NZ548437A - Improvements relating to locks - Google Patents

Abstract

A key K and lock 10 with a spacer element 14 attached to the plug of the lock are disclosed. The spacer element 14 cooperates with a shoulder S of a key K to enable that key to operate the lock. When the spacer element is detached from the plug, the key if inserted does not align properly with the lock. The system is disclosed to be particularly suited to locks with construction keying.

Description

4 84 37 0056649099^ OurRef: AAN003NZ Patents Form No. 5 PATENTS ACT 1953 Complete After Provisional No: 548437 Filed: 11 July 2006 COMPLETE SPECIFICATION IMPROVEMENTS RELATING TO LOCKS We, Assa Abloy New Zealand Limited, a New Zealand company of 6 Armstrong Road, North Harbour Industrial Estate, Albany, Auckland 0632, New Zealand, 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: Intellectual Property """"1 Office of N.Z. 1 1 1 JUL 2007 _RECEIVED , IMPROVEMENTS RELATING TO LOCKS FIELD OF THE INVENTION This invention relates to improvements relating to locks and more particularly to a lock and key system.

SUMMARY OF THE INVENTION "So called construction keying" of locks is known in the art. The construction keying of locks provides a convenient way of allowing contractors, builders, trades people and the like to enter a building during the construction phase. To achieve construction keying a door or window lock is arranged so that once a building owner's key (so called servant key) is inserted into the lock the construction keying is 15 automatically deactivated. As a result all subsequent operations of the lock can only be effected by the servant key.

Construction keying is thus effectively a particular form of master keying. In this way construction workers can gain entry to a building during the construction period 20 but when the building owner takes possession of the building and uses the servant keys in construction keyed cylinders the "construction mode" of the cylinder is deactivated.

Accordingly, it is important that during the construction phase the servant keys not 25 be used otherwise the "construction mode" is deactivated. Such deactivation prevents construction workers from gaining access to the building by way of the construction key. The deactivation of the "construction mode" if the deactivation takes place before the construction phase of the building has been completed therefore creates great inconvenience. This can lead to delays and increased costs. 2 Because of the unusual form of master keying in order to achieve construction keying of the lock cylinder there are a limited number of unique construction key codes. The lock manufacturer will therefore assign a key code to a door/window fabricator and/or builder though it will generally be the fabricator who will be 5 assigned the construction key code. The fabricator will then supply construction keyed doors and windows (usually locked) to the builder.

At the time of providing a construction key code to a fabricator the lock manufacturer will provide a limited number of keys. The fabricator can, however, 10 order additional construction keys from the lock manufacturer. If the construction key is based on a common key profile the fabricator and indeed builder, construction site workers etc can have duplicate keys cut anywhere.

Situations can arise where a builder may purchase doors and windows from a 15 number of different fabricators. This might not necessarily be windows and doors for a particular single building but for a number of buildings being built at any one time by the builder. Consequently builders and their workers, sub-corrtractors etc will carry or be supplied with a variety of construction keys to enable access to be gained to various buildings under construction. As a consequence many different 20 categories of people involved in the building industry may carry or have access to large numbers of construction, servant and simple KA keys. The overall result is that those involved in the construction industry in the normal course of events have access to and/or possession of a wide range of construction, servant and other keys.

This wide disbursement of keys and the proliferation of duplicates of construction keys has an overall effect of weakening the security of the construction/servant key system. This proliferation of keys is not confined solely to construction keys as servant keys for locks will usually be based on common key profiles. Thus builders and workers as well as sub-contractors who have access to servant keys can also 30 have these duplicated by any key cutting service. 3 As a result fabricators, builders, sub-contractors and the like can collect and retain copies of various construction keys and KA keys not to mention servant keys that these people have handled during many building projects. Therefore there is the 5 potential for and indeed actual occasions of systematic use of these keys in a construction keyed cylinders in order to falsely operate locks and provide access (unauthorised) to a building. Therefore the integrity of the convenient security of buildings under construction by use of construction keying can be adversely affected.

In view of the foregoing the object of the present invention is to provide a lock and key system which provides the convenience of construction keying yet with improved security, or at least to provide the public with a useful choice.

SUMMARY OF THE INVENTION A first aspect of the invention provides a lock and key system including a spacer element detachably coupled to a plug of a lock, the spacer element having an aperture aligned with a key slot in the plug, and a key having a datum surface which 20 enables the lock to be operated by the key when the spacer element is coupled to the plug but not when the spacer element has been detached therefrom.

A second aspect of the invention provides a key-operable lock including a plug with a key slot to receive a key for operation of the lock, and a spacer element detachably 25 coupled to the plug, said spacer element having an aperture aligned with the key slot to enable a first key to be inserted into the plug to effect operation of the lock.

A third aspect of the invention provides a spacer element configured for detachable coupling to a plug of a key-operable lock and having an aperture which, in use, 30 aligns with a key slot in such a lock so as to allow a key to be inserted into the lock, 4 the spacer element having a predetermined thickness so as to cooperate with a datum surface of a key to enable lock operation.

BRIEF DESCRIPTION OF THE DRAWINGS In the following more detailed description of a lock and key system according to the present invention reference will be made to the accompanying drawings in which;- Figure 1 is a perspective illustration of a conventional lock cylinder adapted 10 in accordance with the present invention and a construction key for operating the adapted lock cylinder, and Figure 2 is a comparison of a key for use in the lock and key system according to the present invention compared with a typical known 15 construction key, the known construction key being illustrated with the same key profile for the purposes of comparison.

DETAILED DESCRIPTION The Applicant has found that the security of construction keying can be improved by adapting an existing lock construction by the addition of a removable spacer, cap or spacer element to the external end of the lock cylinder. Alternatively a lock cylinder employing the inventive concept could be specifically constructed to include a removable spacer, cap or spacer element. For the purposes of convenience the 25 generic term "spacer element" will generally hereinafter be used.

Accordingly in one embodiment, as shown in Figure 1, there is illustrated part of a Euro cylinder lock 10 of known construction. This consists of a cylinder body 11 within which is located a pin cylinder 12, or plug as it is often called. According to 30 the present invention a spacer element 14 is removably applied to the extended face of the plug 1 2. It is applied in a manner that permits the plug 1 2 to be rotated by a key inserted therein.

This spacer element 14 includes an open ended slot 1 3 which is of a width sufficient 5 to enable a key K to be inserted therethrough and into the key slot of the plug 12. The length of the slot 1 3 is also sufficient to span the full length of the key slot in the plug 12. The slot is furthermore located in the spacer element 14 such that when the spacer element is in position on plug 12 the slot aligns with the key slot in the plug 1 2.

The spacer element 14 is fixed in a convenient manner to the face of the plug 12. The spacer element therefore effectively moves the datum stop for the top shoulder of the key. As a consequence the position of the top shoulder of a construction key differs from a normal key by the thickness (or front to back dimension "D") of the 15 spacer element 14. In this way the construction key K when inserted into the plug 12 ends up in the plug in a position where the construction key cuts correctly align with the cylinder pins as normal.

By way of example Figure 2 illustrates a typical construction key K with a key of the 20 same profile but notched in accordance with the present invention. Thus the shoulder S of key K is offset from the shoulder S' of a conventional construction key K'. The distance between shoulders S and S' is equivalent to the thickness D (or front to back dimension) of the spacer element 1 4.

The cuts on any key that does not have the notched top shoulder S will not align with the cylinder pins regardless of the key's code. Because conventional key cutting and duplication equipment reference from the top shoulder of a key simple duplication of a legitimately cut construction key or servant key will fail to provide a key which is capable of operating a lock which has the spacer element 14 in place on the plug 1 2. 6 The spacer elements 14 on the lock cylinders in a building can thus be removed by a builder prior to servant keys being used in the cylinders. As this removal of the spacer element 14 is an intentional action it provides a tamper evident step that cannot be reversed. In the alternative the building owner upon taking possession of the building can remove the spacer elements and use the servant keys to thereby deactivate the construction key code from the cylinders.

The present invention thus provides a simple yet effective means of eliminating the chance of construction keyed cylinders being accidentally operated by duplicates of existing keys in the market. It also eliminates the chance of a builder prematurely using servant keys, in this regard it is envisaged that the servant keys would be provided in a sealed hand-over kit thereby providing a means of dissuading builders from breaking the seal of the hand-over kit and using the servant key prior to hand over of the building to the building owner.

The spacer element 14 can be fitted to the plug 1 2 by convenient means. In a simple form of the invention the spacer element 14 is in the form of a cap that can be adhered to the plug 12 by an adhesive which prevents the cap from readily being removed from the plug during normal usage of the lock. However, with sufficient force or possible a specially designed lever the cap 14 can be removed. In a preferred form of the invention the cap 14 once removed cannot be applied once again to the plug 1 2.

It will be apparent to those skilled in the art that other means of fixing the cap or other form of spaced element to the plug can be used. For example a press fit type arrangement may be possible. Also it is within the scope of the invention that the plug be manufactured with a spacer element which was removable. For example a weakened area or tabs could be used to hold the spacer element in place yet allow removal to occur.

While the present invention has been illustrated by the description of the embodiments thereof, and while the embodiments have been described in detail, it is not the intention of the Applicant to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily 5 appear to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details, representative apparatus and methods, and illustrative examples shown and described. Accordingly, departures may be made from such details without departure from the spirit or scope of the Applicant's general inventive concept. 8

Claims (17)

WHAT IS CLAIMED IS:

1. A lock and key system including a spacer element detachably coupled to a plug of a lock, the spacer element having an aperture aligned with a key slot in the plug, and 5 a key having a datum surface which enables the lock to be operated by the key when the spacer element is coupled to the plug but not when the spacer element has been detached therefrom.

2. A lock and key system as claimed in claim 1 wherein the key is a construction key, 10 the system further including a servant key having a datum surface which enables the lock to be operated by the servant key when the spacer element has been detached from the plug.

3. A lock and key system as claimed in claim 2 wherein the construction key cannot 15 operate the lock after the servant key has been used to operate the lock.

4. A lock and key system as claimed in any preceding claim, wherein the spacer element is coupled to the plug by an adhesive which cannot be used to reattach the spacer element once it has been detached from the plug.

5. A key-operable lock including a plug with a key slot to receive a key for operation of the lock, and a spacer element detachably coupled to the plug, said spacer element having an aperture aligned with the key slot to enable a first key to be inserted into the plug to effect operation of the lock.

6. A key-operable lock as claimed in claim IS wherein the spacer element has a predetermined thickness so as to cooperate with a datum surface of a first key to 20 25 enable lock operation.

7. A key-operable lock as claimed in claim 6 configured for operation by a second key after the spacer element has been detached from the plug.

8. A key-operable lock as claimed in claim 7 configured to prevent operation of the 5 lock by a first key after the second key has been used to operate the lock.

9. A key-operable lock as claimed in any one of claims 5 to 8 wherein the spacer element is coupled to the plug by an adhesive which cannot be used to reattach the spacer element once it has been detached from the plug.

10. A spacer element configured for detachable coupling to a plug of a key-operable lock and having an aperture which, in use, aligns with a key slot in such a lock so as to allow a key to be inserted into the lock, the spacer element having a predetermined thickness so as to cooperate with a datum surface of a key to enable 15 lock operation.

11. A spacer element as claimed in claim 10, including an adhesive layer for coupling the spacer element to a plug of a key-operable lock, wherein the adhesive cannot be used to reattach the spacer element once it has been detached from the plug.

12. A lock and key system as claimed in claim 1, substantially as herein described.

1 3. A key-operable lock as claimed in claim 5, substantially as herein described. 25

14. A spacer element as claimed in claim 10, substantially as herein described.

15. A lock and key system substantially as herein described with reference to the accompanying drawings. 10 20 10

16. A key-operable lock substantially as herein described with reference to Figure 1 of the accompanying drawings.

17. A spacer element substantially as herein described with reference to Figure 1 of the accompanying drawings. ASSA ABLOY NEW ZEALAND LIMITED By its attorney DON HOPKINS & ASSOCIATES # 1 9 DEC ZUU8