Patent Publication Number: US-2013229023-A1

Title: Door jamb security feature

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority of U.S. Provisional Application No. 61/606,752, filed Mar. 5, 2012, the disclosure of which is incorporated herein by reference in its entirety for all purposes. 
    
    
     FIELD OF THE INVENTION 
     The invention relates to a security feature for a door jamb to prevent forced entry. 
     BACKGROUND OF THE INVENTION 
     Door-jambs are typically made of wood; however, wood is not resistant to forced entries that occur during burglaries or acts of vandalism when a tool is used to bend or destroy the area around a door latch. Current door-jambs use a small, generally flat metal plate around the immediate perimeter of the hole in the door jamb which receives a latch or dead bolt; however, the metal plates, known as strike plates, may bend and fail. Therefore, strike plates are also unlikely to provide sufficient resistance to forced entries. 
     There is therefore a need for improved security features to prevent forced entry through a doorway. 
     SUMMARY OF THE INVENTION 
     According to one embodiment of the present invention, an apparatus which provides added security to an entryway is disclosed. The apparatus is affixed to a vertical lockside portion of a door jamb. The apparatus comprises a cover having a height that is less than or equal to the height of the door jamb. The cover includes a main portion having a first end and a second end, a first wall extending from the first end, and a second wall extending from the second end. The main portion is perpendicular to the first and second walls, and the first and second walls are parallel to each other. The apparatus also includes at least one backup plate recessed from a face of the main portion having a hole that is configured to receive a door latch or dead bolt. In the installed condition, the main portion and the first wall rests against and in contact with the vertical lockside portion of the door jamb and the second wall is inserted into the vertical lockside portion of the door jamb. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In order that the invention may be more fully understood, the following figures are provided by way of illustration, in which: 
         FIG. 1  is an exploded view of a cover according to an embodiment of the present invention and a vertical lock-side portion of a door jamb on which the cover is applied. 
         FIG. 2  is a top view of the cover illustrated in  FIG. 1 . 
         FIG. 3  is a top view of the vertical lock-side portion of the door jamb illustrated in  FIG. 1 . 
         FIG. 4  is a top view of the cover illustrated in  FIG. 1  applied to the vertical lock-side portion of the door jamb illustrated in  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Although the invention is illustrated and described herein with reference to specific embodiments, the invention is not intended to be limited to the details shown. Rather, various modifications may be made in the details within the scope and range of equivalents of the claims and without departing from the invention. 
     The present invention provides improved security to a doorway by reinforcing the lock-side of a door jamb. 
     According to a preferred embodiment of the present invention, a cover  20  and the vertical lock-side portion of a door jamb  10  to which the cover  20  is applied is illustrated in  FIG. 1 . The cover  20  provides adequate protective covering to resist the forced entry through a doorway. 
     Referring to  FIG. 2 , the cover  20 , according to one embodiment of the invention, preferably comprises three sections: Two generally parallel walls ( 22 ,  26 ) and a main portion  24  that is generally perpendicular to the two parallel walls ( 22 ,  26 ). Preferably, one of each of the two parallel walls ( 22 ,  26 ) independently extends from one end of the main portion  24 . The two parallel walls ( 22 ,  26 ) extend in the same direction from main portion  24 . The cover  20  may be made of any suitable material of a suitable thickness D which will resist forced warping by a tool, and is preferably made of 16 gauge stainless steel. Preferably, the thickness D of the cover  20  is preferably uniform. The configuration of the embodiment illustrated in  FIG. 2  results in two 90 degree bends. The cover  20 , instead of having a two parallel walls, may include a single wall which is perpendicular to the main portion; however, incorporating multiple 90 degree bends, improves the ability of the cover to resist bending along its length. 
     In the embodiment of the invention illustrated in  FIG. 4 , the cover  20  is in the installed condition on the vertical portion of a lockside door jamb  10 . Of the two parallel walls, a first wall  22  is located on the side of the cover  20  closest to the doorstop  12 . Referring again to  FIG. 2 , the first wall  22  has a width A. A second wall  26  is in opposing relation to the first wall  22  and has a width C. The first width A of the first wall  22  may be equal to the second width C of the second wall  26 ; however, it is preferred that the first width A is less than the second width C providing the cover  20  with a J-shaped cross-section. The first width A is preferably less than a thickness I of the portion  14  of the lockside door jamb  10  on which the cover  10  is applied, but should not be so short that the intended 90 degree bend between the main portion  24  and first wall  22  does not impart any added strength so that the cover  20  will resist bending along its length. 
     Referring to  FIGS. 3 and 4 , the portion  14  of the lockside door jamb  10  includes a groove  16  in which the first wall  22  of the cover  20  is inserted. The thickness H of the groove  16  is preferably equal to the thickness D of the first wall  22 . The depth G of the groove  16  is preferably equal to the width A of the first wall  22 , so that the main portion  24  of the cover  20  rests against the lockside door jamb  10 , and the cover  20  will not interfere with the closing of the door (not shown) hung in the door jamb. It is also preferred that the groove  16  is located a distance E from the end  19  of the lockside jamb  10 , such that the second wall  26  rests against the end  19  of the lockside jamb  10 . Therefore, the distance E is preferably equal to the width B of the main portion  24  of the cover  20  less the thickness of the second wall  26 . 
     The cover of the present invention may be affixed to the lockside jamb according to any method known to those of skill in the art. The embodiment of the invention illustrated in  FIG. 1  preferably includes a plurality of holes ( 25 ,  27 ) in the main portion  24  and second wall  26  of the cover  20 . The holes are preferably in the form of countersink mounting holes, so that the cover may be attached to the lockside jamb with fasteners such as bugle-head screws to prevent the heads of the screws from protruding from the surface of the wall in which they are inserted. The holes may be placed along the main portion  24  and second wall  26  of the cover  20 , such that the holes will align with corresponding pre-drilled holes ( 15 ,  17 ) in the lockside jamb  10 . 
     The present invention also includes at least one opening through which a door latch or dead bolt may be actuated. The openings are preferably located within a recessed backup plate. Referring to the embodiment of the invention illustrated  FIG. 1 , two recessed backup plates ( 28   a ,  28   b ) are each independently located at a height in the main portion  24  of the cover  20 . The backup plates ( 28   a ,  28   b ) are integral to the main portion  24  and are recessed, so that strike plates (not shown) may be inserted into the recesses and will not protrude beyond the face of the main portion  24 . Strike plates are often provided by manufacturers with a deadbolt and/or door latch set. Therefore, the recessed backup plates in the covers according to the present invention should accommodate various sizes and shaped strike plates should it be necessary to change the latch or dead bolt associated with a door that is hung in the door jamb. The lockside jamb  10  preferably includes corresponding cutouts ( 18   a ,  18   b ) that will align and receive the backup plates ( 28   a ,  28   b ) when the cover  20  is installed. 
     It is preferred that the length of the cover spans the entire height of the lockside door jamb; however, the cover may be shorter if such a dimension is found to be effective at resisting forced entries. For example, it may be acceptable for a cover according to the present invention to have a height approximately equal to or slightly longer that the length spanning the one or more openings in which the backup plates are located. Also, the width of the cover, such as the dimension B of the main portion  24  illustrated in  FIG. 2 , may be greater than or equal to the width of the backup plates in the cover. Preferably, the width of the cover is about equal to the width of the backup plate, more preferably with a tolerance of ±0.01″, and most preferably within a tolerance of ±0.005″. Selecting the dimensions in such a way would be more cost-effective as the dimensions would be minimized and less material is needed to fabricate the cover. 
     As used herein throughout the specification and claims, the phrase “about equal” means within a tolerance of 0.25″. 
     While a preferred embodiment of the invention has been shown and described herein, it will be understood that such embodiment is provided by way of example only. Numerous variations, changes, and substitutions will occur to those skilled in the art without departing from the spirit of the invention. Accordingly, it is intended that the appended claims cover all such variations as fall within the spirit and scope of the invention.