GB2054729A - Mounting cylinder locks - Google Patents

Abstract

A cylinder lock body 1 e.g. an axial pin-tumbler lock is adapted to be inserted within a host housing having internal longitudinal grooves. The lock body 1 has a pair of keyways 11 cut into the lock casing and a profiled key 12 is inserted on the lock shaft 9 such that the edges 13a of the key engage the keyway slots 11 and project beyond the surface of the lock body 1 such that the lock body has a pair of radially projecting lugs beyond the keyways. After securing a drive boss to the shaft to retain the key 12, the lock body 1 is inserted in a lock housing having internal grooves in which the profiled key lugs engage to prevent rotation of the lock body with respect to the host housing upon actuation of the lock by an appropriate key. The lock shaft 9 can however rotate and thus actuate the bolt mechanism. The grooved housing is ideally from a disc tumbler lock and the invention thus provides a way of replacing a disc tumbler mechanism with a more secure pin-tumbler lock. <IMAGE>

Description

SPECIFICATION Improvements in or relating to radial lock assemblies This invention relates to a radial lock assembly in which a radial lock body is positively housed within a disc-tumbler lock housing.

Conventional disc tumbler lock housings are generally cylindrical with a pair of oppositely disposed internal grooves (disc-ways) and conventional radial lock mechanisms are substantially cylindrical.

In order for a lock assembly of this type to function it is necessary that the radial lock body is secured with respect to the lock housing to prevent relative rotation upon actuation by the appropriate key. Various methods have been proposed to meet this objective but they either require precision accuracy or are subject to failure or are time consuming and costly.

It is an object of this invention to provide a radial lock assembly in which a radial lock body is prevented from rotating with respect to its host housing and is easily separable therefrom.

According to this invention there is provided a lock assembly comprising a radial lock inserted within a cylindrical housing having a pair of internal longitudinal grooves, the radial lock body being prevented from rotation relative to said housing by means of a profiled key located around the pin barrel shaft and having portions adapted to engage a pair of keyways in the radial lock body and the grooves in said housing such that the pin barrel shaft is rotatable with respect to the housing upon operation of the radial lock.

One preferred cylindrical housing is a disc tumbler lock housing from which the disc tumbler plug assembly has been removed.

The radial lock may comprise a conventional cylindrical mechanism in which the pin barrel and associated shaft are mounted within a cylindrical body or casing and are rotatable with respect to such body or casing by operation of the lock with the necessary key.

The profiled key may be of planar bar configuration, the two ends of which engage the radial lock body keyways, or planar disc shaped with projecting formations which engage the keyways.

The keyways (slots) in the lock body are preferably located diametrically opposite at the end of the casing remote from the key entrance.

The profiled key may have an aperture through which the pin barrel shaft extends and may be located between the spring barrel and drive boss components of the radial lock.

An advantage of the invention is that direct replacement of pin tumbler lock mechanisms may be made in place of the disc tumbler plug. This creates a high security lock which may be placed or replaced in the environment for which the disc tumbler outer housing shape is specifically intended.

By way of example only, reference will now be made to the accompanying drawings, illustrating an embodiment and in which: Figure 1 is a cross-sectional view of a radial lock, Figure 2 is an isometric view of a radial lock with profiled key, Figure 3 is an isometric view of a radial lock with modified profiled key, and Figure 4 is a view of a suitable disc-tumbler housing.

As shown in Figure 1 a radial lock comprises a body or casing 1 of cylindrical shape with key entry aperture 8. A pin barrel 2 mounted within the body is connected to an axially extending shaft 9 which projects beyond the body 1. This shaft receives by rigid connection related components of the radial lock mechanism such as a drive boss (not shown). The extending shaft 9 also passes through a spring barrel 3 rigidly connected to the body 1 by a securing pin 7. The spring barrel receives a plurality of pins 4 which are separated from springs 6 in the spring barrel by bottom pins 5.

By inserting the appropriate key into the lock via the aperture 8 and turning the key, the pin barrel 2 shaft 9 and all other related components such as the drive boss secured to the shaft 9 rotate with respect to the radial lock body 1 to lock or unlock the mechanism as the case may be.

Referring to Figures 2 and 3, the radial lock cylindrical casing 1 has a flanged key entrance end 10 and a pair of oppositely disposed keyway slots 11 cut into the casing 1 at the drive boss end 1 7.

The pin barrel shaft 9 extends through the spring barrel 3 and this shaft is rotatable with its related, affixed components (not shown) upon operation of the radial lock by an appropriate key.

A profiled key 12, generally rectangular and with curved edges 13, has a central shaft receiving aperture 14. This key is inserted through the shaft 9 to lie adjacent the spring barrel 3 such that the key end portions 1 3a engage the keyways 11 in the lock casing 1 and stand proud of the casing to form two oppositely disposed projecting lugs.

Figure 3 shows a modified profiled key 15 of substantially disc shape with projecting lugs 1 6.

This key 1 5 is also arranged to be placed over the shaft 9 through its aperture 14 and is an improved fit within the casing 1, having a circular diameter corresponding to that of the spring barrel 3.

Radially extending lugs 16 with curved edges 17 are a close fit within the keyways 11 in the lock casing 1 and also protrude beyond the surface of the casing 1.

In each case, the pin barrel shaft 9 is a loose fit within the key aperture 14 and the lugs 16 or edges 1 3a are a close fit within the keyways 11.

After insertion of the profiled key, the radial lock assembly is fitted within a host housing.

Figure 4 illustrates a preferred cylindrical housing 18 which is a disc tumbler lock housing with the disc tumbler plug assembly removed (not shown).

The cylindrical housing 18 is provided with a pair of diametrically opposite longitudinal grooves 19, which are profiled to have a curved surface 20.

One end 21 of the housing is adapted to receive the radial lock assembly complete with profiled key (not shown). In positioning the radial lock casing, the projecting lugs of the profiled key are arranged to enter and engage the housing grooves 1 9 whereupon the radial lock is fully inserted until the flanged edge 10 thereof (Figures 2 and 3) engages the end 21 of the housing 18.

A drive boss may be rigidly secured to the shaft immediately after the profiled key has been correctly inserted, such that the profiled key lies between the drive boss and the spring barrel. The drive boss may have a maximum external diameter corresponding to the external diameter of the radial lock casing. With the drive boss attached, the profiled key is securely held in position and the radial lock with its drive boss may be inserted into the cylindrical housing whereby the drive boss partially extends beyond the remote end of the housing 18. In this position, all other related components of a complete lock assembly are fitted to the drive boss such that the radial lock cannot be withdrawn from the housing without dismantling.

Once fully assembled, the profiled key projecting lugs engaging the housing grooves prevents rotation of the radial lock casing with respect to the cylindrical housing and thus operation of the radial lock external key rotates the pin barrel shaft and other components affixed thereto to provide a locking or unlocking function.

Lock apparatus in accordance with the invention is a more effective and cheaper way of converting a disc tumbler lock to a radial, high security lock without the need for precision drilling and pegging and the rigid, strong profiled key resists deformation and failure.

Claims (12)

1. A lock assembly comprising a radial lock body inserted within a cylindrical housing having a pair of internal longitudinal grooves, the radial lock body being prevented from rotation relative to said housing by means of a profiled key located around the radial lock pin barrel shaft and having portions adapted to engage a pair of keyways in the radial lock body and the grooves in said housing such that the pin barrel shaft is rotatable with respect to the housing upon operation of radial lock.

2. A lock assembly according to Claim 1, wherein the radial lock body includes a flanged key entry end and drive boss rigidly affixed to its shaft.

3. A lock assembly according to either preceding claim, wherein the housing is a disc tumbler lock housing.

4. A lock assembly according to any preceding claim, wherein the housing grooves are diametrically opposite and include a curved surface.

5. A lock assembly according to any preceding claim, wherein the profiled key is of planar configuration and includes lugs which project beyond the surface of the radial lock body.

6. A lock assembly according to Claim 5, wherein the profiled key is in the form of a bar with curved edges adapted to engage the housing grooves.

7. A look assembly according to claim 5, wherein the profiled key is disc shaped with radially extending lugs.

8. A lock assembly according to Claim 6, wherein the disc portion of the profiled key is a close fit within the radial lock casing.

9. A lock assembly according to any preceding claim, wherein the keyways are diametrically opposite at the end of the radial lock casing remote from the key entrance.

10. A lock assembly according to any preceding claim, wherein the profiled key is situated between the radial-lock spring barrel and drive boss.

11. A lock assembly according to any preceding claim, wherein the profiled key has an aperture through which the radial lock shaft extends.

12. A lock assembly constructed and arranged to function substantially as herein described with reference to and as illustrated in any of Figures 2, 3 or 4 of the accompanying drawings.