GB2487211A

GB2487211A - Circular latch plate

Info

Publication number: GB2487211A
Application number: GB1100514.7A
Authority: GB
Inventors: Tony Wayne Hedges
Original assignee: Individual
Current assignee: Individual
Priority date: 2011-01-13
Filing date: 2011-01-13
Publication date: 2012-07-18
Also published as: GB201100514D0

Abstract

Disclosed is a circular plate 4 for a lock 1 with a latch 3. Plate 4 is adapted to be positioned in a recess 12 in a door edge 10A. Plate 4 has a latch aperture 5 through which a latch 3can reciprocate, and means 6, 7 ,8A, 8B to secure the circular plate in a recess. The invention also relates to a lock or striking plate incorporating the circular plate.

Description

Title: Circular Plate for Loc with latch The present invention relates to a circular plate for a lock with a latch.

It is well known to place a lock in the form of a tube latch into the edge of a door which is operated by a square shaft in a rotable square collar in the tube latch rotated between two door handles. The tube latch has a rectangular end plate with a latch aperture in it through which a latch reciprocates, and from which extends a tubular housing supporting a spring biased latch.

The tube is supported in a tubular aperture extending inwards from the edge of the door, and the rectangular plate, supporting the tube, is held in a rectangular shallow recess in the edge of the door with retaining screws passing through holes the plate. The rectangular plate is thus substantially flush with the edge of the door.

A problem with such known tube latches is that when fitting them, it takes some time for a skilled trades person to cut the rectangular shallow recess. This adds to the cost of fitting tube latches. Other types of locks with latches such as mortice locks also use rectangular plates which make them time consuming to fit also.

It is known to provide striking plates to engage and depress a lock latch. Striking plates are mounted on a door frame over a rectangular aperture in the door frame to receive the latch.

Striking plates are rectangular and need to be fined in a shallow rectangular recess in the door frame. Again it takes some time for a skilled trades person to cut the rectangular shallow recess, and this adds to the cost of fitting tube latches. Also the rectangular aperture needs to be cut out of the door frame which is time consuming.

The invention seeks to provide a solution to this problem.

According to the present invention there is provided a circular plate for a lock with a latch, said plate adapted to be positioned in a recess in a door edge or door frame, said plate having a latch aperture through which a latch can reciprocate, and securement means to secure the circular plate in a recess.

Preferably the securement means is in the form of at least one screw (more preferably at least two screws), the or each screw passing through a cut-out in the plate. The cut-out may be a circular cut-out in the plate or a cut-out in the perimeter of the plate. The cut-out in the perimeter of the plate may be semicircular or part of a circle. The cut-out may include a tapered recess to receive a tapered screw head.

The invention also relates to a lock, said lock having an end plate in the form of a circular plate as defined above. The lock may be a tube latch or a mortice lock.

The also relates to a striking plate comprising a circular plate as above defined having a latch guide extending from the perimeter of the plate.

An embodiment of the invention will now be described with reference to the accompanying drawings in which: Figure 1 shows a view of a tube latch with a circular end plate, and Figure 2 shows a striking plate.

Referring to Figure 1 there is shown a tube latch 1 for insertion into the edge IOA of a door 10 (only part of door 10 and edge 1OA is shown). Door 10 may be of a type well known in the art and need not be described herein. Edge 1OA has a tubular aperture 11 and a circular recess 12 with diametrically opposed screw holes 13A,13B.

Tube latch I has a tubular housing 2 with a rectangular latch 3 with a curved latch face 3A. A circular end plate 4 is provided at one end of housing 2 having a rectangular aperture 5 through which latch 3 can reciprocate. Housing 2 has a rotatable square collar 9 to operate the latch as is known in the art.

A pair of diametrically opposed semicircular (or part of a circle) cut-outs 6,7 are provided in the perimeter of plate 4 to engage with tapered heads of screws 8A,8B to secure the plate 4 into the door circular recess 12, whereby plate 4 is substantially "flush" with door edge 1OA. Each cut-out has a tapered recess 6A,7A to receive the heads of screws 8A,8B. Screws 8A,8B and cut-outs 6,7 provide a securement means to secure the circular plate in a recess 12. The tapered recesses 6A,7A ensure the top face of the screw heads of screws 8A,8B are "flush with the exposed face of plate 4.

In order to fit tube latch 1 with plate 4 in the edge lOAof the door, recess 12 is first formed with a wide drill bit (typically of the order of 30mm wide) and drill. Aperture 11 (in co-axial alignment with recess circular 12) is then formed with a narrower drill bit and drill (typically of the order of 23mm wide). The tube latch 1 is then inserted into the door edge 1OA and then the plate 4 is secured in recess 12 using screws 8A,SB. Plate 4 may typically be 2mm thick and recess 12 may typically be 2mm deep.

The circular plate 4 obviates the need for the skilled and time consuming process of forming a rectangular recess in a door edge using chisels when fining tube latches with rectangular plates.

All that is required is two simple drilling operations. The spacing of screw holes l3A, l3B for screws 8A,8B also ensures that screws SA,SB are firmly embedded in the door wood well away from the aperture 11.

Referring now to Figure 2, there is shown a striking plate 20 mountable on a door frame 30 adjacent a door frame door stop 31. Door frame 30 has a tubular aperture 32 and a shallow circular recess 33 with diametrically opposed screw holes 34A,34B. A guide recess 35 extends from the circular recess 33 to the edge of the door frame. Circular recess 33 and guide recess 35 is adapted to receive striking plate 20.

Striking plate 20 is designed to receive and depress the latch 3 of a tube latch 1 shown in Figure 1 and cover circular aperture 32 in the door frame which receives the latch 3.

Striking plate 20 has a circular plate 21 and a curved latch guide 22 extending from the perimeter of the plate 21. Circular plate 21 has a rectangular aperture 23 through which latch 3 can reciprocate.

A pair of diametrically opposed semicircular (or part of a circle) cut-outs 24,25 are provided in the perimeter of plate 21 to engage with tapered heads of screws 26A,26B to secure the plate 21 with guide 22 into the door frame circular recess 33 and recess 35, whereby plate 21 is substantially "flush" with door frame 30. Each cut-out has a tapered recess 24A,25A to receive the heads of screws 26A,2613. Screws 26A,26B and cut-outs 2425 provide a securement means to secure the circular plate 21 in a recess 33. The recess 24A,25A ensure the top face of the screw heads of screws 26A,268 are "flush with the exposed face of plate 21.

In order to fit plate 21 with guide 22 in the door frame 30, recess 33 is first formed with a wide drill bit (typically of the order of 30mm wide) and drill and recess 35 made with a chisel.

Aperture 32 (in co-axial alignment with circular recess 33) is then formed with a narrower drill bit and drill (typically of the order of 23mm wide). The plate 21 with guide 22 is then inserted into the door frame recess 33, and then the plate is secured in recess 33 using screws 26A,26B.

Plate 21 may typically be 2mmm thick and recess 33 may typically be 2mm deep.

The circular plate 21 obviates the need for the skilled and time consuming process of forming a rectangular recess in the door frame using chisels when fitting rectangular striking plates. All that is required is two simple drilling operations. The spacing of screw holes 34A,34B for screws 26A,26B also ensures that screws 26A,26B are firmly embedded in the door frame wood well away from the aperture 32.

The invention may take a form different to that specifically described above. For example the cut-outs could circular cut-outs in the circular plate rather than the perimeter of the plate. The use of a circular plate which can be recessed in a door or door frame can be used with locks with latches other than tube latches. For example lock may be a mortice lock, e.g. of the type with a latch bolt which extends top or bottom of a door or window into a door frame.

Further modifications will be apparent to those skilled in the art without departing from the scope of the present invention

Claims

CLAIMS1. A circular plate for a lock with a latch, said plate adapted to be positioned in a recess in a door edge or door frame, said plate having a latch aperture through which a latch can reciprocate, and securement means to secure the circular plate in a recess.
2. A circular plate according to claim 1, wherein the securement means is in the form of at least one screw, and the or each screw passing through a cut-out in the plate.
3. A circular plate according to claim 1 or 2, wherein the or each cut-out is a circular cut-out in the plate.
4. A circular plate according to claim 1 or 2, wherein the or each cut-out is in the perimeter of the plate.
5. A circular plate according to claim 4, wherein the or each cut-out in the perimeter of the plate is semicircular or part of a circle.
6. A circular plate according to any of claims 2 to 5, wherein the cut-out includes a tapered recess to receive a tapered screw head.
7. A lock, said lock having an end plate in the form of a circular plate according to any preceding claim.
8. A lock according to claim 7 in the form of a tube latch.
9. A lock according to claim 7 in the form of a mortice lock.
10. A striking plate comprising a circular plate according to any preceding claim and a latch guide extending from the perimeter of the plate.
11. A circular plate substantially as hereinbefore described with reference to and as shown in the accompanying drawings.
12. A lock substantially as hereinbefore described with reference to and as shown in the accompanying drawings.
13. A striking plate substantially as hereinbefore described with reference to and as shown in the accompanying drawings.