AU656946B2 - Door jamb strenthening plate - Google Patents

Description

C 1 II Our Ref: 423472 656946 P/00/011 Regulation 3:2

AUSTRALIA

Patents Act 1990

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT r

I

Sr ''i t **4 *t ~t 54;5 Applicant(s): Address for Service: Invention Title: M Fletcher 71 Cumberland Road INGELBURN NSW 2565

AUSTRALIA

DAVIES COLLISON CAVE Patent Trade Mark Attorneys Level 10, 10 Barrack Street SYDNEY NSW 2000 Door jamb strenthening plate The following statement is a full description of this invention, incluuing the best method of performing it known to me:- 5020 I 1~- The present invention relates to a door lock security device, and in particular to a door jamb strengthening plate.

With most existing entrance door locking constructions, the deadlock fits through a hole in the striker plate and into a hole in the wooden door jamb. This results in a weakness in design. Thus if the door is forced the deadlock bolt splinters the wood and tears out of the side of the door jamb.

The present invention is provided to ameliorate this problem by providing a door jamb strengthening plate comprising: a side wall; a front wall projecting substantially at right angles to said side wall; at least one opening in the side wall; and means to attach the side wall to a rear surface of a door jamb, whereby, in use, 15 said side wall and front wall are in intimate contact with respective walls of the door jamb, with the opening in said side wall overlaying an opening in said door jamb such that a locking bolt of a door lock extends via the opening in said door jamb into said opening in said side wall.

The present invention will now be described by way of example with reference to the accompanying drawings in which: Fig. 1 illustrates a side view of a door jamb strengthening plate according to one embodiment of the present invention; 5 'Fig. 2 illustrates a front view of the door jamb strengthening plate illustrated in Fig. 1; Fig. 3 is a plan view of the door jamb strengthening plate illustrated in Fig. 1; Fig. 4 is an exploded view of the door jamb strengthening plate, with a cutout to show the guide 11 shown in Fig. 1, and it's attachment to a door jamb; Fig. 5 illustrates the door jamb strengthening plate positioned on a door jamb.

One embodiment of the present invention is shown in the accompanying drawings cb L in which the door jamb strengthening p:\wpdocs\anid\423472\ajc C ,d 0307p:mmb -2 plate 1 comprises a side wall 2, with a front wall 3 normal thereto.

The side wall 2 has two openings 4 and 5 located thereon such that the door jamb strengthening plate 1 can be used for right or left door fittings.

Preferably the plate comprises a side wall of zinc coated flat metal 225mm by 95mm with a thickness of approximately 1.2mm, with the front wall formed by a turned up edge of 15mm width.

A location hole 6 is located in the front wall 3 for initial location of the plate i, such that the opening 4 lines up with the strike plate hole 7 through the door jamb 8.

r Screws 9 are fitted from the strike plate (not shown) side of the door jamb 8 as shown in Figure 4 to secure the strenghtening plate 1 in position as shown in Figure Preferably the screws 9 can extend into the wooden 1 upright frame (not shown) supporting the door jamb 8.

The door jamb strengthening plate 1 can be rebated into the door jamb 8, if required, or if the door jamb is of sufficient thickness the side wall of stengthening plate 1 can be slotted into the door jamb.

Thus in use the lock bolt 10 extends through the striker plate not shown and the striker plate hole 7 in the 8 door jamb 8 and through the opening 4 in the strengthening plate i. Therefore if the door is attempted to be forced Sthe wood of the door jamb 8 in the vicinity of the strike plate hole 7, is reinforced.

Thereby the door jamb strengthening plate 1 is securely attached to the door jamb 8 and as such the lock bolt abuts against the edge of the opening 4, to greatly reduce the chance of the lock bolt 10 tearing though the door jamb 8.

Also in another embodiment the openings 4 and 5 could have the cutout material bent normal to the side wall 2 and front wall 3 to provide a guide 11 ae shown in Figure 3 for the lock bolt 10 and additional strengthening.

It should be obvious to people skilled in the art that I0307p:m b 3 modifications and alterations to the above described door jamb strengthening plate could be made without departing i from the spirit or scope of the present invention.

i i t

I.

I

Claims (4)

1. A door jamb strengthening plate comprising: a side wall; a front wall projecting substantially at right angles to said side wall; at least one opening in the side wall; and i. means to attach the side wall to a rear surface of a door jamb, whereby, in use, |said side wall and front wall are in intimate contact with respective walls of the door i jamb, with the opening in said side wall overlaying an opening in said door jamb such that a locking bolt of a door lock extends via the opening in said door jamb into said J opening in said side wall.

2. A door jamb strengthening plate according to claim 1 wherein the opening in the side wall has a guide means extending in the direction of and substantially parallel to the I 15 front wall.

3. A door jamb strengthening plate according to claim 1 or 2 having two openings in the side wall.

4. A door jamb strengthening plate substantially as hereinbefore described with reference to the accompenying drawings. DATED this 21st day of November, 1994 MAXWELL MAURICE FLETCHER By His Patent Attorneys DAVIES COLLISON CAVE p:\wpdocs\amd\423472\ajc I L ABSTRACT A door jamb strengthening plate having a side wall and a front wall with an opening in the side wall The door jamb strengthening plate is attached to a door jamb with the opening overlaying the lock bolt opening of the door jamb with the front wall reinforcing the door jamb. oI p I I op i *0 0