GB2305963A

GB2305963A - Security indicator locks

Info

Publication number: GB2305963A
Application number: GB9520524A
Authority: GB
Inventors: Cheuk Fai Ho
Original assignee: Individual
Current assignee: Individual
Priority date: 1995-10-04
Filing date: 1995-10-04
Publication date: 1997-04-23
Anticipated expiration: 2015-10-04
Also published as: GB2305963B; GB9520524D0

Abstract

A security lock has a rotatable knob (10) to actuate the lock mechanism. A keypad acts as a security device and enables rotation of the knob (10) if a correct code is input. In the event of a failure of the security device, a key (1) is provided to enable rotation of the knob (10). The key (1) engages in a keyhole (3) and enables rotation of the knob (10) irrespective of the condition of the security device. The keyhole (3) is generally concealed behind a cover (2) which is received within a recess (4) provided in the door knob (10). The cover (2) is made of a frangible material. When the override key (1) is used it is inserted into the keyhole (3) by breaking the cover (2) so that the fact that the key has been used to open the lock mechanism is visually indicated.

Description

IMPROVEMENTS IN OR RELATING TO SECURITY LOCKS The present invention relates to security locks.

There is often a need to control access to an area, such as a room or a safe, and it is known, for example, to provide security locks so that only those who know the code can open an access door. Such a security lock may incorporate, for example, a mechanical device having a number of coded keys and may enable unlocking of the lock mechanism only if those keys are actuated according to a preset code. Additionally and/or alternatively, the security lock may incorporate an electronic control accessed by way of a keypad, or by inserting a preprogrammed memory device such as a magnetic card or an IC card. As with mechanical locks, electronically controlled security locks require the input of an appropriate code to enable opening of the lock.

Of course, difficulties arise if the security lock fails in any manner.

It is an object of the invention to enable access to an area controlled by a security lock even upon failure of that lock.

According to the present invention there is provided a security lock comprising a lock mechanism which is normally in its locked condition, actuating means arranged, when enabled, to put the lock mechanism into its unlocked condition, and security means controlling the enablement of said actuating means, wherein said security lock further comprises override means for enabling said actuating means irrespective of the condition of said security means, and indicator means for indicating when the override means have been employed.

In an embodiment of the invention, the override means enable unlocking of the lock even if the security means fails, whilst the indicator means show that the override means has been used.

In a preferred embodiment, the override means comprises a key engageable within a keyhole provided in the security lock such that use of the key enables the actuating means.

It will be appreciated that whether the security lock is used to control access to a space within a building, or within a safe or the like, the key will preferably be a master key or pass key available only to supervisors and other selected personnel.

Security locks are generally only provided where it is necessary to secure the space to which they enable access.

This means that in the event of a failure it is necessary to give an indication of that failure. Certainly, it is important to know when the override means have been used, and this is the function of the indicator means.

The indicator means may be implemented in any appropriate manner. For example, the indicator means may comprise alarm means arranged to provide a visual or audible alarm signal upon use of the override means.

In a preferred embodiment, which is useful where the override means is a key, said indicator means may comprise means arranged to be altered or moved by use of the key.

Preferably, detecting means may be provided to detect or log any use of the override means.

In a preferred embodiment, the override means comprises a key engageable within a keyhole in the lock, and the indicator means comprise a cover for the keyhole.

The keyhole cover conceals the keyhole when access to it is not required. It may be arranged for the keyhole cover to sufficiently conceal the keyhole that passers by are not made aware of its existence. When access to the keyhole is required, this may be by moving the cover and/or by damaging the cover. For example, the cover may be readily pierced and hence the key can be inserted through the cover into the keyhole with resulting damage to the cover. Alternatively, the cover may be pivotably mounted in position so that it may be swung out of its keyhole covering position when it is required to insert the key.

A security lock of the invention may incorporate any appropriate lock mechanism. For example, the lock mechanism may be mechanically operated. Thus, the actuating means may be enabled mechanically by inputting a code into the lock, for example, by pressing a number of manually operable keys provided.

Additionally and/or alternatively, the security lock may be electrically controlled. The security means may then comprise, for example, processor means and a user interface, actuation of the interface by a user in an appropriate manner being able to enable the actuating means. The user interface may comprise a keypad, for example, or the security means may be further comprised of a reader for reading a magnetic card, IC card, or other code carrying device.

Embodiments of the present invention will hereinafter be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 shows a perspective view of an actuating knob for a door lock embodying a security lock of the invention, and Figure 2 shows a perspective view of an alternative embodiment of a door lock.

The present invention relates to a security lock (not shown). Such a lock generally comprises a lock mechanism, arranged to be in a normally locked condition, and a security device to control the actuation of the lock mechanism. The security device may be a keypad which is operated mechanically and arranged such that if a user inputs a preset code actuation of the lock mechanism by rotation of a door knob is enabled.

An electrically controlled lock mechanism is described and illustrated in our co-pending application No.

9507261.7, and the contents of that specification are incorporated herein by reference. In the earlier application, the security device is electronic and enables rotation of a door knob to actuate a lock mechanism by inputting a code into the security device by way of a keypad or by inserting an IC card.

However the security lock is arranged to operate, it is necessary to provide means to enable unlocking of the lock mechanism if the security lock fails. Such a mechanism is illustrated in Figure 1 which shows a knob 10 which, upon rotation thereof, actuates the lock mechanism.

The knob 10 may be arranged in normal use, to be normally non-rotatable, but enabled to rotate by the security device provided.

In the event of a failure of the security device, a key 1 is provided to enable rotation of the knob 10. In this respect, the key 1 is arranged to engage within a keyhole 3 provided in the knob 10, and is generally arranged to enable rotation of the knob 10 irrespective of the condition of the security device. This means that the key 1 can be used not only in the event of a failure, but also as a pass key.

Of course, a security lock is generally only provided where it is essential to secure the space controlled by the lock mechanism. It is, therefore, important to know if the security device has been overridden or bypassed.

In the embodiment of Figure 1, the keyhole 3 is generally concealed behind a cover 2 which is received within a recess 4 provided in the door knob 10. It will be appreciated that when the cover 2 is in position in the recess 4, the keyhole 3 is concealed. In this embodiment, the cover 2 is made of a frangible material. It is intended that the override key 1 is used simply by inserting the key 1 through the cover 2 into the keyhole 3.

This breaks the cover 2 so that the fact that the key has been used to open the lock mechanism is visually indicated.

Figure 2 shows a further implementation of the invention. In Figure 2, parts which are the same or similar to those shown in Figure 1 have been given the same reference numerals. As in the embodiment of Figure 1, a keyhole 3 is provided in a door knob 10 and is operable by way of a key 1. However, in this embodiment, the keyhole 3 is concealed by a movable cover 22 which is pivotably mounted on the door knob 10 about a pivot pin 5. The cover 22 would normally be positioned across the end of the door knob 10 to conceal the keyhole 3. When access to the keyhole 3 by the key 1 is required, the cover 22 is pivoted about the pin 5 to reveal the keyhole 3, as is shown in Figure 2.

An indication that the cover 22 has been moved to enable insertion of the key 1 may be provided mechanically or electrically. For example, the cover 22 may be encased in a frangible material (not shown) whereby pivoting thereof breaks that material. Additionally and/or alternatively, electrical means may be provided to recognise the pivoting of the cover 22 and to make a record of the fact that it has been pivoted. Such electrical means may detect movement of the cover 22 by detecting movement at the pivot axis 5, for example. Alternatively, appropriate light sensitive means may be provided at the end of the keyhole 3.

Alternatively, means may be provided to prevent the cover 22 from being returned to its position covering the keyhole 3 either permanently or temporarily. This provides a further visual indication of the cover's movement.

It will be appreciated that other variations and modifications may be made to this invention within the scope of this application.

Claims

1. A security lock comprising a lock mechanism which is normally in its locked condition, actuating means arranged, when enabled, to put the lock mechanism into its unlocked condition, and security means controlling the enablement of said actuating means, wherein said security lock further comprises override means for enabling said actuating means irrespective of the condition of said security means, and indicator means for indicating when the override means have been employed.

2. A security lock as claimed in Claim 1, wherein the override means enable unlocking of the lock even if the security means fails, whilst the indicator means show that the override means has been used.

3. A security lock as claimed in Claim 1 or Claim 2, wherein the override means comprises a key engageable within a keyhole provided in the security lock such that use of the key enables the actuating means.

4. A security lock as claimed in any preceding claim, wherein said indicator means comprises alarm means arranged to provide a visual or audible alarm signal upon use of the override means.

5. A security lock as claimed in any preceding claim, where the override means is a key, and wherein said indicator means comprises means arranged to be altered or moved by use of the key.

6. A security lock as claimed in any preceding claim, wherein detecting means are provided to detect or log any use of the override means.

7. A security lock as claimed in any preceding claim, wherein the override means comprises a key engageable within a keyhole in the lock, and the indicator means comprise a cover for the keyhole.

8. A security lock as claimed in any preceding claim, wherein said lock mechanism is mechanically operated, and wherein the actuating means is enabled mechanically by inputting a code into the lock.

9. A security lock as claimed in any preceding claim, wherein the security lock is electrically controlled, and the security means then comprises processor means and a user interface, actuation of the interface by a user being arranged to enable the actuating means.

10. A security lock substantially as hereinbefore described with reference to the accompanying drawings.