Patent Publication Number: US-2007101777-A1

Title: Escutcheon assembly

Description:
BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates to an escutcheon assembly. More specifically, the present invention relates to an escutcheon assembly for a lock having an interchangeable lock core of figure-8 cross section.  
      2. Description of the Related Art  
      U.S. Pat. No. 4,873,853 discloses an escutcheon assembly for receiving a lock cylinder having an interchangeable lock core of figure-8 cross section. The escutcheon assembly comprises a cover plate and a pair of mounting posts for attaching the cover plate to a door. The cover plate includes a lock cylinder-receiving cavity for holding a lock cylinder. The lock cylinder-receiving cavity includes an annular rear opening and a figure-8-shaped front aperture. An interchangeable lock core is received in a lock body of the lock cylinder. In use, the interchangeable lock core is easily removable from its home in the lock body of the lock cylinder through the figure-8-shaped aperture by using a conventional control key to release the lock core in the normal way. The lock core has a figure-8-shaped cross section matching the shape of the front aperture so that the lock core can be easily pulled out from the lock body without removal or disruption of the mounted cover plate. Thus, the escutcheon assembly presents a sleek, attractive appearance without obstructing removal of the interchangeable lock core from the lock cylinder, for one can only see the figure-8-shaped front face of the lock core via the figure-8-shaped front opening from outside.  
      However, the cover plate must be thick enough to provide sufficient strength and the lock cylinder-receiving cavity must be wide enough to receive the lock cylinder such that the cover plate must be manufactured by forging or casting. The manufacturing cost is high and manufacturing flexibility is limited. Further, the cover plate is fixed to the door by a pair of screws passing through the mounting posts, which screws are exposed on an inner side of the door, adversely affecting the appearance. Further, when the outer face of the cover plate stains or rusts, the replacement of the cover plate is troublesome and costly.  
     SUMMARY OF THE INVENTION  
      An escutcheon assembly in accordance with the present invention is provided for a lock comprising a lock cylinder that includes a lock body and an interchangeable lock core that is removably mounted in the lock body and that has a figure-8-shaped cross section.  
      The escutcheon assembly in accordance with the present invention comprises a mounting plate and a cover plate. The mounting plate is adapted to be mounted to a front face of a door. The mounting plate comprises a receiving section for receiving the lock body. The cover plate is securely mounted around the mounting plate. The cover plate comprises a figure-8-shaped through-hole aligned with the figure-8-shaped cross section of the interchangeable lock core.  
      The mounting plate and the cover plate can be made by inexpensive punching. Replacement of the cover plate, when desired, can be easily achieved at a low cost.  
      Preferably, the receiving section of the cover plate comprises a recessed portion extending rearward from an inner face of the mounting plate. The receiving section comprises an end wall having a through-hole through which the lock body extends.  
      Preferably, the cover plate comprises a perimeter wall securely engaged with a perimeter of the mounting plate.  
      Preferably, the figure-8-shaped through-hole of the cover plate has a size substantially the same as that of the figure-8-shaped cross section of the interchangeable lock core.  
      Preferably, the mounting plate comprises two mounting posts each having a screw hole, and two screws extend into the screw holes of the mounting posts for fixing the mounting plate to the door.  
      Preferably, the cover plate further comprises an opening through which an end of an outside handle extends.  
      Other objectives, advantages, and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a front elevational view of an escutcheon assembly in accordance with the present invention mounted on a door.  
       FIG. 2  is a sectional view taken along plane  2 - 2  in  FIG. 1 .  
       FIG. 3  is an exploded perspective view of the escutcheon assembly in accordance with the present invention.  
       FIG. 4  is an enlarged view of a portion of the escutcheon assembly in  FIG. 2 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
      Referring to  FIGS. 1 through 4 , an escutcheon assembly  4  in accordance with the present invention comprises a mounting plate  41  and a cover plate  42 . The mounting plate  41  is mounted to an outer face of a door  2  and the cover plate  42  is mounted around the mounting plate  41  and covers the mounting plate  41 .  
      Referring to  FIG. 3 , the door  2  includes a compartment  22  in an edge thereof for receiving a lock case  1 . In this example, the lock case  1  includes a latch bolt  11  operable by turning an inside handle  13  or an outside handle  14 . The lock case  1  further includes a deadbolt  12  operable by turning a lock core  31  of a lock cylinder  3 .  
      The lock core  31  is an interchangeable lock core having a figure-8-shaped cross section. The lock core  31  comprises an upper lobe  311  and a lower lobe  312 . A key plug  313  is mounted in the lower lobe  312  and includes a keyway  314 . The lock core  31  is mounted in a hollow lock body  32  of the lock cylinder  3 . The lock body  32  includes a threaded rear end  321  for threadedly engaging with a screw hole  15  in the lock case  1  after passing through a hole  23  in the door  2 .  
      The mounting plate  41  comprises two mounting posts  411  respectively extending through mounting holes  24  in the door  2 , with two screws  16  respectively extending through a fixing plate  17  mounted to an inner face of the door  2  into screw holes (not labeled) in the respective mounting posts  411 , thereby fixing the mounting plate  41  and the fixing plate  17  in place, as shown in  FIG. 3 .  
      Referring to  FIG. 4 , the mounting plate  41  comprises a receiving section  412  for receiving the lock body  32 . In this example, the receiving section  412  is a substantially hollow section extending rearward from an inner face of the mounting plate  41  to form a recessed portion  414 . The receiving section  412  includes an end wall  415  with a through-hole  413  through which the lock body  32  extends. Preferably, a flange  322  on a front end of the lock body  32  is received in the recessed portion  414  such that the front face of the lock body  32  is flush with the front face of the mounting plate  41 . The rear threaded end  321  of the lock body  32  is threadedly engaged with the screw hole  15  of the lock case  1 .  
      The cover plate  42  has a perimeter similar to that of the mounting plate  41  and is tightly mounted around the mounting plate  41  by a perimeter wall  420 . The cover plate  42  comprises a figure-8-shaped through-hole  421  aligned with the receiving section  412 . Preferably, the size of the figure-8-shaped through-hole  421  of the cover plate  42  is substantially the same as that of a figure-8-shaped hole  323  of the lock body  32  that receives the lock core  31 . Namely, the size of the figure-8-shaped through-hole  421  of the cover plate  42  is substantially the same as that of the figure-8-shaped cross section of the lock core  31 . When the lock cylinder  3  is mounted in the receiving section  412  and the cover plate  42  is mounted outside the mounting plate  41 , the figure-8-shaped through-hole  421  of the cover plate  42  is aligned with the figure-8-shaped cross section of the lock core  31 , as shown in  FIGS. 1 and 3 .  
      The cover plate  42  may further include an opening  420  through which an end  141  of the outside handle  14  extends. The end  141  of the outside handle  14  is coupled with a shaft  51  of a spring device  5  having a spindle  52  engaged in a spindle hole  19  of the lock case  1 . The mounting plate  41  may include an opening  416  through which the end  141  of the outside handle  14  extends. The spring device  5  is mounted in the opening  416  of the cover plate  42 . Thus, when the outside handle  14  is turned, the spindle  52  is turned to retract the latch bolt  11 , which is conventional.  
      The escutcheon assembly in accordance with the present invention presents a sleek, attractive appearance without obstructing removal of the interchangeable lock core  31  from the lock cylinder  3 , for one can only see the figure-8-shaped front face of the lock core  31  via the figure-8-shaped through-hole  421  of the cover plate  42  from outside. The thicknesses of the mounting plate  41  and the cover plate  42  may be small without affecting the strength. Thus, the mounting plate  41  and the cover plate  42  can be formed by inexpensive punching. The manufacturing cost is cut accordingly. Further, in a case that the cover plate  42  stains or rusts, the replacement of the cover plate  42  is easy and cheap, for it is not necessary to replace the mounting plate  41  and for the cover plate  42  is inexpensive. Further, the screws  16  for fixing the mounting plate  41  is shielded by a plate  18  mounted to an inner face  25  of the door  2 , improving the inner appearance.  
      Although specific embodiments have been illustrated and described, numerous modifications and variations are still possible without departing from the essence of the invention. The scope of the invention is limited by the accompanying claims.