GB2516821A

GB2516821A - Lift door release arrangement

Info

Publication number: GB2516821A
Application number: GB1311991.2A
Authority: GB
Inventors: Raymond Ashby
Original assignee: Pawle & Co Ltd
Current assignee: Pawle & Co Ltd
Priority date: 2013-07-04
Filing date: 2013-07-04
Publication date: 2015-02-11
Anticipated expiration: 2033-07-04
Also published as: GB2516821B; GB201311991D0

Abstract

A lift door release arrangement comprises a locking device 10, a release bar 11 and a master key 20. The locking device 10 has a tubular housing 12, an inner axial keyway 13, and an outer axial keyway 14 surrounding the inner axial keyway 13. The inner axial keyway 13 is of triangular cross-section, preferably a triangle having flattened or rounded apexes. The outer axial keyway 14 has a lug 15 formed adjacent each apex of the inner axial keyway 13. The release bar 11 is arranged so as to engage upon deactivation of the locking device 10. The master key 20 has a triangular cross-section adapted to engage with the inner axial keyway 13, and has at its distal end a slot 24 formed in each triangular face 23 adapted to engage with a lug 15 of the outer axial keyway 14. Engagement of the master key 20 with the outer axial keyway 14 is required in order to deactivate the locking device 10. Further independent claims relate to the master key 20, preferably having individual identification means which may comprise a bar code, micro-chip or serial number, and the locking device 10 alone.

Description

Lift Door Release Arrangement This invention relates to a lift door release arrangement. In particular, it relates to a lift door release arrangement comprising a tubular locking device and an associated master key. The term "door release arrangement" is used herein to refer to the combination of a locking device and its associated key.

The use of door release arrangements in lift (elevator) doors has become commonplace as a safety feature. The main controls which enable the automatic opening and closing of doors during normal use are electronically operated. As such there is an inherent risk of passengers become trapped within the lift car if there is a power failure or a mechanical malfunction which requires electrical power to be shut off. Access to the interior of a lift car may also be desirable at other times when electrical power is not available, such as during installation or maintenance of the lift system.

As a consequence, it has become customary to fit lift doors with release arrangements comprising a tubular locking device in communication with a release bar arranged to engage with the lift's main, or an auxiliary, door opening mechanism. During normal operation of the lift the locking device will be in its locked condition, in which the release bar is not engaged. When manual opening of the doors is required -for example by a fire crew seeking to rescue trapped passengers during a power failure -a key is engaged with the locking device to change it to its unlocked condition (referred to hereinafter as "deactivating" the locking device). This engages the release bar, causing it to rotate and so in turn to engage the lift's door opening, or release, mechanism.

Depending on the particular design of lift this may either cause opening of the doors, or simply release a door brake mechanism, thereby to allow manual opening of the doors.

Depending on the particular design of lift, the door release arrangement may be fitted in the lift car door, the lift landing door, or both.

One popular design of lift door release arrangement whose use has become standard is known as a "Eurolock". This comprises a tubular locking device having a generally triangular keyway, adapted to receive a Eurolock key, having a triangular cross-section. Despite its widespread use, the Eurolock suffers from a shortcoming from a security point of view. As well as being operable by a triangular Eurolock key -such as would be in the possession of the emergency services, and security and maintenance personnel -the locking device can also be deactivated by using a standard key of triangular cross-section, such as those intended for use in connection with certain designs of gas cylinder, and other utilities. Such keys are widely available at hardware stores and the like, and so this leaves lifts fitted with Eurolocks vulnerable to unauthorised access, with the inherent risk of vandalism and unauthorised access to the building serviced by the lift.

In addition, the unauthorised accessing of lifts and lift shafts poses significant danger to the person obtaining such access, and there have been reports of serious injuries and deaths occurring as a result of such unauthorised access.

The present invention seeks to address the above issues by providing an improved Eurolock-type lift door release arrangement in which the keyway of the locking device is modified so as to prevent operation using widely available keys of simple triangular cross-section, and in which the associated key is provided with traceable identification means to enable the distribution of each said key to be regulated and monitored.

According to a first embodiment of the present invention there is provided a lift door release arrangement comprising: -a locking device having a tubular housing, an inner axial keyway of generally triangular cross-section formed in said housing, and an outer axial keyway surrounding said inner axial keyway and having a lug formed adjacent each apex of said generally triangular inner axial keyway; -a release bar arranged so as to engage upon deactivation of said locking device; and -a master key having a generally triangular cross-section adapted to engage with said inner axial keyway, and having at its distal end a slot formed in each said triangular face, wherein each said slot is adapted to engage with a lug of said outer axial keyway; and wherein engagement of said master key with said outer axial keyway is required in order to deactivate the locking device and so engage the release bar.

Aside from the modified keyway, the preferred locking device is essentially a conventional tubular lock, the operation and construction of which will be widely understood, and so will not be described herein in detail.

Preferably, engagement of the master key with both the inner and outer axial keyways is required in order to deactivate the locking device.

The shape of cross-section of the inner axial keyway is preferably that of a triangle having flattened or rounded apexes, with the cross-sectional shape of the master key being adapted accordingly.

When the locking device is mounted in a lift door, whether a lift car door or a lift landing door, the release bar is arranged upon engagement to rotate and thereby to engage with the lift system's main or auxiliary release mechanism thereby to cause or permit opening of the lift door.

According to a second embodiment of the present invention there is provided a locking device for a lift door release arrangement as hereinbefore described, said locking device comprising: a tubular housing, an inner axial keyway of generally triangular cross-section formed in said housing, and an outer axial keyway surrounding said inner axial keyway and having a lug formed adjacent each apex of said generally triangular inner axial keyway; and a release bar arranged so as to engage upon deactivation of said locking device.

According to a third embodiment of the present invention there is provided a master key for a lift door release arrangement as hereinbefore described, said master key having a generally triangular cross-section adapted to engage with said inner axial keyway, and having at its distal end a slot formed in each said triangular face, wherein each said slot is adapted to engage with a lug of said outer axial keyway.

The master key preferably further comprises individual identification means to enable the distribution of each said key to be monitored. The individual identification means may be, for example, a bar code, microchip, or other electronic tagging means capable of identifying an individual key.

Preferably however the individual identification means is a serial number applied to each individual key. Each individual key can thus be logged and monitored via a central register to ensure that only authorised persons -such as the emergency services, security and maintenance personnel -have access to the keys.

In order that the present invention may be more clearly understood, preferred embodiments thereof will now be described in detail, though only by way of example, with reference to the accompanying drawings, in which: Figure 1 shows a front view of a locking device and release bar assembly, forming a first part of a lift door release arrangement according to a preferred embodiment of the present invention; Figure 2 shows a side view of the locking device and release bar assembly of Figure 1; Figure 3 shows side and end views of a master key forming a second part of a lift door release arrangement according to a preferred embodiment of the present invention; and Figure 4 shows a side, cross-sectional view of the locking device and release bar assembly of Figures 1 and 2.

Referring first to Figure 1, there is shown a locking device 10 and release bar 11 assembly, forming a first part of a lift door release arrangement according to the present invention. The locking device 10 has a tubular housing 12. Aside from the modifications as herein described, the internal components of the locking device 10 (not shown in Figure 1) are constructed and operate essentially as per a conventional tubular lock.

An inner axial keyway 13 having a generally triangular cross-section, is formed in the housing 12. An outer axial keyway 14 is provided around the inner keyway 13, said outer axial keyway 14 having a lug 15 formed adjacent each apex of the generally triangular inner keyway 13.

Referring now to Figure 2, this shows a side view of the locking device of Figure 1, from which can be seen the form of the tubular housing 12, which is adapted to be mounted within a lift door panel (not shown). The distal end of the tubular housing 12 is provided with a locking ring 16, which can be adjusted to enable the locking device 10 to be mounted in doors of varying thickness. At the rear of the locking device 10 is mounted the release bar 11, which is arranged to engage with the lift's main or auxiliary door opening system upon deactivation of the locking device 10.

Referring now to Figure 3, there is shown a master key 20 forming a second part of a lift door release arrangement according to the present invention. The master key has a handle 21 and a shaft 22, the latter having a generally triangular cross-section complementary to that of the inner axial keyway 13 of the locking device 10, as can be seen by the end view detail X-X in Figure 3. Each face 23 of the triangular shaft 22 has formed therein a slot 24 having a width of substantially 5mm and a length of substantially 5.5mm, each said slot being adapted to receive a lug 15 of the outer axial keyway of the locking device 10. Each individual key 20 is marked with an individual serial number (not shown) such that the distribution of the keys 20 can be monitored via a key registration system.

Referring now to Figure 4, this again shows the locking device 10, though now in cross-sectional view in order to show certain internal components of the locking device 10, in particular the centre bar 17 by means of which the release bar 11 is mounted on the locking device 10, the compression spring 18.

In use, during normal operation of a lift, the locking device 10 will be in its locked condition with the spring 18 held under compression, and the release bar 11 prevented from moving and so engaging the lift's door opening system.

However, when the locking device 10 is deactivated by engaging the master key 20 therewith, the compression in the spring is 18 released. This in turn causes the centre bar 17 to drive the release bar 11 to rotate through substantially 45°, to engage the lift's door opening system.

Deactivation of the locking device 10 will only occur if both the triangular cross-sectional shaft 22 of the master key 20 is engaged with the inner axial keyway 13 of the locking device 10, and the slots 24 on the shaft 22 are engaged with the lugs 15 of the outer axial keyway 14. The locking device 10 can thus not be deactivated by a conventional triangular key.

Claims

Claims 1. A lift door release arrangement comprising: -a locking device having a tubular housing, an inner axial keyway of generally triangular cross-section formed in said housing, and an outer axial keyway surrounding said inner axial keyway and having a lug formed adjacent each apex of said generally triangular inner axial keyway; -a release bar arranged so as to engage upon deactivation of said locking device; and -a master key having a generally triangular cross-section adapted to engage with said inner axial keyway, and having at its distal end a slot formed in each said triangular face, wherein each said slot is adapted to engage with a lug of said outer axial keyway; and wherein engagement of said master key with said outer axial keyway is required in order to deactivate the locking device and so engage the release bar.
2. A lift door release arrangement as claimed in claim 1, wherein engagement of the master key with both the inner and outer axial keyways is required in order to deactivate the locking device.
3. A lift door release arrangement as claimed in claim 1 or claim 2, wherein the shape of cross-section of the inner axial keyway is that of a triangle having flattened or rounded apexes, and wherein the master key is adapted accordingly.
4. A lift door release arrangement as claimed in any of the preceding claims, wherein in use the locking device is mounted in a lift door such that the release bar is arranged upon engagement to rotate and thereby to engage with an auxiliary release mechanism to permit manual opening of said lift door.
5. A lift door release arrangement as claimed in any of the preceding claims, adapted for mounting in a lift car door.
6. A lift door release arrangement as claimed in any of the preceding claims, adapted for mounting in a lift landing door.
7. A lift door release arrangement as claimed in claim 1 and substantially as hereinbefore described with reference to the accompanying drawings.
8. A locking device for a lift door release arrangement as claimed in any of the preceding claims, said locking device comprising: a tubular housing, an inner axial keyway of generally triangular cross-section formed in said housing, and an outer axial keyway surrounding said inner axial keyway and having a lug formed adjacent each apex of said generally triangular inner axial keyway; and a release bar arranged so as to engage upon deactivation of said locking device.
9. A locking device as claimed in claim 8 and substantially as hereinbefore described with reference to the accompanying drawings.
10. A master key for a lift door release arrangement as claimed in any of claims 1 to 7, said master key having a generally triangular cross-section adapted to engage with said inner axial keyway, and having at its distal end a slot formed in each said triangular face, wherein each said slot is adapted to engage with a lug of said outer axial keyway.
11. A master key as claimed in claim 10, further comprising individual identification means to enable the distribution of each said key to be monitored.
12. A master key as claimed in claim 11, wherein the individual identification means comprises a bar code or micro-chip.
13. A master key as claimed in claim 11, wherein the individual identification means is a marking of an individual serial number on each key.
14. A master key as claimed in claim 11 and substantially as hereinbefore described with reference to the accompanying drawings.