Patent Abstract:
A lock actuation assembly for use in a lock chassis. The lock actuation assembly comprises a core and a driver. The core includes a tubular portion positionable in the lock chassis and including a passage therethrough. A flange extends through the tubular portion and is biasable to a position in which a driver engaging portion is within the passage and a projection engaging portion is within the tubular portion&#39;s extent. The driver includes a shaft configured to be received within the passage to operably engage the lock chassis&#39; drive system and to engage the flange driver engaging portion such that the projection engaging portion is forced into engagement with a projection extending into the lock chassis core-receiving chamber.

Full Description:
BACKGROUND  
         [0001]    The present invention relates to lock chassis assemblies and more particularly to a disposable lock actuator assembly.  
           [0002]    During a construction project, doors and related hardware are typically installed prior to completion of the project. The door hardware typically includes a lock set including a lock chassis adapted to receive an interchangeable, key-operated core. During the construction phase, some of the doors, for example perimeter doors and doors to storage areas, may require a key-operated core such that passage through the doors can be limited to individuals having the appropriate key. After the construction phase, these key-operated cores are typically “changed out” such that the building occupants receive new key sets, thereby reducing the risk of unauthorized access by individuals with unaccounted for keys.  
           [0003]    The remaining doors, for example, most interior doors, do not require restricted passage. As such, key-operated cores in these doors are undesirable due to change out cost and the unnecessary restriction on free passage. However, some door actuation means is necessary to allow operation of the lock set, i.e., to allow opening of closed doors. To accommodate such, it is known to provide disposable lock actuators that are insertable into the lock chassis and operable without core specific keys. For example, see U.S. Pat. No. 4,843,852 to Foshee et al.  
         SUMMARY  
         [0004]    The present invention provides a lock actuation assembly for use in a lock chassis having a core-receiving chamber, a lug projection extending into the chamber, and a lock chassis drive system extending into the chamber. The lock actuation assembly comprises core and a driver. The core includes a front plate, a tubular portion and a flange. The front plate is configured to be received in and substantially close the chamber apart from a driver-receiving bore therethrough. The tubular portion extends rearwardly from the front plate co-axially with the bore such that the tubular portion and the bore define a passage alignable with the lock chassis drive system. The tubular portion is configured such that its outer extent can be received in the chamber without interfering with the projection. The flange extends inwardly through the tubular portion and includes a driver engaging portion and a projection engaging portion. The flange is biasable to a position in which the driver engaging portion is within the passage and the projection engaging portion is within the tubular portion&#39;s extents. The driver includes a shaft configured to be received within the passage to operably engage the lock chassis drive system and to engage the flange driver engaging portion such that the projection engaging portion is forced outwardly beyond the tubular portion extents and into engagement with the projection. The driver has a shape complementary to that of the passage such that it easily aligns with the lock chassis drive system. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0005]    [0005]FIG. 1 is an isometric, cross-sectional view of an illustrative lock chassis;  
         [0006]    [0006]FIG. 2 is an exploded isometric view of the lock actuation assembly of the preferred embodiment of the present invention positioned for insertion into a lock chassis;  
         [0007]    [0007]FIG. 3 is a front elevation view of the preferred core member of the present invention;  
         [0008]    [0008]FIG. 4 is a plan view of the preferred core member in the direction of lines  4 - 4  in FIG. 3;  
         [0009]    [0009]FIG. 5 is a cross-sectional view along the line  5 - 5  in FIG. 3;  
         [0010]    [0010]FIG. 6 is a cross-sectional view along the line  6 - 6  in FIG. 4;  
         [0011]    [0011]FIG. 7 is a rear elevation view of the preferred driver of the present invention;  
         [0012]    [0012]FIG. 8 is a cross-sectional view along the line  8 - 8  in FIG. 7;  
         [0013]    [0013]FIG. 9 is a front elevation view of the preferred driver of the present invention;  
         [0014]    [0014]FIGS. 10, 13 and  16  are sectional views of the lock chassis and inserted core along the line  10 - 10  in FIG. 2 with the driver illustrated at various progressions of insertion;  
         [0015]    [0015]FIGS. 11, 14 and  17  are sectional views of the lock chassis and inserted core along the line  11 - 11  in FIG. 10 with the driver illustrated at progressions corresponding respectively to those of FIGS. 10, 13 and  16 ;  
         [0016]    [0016]FIGS. 12, 15 and  18  are sectional views of the lock chassis and inserted core along the line  12 - 12  in FIG. 10 with the driver illustrated at progressions corresponding respectively to those of FIGS. 10, 13 and  16 . 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0017]    The preferred embodiments of the present invention will be described with reference to the drawing figures wherein like numerals represent like elements throughout. Certain terminology, for example, “right”, “left”, “front”, “frontward”, “rear” and “rearward”, is used in the following description for relative descriptive clarity only and is not intended to be limiting.  
         [0018]    Referring to FIGS. 1 and 2, an illustrative lock chassis  10  will be described. The lock chassis  10  includes a cylinder  12  with an aperture  14  through its front face  16  to a core-receiving chamber  18 . In the illustrated lock chassis  10 , the aperture  14  has a “FIG. 8” configuration as this is the standard core configuration, however, other configurations may be utilized. A lock drive system  20  extends into the rear of the chamber  18 . The standard lock drive system  20  includes pins  22  extending from a cam  24  which is in turn to a lock throw  26 . Manipulation of the pins  22  is translated to the lock throw  26  to operate the lock set (not shown). The lock chassis  10  includes one or more control lug projections  26  extending into the core-receiving chamber  18  adjacent the aperture  14 . The lug control projection  26  is a standard means of maintaining the permanent keyed core in the lock chassis  10 . The permanent keyed core is positioned in the chamber  18  and then a designated key is used to extend a lug from the core which contacts the lug projection and maintains the core in position.  
         [0019]    The preferred lock actuation  40  assembly of the present invention will be described with reference to FIGS.  2 - 9 . The lock actuation assembly  40  generally comprises a core  50  and a driver  100 . Referring to FIGS.  2 - 6 , the core  50  includes a front plate  52  which is configured to be received in and substantially close the lock chassis aperture  14  apart from a driver-receiving bore  54  therethrough. The front plate  52  configuration complements that of the aperture  14 , and therefore, the illustrated front plate  52  has a figure-8 configuration like that of the illustrative chassis aperture  14 . A tubular portion  56  extends rearwardly from the front plate  52  and is co-axial with the bore  54 . The tubular portion  56  and the bore  54  define a passage  55  that aligns with the pins  22  of the lock chassis drive system  20  when the core  50  is inserted into the chamber  18 . The tubular portion  56  is sized and configured such that it can be received into the chamber  18  without its outer extents E interfering with the control lug projections  26 , but with an opening  58  adjacent to one of the projections  26 . In the preferred embodiment, the tubular portion  56  is circular to complement the lower half of the figure-8 shaped aperture  14  and chamber  18 , however, other shapes are possible.  
         [0020]    A flange  60  extends inwardly through the tubular open portion  58 . The flange  60  includes an arm  62  having a driver engaging point  64  depending from its inward surface and a projection engaging block  66  extending from its outward surface. The arm  62  from the tubular portion  56  and is biased toward a position in which the driver engaging point  64  is within the passage  55  and the protrusion engaging block  66  is proximate the outward extents E of the tubular portion  56 .  
         [0021]    As can be seen in FIGS. 5 and 6, the engaging point  64  is defined by opposed angled surfaces  65   a ,  65   b . The block  66  includes a generally triangular portion  68 , defined by a rear surface  70 , a top surface  72  and a diagonal surface  74  extending therebetween, and an arched reinforcement portion  76 . The top surface  72  is substantially parallel to the outward surface of the arm  62  such that when the arm  62  is at its rest position, biased inward, the top surface  72  also slopes inward. The juncture between the rear surface  70  and the top surface  72  has a chamfered edge  78  and the juncture between the top surface and the diagonal surface  74  define an abutting surface  80 . Referring to FIG. 12, it can be seen that the flange  60  is configured such that the abutting surface  80  is adjacent the rear contacting surface  27  of the projection  26  upon full insertion of the core  50  into the chamber  18 .  
         [0022]    Referring to FIGS. 2 and 7- 9 , the preferred driver  100  includes a handle  102  and a shaft  104  configured to be received within the passage  55 . The shaft  104  extends from the handle  102  and terminates in a leading surface  106 . A plurality of bores  108  extend through the leading surface  106  and the length of the shaft  104 . The number and configuration of the bores  108  complements the number, size and positioning of the lock pins  22  such that the pins  22  are received into the bores  108  when the shaft  104  is inserted in a given orientation. The shaft  104  is preferably substantially hollow from the handle  102  to the leading surface  106  such that a user can see through the driver  100  to align the pins  22  if necessary. As shown in FIG. 7, the bores  108  preferably extend into the circumferential wall  107  of the shaft  104  such that the pins  22  are acted on by the shaft walls  107  in addition to the leading surface  106 .  
         [0023]    The shaft  104  includes a taper  109  adjacent the leading surface  106  and a plurality of spaced apart, outer peripheral grooves  110   a,b,c . Each groove  110   a,b,c  is defined by intersecting tapered walls  112 ,  114 . The grooves  110   a,b,c  are configured to receive and engage the flange drive engaging point  64 . The plurality of grooves  110  allows the drive  100  to be used with lock chassises  10  having different chamber depths due to, for example, the number of pins of the intended keyed core.  
         [0024]    Having described the components of the preferred embodiment of the present invention, its operation will now be described with reference to FIGS.  10 - 18 .  
         [0025]    Referring to FIGS.  10 - 12 , the core  50  is inserted through the aperture  14  and into the chamber  18  until the front plate  52  is received in the aperture  14  and contacts the aperture rim  15 . As the core  50  is inserted, the chamfered edge  78  of the block  64  may contact the lug projection  26 . The resiliency of the flange  60  allows it to flex inward as the projection  26  rides along the chamfered edge  68  and return to its original position once the chamfered edge  78  passes the projection  26 . Upon complete insertion, the flange abutting surface  80  is aligned with the contact surface  27  of the projection  26 , however, since the flange  60  is biased-inward, the abutting surface  80  is not in contact with the projection  26 .  
         [0026]    Referring to FIGS.  13 - 15 , the driver  100  is inserted into the passage  55  defined by the bore  54  and tube  56 . As the drive shaft  104  is inserted, the forward tapered surface  65   a  of the flange engaging point  64  rides up the taper  109  at the leading surface of the shaft  104  as the flange  60  flexes outward. The abutting surface  80  of the outwardly flexed flange  60  engages the contact surface  27  of the projection  26 , thereby preventing removal of the core  50 .  
         [0027]    Referring to FIGS.  16 - 18 , the driver shaft  104  is inserted the appropriate depth for the given core-receiving chamber  18  (in the illustrated embodiment, the driver is inserted completely). As the driver shaft  104  is inserted, the pins  22  are received in the bores  108 . Since the tube  56  encircles the shaft  104 , it prevents tilting of the shaft  104  out of alignment, and instead maintains axial alignment to allow easy engagement of the pins  22 . As explained above, the hollow driver  100  allows a user to easily visually rotationally align the bores  108  with the pins  22  if needed. Also, as the shaft  104  is inserted, the driver engaging point  64  engages the appropriate peripheral groove  110 . The tapered surfaces  112 ,  114 ,  65   a ,  65   b  of the grooves  110  and the point  64  allow the point  64  to engage and relatively easily disengage the forward grooves  110   a,b , for example, as the shaft  104  is completely inserted. Once the shaft  104  is inserted to the desired depth, the point  64  engages the respective groove  110   c  with sufficient rigidity to prevent inadvertent dislodging of the driver  100 , but easily gives way upon a more substantial force to withdraw the shaft  104 . With the shaft  104  inserted, a user can operate the lock chassis drive system  20  by simply turning the handle  102  which in turn causes rotation of the pins  22 .  
         [0028]    When it is time to remove the lock actuator  40 , the driver  100  is removed by simply applying an outward.force. Again, the tapered surfaces  65   a ,  65   b ,  112 ,  114  allow the flange point  64  to ride out of the grooves  110  and give way to the withdrawal force. Upon removal of the shaft  104 , the flange  60  resiliently returns to its inward position and the abutting surface  80  disengages the contact surface  27 . In this position, the top surface  72  of the block  66  is sloped inward, see FIG. 12, such that as the core  50  is pulled out of the chamber  18 , the flange  60  is moved inward to clear the projection  26  as it rides along the top surface  72 . The lock actuator  40  can then be saved for future use or disposed of as desired. Due to its inexpensive manufacture and its lack of potential security breach, a thorough accounting of the actuators  40  is not necessary.

Technology Classification (CPC): 8