Such locks have a bolt moveable between lock and unlock conditions.

The movement of the bolt from a lock to an unlock condition can, depending on the mechanism of the lock, be (in some cases) by one, both or neither handle when a locking mechanism is itself in a locked condition and by both when a locking mechanism is an unlocked condition.

Frequently locks of this kind have been provided in a form requiring some degree of dismantling and reassembly where the "handing" of the lock is to be changed from the condition in which it is supplied, ie; where it is set for (i) the left or right handle operation ("vestibule"), or (ii) neither handle operation when the locking mechanism is locked ("combination"). Most usually handing by a locksmith or carpenter is to choose in (i) whether a left or right handle, once installed, is to allow access despite the locking mechanism. For example, in a hotel room situation it is usual for the outside handle to be prevented from moving the bolt from a lock to unlock condition when the locking mechanism is locked but to allow, irrespective of the condition of the locking mechanism to allow the inside handle to move the bolt from the lock to unlocking condition.

Some locks with such capabilities are sometimes also arranged such that they can be reassembled into a condition that ensures that neither handle can move the bolt from the lock to unlock condition when the locking mechanism is in a lock condition.

Such an ability to alter the handedness of locks is to minimise the stock required to be held by retailers or carried by door lock installers and it frees carpenters from the worry at the time of purchase of what quantities of which handedness locks they require.

It also enables adjustments to be made to already fitted locks where requirements might change.

More recently there has been a trend to the provision of locks of a kind where the handling of the lock can be set by a simple adjustment of the assembly without any need for any substantial disassembly and reassembly.

One approach was that adopted in the EFCO 3000 Series mortise lock of EFCO Manufacturing Pty Limited of Australia. That particular lock series (which pre-dates those of Schlage and Lockwood hereinafter referred to) utilised a locking mechanism which included a resilient member which moved rectilinearly back and forth between its locked or unlocking condition but which captured a locking head between itself and the

casing or housing. The locking head could be moved transversely of said resilient member in a transverse direction normal to both the rectilinear back and forth direction (the rectilinear axis) and the axis of the bolt which itself was normal to said rectilinear axis. Such movement however could only occur against a movement of the resilient member away from the casing or housing.

Nevertheless the movement of the captured locking head enabled the locking head being presentable (when the locking mechanism is in a locked condition) to one of the actuators only at a time yet allowed movement to another condition which interferes with the operation ofthe other actuator, each actuator being under a direct or indirect rotational drive under the action of a handle.

The EFCO 3000 Series therefore included a locking mechanism having a locking head movable into a left or right handle actuator engaging condition by simply sliding movement transverse of the rectilinear axis of the movable member by which it is held captive. However some dis-assembly was required to allow the insertion of an addition locking head if for any reason an EFCO 3000 Series lock was to be taken to a condition where neither handle is to operate when the locking mechanism is locked.

Another example is that of Schlage (NZ) Limited disclosed in New Zealand Patent Specification No. 237000 (Australian Patent Specification No. 647236). In this particular embodiment a screw is either fitted into one side or the other of a selection means, ie. it is the screw alone that requires disassembly from the overall assembly and reassembly.

Depending on the "handedness" determined by the side of the mortise lock from which the screw is fitted a member carried by the locking mechanism rotates a pivoted assembly which on one side or the other carries a detent for the actuator. No screw means a condition (iii) as outlined above.

Another example is that of Lockwood Australia Pty Limited disclosed in PCT/AU95/00376 [W096/01355] which provides a locking head on a detent which is slidably adjustable during such a handing operation, such that subsequently a handle is either operative or inoperative for moving the bolt from the lock to unlock condition whilst the locking mechanism is in a locked condition.

Other examples of locks capable of being handed with minimal disassembly and reassembly or no disassembly or reassembly exist.

The present invention relates to still a further lock (hereafter "lock assembly") capable of being handed selectively to allow one or other of the handles to be associated therewith to be able to move the bolt from the lock to unlock condition when the locking mechanism is locked.

The present invention preferably also allows a locking mechanism detent of a kind used in our NT Legge 990 Series mortise lock to be modified to allow handing of the lock.

As used herein "handle" or "handles" should be construed in the broadest possible sense consistent with human actuation.

Accordingly in a first aspect the present invention consists in a lock assembly of a kind having a bolt moveable between a locking and unlocking condition relative to the housing of the assembly, there being at least one actuator (and preferably two actuators each) capable of moving the bolt from its locking to its unlocking condition (in use under the action of a handle(s) to be associated or associated therewith), and a locking mechanism moveable relative to said actuator(s) and said housing within said housing between an unlocked condition and a locked condition, said locked condition being such as to be capable in certain circumstances of allowing or preventing the movement of the or an actuator (such as in use is to occur by operation of a handle) and thus the movement of the bolt relative to the housing from a locking to an unlocking condition under the action of an actuator, wherein (where, as preferred, there are two actuators) said locking mechanism includes a member or assembly (hereafter "locking member") which has a captured (preferably protuberant) member capable of being rotated such that, in one condition and when said locking member is in its locked condition, will prevent (preferably with said protuberant member) the or an actuator from moving the bolt from a locking to an unlocking condition, and which, in another condition and when said locking member is in its locked condition, will prevent the other actuator from moving the bolt from the locking to unlocking condition.

Preferably said captured member is such that it can adopt at least a third condition which will prevent the use of either actuator to move the bolt from a locking to unlocking condition when the locking member is in its locked condition.

Preferably the bolt has a rectilinear movement axis and the rotation of the captured member is about an axis substantially parallel to that bolt axis.

Preferably said captured member is a turret member not capable of being rotated unless displaced axially against (with respect to the rotational axis) resilient and/or biasing means which holds the same locked in a previously set or preset condition.

Preferably said captured member under the action of a screwdriver or like tool from externally of the housing (or by use, externally of the housing, of an extension of said captured member) is capable of being displaced against said resilient and/or biasing means to allow rotational movement between said conditions.

Preferably the captured member includes a indexing means (eg; plurality of abutment faces) which will index said locking member unless displaced against said resilient and/or biasing means.

Preferably the capture member includes a protuberant member substantially as hereinafter described with reference to any one or more of the accompanying drawings.

Preferably the lock assembly has a locking mechanism operable substantially as hereinafter described with reference to one, some or all ofthe accompanying drawings or any mechanical equivalent thereof provided however there is a requirement for a measure of rotation of the captured member. In this respect the captured member can in some less preferred forms of the present invention be captured against the housing where such a locking member is itself resilient and is adapted to bear on part of said captured member.

Reference here in throughout to "against" in respect of "the resilient and/or biasing means" is not to be considered as restrictive on whether or not any such resilient means or biasing means acts upon the captured member on a side thereof remote from the direction from which handing is to be effected or not.

For example, while in a preferred form of the present invention the resilient member (which may or may not act as a bias on the captured member) is not deflected from a stable condition unless under a handing pressure (e.g. of a screwdriver) being passed through said captured member. Preferably such deflection causes the resilient member to act as a said biasing means for so long as the handing pressure remains. In that respect preferably it acts in the form of a leaf spring.

In other forms of the present invention a compression spring could similarly be held within the locking member against the captured member. Equally if desired, some member adapted to provide a bias in tension could be deployed from that side from which handing is to be effected.

The reference therefore to "resilient and/or biasing means" is to be interrupted in such a way as to provide a member which allows a rotation of the rotatable captured member only when it is urged to rotate (preferably from an indexed condition that prevents rotation). Such an ability to relocate the captured member at least largely within the locking member means that the captured member can have a loose fit within the locking member but not so loose as to allow non required rotation thereof about axes other than that desired and then only sufficiently loose once in its indexed condition to prevent rotation about the handing rotational axis unless unindexed by pressure.

In still a further aspect the present invention consists in a method of handing a lock which involves a method substantially as hereinafter described whether by reference to the specific embodiment hereinafter described or any form of lock as defined as being

in respect of the present invention.

One preferred form of the present invention will now be described with reference to the accompanying drawings in which; Figure 1A is a view in side elevation of a preferred mortise lock in accordance with the present invention having many of the elements of our earlier locks to which reference has been made (or which alternatively includes any of the other features except in respect of those disclosed in the aforementioned locks of EFCO, Schlage and Lockwood or for that matter any other manufacturer's mortise locks), Figure 1A showing the locking mechanism which under the action of a key or snib has the locking member with the captured member positioned so as to prevent the rotation of the actuator shown (the actuator capable of being rotated by the action of a handle (not shown) that would be shaft connected thereto in a known manner), such an actuator being able to withdraw the bolt from a locked condition, Figure 1B is a similar view to that of Figure 1A but showing the locking mechanism with its control of the locking member and the captured means positioned away from the actuator previously referred to in respect of Figure 1A, the preferably protuberant regions of the captured member not being able to prevent a handle actuated rotation of the actuator shown, Figure 2 is a rear elevation ofthe open housing of Figures 1A and 1B showing how the locking member is positioned with respect to the part of the housing actually depicted in Figures 1A, 1B and Figure 2, there preferably being access openings in the housing at the rear to allow a screw driver or the like to bear against a screw driver receiving slot or the equivalent in the captured member (preferably when in both the locked and unlocked conditions), Figure 3 is a side elevation view of a locking mechanism of the kind depicted in Figures 1A, 1B and 2 which is largely similar to that previously used by this company in its NT Legge 990 Series mortise locks but which includes provision (at that end to be positioned closest to the actuators) of means whereby captured means can be retained within the locking member yet have a protuberant region extend to be able to engage the actuator as shown in Figures 1A and 1B, Figure 4 is a side elevation view from the left of the locking member of Figure 3 showing a leaf spring and an indexing square all in a transparent view format, Figure 5 is the section "AA" of Figure 3, Figure 6 is the section "BB" of Figure 3, Figure 7 is a section as in Figure 5 but showing how a ball can be located therein (preferably with the assistance of a tapered channel if necessary) or being urged by a

spring (not shown) so as to provide, as shown in Figures 1A and 1B, a ball capable of holding the locking member in one of the two conditions as shown in Figures 1A and 1B by location in an indexing recess of the casing or housing so that a positive movement of the locking mechanism is required, eg; under the action of a key or a snib to effect movement between the conditions shown in Figures 1A and 1B, Figure 8 is an end elevation (as it would appear from the rear elevation of the housing) of the captured member in accordance with the present invention showing a screwdriver slot in a portion thereof and an indexing plateau (preferably of a rounded square form) leading to its preferably greater periphery which is cylindrical, Figure 9 is the opposite view to that of Figure 8 showing preferably the largely flat plateau of that region thereof providing the greatest periphery but showing an outstanding protuberant member which upon rotation could have the major axis of its rectangular form as shown (currently as horizontal) aligned vertically with respect to Figure 9 on either side or parallel with its current position as shown but differently positioned, preferably the arrangement being such that the vertical conditions referred to, lock one or other of the actuators against rotation ("vestibule") when the locking mechanism is locked, the condition as shown in Figure 9 if translated into a modified form of Figures 1 A and 1B would prevent locking of either actuator ("combination") and wherein the lower position referred to would allow simultaneous locking of both actuators, Figure 10 is a side elevational view of the captured members of Figures 8 and 9, Figure 11 is an elevational view of a resilient member capable by screwing or other means of being fixed as part of an assembly providing the locking member assembly of the locking mechanism, Figure 12 is a side elevational view of the leaf spring like member shown in Figure 11, and Figure 13 is an exploded isometric view of the locking member.

In the preferred form of the present invention the housing 1 includes a bolt 2 which protrudes from the housing or casing 1 when in its locked condition (see Figure 1A) and will preferably be substantially fully withdrawn into the housing in its unlocked condition (see Figure 1B).

In respect to the bolt 2 of course the reference to a "locked" or "unlocked" condition means that it will hold the door (or other hinged or otherwise supported structure) against opening. Locking in that respect does not mean that one or both of the handles is prevented from rotating and through the actuator of particular handle withdrawing the bolt in a known manner such as disclosed in the aforementioned prior art locks.

In the housing 1 it can be seen that an actuator 3 by rotation of the rectangular shaft 4 under the action of a handle (not shown) is capable of causing the withdrawal of the bolt 2. Essentially the projection 5 of the actuator 3 engages in an appropriate recess of the bolt 2 in a known manner and moves the bolt depending on the rotation of the actuator.

The snib or key receiving mechanism 6 maintains an engagement with the end region 7 of the locking member 8. The locking member 8 can best be seen in Figure 3.

It includes projections at the region 7 to engage with the key actuable regions of the locking mechanism and includes a passageway 9 into which the ball or other equivalent member 9A can locate (preferably under the action of a spring 9B) to engage in one of two recesses 10 ofthe casing 1.

The end ofthe locking mechanism 8 remote from the end region 7 is to capture and allow the rotation of the captured member 11 only against the resilience of a retaining leaf spring 12 which is bear on the face 13 ofthe captured member 11 (preferably undeflected) and to an extent that will not prevent the protuberant region 14 from assuming any of the three or four conditions referred to. Thus held in the captured member can be indexed in any condition (as desired) when received back into that recess 15 of the locking member 8 when the leaf spring 12 (which is located in the recess 12A) urges the member back to its indexed condition after an urging and rotation of the captured member 11 using the screwdriver slot or the equivalent 16. The pressure of a screwdriver 18 in the slot or the equivalent 16 is sufficient to remove the rectangular region 17 out of the indexing zone 15 (see Figure 6).

Persons skilled in the art will appreciate that with the preferred form of the present invention the condition of the captured member relative to the locking member in which it is included is unlikely to be affected by any slamming of a door into which the preferred mortise lock is fitted since the rotation requires pressure in a direction normal to forces likely to result from slamming. Moreover persons skilled in the art will appreciate that for the purpose of handing there will be no loose pieces and no opening of the housing (provided appropriate openings are provided in the rear face of the housing 1).

With a handed lock in accordance with the present invention the various handle options referred to herein throughout are available. Changing from one mode to another is easy upon the withdrawal in a known manner of such a mortise lock from its recess or prior to its ever being inserted in its recess.

Options abound but all such options offer alternatives to the prior art forms referred to hereinbefore and advantages over locks that requires any substantial or small amount of disassembly for handing purposes.