GB2347540A

GB2347540A - An alarm system

Info

Publication number: GB2347540A
Application number: GB9904682A
Authority: GB
Inventors: Lea Ziff; Paul Ziff
Original assignee: Individual
Current assignee: Individual
Priority date: 1999-03-01
Filing date: 1999-03-01
Publication date: 2000-09-06
Anticipated expiration: 2019-03-01
Also published as: GB2347540B; GB9904682D0

Abstract

An alarm system for a plurality of separated zones (3,4,5,6,7) each of which has at least one detector (8). The detectors 8 are rendered active or inactive selectively by a control system. The control system includes control means which are adapted to be carried by a person or are indicative of a person. When the alarm system is activated, the control means renders inactive the, or each, detector (8) in the zone in which the person is present, the remaining detector (8) of the system in the other zones remaining activated.

Description

An Alarm System This invention relates to an alarm system, particularly but not exclusively, for protecting domestic houses against unauthorised access.

Known alarm systems for such premises typically have a presence detector or similar device to indicate unauthorised activity. Apart from presence detectors, conventional alarm systems include door opening sensors, vibration sensors and/or glass breakage detectors which respond to certain frequencies of sound. In the conventional systems, all the detectors of the system are rendered active or inactive simultaneously by switching on or off a main control. Thus, the alarm can only be set by the last person leaving the house and unset by the first person entering the house.

The known systems have the disadvantage that the whole system is activated or deactivated simultaneously with the result that if any one is in the house the alarm has to be deactivated. The situation can therefore arise that unauthorised access to the house can be made whilst the occupants of the house are in one room. For example, burglars can break into a house while the occupants are asleep in a bedroom, or even in a downstairs room watching television. They would simply not hear the slight noise made by an intruder over the sound of the television.

The present invention seeks to provide an alarm system which overcomes this disadvantage of the known systems.

According to the present invention there is provided an alarm system for a plurality of separated zones, each of which has at least one detector, the detectors being rendered active or inactive selectively by a control system, the control system including control means adapted to be carried by a person, which control means, when the alarm system is activated, renders inactive the, or each, detector in a zone in which the person is present, the remaining detectors of the system in the other zones remaining activated.

The detectors may comprise any type of security device such as an infra-red presence detector, vibration sensor, pressure sensor, or audio responsive detector such as a glass breakage detector. Each zone, which may be a room in a house, may have one or more types of such detector.

Preferably, the means is automatic so that as a person moves through the zones, the detector (s) are automatically rendered inactive as the person enters a zone and rendered active again as the person leaves a zone.

The control means may be a coded transponder which may have built-in re-coding means to initiate a different control signal on each operation so that the detectors are given a signal of the type they are to respond to next time they are activated. In this way, it would be extremely difficult for burglars to detect and analyse the code from outside the building to deactivate the alarm themselves.

Basic forms of such signals are known from, for example, vehicle immobilising keys. The transponder may be incorporated in a wrist band or a necklace for example. The control means may have an additional function to selectively hold deactivated selected zones, possibly for a limited period of time. In this way, it would be possible for a person wearing a transponder to go and deactivate a kitchen for example, to enable other people to pass freely between, for example, a lounge and the kitchen.

It is envisaged that the control means may be responsive to characteristics of authorised personnel only, for example, to the iris of the eye or the hand print. When being set up, the system would be programmed to respond only to people previously entered on the system as being approved. The control means could have detectors at the door to each room which would be activated by the person's iris, or hand being placed on a detection plate positioned on or near the door.

It is also envisaged that the system may be adapted for use in commercial premises such as offices or factories to assist a security guard patrolling the premises. The control system, transponder and/or the detectors in the separate zones may have, additionally, means to record activation/deactivation activity. In this way it will be possible to monitor the activity of a security guard to ensure that he or she carries out security patrols in accordance with instructions.

A preferred embodiment of the present invention will now be described by way of example with reference to the accompanying informal drawing which shows a schematic plan view of a domestic house.

The house has a front door 1 and a back door 2 both having opening/closing detectors, which give access to a hall 3. A main control box 3a for an alarm system is located immediately behind the front door. The hall may have, additionally, a presence detector (not shown). The house has four rooms 4,5,6 and 7 in each of which there is a presence detector 8 which, when activated, responds to the presence of a person in the room to trigger the alarm system. When triggered, the alarm system will sound an audible warning, flashing lights and/or a signal to the police or security service in the conventional way.

The control system of the alarm system incorporates a portable transponder which is adapted to render inactive the or each detector in the hall or one of the rooms in which the person carrying the transponder is present. Thus, a person entering the house with the transponder need not switch off the alarm system since their presence in the hall when they enter the house will cause the deactivation of all the presence detectors and door closing/opening detectors which are present within the range of the transponder.

As the person leaves the hall, the detectors in the hall will automatically be reactivated and the detector or detectors in the room the person enters will automatically be deactivated as they enter the room. The person can thus move freely through the house without setting off the alarm, secure in the knowledge that all the other rooms are always activated to be responsive to unauthorised intrudal activity.

As mentioned earlier, the control signal emitted by the transponder is coded to make it difficult for burglars outside the house to detector and analyse the signal thus preventing them emulating the control signal of the transponder.

The system thus provides security and comfort to an occupant of a house since they can be confident that if they are in a bedroom, or in a lounge watching television, the alarm system in the rest of the house is still fully activated.

Claims

Claims 1. An alarm system for a plurality of separated zones, each of which has at least one detector, the detectors being rendered active or inactive selectively by a control system, the control system including control means adapted to be carried by or indicative of a person, which control means, when the alarm system is activated, renders inactive the, or each, detector in a zone in which the person is present, the remaining detectors of the system in the other zones remaining activated.
2. An alarm system according to claim 1, wherein the detectors are infra-red presence detectors or vibration sensors or pressure sensors or audio responsive detectors.
3. An alarm system according to claim 2, wherein when the detectors are audio responsive detectors, they are glass breakage detectors.
4. An alarm system according to claim 1, wherein each zone has more than one type of detector.
5. An alarm system according to any one of the preceding claims, wherein the control means is automatic, so that as a person moves through the zones, the detector (s) are automatically rendered inactive as the person enters a zone and rendered active again as the person leaves a zone.
6. An alarm system according to any one of the preceding claims, wherein the control means is a coded transponder which has built-in re-coding means to initiate a different control signal on each operation so that the detector (s) are given a signal of the type they are to respond to next time they are activated.
7. An alarm system according to any one of the preceding claims, wherein the control means is adapted to selectively hold selected zones inactive.
8. An alarm system according to claim 7, wherein the selected zones are held inactive for a limited period of time.
9. An alarm system according to any one of the preceding claims, wherein the control means is incorporated in a wristband or necklace.
10. An alarm system according to any one of claims 1-8, wherein the control means is responsive to a characteristic or characteristics o f an authorised person.
11. An alarm system according to claim 10, wherein the control means is responsive to the iris of the eye or the hand print of the authorised person.
12. An alarm system according to any one of the preceding claims, wherein means are provided to record the activation/deactivation activity of the alarm system.
13. An alarm system according to any one of the preceding claims, wherein at least one zone is a room in a house.
14. An alarm system substantially as described herein with reference to and as illustrated in the accompanying drawings.