GB2459094A

GB2459094A - Lock having drive plate blocked following release of trigger member held by cylinder barrel

Info

Publication number: GB2459094A
Application number: GB0806347A
Authority: GB
Inventors: Terry Jackson; Paul Jelly
Original assignee: Paddock Fabrications Ltd
Current assignee: Paddock Fabrications Ltd
Priority date: 2008-04-08
Filing date: 2008-04-08
Publication date: 2009-10-14
Anticipated expiration: 2028-04-08
Also published as: GB2459094B; GB0806347D0

Abstract

A door lock 10 comprises a cylinder barrel (figure 1, 12) operable to activate movement of a drive plate 14 of a locking mechanism. The cylinder barrel extends through a lock casing 16. The lock casing incorporates a blocking mechanism including a trigger member 34 held in a primed position against a spring 35 by location of the cylinder barrel in the casing. A blocking piece 38 is moveable in response to biasing action of the spring, when said trigger member 34 is released, to engage and prevent subsequent movement of the drive plate 14. A second trigger member may be prodded on an opposite side of the lock to the first trigger member. The drive plate 14 may comprise a recess 40 that is aligned with the blocking piece then the drive plate is in the locked position. The trigger member and cylinder barrel may have complementary surface engaging each other to hold the trigger member in the primed position. A setting screw 42 may be provided to prime the blocking member.

Description

Security Lock The present invention relates to a lock, and more particularly to a lock of a type suitable for use on doors, windows or the like, and having a security locking mechanism.

Premises, whether household, business or industrial, face the ever-present threat of breaking and entering'. Doors and windows are often the first point that criminals will attack in an attempt to force entry into premises. Although modern door locks make this much more difficult, these remain vulnerable to breakage by the more persistent or ingenious attacker.

Known locking devices, of the type typically employed for locking and securing doors and windows -particularly multi-point locking patio doors, typically comprise an arrangement of metal plates in a lock casing through which a cylinder barrel lock is inserted. The cylinder barrel typically contains a locking mechanism such as a pin-tumbler, wafer tumbler or disc tumbler mechanism. By inserting the correct key into the key slot in the end of the cylinder barrel, the locking mechanism may be opened to allow the cylinder barrel to move rotationally. The cylinder barrel connects to a thrower or cam that engages and moves the locking mechanisms in a manner that is well known in the art.

It is well-known that cylinder barrels have some inherent weakness and can be broken fairly easily. Although external cylinder guards can be added, these are often either relatively easy to remove, or are an unsightly additions, spoiling the appearance of the door.

* It is an aim of the present invention to provide an improved door lock. *.*.

S **S.

* According to the present invention there is provided a door lock of a type comprising a cylinder barrel operable to activate movement of a drive plate of a locking mechanism. The cylinder barrel extends through a lock casing, the lock casing S..... . . . . . . . . * tncorporating a blocking mechanism including a tngger member held in a primed position against a spring by location of the cylinder barrel in the casing. A blocking piece is moveable, in response to biasing action of the spring, when said trigger member is released, to engage and prevent subsequent movement of the drive plate.

It is an advantage that the lock incorporates a blocking mechanism, so that should the cylinder barrel be broken, the trigger element is no longer held against the biasing action of the spring so that the blocking piece is driven by the spring to engage the drive plate. Subsequent movement of the drive plate is prevented by the presence of the blocking piece.

In embodiments of the invention, the drive plate comprises a recess that is aligned with the blocking piece when the drive plate is in the locked position.

In embodiments of the invention the trigger member has a surface shaped to correspond with a surface of the cylinder barrel such that the corresponding surfaces engage one another to hold the trigger member in the primed position.

Embodiments of the invention further comprise setting means for setting the blocking mechanism into the primed position. The setting means may comprise a setting screw for pushing the blocking piece and trigger member against the spring to prime the blocking mechanism.

Embodiments of the invention further comprise first and second trigger members, wherein each trigger member is on an opposite side of the lock and is held in a primed position against a spring by location of the cylinder barrel in the casing. The blocking mechanism is operable to be activated when either of the first or second trigger members is released. * ** * S S * *S

* The invention will now be described, by way of example, with reference to the * : accompanying drawings, in which: S... *I*

Figure 1 is an end view of a lock, with cover removed, comprising a blocking :. * mechanism in the nominal or primed position after insertion of a cylinder barrel.

Figure 2 is a perspective view of the lock of fig. 1, prior to insertion of a cylinder barrel.

Figure 3 is an end view of the lock of fig. 1, prior to insertion of a cylinder barrel.

Figure 4 is a perspective view of the lock of fig. 1, comprising a blocking mechanism in the primed or armed position.

Figure 5 is a perspective view of the lock of fig. 1, after partial removal of a cylinder barrel.

Figure 6 is an end view of a lock comprising a blocking mechanism in the fired or triggered position after partial removal of a cylinder barrel.

Referring to figure 1, a door lock 10 is of a type comprising a cylinder barrel 12. The cylinder barrel 12 is operable to move a drive plate 14 of a locking mechanism of the type typically employed for locking and securing doors and windows. Locks of this type may be used, for example, with multi-point or single-point locking mechanisms used on commercial or domestic entrance doors. The drive plate 14 is configured to move (vertically up or down as shown in figure 1) between an unlocked and a locked position whereby it activates additional locking mechanisms (not shown). A covering facia (not shown) has been removed from the figures to expose the principal components of the lock 10.

The cylinder barrel 12 extends through an opening 17 that has been cut out of a lock casing 16. The cylinder barrel 12 is typically formed from metal and additionally comprises a rotatable barrel section 18 in which a locking mechanism such as a pin-tumbler, wafer-tumbler or disc tumbler mechanism is housed, although it may be appreciated that other suitable locking mechanisms may be employed as known in the art. A key (not shown) may be inserted into the key slot 20 to activate the locking * * mechanism and facilitate rotational movement of the barrel section 18. The cylinder barrel 12 connects to a thrower 21 or cam that engages a further locking mechanism in * *** a manner that is well known in the art. The further locking mechanism activates * : * movement of the drive plate 14. It is also known that a clutch assembly (not shown) within the cylinder barrel 12 may operate at the thrower 21 to allow the thrower 21 to be operated from either side of the cylinder lock 12 where two barrel sections 18 are :. employed to allow locking of the door to be performed independently from both sides.

The cylinder barrel 12 typically has a Euro Profile (or Euro Cylinder) shape, although oval or substantially circular profiles are also known in the art and may be employed within the lock 10.

As shown in figure 2, where the cylinder barrel 12 has not yet been inserted into the opening 17, the lock casing 16 connects to a faceplate 22 via welding or fastening means generally at an angle perpendicular thereto, although it may be appreciated that the faceplate 22 and the lock casing 16 may be formed as a single piece or as more than two pieces. The lock casing 16 acts as a support for the connection or insertion of additional components as requiredldesired. As an example, the opening 17 is cut out of the lock casing 16 and is shaped to accommodate the cylinder barrel 12.

As shown in figures 1, 3 and 6, the drive plate 14 has a recess 40 of a generally rectangular shape cut out of a lower portion of the plate. It will be appreciated that when the lock is unlocked, the drive plate will move upwards (as shown in the figures) so that the recess 40 will move to a higher position relative to the other lock components shown. The function of the recess will become apparent from the discussion below.

With reference to figure 3, a spacer element 30 is connected to the lock casing 16 via fasteners 32 (e.g. rivets or screws). The lock 10 contains a blocking mechanism including a first trigger element 34 that acts against a biasing spring 36 (as shown in figure 1 and omitted from figures 2-6 for clarity) located within a recess 35 between the trigger element 34 and the spacer element 30. The biasing spring 36 would typically be a helical compression spring, although other types of spring or biasing means may be used. The trigger element 34 is in the form of a plate or block and is * ** configured to move within a correspondingly shaped cut away in the spacer element 30. The trigger element 34 also includes a curved or shaped surface 37 with a shape that corresponds with a part of the cylinder barrel 12, so that the cylinder barrel 12 holds the trigger element 34 in a primed position in which the spring 36 is * compressed.

The blocking mechanism also includes a blocking piece or element 38 that is * : moveable in response to the biasing action of the spring 36 and via the abutment of the trigger element 34. When the drive plate 14 is in a locked position, as shown in figure 1, the recess 40 in the drive plate 14 is aligned with the blocking element 38 such that the blocking element 38 (when triggered as described below) can slide into the recess 40 to engage the drive plate and prevent it from moving. The blocking mechanism may additionally feature a projection 39 that is shaped to engage a correspondingly shaped keyway in the covering facia (not shown) to ensure that the blocking element can only be moved in one direction. A setting screw 42 passes through a hole 44 in the faceplate 22 and the gearbox spacer 30.

With reference to the figures, the setting of the device will now be described. Figure 3 shows the lock 10 before insertion of the cylinder barrel 12. In order to allow the cylinder barrel 12 to be inserted through the opening 17, the blocking mechanism must be primed into the position shown in figure 3. The setting screw 42 is screwed in and pushes the blocking element 38 away from the faceplate 22. This moves the trigger element 34 to compress the spring 36 into the position shown in figure 3. In this position, the shaped surface 37 is in alignment with the corresponding region of the shaped opening 17, allowing insertion of the cylinder barrel 12 through the opening 17 into the position shown in figures 1 and 4. With the cylinder barrel 12 installed, the setting screw 42 may be retracted. After retraction of the setting screw 42 the mechanism is armed as the trigger element 34 is held in position against the action of the spring 36 by the presence of the cylinder barrel 12.

In the event of attack or damage to the cylinder barrel 12, resulting in complete or partial removal of the cylinder barrel 12, the blocking mechanism is released and the blocking element 38 engages with the drive plate 14 in the recess 40 to block movement of the drive plate 14. With the blocking element 38 engaged in the recess * * 40, further movement of the drive plate 14 is prevented thereby fixing the drive plate 14 in the locked position and preventing unlocking of the door. An example of partial * * removal of the cylinder barrel 12 is shown in figures 5 and 6. *e** ****

Figure 5 shows a perspective view of the lock 10 where the underside of the cylinder barrel 12 is no longer in abutment with the curved surface 37 of the trigger element : :* 34. As may be seen more clearly in figure 6, the resultant disengagement of the cylinder barrel 12 releases the trigger element 34 that moves within the spacing element 30 due to the action of the spring 36. This movement, due to the abutment between the trigger element 34 and the blocking element 38 also causes the movement of the blocking element 38 into the recess 40 to engage the drive plate 14 thereby preventing movement of the drive plate 14 and securing the lock 10.

Preferably, the blocking mechanism includes a second trigger element 34a that ensures that removal of the cylinder barrel 12 in either direction results in the triggering or activation of the blocking mechanism to secure the lock. It may also be appreciated that although the blocking element 38 and the trigger element 34 are shown as two separate pieces, they could be formed as one piece, although this may render the blocking mechanism prone to a manual reset that pushes the elements (34, 38) against the spring 36 to release the engagement between the blocking element 38 and the drive plate 14. In the present invention, attempting to move the trigger element 34 back to the nominal position against the action of the spring 36 leaves the blocking element 38 in engagement with the drive plate 14 and maintains the security of the lock 10. The lock may, however be reset by the insertion and action of the setting screw 42 to reset the lock 10 into the position shown in figure 1. * ** *I * * *. S... * I II.. I... S...

S * *e * * S

S

Claims

Claims: 1. A lock of a type comprising a cylinder barrel operable to activate movement of a drive plate of a locking mechanism, wherein the cylinder barrel extends through a lock casing, the lock casing incorporating a blocking mechanism including a first trigger member held in a primed position against a spring by location of the cylinder barrel in the casing and a blocking piece moveable in response to biasing action of said spring, when said first trigger member is released, to engage said drive plate and prevent movement thereof.
2. A lock according to claim 1 further comprising a second trigger member held in a primed position against said spring by location of the cylinder barrel in the casing, said second trigger member being on an opposite side of the lock to said first trigger member, whereby the blocking mechanism is moveable in response to the biasing action of the spring when either of said first or second trigger members is released.
3. A lock according to claim 1 or claim 2, wherein said drive plate comprises a recess that is aligned with said blocking piece when the drive plate is in the locked position.
4. A lock according to any preceding claim, wherein the trigger member has a surface shaped to correspond with a surface of the cylinder barrel such that the corresponding surfaces engage one another to hold the trigger member in the primed position. * **
5. A lock according to any preceding claim, further comprising setting means for * * setting the blocking mechanism into the primed position. *.S. I...
6. A lock according to claim 5 wherein the setting means comprises a setting * screw for pushing the blocking piece and trigger member against the spring to prime : the blocking mechanism. * *