GB1582715A - Door stop mechanisms - Google Patents

Description

(54) IM0VEMENTS IN AND RELATING TO DOOR STOP MECHANISMS (71) We, JOHN TANN SEcUBITY LIMITED, a British Company, of Stirling Corner, Borehamwood, Hertfordshire, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: Thi & invention relates to improvements in and relating to door stop mechanisms more especially mechanisms for the doors of inter alia safes and strongrooms.

In recerit armed robbery the door of a strongroom having been legitimately opened the person opening the door has been placed incommunicado within the strongroom, the door having been closed upon him.

According to the present invention the above situation is avoided by providing a door stop mechanism for attachment to the intermediate surrounding structure of a door, said mechanism comprising a door rod and a co-operating lock bolt, the door rod being continuously slidably urged in a linear path so that one of its end faces abuts with the inside of the door when closed and moves with said door over the initial part of the opening movement the said lock bolt being so placed after said initial part of the opening movement to prevent the return of the door rod and the closure of the door until said lock bolt is removed from said linear path by time delay means.

The extended lock bolt may conveniently be withdrawn to allow reclosure of the door either by the use of a delay means such as a key not readily available to the person or persons opening the door or by an electronic or a mechanical time delay mechanism.

The invention will be more fully understood from the following description given by way of example only in respect of the figures of the accompanying drawing in which:- Figures l and 2 are elevations in third angle orthographic proejction of a door mechanism of the invention.

Referring specifically to the figures of the drawing ra plate 10 having fixing holes 10i- 1OjT is adapted to be attached to the immediate surrounding structure (not shown) of a door 19. The plate 10 carries a door rod 11 that is able to slide in lugs 122.121 and to be continuously spring urged in à linear path in the direction of arrow X by a helical compression spring 13 that co-operates with a pin 14 that passes through the door rod 11. The door rod 11 has an integral collar 11C. A lock bolt 15 is shown extended so that it is able to resist any return movement of the door rod ii in the direction of arrow Y since the end 1 IA of door rod 11 is juxtaposed with face 15A of the lock bolt 15.

Lock bolt 15 can be withdrawn from the extended position only by means of a key (not shown that is not readily available to the person or persons opening the door) that is used to actuate lock 16 via key slot 161.

A catch 17 provided with a stud 171 is arranged to hold the lock bolt 15 in the lock 16 when the key is withdrawn and the door rod 11 is in the outwardly extended position shown in Figure 1 since the lock bolt 15 is permanently urged by means (not shown) in the direction of arrow Z to its extended position. The catch and stud 171 are actuated by the end 11A of the door rod 11 to move it from the position shown in full lines in Figure 1 to the position shown in dotted lines when the door is closed and once again free the bolt 15 so that it abuts surface 11D of rod 11 ready for the next opening of the door.

The mods operandi of the door mechanism described above is as follows: Consider the plate 10 fixed either to a side wall 18 or to the roof of a strongroom denoted by chain dotted lines and a door 19 of width d1 that closes thereto. When the door 19 is closed to side wall 18 the face 11B of door rod 11 is at 11B1 against the door 19 per se and the collar 11C moves in close to lug 121 against the spring presesure of spring 13 which is compressed; further the end llA of door rod 11 is at position 1 1A1 underneath the raised lock bolt 15 (which position is not shown) such that face 15B of lock bolt 15 abuts with the surface llD of the door rod 11.When the door 19 is opened the door rod 11 moves out with it in the direction of arrow X under spring force generated by the spring 13. When the surface 11D of the door rod 11 moves out of contact with face 15B of the lock bolt 15 it extends itself to the position shown in Figures 1 and 2 and clearly the door rod 11 cannot now be moved in the direction of arrow Y since face 11A of the door rod 11 and face 15A of the lock bolt 15 are juxtaposed. Thus the door 19 cannot be reclosed unless a key is provided to withdraw lock bolt 15. It is now but a matter of security discipline and routine to see that no one opening the strongroom door 19 has access to the key that fits key slot 161.

Clearly, the withdrawal of lock bolt 15 may be regulated by an electronic or mechanical time delay mechanism (not shown) that permits reclosure of the door after a period of several minutes, which period is adjustable to allow it to exceed any period thought to be reasonable and totally unacceptable to a robber. Again an obturator plate may be used to block the key slot 16l and this plate may be under the control of a time delay mechanism. Yet again a time delay actuated mechanism independent of lock bolt 15 may be used to co-operate with door rod 11 and prevent its return and prevent the reclosure of the door.

WHAT WE CLAIM IS:- 1. A door stop mechanism for attachment to the immediate surrounding structure of a door, said mechanism comprising a door rod and a co-operating lock bolt, the door rod being continuously slidably urged in a linear path so that one of its end faces abuts with the inside of the door when closed and moves with said door over the initial part of its opening movement, the said lock bolt being so placed after said initial part of the opening movement to prevent the return of the door rod and the closure of the door until said lock bolt is removed from said linear path by time delay means.

2. The door stop mechanism according to claim 1, wherein said time delay means is a key not readily available to the person or persons opening the door.

3. The door stop mechanism according to claim 1, wherein said time delay means is a mechanical mechanism.

4. The door stop mechanism according to claim 1, wherein said time delay means is an electronically actuated mechanism.

5. The door stop mechanism according to claim 1, wherein said time delay means is an obturator plate that covers and uncovers a key slot.

6. The door stop mechanism according to any preceding claim wherein the door rod is slideably urged by a helical compression spring.

7. A door stop mechanism constructed and adapted to operate substantially as described herein and shown in the figures of the drawing that accompanied the Provisional Specification.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (7)

**WARNING** start of CLMS field may overlap end of DESC **. side wall 18 or to the roof of a strongroom denoted by chain dotted lines and a door 19 of width d1 that closes thereto. When the door 19 is closed to side wall 18 the face 11B of door rod 11 is at 11B1 against the door 19 per se and the collar 11C moves in close to lug 121 against the spring presesure of spring 13 which is compressed; further the end llA of door rod 11 is at position 1 1A1 underneath the raised lock bolt 15 (which position is not shown) such that face 15B of lock bolt 15 abuts with the surface llD of the door rod 11. When the door 19 is opened the door rod 11 moves out with it in the direction of arrow X under spring force generated by the spring 13.When the surface 11D of the door rod 11 moves out of contact with face 15B of the lock bolt 15 it extends itself to the position shown in Figures 1 and 2 and clearly the door rod 11 cannot now be moved in the direction of arrow Y since face 11A of the door rod 11 and face 15A of the lock bolt 15 are juxtaposed. Thus the door 19 cannot be reclosed unless a key is provided to withdraw lock bolt 15. It is now but a matter of security discipline and routine to see that no one opening the strongroom door 19 has access to the key that fits key slot 161. Clearly, the withdrawal of lock bolt 15 may be regulated by an electronic or mechanical time delay mechanism (not shown) that permits reclosure of the door after a period of several minutes, which period is adjustable to allow it to exceed any period thought to be reasonable and totally unacceptable to a robber. Again an obturator plate may be used to block the key slot 16l and this plate may be under the control of a time delay mechanism. Yet again a time delay actuated mechanism independent of lock bolt 15 may be used to co-operate with door rod 11 and prevent its return and prevent the reclosure of the door. WHAT WE CLAIM IS:-

1. A door stop mechanism for attachment to the immediate surrounding structure of a door, said mechanism comprising a door rod and a co-operating lock bolt, the door rod being continuously slidably urged in a linear path so that one of its end faces abuts with the inside of the door when closed and moves with said door over the initial part of its opening movement, the said lock bolt being so placed after said initial part of the opening movement to prevent the return of the door rod and the closure of the door until said lock bolt is removed from said linear path by time delay means.

2. The door stop mechanism according to claim 1, wherein said time delay means is a key not readily available to the person or persons opening the door.

3. The door stop mechanism according to claim 1, wherein said time delay means is a mechanical mechanism.

4. The door stop mechanism according to claim 1, wherein said time delay means is an electronically actuated mechanism.

5. The door stop mechanism according to claim 1, wherein said time delay means is an obturator plate that covers and uncovers a key slot.

6. The door stop mechanism according to any preceding claim wherein the door rod is slideably urged by a helical compression spring.

7. A door stop mechanism constructed and adapted to operate substantially as described herein and shown in the figures of the drawing that accompanied the Provisional Specification.