GB2220440A

GB2220440A - Remote release of a door security chain

Info

Publication number: GB2220440A
Application number: GB8816381A
Authority: GB
Inventors: Frank Noel Mallett
Original assignee: Individual
Current assignee: Individual
Priority date: 1988-07-09
Filing date: 1988-07-09
Publication date: 1990-01-10
Anticipated expiration: 2008-07-09
Also published as: GB8816381D0; GB2220440B

Abstract

A device for releasing a door security-chain from without the premises, so that the chain 18 may at all times be left in the connected position and only a person having the correct key will be able to gain entry in an emergency. Preferably the chain release mechanism is combined with a conventional lock belt release mechanism. For example, cam 17 provides simultaneous withdrawal of latch bolt 19 and security-chain sliding bolt 14 when cam 17 is rotated by a lock key from outside the closed door. <IMAGE>

Description

REMOTE RELEASE OF A DOOR SECURITY CHAIN This invention relates to the release of a 'Door security -chain' by remote control.

It is well known that nervous persons, particularly the elderly living alone,persist in leaving the security-chain connected at all times; despite being constantly advised that it is unwise to do so, and could mean, and frequently does, that the carer or trusted aent is prevented from entering in an emergency, where the inmate is unable to reach the door. It was just such a occasion . with which the inventor was closely associated, that inspired this invention. The concept of the present invention is essentially the'provision'of a'means of releasing'a security chain from without the premises , or from the opposite side of the door; always having in mind the necessity of keeping the said 'means' in the hands of those havin: the authority to make an entry.

According to the present invention there is provided on one side of the door an ecclosure from which projects a sliding rod that presses against an external stop,the end link of a chain suspended on the projecting en? of the rod would be released by the action of withdrawing the rod into the body of the enclosure, which action would be effected by a key from the opposite side of the door A sDecific embodiment of the invention will now b descried by way of example with reference to the accompanying drawings in which: Figure 1 how the action of the invention as a simple self contain-sd unit, which would be on the insis of the door.

Figure 2 shows a possible developement of the invention to extend the function of a common multi-tumbler-cylinder operated springlatch lock, by combining and synchronizing the actions,of both the lock and that of the invention Referring to the drawings,in Fig.1 the outline of a body 10 encloses a sliding rod 14,a spring 15,and a caml7. exterior to the body 10 is a fixed stop 12,a chain 10 is shown suspended on the projecting end of the rod 14.In the cam 17 a slot 16 i indicated the slot receives a tang (not shown) that connects the cam with a 'multi-tumbler controlled cylinder' of the type so familiarly met in most 'spring-latch'locks that it is not shown).The sid cylinder is set as is normal in the door.

When the cam is rotated in a chlockwise direction the extended eccentric form of the can will prees on the srojection 11 on the rod, and so withdraw the rod into the body, the chain 18 so release will fall clear by gravity.

The chain will be reset b a button (not shown) on the outside of the cover (not shown) of the body 10, moving in line with and engaging with the sliding rod 14,so that the rod may be withdrawn into the body and the chain reset.

Should the occupant wish to open the door fully. there wil be no need to release the 'Remote - release', the chain can just as normally be unhooked from the'key-hole'slot that will not be oZl the architrave or adjacent thereto.

In Rig.2 the invention 'virtually' in the same form as shown in Sigl. is here extended and enhanced by it's inclusion with, and in combination with,the action of a simple spring-latch lock 19, both being governed by the same cam 17,and the one key, so that the carer or agent can effect a simultaneous and immediate release of the chain and the latch. It will be seen that the simultaneity is effected by the cam having two extended eccentric forms equidistant from the rotation centre of the cam 17. the compression spring 15 maintains a reciprocal opposing pressure on the latch-bolt and the sliding rod 14.

The Din 13 prevents the cam being turned in the wrong direction.

The Fig.3 is a side elevation of the body from the direction of the arro-: 2D, showing the end link of the chain 13 in the set position.

The customary locking snib, will be slightly modified to ensure that the spring-latch cannot be locked in the closed position.

Claims

CLADIS

1 A remote release of a security-chain, that will enable a carer or trusted agent to gain immediate entry,when the chain is in the security-connected situation.

2 A remote release of a security-chain, as claimed in Claim 1 wherein the means of achieving a'remote release' is contained in an individual self-contained unit that can be mounted

separately from and notwithstanding any other lock systems that may be'in situ'.

3 A remote release of a security-chain, as claimed in Claim 1 or Claim 2 wherein the means of extending.advancing , and enhancing the advantages of the invention as claimed in Claim 1 or Claim 2,can be by combining the mechanical action of the invention with the action of a universal or common niulti-tumbler -cylinder controlled door lock.

4 A remote release of a security-chain, substantially as described herein with reference to Figures 1-3 of the accompanying drawings.

A A remote release of a security-chain, as claimed in any preceding claim , wherein any attempt to gain unlawful entry by manually manipulating the spring-latch, with say, a piece of 'plastic', is defeated by the independence of the action of the releasing'sliding rod'from the action of the spring-latch,when the cam is not used.