WO2005054610A1

WO2005054610A1 - Improved lock

Info

Publication number: WO2005054610A1
Application number: PCT/NZ2004/000302
Authority: WO
Inventors: Vincent Keiron King; Peter Mark Hill; Michael Raymond Percy
Original assignee: Ingersoll-Rand Architectural Hardware Limited
Priority date: 2003-12-03
Filing date: 2004-11-25
Publication date: 2005-06-16
Also published as: AU2008227060A1; AU2007101222A4; AU2007101222B4; AU2004295641B2; AU2004295641A1

Abstract

A lock assembly (1) of a kind having a locking bar (15) which has the role of preventing or allowing rotation of a latch bolt actuating means (21). There is provided a mechanical transmission between an electrically actuable drive means (5) which in a power on situation retracts a drive member and in a power off situation extends or allows, e.g. by a biasing means (6), the extension of the drive member, or vice versa. The mechanical transmission is one that allows, by a rearrangement thereof, in the subsequent event of a power-off condition, the lock assembly can be either, in a 'failsecure' condition with the locking bar (15) preventing actuation of the latch bolt, or in a 'failsafe' condition with the locking bar (15) allowing actuation of the latch bolt (17).

Description

IMPROVED LOCK FIELD OF THE INVENTION The present invention relates to locks. BACKGROUND The present invention relates to an improved lock and in particular but not solely to locks whose status (locked or unlocked) can be controlled electronically, and in the situation where power is lost to the electronic control the lock is predetermined to be either locked ("failsecure") or unlocked ("failsafe"). There are many forms of lock (including such electronically controlled locks) reliant upon an electrically actuated solenoid or other drive means in order to control the locking status of a locking bar or device of a lock assembly. One such electrical lock form is that of Lockwood patent NZ 244230, which is reliant upon a solenoid that includes a core member that withdraws upon electrical actuation against the compressive bias of a spring. Such a lock, in one orientation of the solenoid with respect to the locking bar or device, in a power off (or power failure) situation, the locking bar prevents rotation of the latch actuator thereby holding the lock in its closed condition (so called "failsecure"). With such a lock kind, however, it is necessary to reverse the whole solenoid assembly if change from a "failsafe" to a "failsecure" condition is desired. The setting of "failsafe" or "failsecure" is thus carried out at the factory. This involves opening of the housing with consequential risks to part loss or displacement and/or loss of warranty. Another lock is that disclosed in NZ 329164 of Lockwood which has a solenoid with single orientation which can be used for both "failsafe" and "failsecure". However in order to achieve the change from "failsafe" to "failsecure" the housing must be in part disassembled and substantial disassembly, new parts and reassembly is required to effect the change from "failsafe" to "failsecure". The present invention recognises an advantage to be derived from an assembly whereby a solenoid or any equivalent electrical drive can be used in either a "failsafe" or a "failsecure" condition whilst in the same orientation and/or location within the overall lock assembly i.e., which does not require disassembly of the lock assembly housing, but rather is externally selectable. With a view therefore to that end the present invention envisages (i.e. a status determining "failsafe" or "failsecure") mechanical arrangement between the solenoid (or its equivalent) and the locking bar/locking device which has the effect of limiting or preventing the actuation of the actuator of the door latch. It is therefore an object of the present invention to provide such a lock or which goes some way to addressing the shortcomings of the prior art, or one which at least provides the public with a useful choice. As an alternative object of the present invention, the present invention in at least some embodiments offers the prospect of alteration from a "failsafe" to a "failsecure" condition and/or vice versa without disassembly of the lock housing and/or rearrangement of the solenoid or the equivalent. BREIF SUMMARY OF THE INVENTION In a first aspect the present invention consists in a lock assembly of a kind having a locking bar or locking device (hereinafter "locking bar") which has the role of preventing or allowing rotation of the latch bolt actuating means, wherein there is provided a mechanical transmission between an electrically actuable drive means which in a power on situation retracts a drive member and in a power off situation extends or allows (e.g. by a bias) the extension of the drive member, (or vice versa), and wherein the mechanical transmission is one that allows (preferably without disassembly of the lock assembly housing) a rearrangement thereof whereby in the subsequent event of a power-off condition, the lock assembly can be either (i) in a "failsecure" condition with the locking bar prevent actuation of the latch bolt, or (ii) in a "failsafe" condition with the locking bar allowing actuation of the latch bolt. In a second aspect the present invention consists in, in or for a lock assembly, a sub-assembly which involves a locking bar (e.g. as herein before defined), a solenoid that requires power on to work against a bias, a drive plate or member (hereinafter "drive plate") carried on or by part of the solenoid and movable relative to another part of the solenoid, wherein the locking bar is actuable by the action of a pinion acting on a rack with which it meshes, the pinion being captive by and yet movable relative to either (a) the drive plate or (b) the locking bar [preferably (a)] at least within limits of movement, and wherein at least one pinion drive axis of the pinion with respect to the drive plate, if (a), or the locking bar, if (b), can be varied, thereby to render the status of the lock assembly either "failsafe" or "failsecure" in power off conditions. Optionally when pivoted from one pinion drive axis, the power off condition of the solenoid means the pinion has moved the rack and thus the locking bar to the "failsafe" condition or alternatively, when pivoted by the other of two pinion drive axes such power off condition has moved the rack and thus the locking bar to the "failsecure" condition. Preferably the means whereby there is one or other of the pinion drive points or axes is determined by the location of a pivot member. Preferably said pivot member is held by an aperture in said drive plate relative to another aperture in said pinion. Alternatively said pivot member is held by an aperture in said pinion, relative to another aperture in said drive plate. Preferably said drive plate and pinion are able to be held relative to each other temporarily by a stop member to allow removal of said pivot member from one pinion drive axis location to another, to effect the change from "failsafe" to failsecure, or vice versa. Preferably said stop member engages at least said drive plate and said pinion. Preferably said pivot member is relocatable without disassembly of the housing of the assembly. Preferably said pinion is captive by said drive plate and housing so as to be restricted against movement of its central axis away from the axis of movement or some axis parallel thereto of the solenoid and each of said pinion drive axes flanks either side of that axis. Preferably the pivot member to be in said selected pinion drive axis is a threadedly engagable member. In a third aspect the present invention consists in a method of altering a solenoid including lock assembly between a power off "failsafe" and a power off "failsecure" condition which involves, without disassembly of the lock assembly other than relocation of a pivot member accessible externally of the housing of a rack engaging pinion, the change of the lock assembly from "failsafe" to "failsecure". Preferably said method involves the temporary use of a stop member to engage the internals of said lock assembly and substantially prevent their movement to allow said relocation of said pivot member. In a fourth aspect the present invention consists in in situ, a door or similar where its lock assembly has been altered to be a "failsafe" or "failsecure" condition prior to its fitment without any solenoid relocation and/or any housing disassembly. In fifth aspect the present invention consists in a lock assembly comprising or including a housing, a latch bolt that projects from the housing but which can be withdrawn, at least in part, into the housing an actuating means for withdrawing the latch bolt, a locking mechanism having a locking bar having a rack, said locking bar being moveable between a locking and non-locking condition in the sense that in one (the locking condition) it prevents movement of the actuating means and thereby in turn withdrawal of the latch bolt and, in the other condition (the unlocking condition), allows such movement, a pinion, spur gear or the equivalent (whether skeletal or otherwise) (hereafter "pinion") meshing with the rack and capable of causing the movement of said locking bar by virtue of rotation thereof relative to the rack, a carrier (hereafter "drive plate") of the pinion, which is moveable under the action of a solenoid or other electrical drive means (hereafter "solenoid"), wherein one or other of said drive plate and said pinion has two pinion drive axes for engaging a pivot member with one said of pinion or drive plate respectively, said pinion drive axes being one to either side of the locus of movement of a constrained guide, trunnion or other constraint of the pinion whereby, depending on the pinion drive axis used by the pivot member (eg, a screw) providing either a "failsecure" or "failsafe" status of the lock assembly. Preferably arrangement as such that the drive plate which travels under the action of the solenoid defines a locus of travel to which or parallel to which an axis of rotation of the pinion, spur gear or the like is held captive (eg, by a trunnion guidably slidable relative thereto) and with the rotation of that gear being further controlled by one of the two pinion drive axes being defined between that carrier and the pinion, spur gear or the like reliant on a pivot member located in one pinion drive axis whereby, when there is one such additional axis on one side of the locus or the axis parallel thereto there is movement of the rack in one direction as the drive plate travels and wherein when in the other axis location, the opposite occurs. Preferably said drive plate and pinion are able to be held relative to each other temporarily by a stop member to allow removal of said pivot member from one pinion drive axis to another to effect the change from "failsafe" to "failsecure" or vice versa. Preferably said stop member engages at least said drive plate and said pinion. Preferably the pivot member to be in said selected pinion drive axis is a threadedly engagable member. In a sixth aspect the invention consists in locking mechanism for a lock assembly having an electrical drive means actuated electrically in a power on condition and actuated by a biasing means in a power off condition, a drive plate actuable by said electrical drive means to drive, a pinion gear, whether complete or partial, said pinion gear driven by selection of one of two off centre or partial, said pinion gear driven by selection of one of two off centre pinion drive axes by said drive plate, said pinion drive axes either side of the line of action of said drive plate, a rack engaging said pinion gear to drive, a locking bar to allow a latch bolt to be locked or unlocked, wherein the choice of one of said pinion drive axes allows said latch bolt to be selected as locked in the event of power off, and selection of the other axis allows said latch bolt to be unlocked in the event of power off. Preferably said electrical drive is a linear stroke solenoid. Preferably said pivot location is selected by a removable pivot member engaging said drive plate and pinion gear at said selected pivot location. Preferably said locking mechanism and said lock assembly are contained in a lock housing. Preferably said drive plate and pinion are able to be held relative to each other temporarily by a stop member to allow removal of said pivot member from pinion drive axis to another to effect the change from "failsafe" to "failsecure" or vice versa. Preferably said stop member engages at least said drive plate and said pinion. Preferably said pinion drive axis selection is achievable without disassembly of said lock housing. Preferably said removable pivot member is threadedly engagable with one or both of said drive plate and/or pinion gear. Preferably said pinion gear rotates on a spigot from said housing and is captive between said housing and said drive plate. Preferably said spigot engages said drive plate in a guide on said drive plate. In a seventh aspect the invention consists in a locking mechanism for a lock assembly wherein a driving means has a line of action over a pinion driving a rack, wherein selection of a single pinion drive axis from an axis option on either side of the line of action, actuates at least in part the pinion and hence rack in one direction, the directions being mutually opposite depending on the choice of pinion drive axis. Preferably said rack actuates a locking bar controlling the locking and unlocking ability of a latch bolt. Preferably said driving means is a linear stroke solenoid having a retracted position when power is applied and extended position urged by a biasing means when power is off. Preferably said locking mechanism resides in a lock housing. Preferably said drive plate and pinion are able to be held relative to each other temporarily by a stop member to allow removal of said pivot member from one pinion drive axis to another to effect the change from "failsafe" to "failsecure" or vice versa. Preferably said stop member engages at least said drive plate and said pinion. Preferably said pinion drive axis selection is achievable external of said housing without disassembly of said housing. Preferably the pivot member to be in said selected pinion drive axis is a threadedly engagable member. In a further aspect the present invention consists in a lock assembly as herein described with reference to any one of more of the accompanying drawings. In a further aspect still the present invention consists in a sub-assembly as herein described with reference to any one of more of the accompanying drawings. In yet another aspect the present invention consists in a method of altering a solenoid including lock assembly as herein described with reference to any one of more of the accompanying drawings. In yet another aspect still the present invention consists in a locking mechanism as herein described with reference to any one of more of the accompanying drawings. In still a further aspect the present invention consists in a lock with a sub assembly or locking mechanism as herein described.. In another aspect the present invention consists in a lock as herein described with reference to any one of more of the accompanying drawings. To those skilled in the art to which the invention relates, many changes in construction and widely differing embodiments and applications of the invention will suggest themselves without departing from the scope of the invention as defined in the appended claims. The disclosures and the descriptions herein are purely illustrative and are not intended to be in any sense limiting.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present invention will now be described with reference to the accompanying drawings whereby: Figure 1 shows a general lock housing and assembly inside elevation with the cover removed to reveal the internals. In the configuration shown the lock is in a failsecure configuration, and the power is on, Figure 2 is a close up of the solenoid and mechanism in "failsafe" mode with the power-on, Figure 3 is a similar view to that of Figure 1 with the lock being in the failsecure configuration however in this situation the power is off, Figure 4 is a similar view to that of Figures 1 and 3 except the lock is in a "failsafe" configuration and the power is on, Figure 5 is a similar side on view to that of Figures 2 and 4 prior to removal of the pivot member from the drive plate, to switch from failsafe to failsecure, and Figure 6 is a similar view to that of Figure 5 with the stop member installed in the drive plate to allow the pivot member to be installed into the failsecure position in the drive plate.

DETAILED DESCRIPTION OF THE INVENTION With reference to Figures 1 through 6 is shown an electronically operatable "failsafe" "failsecure" lock assembly and locking mechanism. The lock assembly 1 having a lock face 2 which is presented on the peripheral edge of the door to engage within an assembly in the door jamb and a lock assembly back 4, the lock assembly from the face to the back being recessed into the door periphery. The lock assembly consists of a lock housing

3 within which are housed the components of the lock assembly, namely a drive means 5 which in this case is an electrically activated solenoid which consists of a external coil and an internal core, which upon application of electrical power to the external coil drives the internal core up into the external coil. Upon removal of power, such as when selected or in the instance of a power failure, there is no attraction of the core into the external coil and under the action of a biasing means 6, in this case a coil spring, the core is urged out from the solenoid to extend there from. Carried or actuated by the core of the solenoid is a drive plate 7 which is guided by a spigot 10. The spigot extends, in this embodiment, from the housing but may equally be a separate attached member or similar to the housing, or may be attached to the housing cover or may be split, having part on the housing and part on the cover. The spigot remains stationary and the drive plate 7 runs on the spigot 10 via a guide way or trunnion 8 which is sufficiently long to allow full or desired travel of the drive plate. The drive plate has pivot apertures 22A and 22B. A pinion gear 11 which is pivoted about the spigot 10 has a toothed region 24 for engaging with a complimentary toothed region on the rack 14. The pinion gear 11 also has apertures 26. A pivot member 12 (in Figure 2 located at 22a) is passed through one of the drive plates apertures into a mating pinion gear aperture at the pinion drive axis and fixed there. In the preferred embodiment the pivot member has a threaded portion which engages in a complimentary threaded portion on the drive plate 7. The pinion gear apertures 26A and B are distended longitudinally. The vertical (in this example) motion of the drive plate 7 causes the rotation of the pinion gear 11. The relative motion of rotation of the pinion gear 11 to the vertical motion of the drive plate 7 requires the pinion gear apertures 26A and B to be distended longitudinally. In Figure 1 the pivot member 12 is in the left hand of the two pivot locations. Thus when the power is applied to the solenoid 5 the internal core is drawn up into the external coil of the solenoid and due to the pivot member 12's location the pinion gear 11 is rotated clockwise thus raising the rack 14 and the locking bar 15 and locking piece (which allows for different handing of the lock) which is attached thereto. On the occurrence of power off or power failure the biasing means 6 extends the core from the external coil and thus the drive plate 7 moves vertically down to rotate the pinion gear 11 counter clockwise and thus move the rack 14 downwards and locking bar 15 downwards also. In this configuration the lock is said to be failsecure, that is in the event of a power off or power failure the locking bar is moved into a position to lock the door. In the preferred embodiment the rack 14 is part of the locking bar 15. The locking bar 15 in an unlocked position (as shown in Figure 1) is free of the rotation of rotatable latch actuating means 21. Such latch actuating means are common in the art and are often of a split hub variety whereby the means may be each rotated independently from either side of the lock assembly and door. A selectable handing mechanism known as a locking piece 25, also known in the art, exists on the locking bar. When the locking bar is in a locked position as shown in Figure 2 then depending on the rotational orientation of the locking piece, only one of the two split hub mechanisms may actuate the lock (e.g. a door handle internal may activate the lock but a door handle external may not or vice versa) or both members of the rotatable actuating means are prevented from rotation (e.g. in a fully locked door). The latch actuating means 21 acts upon the latch bolt 17 which has a latch head 19 which in a normal unactuated manner sits proud of the lock face 2 to engage a door jamb or similar to hold the door closed. Upon rotation (clockwise in Figure 1) of the latch actuating means 21 the latch bolt 17 is drawn back into the lock housing 3 to be free of the door jamb so that that door may be open or closed. The drive plate aperture 22B is slightly below that of the corresponding drive plate aperture 22A. This is to accommodate the correct throw length of the locking bar via the rack and pinion gear. Any position of the drive plate apertures which achieves the correct throw of the locking bar is considered to be within the scope of this invention. Figure 3 shows the failsecure configuration of Figure 1 when the power has been removed and thus under the biasing of the spring 6 the drive plate 7 is driven out and thus the pinion gear 11 is rotated anti-clockwise to draw the rack 14 and thus the locking bar 15 down to thus prevent the latch actuating means 21 from being able to activate the latch bolt 17. Figures 2, 4 and 5 show a "failsafe" configuration of the lock mechanism whereby the pivot member 12 is located in the 22 A drive plate aperture. Thus when power is applied the core and thus the drive plate 7 is drawn up and towards the solenoid and the pinion gear 11 is rotated anticlockwise to draw the rack 14 and thus the locking bar 15 down to prevent the rotation of the actuating means 21 thus preventing the withdrawal of the latch 17. In a situation where there is power off or a power failure as shown in

Figure 5 the solenoid core and drive plate are driven down under the influence of the biasing means 6 to thus rotate the pinion gear 11 clockwise which raises the rack 14 and locking bar 15 to thus free the latch actuating means 21 so that the latch may be drawn into the body of the lock housing. Control circuitry 27 and sensing means 28 (in the preferred embodiment as micro switches) are also present. The cover (not shown) for the lock housing and assembly produces an enclosed lock assembly externally accessible on which there are the pinion drive axes 13 A and B (which correspond with and are co-axial to drive plate apertures 22A and 22B) and thus the pivot member 12 can be removed from one pivot lock and moved across to another to turn the lock from a "failsafe" configuration to a "failsecure" configuration or vice versa. The lock as described can thus be changed from "failsafe" to "failsecure" simply by removal and replacement of pivot member 12. In the preferred method of removal the lock is laid upon its side. To change the lock from fail safe to fail-secure the pivot member 12 is unthreaded from the drive plate 7 and removed through the aperture in the lock closure. The stop member 29 (in the preferred embodiment is a wire clip) is then inserted into the lock closure slot (not shown) to retract the drive plate 7 so that the corresponding aperture 22B in the drive plate 7, pinion gear aperture 26A and aperture in the closure all align. The stop member 29 engages on the upper face of the lock housing to retain the drive plate in the desired position. The pivot member 12 can then be inserted via another lock closure aperture into the aligned apertures and threaded into the drive plate 7 and the stop member removed. The lock is now changed from fail safe to fail secure. To effect the change from fail secure to fail safe the above procedure is simply reversed. Whilst the preferred embodiment of the stop member 29 is a wire clip engaging the drive member, other alternatives are considered within the scope of the invention. For example the stop member 29 may be a simple piece of wire, or a screw driver, screw or other elongate item which is sufficiently slender and elongate to engage at least the drive plate. Alternatively it is not the drive plate that is engaged but rather the solenoid or any other singular or multiple parts of the moving chain such as the pinion gear (which may be accessed if provision is made) from the other side of the lock to achieve a similar object.

Claims

WHAT WE CLAIM IS:-

1. A lock assembly of a kind having a locking bar or locking device (hereinafter "locking bar") which has the role of preventing or allowing rotation of the latch bolt actuating means, wherein there is provided a mechanical transmission between an electrically actuable drive means which in a power on situation retracts a drive member and in a power off situation extends or allows (e.g. by a bias) the extension of the drive member, (or vice versa), and wherein the mechanical transmission is one that allows * a rearrangement thereof whereby in the subsequent event of a power-off condition, the lock assembly can be either (i) in a "failsecure" condition with the locking bar preventing actuation of the latch bolt, or (ii) in a "failsafe" condition with the locking bar allowing actuation of the latch bolt.

2. A lock assembly as claimed in claim 1 wherein said rearrangement is achieved without disassembly of the lock assembly housing)

3. A sub-assembly in or for a lock assembly which comprises or includes, a locking bar (e.g. as herein before defined), a solenoid that requires power on to work against a bias, a drive plate or member (hereinafter "drive plate") carried on or by part of the solenoid and movable relative to another part of the solenoid, wherein the locking bar is actuable by the action of a pinion acting on a rack with which it meshes, the pinion being captive by and yet movable relative to either (a) the drive plate or (b) the locking bar * at least within limits of movement, and wherein at least one pinion drive axis of the pinion with respect to the drive plate, if (a), or the locking bar, if (b), can be varied, thereby to render the status of the lock assembly either "failsafe" or "failsecure" in power off conditions.

4. A sub assembly as claimed in claim 3 wherein said pinion is captive by said drive plate.

5. A sub-assembly of claim 3 or 4 wherein when pivoted from one pinion drive axis, the power off condition of the solenoid means the pinion has moved the rack and thus the locking bar to the "failsafe" condition or alternatively, when pivoted by the other of two pinion drive axes such power off condition has moved the rack and thus the locking bar to the "failsecure" condition.

6. A lock assembly as claimed in any one of claims 3 to 5 wherein one or other of the pinion drive points or axes is determined by the location of a pivot member.

7. A lock assembly as claimed in claim 6 wherein said pivot member is held by an aperture in said drive plate relative to another aperture in said pinion.

8. A lock assembly as claimed in claim 6 wherein said pivot member is held by an aperture in said pinion, relative to another aperture in said drive plate.

9. A lock assembly as claimed in any one of claims 6 to 8 wherein said drive plate and pinion are able to be held relative to each other temporarily by a stop member to allow removal of said pivot member from one pinion drive axis location to another, to effect the change from "failsafe" to failsecure, or vice versa.

10. A lock assembly as claimed in claim 9 wherein said stop member engages at least said drive plate and said pinion.

11. A lock assembly as claimed in any one of claims 6 to 10 wherein said pivot member is relocatable without disassembly of the housing of the assembly.

12. A lock assembly as claimed in any one of claims 3 to 11 wherein said pinion is captive by said drive plate and housing so as to be restricted against movement of its central axis away from the axis of movement or some axis parallel thereto of the solenoid and each of said pinion drive axes flanks either side of that axis.

13. A lock assembly as claimed in any one claims 6 to 12 wherein the pivot member to be in said selected pinion drive axis is a threadedly engagable member.

14. A method of altering a solenoid including lock assembly between a power off "failsafe" and a power off "failsecure" condition which involves, without disassembly of the lock assembly other than relocation of a pivot member accessible externally of the housing of a rack engaging pinion, the change of the lock assembly from "failsafe" to "failsecure".

15. A method as claimed in claim 14 wherein said method involves the temporary use of a stop member to engage the internals of said lock assembly and substantially prevent their movement to allow said relocation of said pivot member.

16. In situ, a door or similar where its lock assembly has been altered to be a "failsafe" or "failsecure" condition prior to its fitment without any solenoid relocation and/or any housing disassembly.

17. A lock assembly comprising or including a housing, a latch bolt that projects from the housing but which can be withdrawn, at least in part, into the housing an actuating means for withdrawing the latch bolt, a locking mechanism having a locking bar having a rack, said locking bar being moveable between a locking and non-locking condition in the sense that in one (the locking condition) it prevents movement of the actuating means and thereby in turn withdrawal of the latch bolt and, in the other condition (the unlocking condition), allows such movement, a pinion, spur gear or the equivalent (whether skeletal or otherwise) (hereafter "pinion") meshing with the rack and capable of causing the movement of said locking bar by virtue of rotation thereof relative to the rack, a carrier (hereafter "drive plate") of the pinion, which is moveable under the action of a solenoid or other electrical drive means (hereafter "solenoid"), 5 wherein one or other of said drive plate and said pinion has two pinion drive axes for engaging a pivot member with one said of pinion or drive plate respectively, said pinion drive axes being one to either side of the locus of movement of a constrained guide, trunnion or other constraint of the pinion whereby, depending on the pinion drive axis used by the pivot member (eg, a 10 screw) providing either a "failsecure" or "failsafe" status of the lock assembly. 18. A lock assembly as claimed in claim 17 wherein said drive plate which travels under the action of the solenoid defines a locus of travel to which or parallel to which an axis of rotation of the pinion, spur gear or the like is held captive (eg, by a trunnion guidably slidable relative thereto) and with the

15 rotation of that gear being further controlled by one of the two pinion drive axes being defined between that carrier and the pinion, spur gear or the like reliant on a pivot member located in one pinion drive axis whereby, when there is one such additional axis on one side of the locus or the axis parallel thereto there is movement of the rack in one direction as the drive plate travels and wherein

20 when in the other axis location, the opposite occurs. 19. A lock assembly as claimed in claim 18 wherein said drive plate and pinion are able to be held relative to each other temporarily by a stop member to allow removal of said pivot member from one pinion drive axis to another to effect the change from "failsafe" to "failsecure" or vice versa.

25 20. A lock assembly as claimed in claim 19 wherein said stop member engages at least said drive plate and said pinion. 21. A lock assembly as claimed in any one of claims 18 to 20 wherein said pivot member to be in said selected pinion drive axis is a threadedly engagable member. 30 22. A locking mechanism for a lock assembly having an electrical drive means actuated electrically in a power on condition and actuated by a biasing means in a power off condition, a drive plate actuable by said electrical drive means to drive, a pinion gear, whether complete or partial, said pinion gear driven by 5 selection of one of two off centre or partial, said pinion gear driven by selection of one of two off centre pinion drive axes by said drive plate, said pinion drive axes either side of the line of action of said drive plate, a rack engaging said pinion gear to drive, a locking bar to allow a latch bolt to be locked or unlocked, 10 wherein the choice of one of said pinion drive axes allows said latch bolt to be selected as locked in the event of power off, and selection of the other axis allows said latch bolt to be unlocked in the event of power off. 23. A locking mechanism as claimed in claim 22 wherein said electrical drive is a linear stroke solenoid. 15 24. A locking mechanism as claimed in either claims 22 or 23 wherein said pivot location is selected by a removable pivot member engaging said drive plate and pinion gear at said selected pivot location. 25. A locking mechanism as claimed in any one of claims 22 to 24 wherein said locking mechanism and said lock assembly are contained in a lock housing. 20 26. A locking mechanism as claimed in any one of claims 22 to 25 wherein said drive plate and pinion are able to be held relative to each other temporarily by a stop member to allow removal of said pivot member from pinion drive axis to another to effect the change from "failsafe" to "failsecure" or vice versa. 27. A locking mechanism as claimed in claim 26 wherein said stop member 25 engages at least said drive plate and said pinion. 28. A locking mechanism as claimed in any one of claims 22 to 27 wherein said pinion drive axis selection is achievable without disassembly of said lock housing. 29. A locking mechanism as claimed in any one of claims 24 to 28 wherein 30 removable pivot member is threadedly engagable with one or both of said drive plate and/or pinion gear.

30. A locking mechanism as claimed in any one of claims 22 to 29 wherein said pinion gear rotates on a spigot from said housing and is captive between said housing and said drive plate. 31. A locking mechanism as claimed in claim 30 wherein said spigot 5 engages said drive plate in a guide on said drive plate. 32. A locking mechanism for a lock assembly wherein a driving means has a line of action over a pinion driving a rack, wherein selection of a single pinion drive axis from an axis option on either side of the line of action, actuates at least in part the pinion and hence rack in one direction, the directions being

10 mutually opposite depending on the choice of pinion drive axis. 33. A locking mechanism as claimed in claim 32 wherein said rack actuates a locking bar controlling the locking and unlocking ability of a latch bolt. 34. A locking mechanism as claimed in either of claims 32 or 33 wherein said driving means is a linear stroke solenoid having a retracted position when

15 power is applied and extended position urged by a biasing means when power is off. 35. A locking mechanism as claimed in any one of claims 32 to 34 wherein said locking mechanism resides in a lock housing. 36. A locking mechanism as claimed in any one of claims 32 to 35 wherein 20 said drive plate and pinion are able to be held relative to each other temporarily by a stop member to allow removal of a pivot member from one pinion drive axis to another to effect the change from "failsafe" to "failsecure" or vice versa. 37. A locking mechanism as claimed in claim 36 wherein said stop member engages at least said drive plate and said pinion.

25 38. A locking mechanism as claimed in any one of claims 32 to 37 wherein said pinion drive axis selection is achievable external of said housing without disassembly of said housing. 39. A locking mechanism as claimed in any one of claims 36 to 38 wherein the pivot member to be in said selected pinion drive axis is a threadedly

30 engagable member.

40. A lock assembly as herein described with reference to any one of more of the accompanying drawings.

41. A sub-assembly as herein described with reference to any one of more of the accompanying drawings. 42. A method of altering a solenoid including lock assembly as herein described with reference to any one of more of the accompanying drawings.

42. A locking mechanism as herein described with reference to any one of more of the accompanying drawings.

43. A lock with a sub assembly or locking mechanism as claimed in any one of claims 3 to 13 or 22 to 39.

44. A lock as herein described with reference to any one of more of the accompanying drawings.