characters indicate corresponding parts throughout the several views. The exemplification set out herein illustrates embodiments of the removable key cassette assembly, and such exemplification is not to be construed as limiting the scope of the removable key cassette assembly in any manner 
       DETAILED DESCRIPTION 
       [0023]    A perspective view of removable cassette, pin, and tumbler lock assembly  2  is shown in  FIG. 1 . This view demonstrates how cassette  4  is removable from plug  6  located in cylinder  8 . Using the original key  10  inserted into cassette  4  and resetting tool  12 , cassette  4  is removable from plug  6  allowing cassette  4  to be rekeyed to a new keying configuration. It is appreciated that in this embodiment only cassette  4  is removable, not the entire plug  6 . It is further appreciated that the top pins remain trapped on the chimney as cassette  4  is removed. 
         [0024]    A side perspective cutaway view of lock assembly  2  is shown in  FIG. 2 . This view shows the components fitted in cylinder  8  with key  10  inserted and the pins located in an unlocked position. Chimney  14  houses top pins  16  and springs  17 . It is appreciated that springs  17  bias top pins  16  toward lower pins  18 . When key  10  is properly inserted, the top of lower pins  18  form a shear line  19  with upper pins  16  allowing key  10  to rotate cassette  4  and plug  6  to unlock the door latch. In this embodiment, only lower pins  18  will be removed with cassette  4 . Top pins  16  remain in chimney  14  during the rekeying process. This means the rekeying process is that much simpler. Plug  6  will be rotated to keep top pins  16  in chimney  14 . Lower pins  18  will likewise remain in cassette  4  and removed once cassette  4  is removed from plug  6 . 
         [0025]    A perspective exploded view of lock assembly  2  is shown in  FIG. 3 . This view includes cylinder  8  having a bore  20  disposed therethrough and configured to receive plug  6 . At the periphery of bore  20  are pockets  22  and  24  which assist in the cassette removal process. Chimney  14  is also shown configured to receive top pins  16  and springs  17 . A cap  26  attaches to chimney  14  covering top pin  16  and spring  17 . Plug  6  includes a cassette slot  28  on its face and a longitudinally-extending opening  30  at top. Slot  28  is configured to receive cassette  4  and opening  30  allows communication between bottom pins  18  and top pins  16 . Plug  6  also includes a tool hole  32  configured to receive plunger  34 . Spring  36  engages plunger  34  to move the same longitudinally in directions  38  and  40 . Plunger  34  also communicates with a locking pin  42  which is movable as plunger  34  moves. Clip retainer  44  is configured to engage slots  46  on plug  6  to keep the same held in bore  20  of cylinder  8 . 
         [0026]    The views in  FIGS. 4-10  demonstrate how cassette  4  may be removed from plug  6 .  FIGS. 4   a - c  show the configuration of lock assembly  2  with key slot  48  in a vertical position (see, particularly,  FIG. 4   a ). In this position, cassette  4  cannot be removed. The reason is that tab  42  is not positionable in either pockets  22  or  24  (see  FIGS. 4   b  and  c ). As shown in  FIG. 4   b , pockets  22  and  24  are located at the periphery of bore  20  in cylinder  8 . With key slot  48  in the vertical position, as shown in  FIG. 4   c , tab  42  fits into a recess  50  located in plug  4 . Plunger  34  includes a head  52 , which, as configured as illustratively shown, keeps tab  42  in the position shown. As depicted in  FIG. 4   d , when tab  42  is in this lock position, outside of either pockets  22  or  24 , it blocks cassette  4  preventing it from being movable out of plug  6 . This view also shows how cassette  4  fits into cassette slot  28  of plug  6 . Also shown is head  52  of plunger  34  located in a slot  54  in tab  42  assisting to hold the same in place while key slot  48  is in the shown vertical position (again, see, also,  FIG. 4   a ). 
         [0027]    The views of  FIG. 5   a - c  show further structures in lock assembly  2  while key slot  48  is in the vertical position. As shown in  FIG. 5   a , for example, plunger  34  is shown engaged with spring  36  in bore  56 . Because head  52  of plunger  34  is located in slot  54  of locking tab  42 , plunger  34  cannot move. There is no room for tab  34  to move. As shown, head  52  includes an angled surface which requires slot  54  and tab  42  to be moved in direction  60  in order to move plunger  34 . But as previously discussed with respect to  FIGS. 4   c  and  d , tab  42  cannot move while in its current position. The view in  FIG. 5   a  further demonstrates how tab  42  blocks cassette  4  preventing it from being removable from plug  6 . This view also shows how clip retainer  44  engages slots  46  of plug  6  keeping the same in cylinder  8 . The perspective front view in  FIG. 5   b  further demonstrates how tab  42  is not moveable while key slot  48  is vertical and locking tab  42  is not located in either pockets  22  or  24 . Similarly, the view in  FIG. 5   c  demonstrates how even engaging head  52  of plunger  34  with resetting tool  12  will not move tab  42 . Again, this keeps cassette  4  in plug  6 . 
         [0028]      FIGS. 6   a - e  demonstrate how the structures of lock assembly  2  react when key  10  is rotated to about 45 degrees (see in particular  FIG. 6   a ). As shown in  FIG. 6   b , key slot  48  is now positioned at about 45 degrees from its original vertical position (see  FIG. 4   a ) so locking tab  42  is now able to fit into pocket  22  at the periphery of bore  20  of cylinder  8 . Pocket  22  (or pocket  24  for that matter) provides additional space within which locking tab  42  can move. As shown in  FIGS. 6   c  and  6   d , tab  42  has an available direction of travel  62 , although it has not moved there yet. But once plug  6  is located at the 45 degree angle, resetting tool  12  may be used to push against head  52  of plunger  34  in direction  38 . 
         [0029]    The views shown in  FIGS. 7   a - d  depict what happens when resetting tool  12  pushes and moves plunger  34 . As shown in  FIG. 7   a , for example, pushing resetting tool  12  in direction  38  pushes plunger  34  in direction  38  as well. It is appreciated that head  52  includes an angled edge  64  which serves to slide tab  42  in direction  62  (see also  FIG. 8   a .). By doing this, as shown in  FIG. 7   b , tab  42  moves at least partially in pocket  22  removing it from recess  50 , which, again, is part of cassette  4 . The view in  FIG. 7   c  shows how this occurs when key  10  is also inserted into lock assembly  2 . It is appreciated that cassette  4  may include a plug cover  66  so plunger  34  and other previously described structures are inaccessible exterior of lock assembly  2 . 
         [0030]    The top cross-sectional views in  FIGS. 8   a  and  b  demonstrate how resetting tool  12  moves in direction  38  to move plunger  34  in direction  38  as well which moves tab  42  in direction  62 . In this view, resetting tool  12  inserts into slot  68  in plug cover  66  to access head  52  of plunger  34 . In the isolated view of  FIG. 8   a , the engagement between resetting tool  12  and head  52  is better illustrated. By moving resetting tool  12  in direction  38 , angled surface  64  of head  52  slides tab  42  in direction  62  where there is sufficient space in slot  54  to allow tab  42  to move. Continued movement of resetting tool  12  and plunger  34  continues sliding tab  42  in direction  62  to remove the same from recess  50  of cassette  4 . As this view and the isolated view of plunger  34 , tab  42 , and resetting tool  12  also illustrate, recess  50  fits into slot  54  which means tab  42  has been removed from recess  50 . The isolated view also demonstrates how resetting tool  12  will not push plunger  34  past tab  42 . As shown, head  52  is oriented horizontally with respect to the orientation of resetting tool  12  so that resetting tool  12  cannot move any further past the front face of tab  42 . 
         [0031]    The view shown in  FIGS. 9   a - c  depicts how cassette  4  may be removed from plug  6 . As  FIG. 9   a  demonstrates, because plunger  34  is spring loaded it will begin exiting as well. But as plunger  34  moves, it is configured to block blocking tab  42  preventing the same from sliding back into recess  50  in cassette  4 . The view in  FIG. 9   c  shows the same process at a perspective cutaway angle. It is also appreciated that being temporarily locked in this 45 degree angle, plug  6  is blocking top pins  16  preventing them from dropping out of chimney  14 . Cassette  4  may then be removed from plug  6 , as shown in  FIG. 9   c , without any worry of top pins  16  falling out as well. 
         [0032]      FIGS. 10   a - c  depict cassette  4  being removed from plug  6 . As shown in  FIG. 10   a , cassette  4  may be removed from slot  28  in plug  6 . The same can be seen from the alternate top cross-sectional view of  FIG. 10   c . This view also shows how resetting tool  12  may be configured so cassette  4  may be removed while resetting tool  12  is still engaged with plunger  34 . Lastly,  FIG. 10   b  shows cassette  4  completely removed from slot  28  of plug  6 . This view demonstrates how tab  42  stays out of slot  28  by virtue of plunger  34  so cassette  4  may be reinserted into slot  28  once it has been rekeyed. 
         [0033]    The views shown in  FIGS. 11   a - c  depict how cassette  4  may be rekeyed and then reinserted into plug  6 . For example, the cross-sectional perspective view of  FIG. 11   a  shows a new key  70  in key slot  48 . New bottom pins  72  replace the original bottom pins  18  by removing them from openings  74  at the top of cassette  4 . A side view of this is shown in  FIG. 11   b . Once cassette  4  is rekeyed with new bottom pin,  72 , cassette  4  may be reinserted into slot  28  of plug  6 . Rotating plug  6  45 degrees in the opposite direction and removing rekeying tool  12  will cause the bottom and top pins to reengage and tab  42  to slide back into recess  50  thereby locking cassette  4  in plug  6  again. 
         [0034]    Additional features and advantages of the removable key plug assembly will become apparent to those skilled in the art upon consideration of the following detailed descriptions exemplifying the best mode of carrying out the removable key plug assembly as presently perceived. What is claimed is a removable key plug assembly.