GB2064638A

GB2064638A - Security Sealing of Locks

Info

Publication number: GB2064638A
Application number: GB8038091A
Authority: GB
Original assignee: EVOPAK Ltd
Current assignee: EVOPAK Ltd
Priority date: 1979-12-05
Filing date: 1980-11-27
Publication date: 1981-06-17
Also published as: GB2064638B

Abstract

A device for the security sealing of a key-operated lock comprises a first member (5) which is permanently attached or attachable adjacent the keyhole (4) of the lock. This first member at least partly defines a chamber (5a). A second member (6) is disposable and adapted to have a part (6a) non-removably inserted into the chamber (5a) through an opening (5b) therein so as to assume a position in which a part (6b) of the disposable member (6) situated outside the chamber (5a), covers a keyhole (4). The device is then effective until the part (6b) of the disposable element (6) outside the chamber (5a) is ruptured from the part (6a) of the disposable element (6) situated within the chamber (5a). <IMAGE>

Description

SPECIFICATION Security Sealing of Locks This invention relates to the security sealing of locks.

The security of a key-operated lock depends not only upon its ability to resist unlocking by use of tools inserted by way of the keyhole but more importantly upon permanent possession of the lock key by the person authorised to operate the lock. It will readily be realised that if a key is lost, stolen or temporarily appropriated, with or without the authorised keyholder's knowledge, so that it can be used or duplicated by an unauthorised person, all security is lost until the lock can be replaced.

The present invention has accordingly been devised with the object of protecting keyoperated locks against unauthorised operation or interference and further of signifying whether any such unauthorised operation or interference has occurred.

In accordance with the present invention a device for the security sealing of a key-operated lock comprising a first member which is attachable to the lock around the lock keyhole and which at least partly defines a seal chamber; and a second member which is disposable and adapted to be partially inserted into the seal chamber so as to assume a position in which access to the keyhole is prevented until a part of the second member which is outside the chamber is ruptured from the part of the disposable second element situated within the chamber.

The first member may thus preferably comprise a plate affixable over the outside face of the lock.

This plate casing may form one element of a casing which surrounds the keyhole or the body part of a padlock, the casing having a hinged cover secured in a closed position on the said element by the disposable member.

The disposable member preferably comprises a somewhat resilient plate made of synthetic plastics material which is of resilient arrow-head formation at one end and has a tab at the other end. The chamber in the first member has an opening in its side nearest the keyhole and the dimensions of this opening are such as to permit entrance and yet deny withdrawal of the arrowhead formation.

It is to be understood that entrance is a consequence of the squeezing together of the arrowhead sides which by subsequently resuming their former outward positions resist subsequent withdrawal. There is a zone of weakness at the junction between the arrowhead formation and the tab. When an authorised lock user wishes to insert a key in the keyhole the tab has to be broken away from the arrowhead formation at the weakness zone. This is accomplished manually or by outward levering action of a thin blade inserted between the keyhole and the tab until breakage occurs. The chamber is provided with an opening to permit escape of the supernumerary severed arrowhead part from the chamber in order that there shall be no obstacle to the insertion of a fresh disposable member after the lock has been re-locked.

Typical embodiments of the invention are illustrated in the accompanying drawing wherein Figs. 1 and 2 are fragmentary perspective views of a keyhole security sealing device respectively before and after being rendered operative: Figs. 3 and 4 are perspective views of a second embodiment including a hinged cover; and Figs. 5 and 6 are perspective views of a variation of the second embodiment.

Figs. 1 and 2 show a device in accordance with the invention being used in conjunction with a key-operated mortise lock 1 fitted in a door 2. The lock 1 has an escutcheon plate 3 fitted against the door 2 and having a keyhole 4 therein.

Surrounding about threequarters of the periphery of this plate 3 is a fixed part-circular plate 5 of which the part 5a furthest from the door edge defines an internal chamber with an entrance 5b of rectanguiar shape. This chamber has an exit opening (not shown) in its underside.The central front part of the casing 5 is cut away so as to expose the keyhole 4 and provide a guide path for slidably receiving and locating a disposable sealing member 6 which is made of somewhat resilient plastics material and comprised of an arrowhead formation part 6a, intended to be nonwithdrawably inserted through the entrance 5b into the chamber 5a, and a tab 6b which is shaped and dimensioned so as to be slidably receivable within the cut away part of the casing and movable to the position shown in Fig. 2, wherein it totally covers the keyhole 4 and renders it inaccessible to a key or other tool.

The keyhole 4 can now only become accessible by causing fracture of the sealing member at the junction between the arrowhead formation part 6a and the tab 6b. This can be accomplished most easily by inserting a thin blade between the tab and the escutcheon plate 3 and applying outward leverage. After fracture has occurred the now separate arrowhead formation part drops through the already mentioned exit opening in the chamber.

Referring now to Figs. 3 and 4, the device therein shown differs mainly from that of Figs. 1 and 2 by the provision of a two-part casing consisting of a substantially rectangular base plate 10 with a hinged cover 11. The base plate 10 is secured to the lock mounting, e.g. a door, by four screws and is centrally apertured to expose the escutcheon 3 and keyhole 4. To one side of the central aperture is a frame structure 12 which is open at the top and the bottom and which forms part of a chamber intended non-removably to receive a disposable plastics material sealing element 6 as previously described. The remainder of this chamber is formed by a hollow protrusion 13 on the cover 1 The protrusion 13 has a slot 1 3a in its underside for admitting the narrow head of a sealing element 6.The mode of functioning of the device should be readily apparent particularly from Fig. 4 where the final position of the tab 6b is indicated in dashed lines.

Figs. 5 and 6 show essentially the same device as is illustrated in Figs. 3 and 4 but modified for the security sealing of a padlock. It thus comprises a casing base part 14 which is of boxlike form in order to contain the body 1 5 of the padlock. The base part 14 has two holes in its upper wall for accommodating the legs of the padlock hasp 1 6 and likewise the upper wall of the hinged cover 11 has two recesses for the same purpose. The hasp 1 6 is of course rotatable relative to the body 1 5 when the padlock is unlocked so that it is readily insertable into or removable from the device in that condition.

The padlock shown has a front keyhole 4 but it will be readily understood that if it was of a type having a keyhole in its base it would be necessary to provide the lower wall of the casing base 14 with a key access hole which of course would be covered by the lower wall of the cover 11 when the latter is closed over the base 14. The mode of operation of this device is as previously described for the two already described embodiments.

As a further adjunct to security, with all forms of the device, the disposable sealing members, which will at all times only be in the possession of the authorised user - and kept separate from the lock - may be serially numbered or coded.

The device can be used with a wide variety of locks to provide a high degree of lock security.

Among such locks there is additionally mentioned those which secure coin collecting boxes in slot machines of all kinds. The device moreover is easy to use and cheap to produce.

Claims

1. A device for the security sealing of a keyoperated lock comprising a first member which is attachable to the lock around the lock keyhole and which at least partly defines a seal chamber; and a second member which is disposable and adapted to be partially inserted into the seal chamber so as to assume a position in which access to the keyhole is prevented until a part of the second member which is outside the chamber is ruptured from the part of the disposable second element situated within the chamber.

2. A device in accordance with claim 1 wherein the first member is a plate which is affixable to the lock mounting and the said chamber is laterally offset relative to the keyhole, the part of said second member outside said chamber being shaped to cover the said keyhole when the remainder of the said second member is inside said chamber.

3. A device in accordance with claim 1 wherein said first member is a plate which is affixable to the lock mounting and has a hinged cover, the said chamber being formed by a structure on said plate and by a hollow protrusion of thecover, the cover being maintained in its closed keyholecovering position over the plate by means of the disposable second member until the latter is ruptured as aforesaid.

4. A device in accordance with claim 1 in which said first member is a casing adapted to contain the body of a padlock and has a hinged cover adapted when closed to cover the padlock keyhole, the said chamber being formed by an internal structure in said casing and by a hollow protrusion of the hinged cover, and the cover being maintained in its closed position over the casing by means of the disposable second member until the latter is ruptured as aforesaid.

5. A device in accordance with any of claims 1 to 4 wherein the disposable member comprises a plate which is of resilient arrowhead formation at one end and has a tab at the other end, said chamber having an opening in its side and the dimensions of this opening being such as to permit entrance and yet deny reverse withdrawal of the arrowhead formation, said disposable member being rupturable at the junction between the arrowhead formation and the tab.

6. A device for the security sealing of a key operated lock constructed and adapted to operate substantially as hereinbefore described with reference to and as shown in any of Figures 1 and 2, Figures 3 and 4 or Figures 5 and 6 of the accompanying drawings.