EP0382412A2

EP0382412A2 - Locking system

Info

Publication number: EP0382412A2
Application number: EP90301075A
Authority: EP
Inventors: Michael Wong Siu On; Kin Shing Yeung; Simon Wong Kwok Keung
Original assignee: Citic Industries Ltd
Current assignee: Citic Industries Ltd
Priority date: 1989-02-09
Filing date: 1990-02-01
Publication date: 1990-08-16
Also published as: EP0382412A3; GB8902951D0

Abstract

A door locking system which consists of a mechanical locking mechanism (10), such as a dead-bolt (13), releasable by an electrical operating means (26), such as a solenoid, controlled by an electronic control system (11) provided with means (27) for receiving coded information from a card (28), means (31) for decoding the coded information, a master control module (12), and a by-pass override system (35, 37, 38) for receiving coded information for overriding the information receiving and decoding means (27, 31).

Description

This invention relates to a locking system of the kind in which a mechanical locking mechanism can be operated by an electrical operating system controlled by an electronic control system provided with means for receiving coded information and means for decoding the coded information, or by mechanical means.
There are many different types of known electronically controlled locking devices which utilise coded information in order to effect release of the locking mechanism, such coded information being supplied by a manually operated touch-pad or push-button system and/or a card bearing coded information.
A disadvantage of the known electronically controlled locking devices is that if the electronic control system suffers a malfunction, or if the entry code is forgotten, or if the card bearing coded information is lost or damaged, it is necessary to utilise a mechanical key in order to release the mechanical locking mechanism. The provision of a mechanical key creates an inconvenience in that the key must be kept in a safe accessible place at all times so that access to it can be had if the electronic control system fails for any reason. Such a key must either be carried by a person at all times or left in a safe place in a remote establishment. This is highly inconvenient.
The major factors affecting malfunctioning of known locking systems are the failure of individual electronic components and the electrical operating system. Other failures causing malfunctions that make normal unlocking impossible are power failure, a defective rectifier which rectifies the mains electrical power source, voltage reduction of the stand-by battery, loss of electronic memory, open/short circuiting of the operating solenoid, card decoder circuit failure etc.
Other factors making unlocking impossible are magnetic corruption on the card, loss of or damage to a card and forgotten entry code.
According to the present invention there is provided a locking system comprising a mechanical locking mechanism releasable by an electrical operating means controlled by an electronic control system which includes means for receiving coded information, means for decoding the coded information, a master control module, and a by-pass override system for receiving coded information for overriding the information receiving and decoding means.
Preferably the by-pass override system comprises a decoder for receiving signals from a key-pad forming part of the means for receiving coded information and which is used for the input of coded by-pass information, said decoder being electrically connected to a comparator.
The override system preferably also includes a by-pass code encoder.
The mechanical locking mechanism preferably comprises a dead-bolt, resilient means for urging the dead-bolt to its inoperative position, a latch mechanism for latching the dead-bolt in its operative position, and said electrical operating means comprises an electrical solenoid for operating the latch mechanism to release the dead-bolt.
An embodiment of the invention will now be described, by way of an example, with reference to the accompanying drawings, in which:-

Figure 1 is a diagrammatic perspective view of the mechanical locking mechanism of the locking system and the electrical operating system;
Figure 2 is a diagrammatic perspective view of the edge portion of a door provided with the locking system;
Figure 3 is a diagrammatic circuit diagram of the electronic control system: and
Figure 4 is a block diagram of the stages of operation of the electronic control system.

The locking system comprises three basic units which comprise an electrically actuated mechanical locking mechanism 10, an access control unit 11, a master control module 12 and a power source.
The electrically actuated mechanical locking mechanism 10 is shown in Figures 1 and 2 and consists of a dead-bolt 13 which when in the engaged or locked position acts as a shear pin and it is moved to the engaged or locked position by a rotatable thumb-turn 15 mounted on the door 16 or alternatively on the door frame (not shown) depending upon whether the casing 14 is mounted on the door 16 as shown in Figure 2 or on the door frame. The thumb-turn 15 is provided on a spindle 17 having at its other end an arm 18 which engages against a pin 19 which is connected to and extends transversely of the dead-bolt 13. The pin 19 extends through a longitudinally extending slot 20 provided in the casing 14. The rear end of the dead-bolt 13 is connected to a tension spring 21. In the region of its forward end the dead-bolt 13 is provided with a peripheral groove 22 in which can engage an arm portion 23 of a rotatable latch 24. The latch 24 is connected to a tension spring 25 which urges the arm portion 23 in a direction towards the dead-bolt 13. The arm portion 23 is connected to an electrical solenoid 26 which constitutes the electrical operating system of the locking mechanism and which is energised in response to the "open" command signal from the electronic control system later described.
The dead-bolt 13 may be hollow, or partly hollow, and the tension spring 21 can be located within the hollow dead-bolt 13 so as to form a compact unit.
When the thumb-turn 15 is rotated anti-clockwise as viewed in Figure 1, the arm 18 engages the pin 19 and moves the dead-bolt 13 towards the locking position against the force of the spring 21 which is thus tensioned. During this movement the arm portion 23 of the latch 24 rides on the peripheral surface of the dead-bolt 13 and when the dead-bolt 13 is in the locked position the arm portion 23 engages in the peripheral groove 22 and is retained therein by the tension spring 25. The arm portion 23 when engaged in the groove 22 prevents the dead-bolt 13 being withdrawn. In this position rotation of the thumb-turn 15 will not move the dead-bolt 13.
When the solenoid 26 is energised in response to the "open" command signal from the electronic control system the arm portion 23 is moved against the force of the spring 25, thus tensioning the spring 25, and is disengaged from the groove 22. The dead-bolt 13 is then moved to the unlocked position by the tension spring 21.
In order to unlock the door from the inside this can be achieved by having a mechanical linkage connected to the mechanical locking mechanism 10 to override the electronic locking system or alternatively an electrical switch can be provided inside the premises to energise the solenoid 26 direct.
The solenoid 26 is controlled by an electronic control system as shown in Figure 3. This system comprises a card reader 27 for reading coded information provided on a card 28. The card 28 has a matrix pattern 29 with the matrix being formed of a material different to that of which the card 28 is formed. The card reader 27 has a plurality of Hall effect elements 30 arranged in the same pattern as the matrix pattern 29. The card reader 27 is in connection with a card decoder 31 which comprises a wiring arrangement 32 corresponding to a specific code pattern and logic circuitry 33 for decoding. The card reader 27 is connected to a central controller 34 which comprises a series of logic gates and which has an output for conveying a signal to the solenoid 26. The central controller 34 is housed at a remote location within the building.
The electronic control system is also provided with a by-pass code override system for overriding the card reader 27 and card decoder 31. The by-pass system comprises a key-pad 35 having twelve push-button or touch-pads 36. Ten of the push-button or touch-pads 36 are assigned for numbers 0 to 9 and two of them are assigned for function, such as "programme" and "enter". The key-pad 35 is connected to a key decoder 37 which consists of a 10 to 4 line priority encoder and a 16 bits register. The key decoder 37 is connected to a comparator 38 which consists of two 8-bit magnitude comparators and the comparator 38 is connected with the central controller 34 and with a by-pass code encoder 39 which is made up of four 4-bit rotary switches 40.
The card reader 27 and key-pad 35 will be located on the outside of the premises. Access to the premises can normally be made by simply entering the card 28 in the card reader 27 followed by entering a four digit entry code via the key-pad 35. The entry code can be user programmable by means of the key-pad 35. Change of entry code can only be effected with a valid card 28 and a valid by-pass code entry.
One of the main features of this system is the capability of being able to use a by-pass code to override the card encoding system. This facility is particularly useful in the case when the person who wants to gain entry has lost or damaged his or her card 28. The person has the option to use the by-pass code together with the four digit entry code to gain access.
Also, if the card reader 27 fails for any reason, the person can adopt this procedure to gain entry.
The by-pass code can be user programmable and stored in the central controller.
It is possible for the main electrical supply to fail and for a voltage reduction in the stand-by battery to occur simultaneously. To prevent users from being unable to unlock the door if such failures take place the system is provided with the facility to be able to connect an external power source to the system through a connector (not shown) so that the system can be energised. The external power source connector will include means for preventing short circuiting of the system during normal operation of the system. In order to cater for the remote possibility of failure of the solenoid 26 due to open or short circuiting, or failure of the micro-computer in the central controller 34, a switch is provided for selecting the working channel.
The central controller 34 accommodates duel channel control circuitry and a set of DIP switches. A VLSI micro-processor and a solenoid energising circuit constitutes one channel and the other channel acts as a stand-by supporting circuit. The micro-processor interfaces and processes all the signals generated by the card reader 27, key-pad 35. Should a malfunction of any one of the components in the circuit occur the stand-by supporting channel can be selected in the access control unit to gain access.
The four digit by-pass code is user programmable by means of the DIP switches. There is no restriction on the number of changes which can be made of code selection.
Loss of entry code memory in the micro-processor can happen but is unlikely due to the stand-by battery. However, if the entry code is lost, access can be made with a valid card 28 and a valid by-pass code entry.
The electrical operating system can comprise two solenoids 26, one of which is used as a stand-by solenoid. Selecting one or the other solenoid can be effected through a switch provided on the central controller 34.
The door 16 can be provided with a conventional door handle 41 to operate a conventional latch-bolt 42 and with an auxiliary latch-bolt 43.
The stand-by battery preferably comprises a rechargeable battery which is constantly charged by a charging circuit.

Claims

1. A locking system comprising a mechanical locking mechanism (10) releasable by an electrical operating means (26) controlled by an electronic control system (11) which includes means (27) for receiving coded information, means (31) for decoding the coded information, a master control module (12), and a by-pass override system (35, 37, 38) for receiving coded information for overriding the information receiving and decoding means (27, 31).

2. A locking system as claimed in claim 1, in which the by-pass override system (35, 37, 38) comprises a decoder (37) for receiving signals from a key-pad (35) forming part of the means for receiving coded information and which is used for the input of coded by-pass information, said decoder (37) being electrically connected to a comparator (38).

3. A locking system as claimed in claim 1 or claim 2, in which the by-pass override system includes a by-pass code encoder (39).

4. A locking system as claimed in any preceding claim, in which the electronic control system (11) also includes a card reader (27) for reading a card (28) provided with a matrix pattern (29) forming coded information, said card reader (27) having a plurality of Hall effect elements (30) arranged in the same pattern as the matrix pattern (29), said means (31) comprising a card decoder provided with a logic circuit (33) and connected to a central controller (34) whose output is supplied to the electrical operating means (26).

5. A locking system as claimed in any preceding claim, in which the mechanical locking mechanism (10) comprises a dead-bolt (13), resilient means (21) for urging the dead-bolt (13) to its inoperative position, a latch mechanism (23, 24, 25) for latching the dead-bolt (13) in its operative position, and said electrical operating means comprises an electrical solenoid (26) for operating the latch mechanism (23, 24, 25) to release the dead-bolt (13).

6. A locking system as claimed in claim 5, in which the dead-bolt (13) is moved to its locking position by a rotatable thumb-turn (15) provided on a spindle (17) having an arm (18) which engages a pin (19) connected to and extending transversely of the dead-bolt (13).

7. A locking system as claimed in claim 5 or claim 6, in which the dead-bolt (13) is provided with a peripheral groove (22) in which an arm portion (23) of the latch mechanism engages when the dead-bolt (13) is in its operative position.

8. A locking system as claimed in any one of claims 5 to 7, in which a further stand-by solenoid (26) is provided which can be selected by a switch provided in the central controller (34).

9. A locking system as claimed in any preceding claim, in which a mechanical linkage is connected to the locking mechanism (10) to override the electronic locking system to enable the mechanical locking mechanism (10) to be unlocked.

10. A locking system as claimed in any one of claims 1 to 8, in which an electrical switch is provided to energise the electrical operating means (26) to enable the mechanical locking mechanism (10) to be unlocked.