AU2005202969A1 - A Lock with In Situ Hand Selection - Google Patents

Description

0 A LOCK WITH IN SITU HAND SELECTION ci 3 Field of the Invention This invention is directed to a lock and is particularly directed to a osimple mechanism by which a mortise lock can be converted from a "left-hand" lock to a "right hand" lock, and in particular to a lock where this can be achieved without disassembly of the lock components.

0Background Art 0 There are many types of locks that need to be "handed". Handing of a olock is particularly required in respect of a lock which is provided with an internal 10 handle and an external handle. With these types of locks, it is often desirable to have one handle locked and therefore unable to retract the lock tongue, while the other handle is able to retract the lock tongue. As an example, a screen door lock may be provided with a selectable hand emergency function to enable the screen door to be opened from the inside even if the screen door is locked from the outside.

The reason why these locks need to be handed is that the installer does not often know in advance which of the handles is to be the "working" handle.

With older lock designs, it was necessary to open up the lock and to rearrange the internal components to change the hand of the lock. Clearly, this was an unsatisfactory way to deal with the handing of a lock.

For this reason, there are many locks in the marketplace which can now be handed without substantial disassembly of the lock body.

One example is given in Australian patent 647236. This particular lock had two hubs (these being the internal components that engage with and retract the lock tongue). Inside the lock body is a carrier means which could be moved towards and away from the hubs. The carrier means supported a pair of catches which could engage with the hubs to prevent the hubs from rotating (thereby locking the tongue).

The carrier means was spring biased and was held in place by a screw. The screw was inside the lock body, but the lock body was provided with an opening to enable a screwdriver to engage with and manipulate the screw. This particular lock is an example of the known concept that has an internal mechanism that needs to be operated by a screw or similar device. A disadvantage with these internal mechanisms is their complexity (which increases the manufacture and assembly costs), and the difficulty in providing this type of mechanism within small lock bodies where there is o not much room.

Another arrangement is described in our earlier patent application PCT/AU95/00376. This lock assembly provided a locking head on a detent which is O slidingly adjustable to select the handle of the door which becomes the "working" or "active" handle. Again, adjustment of the locking head is achieved by loosening a screw or rotating a cam.

A third arrangement is described in Australian patent 717917. In this 0assembly, a lock handing member is positioned inside the lock body, and this can be Orotated using an external screwdriver to change the hand of the lock.

The arrangement in our earlier patent application and in Australian patent 717917 was still quite complicated and required quite a large number of machined parts that needed to be assembled into the lock body. Again, this made the arrangement difficult for use in a small lock body.

Therefore, there would be an advantage if it were possible to provide a lock that could be handed without opening up the lock body and rearranging the components within the lock body but which also did not require rotation of a screw/cam etc and therefore which did not require the relatively complicated componentry in the lock body to enable the lock to be handed using a screw/cam etc.

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 can be handed in a simple manner and which may overcome at least some of the above-mentioned disadvantages or which may provide a useful or commercial choice in the marketplace.

In a broad form, the invention resides in a lock having a lock tongue and having a first hub and a second hub, each hub able to cause retraction of a lock tongue, and means at least partially within the lock, the means preventing operation of the first hub and/or the second hub, the means able to be manipulated, preferably externally, of the lock to cause the means to selectively prevent operation of the first hub and/or the second hub.

In a more particular form, the invention resides in a lock, the lock 3 0 o comprising a lock body, a lock tongue which is movable between an extended position and a retracted position, a first hub which is rotatable to cause retraction of the lock, a second hub which is rotatable to cause retraction of the lock, and selective ohub locking means which prevents the first hub and/or the second hub from retracting the lock tongue, the selective hub locking means comprising an elongate locking bar which is movable between an engaging position where the elongate locking bar engages with the first hub and/or the second hub, and a retracted position where the 0 elongate bar does not engage with the first hub and/or the second hub, the elongate olocking bar being further rotatable about its longitudinal axis, the elongate locking bar being provided with a nose portion which has a special configuration such that upon rotation of the elongate bar about its longitudinal axis, the nose portion can engage with the first hub to prevent the first hub from retracting the lock tongue while enabling the second hub to retract the lock tongue, or the nose portion can engage with the second hub to prevent the second hub from retracting the lock tongue while enabling the first hub to retract the lock tongue.

In this manner, the elongate locking bar can be rotated about its longitudinal axis (typically by 180) to select which hub will be able to retract the lock tongue (the free hub) and which hub will be prevented from retracting the lock tongue (the locked hub). Thus, the "hand" of the lock can be selected without disassembling the lock components and can be done simply by rotating the locking bar.

Suitably, the locking bar can also be rotated to a position where it locks the first hub and the second hub. Thus, in a preferred embodiment, the locking bar can be rotated to preferentially lock either the first hub (and not the second hub), or the second hub (and not the first hub), and the locking bar can also be moved to a retracted position where both the first hub and the second hub are free to move.

The lock will typically comprise a mortise lock for use in a sliding or hinged door.

The lock body may be of any suitable size and may be formed of any suitable material. No particular limitation should be placed on the invention by any particular size and manufacture of the lock body.

The lock contains a lock tongue. If desired, the lock may contain a plurality of lock tongues. For instance, the lock may comprise a main lock tongue and an auxiliary lock tongue. The lock tongue may be of the type suitable for a hinged t3 4

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0 door and therefore the lock tongue may be provided with a bevelled nose portion on 3one side or both sides of the lock tongue. The lock tongue may be of any convenient size and may be made of any convenient material including steel. The lock tongue omay be provided with serrations/teeth and the like to provide an "anti-jemmying" effect to the lock tongue. The lock tongue may comprise a reciprocating lock tongue.

IHowever, the lock may also comprise a rotating lock tongue such as a hook bolt. A plurality of book bolts may be provided and these may be oppositely rotating hook 0bolts if desired. It is however preferred that the mechanism is used in relation to a omortise lock with a sliding lock tongue. The lock tongue may slide between an extended position where it projects from the lock body and can engage with a striker/keeper, and a retracted position where the lock tongue may be partially or fully retracted into the lock body. It is conventional for the lock tongue to be biased to the extended position by means of a spring or other type of biasing means which will typically be located within the lock body.

The lock contains a first hub and a second hub. The first hub and the second hub may be substantially identical in configuration. It is preferred that the first hub and the second hub are placed one on top of the other. A washer etc may be positioned between the first hub and the second hub. Each hub may comprise a central main body portion and an extending nose portion. The central main body portion will typically be provided with an opening to accommodate a spindle to enable each hub to be rotated. Each hub may be substantially flat and plate like in configuration. Suitably, a biasing means is provided to bias each hub into a naturally retracted position where it does not retract the lock tongue. The biasing means may comprise a spring.

The extending nose portion is typically adapted for operative engagement with the lock tongue to cause retraction of the lock tongue. Typically, the lock tongue will be supported by a frame member also known as a bolt frame). The frame member will typically be slidable within the lock body between a retracted position and an extended position. Suitably, the nose portion on the first hub and the second hub will engage with part of the frame member to retract the frame member and therefore the lock tongue. However, no particular limitation should be placed on the invention merely by the means by which the lock tongue is retracted into the lock body and by the means by which the hub causes retraction of the lock tongue.

0 o The lock contains a selective hub locking means. This component can function to selectively lock one of the hubs or optionally both of the hubs and even none of the hubs. The term "selectively lock" is meant to include that the component o can function to prevent at least one of the hubs from operating to retract the lock tongue.

0In a particular embodiment of the invention, the selective hub locking means can comprise an elongate member such as an elongate locking bar. The locking bar is typically movable between an engaging position where the locking bar ocan function to selectively lock at least one of the hubs, and a non engaging position.

It is preferred that the locking bar can slidably move between the engaging position and the non engaging position. However, it is also envisaged that the locking bar can rotate or otherwise move between the engaging position and the non engaging position.

The locking bar typically comprises an elongate member. The elongate member can have a length which depends on the size of the lock but will typically have a length of between 2-20 centimetres, and preferably between 5-10 centimetres.

The locking bar may be solid or hollow. The locking bar is able to rotate about its longitudinal axis, but apart from this the term "bar" should not be unnecessarily limited to any particular configuration. No particular limitation should be placed on the invention by the length of the elongate member. The elongate member can be formed from any suitable material including metal such as steel or die cast metal etc.

The locking bar contains a nose portion having a particular configuration. The term "nose portion" is meant to include (but not be limited to) one end region of the locking bar. The nose portion preferably comprises a stepped configuration which includes a front part having a reduced thickness or height relative to the remainder of the nose portion. Typically, the front part has a thickness of approximately 0.25-0.75 relative to the remainder of the nose portion and preferably the front part will be about half as thick of the remainder of the nose portion. The front part may comprise a single portion although it is envisaged that the front part may also comprise a plurality of fingers etc and it is not envisaged that the invention should be limited to the precise configuration of the front part as illustrated in the drawings.

The selective hub locking means is rotatable about its longitudinal axis.

6 o It is preferred that this member can rotate by 3600 by which is meant that the member 3 is not limited to only a partial rotation. However, the invention should not be limited only to a member that can rotate by 360' although it is considered expedient if the o member can do so. Thus, the selective hub locking means may be mounted or otherwise supported for rotation within the lock. Any type of means by which this can Va be achieved is considered to fall within the amrbit of the present invention.

It is however preferred that the selective hub locking means can be held 0 at a particular rotation angle. For instance, it is preferred that the selective hub o locking means can be held at a plurality of particular rotation angles. These angles may vary, however in an embodiment of the invention, the angles may be about 900.

If the angles are about 9Q0', the selective hub locking means can be held at 00, 1800, 2700, and back to Of course, the invention is not to be limited only to these particular angles, and it is envisaged that angles other than 90 can be used and that the selective hub locking means can be held at any number of particular rotation angles.

The selective hub locking means may comprise a special configuration to enable it to be held at a, or various, rotation angles. In one form, the locking means may be provided with a rectangular outer periphery which defines four faces substantially at right angles to each other. Rotation of the locking means by 90' will cause the locking means to move from one face to another face, and the faces will hold the locking means in the particular rotational orientation. It can be seen that if the locking means is provided with a triangular outer periphery, this will define three faces which can be substantially at 120' relative to each other. Alternatively, other outer periphery configurations are envisaged. The rectangular outer periphery preferably extends partially along the locking means, or comprises a number of spaced apart members which are rectangular.

It is preferred that the locking means can be manipulated externally of the lock body, when in the unlocking position. Thus, the lock body may be provided with an opening through which the locking means can be manipulated. Typically (but without limitation), one end of the locking means can be accessed through an opening in the lock body and this end of the locking means may be provided with a tool slot to enable a tool to be inserted into the slot to rotate the locking means. Alternatively, the locking means can be manipulated by a knob or other type of member that can be tt) 7

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Saccessed externally of the lock. Alternatively, the locking means can be manipulated by opening part of the lock body to rotate the locking means (typically however without any disassembly or replacement of components). It is however preferred that othe locking means can be manipulated without opening any part of the lock body.

The locking means may be biased into a naturally extending or a naturally retracting position where it can engage with or disengage with the hubs.

Any suitable form of biasing means can be used including a spring and the like.

0Brief Description of the Drawings IAn embodiment of the invention will be described with reference to the 0 following illustrations in which:.

Figure 1. Illustrates a mortise lock containing various components according to an embodiment of the invention.

Figure 2. Illustrates an exploded view of the mortise lock of figure 1.

Detailed Description Referring to the drawings and initially to figure 2, there is illustrated an exploded view of the lock. Briefly, the lock includes a pair of side plates 10, 11, a front plate 12, a cover plate 13, a lock tongue 14, a frame 15 to which lock tongue 14 is attached, a nylon guide insert 16, a component 17 which supports the hubs and a locking bar (described later), a first hub (otherwise known as a top hub) 18, a second hub (otherwise known as a bottom hub) 19, a spacing washer 20 that sits between the first hub and the second hub, a hub spring 21 which functions to bias the hubs to the "free" position, a selective hub locking means in the form of an elongate locking bar 22, an internal snib 23, an internal snib holder 24, and a snib spring 25, and optionally a deadlocking plate 26.

Briefly, the ability of the lock to be handed is caused by the elongate locking bar 22 engaging with or not engaging with the first hub 18 and the second hub 19. This will be described in greater detail below.

Figure 1 illustrates the above components fitted into the lock. Figure 1 illustrates only one "position" of the locking bar but as described below, the locking bar can be rotated to different positions and also can be extended and retracted to selectively lock/unlock either the first hub 18 or the second hub 19.

Specifically, hubs 18, 19 comprise plate like members that sit on top of each other and washer 20 is spaced between the two hubs. Each hub contains a square O8 o opening to accommodate a spindle which can be of conventional design. An external handle (not illustrated) is attached to the spindle. Typically, there will be an external handle on each side of the lock which will therefore comprise an "outside" handle and oan "inside" handle. These handles are not illustrated and can be of any conventional design. Therefore, turning of either handle will cause rotation of the spindle and therefore operation of the first hub or the second hub.

The particular arrangement comprises a "split" spindle which means that the "outside" handle is attached to a small spindle that engages with one of the ohubs, and the "inside" handle is attached to a separate small spindle that engages with the other hub. It can be seen from the design of washer 20 that the spindles cannot extend entirely through both hubs (as the washer does not have an opening to accommodate this). Thus, rotation of the outside handle will cause rotation of one hub (but not the other hub) and rotation of the inside handle will cause rotation of the other hub. The hubs can rotate either clockwise or anticlockwise independently from each other.

The hubs are however biased by hub spring 21 into the "retracted" position where the hubs do not retract lock tongue 14. Rotation of the hubs in a clockwise direction will cause retraction of lock tongue 14, and this rotation will be against the bias of hub spring 21.

Each hub is provided with a "nose" portion 27. The nose portion 27 engages with a rear portion 28 of frame 15 when the particular hub is rotated. Figure I shows the second hub 19 in engagement with rear portion 28 of frame 15. Rotation of second hub 19 in a clockwise direction (as viewed from figure 1) will cause frame to be pulled inwardly (that is towards the rear of the lock). Frame 15 is connected to tongue 14 and therefore this action also causes retraction of tongue 14. Frame (and therefore lock tongue 14) is biased into the extended position (where the lock tongue projects from the lock) by a spring (not illustrated) but which has one end extending into aperture 29 in the back of lock tongue 14, and the other end attached to a small button 30 on component 17.

Rear portion 28 has a sufficient size such that both the first hub 18 or the second hub 19 can engage with rear portion 28 to retract lock tongue 14.

The other main component of the lock that allows the hand of the lock to be changed is the elongate locking bar 22. The elongate locking bar 22 has a Ic) 9 o forward nose portion 31 (see figure 2) and a rear portion 32. Rear portion 32 is provided with a tool slot (not illustrated) which is accessible through a small opening in side plates 10 (or 11) (not illustrated). A tool can be inserted into the tool slot and o rotated to cause locking bar 22 to be rotated about its longitudinal axis as will be in greater detail below.

The nose portion of the elongate locking bar has a particular configuration and in the particular embodiment, the nose portion is stepped and 0therefore has a front part 33 which is approximately half the thickness of the on remainder of the nose portion 3 1.

010 The elongate locking bar can be reciprocated between a forward hub engaging position and a retracted free position where the locking bar does not engage either of the hubs. The degree of reciprocating movement is not large (typically between 5-10 millimetres). The locking bar 22 can be moved between the forward position and the retracted position by rotation of internal snib 23. The internal snib 23 is rotatably supported by a snib holder 24 (best illustrated in figure Internal snib 23 contains a lobe 34. This lobe 34 engages with snib spring 25 and specifically lobe 34 sits within a small recess 35 on snib spring 25 (best illustrated in figure 2).

Rotation of internal snib 23 in the clockwise direction will cause snib spring 25 to be deformed which in turn will cause locking bar 22 to be pushed to the forward position.

Snib spring 25 naturally biases the internal snib 23 back to the "free" position where the locking bar 22 is pulled back to the retracted position. Put differently, locking bar 22 is biased into the retracted position and needs to be pushed against the direction of the *bias into the extended (hub engaging) position.

The elongate locking bar 22 contains three spaced apart square members 36. These square members 36 present four land portions to the periphery of the locking bar. Thus, the locking bar 22 can be rotated about its longitudinal axis by 1800, 2700 and 3600 and in these rotational positions, the elongate locking bar 22 can be restrained against ftirther free rotation by being supported by a particular land portion. Put differently, the elongate locking bar can "click" from one land portion to another land portion upon rotation of the elongate locking bar about its longitudinal axis (by insertion of a tool into the tool opening which is in rear portion 32).

Referring now to the nose portion 31 of the elongate locking bar 22, as the elongate locking bar is rotated by 90', the front part 33 of the nose portion will be 01 turned. It is this effect that enables selective locking of the first hub 18 and/or the 3 second hub 19.

Specifically, when the elongate locking bar is in the position illustrated o in figure 1 and figure 2 (this can be called the 0' position) and the elongate locking bar is pushed forwardly by rotation of snib 23, the front part 33 will move forwardly Vainto the space 36 (s ee figure When the front part is in the space, it will prevent the second hub 19 from retracting lock tongue 14 as the second hub 19 cannot be rotated 0 in the clockwise direction. However, because the front part 33 has a reduced o thickness, the first hub 18 can still be rotated in the clockwise direction as it will simply pass over the top of first part 33 and first part 33 will not contact first hub 18.

Thus, in this position, the handle that is attached to second hub 19 is locked while the handle that is attached to first hub 18 can still be operated.

Retraction of elongate locking bar 22 (the retracted position being illustrated in figure 1) will enable both hubs to be operated (that is both external handles are unlocked).

When the elongate locking bar is in the retracted position the elongate locking bar can be rotated about its longitudinal axis by 90" which will cause the forward part 33 to now extend "vertically". When the locking bar is moved to the extended position the forward part 33 prevents rotation of both the second hub 19 and the first hub 18. Put differently, both hubs now engage against the "vertical" forward part 33 and therefore cannot retract lock tongue 14. In this position, both external handles are locked and can be unlocked by an internal snib and/or an external key.

If the elongate locking bar is rotated by another 9O* (that is 1800 from the position illustrated in figure the front part 33 is now "upside down". In this orientation, the second hub 19 can now retract lock tongue as it will sweep underneath the front part 33 while the first hub 18 cannot be retracted as it will strike the upside down front part 33. In this arrangement, the external handle connected to the top hub is locked while the external handle connected to the bottom hub is "active". Of course, the locking bar can also achieve this by initially positioning the locking bar in the retracted position, then turning it to the "upside down" position and then extending it to lock first hub 18.

The locking bar can be counter rotated back to the initial position.

Therefor6, it can be seen that the locking bar 22, by a combination of for-ward and tt 11

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o rearward sliding movement together with rotation of the locking bar about its longitudinal axis can selectively lock or unlock the first hub and not the second hub, the second hub and not the first hub, both the first hub and the second hub, or neither ohubs. In practice, the hand of the lock can be decided by rotating the locking bar about 1800. Once the locking bar has been turned. It can then be extended and retracted by snib 23 to lock and unlock one of the hubs but not the other hub.

cA key barrel can be fitted to also cause extension and retraction of the 0locking bar.

oIn practice, an installer of the lock can insert a tool, which may comprise the cylinder retainer pin 40 into the rear of elongate locking bar 22 to select the hand of the lock.

An optional feature of the lock is the deadlocking plate 26. The deadlocking plate 26 is a separate component that sits generally within component 17 and has a U-shaped cutout that sits over elongate locking bar 22 and just behind nose portion 31. Consequently, when the locking bar 22 is moved forwardly into the locking position, the deadlocking plate 26 travels with it (and extends at right angles from the locking bar 22), and when the locking bar 22 is retracted into the unlocking position, the deadlocking plate travels with it (as it is attached to the locking bar).

When the locking bar 22 is in the retracted position (see figurel), the deadlocking plate 26 sits behind button 30. The frame 15 has a cutout portion that enables the frame to retract without striking button 30. As long as the deadlocking bar 22 is in the retracted position, the attached deadlocking plate 26 sits behind button 30 and the frame (and therefore lock tongue 14) can be retracted. However, when the locking bar 22 is moved to the forward position not illustrated), the attached deadlocking plate 26 is moved forwardly and now sits behind portion 28 of frame 15. In this position, the frame cannot be retracted (and therefore lock tongue 14 cannot be retracted) and therefore the deadlocking bar 22 ultimately deadlocks lock tongue 14.

Because of the U-shaped cutout portion in the deadlocking plate 26, the locking bar 22 can still be rotated about its longitudinal axis and this does not cause any rotation of the deadlocking plate 26.

Throughout the specification and the claims (if present), unless the 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 12

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o 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 O 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.

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Claims (19)

1. A lock comprising a lock body, a lock tongue which is movable obetween an extended position and a retracted position, a first hub which is rotatable to cause retraction of the lock tongue, a second hub which is rotatable to cause retraction Iof the lock tongue, and selective hub locking means which prevents the first hub and/or the second hub from retracting the lock tongue, the selective hub locking cmeans comprising an elongate locking bar which is movable between an engaging oposition where the elongate locking bar engages with the first hub and/or the second hub, and a retracted position where the elongate bar does not engage with the first hub and/or the second hub, the elongate locking bar being further rotatable about its longitudinal axis, the elongate locking bar being provided with a nose portion which has a special configuration such that upon rotation of the elongate bar about its longitudinal axis, the nose portion can engage with the first hub to prevent the first hub from retracting the lock tongue while enabling the second hub to retract the lock tongue, or the nose portion can engage with the second hub to prevent the second hub from retracting the lock tongue while enabling the first hub to retract the lock tongue.

2. The lock as claimed in claim 1, wherein the locking bar is rotatable to a position where it locks the first hub and the second hub.

3. The lock as claimed in claim 2, wherein the locking bar is rotatable to preferentially lock either the first hub (and not the second hub), or the second hub (and not the first hub), and the locking bar is movable to a retracted position where both the first hub and the second hub are free to move.

4. The lock as claimed in any one of the preceding claims wherein the lock comprises a mortise lock for use in a sliding or hinged door.

5. The lock as claimed in any one of the preceding claims containing a plurality of lock tongues.

The lock as claimed in any one of the preceding claims wherein the n 14 O o lock tongue is a sliding lock tongue or a rotating lock tongue.

7. The lock as claimed in any one of the preceding claims wherein the ofirst hub and the second hub are substantially identical in configuration.

8. The lock as claimed in any one of the preceding claims wherein the first hub and the second hub are placed one on top of the other.

9. The lock as claimed in claim 8, containing a spacer member such as a 0 10 washer which is positioned between the first hub and the second hub.

The lock as claimed in any one of the preceding claims, wherein each hub has a central main body portion and an extending nose portion, the central main body portion being provided with an opening to accommodate a spindle to enable each hub to be rotated.

11. The lock as claimed in any one of the preceding claims wherein each hub is substantially flat and plate like in configuration, and a biasing means is provided to bias each hub into a naturally retracted position where it does not retract 2 0 the lock tongue.

12. The lock as claimed in claim 10 or claim 11, wherein the extending nose portion is adapted for operative engagement with the lock tongue to cause retraction of the lock tongue.

13. The lock as claimed in any one of claims 10-12, wherein the lock tongue is supported by a frame member also known as a bolt frame), the frame member being slidable within the lock body between a retracted position and an extended position, the nose portion on the first hub and the second hub engaging with part of the frame member to retract the frame member and therefore the lock tongue.

14. The lock as claimed in any one of the preceding claims, wherein the selective hub locking means comprises an elongate member such as an elongate If O o locking bar, and which is movable between an engaging position where the locking bar functions to selectively lock at least one of the hubs, and a non engaging position.

The lock as claimed in claim 14, wherein the locking bar is slidable between the engaging position and the non engaging position.

16. The lock as claimed in claim 14 or claim 15, wherein the locking bar contains a nose portion having a stepped configuration which includes a front part ohaving a reduced thickness or height relative to the remainder of the nose portion.

17. The lock as claimed in claim 16, wherein the front part has a thickness of approximately 0.25-0.75 relative to the remainder of the nose portion.

18. The lock as claimed in any one of the preceding claims, wherein the selective hub locking means is rotatable about its longitudinal axis, and preferably by

3600.

19. The lock as claimed in claim 18, wherein the selective hub locking means is retainable at a particular rotation angle. The lock as claimed in claim 19, comprising land portions or flat portions to retain the selective hub locking means at a particular rotation angle. 21. The lock as claimed in claim 20, comprising a portion with a rectangular outer periphery to define four land portions or flat portions substantially at right angles to each other, to enable the selective hub locking means to be retainable at four rotation angles which are at 90' relative to each other. 22. The lock as claimed in any one of the preceding claims, wherein the locking means can be manipulated externally of the lock body. 23. The lock as claimed in claim 22, wherein the lock body is provided with an opening and a tool can be passed through the opening to rotate the locking Ic) 16 0 0, means. 24. The lock as claimed in any one of the preceding claims, wherein the O locking means is biased into a naturally extending or a naturally retracting position where it can engage with or disengage with the hubs. VO A lock having a lock tongue and having a first hub and a second hub, 0, each hub able to cause retraction of a lock tongue, and means at least partially within Othe lock, the means preventing operation of the first hub and/or the second hub, the 10 means able to be manipulated, preferably externally, of the lock to cause the means to selectively prevent operation of the first hub and/or the second hub. 26. A lock substantially as hereinbefore described with reference to the accompanying drawings. DATED this 7 h day of July 2005 Assa Abloy Australia Pty Limited By their Patent Attorneys CULLEN CO.