NZ537792A - A lock having a cylinder attached in a particular manner - Google Patents

Abstract

A lock has a locking block which can move between a locking position and a unlocking position, a cylinder cam that causes the locking block to move between its said positions, a cylinder cam stop member that limits the degree of rotation of the cylinder cam, the cylinder cam stop member being movable between a stop position where the degree of rotation of the cylinder cam is limited, and a free position where the cylinder cam can rotate further, and locking means to lock the cylinder cam stop member into the stop position. Thus, as the reason for unlocking the stop member would typically be to remove the cylinder (containing the cylinder cam) from the lock, it is efficient to make the locking means "dual purpose" by having the locking means locking the cylinder in the lock as well as locking the stop member in place.

Description

* 7 7 9 2 intellectual property office! of i\l.z 19 jan 2005 Received 1 A Lock Having a Cylinder Attached in a Particular Manner Field of the Invention This invention is directed to a lock and is particularly directed to a lock 5 of the type that has a locking block or dead bolt which is moved by a cylinder cam lock and where the cylinder that contains the cylinder cam can be fitted to the lock in a more convenient manner.

Background Art Many locks are now provided with a dead bolt or locking block. The 10 dead bolt can move between a deadlock position and a free position. In the deadlock position, a nose portion of the dead bolt engages with the main lock tongue to prevent the main lock tongue from being retracted. In the free position, the main lock tongue is free to move between its retracted and extended positions. The dead bolt is moved by a cylinder cam which has a small extending arm member which engages in a recess 15 on the dead bolt. Rotation of the cylinder cam causes the small extending arm member to push the dead bolt into the locking position or to pull the dead bolt into the free position. The cam can rotate either clockwise or anticlockwise by engagement with a pin which extends from the back of a key cylinder. This pin is rotated upon insertion and rotation of a key into the key cylinder. The key cylinder may comprise two key 2 0 cylinders to enable the key to be inserted and to operate the cam either from the front of the lock or the rear of the lock. Alternatively, the cylinder may comprise a single cylinder to enable a key to operate the cam from only one side of the lock. The above arrangement is very well-known in the marketplace.

Some of these locks are provided with a fixed cam, which is a cam 2 5 which does not have any "lost motion". In the past, there have been some difficulties in assembling the cylinder into the lock. This comes about because it is necessary to ensure that the cam does not lose its synchronisation with the deadlock (this means that the cam must be positioned such that the short extending arm member sits in the recess of the deadlock). Thus, it is sometimes necessary to insert a key into the 3 0 cylinder during assembly of the cylinder. Sometimes, it is necessary to provide additional cutouts in the lock body to assemble the cylinder, and this can be a disadvantage in the fabrication of the lock.

It will be clearly understood that, if a prior art publication is referred to herein, this reference does not constitute an admission that the publication forms part of the common general knowledge in the art in Australia or in any other country.

Object of the Invention It is an object of the invention to provide a lock that may overcome at least some of the above-mentioned disadvantages or provide a useful or commercial choice.

In one form, the invention resides in a lock, the lock having a locking block which can move between a locking position and a unlocking position, a cylinder cam that causes the locking block to move between its said positions, a cylinder cam stop member that limits the degree of rotation of the cylinder cam, the cylinder cam stop member being movable between a stop position where the degree of rotation of the cylinder cam is limited, and a free position where the cylinder cam can rotate further, and locking means to lock the cylinder cam stop member into the stop position.

Thus, the cylinder cam which operates the locking block (which can be a deadlock) is held against excessive rotation by the cylinder cam stop member. However, the cylinder cam stop member can be moved to enable the cylinder cam to rotate further for instance, to allow the cylinder cam to be removed from the lock. However, the cylinder cam stop member is normally locked against movement by the locking means, but the locking means can be removed to allow the cylinder cam stop member to be moved if necessary (for instance, to enable the key cylinder containing the cylinder cam to be removed or inserted from the lock).

The lock may be any suitable type of lock and no particular limitation is to be placed on the type of lock. Typically, the lock will have a main latch tongue that can reciprocate or rotate between an extended and retracted position. The main latch tongue may be provided with serrations, bevels or may have any suitable configuration. If desired, an auxiliary latch tongue may be provided.

The locking block may comprise an elongate member that can move (typically sliding movement) between a locking position and a free position. In the locking position, the locking block will typically prevent retraction of the lock tongue although it is envisaged that the locking block may also engage with other components of the lock, or indirectly with the lock tongue. The locking block may comprise a solid member, a hollow member, a plate like member, and may be made of any suitable material such as metal, alloys, plastics, composite materials and the like. The locking block may be formed of a single piece of material, a plurality of pieces of material and the like. No particular limitation should be placed on the term "locking block".

The cylinder cam may be of conventional design and may comprise a substantially disk like member containing a short extending arm portion or projection that engages either directly or indirectly with the locking block. The cylinder cam will typically be positioned on the rear of the cylinder in the normal manner. However, the cylinder cam may comprise other shapes and configurations providing that the cam 10 operates the locking block either in a direct or indirect manner. Therefore, no particular limitation should be placed on how the cylinder cam engages with the locking block.

The lock contains a cylinder cam stop member (hereinafter called a stop member) which functions to limit the degree of rotation of the cylinder cam. The 15 stop member may do so either by directly engaging with the cylinder cam, indirectly engaging with the cylinder cam or otherwise functioning to limit the degree of rotation of the cylinder cam.

The stop member may comprise a separate part that is assembled into the lock during the assembly process. The part may have a first portion that engages 2 0 with the cylinder cam and typically engages with the small arm member or projection on the cylinder cam to prevent over rotation of the cylinder cam.

The stop member may be provided with a small projection that engages in an opening to position the stop member in the lock body.

It is preferred that the stop member can pivot or move between a first 25 position where it functions to stop over rotation of the cam member and a second position where the cam member can rotate further.

It is preferred that the stop member is biased into the first position where it prevents over rotation of the cylinder cam. A biasing means may be provided to bias the stop member. The biasing means may comprise a spring or any other type 30 of biasing member. The biasing means may be provided between an internal wall of the lock and the stop member.

The stop member may be made of a single piece of material, a plurality of pieces of material and may be made of any suitable material such as metal, alloys, plastics composite materials and the like.

The locking means functions to lock the stop member into the stop position which is where it prevents over rotation of the cylinder cam. The locking means may comprise a fastener. The fastener may comprise a screw fastener. The 5 screw fastener may have a further purpose of attaching the cylinder to the lock. Thus, as the reason for unlocking the stop member would typically be to remove the cylinder (containing the cylinder cam) from the lock, it is efficient to make the locking means "dual purpose "by having the locking means locking the cylinder in the lock as well as locking the stop member in place. No particular limitation should be placed on the 10 shape and configuration and positioning of the locking means.

Brief Description of the Drawings An embodiment of the invention will be described with reference to the following drawings in which: Figure 1. Illustrates part of the internal components of a lock and particularly 15 illustrate the components of the lock that form part of the present invention.

Figure 2. Illustrates the locking means and the cylinder cam but has the cylinder cam stop member removed.

Figure 3. Illustrates the other side of the lock.

Figure 4. Illustrates the lock containing the locking block and illustrating how 2 0 the locking block is driven by the cylinder cam.

Best Mode Referring to the drawings and initially to figure 4, there is illustrated the lower part of a lock which contains a locking block 10. Referring to figures 1-3, the locking block 10 has been removed to better illustrate the other components. 25 Referring specifically to figure 1, this illustrates the other components of the lock and which form part of the present invention, these components being a cylinder cam 11, a cylinder cam stop member 12, and a locking means 13.

The lock itself will typically be of conventional design and will typically contain a reciprocating main lock tongue. In the lower part of the lock is the 3 0 locking block 10 (see figure 4) which functions to deadlock the main lock tongue.

Locking block 10 will typically comprise a solid metal member which is generally elongate and which has a rear portion 14 (see figure 4) and a front nose portion (not illustrated) but which engages with the main lock tongue in a known manner. The rear portion of locking block 10 contains a recess 15 to enable the cylinder cam 11 to engage with and to move the locking block 10. Specifically, cylinder cam 11 is disk like and generally circular but has a small extending arm portion 16 which sits partially inside recess 15. Rotation of cylinder cam 11 in a clockwise direction (with 5 reference to figure 4) will cause locking block 10 to move upwardly and into the deadlocking position, and rotation of cylinder cam 11 in an anticlockwise direction will cause locking block 10 to move downwardly and into the free position. When in the deadlocking position, locking block 10 has been moved forwardly by a small distance (typically about 10 millimetres) but this is sufficient for part 17 of locking block 10 (again see figure 4) to now be in front of part 18 of the lock housing, and locking block 10 is biased by a small spring (not illustrated but of conventional design) in the direction of arrow 19 which causes part 17 to overlie part 18 when the locking block 10 is in the forward locking position and this prevents the locking block from inadvertently being forced back into the unlocking position. The locking block 10 can only move to the retracted free position by rotation of cylinder cam 11. This arrangement is known, but has been described to illustrate that cylinder cam 11 and especially the small arm portion 16 needs to be within recess 15 for the locking block to operate properly. Therefore, any assembly of the cylinder which causes misalignment of cylinder cam 11 can also cause the lock to not operate properly. 2 0 Cylinder cam 11 is caused to rotate by a cylinder (not illustrated but of conventional design) which extends through an opening 20 in the lock body. The cylinder will have a small rotating pin on the bottom thereof which engages with cylinder cam 11. When a key is inserted into the cylinder and turned, this will turn the small rotating pin which will turn cylinder cam 11 either clockwise or anticlockwise. 2 5 Again, this is known.

Referring now to figure 1, there is illustrated a cylinder cam stop member 12 which sits underneath the locking block 10 and therefore locking block 10 has been removed in figure 1. Cylinder cam stop member 12 (hereinafter called stop member 12) is a separate member that is assembled during assembly of the lock. Stop 3 0 member 12 contains an extending leg portion 21 which contains a small depending pin 22 the pin being best illustrated in figure 3. Pin 22 sits within an elongated aperture 23 and the reason for having the elongated aperture 23 will be described in greater detail below. Stop member 12 contains another abutment portion 24 which engages with cylinder cam 11. Cylinder cam 11 is unable to rotate in a clockwise manner past abutment portion 24. Therefore, the abutment portion restricts cylinder cam 11 to operating within a predetermined angular movement. Abutment portion 24 is biased into engagement with cylinder cam 11 by a small spring 25.

The design of stop member 12 and particularly the design of abutment portion 24 is such that the small arm portion 16 only just engages with abutment portion 24. Moreover, stop member 12 is able to move upwardly in the direction of arrow 26 and this is permitted because of the elongate opening 23 which contains pin 22. The degree of movement is not great (typically only a few millimetres) but is sufficient to allow cylinder cam 11 to push stop member 12 upwardly thereby allowing the cylinder cam 11 to rotate past abutment portion 24. When this happens, cylinder cam 11 can rotate to a position that allows the cylinder to be removed from the lock. That is, the arm portion 16 overlies opening 20 that enables removal of the entire cylinder.

Movement of stop member is however prevented by a locking means 13. In the particular embodiment, locking means 13 is the cylinder mounting screw. The cylinder mounting screw normally functions to screw the cylinder into the lock body. The cylinder mounting screw is typically inserted through a front edge of the lock as this edge is not accessible for tampering when the door or window is closed. In 2 0 the particular embodiment, the cylinder mounting screw also functions as the locking means and this is achieved by having the cylinder mounting screw extending over the top of stop member 12. Stop member 12 is provided with an abutment 30 which abuts against the cylinder mounting screw (see figure 1) and this prevents stop member 12 from moving upwardly by the few millimetres. Thus, as long as the cylinder mounting 2 5 screw is in the position illustrated in figure 1, stop member 12 functions to prevent over rotation of cylinder cam 11.

However, if it is desired to remove the cylinder or to insert a cylinder, the cylinder screw is removed and this allows stop member 12 to be moved.

Throughout the specification and the claims (if present), unless the 3 0 context requires otherwise, the term "comprise", or variations such as "comprises" or "comprising", will be understood to apply the inclusion of the stated integer or group of integers but not the exclusion of any other integer or group of integers.

Throughout the specification and claims (if present), unless the context requires otherwise, the term "substantially" or "about" will be understood to not be limited to the value for the range qualified by the terms.

It should be appreciated that various other changes and modifications can be made to any embodiment described without departing from the spirit and scope of the invention. 8

Claims (14)

Claims:

1. A lock having a locking block which can move between a locking position and a unlocking position, a cylinder cam that causes the locking block to move between its said positions, a cylinder cam stop member that limits the degree of 5 rotation of the cylinder cam, the cylinder cam stop member being movable between a stop position where the degree of rotation of the cylinder cam is limited, and a free position where the cylinder cam can rotate further, and locking means to lock the cylinder cam stop member into the stop position.

2. The lock of claim 1, which has a main latch tongue that can reciprocate 10 or rotate between an extended and retracted position.

3. The lock as claimed in any one of the preceding claims, wherein the locking block comprises an elongate member that can move between a locking position and a free position.

4. The lock of claim 3, wherein the locking block, when in the locking 15 position prevents retraction of the lock tongue.

5. The lock as claimed in any one of the preceding claims, wherein the cylinder cam comprises a substantially disk like member containing a short extending arm portion that engages either directly or indirectly with the locking block.

6. The lock as claimed in any one of the preceding claims, wherein the 2 0 cylinder cam stop member comprises a separate part that is assembled into the lock during the assembly process.

7. The lock of claim 6, wherein the separate part has a first portion that engages with the cylinder cam and engages with the small arm member or projection on the cylinder cam to prevent over rotation of the cylinder cam. 25

8. The lock as claimed in any one of the preceding claims, wherein the cylinder cam stop member has a small projection that engages in an opening to position the stop member in the lock body.

9. The lock as claimed in any one of the preceding claims, wherein the stop member is moveable between a first position where it functions to stop over 3 0 rotation of the cam member and a second position where the cam member can rotate further.

10. The lock as claimed in claim 9, wherein the stop member is biased into the first position. intellectual property office of n.z 2 6 jul 2005

11. The lock of claim 10, wherein the stop member is biased by a spring provided between an internal wall of the lock and the stop member.

12. The lock as claimed in any one of the preceding claims, wherein the locking means comprises a fastener.

13. The lock of claim 12, wherein the fastener comprises a screw fastener which also attaches a key cylinder to the lock.

14. A lock substantially as hereinbefore described with reference to the illustrations. intellectual property office OF N.7. 1 26 JUL 2005