Field of the Invention

The present invention relates to cylinder locks and in particular cylinder locks having improved security features.

Background to the Invention

Cylinder locks typically have a cam that is actuated by a lock driving member which drives the cam and thereby actuates a latch or other locking mechanism for locking a door or other leaf. Two examples of common lock cylinders are the“Euro profile cylinder” (often shortened to“Euro cylinder”) and the“Scandinavian Oval cylinder”.

Cylinder locks have been found to be vulnerable to attack by applying a lateral force to the front of the lock housing until the locks breaks into two pieces. This is known as“lock snapping”. A typical Euro cylinder lock is shown in Figures 1A to 1 C. The cylinder lock has a revolving cam B located in a cut-out A in the cylinder housing. Adjacent the cut-out A is a fixing hole C for receiving a fixing screw E for securing the cylinder lock to a door. The area around the fixing hole C is an area of weakness and when lateral force is applied to the front of the cylinder housing, the housing will typically snap in this area. Once the cylinder housing has broken, the front of the cylinder housing can be pulled away from the locked door, leaving the cam accessible, and therefore allowing entry through the door.

The present invention aims to provide a cylinder lock having improved security features.

Summary of the Invention

According to a first aspect of the invention there is provided a cylinder lock comprising: a cylinder lock housing for receipt within a bore in a support in use, the housing having a front end and a rear end, the housing having a first bore at its front end for receiving a first rotatable lock driving member for rotation within the first bore; a cam connectable to the first rotatable lock driving member for rotation therewith, said cam adapted to operate a locking mechanism on rotation of the cam; the cam having a first position and a second position, wherein the cam moves in a first direction relative to the support when moving from its first position to its second position; the cylinder lock further comprising biasing means for biasing the cam towards its second position; and holding means for holding the cam in its first position; the cylinder lock being adapted such that if the cylinder lock is tampered with by movement or breakage of the holding means, the cam is caused to move from its first position to its second position, the first position of the cam being an aligned position wherein the cam aligns with the locking mechanism such that it can operate the locking mechanism and the second position is a misaligned position wherein said cam is out of alignment with the locking mechanism and cannot operate the locking mechanism.

If the holding means is moved or broken so that it no longer functions to maintain the cam in its first position, the cam moves from its first position to its second position under the biasing action of the biasing means. Movement of the holding means may include removal of the holding means from the cylinder lock for example. The cylinder lock may be for mounting in any support, such as a closure. For example, it may be mounted in a leaf for a window or door. The bore for receiving the cylinder lock may be a bore formed directly in the closure or it may be a bore formed in the casing of a locking mechanism or handle assembly which is mounted on the closure. When the cam is in its first position a portion of the housing at its front end may protrude from a first side of the support, or it may be flush with the surface of the support or slightly recessed relative thereto. The holding means is preferably configured to be located at the front end of the cylinder lock in use. The holding means preferably engages a portion of the housing at or near the front end of the housing in use. Preferably as the cam moves from its first position to its second position it moves rearwardly relative to the support. In other words the cam moves in the direction that the rear end of the housing faces in use. Suitably the cylinder lock is adapted such that if the cylinder lock is tampered with by movement or breakage of the holding means, the cam is caused to move from its first position to its second position. The cylinder lock has a longitudinal axis running between its front and rear ends. The housing has a longitudinal axis aligned with that of the cylinder lock. The cylinder lock has front and rear ends (being front and rear ends respectively), lateral sides and a top and a bottom. Said first direction that the cam moves in from its first position to its second position is preferably an axial direction parallel with the longitudinal axis of the housing.

Preferably said cam is adapted to be carried by and move with the housing as the housing moves between a first position and a second position, wherein when the housing is in its first position the cam is in its first position and wherein when the housing is in its second position the cam is in its second position. The holding means may hold the cam in its first position directly or indirectly. For example, the holding means may hold the housing in its first position, thereby also holding the cam, which is mounted to the housing, in its first position. Therefore, if the holding means is moved or broken so that it no longer functions to maintain the housing in its first position, the housing moves from its first position to its second position under the biasing action of the biasing means, such that the cam is then out of alignment with the locking mechanism.

Suitably the cam is adapted to be carried by and move with the housing when the housing moves. When the housing is in its second position and the cam is out of alignment with the locking mechanism, the cam can no longer operate the locking mechanism and the cam is blocked from rotation by the casing of the locking mechanism. Therefore, it will be very difficult for someone to gain entry to the closure when the housing is in its second position. Even if this simply slows an intruder down, it is beneficial as a burglar will typically only spend a few minutes trying to break in before they give up.

Preferably the housing comprises a slot for receiving a fixing rod therethrough. The fixing rod is preferably receivable in holes in the support on either side of the lateral sides of the cylinder lock housing such that the fixing rod can be fixed non-movably relative to the support in use. The cylinder lock housing is preferably secured moveably relative to the support. The slot in the housing for receiving the fixing rod is shaped to allow the housing to slide frontwardly and rearwardly relative to the fixed fixing rod in use. The term “frontward” refers to a direction towards the front of the housing/cylinder lock and the term “rearward” refers to a direction towards the rear of the housing/cylinder lock. Preferably the front and rear of the housing/cylinder lock are opposing ends. It will be understood that the cylinder lock can be installed in a support with the front and rear ends facing in any direction. For example, when the cylinder lock is installed in a door, it can be installed with the front end of the cylinder lock facing away from either face of the door.

Preferably the slot comprises a throughole extending between opposing lateral sides of the housing. The fixing rod suitably extends through the throughole of the slot in the housing. The fixing rod is preferably received in the slot with the longitudinal axis of the fixing rod extending between the lateral sides of the housing along an axis orthogonal to the longitudinal axis of the housing. Preferably the slot comprises a planar slot. The planar slot preferably extends along a plane having first and second axes, the first axis being substantially parallel with the longitudinal axis of the housing and the second axis being parallel to an axis running between the lateral sides of the housing. The planar slot extends in a plane normal to an axis running between the top and bottom sides of the housing.

Preferably the slot has a sliding axis parallel to the longitudinal axis of the housing, the fixing rod having a width w1 along an axis parallel with the sliding axis when installed in the housing and the slot having a width w2 parallel with the sliding axis, the width w2 of the slot being longer than the width w1 of the fixing rod so that the housing can slide relative to the fixing rod along the sliding axis. The slot suitably has a front and rear end corresponding to the front and rear ends of the cylinder lock, the width w2 of the slot extending between its front and rear ends, the front and rear ends of the slot forming stops, preventing the housing from moving beyond its second position and first positions respectively. The fixing rod being received in the slot acts as a guide means as the housing moves forwardly and rearwardly. The cylinder lock may have a holding means that prevents the cylinder lock sliding rearwardly unless the holding means is broken or moved. The cylinder lock may also have a retaining means that prevents the cylinder lock sliding frontwardly after it has moved into its second position.

Preferably the cylinder lock further comprises a fixing rod shaped to be received within the slot such that the housing can translate along the longitudinal axis of the cylinder lock relative to the fixing rod.

Preferably at least a portion of the fixing rod is flattened, said at least a portion of the rod being for receipt within said slot. The fixing rod suitably has a longitudinal axis running between a first and a second end of the rod, the transverse cross-section of the rod (i.e. the cross-section orthogonal to its longitudinal axis) having a width along an axis substantially parallel with the longitudinal axis of the housing when installed therein and a height, the width being greater than the height.

Preferably the holding means for holding the housing in its first position comprises a flange member adapted to engage with the housing in use and extend transversely from it, the flange member being adapted to sit against a frontward facing surface of the support in order to maintain the housing in its first position. The frontward facing surface of the support could be a front surface of the locking mechanism or a front surface of the closure that the locking mechanism is mounted in.

Preferably the flange member comprises at least one opening for receiving a fixing member for fixing the flange member to the housing in use.

Preferably the flange member comprises first and second openings on opposing sides of the flange member, each opening being for receiving a set screw for frictionally engaging the housing. The first and second openings are preferably on opposing lateral sides of the flange member.

Preferably the flange member comprises a plate, the plate having an opening shaped and sized to receive the housing therethrough, and the housing comprising at least one groove adapted to receive part of the plate therein. The plate opening preferably has an edge which is receivable in said at least one groove in order to maintain the housing in its first position. The plate is preferably C-shaped.

Preferably the housing comprises a plurality of grooves, the cylinder lock being adapted so that the plate may be received in any one of the plurality of grooves, the grooves being arranged on a portion of the housing toward the front end of the housing. The grooves are preferably parallel to one another and equally spaced from one another. The parallel set of grooves are preferably arranged one after another along a line parallel with the longitudinal axis of the housing.

Preferably the biasing means for biasing the cylinder lock housing towards its second position comprises at least one compression spring. The or each compression spring is preferably a helical compression spring.

Preferably the biasing means comprises a helical compression spring received around part of the housing in use.

Preferably the biasing means further comprises a cradle attachable to the housing, said at least one compression spring being located between the cradle and the support in use. The cradle preferably comprises first and second openings on opposing sides of the cradle, each opening being for receiving a set screw for frictionally engaging the housing. The first and second openings are preferably on opposing lateral sides of the cradle. The cradle member has an opening shaped and sized such that the housing can pass therethrough

Preferably the cylinder lock further comprises retaining means for retaining the housing in its second position after it has moved into that position.

Preferably the retaining means comprises a locking plate for coupling with the housing via a ratchet mechanism permitting one way travel of the housing in a first direction relative to the support when the locking plate is coupled with the housing but not permitting travel of the housing in an opposite direction relative to the support. The ratchet mechanism of the retaining means suitably permits one way travel of the housing rearwardly relative to the support when the locking plate is coupled with the housing but not permitting travel of the housing frontwardly relative to the support. The ratchet mechanism prevents the housing from moving frontwardly relative to the support unless the locking plate is disengaged from the housing.

Preferably the housing comprises a plurality of ratchet teeth towards its rear end for cooperating with the locking plate in use. Each ratchet tooth preferably comprises a first surface angled relative to the housing, the first surface sloping towards said housing in a direction towards the rear end of the housing, and a second surface which slopes towards the housing in a direction away from the rear end of the housing, said second surface being more steeply sloped than said first surface. The locking plate is preferably adapted to sit against a rearward facing surface of the support and to cooperate with the ratchet teeth in order to prevent the housing from moving frontwardly.

Preferably the retaining means comprises a blocking member moveable between a first storage position in which it is contained substantially within the housing and a second extended position in which it extends from the housing, the blocking member being biased towards the second extended position, wherein when the housing moves from its first position to its second position, the blocking member is able to move from its first storage position to its second extended position, the blocking member being positioned so that when in its second extended position it can sit against a surface of the support in order to prevent the housing from moving. When the blocking member is in its second extended position it can preferably sit against a rearward facing surface of the support in order to prevent the housing from moving frontwardly. The blocking member is preferably spring biased into it second extended position. The blocking member is preferably located towards the rear end of the housing.

Preferably the housing comprises a plate receiving slot, the slot being shaped and oriented to receive a planar plate for reinforcing the housing. The slot preferably extends along a plane arranged between opposing lateral sides of the housing and between the front and rear ends of the housing. The plate receiving slot is preferably arranged so that a plate received in it will extend substantially orthogonally to the support when the cylinder lock is installed therein. The plate receiving slot is preferably located between the slot for receiving the fixing rod and the cam.

Preferably the housing comprises first and second pin receiving bores, each for receiving a pin, said pin receiving bores each having a longitudinal axis substantially orthogonal to the plane of the plate receiving slot.

Preferably cylinder lock further comprises a plate shaped and sized to be received in said plate receiving slot. The plate preferably has first and second apertures which align with said first and second pin receiving bores in the housing when the plate is installed in the housing, said first and second apertures being for receiving pins therethrough. The cylinder lock may further comprise first and second pins to be received in said first and second pin receiving bores.

Many cylinder locks of the prior art having a sacrificial portion configured to break away from the remainder of the housing if an attempt is made to snap the housing. Many of the embodiments of the invention do not have a housing with a sacrificial portion since cylinder locks of the invention will be harder to access and therefore break since once the lock is tampered with the housing moves to a position wherein it is less accessible. An advantage of providing a cylinder lock wherein the housing does not have a sacrificial front portion is that if a cylinder lock of the invention is tampered with, the cam simply moves to its second position (rather than the housing breaking, if it included a housing with a sacrificial front portion). Therefore cylinder locks of the present invention will typically not need to be replaced after the lock is tampered with. However, cylinder locks according to the invention may of course have housings with sacrificial front portions to further improve security.

In some embodiments the housing comprises a sacrificial portion and a remainder portion, the sacrificial portion being configured for breaking away from the remainder portion if an attempt is made to snap the housing. The sacrificial portion is suitably separated from the remainder portion by a line of weakness in the housing, such that housing breaks at said line of weakness before failing anywhere else when a sufficient lateral force is applied thereto. The line of weakness preferably comprises a cut provided through part of the housing. The sacrificial portion is preferably located at the front of the housing. The line of weakness is preferably located frontwards of the cam.

Preferably said cam has a radially projecting cam lever for operating the locking mechanism upon rotation of the cam, the cylinder lock further comprising a bolt, the cam lever having a recess for receiving said bolt, the bolt being moveable between a first disengaged position in which it is disengaged from the recess and a second engaged position in which at least a portion of the bolt is received in the recess, the cam being prevented from rotation when the bolt is in the second engaged position.

According to a further aspect of the invention there is provided a cylinder lock comprising: a cylinder lock housing having a front end and a rear end, the housing having a first bore at its front end for receiving a first rotatable lock driving member for rotation within the first bore; a cam connectable to the first rotatable lock driving member for rotation therewith, said cam having a radially projecting cam lever for operating a locking mechanism upon rotation of the cam, the cylinder lock further comprising a bolt, the cam lever having a recess for receiving said bolt, the bolt being moveable between a first disengaged position in which it is disengaged from the recess and a second engaged position in which at least a portion of the bolt is received in the recess, the cam being prevented from rotation when the bolt is in the second engaged position.

The bolt suitably acts as a night latch that can be used to easily lock the closure at night. If the cylinder lock is configured to be operated internally using a key, the night latch bolt can be engaged to prevent the closure from being opened from the outside, without the user needing to locate the key. The night latch may be an electric piston controlled via a smartphone app. The bolt may be a solenoid bolt. Preferably the bolt is disposed so that it is accessible at the rear end of the housing. The bolt is therefore accessible on the inside of a closure to operate as a night latch. The cylinder lock described above may be combined with a motor, the cylinder lock including a rotatable member which is coaxial and connectable to the cam for rotation therewith, the assembly including a drive coupling arranged to cause rotation of the rotatable member in response to operation of the motor.

According to a further aspect of the invention there is a provided a cylinder lock assembly comprising: a cylinder lock housing for receipt within a bore in a support, the housing having a front end and a rear end, the housing having a first bore at its front end for receiving a first rotatable lock driving member for rotation within the first bore; a cam connectable to the first rotatable lock driving member for rotation therewith, said cam adapted to operate a locking mechanism on rotation of the cam; a motor; the cylinder lock including a rotatable member which is coaxial and connectable to the cam for rotation therewith, the assembly including a drive coupling arranged to cause rotation of the first rotatable member in response to operation of the motor.

Preferably the rotatable member is located between said cam and the rear end of the housing. The rotatable member preferably has gear teeth on at least part of its outer surface. Suitably the rotatable member is preferably located on the internal side, rather than the external side, of the cylinder lock. The motor may be mountable on the rear side of the support.

Preferably the rotatable member has gear teeth and the drive coupling includes a gear wheel for engagement with the gear teeth of the rotatable member in order to rotate the rotatable member.

Preferably the rotatable member is adapted to be driven by a pulley mechanism. The drive coupling is suitably a pulley drive coupling. Preferably the cylinder lock further comprises a blocking pin operable by the motor to move between a first rest position and a second engaged position in which the blocking pin engages the rotatable member, preventing the rotatable member from being rotated. Preventing the rotatable member from being rotated in turn prevents the cam from being rotated, preventing the cylinder lock from operating the locking mechanism. In embodiments in which the rotatable member has gear teeth, the blocking pin will engage with the gear toothed rotatable member when the blocking pin is in its second engaged position.

According to a further aspect of the invention there is provided a kit for a handle assembly according to any preceding aspect of the invention.

In the context of the present invention, the term“mounting” means connecting or joining, either directly or by means of an intermediate or auxiliary element.

In the context of the present invention, the term“connecting” means mounting or joining, either directly or by means of an intermediate or auxiliary element.

It is to be understood that the mere use of the term“first” does not require that there be any“second,” and the mere use of the term“second” does not require that there be any “third,” etc.

Brief Description of the Drawings

Figure 1A is a side view of a prior art cylinder lock with a key and fixing screw exploded from it;

Figure 1 B is a close-up view of a weak point in the cylinder lock housing of the lock of Figure 1A;

Figure 1 C is a front view of the cylinder lock of Figure 1A.

The preferred embodiments of the present invention will now be more particularly described, by way of example, with reference to the accompanying drawings, wherein:

Figure 2 is an exploded view of a cylinder lock according to an embodiment of the invention adjacent a locking mechanism for a closure; Figure 3 is a side view of a cylinder lock according to an embodiment of the invention; Figure 4A shows a side view of a locking mechanism together with close-up views of the locking mechanism and an embodiment of a cylinder lock;

Figure 4B shows the cylinder lock of Figure 4A;

Figure 4C shows a fixing rod of the cylinder lock of Figure 4A;

Figure 5A shows a side view of a cylinder lock according to an embodiment of the invention installed in a door with the cylinder lock in aligned mode;

Figure 5B shows the cylinder lock of Figure 5A with the fixing rim removed;

Figure 5C shows a perspective view of the cylinder lock of Figure 5A with part of the locking mechanism cut away;

Figure 5D shows a perspective view of the cylinder lock of Figure 5A;

Figure 5E shows a perspective view of the cylinder lock of Figure 5A but in misaligned mode;

Figure 5F shows an enlarged view of Figure 5E;

Figure 6A shows a side view of a cylinder lock according to an embodiment of the invention installed in a locking mechanism with the cylinder lock in aligned mode;

Figure 6B shows a side view of the cylinder lock of Figure 6A with the fixing rim removed and the cylinder lock in misaligned mode;

Figure 6C shows a side view of a cylinder lock according to an embodiment of the invention installed in a locking mechanism with the cylinder lock in aligned mode;

Figure 6D shows a perspective view of the cylinder lock of Figure 6C;

Figure 6E shows a top view of the steel plate from the cylinder lock of Figure 6C;

Figure 6F shows a side view of the steel plate from the cylinder lock of Figure 6C;

Figure 7 A shows a side view of a cylinder lock according to an embodiment of the invention installed in a locking mechanism with the cylinder lock in aligned mode;

Figure 7B shows a side view of a cylinder lock according to another embodiment of the invention installed in a locking mechanism with the cylinder lock in aligned mode;

Figure 7C shows a side view of the cylinder lock of Figure 7B in misaligned mode;

Figure 8A shows a perspective view of a cylinder lock according to an embodiment of the invention, the cylinder lock having a night latch feature;

Figure 8B shows a perspective view of the cylinder lock of Figure 8A with the housing partially cut away and the night latch disengaged;

Figure 8B shows a perspective view of the cylinder lock of Figure 8B with the housing partially cut away and the night latch engaged; Figure 9A shows a side view of a cylinder lock according to an embodiment of the invention installed in a door with the cylinder lock in aligned mode, the cylinder lock having a plate as a holding means;

Figure 9B shows a perspective view of the cylinder lock of Figure 9A;

Figure 9C shows a front view of the cylinder lock of Figure 9A;

Figure 9D shows a front view of the plate of Figure 9A;

Figure 9E shows a side view of the plate of Figure 9A;

Figure 10A shows a perspective view of a cylinder lock according to an embodiment of the invention installed in a door with the cylinder lock in aligned mode, the cylinder lock having a plate as a retaining means comprising a ratchet mechanism;

Figure 10B shows a perspective view of the cylinder lock separate from the door;

Figure 10C shows a close-up side view of the ratchet mechanism;

Figure 10D shows a close-up perspective side view of the ratchet mechanism;

Figure 10E shows a side view of the assembly of Figure 10A with the fixing rim removed and displaced from the assembly;

Figure 10F shows a perspective view of a cylinder lock according to an embodiment of the invention installed in a door with the cylinder lock in aligned mode, the cylinder lock having a plate as a retaining means comprising a blocking member;

Figure 10G shows the cylinder lock of Figure 10F in misaligned mode;

Figure 10H shows a side view of the cylinder lock of Figure 10F;

Figure 101 shows a side view of the cylinder lock of Figure 10G;

Figure 11 A shows a perspective view of a cylinder lock according to an embodiment of the invention installed in a door with the cylinder lock in aligned mode, the assembly further including a motor for operating the cylinder lock;

Figure 1 1 B shows a perspective view of the assembly of Figure 1 1 A with the door partially cut away;

Figure 1 1C shows a close-up view of the assembly of Figure 1 1 B;

Figure 12A shows a perspective view of a cylinder lock according to an embodiment of the invention installed in a door with the cylinder lock in aligned mode, the assembly further including a motor for use in blocking the cam from rotating;

Figure 12B shows a perspective view of the assembly of Figure 12A with the door partially cut away;

Figure 12C shows a close-up view of the assembly of Figure 12B and with the motor pin shown engaged with the cylinder lock. Description of the Preferred Embodiments

The present embodiments represent currently the best ways known to the applicant of putting the invention into practice. But they are not the only ways in which this can be achieved. They are illustrated, and they will now be described, by way of example only. Common features between the assemblies of the different figures are referenced by common reference numerals.

Referring to Figure 2, a cylinder lock 10 is shown. The particular lock shown in the figures is a Euro profile cylinder, although it will be appreciated that the present invention is not limited to a Euro profile cylinder lock but can be employed in other types of cylinder lock. The cylinder lock 10 has a housing 12, which may also be referred to as a cylinder casing, adapted to be received in a bore in a support such as a locking mechanism for a closure such as a door or window leaf. As with other Euro profile cylinder locks, the housing 12 has a keyhole shaped cross-section, however the housing may have other cross-sectional shapes. The closure that the cylinder lock is mounted in will have an internal side and an external side. The closure may be in the external perimeter of a building, in which case the external side faces outside. Alternatively, the closure may be an internal closure, such as an internal door separating one part of a building from another, but it can still be considered to have an internal side and an external side, the cylinder lock being adapted to operate a locking mechanism to prevent intruders on the external side of the closure from opening the closure. The housing 12 has a front end 12a and a rear end 12b and the housing is configured to be installed with the front end 12a facing away from the external side of the closure and the rear end 12b facing away from the internal side of the closure. The housing 12 has a longitudinal profile which extends between the front end 12a and the rear end 12b. The terms "front" and "rear" are used in this specification and appendant claims with reference to the orientation of the cylinder lock during actual use of the apparatus described. The terms“front”,“rear”,“side”,“top”,“bottom� � etc are provided as an aid to describing the relative location of the various components and are not meant to be limiting in any way.

The housing 12 comprises a top section 23 comprising a bore at either end having a through passage, said bores separated by a cam opening 21 , and a cam 20 located in the cam opening 21 , between the bores. The housing 12 further comprises a lower section 25 extending along the length of the cylinder lock and comprising a bridge section joining the bores at either end across the cam opening 21.

The housing 12 defines a first bore 14 within which is mounted a first rotatable lock driving member 16 in use. The first rotatable lock driving member 16 is a lock drum comprising a pin tumbler locking mechanism, defining a keyhole, the first rotatable lock driving member being actuable by a key 18 as is known in the art and which will not be described further. The key 18 can be used to rotate the first rotatable lock driving member 16.

The cam 20 is co-axial with and connectable to the first rotatable lock driving member 16 for rotation therewith. The cylinder lock may include a second and further cams, but in this embodiment the cylinder lock has one cam. The cam 20 has a generally cylindrical body 22 and a radially projecting protrusion 24 as a cam lever. The cylinder lock 10 is received in a correspondingly shaped bore 8 in the casing 6 of a locking mechanism 4 installed in the closure (not shown). The locking mechanism is mounted in use adjacent a face plate 5 which is configured to sit against the edge of the closure (e.g. a door edge) when installed therein. Rotation of the first rotatable lock driving member 16 causes the cam 20 to rotate, thereby actuating a locking bolt/latch 2 of the locking mechanism 4. The cam 20 is located partway between the front end 12a and rear end 12b of the housing. For example, the cam 20 may be midway between the front end 12a and rear end 12b of the housing.

The cylinder lock shown in Figure 2 is a double cylinder lock, but it may alternatively be a single cylinder lock. With the double cylinder lock shown in Figure 2, the lock can be operated from either side of the leaf. The lock housing 12 has a second bore 15 at the rear end of the housing receiving a second rotatable lock driving member 17. The second rotatable lock driving member 17 is co-axial with and connectable in use to the cam 20, such that the second rotatable lock driving member 17 can drive the cam. The second rotatable lock driving member 17 may be configured to be key operated or hand-operated, for example comprising a“thumb-turn” mechanism, as is well-known in the art. As is known in the art, the double cylinder lock may include a clutch mechanism to provide the ability for the cam 20 to be operated from both sides of the leaf.

The cam 20 has a first position as shown in Figure 5D and a second position as shown in Figure 5F in which the cam 20 has moved rearwardly relative to the closure. The cam 20 is carried by housing 12, which is moveable between a first position shown in Figure 5D and a second position shown in Figure 5F, therefore moving the cam between its first position and second position when the housing moves between its first position and second position. The housing 12 is biased in the second position and the cylinder lock includes holding means for holding the housing 12 in its first position. The cylinder lock is adapted such that if the cylinder lock is tampered with by movement or breakage of the holding means, the cylinder lock transforms from its first position to its second position. When the housing 12 is in its first position, the cam 20 is also in its first position and aligns with the locking mechanism such that it can operate the locking mechanism. The first position may therefore be referred to as a first aligned position and the cylinder lock may be referred to as being in an aligned mode when the housing and cam are in this position. When the housing is in its second position, the cam 20 is displaced into its second position such that it no longer aligns with the locking mechanism and the cylinder lock cannot operate the locking mechanism when the housing 12 is in this position. The second position may therefore be referred to as a second misaligned position and the cylinder may be referred to as being in a misaligned mode when the cylinder lock has been tampered with and the housing / cam is in the second position. In the embodiments described herein the casing 6 of the locking mechanism blocks the cam lever 24 from rotating when the cam 20 is in its second misaligned position. Therefore the locking mechanism cannot be operated when the cam 20 is in the second misaligned position. These features will be further described below.

The housing 12 does not have a transverse screw hole to receive a fixing screw to secure the cylinder to the closure as is typical in prior art cylinder locks like that of Figure 1A. Referring to Figure 2, the housing 12 has a slot 30 for receiving a fixing rod 32. The slot 30 has a throughole extending between opposing lateral sides 12c of the housing, the throughole of the slot having a bore axis running between the lateral sides 12c which is substantially orthogonal to the first bore 14 of the housing 12. The slot 30 has openings 34 in each lateral side of the housing 12. The slot 30 is elongated along the longitudinal axis of the first bore 14 of the housing 12, the openings 34 each having a longitudinal axis parallel with the first bore 14. The fixing rod 32 has a flattened shank portion 32a. In this embodiment the cross-section of the shank portion 32a transverse to its longitudinal axis has a width w1 (its major axis) that is longer than its height hi (its minor axis). The slot 30 has a width w2 which is longer than the width w1 of the flattened shank portion 32a of the fixing rod and a height h2 which is just larger than the height hi of the shank portion 32a of the fixing rod, so that the housing 12 can slide back and forth axially relative to the fixed fixing rod 32 in use. The engagement of the fixing rod 32 in the slot 30 guides the housing 12 as it moves between its first aligned position and its second misaligned position. The engagement also provides a front and rear stop, preventing the housing 12 from moving frontwardly beyond its first aligned position or rearwardly beyond its second misaligned position.

The fixing rod 32 is securable to the locking mechanism 4 (it may alternatively be securable directly to the closure if the cylinder lock is mounted directly in a closure). The fixing rod 32 has a head 32b and a rounded shank portion 32c arranged between the head and the flattened shank portion 32a. The rounded shank portion 32c sits in an aperture 35 in the faceplate 5 of the locking mechanism 4, the outwardly flanged shaped head 32b sitting against the faceplate 5 when installed therein. This secures the housing 12 movably relative to the locking mechanism 4 and therefore also relative to the closure in which the locking mechanism is installed, allowing the housing 12 to slide back and forth within bore 8. The cylinder lock may be referred to as a floating cylinder due to its ability to float (i.e. translate) frontwardly and rearwardly relative to the closure.

Referring to Figure 2 in some embodiments the holding means for holding the housing 12 in its first aligned position comprises a fixing rim 40 adapted to mount to the housing 12 in use and to extend outwardly from it in a plane substantially orthogonal to the longitudinal axis of the housing. The fixing rim 40 is adapted to sit against the front of the closure 7 in order to maintain the housing 12 in its first aligned position as shown in Figure 5A. The fixing rim 40 therefore forms a flange member extending outwardly from the housing 12. Referring to Figure 2, the fixing rim 40 has a key hole shaped opening 42 shaped so that the first rotatable lock driving member 16 can be accessed by the key 18 in use. The opening 42 need not be key hole shaped, as long as users can access the first rotatable lock driving member 16 with the key 18 in order to operate the lock when the fixing rim 40 is in place. The fixing rim 40 has first and second openings 44 on opposing lateral sides, each opening 44 receiving a set screw 46, also known as a grub screw, for fictionally engaging the housing 12 so that the fixing rim 40 can be secured relative to the housing 12. This fixes the housing 12 relative to the closure and holds the housing 12 in its first aligned position. Other means for securing the fixing rim to the housing can of course be employed. The cylinder lock has biasing means for biasing the housing 12 towards its second misaligned position, as will now be described. Any spring means which biases the housing 12 away from the locking mechanism or closure can be employed. Referring to Figure 7B, a compression spring 50 is shown which serves as the biasing means that may be used in any embodiment. The spring 50 is received around part of a barrel of the cylinder lock rearward of the cam 20, the housing 12 having an elongate cam opening 21 and the spring 50 being received in the cam opening 21 (or it may be received in a separate opening). The spring 50 has a rear end which engages the housing 12 in use and a front end which engages the casing 6 of the locking mechanism in use, thereby biasing the housing 12 away from the locking mechanism 4. If the holding means that maintains the housing 12 in its first aligned position is moved or broken, such as via tampering with the cylinder lock, then the compression spring 50 will cause the housing 12 to spring rearwardly to its second misaligned position. Preferably when in the second position, no part of the housing 12 will protrude from the front of the closure. Therefore a person tampering with the cylinder lock will not be able to grab the housing 12 in order to try to apply a force to it in order to snap it. The movement of the housing 12 into the second misaligned position is rather like a booby trap; if a person tries to tamper with the front of the cylinder lock to try to snap the lock for example, the cylinder lock springs rearwards such that the person will no longer be able to access the lock in order to try to snap it. When the housing is in the second position, even if a person trying to gain entry can access the retracted housing, the cam 20 is misaligned relative to the locking mechanism and is blocked from rotation, therefore the cam 20 cannot be turned and therefore the locking mechanism cannot be operated.

In alternative embodiments the holding means may be other than a fixing rim 40 as described above, or the holding means may comprise means in addition to the fixing rim 40. For example, Figure 2 shows a plate 47 which may be used instead of or as well as the fixing rim 40. The plate 47 is C-shaped and is sized and shaped such that the mouth fits around the top section 23 of the housing 12. Referring to Figures 9A and 9B, the housing 12 has a plurality of grooves 48 spaced along part of its length, at or near the front end of the housing, adapted to receive the back 47a of the mouth of the plate 47 therein. The grooves 48 run transverse to the longitudinal axis of the cylinder lock 10. The back 47a of the mouth of the plate 47 has a straight edge in this embodiment, but it may have a curved edge. The thin plate 47 is sized to fit within any one of the grooves 48. When the housing is positioned in its first aligned position, if a plate 47 is placed flush against the front of the closure, engaged in one of the grooves 48, this will retain the housing 12 in its first aligned position. The provision of a plurality of grooves 48 provides for optimal positioning of the housing 12 relative to the closure, depending on the width of the closure. If the plate 47 is removed (e.g. by someone tampering with the lock), as with the fixing rim 40, the housing 12 will spring rearward into its second misaligned position.

In alternative embodiments the biasing means may be other than the compression spring 50 as described above. For example, referring to Figure 2, a cradle 52 including one or more compression springs 54 may be used. The cradle 52 is C-shaped and is shaped and sized to fit around the housing 12, with the side arms of the cradle 52 extending up the lateral sides of the lower section 25 of the housing 12. The cradle 52 is attachable to the housing using suitable fixings. The cradle 52 has first and second openings 56 on the side arms of the cradle, each opening being for receiving a screw 57 for engaging the housing 12 so that the cradle 52 can be fixed relative to the housing 12. The housing 12 has corresponding openings 56a for receiving the screws 57. In this embodiment three compression springs 54 are arranged so that once installed they are disposed between the cradle and a rear face 6a of the casing of the locking mechanism 4, as shown in Figure 3. If the holding means that holds housing 12 in its first aligned position is removed or broken, then the compression springs 54 will cause the housing 12 to spring rearwardly to its second, misaligned position.

Referring to Figure 7B, in addition or instead of the biasing means described above, the cylinder lock may include an internal compression spring 58 fitted within the housing 12 which is configured to be disposed between an internal surface of the housing 12 and the fixing rod 32 to bias the housing 12 away from the fixing rod 32 which is fixed in position relative to the locking mechanism 4.

The cylinder lock preferably includes retaining means for retaining the housing 12 in its second misaligned position if the cylinder lock has been tampered with, so that a person wanting to gain access cannot grab the front end 12a of the housing and pull it frontward in order to try to snap the housing. The retaining means may be described as a lock off feature as it effectively locks the housing 12 in the second misaligned position. Referring to Figures 10A to 10E, the retaining means may comprise a locking plate 60 for coupling with the housing 12 via a ratchet mechanism permitting travel of the housing rearwardly but not frontwardly relative to the locking mechanism 4. Referring to Figure 2, the locking plate 60 is a thin C-shaped plate shaped to be received around the transverse cross- section of the top section 23 of the housing 12. The housing 12 has a plurality of ratchet teeth 62 spaced apart from one another in a line along on the top of its outer surface. The ratchet teeth 62 are disposed rearward of the cam 20, towards the rear end of the housing. The ratchet teeth 62 may be on a surface of the housing 12 that is integrally formed with the rest of the housing or on a separate housing part that is assembled to a main housing portion. Each ratchet tooth 62 has a first surface 62a angled sloping towards the housing in a direction towards the rear end 12b of the housing 12 and a second surface 62b sloping towards the housing in a direction away from the rear end 12b of the housing, the second surface 62b being more steeply sloped than the first surface 62a. Referring to Figure 10A, the locking plate 60 is configured to sit against the rear of the closure and to cooperate with the ratchet teeth 62 in order to prevent the housing from moving frontwardly.

In order to reactivate the cylinder lock ready for aligned use after it has been transformed into its second misaligned position, the retaining means needs to be released so that the housing 12 can be moved frontwards relative to the closure. This can be done simply by removing the plate 60, such that the housing 12 is free to move frontwards within its bore 8. If a key is put in the keyhole of the first rotatable member 16, the key 18 can be used to pull the housing 12 frontwards.

Figures 10F to 101 show an alternative retaining means for retaining the housing 12 in its second misaligned position once it has moved into that position. In this embodiment the cylinder lock has a blocking member 64 moveable between a first storage position (as shown in Figure 10H) in which it is contained substantially within the housing 12 and a second extended position in which it extends from the housing 12 (as shown in Figure 101). The blocking member 64 is biased towards its second extended position. When the housing 12 is in its first aligned position, the blocking member 64 is held in its first storage position by the casing 6 of the locking mechanism. The casing 6 obstructs the blocking member 64 from extending from its storage position as shown in Figure 10H. When the housing 12 moves to its second misaligned position, the blocking member 64 is carried by the housing 12 rearwardly and out of the casing 6 of the locking mechanism, so that it is no longer obstructed by the casing 6, allowing the blocking member 64 to move into its second extended position as shown in Figure 101. The blocking member 64 comprises an enlarged head portion 64a and a shank portion 64b around which a compression spring 65 is arranged to bias the blocking member 64 into its second extended position. The blocking member 64 is arranged between the cam 20 and the rear end of the housing. In order to move the housing back into its first aligned position after it has been moved into its second misaligned position as shown in Figure 101, the blocking member 64 can be manually pushed by a user from its second extended position into its first storage position and the housing 12 pushed frontwards.

Referring to Figures 6C to 6F the cylinder lock may further include features for reinforcement of the housing. In this embodiment the reinforcement feature is a plate 70 that is received in a slot 72 in the lower section of the housing between the cam opening 21 and the slot 30. The plate 70 has an elongate axis extending parallel with the longitudinal axis of the housing 12 when assembled thereto, the plane of the plate 70 extending orthogonally to the closure when installed therein. The plate 70 has first and second pin receiving apertures 74 which align with first and second pin receiving bores 76 in the housing 12 when the plate 70 is installed in the housing 12, the apertures 74 and bores 76 being for receiving first and second pins 78 therein. The steel plate 70 spans across the housing 12 to provide reinforcement against snapping of the housing. The pins extend parallel with the closure and are configured to accommodate forces if the cylinder lock is attacked, avoiding breakage of the housing 12. The plate 70 and pins 78 are preferably made of steel.

Referring to Figures 7A and 7B, the housing may optionally include a sacrificial portion 12d at the front end of the housing and a remainder portion 12e, the sacrificial portion being configured for breaking away from the remainder portion if an attempt is made to snap the housing. The sacrificial portion 12d is separate from the remainder portion 12e by a line of weakness 79 comprising a cut provided through the housing 12. The line of weakness is provided frontwards of the cam 20. If despite the retraction of the housing 12 following tampering with the front of the cylinder lock, a person manages to grasp the front end of the housing allowing lateral force to be applied to the housing, only the sacrificial portion 12d of the housing will snap off. The line of weakness 79 is spaced away frontward from the cam 20, therefore the cam 20 remains in the intact portion of the housing even if the sacrificial portion 12d is snapped off.

Referring to Figures 8A to 8C, the cylinder lock may optionally include a night latch. The night latch is a latch that can be locked from the internal side of the closure, wherein if the night latch is locked, the cylinder lock cannot be operated from the external side of the closure. The night latch is a bolt 80 engageable in a recess 82 in the cam lever 24. The bolt 80 is moveable between a disengaged position in which it is disengaged from recess 82 as shown in Figure 8B and an engaged position in which at least a portion of the bolt 80 is received in recess 82 as shown in Figure 8C, preventing the cam 20 from rotating relative to the housing 12 and therefore preventing the locking mechanism 4 from being operated. The rear end of the bolt 80 provides a push button 81 that can be pushed by a user to move the bolt 80 into the engaged position. The bolt 80 is pulled rearwardly by the user to move the bolt into the disengaged position. In other embodiments the night latch may be an electrically operated piston, controlled via a smartphone app. For example, a bolt may be a solenoid bolt.

In other embodiments, instead of the housing being moveable between a first position and a second position and thereby carrying the cam into its second misaligned position if the holding means is moved or broken, the cam may be moveable from a first aligned position to a second misaligned position if the holding means is moved or broken and the housing may remain fixed. In such embodiments the cam therefore moves relative to the housing between its first aligned position and second misaligned position. In such embodiments the cylinder lock has a suitable holding means for holding the cam in its first aligned position, the cylinder lock being adapted such that the cam moves into its second misaligned position if the holding means is moved or broken. For example, the holding means may be moved by removing it from the cylinder lock, causing the cam to move to its second misaligned position under the biasing action.

Referring to Figures 1 1A to 12C, the cylinder lock may have features that are operated remotely by a motor that may be controlled remotely, for example via a smartphone app. In a first embodiment, referring to Figures 11A to 11C the cam 20 can be controlled remotely to rotate in order to lock and unlock the locking mechanism using a motor 90. The system includes a drive coupling arranged to cause rotation of the cam 20 in response to rotation of a drive shaft (not shown) in the motor 90. The cylinder lock includes a rotatable member 91 which is coaxial and connectable to the cam 20 so that the cam 20 rotates as the rotatable member 91 rotates. In a preferred embodiment as shown in Figures 1 1A to 11 C rotatable member 91 has gear teeth 91 a on its outer surface adapted to be driven by a gear wheel 92 associated with the motor 90 as an output gear. As the motor is operated, the gear wheel 92 will rotate. The motor is mounted relative to the cylinder lock housing 12 such that the gear wheel 92 engages with the gear teeth of rotatable member 91 , allowing the cam 20 to be operated by the motor 90. The rotatable member 91 can be rotated in a first direction and in an opposite direction in order to lock and unlock the locking mechanism respectively.

In an alternative embodiment the rotatable member 91 may be configured to be driven by a pulley mechanism operated by motor 90 rather than by a gear mechanism.

Referring to Figures 12A to 12C, in another embodiment, instead of controlling locking and unlocking of the locking mechanism, the motor 90 can be used to provide a lock means which prevents the cam 20 from turning. The motor 90 has a pin 94 which extends therefrom, which is operable by the motor to move between a first rest position as shown in Figure 12B and a second engaged position in which the pin 94 engages the gear teeth 91a of the rotatable member 91 as shown in Figure 12C. When the pin 94 is in the second engaged position, the rotatable member 91 is prevented from rotating, thus preventing the cam 20 from rotating and preventing the locking mechanism from being operated from the external side of the closure, for example via the key. The pin 94 may be any sort of slidable bolt which may be operated remotely, for example via a smartphone app, such as a solenoid bolt.

Various of the features disclosed herein can be used in combination with one another as appropriate. It should be noted that embodiments of the invention have been described herein by way of example only, and that modifications can be made within the scope of the claims. It should be further noted that each of the many advantageous features described above may be employed in isolation, or in combination with any one or more other features.