IE45800B1

IE45800B1 - Improvements relating to locks

Info

Publication number: IE45800B1
Application number: IE160278A
Authority: IE
Original assignee: Kelly E
Priority date: 1978-08-04
Filing date: 1978-08-04
Publication date: 1982-12-01
Also published as: GB2027111A; GB2027111B; IE781602L

Abstract

A lock and bolt assembly, particularly for use on roller shutters for lock-up shops and other business premises which comprises a cylinder lock of the "cam" type which is rotatable through 180 DEG between first and second catch positions (in both of which a key can be inserted into or withdrawn from the lock); a bolt 12 slidable in a direction perpendicular to the axis of the cylinder lock; and a cam plate 5, suitably of generally rectangular shape, mounted on the rear end of the cylinder of the lock so as to be rotatable with the cylinder, the cam plate 5 being arranged to engage behind the internal end of the bolt 12 to lock the bolt in an extended position when the cylinder lock is in the second catch position. Rotation of the cylinder lock to the first catch position withdraws the cam plate 5 from behind the end of the bolt 12 and enables the bolt to be retracted by means of a pin or other rigid element inserted into a hole in the bolt. In a second embodiment, a spring loaded flap is mounted on the bolt and extending beyond the internal end of the bolt so that in its rest position it engages with the cam plate. This flap can be pivoted by manual operation from the rear of the assembly so that the flap disengages from the cam plate to permit retraction of the bolt even while the cylinder lock remains in the second catch position.

Description

Improvements relating to locks The present invention relates to locks. The invention has been made to meet a need among manufacturers of shutters which are used to protecd the windows and doors of business premises, particularly lock-up shops. Such shutters are normally made of channel-shaped slats of aluminium or other metal which.can roll and unroll like a window blind with the vertical edges sliding in a pair of vertical channels.

A lock or locks must be provided at the bottom of such a shutter in order to secure it in the closed position. A variety of different kinds of lock have been used.for. this purpose, either »a single lock in the centre of the bottom rail of the shutter or two locks spaced apart at the side edges of the bottom rail. Such a lock normally has a bolt which engages a hole in one or both of the vertical channels.

A lock on a shutter should be strong and simple to operate while being protected against tampering or vandalism from the outside. It is also advantageous for a shutter manufacturer to have a lock which is easy to install and maintain.

Existing.locks do not meet these requirements and the lock of the present invention has been devised in order to overcome the problems of locks which are too complex and unreliable. The lock of the present invention is also useful in locations other than shutters.

The present invention provides a lock and bolt assembly comprising a cylinder lock the cylinder having first and second key-release positions in both of which a key can be inserted into and removed from the lock and being rotatable between said first and second key-release positions when a - 2 key is inserted in the lock, a cam. pi ate mounted on the rear.end of the cylinder of the lock so as to be rotatable with the cylinder, and a bolt slidable in a direction perpendicular to the axis of the cylinder lock, the cam plate engaging directly or indirectly behind the internal end of the bolt to lock the bolt in an extended position when the cylinder lock is in the second key-release position but withdrawing when the cylinder lock is in the first key-release position to permit the bolt to be pushed to a retracted position.

When the cam plate engages the internal end of the bolt directly, it preferably engages a head on the internal end of the bolt.

In some cases, such as a shop where the owner lives on or over the premises, it may be desirable to be able to retract the bolt from the rear of the assembly without turning the cylinder lock (which can normally only be operated by a key from the front of the assembly).

In one embodiment therefore the assembly incorporates means operable from the rear of the lock and bolt assembly to release the bolt from engagement with the cam plate while the cylinder lock is in the second key-release position.

Preferably, in this embodiment, the assembly has abutment means pivotally connected to the bolt adjacent the internal end thereof such that in its rest position it engages the cam plate when the bolt is in its extended position but which is movable to a second position in which it disengages from the cam plate to permit retraction of the bolt while the cylinder lock remains in the second key-release position.

More particularly, the abutment means comprises a spring-loaded flap pivotally mounted on the bolt and extending beyond the internal end of the bolt so that in its rest position it engages with the cam plate when the lock is in the second key-release position but is pivotable against the action of the spring to move into a second position in which it overrides 3q the cam plate to permit retraction of the bolt.

Preferably, the axis of the bolt intersects the cylinder lock at right angles to the axis of the cylinder lock. Preferably also the lock incor458C0 -, - 3 porates a catch mechanism to retain the bolt in its retracted position.

The invention is illustrated in the accompanying drawings in which: Fig. 1 is a rear elevation of a first embodiment of-a lock and bolt assembly showing the bolt in the retracted position; Fig. 2 is a plan view of the assembly of Fig. 1, also showing the bolt in the retracted position, and partially cut away; Fig. 3 is a rear elevation of the assembly of Fig. 1, showing the bolt in the extended position; Fig. 4 is a front elevation of the lock of Fig. 1, showing the bolt in the '10 extended position; Fig. 5 is a rear elevation of a second embodiment of a lock and bolt assembly according to the invention, showing the bolt in the extended position; Fig. 6 is a plan view of the assembly of Fig. 5, partially cut away, and showing the bolt in a retracted position; and Fig. 7 is a plan view of the assembly' of Fig. 5, showing the bolt in the extended position.

As shown in Figs. T - 4 of the drawings, the components of the lock and bolt assembly are mounted on a metal base plate 1 having screw holes 2 through which the assembly can be bolted or otherwise secured to a slat of a shutter (or to another suitable body). The base plate 1 is shaped to fit within the rear-facing channel of a shutter slat.

A cylinder lock 3 is mounted in the base plate 1 with the keyhole extending forwardly. The cylinder lock is of the cam type. It has a cylinder 4 in which spring-urged tumblers are mounted. When the key is not in posi25 tion in the lock, the tumblers stand proud of the surface of the cylinder along two diametrically opposed lines parallel to the axis of the cylinder. When the key is inserted, the tumblers are retracted into the cylinder until they are level with the surface. The cylinder is housed in a barrel having two diametrically opposed .axial recesses in its internal surface, the remainder of the surface fitting closely around the cylinder. When the tumbers stand prpud of the surface of the cylinder, they fit into the two recesses of the barrel. Thus the cylinder can be locked in either of 43800 , - 4 two key-release positions and can be rotated through 180° from one position to the other. Rotation of the key causes the cylinder to rotate.

The key can only be withdrawn in the two key-release positions. A stop is provided on the internal surface of the barrel to prevent the cylinder turning through more than 180°, Cylinder locks of this kind are commercially available, for example, under the name L & F Double Safe from Lowe & Fletcher.

The rear of the cylinder 4 has a cam plate 5 secured thereto by a screw 6. The cam plate 5 is of generally rectangular shape with rounded corners, the axis of attachment to the cylinder 4 being close to one of the short sides of the rectangle so that the greater part of the cam plate forms a wing 7 projecting from the rear of the cylinder at right angles to the axis of the cylinder.

A bolt 12 is slidable on the face of the base plate 1 being located in two brackets 13 riveted to the base plate 1. The internal end of the bolt 12 has a head 14 with a flange 15 on the side of the head remote from base plate 1. The head stand's proud of the rear surface of the bolt so as to project across the plane of cam plate 5.

Base plate 1 is penetrated by a slot 15 aligned with bolt 12. A hole 17 bored through bolt 12 is accessible from the front of base plate 1 via the slot 16 in both the extended and the retracted position of the bolt.

Base plate 1 is also penetrated by a hole 18 which, v/hen the bolt is in the retracted position, is aligned v/ith a catch mechanism 19 housed in the bolt. This catch mechanism comprises a spring-urged ball bearing housed in a cylindrical recess in the frontward face of bolt 12.

When the lock is being installed on a slat of a shutter (not shown), it is necessary to cut in the slat an aperture to receive the cylinder lock 3 and a slot to correspond with slot 16. The lock is secured to the slat near to one end of the slat so that bolt 12 projects beyond the end of the slat when the bolt is in the extended position. The bolt can then engage S 8 ΰ Ο in an aperture in a vertical channel in which the side of the shutter slides.

As shown in Figs. 1 and 2, when the assembly is in the open position, corresponding to the first key-release position of the cylinder lock 3, the wing 7 of the cam plate 5 is turned away from bolt 12. Bolt 12 can therefore be positioned in the retracted position and it is held in this position by the catch mechanism 19 engaging the hole 18 in the base plate 1.

When it is desired to close the lock and bolt assembly, a pin or other rigid element is inserted through slot 16 to engage hole 17 and the bolt 12 is then pushed to its extended position, extra pressure being applied initially on the pin (or other rigid element) to overcome the spring-urged catch mechanism. The extent of travel of the bolt is limited by a stop screw 20 on the rear face of the bolt which butts against one of the brack-ets 13. When the bolt 12 is in its extended position, the cylinder lock is turned by a key to rotate the cam plate through 180°.

As shown in Figs. 3 and 4, when the assembly is in the closed position, corresponding to the second key-release position of cylinder lock 3, the wing 7 of cam plate 5 is turned towards the bolt 12 and engages the head 14 of the bolt inside the flange 15. The cam plate 5 then prevents the bolt being retracted.

When it is desired to open the lock, cylinder lock 3 is turned back through 180° again, and the bolt can then be slid back to its retracted position by a pin or other rigid element inserted through slot 16.

Because the pin or other rigid element must be of small enough diameter to engage hole 17, it is likely to break if an attempt is made to force the lock. Because the bolt is aligned with cylinder lock 3, it is virtually impossible to cause the cam plate to rotate by pressure on the bolt unless the cylinder lock 3 is turned by the key.

The flat surface on the end of the wing 7 of the cam plate forms a flat on the cam at right angles to the axis of the bolt (which is itself aligned 4S8 ύθ - 6 with the cylinder lock) and the head of the bolt also has a flat surface at right angles to the axis of the bolt so that pressure by the bolt against the cam plate does not tend to rotate the cam plate.

If desired, the cam plate may be shaped to drive the bolt from retracted 5 to extended position when the cylinder lock is turned. If desired, also, the cam plate may carry hook means to engage the head of the bolt to retain it in the retracted position.

As shown in Figs. 5 - 7, a second embodiment of the invention has major components the same as those of the first embodiment shown in Figs. 1 ~ 4, and the same numerals are used for these components.

The internal end of the bolt 12 is provided with a flap 21, comprising two mounting lugs 22 disposed parallel to the upper and lower surfaces of the bolt, connected by means of a split pin 23 passing through the lugs 22 and a corresponding hole through the bolt 12, thus forming a pivot. One IE end 24 of the flap is bent over substantially at right angles to the axis of the bolt so that its outer surface may be brought into secure engagement with the wing 7 of the cam plate v/hen the lock assembly is in a ‘'closed” position. A recess 25 in the outer surface of the bolt 12 houses a spring 26 which engages against the inner surface of the other end of the flap 21. 2C As shown in Figs. 5 and 7, when the lock assembly/ιη the closed position, corresponding to the second key-release position of cylinder back 3 and the bolt 12 is extended, the wing 7 of the cam plate 5 is turned towards the internal end of the bolt and engages the end 24 of the flap 21. The cam plate 5, in engagement with tha flap 21, then prevents the bolt being retracted.

When it is desired to open the lock assembly from the outside, cylinder lock 3 is turned back through 180° again, and the bolt can then be slid back to its retracted position by a pin or other rigid element inserted through slot 16.

When it is desired to open the lock assembly from the inside (i.e. the rear of the assembly), the flap is caused to pivot about its fulcrum by 3800 - 7 pressing that end of the flap remote from the cam plate against the action of the spring 26. This permits the end 24 of the catch to override the wing 7 of the cam plate as shown in Fig. 6. The bolt 12 can now be retracted as the internal end of the bolt is received in the space between the wing 7 and the base plate 1. Thus, the lock can readily be opened from the inside without the use of a key. i In the locks utilized in the present invention, the key can be inserted into and withdrawn from the cylinder in both of the key-release positions. This is an advantageous feature of the invention because the owner of a lock-up shop or the like needs to be able to withdraw and retain his or her key when the security shutter is both closed and open. The cylinder lock is preferably a 10-lever cam lock adapted to receive a key having serrations on both edges.

Claims

1. A lock and bolt assembly comprising a cylinder lock, the cylinder having first and second key-release positions In both of which a key can be inserted into and removed from the lock and being rotatable between said first and second key-release positions when a key is inserted in the lock, a cam plate mounted on the rear end of the cylinder of the lock so as to be rotatable with the cylinder, and a bolt slidable in a direction perpendicular to the axis of the cylinder lock, the cam plate engaging directly or indirectly behind the internal end of the bolt to lock the bolt in an extended position v/hen the cylinder loc< is in the second keyrelease position but withdrawing when the cylinder lock is in the first key-release position to permit the bolt to be pushed to a retracted position.

2. A lock and bolt assembly according to claim 1, wherein tne cam plate engages the internal end of the bolt directly.

3. A lock and bolt assembly according to claim 2, wherein the cam plate engages a head on the internal end of the bolt.

4. A lock and bolt assembly according to claim 1 having means operable from the rear of the lock and bolt assembly to release the bolt from engagement with the cam' plate while the cylinder lock is in the second key-release position.

5. A lock and bolt assembly according to claim 4 having abutment means pivotally connected to the bolt adjacent the internal end thereof such that in its rest position it engages the cam plate when the bolt is in its extended position but which is movable to a second position in which it disengages from the cam plate to permit retraction of the bolt while the cylinder lock remains in the second key-release position.

6. A lock and bolt assembly according to claim E, wherein the abutment means comprises a spring-loaded flap pivotally mounted on the bolt and extending beyond the internal end of the bolt so that in its rest position it engages with the cam plate when the lock is in the second key-release 45300 - 9 position but is pivotable against the action of the spring to move into a second position in which it overrides the cam plate to permit retraction of the bolt.

7. A lock and bolt assembly according to any of the preceding claims, wherein the axis of the bolt intersects the cylinder lock at right angles to the axis of the lock.

8. A lock and bolt assembly according to any of the preceding claims, wherein the cam plate has a flat surface which lies at right angles to the axis of the bolt when the lock is in the second key-release position.

9. A lock and bolt assembly according to any of the preceding claims having a catch mechanism to retain the bolt in its retracted position.

10. A lock and bolt assembly according to any of the preceding claims, wherein the bolt has a hole adapted to engage a pin or other rigid pushing element.

11. A lock and bolt assembly according to any of the preceding claims, said assembly being mounted on a base plate having front and rear surfaces.

12. A lock and bolt assembly according to claim 11, wherein the bolt is slidable on the rear face of the base plate, the bolt has a hole adapted to engage a pin or other rigid pushing element, and the hole is accessible from the front of the ba$e plate via a slot which penetrates the base plate and which is such that the hole is accessible in both the extended and the retracted position of the bolt.

13. A lock and bolt assembly according to claim 11, wherein the base is shaped to fit within the rear-facing channel of a shutter slat.

14. A lock and bolt assembly substantially as described herein with reference to Figures 1 - 4 or 5 - 7 of the accompanying drawings.