NZ760174A - A lock - Google Patents

Abstract

Disclosed herein is a lock.

Description

A LOCK Technical field The disclosure herein relates generally to locks, and specifically but not exclusively to a mortice lock.

Background A lock may be installed on a hinged barrier, examples of which include but are not limited to a door and a gate. The hinged barrier may be at a commercial or residential premises. It may be desired for a lock to have certain functions which may not be available or readily available. It may be desired to have a lock that may be configurable between multiple functions. It may be desired to have a lock that is resistant to inadvertent locking, which may result in lock out.

Summary A first aspect of the invention provides a lock comprising: a bolt mechanism comprising a rotationally mounted bolt and a rotary actuator operationally coupled to the rotationally mounted bolt, the rotary actuator being operable to rotationally withdraw the rotationally mounted bolt; and a cam mechanism independently operable of the bolt mechanism and a movably mounted interference member operationally arranged with the cam mechanism, the movably mounted interference member being movable, by operation of the cam mechanism, into interference with the bolt mechanism when the rotationally mounted bolt is at least one of: withdrawn, and so prevent the rotationally mounted bolt from being extended; and extended, and so prevent the rotationally mounted bolt from being withdrawn.

In an embodiment, the movably mounted interference member comprises a slidably mounted plate. The slidably mounted plate may comprise a finger. The slidably mounted plate may be slidable into interference with the bolt mechanism, such that the finger interferes with the bolt mechanism. The finger may be received in a cavity defined by the rotary actuator when the slidably mounted plate interferes with the bolt mechanism. The cavity may be inaccessible to the finger when the rotationally mounted bolt is one of withdrawn and extended.

In an embodiment, the cam mechanism may comprise a rotationally mounted cam and a cam follower attached to the interference member. The cam mechanism may comprise another cam follower. The cam and the cam follower may be cooperatively arranged to move the interference member into interference with the bolt mechanism. The cam and the other cam follower may be cooperatively arranged to move the interference member out of interference with the bolt mechanism. The cam may be configured to be operationally coupled to a cylinder lock. The cylinder lock may be on one side of the movable mounted interference member.

In an embodiment, the interference member may comprise yet another cam follower. The embodiment may comprise another cam configured to be operationally coupled to another cylinder lock on another side of the movably mounted interference member, the other cam and the yet other cam follower being cooperatively arranged to move the interference member out of interference with the bolt mechanism. The other cam and the rotary actuator may be cooperatively arranged for the other cam to operate the rotary actuator. The other cam may comprise a plurality of elongate radial projections and the rotary actuator may be configured to be engaged by the plurality of elongate radial projections for actuation thereby.

An embodiment comprises a pivotally mounted lever having an end adjacent the bolt mechanism and another end adjacent the movably mounted interference member. The other end is positioned for stopping the movably mounted interference member being moved into interference with the bolt mechanism when the other end is engaged with the bolt mechanism.

An embodiment comprises a pivotally mounted stop biased into a path of the movably mounted interference member and so stop movement of the movably mounted interference member into interference with the bolt mechanism. The cam mechanism and pivotally mounted stop may be cooperatively arranged such that the cam mechanism moves the pivotally mounted stop out of the path of the movably mounted interference member when the cam is operated.

An embodiment comprises a sliding member movable between a first position and a second position by operation of the rotary actuator. The sliding member may interfere with the cam mechanism in only one of the first position and the second position to prevent the movably mounted interference member being moved by the operation of the cam mechanism into interference with the bolt mechanism. The sliding member may be configurable in a first configuration wherein the sliding member interferes with the cam mechanism in the first position and a second configuration wherein the sliding member does not interfere with the cam mechanism. The sliding member may comprise two longitudinally displaced stop receivers whereby the sliding member has the first configuration when one of the two stop receivers receives a stop and the sliding member has the second configuration when the other of the two stop receivers receives the stop. The rotary actuator may comprise a plurality of gear teeth and the sliding member may comprise a rack operationally coupled to the plurality of gear teeth.

In an embodiment, the rotary actuator is configured to engage a torque transmitting bar for transmitting a torque from a handle.

In an embodiment, the rotary actuator comprises at least one gear tooth for engaging the movably mounted interference member. Operation of the rotary actuator may actuate the at least one gear tooth to move the moveably mounted interference member out of engagement with the bolt mechanism. The movably mounted interference member may comprise a pin for engagement with the at least one gear tooth.

In an embodiment, the lock comprises a mortice lock.

A second aspect of the invention provides a lock comprising: a bolt mechanism comprising a rotationally mounted bolt and a rotary actuator operationally coupled to the rotationally mounted bolt, the rotary actuator being operable to rotationally withdraw the rotationally mounted bolt; and a cam mechanism and a movably mounted interference member operationally arranged with the cam mechanism, the movably mounted interference member being movable, by operation of the cam mechanism, into interference with the rotary actuator and so immobilise the rotationally mounted bolt.

A third aspect of the invention provides a lock comprising: a bolt mechanism comprising a rotationally mounted bolt and a rotary actuator operationally coupled to the rotationally mounted bolt, the rotary actuator being operable to rotationally withdraw the rotationally mounted bolt; and a cam mechanism and a movably mounted interference member operationally arranged with the cam mechanism, the movably mounted interference member being movable, by operation of the cam mechanism, into interference with the bolt mechanism, wherein the rotationally mounted bolt is at least one of: withdrawn, and so prevent the rotationally mounted bolt from being extended; and extended, and so prevent the rotationally mounted bolt from being withdrawn.

A fourth aspect of the invention provides a method for operating a lock, the method comprising the steps of: operating a rotary actuator of the lock to rotationally withdraw a rotationally mounted bolt of the lock; and operating a cam mechanism to move a movably mounted interference member of the lock into interference with a bolt mechanism of the lock, the bolt mechanism comprising the rotationally mounted bolt, when the rotationally mounted bolt is at least one of: withdrawn, and so prevent the rotationally mounted bolt from being extended; and extended, and so prevent the rotationally mounted bolt from being withdrawn.

Any of the various features of each of the above disclosures, and of the various features of the embodiments described below, can be combined as suitable and desired.

Brief description of the figures Embodiments will now be described by way of example only with reference to the accompanying figures in which: Figures 1 shows a front elevational view of the internals of an embodiment of a lock with a lock bolt withdrawn.

Figures 2 shows a front elevational views of the internals of the lock of figure 1 with a lock bolt extended.

Figures 3 to 6 each comprise a cut away view detailing an interference member and a cam mechanism of the lock of figure 1.

Figure 7 shows a detail in a perspective view of a rotary actuator of the lock of figure 1.

Figures 8 – 9 show operation of the cam mechanism of figures 3 to 6.

Figures 10 – 15 show rear elevational views of the internals of the lock of figure 1.

Figures 16 and 17 show front elevational views of the internals of another embodiment of a lock.

Figures 18 and 19 each comprise a cut away view detailing an interference member of the lock of figures 16 and 17.

Figures 20 and 21 show parts common to the embodiments of figures 1 to 19, with some parts omitted for illustrative purposes.

Figure 22 is a perspective view corresponding to figure 20.

Figure 23 shows the unlocking of the lock of figure 1.

Figure 24 shows a cut away front elevation view of the lock embodiment of figures 16 to Figures 25 and 26 show front elevational views of the internals of yet another embodiment of a lock.

Figures 27 and 28 comprise rear cut away perspective views corresponding to figures 25 and 26.

Figures 29 and 30 show first and second configurations of a sliding member of the embodiment of figures 25 – 28.

Figure 31 shows an elevational view of the sliding member of the embodiment of figures 25-28.

Description of embodiments Figures 1 and 2 show front elevational views of the internals of an embodiment of a lock, the lock being generally indicated by the numeral 10. Also shown in figure 1 are orthogonal axes x,y,z, wherein the lock is aligned to the x, y, and z axes. The lock 10 comprises a bolt mechanism 12. The bolt mechanism 12 comprises a rotationally mounted bolt 14 and a rotary actuator 16 operationally coupled to the rotationally mounted bolt 14. The rotary actuator 16 is operable to rotationally withdraw and extend the rotationally mounted bolt 14. The lock 10 comprising a casing, a rear portion of the casing 68 being shown in figure 1. A front portion of the casing 68 is not shown. The rotationally mounted bolt 14 is within the housing when withdrawn. A distal end 15 of the rotationally mounted bolt 14 is external of the housing when extended. The rotationally mounted bolt 14 is shown withdrawn in figure 1 and extended in figure 2. The bolt 14 is rotated around a bolt pivot 13 in the form of a shaft mounted in casing 68 to move it between the withdrawn and extended positions. The lock 10 comprises a cam mechanism 18 and a movably mounted interference member 20 operationally arranged with the cam mechanism 18. The movably mounted interference member 20 is movable, by operation of the cam mechanism 18, into interference with the bolt mechanism 12 when the rotationally mounted bolt 14 is at least one of: • withdrawn, and so prevent the rotational mounted bolt 14 from being extended; and • extended, and so prevent the rotationally mounted bolt 14 from being withdrawn.

An optional circlip (not shown, but the same as circlip 213 of figure 27) is fixed to the bolt pivot 13 to hold the bolt 14 thereto. In the lock 10, the cam mechanism 18 is independently operable of the bolt mechanism 12. The cam mechanism 18 may be moved into interference with the rotary actuator and so immobilise the rotationally mounted bolt.

The lock 10 is in the form of a mortice lock. The lock 10 may be disposed in a mortice formed in an edge of a hinged barrier – examples of which include but are not limited to a gate and a door – a piece of furniture or generally any other structure as desired and suitable. Generally, but not necessarily, the mortice lock is disposed in the mortice with the z axis pointing upwards.

Fastener receiving apertures are formed in attachment lugs 17 for fastening the lock 10 to the hinged barrier. The centrally disposed rotary actuator 16 is configured to engage a torque transmitting bar in the form of a square cylinder parallel to pivot pin 13 for transmitting a torque from a handle and which is transversely orientated. The torque transmitting bar is in use simultaneously received in a square profiled aperture 11 defined by the rotary actuator 16 and another square socket defined by the handle. The torque transmitting bar may be engaged by handles on opposite sides (front and back) of the lock 10, for example. Alternatively, the torque transmitting bar may be engaged by only one handle on one side of the lock. The rotary actuator 16 comprises a journal 17 on opposite sides thereof, one of which is shown in figure 7. The lock casing 68 comprises plain bearings that receive the opposite journals 17.

The rotary actuator 16 has a radially displaced boss attached to the underside of a distal end of finger 21 that is received within a slot defined by the bolt 14, forming a linkage between the rotary actuator 16 and the bolt 14 for rotation of the bolt 14. Spring 19 keep the parts of the rotary actuator assembly 16 together.

The movably mounted interference member 20 comprises a slidably mounted plate 22 attached to a finger 24, which in this but not all embodiments is integral of the slidably mounted plate 22.

Figures 3 to 6 each comprise a cut away view detailing the interference member 20 and the cam mechanism 18. The movably mounted interference member 20 is movable between an interference position (figures 5 and 6) and a non-interference position (figures 3 and 4). Taken in sequence, figures 3 to 5 show how the operation of the cam mechanism 18 can slide the movably mounted (in this embodiment slidably mounted) interference member 20 into interference with the rotary actuator 16 of the bolt mechanism 12. This prevents rotation of the rotary actuator 16 around its pivot and hence its actuation by the handle. When the interference member 20 is in interference with the bolt mechanism 12, the finger 24 of the slidably mounted plate 22 interferes with the bolt mechanism 12. A tag 26 of the finger 24 is received in a cavity 28 defined by the rotary actuator 16 when the movably mounted interference member 20 interferes with the bolt mechanism 12. As shown in figures 3 and 4, the tag 26 is withdrawn from the cavity 28 when the movably mounted interference member 20 is in the non-interference position. The cam mechanism 18 comprises a rotationally mounted cam 30 and a cam follower 32 attached to the interference member 20. The cam 30 is configured to be operationally coupled to a cylinder lock to one side of the movably mounted interference member 20. The cam 30 comprises a cylinder lock engaging feature 36 in the form of a ridge extending outwardly from cam plate 34. The cylinder lock engaging feature rotationally locks with an end of the cylinder lock, which defines a slot for receiving the cylinder lock engaging feature 34. The position of the slot and ridge may be reversed. Figure 6 shows the cam 30 at a neutral position for removal of a key from a cylinder lock when coupled thereto. A user can insert a key into the cylinder lock operationally coupled to the cam 30 and rotate the key within the cylinder lock in a first rotational direction to actuate the cam 30 to rotate the cam through the positions shown in figures 3 to 5, placing movably mounted member 20 in the interference position and the lock in a locked condition. The user can then rotate the key within the cylinder lock in a second rotational direction counter to the first rotational direction to actuate the cam 30 and move the cylinder lock and com 30 to the neutral position shown in figure 6. The key may be removed when in the neutral position. The cylinder lock may be, for example, for operation from inside of a building, and may be used to unlock the lock from the inside of the building for egress from the building.

The lock may be installed, however, for the cylinder lock to be operated from outside of the building to enable ingress. Figure 7 shows a detail in a perspective view of the rotary actuator 16 and finger 24. The rotary actuator 16 comprises two parts 90,92, which are independently manufactured and subsequently joined, for manufacturing purposes.

In the embodiment of figures 1 – 15, but not all embodiments, the movably mounted interference member 20 interferes with the bolt mechanism 12 when the bolt 14 is extended. The cavity 28 is positioned for receiving the tag 26 when the bolt 14 is extended, having a cavity opening laterally orientated and with the tag 26 at the opening. The cavity 28 is inaccessible to the finger 24 when the rotationally mounted bolt 14 is withdrawn, the cavity opening being longitudinally orientated and with the tag 26 removed from the opening. The rotary actuator 16, including the cavity 28 rotates around a rotation axis thereof to extend or withdraw the bolt 14. When the bolt 14 is withdrawn, the cavity 28 is blocked to the finger 24 by a blocking member 36 of the rotary actuator 16 in the form of a collar, and so the tag 26 cannot be received within the cavity 28. In alternative embodiments, the blocking member 36 may take the form of a finger or generally any suitable form.

Taken in sequence, figures 8 and 9 show how the operation of the cam mechanism 18 can slide the movably mounted member out of interference with the bolt mechanism 12 and to a non interference position. The cam mechanism 18 comprises another cam follower 35. In this embodiment, the other cam follower 35 is attached to the interference member 20 and is integral thereto, however is not so in an alternative embodiment. The cam 30 and the cam follower 32 are cooperatively arranged to move the interference member 20 into interference with the bolt mechanism 12, and the cam 30 and the other cam follower 35 are cooperatively arranged to move the interference member 20 out of interference with the bolt mechanism 12.

Figures 10 – 12 show rear elevational views of the internals of the lock 10. The interference member 20 comprises yet another cam follower 38. The other can follower 38 is in the form of a tag turned out from the plane of the plate 22. The cam mechanism 18 comprises another cam 40, which is configured to be operationally coupled to another cylinder lock on another side of the movably mounted interference member 20. The other cam 40 comprises a cylinder lock engaging feature 42 in the form of a ridge extending outwardly from cam plate 44. The cylinder lock engaging feature 42 rotationally locks with an end of the other cylinder lock, which defines a slot for receiving the cylinder lock engaging feature 42. The position of the slot and ridge may be reversed. The other cylinder lock may be, for example for operation from outside of a building, for example, and may be used to unlock the lock 10 for entry into the building. The other cam 40 and the yet other cam follower 38 are cooperatively arranged to move the interference member 20 out of interference with the bolt mechanism 12. Taken in sequence, figures 10 to 12 show how operation of the other cam mechanism 40 can slide the movably mounted interference member 20 out of interference with the bolt mechanism 12 to the non interference position. In figure 10, the other cam 40 is shown in a neutral position for insertion of a key into the other cylinder lock or removal therefrom. In figure 11, the other cam 40 has been rotated into engagement with the other cam follower 38. In figure 12, the other cam 40 has been further rotated to move (in this embodiment push) the cam follower 38 away from cam 40 and move the interference member 20 out of engagement from the rotary actuator 16 of bolt mechanism 12.

Figures 13 – 15 show the same back elevational views of the internals of the lock 10 as figures shown in figures 10 – 12, however taken in sequence these figures show the lock 10 being operated for withdrawal of the rotationally mounted bolt 14. The other cam 40 and the rotary actuator 16 are cooperatively arranged for the other cam 40 to operate the rotary actuator 16. The other cam 40 comprises a plurality of elongate radial projections 43, and in this embodiment but not all embodiments is in the form of a rabbit cam. The rotary actuator 16 is configured to be engaged and operated by the other cam 40, having gear teeth 41 for engaging at least one of the elongate radial projections 43 of the other cam 40.

Rotationally mounted parts 14, 16,30 and 40 are rotatably mounted for rotation around parallel axis of rotation, which are each parallel to the x direction.

Figures 16 and 17 show front elevational views of the internals of another embodiment of a lock, with the lock being generally indicated by the numeral 100. Parts of the lock 100 similar and/or identical in form and/or function to parts of lock 10 are similarly numbered. Unlike for lock 10, the movably mounted interference member 20 of lock 100 can interfere with the bolt mechanism 12 when the bolt 14 is withdrawn. The movably mounted interference member 20 cannot interfere, however, with the bolt mechanism when the bolt is extended. As shown in figure 18, the rotary actuator 16 has, in this alternative embodiment, a cavity positioned for receiving the tag 26 when the bolt 14 is retracted instead of extended. The operations of locks 10 and 100 may be reversed simply by exchanging the rotary actuators 16. Lock 10 may be additionally supplied with the rotary actuator 16 of lock 100, so that a user can change rotary actuators 16 to change the function of the lock.

Figures 18 and 19 are cut away views detailing the interference member 20 of lock 100 and the cam mechanism 18. Taken in sequence, figures 18 and 19 show how the operation of the cam mechanism 18 can slide the slidably mounted plate 22 into interference with the rotary actuator 16 of the bolt mechanism 12. The lock 100 comprises a pivotally mounted lever 50, mounted on pivot 56 in the form of a boss, having an end 54 adjacent the bolt mechanism 12 and another end 52 adjacent the movably mounted interference member 20. The pivot 56 is intermediate ends 52,54. The rotary actuator 16 has a lever engaging surface 58 that is presented to the end 54 of the pivotally mounted lever 50 when the cavity 28 is arranged for receiving the tag 26. In figures 18 and 19, the interference member 20 can be moved by the cam mechanism 18 for the finger 26 to enter the cavity 28 and lock the bolt mechanism because the pivotally mounted lever 50 is free to rotate clockwise when urged by the interference member 20. Another lever engaging surface 61 is presented to the end 54 of the pivotally mounted lever 50 when the cavity 28 is blocked to the finger 24. The other lever engaging surface 61 extends radially outwardly further than the lever engaging surface 58, to limit inward movement of the end 54. Figure 24 shows the other lever engaging surface 61 engaging with the end 54 when the cavity 38 is blocked to the finger 24. When the cam 16 has the rotational orientation shown in figure 24, the other lever engaging surface 61 prevents end 52 of lever 50 from being moved from the position shown in figure 18 to the position shown in figure 19 by the interference member 20. Consequently, a user will be unable to turn a key in a lock cylinder operationally coupled to cam mechanism 18, providing feedback on the state of the lock 100 to the user.

Figures 20 and 21 show parts common to lock 10 and lock 100. The locks 10,100 comprise a pivotally mounted stop 60. The pivotally mounted stop 60 is pivotally mounted on a boss 64.

The locks 10,100 each comprise a biasing member 62 in the form a compression spring having an end 70 seated in biasing member seat 66 integrally formed in a lock casing 68. Generally any suitable resilient member may be used for the biasing member, for example a block of elastomeric material. Another end 72 of the spring 62 engages the pivotally mounted stop 60 at an outer surface thereof. The pivotably mounted stop 60 comprises a fork comprising a pivotably mounted arm 74 attached to a first distal prong 76 and a second distal prong 78. The other end 72 of the biasing member 62 engages the pivotably mounted stop 60 at the first distal prong 76 and biases the pivotally mounted stop 60 in a rotational direction, which is a left handed direction with respect of axis x. As seen in figure 21, the cam 18 slidingly engages the pivotally mounted stop 60 and is operable to move the pivotally mounted stop 60 in a counter rotational direction. In this but not necessarily in all embodiments the cam arm 81 slidingly engages the second distal prong 78, which follows cam 18.

The biasing member 62 biases the pivotally mounted stop 60 into a path of the movably mounted interference member 22. Figure 22 shows the pivotally mounted stop 60 biased into the path, and interfering with the movably mounted interference member 22, which stops the movably mounted interference 22 member being moved into interference with the bolt mechanism12.

First distal prong 76 comprises a turned out tag 79 that is shown abutting movably mounted interference member 22 in figure 22. This may prevent inadvertent locking of the bolt in one of the extended and withdrawn positions, for example by the hinged barrier being slammed shut.

As described above, the cam 81 can be operated to move the pivotally mounted stop 60 in a counter rotational direction, which moves the pivotably mounted stop 60 out of the path of the movable mounted interference member.

Figure 23 is another view of the lock of figure 1, and shows a gear tooth 80 of the rotatory actuator 16 engaging a pin 82 of the movably mounted interference member 20 to slide the movably mounted interference member 20 out of engagement. The rotary actuator 16 is, in this case, acting as a cam, and the pin 82 as a cam follower. Consequently, a person can operate a door handle to move the interference member 20 to the left – the non-interfering position – if the door is slammed causing the interference member 20 to move to the right and hit the pivotally mounted stop 60. If the gear tooth 80 did not push the interference member back, the lock may jam during operation.

Figures 25 and 26 show front elevational views of the internals of yet another embodiment of a lock, the lock being generally indicated by the numeral 200. Parts of the lock 200 similar and/or identical in form and/or function to parts of lock 10 are similarly numbered. The lock 200 comprises a bolt mechanism 12. The bolt mechanism 12 comprising a rotationally mounted bolt 14 and a rotary actuator 16 operationally coupled to the rotationally mounted bolt 14. The rotary actuator 16 is operable to rotationally withdraw the rotationally mounted bolt 14. The rotationally mounted bolt 14 is shown withdrawn in figure 25 and extended in figure 26. The lock 200 comprises a cam mechanism 18 and a movably mounted interference member 20 operationally arranged with the cam mechanism 18. The movably mounted interference member 20 is movable, by operation of the cam mechanism 18, into interference with the bolt mechanism 12 when the rotationally mounted bolt 14 is at least one of: withdrawn, and so prevent the rotational mounted bolt 14 from being extended; and extended, and so prevent the rotationally mounted bolt 14 from being withdrawn.

The lock 200 is in the form of a mortice lock. The lock 200 may be disposed in a mortice formed in a hinged barrier – examples of which include but are not limited to a gate and a door – a piece of furniture or other structure as desired and suitable. The rotary actuator 16 is configured to engage a torque transmitting bar in the form of a square cylinder for transmitting a torque from a handle. The square cylinder is in use simultaneously received in a square socket 11 defined by the rotary actuator 16 and another square socket defined by the handle. The torque transmitting bar may be engaged by handles on opposite sides of the lock 200, for example.

Alternatively, the torque transmitting bar may be engaged by only one handle on one side of the lock.

The movably mounted interference member 20 comprises a slidably mounted plate 22 attached to a finger 24, which in this but not all embodiments is integral of the slidably mounted plate 22.

Figures 27 and 28 comprise rear cut away perspective views detailing the interference member and the cam mechanism 18 of the lock 200. Operation of the cam mechanism 18 can slide the slidably mounted plate 22 into interference with the rotary actuator 16 of the bolt mechanism 12.

When in interference with the bolt mechanism 12, the finger 24 of the slidably mounted plate 22 interferes with the bolt mechanism 12. A tag 26 of the finger 24 is received in a cavity 28 defined by the rotary actuator 16 when the slidably mounted plate 22 interferes with the bolt mechanism 12. The cam mechanism 18 comprises a rotationally mounted cam 30 and a cam follower 32 attached to the interference member 20. The cam 30 is configured to be operationally coupled to a cylinder lock on one side of the movably mounted interference member 20. The cam 30 comprises a cylinder lock engaging feature 36 in the form of a ridge extending outwardly from cam plate 34. The cylinder lock engaging feature 36 rotationally locks with an end of the cylinder lock, which defines a slot for receiving the cylinder lock engaging feature 36. The position of the slot and ridge may be reversed. A user can insert a key into the cylinder lock operationally coupled to the cam 30 and rotate the key within the cylinder lock in a first rotational direction to actuate the cam 30 to rotate the cam 30. The cylinder lock may be, for example, for operation from inside of a building, and may be used to lock and unlock the lock from the inside of the building for egress from the building. The lock may be installed, however, for the cylinder lock to be operated from outside of the building to enable ingress.

The movably mounted interference member 20 interferes with the bolt mechanism 12 when the bolt 14 is extended. The tag 26 may be received by either cavity 28 when the bolt is extended and cavity 29 when the bolt 14 is withdrawn. The cavities are defined by the rotary actuator 16.

The cavity 28 is accessible to the finger 24 when the rotationally mounted bolt 14 is extended.

The cavity 29 is accessible to the tag 26 of the finger 24 when the rotationally mounted bolt 14 is withdrawn. Alternatively embodiments may have only one of the cavities 28,29. Consequently, depending on the configuration of the lock 200, the finger 24 can interfere with the rotary actuator 16 when the bolt is extended and/or retracted, locking the bolt in either extended or retracted positions.

The lock 200 comprises a sliding member 202, which is movable between a first position (shown in figures 26 and 27) and a second position (shown in figures 25 and 28) by operation of the rotary actuator 16. The rotary actuator 16 comprises a plurality of gear teeth 204 and the sliding member 202 comprises a rack 206 operationally coupled to plurality of gear teeth 204. Figure 31 shows an elevational view of the sliding member 202.

The sliding member 202 interferes with the cam mechanism 18 in only one of the first position and the second position to prevent the movably mounted interference member 20 being moved by the operation of the cam mechanism 18 into interference with the bolt mechanism 12. The sliding member 202 is configurable in a first configuration wherein the sliding member interferes with the cam mechanism in the first position and a second configuration wherein the sliding member does not interfere with the cam mechanism. The sliding member comprises two longitudinally displaced stop receivers 201, 203 in the form of threaded screw holes, whereby the sliding member 202 has the first configuration when one of the two stop receivers receives a stop 210 in the form of a screw and the sliding member has the second configuration when the other of the two stop receivers receives the stop 210 in the form of the screw.

In the configuration of figures 25 – 28, stop 210 is located in a lower stop receiver, so that the rotationally mounted cam 30 when rotated clockwise (for the view of figures 25 and 26), is stopped by the stop 210 when the sliding member 202 is in an upper position, as shown in figure 29. A rotationally mounted cam tag 212 which is bent out of the plane of the cam plate 34 is interfered with by the stop 210. Consequently, the lock 200 can be locked with the bolt 14 extended, but not withdrawn. Figure 30 shows another configuration of the sliding member 202, wherein the stop 210 is received by an upper stop receiver, so that the rotationally mounted cam when rotated clockwise is stopped by the stop 210 when the sliding member 202 is in a lower position.

The lock 200 may be configured without the stop 210 being received by either of the two longitudinally displaced stop receivers, so that the bolt 14 can be locked in the extended position (figure 26) and the retracted position (figure 25).

It will be appreciated that the stop and the stop receivers may take any suitable form, for example a peg that is received with an interference fit in either one of two sockets, a rivet and holes, a clip and sockets. The lock may not be reconfigurable in alternative embodiments, for example the screw may be welded in place or the sliding member may have a stop in the form of an integral tag.

The cam mechanism 18 comprises another cam follower 35 attached to the interference member . The cam 30 and the cam follower 32 are cooperatively arranged to move the interference member 20 into interference with the bolt mechanism 12, and the cam 30 and the other cam follower 35 are cooperatively arranged to move the interference member 20 out of interference with the bolt mechanism 12.

As seen in the rear views of figures 27 and 28, a cylinder lock can be coupled to other cam 40 for key operation of the rotary actuator, allowing key operation on the far side of the barrier in a manner similar and/or identical to that of lock 10.

Now that embodiments have been described, it will be appreciated that some embodiments may have some of the following advantages: • A lock that may have a bolt immobilisable in one of the extended and withdrawn position, but may not be otherwise locked, may be provided.

• A lock that may have a bolt immobilisable in one of the extended and withdrawn positions may be reconfigured for the bolt to be immobilisable in the other one of the extended and withdrawn positions, and vice versa.

• Inadvertent locking of the bolt in one of the extended and withdrawn positions, for example by slamming the hinged barrier, may be prevented.

Variations and/or modifications may be made to the embodiments described without departing from the spirit or ambit of the invention. For example: • The bar may alternatively have a hexagonal or other profile, or may be splined, and the rotary actuator may have a complementary configuration for rotary engagement with the bar.

• The finger may not be integral to the slidably mounted plate. The finger may be attached to the slidably mounted plate with a fastener.

• Cylindrical lock engaging features may alternatively comprise pin receiving apertures, pins, a key or keyway, or generally any suitable form.

• The movably mounted interference member may be rotationally mounted to be rotated into interference with the rotary actuator.

• The bolt pivot may be in the form of a boss integral with the rear portion of the casing.

The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive. Reference to a feature disclosed herein does not mean that all embodiments must include the feature.

Prior art, if any, described herein is not to be taken as an admission that the prior art forms part of the common general knowledge in any jurisdiction.

In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word “comprise” or variations such as “comprises" or “comprising" is used in an inclusive sense, that is to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.

Claims (24)

Claims 1.

1. A lock comprising: a bolt mechanism comprising a rotationally mounted bolt and a rotary actuator operationally coupled to the rotationally mounted bolt, the rotary actuator being operable 5 to rotationally withdraw the rotationally mounted bolt; and a cam mechanism independently operable of the bolt mechanism and a movably mounted interference member operationally arranged with the cam mechanism, the movably mounted interference member being movable, by operation of the cam mechanism, into interference with the bolt mechanism when the rotationally mounted 10 bolt is at least one of: withdrawn, and so prevent the rotationally mounted bolt from being extended; and extended, and so prevent the rotationally mounted bolt from being withdrawn. 15

2. A lock defined by claim 1 wherein the movably mounted interference member comprises a slidably mounted plate comprising a finger, the slidably mounted plate being slidable into interference with the bolt mechanism, such that the finger interferes with the bolt mechanism.

3. A lock defined by claim 2 wherein the finger is received in a cavity defined by the rotary 20 actuator when the slidably mounted plate interferes with the bolt mechanism.

4. A lock defined by any one of the claims 1 to 3 wherein the cavity is inaccessible to the finger when the rotationally mounted bolt is one of withdrawn and extended.

5. A lock defined by any one of the preceding claims wherein the cam mechanism comprises a rotationally mounted cam and a cam follower attached to the interference 25 member.

6. A lock defined by claim 5 wherein the cam mechanism comprises another cam follower, the cam and the cam follower are cooperatively arranged to move the interference member into interference with the bolt mechanism, and the cam and the other cam follower are cooperatively arranged to move the interference member out of interference 30 with the bolt mechanism.

7. A lock defined by either one of claim 5 and claim 6 wherein the cam is configured to be operationally coupled to a cylinder lock.

8. A lock defined by either one of claim 5 and claim 6 wherein the interference member comprises yet another cam follower, the cam is configured to be operationally coupled to 5 a cylinder lock on one side of the movably mounted interference member, and comprising another cam configured to be operationally coupled to another cylinder lock on another side of the movably mounted interference member, the other cam and the yet other cam follower being cooperatively arranged to move the interference member out of interference with the bolt mechanism. 10

9. A lock defined by claim 8 wherein the other cam and the rotary actuator are cooperatively arranged for the other cam to operate the rotary actuator.

10. A lock defined by claim 9 wherein the other cam comprises a plurality of elongate radial projections and the rotary actuator is configured to be engaged by the plurality of elongate radial projections for actuation thereby. 15

11. A lock defined by any one of the preceding claims comprising a pivotally mounted lever having an end adjacent the bolt mechanism and another end adjacent the movably mounted interference member, wherein the other end is positioned for stopping the movably mounted interference member being moved into interference with the bolt mechanism when the other end is engaged with the bolt mechanism. 20

12. A lock defined by any one of the preceding claims comprising a pivotally mounted stop biased into a path of the movably mounted interference member and so stop movement of the movably mounted interference member into interference with the bolt mechanism.

13. A lock defined by claim 12 wherein the cam mechanism and pivotally mounted stop are cooperatively arranged such that the cam mechanism moves the pivotally mounted stop 25 out of the path of the movably mounted interference member when the cam is operated.

14. A lock defined by any one of the claims 1 to 10 comprising a sliding member movable between a first position and a second position by operation of the rotary actuator, wherein the sliding member interferes with the cam mechanism in only one of the first position and the second position to prevent the movably mounted interference member being 30 moved by the operation of the cam mechanism into interference with the bolt mechanism.

15. A lock defined by claim 14 wherein the sliding member is configurable in a first configuration wherein the sliding member interferes with the cam mechanism in the first position and a second configuration wherein the sliding member does not interfere with the cam mechanism. 5

16. A lock defined by claim 15 wherein the sliding member comprises two longitudinally displaced stop receivers whereby the sliding member has the first configuration when one of the two stop receivers receives a stop and the sliding member has the second configuration when the other of the two stop receivers receives the stop.

17. A lock defined by any one of the claims 14 to 16 wherein the rotary actuator comprises a 10 plurality of gear teeth and the sliding member comprises a rack operationally coupled to the plurality of gear teeth.

18. A lock defined by any one of the preceding claims wherein the rotary actuator is configured to engage a torque transmitting bar for transmitting a torque from a handle.

19. A lock defined by any one of the preceding claims wherein the rotary actuator comprises 15 at least one gear tooth for engaging the movably mounted interference member, whereby operation of the rotary actuator actuates the at least one gear tooth to move the moveably mounted interference member out of engagement with the bolt mechanism.

20. A lock defined by claim 19 wherein the movably mounted interference member comprises a pin for engagement with the at least one gear tooth. 20

21. A lock defined by any one of the preceding claims comprising a mortice lock.

22. A lock comprising: a bolt mechanism comprising a rotationally mounted bolt and a rotary actuator operationally coupled to the rotationally mounted bolt, the rotary actuator being operable to rotationally withdraw the rotationally mounted bolt; and 25 a cam mechanism and a movably mounted interference member operationally arranged with the cam mechanism, the movably mounted interference member being movable, by operation of the cam mechanism, into interference with the rotary actuator and so immobilise the rotationally mounted bolt.

23. A lock comprising: 30 a bolt mechanism comprising a rotationally mounted bolt and a rotary actuator operationally coupled to the rotationally mounted bolt, the rotary actuator being operable to rotationally withdraw the rotationally mounted bolt; and a cam mechanism and a movably mounted interference member operationally arranged with the cam mechanism, the movably mounted interference member being 5 movable, by operation of the cam mechanism, into interference with the bolt mechanism when the rotationally mounted bolt is at least one of: withdrawn, and so prevent the rotationally mounted bolt from being extended; extended, and so prevent the rotationally mounted bolt from being 10 withdrawn.

24. A method for operating a lock, the method comprising the steps of: operating a rotary actuator of the lock to rotationally withdraw a rotationally mounted bolt of the lock; and operating a cam mechanism to move a movably mounted interference member of 15 the lock into interference with a bolt mechanism of the lock, the bolt mechanism comprising the rotationally mounted bolt, wherein the rotationally mounted bolt is at least one of: withdrawn, and so prevent the rotationally mounted bolt from being extended; 20 extended, and so prevent the rotationally mounted bolt from being withdrawn.