EP1455037A1

EP1455037A1 - Door plate

Info

Publication number: EP1455037A1
Application number: EP04251062A
Authority: EP
Inventors: Ian Southall
Original assignee: Fullex Locks Ltd
Current assignee: Fullex Locks Ltd
Priority date: 2003-03-03
Filing date: 2004-02-26
Publication date: 2004-09-08
Also published as: GB0304792D0; GB0404287D0; GB2399857B; GB2399857A

Abstract

The invention relates to a monolithic backing plate 10 for a handle and lock which is resistant to being vandalised over a period of at least 3 minutes, the massive monolithic nature of the backing plate being formed of metal by casting and only having a few relatively thinner parts which have a wall 5 thickness of about 4mm, and resists bending, and breakage.

Description

The invention relates to closures, and particularly to closures such as doors and windows which are operated by a handle such as a lever handle, or a door knob, which extends through a backing plate, which also houses an entry, such as a key hole, to a lock.
Unauthorised entry into a property protected by such a handle/lock combination is becoming increasingly the norm. It takes even a moderately determined burglar or thief no more than about 30 seconds to remove a conventional handle. To do this, it is only necessary for the burglar or thief to tear the door handle from the door by attacking the backing plate, breaking it and thereby gaining access to the lock (usually a cylinder, or barrel, of a cylinder lock) removing it or vandalising it, and thereby gaining unauthorised entry.
It is accordingly an object of the invention to seek to mitigate this disadvantage.
According to the invention there is provided a backing plate adapted for mounting a handle and with access to a lock, comprising means to resist breakage of the backing plate.
Thus using the invention, it is possible to provide a massive, monolithic backing plate which resists deformation or destruction for up to 3 minutes, so deterring an opportunistic burglar, who will not attempt to effect entry over such a long period, and will seek an easier lock target to attack, so preserving the integrity of the property being protected.
The means may comprise a relatively thick metal backing plate which is adapted to resist breakage using, for example, tools specified in British Standard Institute Product Assessment specification 24-1: 1999 (known as PAS 24-1:1999).
The backing plate may have walls of thickness 3mm - 4.5mm, suitably 4.00mm thick. This is a particularly suitable wall thickness when the plate is formed from a unitary workpiece of metal, which is subsequently hollowed out as by machining to form a unitary, light, but strong, owing to the relatively thick walls, backing plate.
The backing plate may be formed as by being cast in one piece with the required wall thickness.
The backing plate may be hollowed out over substantially its whole length, or over only part of its length, in other words the backing plate may have a solid part.
The means may comprise integral ribs, which extend transversely of the length of the backing plate. The ribs may extend across a hollow part of the plate which in use is in abutment with a closure, and/or across a front (in use) surface of the backing plate.
The material of the backing plate may also incorporate separate strengthening means, for example rods or bars of reinforced steel which extend longitudinally, or transversely of the backing plate. Such separate rods or bars may be incorporated in the backing plate during manufacture, or may be added subsequently to manufacture.
The backing plate may include means to mount it on a closure, in the form of stainless steel screws, for example 5mm or 6mm stainless steel screws.
It will be understood that the invention extends to a combination of a back plate as hereinbefore defined and a handle such as a lever handle.
Backing plates embodying the invention are hereinafter described, by way of example, with reference to the accompanying drawings.
Fig. 1 is a front elevational view of a first embodiment of back plate according to the invention;
Fig. 2 is a rear elevational view of the back plate of Fig. 1;
Fig. 3 is a longitudinal sectional view of the back plate of Figs. 1 and 2;
Fig. 4 is a transverse sectional view of the back plate of Fig. 1 taken on the line A-A of that Fig.;
Fig. 5 is a front perspective view of a second embodiment of back plate according to the invention;
Fig. 6 is a rear perspective view of the back plate of Fig. 5; and
Fig. 7 is a rear elevational view of the back plate of Figs. 5 and 6.
Referring to the drawings in which like parts are identified by numerals, there is shown a backing plate 1, 10, for mounting a handle (not shown in Figs. 1 - 4) and for providing access such as a keyhole 2 to a lock such as a cylinder lock (also not shown in Figs. 1 - 4). The handle is mounted in an aperture 3.
In the first embodiment shown in Figs. 1 - 4, the backing plate 1 is formed in one piece as by casting of metal, e.g. Aluminium, Zinc, Brass, Magnesium. The one piece cast metal workpiece is then formed with the keyhole 2 and aperture 3 by suitable means, and is hollowed out on its rear surface to provide a hollow body part 4 defined by a wall 5 of 4mm or more thickness. The hollow part and wall provide means to strengthen the backing plate 1 against disruption when attacked by a jemmy or other tool which might be used by a burglar to try to break the back plate and thus expose the lock to attack, to gain unauthorised entry to a property on which the back plate 1 is mounted e.g. a door or window, by being screwed thereto by 5mm or 6mm stainless steel screws which pass through bosses 6, there being a raised part 7 which seats in a complementary recess formed in the facing surface of the door or window, it being understood that the wall 5 forms, or is part of, a rear surface of the backing plate 1 which abuts the door or closure in use.
Referring now to the second embodiment shown in Figs. 5 to 7, the backing plate 10 is not hollowed out over substantially its whole length as in the first embodiment, rather it is hollowed out over only part of its length.
Thus the back plate 10, made as a one-piece metal casting of a metal such as Aluminium, Zinc, Brass or Magnesium, is only hollowed out at two locations, the first 11 to provide seating for operating mechanism operable by a handle 12, shown in phantom, which is mounted in the aperture 3, and the second 13 of which surrounds the key hole 2. The wall 5 is again of at least 4mm thickness, as considered laterally of the back plate 10 (as in Figs. 1 to 4), while the back plate 10 itself is 13mm or more, say 15.5mm thick, as considered in a direction normal to the front (in use) face 14.
Bosses 6 for receiving fixing screws are in the second embodiment formed of a different material such as hardened or stainless steel, thereby providing additional security as the bosses 6 are resistant to breakage.
The bosses 6 have a raised part 7 as in the first embodiment for seating in a complementary recess formed in the facing surface of a door or window. The bosses 6 also have a flat 15 which is complementary to a flat in the recess in the door or window and thus acts to prevent rotation of the boss 6 and hence again increases security. In use the monolithic structure of the back plate 10 makes it possible to resist bending or breaking for at least 3 minutes, thereby protecting the lock against attack.
It will be understood that modifications are possible. Thus there may be additional strengthening means in the form of ribs which can be integrally formed with the material of the backing plate 1, 10 and which may extend transversely or longitudinally of the hollowed out part.
These ribs are thus hidden in use, however, they could be formed in addition to, or instead of, such concealed ribs, on a front in use face of the back plate. Also, there could be separate reinforcing means such as reinforcement rods or bars incorporated in the backing plate during manufacture, or which could be applied to the backing plate subsequently, e.g. to extend transversely or longitudinally of the backing plate.
In all embodiments, a backing plate 1 is provided which has been shown to resist attack for 3 minutes or more, so deterring a burglar or thief as the backing plate prevented access to the cylinder lock.

Claims

A backing plate adapted for mounting a handle and with access to a lock, comprising means to resist breakage of the backing plate.
A backing plate according to Claim 1, the means comprising a relatively thick metal backing plate which is adapted to resist breakage.
A backing plate according to Claim 1 or Claim 2, comprising walls of thickness 3mm - 4.5mm, suitably 4.00mm thick.
A backing plate according to Claim 3, the wall being about 4.00mm thick.
A backing plate according to any preceding claim, comprising a unitary workpiece of metal, which is subsequently hollowed out as by machining.
A backing plate according to Claim 5, hollowed out over substantially its whole length.
A backing plate according to Claim 5, comprising a monolithic construction having one or more hollowed out parts.
A backing plate according to any of Claims 5 to 7, formed by being cast in one piece with the required wall thickness.
A backing plate according to any preceding claim, comprising integral ribs, which extend transversely of the length of the backing plate.
A backing plate according to any of Claims 1 to 8, comprising integral ribs which extend across a hollow part of the plate which in use is in abutment with a closure, and/or across a front (in use) surface of the backing plate.
A backing plate according to any preceding claim, the material of the backing plate incorporating separate strengthening means.
A backing plate according to Claim 11, the separate strengthening means comprising rods or bars of reinforced steel which extend longitudinally, or transversely of the backing plate.
A backing plate according to Claim 12, the separate rods or bars being incorporated in the backing plate during manufacture, or subsequently to manufacture.
A backing plate according to any preceding claim, comprising means to mount it on a closure.
A backing plate according to Claim 14, the mounting means comprising bosses each adapted to receive a securing means.
A backing plate according to Claim 15, the bosses being separate steel bosses.
A backing plate according to Claim 16, the bosses comprising a surface profile adapted to resist removal by turning.
A backing plate according to Claim 17, the profile comprising a flat.
A backing plate according to any preceding claim, in combination with a handle and lock.
A door or window, incorporating a combination according to Claim 20.