AU2003262285B2 - An improved lock including anti jemmying features - Google Patents

Description

11917AU

ORIGINAL

Complete Specification Applicant: Title: Address for Service: Inovec Pty Ltd An improved lock including anti jemmying features LESICAR PERRIN, 49 Wright Street, Adelaide, South Australia 5000, Australia The following statement is a full description of this invention, including the best method of performing it known to melus: An improved lock including anti jemmying features BACKGROUND OF THE INVENTION The present invention relates to an improved lock of the type including features that assist in preventing the door from being jemmied.

Quite often, door locks that are mounted in door stiles are easy to jemmy by the use of appropriate force. Although the lock bolt is firmly locked to the lock casing, the casing itself may be moved to disengage the lock bolt with a doorframe.

It is an object of the present invention to propose a lock that assists in preventing the lock bolt from being jemmied.

SUMMARY OF THE INVENTION Therefore in one form of the invention there is proposed a lock assembly for use in a door stile said stile having a cavity defined in part by a rear wall, said assembly including: a front face and a generally parallel spaced apart rear face; a slidable bolt adapted to move inwardly and outwardly of said front face; said rear face substantially parallel to and spaced apart from said stile rear wall; at least one tab substantially thinner than said lock assembly and extending from said lock assembly rear face towards said stile rear wall.

Preferably said lock assembly includes a lock case and a lock lid.

Preferably said tab extends from said lock case. This is generally at the bottom of said case.

Preferably said tab extends from said lock lid. Typically it is the same thickness as the lock lid.

Preferably there are two tabs. Each tab is located on either side of the longitudinal axis of said slidable bolt. This assists in distributing the load on the lock if the door is being jemmied.

Preferably the assembly further includes a sliding bracket adapted to control at least one remote lock, said bracket positioned in between said lock assembly, said tabs and said stile rear wall.

In a further form of the invention there is proposed a lock assembly for use in a door stile having a cavity defined in part by a rear wall, said assembly including: a front face and a generally parallel spaced apart rear face, said rear face generally parallel to and spaced apart from said stile rear wall; at least one tab extending from said lock assembly rear surface towards said stile rear wall and a bracket positioned between said tab and said rear wall.

In a still further from of the invention there is proposed a lock assembly housed in a door and including: a lock case and a lock lid, said assembly having a front face and a rear face; a slidable bolt adapted to move inwardly and outwardly of said front face; at least one tab extending rearwardly from said rear face wherein rearward movement of said lock assembly causes said tab to engage said door.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate several implementations of the invention and, together with the description, serve to explain the advantages and principles of the invention.

In the drawings, Figure 1 is a perspective view of a lock lid for a lock case, the lid embodying the present invention; Figure 2 is a perspective view of the lock lid of Figure 1 when assembled with the lock case; Figure 3 is a perspective view of the lock assembly including the lock lid and lock case of Figure 2 mounted in a door stile and including door furniture; Figure 4 is a horizontal cross-sectional view of the door stile illustrated in Figure 3; Figure 5 is a horizontal cross-sectional view of the lock lid and case when mounted in a door stile, the lock bolt engaging door furniture; Figure 6 is a side sectional view of the lock assembly in the door stile; Figure 7 is a perspective view of an alternate lock assembly embodying the present invention; Figure 8 is a perspective view of a remote lock embodying the present invention; Figure 9 is a perspective partially exploded view of a lock assembly according to a further embodiment of the present invention; and Figure 10 is a sectional side view of the lock assembly of Figure 9.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The following detailed description of the invention refers to the accompanying drawings. Although the description includes exemplary embodiments, other embodiments are possible, and changes may be made to the embodiments described without departing from the spirit and scope of the invention. Wherever possible, the same reference numbers will be used throughout the drawings and the following description to refer to the same and like parts.

Turning now to the drawings in detail and specifically to Figures 1 to 6 there is shown a first embodiment of the present invention. A lock assembly 10 includes a lock case 12 and a lock lid 14. The lock assembly is adapted to fit within a door stile 16, the dimensions of the lock assembly 10 being smaller than the cavity 18 in the door stile to leave a gap 20 between the rear wall 22 of the assembly 10 and the rear wall 24 of the door stile 16. This gap 20 is typically used to house a bracket or linking arm 26 that is used to operate remote locks that may be additionally found towards the top and bottom of the door.

The lid 14 includes various holes and apertures to accommodate the various pats needed to operate a door lock including an aperture 28 to the lock cylinder various screw holes 32 as well as locating holes 34. Various features and operation of the lock assembly would be well known to those versed in the art and it is not intended to discuss these in detail. As the skilled addressee would know, such a lock assembly would also includes additional parts such as lock bolt 36 having a tapered end 38, a lock cover 40, opposing handles 42a and 42b, and locking arm 44. For the detailed operation of these types of locks the reader is referred to other patents in the name of the applicant.

The lock bolt 36 engages recess 46 in door furniture 48. In standard locks, given that there is a gap 20 between the rear wall 24 of the door stile and the rear wall 22 of the lock assembly, anyone that attempts to jemmy the bolt by the use of an appropriate tool can with sufficient force move the whole lock assembly and thus the bolt rearwardly into gap 20 thereby forcing the bolt 36 out of recess 46 and allowing the door to be unlocked.

The present invention seeks to overcome this problem in a first embodiment by providing tabs 48a and 48b extending from the lock cover 14 that extend beyond the lock case 12 to be adjacent the rear wall 24. Anyone forcing the lock assembly 10 rearwardly will then quite quickly abut the tabs 48a and 48b against the rear wall 24 preventing further rearward movement of the lock assembly 10. The tabs 48a and 48b are located so that the lock bolt 36 is located between the two tabs so that any force on the bolt is distributed somewhat evenly between the two tabs. Of course it is to be understood that there may in fact be more than two tabs and it is not intended to limit the invention to only two.

The thickness of the tabs 48a and 48b is typically equal to the thickness of the lock lid 14 so that a rear gap 20 still exists between the rear wall 22 of the lock case and rear wall 24 of the door stile within which can be located bracket 26.

In case a user may need to have the tabs removed, they may be prefabricated with a weakened joint 50 that enables the tab to be easily snapped off.

The embodiment in Figures 1 to 6 illustrated the use of abutting tabs when they were part of the lock lid. In an alternate embodiment and as illustrated in Figure 7, the tabs 52a and 52b may in fact be integral with the lock case 12 rather than the lock lid 14, all other configurations remaining virtually unchanged.

The use of the rear tabs to prevent jemmying of the door bolt can also be applied to remote locks, which are those locks that are linked to the main lock using the bracket 26. Such a lock 54 is illustrated in Figure 8 where the lock includes a lock case 56, lock lid 58, bolt 60, the lock lid 58 including a tab 62 whose outer edge is adjacent the rear wall of the door stile preventing the lock being pushed into the stile.

In an alternate embodiment of the invention and as illustrated in Figures 9 and 10, the lock assembly 10 may include square tabs 64a and 64b that are designed to co-operate with the bracket 26. Thus they abut against the bracket or linkage 26 rather than against the rear wall of the door stile 24. Any jemmying is prevented by the tabs 64a and 64b abutting against inside wall 68 of the bracket 26 that then abuts against the rear wall 24, in a sandwich type of arrangement. To provide for the smooth movement of the bracket 26 alongside the lock assembly bracket 26 driven through pin 70 engaging drive 72, a small gap exists between the tabs and the bracket.

The reader should now appreciate the advantages of the present invention.

When the lock bolt or tongue is jemmied the tabs help to spread the load evenly across the stile. Further they help prevent the lock bolt from being forced out of the door frame.

Further advantages and improvements may very well be made to the present invention without deviating from its scope. Although the invention has been shown and described in what is conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope and spirit of the invention, which is not to be limited to the details disclosed herein but is to be accorded the full scope of the claims so as to embrace any and all equivalent devices and apparatus.

In any claims that follow and in the summary of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprising" is used in the sense of "including", i.e. the features specified may be associated with further features in various embodiments of the invention.

Claims (13)

1. A lock assembly for use in a door stile said stile having a cavity defined in part by a rear wall, said assembly including: a front face and a generally parallel spaced apart rear face; a slidable bolt adapted to move inwardly and outwardly of said front face; said rear face substantially parallel to and spaced apart from said stile rear wall; at least one tab substantially thinner than said lock assembly and extending from said lock assembly rear face towards said stile rear wall.

2. A lock assembly as in claim 1 including a lock case and a lock lid.

3. A lock assembly as in claim 2 wherein said tab extends from said lock case.

4. A lock assembly as in claim 2 wherein said tab extends from said lock lid.

A lock assembly as in any one of the above claims wherein there are two tabs.

6. A lock assembly as claim 5 wherein each tab is located on either side of the longitudinal axis of said slidable bolt.

7. A lock assembly as in any one of the above claims further including a sliding bracket adapted to control at least one remote lock, said bracket positioned in between said lock assembly, said tabs and said stile rear wall.

8. A lock assembly for use in a door stile having a cavity defined in part by a rear wall, said assembly including: a front face and a generally parallel spaced apart rear face, said rear face generally parallel to and spaced apart from said stile rear wall; at least one tab extending from said lock assembly rear surface towards said stile rear wall and a bracket positioned between said tab and said rear wall.

9. A lock assembly housed in a door and including: a lock case and a lock lid, said assembly having a front face and a rear face; a slidable bolt adapted to move inwardly and outwardly of said front face; at least one tab extending rearwardly from said rear face wherein rearward movement of said lock assembly causes said tab to engage said door.

I 8 A lock assembly substantially as hereinbefore described and with reference to Figure 1 to 6.

11. A lock assembly substantially as hereinbefore described and with reference to Figure 7.

12. A lock assembly substantially as hereinbefore described and with reference to Figure 8.

13. A lock assembly substantially as hereinbefore described and with reference to Figures 9 and