GB2341417A

GB2341417A - Lock mechanism operating sliding bolt

Info

Publication number: GB2341417A
Application number: GB9819644A
Authority: GB
Inventors: Simon Garth Napthine
Original assignee: Individual
Current assignee: Individual
Priority date: 1998-09-09
Filing date: 1998-09-09
Publication date: 2000-03-15
Also published as: GB9819644D0

Abstract

A lock mechanism comprising a slidable member 3 operated by a standard cylinder 1, or such like, and a lever 4 between the slidable member 3 and the security bolt 6 for increasing the distance moved by the security bolt 6 relative to the slidable member 3.

Description

2341417 LOCK MECHANISM This invention relates to a lock mechanism which

produces a long throw security bolt movement when operated, for example, by a 3601 turn of a key.

Many locks are operated by use of a rotating key which directly or indirectly moves a slidable member within the lock. This slidable member is the..security bolt or is directly attached to it. In some locks the key engages directly with the slidable member during its rotation, other locks make use of lock cylinders. The key is inserted into the lock cylinder and rotates the cylinder cam. This cam engages with the slidable member during its rotation. In either case the distance moved by the security bolt is determined by the arc of rotation of the key or cylinder cam when it is engaged with the slidable member. The maximum straight line movement which can be produced by a 3601 turn of a standard lock cylinder or conventional sized key is approximately 16mm. In some applications a straight line movement greater than this is desireable.

According to the present invention a lever system is included between the slidable member and the security bolt. This lever increases the distance moved by the security bolt relative to the slidable member.

A specific embodiment of the invention will now be described by way of example with reference to the accompanying drawings. Fig. I shows the lock mechanism wi.K-the-security bolt retracted. Fig. 2 shows the lock mechisnism during operation. Fig. 3 shows the lock.opechanism with the security bolt extended. The drawings snow the slidable member being advanced and retracted by a standard lock cylinder. Other methods of moving the slidable member would be,the rotation of a key engaging directly in the recess 12 with suitable warding for security,or the rotation of a suitable cam by a thumbturn, knob or handle.

Referring to the drawings, the standard lock cylinder I has a standard rotating cam 2. As the cam rotates it engages in a recess 12 in the sliding member 3, which it moves until the cam disengages. The sliding member 3, moves the lever 4, to which it is attached by a pivot at 5. This lever is secured b a fixed pivot 7 at one end-and engages with the security 2 bolt 6 at pivot 8. The lever 4 is free to slide within pivots 5 and 7 thus allowing pivot 8 to move in a straight line. Pivot 8 is held in contact with the security bolt 6 by means of a spring 11. The distance moved by the security bolt is greater than the distance moved by the slidable member because pivot 8 is further from pivot 7 than pivot 5 is from pivot 7. A separate commonly used mechanism prevents the security bolt 6 from being retracted by end pressure.

To enable a security bolt to be moved a distance greater than 16mm with a 3600 turn of a standard lock cylinder or conventional sized key, friction within the lock must be kept to a minimum. The example shown in the drawings employs rollers 9 at pivot 8. This reduces the friction between the security bolt 6 and the lock frame 10. This friction is caused by the spring 11 pushing the security bolt 6 against the lock frame 10 via the pivot 8. This reduction in friction could also be achieved by providing rollers attached to the lock frame 10 which bear on the security bolt 6 or rollers attached to the security bolt 6 which bear on the lock frame 10. The example shown also includes rollers 13, 14 and 15. These are attached to the lock frame 10, bear on the sliding member 3 and reduce the friction between the two. This reduction in friction could also be achieved by providing rollers attachedto the sliding member 3 which bear on suitable ledges on the lock frame 10.

3

Claims

1. A lock mechanism comprising a slidable member, means for advancing and retracting the slidable member, and a lever between the slidable member and the security bolt for increasing the distance moved by the security bolt relative to the slidable member.

2. A lock mechanism as claimed in claim 1 wherein the advancing and retracting means comprises a key.

3. A lock mechanism as claimed in claim 1 wherein the advancing and retracting means comprises a standard lock cylinder.

4. A lock mechanism as claimed in claim 1 wherein the advancing and retracting mdans comprises a suitable cam operated by a thumbturn, knob or handle.

5. A lock mechanism as claimed in claim 1, 2, 3 or 4 in which rollers or similar rotating members are attached to the Pivot and bear on the lock frame.

6. A lock mechanism as claimed in claim 1, 2, 3 or 4 in which rollers or similar rotating members are attached to the lock frame and bear on the security bolt.

7. A lock mechanism as claimed in claim 1, 2, 3 or 4 in which rollers or similar rotating members are attached to the security bolt and bear on the lock frame.

8. A lock mechanism as claimed in claim 1, 2, 3 or 4 in which rollers or similar rotating members are attached to the slidable member and bear on the lock frame.

9. A lock mechanism as claimed in claim 1, 2, 3 or 4 in which rollers or similar rotating members are attached to the lock frame and bear on the sliding member.

10. A lock mechanism substantially as described herein with reference to Fig 1 -4 of the accompanying drawings.