Abstract:
The present invention provides a cost effective security locking mechanism for improving the security between a frame member and the masonry surrounding the frame member and additionally for enhancing the strength of engagement between the frame and a door associated with the frame. A substantial proportion of any force exerted on the door, when in the locked condition, is transmitted directly to the masonry surrounding the frame by means of auxiliary bolts and tubular metal anchorages.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to a security locking mechanism for enhancing the security provided by a lock carried by a wing such as a door or window. 
     2. Description of the Related Art 
     It has always been advantageous to provide a door, window or the like with a number of locking devices so as to deter or prevent a would-be intruder. Conventionally, this has been achieved by installing on the wing, or indeed on a frame associated with the wing, a plurality of separate locking devices each requiring a separate key or handle. Naturally, the operation of such a system is a relatively arduous and time consuming task. 
     DE 19723361 discloses a novel and simple locking system that has, to some extent, alleviated the problems associated with the aforementioned system. This document describes a system wherein the insertion of a single bolt from a door into a keeper in the associated frame simultaneously causes the extension of auxiliary bolts from the frame member into housings provided on the door. This system enhances the security between, and the engagement of, the door and the frame. 
     Although door security is improving continuously, the majority of the development carried out in this field is primarily concerned with improving the strength of the door or, as discussed in DE 19723361, improving the strength of engagement between the door and its frame. 
     Insofar as the applicant is aware, there has not been a comparable improvement in the security provided between the door frame and the surrounding masonry to which it is affixed. A member of the public may choose to install a system such as that disclosed in DE 19723361 into a door and its associated frame. This undoubtedly would improve the strength of engagement between the two members and any force exerted on the door would be transmitted directly to the frame. However, repetitive forcing or barrage of the door induces stress within the frame and eventually the frame, which is normally quite a weak member, would yield. 
     Accordingly, the present invention seeks to redress the problems discussed above by providing an easy to use and cost effective locking mechanism which improves the security between the frame and the surrounding masonry as well enhancing the strength of engagement of the door and the frame. The mechanism reduces the stress induced in the frame by transmitting a substantial proportion of the force exerted on the door directly to the masonry surrounding the frame. Furthermore, this new locking device can be retrofitted to existing doors without the need for providing a new lock. 
     BRIEF SUMMARY OF THE INVENTION 
     A security locking mechanism for enhancing the security provided by a lock carried by a wing such as a door or window, the security locking mechanism comprising an auxiliary bolt mechanism for mounting in a frame for the wing and an auxiliary keeper for mounting in the wing, wherein extension of a bolt of the lock into a keeper of the auxiliary bolt mechanism causes extension of an auxiliary bolt of the auxiliary bolt mechanism into the auxiliary keeper against a resilient bias, the auxiliary bolt mechanism comprising a metal housing which in use is received in a recess in the frame and an actuating lever which is pivotally mounted intermediate its ends in the housing, is pivotally connected at one end portion to a keeper plate positioned to be depressed by extension of the bolt into the keeper, and is pivotally connected at the opposite end portion to the auxiliary bolt, wherein the auxiliary bolt is slidable in a tubular metal anchorage which projects rearwardly from the metal housing and in use is received in and anchored by the masonry or other structural support for the frame; and when extended against the resilient bias the auxiliary bolt has one end portion received in the tubular metal anchorage and the other end portion received in the auxiliary keeper of the wing. 
     Preferably, the keeper plate is fast to a shaft which is axially slidable in a tubular metal guide which projects rearwardly from the metal housing and in use is received in and anchored by the masonry or other structural support for the frame. 
     The security locking mechanism may be used in association with a surface-mounted lock, wherein the keeper in use is located outside the width of the frame alongside the surface-mounted lock, and the keeper plate bridges the width of the frame and the keeper so that extension of the bolt of the lock into the keeper outside the width of the frame is communicated by the keeper plate to the lever and auxiliary bolt within the width of the frame. Such a surface-mounted lock is one which has as its sole bolt a latch bolt. 
     Alternatively, the security locking mechanism may be used in association with a lock which has both a latch bolt and a deadbolt, wherein the keeper plate is positioned in the housing so as to be depressed by extension of either the latch bolt or the deadbolt into the keeper. 
     Preferably, the auxiliary bolt mechanism comprises a second actuating lever on the opposite side of the keeper plate to the actuating lever, the second actuating lever being pivotally mounted intermediate its ends in the housing, being pivotally connected at one end portion to the keeper plate and being pivotally connected at its opposite end portion to a second auxiliary bolt which is slidable in a second tubular metal anchorage which projects rearwardly from the metal housing and in use is received in and anchored by the masonry or other structural support for the frame. 
     The security locking mechanism may further comprise a metal face plate securable to the front of the metal housing. Additionally, a pair of tubular metal structural members can be secured to the back wall of the metal housing and extending from the back wall to the metal face plate, and in alignment with the tubular metal structural members fixing holes formed through the face plate and the back wall of the metal housing, for fixing the face plate and housing directly to the masonry or other structural support for the frame by means of securing screws or bolts passing through the fixing holes, the tubular metal structural members and the frame and obtaining an anchorage in the masonry or other structural support. 
     The housing may be provided with a deformable member or housing portion in the region of the keeper plate, positioned so that if an attempt is made to force open the wing while it is locked, the deformable member will bend into a position blocking keeper plate movement, in which position it prevents the keeper plate from returning from its depressed condition even when the bolt is withdrawn. 
     Additionally, the security locking mechanism can be provided with a release mechanism connected to the actuating lever and passing through a side wall of the housing and in use through the frame to one side only of the frame, for moving the actuating lever so as to disengage the auxiliary bolt mechanism in the event that the mechanism sticks in the locking condition. 
     The security locking mechanism may be extended using a supplementary locking mechanism. Such a supplementary locking mechanism can be used for securing the door to the frame, and includes: a supplementary bolt, housed within and extensible from the door, for spanning the gap between the door and the frame, the supplementary bolt being resiliently biased to a retracted condition in which the door is movable relative to the frame; a supplementary actuating lever pivotally mounted at a position intermediate of its ends in the door and having one end portion engagable with the supplementary bolt to move the supplementary bolt against the resilient bias to a position spanning said gap, the other end portion of the supplementary actuating lever being engagable with the auxiliary bolt of the security locking mechanism such that extension of the auxiliary bolt into the auxiliary keeper in the wing causes pivotal rotation of the supplementary actuating lever to move the supplementary bolt against the resilient bias for receipt within a keeper formed in the frame. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an exploded perspective view of a first embodiment of a security locking mechanism according to the invention; 
     FIG. 2 is an exploded sectional side view of the locking mechanism of FIG. 1 in an open or unlocked position; 
     FIG. 3 is an exploded sectional side view of the locking mechanism of FIGS. 1 and 2 in a closed or locked position; and 
     FIG. 4 is an exploded perspective view of a second embodiment of a security locking mechanism according to the invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIGS. 1,  2  and  3  show a security locking mechanism according to the invention. The locking mechanism comprises an auxiliary bolt mechanism  2  which is mounted within a recess  8  provided in a door frame  6  and anchored to the masonry or other structural support  4  surrounding the frame  6 . The auxiliary bolt mechanism  2  is activated by extension of a bolt from a lock carried by a door (depicted in dotted lines in FIGS.  2  and  3 ). 
     FIG. 1, in particular, shows an embodiment of the present invention which is for use in conjunction with a sash-type lock provided in a door. 
     The auxiliary bolt mechanism  2  has a metal monocoque housing  10  having a single exposed open surface. The housing  10  is anchored through the door frame  6  and embedded therein within the recess  8 . Anchorage to the surrounding masonry is achieved by means of two hollow tubular metal anchorages  12  and a hollow tubular metal guide  14 . The tubular metal anchorages  12  are located substantially at either end of the auxiliary bolt mechanism  2  on the rearwardly facing side of the monocoque housing  10  (that side which opposes the open surface of the monocoque housing  10 ) and extend therefrom into the surrounding masonry  4  through the recess  8  formed in the frame  6 . The tubular metal guide  14  is positioned substantially in the middle of the auxiliary bolt mechanism  2  on the rearwardly facing side of the monocoque housing  10  and extends therefrom, in a similar manner, into the masonry  4 . 
     The moving parts of the auxiliary bolt mechanism  2  are contained within the monocoque housing  10  and these will be described later on in the description. 
     The exposed open surface of the monocoque housing  10  is covered with a metal face plate  20  which is fitted flush with the exposed surface of the door frame  6 . Fixing screws  22  are used to fasten the face plate  20  to the housing  10  and to secure the face plate  20  to the frame  6 . Two long tapered masonry screws  24  are used to secure the auxiliary bolt mechanism  2  to the masonry  4  surrounding the frame  6 . These masonry screws  24  are inserted through holes in the face plate  20  and pass through hollow cylindrical metal shafts  26  extending from the face plate  20  to the rear of the housing  10 . The masonry screws  24  then extend through holes provided in the rearwardly facing surface of the monocoque housing  10 , through the base of the recess  8  provided within the frame  6  and into the masonry  4  surrounding the frame  6 . 
     The metal face plate  20  is further provided with a keeper  30  into which a latch bolt and/or a deadbolt extensible from the door may be inserted to abut a keeper plate  32  provided within the monocoque housing  10  thereby activating the auxiliary bolt mechanism  2 . The keeper plate  32  is provided with a guidance shaft  34  which is slidably received within the hollow tubular guide  14  mounted on the rearward face of the housing  10 . The guidance shaft  34  is of such a length that when the keeper plate  32  is in its non-depressed condition (in abutment with the face plate  20 ), a portion of the guidance shaft  34  is still received in the hollow tubular guide  14 . This ensures smooth, non-fouling movement of the keeper plate  32  when a bolt is inserted into the monocoque housing  10  through the keeper  30  on the face plate  20 . 
     The inner face of the keeper plate  32  engages with two actuating levers  40 . The first of these actuating levers  40  extends upwards from the keeper plate  32 , while the second of the actuating levers  40  extends downwards from the keeper plate  32 . 
     A pivot pin  42  is inserted through a pivot hole  46  provided on each of the actuating levers  40  at an intermediate position thereof. Each such pivot pin  42  is secured to the metal monocoque housing  10  at a pivot point  44 . A plurality of pivot points  44  and corresponding pivot holes  46  are provided on the monocoque housing  10  and actuating lever  40  respectively. This enables the user to select one out of a range of moments that the actuating lever  40  may have about the pivot pin  42  depending upon the circumstances of installation. 
     The other end of each actuating lever  40  is double pronged and an auxiliary bolt  50  is positioned in the gap provided between the prongs  48 . The auxiliary bolt  50  is provided with a holding pin which engages with a holding recess in one or each of the prongs  48  of the actuating lever  40 . The holding recess may be in the form of a simple hole through which the holding pin is inserted. Alternatively, the holding recess may be arcuate in which case the holding pin can be snap-fitted into the holding recess. 
     The auxiliary bolt  50  is slidably housed within the tubular metal anchorage  12  and is of such a length that on full extension (the locked condition), a portion of the auxiliary bolt  50  remains within the tubular metal anchorage  12 . Thereby, when the auxiliary bolt mechanism  2  assumes the locked position, a substantial portion of the force exerted on the door will be transferred to the surrounding masonry  4  through auxiliary keepers  52  formed within the door  5 , the auxiliary bolts  50 , the metal monocoque housing  10 , the masonry screws  24 , the tubular metal guide  14  and the tubular metal anchorages  12 . 
     A leaf spring  60  is mounted on each of the actuating levers  40  at an intermediate section thereof at the side of the pivot pin  42  which is remote from the keeper plate  32 . Each leaf spring  60  is disposed between the actuating lever  40  and the metal face plate  20  for engagement with the face plate  20  on rotation of the associated actuating lever  40 . 
     As illustrated in FIG. 3, in operation, on extension of the latch bolt or deadbolt through the keeper  30  and into the metal monocoque housing  10 , the keeper plate  32  is pushed to the rear of the housing  10  and the actuating levers  40  rotate resulting in extension of the auxiliary bolts  50  out from the housing  10  against the biasing force developed by the leaf springs  60  through auxiliary bolt holes provided on the face plate  20  for engagement with auxiliary keepers  52  housed within the door  5 . 
     Conversely, as shown in FIG. 2, as the latch bolt or deadbolt is removed from the keeper  30 , the leaf springs  60  are of sufficient strength to withdraw the auxiliary bolts  50  from the auxiliary keepers  52  and into the housing  10  and are simultaneously capable of traversing the keeper plate  32  to the front of the monocoque housing  10 . 
     There may be occasions when the auxiliary bolts  50  fail to retract back into the monocoque housing  10  when the bolt from the door is withdrawn from the keeper  30 . For this reason there is provided an emergency release cam mechanism  70  within the monocoque housing  10  which engages with one of the actuating levers  40  of the auxiliary bolt mechanism  2 . The cam mechanism  70  is accessible from one side of the frame through an access hole  72  provided therein. If necessary, a screw driver can be inserted into the access hole  72  for rotatable engagement with the cam mechanism  70  which in turn rotates the actuating lever  40  which it engages thereby traversing the keeper plate  32  to the front of the monocoque housing  10  and retracting both auxiliary bolts  50  back into the housing  10 . 
     FIG. 4 shows a further embodiment of the security locking mechanism. It differs from the embodiment previously described in that it is used in conjunction with a door provided with a surface mounted night latch. In this instance, the keeper  30  on the metal face plate  20  is located outside the width of the frame  6  and the keeper plate  32  bridges the width of the frame  6  and the keeper  30  so that extension of the bolt of the lock into the keeper  30  is communicated by the keeper plate  32  to the actuating levers  40  and auxiliary bolts  50  housed within the metal monocoque housing  10 . This embodiment functions in a similar manner to that previously described. 
     While the invention has been described with reference to details of the illustrated embodiment, these details are not intended to limit the scope of the invention as defined in the appended claims.