GB2398417A

GB2398417A - Personal property alarm system

Info

Publication number: GB2398417A
Application number: GB0303179A
Authority: GB
Inventors: John Williams
Original assignee: Individual
Current assignee: Individual
Priority date: 2003-02-12
Filing date: 2003-02-12
Publication date: 2004-08-18
Also published as: GB0303179D0

Abstract

A personal alarm device comprises a tag attached to the article being protected and a remote controller carried by the owner. The controller transmits short range coded infra red control signals, the range of which defines a personal security area. The tag includes an infra red receiver such that if the tag is located within the security area then it receives the control signals and keeps open a switch/relay to prevent an alarm from sounding. However, if the tag is moved outside of the security area, eg. by a thief such that the strength of the received signal falls below a predetermined threshold or the signal is lost, then the switch/relay closes and the tag sounds an audible alarm to draw attention to the perpetrator and to aid in the recovery of the stolen article. The remote controller may control a number of such security tags simultaneously. The invention addresses the loss or theft of personal property in crowded areas such as shops or railway stations where it is necessary for the actual item being protected to sound an alarm, thus identifying the perpetrator and leading to the immediate recovery of the stolen item.

Description

1 239841 7 An Alarm System The invention relates to the field of alarm

systems. More specifically, the present invention relates to a personal alarm system which aids in the protection and recovery of personal items of value.

There are many devices and systems that seek to protect personal items and warn of theft or loss. Such devices and systems are described in, for example, US5838234, GB 2375424, W002077938, GB2228814 and FR2608868.

Many of these systems seek to warn the owner that theft or loss has occurred without addressing the recovery of the article or, in the case of theft, the identification of the perpetrator. This is particularly relevant in crowded locations such as Railway Stations where merely knowing that theft has occurred can be unhelpful. An alarm sounding on the victim can assist the perpetrator to escape into the crowd by drawing attention to the victim rather than the culprit. In the case of Pickpockets, stolen items are often passed to a second or even third individual in an attempt to hinder identification of the thief or identify the location of the property concerned.

The device of GB2228814 not only alerts the owner that an item of personal property such as a wallet, handbag or purse has been removed, but by the sounding of an alarm on the actual property itself at close range, identifies the person concerned in the theft and to cause that person to discard the property within sight of the victim. Thus resulting in the immediate recovery of the stolen article.

It is known (e.g. in GB2228814) to operate a property alarm system comprising a radio wave transmitter and receiver, for sending coded radio control signals. However, there are some disadvantages to using radio signals in such a device. Radio interference may arise in certain environments, causing errors in signal detection by the receiver. For example, interference may occur if the device was used close to electrical equipment or electrical machinery. If the receiver cannot detect the signal from the transmitter, the alarm may sound, although no item has been stolen. Such false alarms are preferably to be avoided.

In addition, radio waves may propagate unpredictably, making it difficult to control the range over which the alarm system will operate.

Further, the alarm itself may adversely affect sensitive electronic equipment, for example, in a hospital.

The present invention addresses the above problems, and a first aspect provides an alarm system comprising a tag, said tag comprising a receiver for receiving an infra-red control signal, means for generating an alert signal, and means for activating said means for generating an alert signal if the signal strength of said control signal at the receiver is lower than a predetermined value.

Generally, infra-red radiation is regarded as being in the frequency range of 3 THz to 450 THz.

The means for generating an alert signal may comprise a sound generator. Preferably, the sound generator generates a loud, high frequency noise, so that it will attract attention in a crowd. The sound generator may be a siren.

The alarm system may further comprising a remote receiver. The means for generating an alert signal may comprise a transmitter for transmitting an alert signal to said remote receiver. The tag may comprise both a sound generator and a transmitter for transmitting an alert signal. Both the sound generator and the transmitter on the tag may be used to generate the alert.

Preferably, the tag comprises means for activating said means for generating an alert signal if said signal is not detected by said receiver. Preferably, the alarm unit further comprises a remote control unit with a transmitter for transmitting said infra-red control signal to the receiver.

The output power of said transmitter on the remote control unit and the sensitivity of said receiver on the tag may be configured in order to define a zone around the transmitter on the remote control unit such that no signal will be detected by the receiver on the tag when the receiver on the tag is outside said zone, and wherein a part of the zone boundary lies within a predetermined range of distances from the transmitter on the remote control unit. The power and said sensitivity are preferably selected such that said part of the zone boundary is between 1 metre and 4 metres from the transmitter, and yet more preferably, so that the zone boundary is 2 metres from the transmitter.

Preferably, the whole of the zone boundary is within the predetermined range of distances. Nearby objects, such as a metallic floor, may screen the transmitted signal and reduces the size of the zone in a particular direction. However, this will not affect the usefulness of the device to detect if the object is moved outside the zone.

Preferably, the signal is transmitted in an encoded format by the transmitter on the remote control unit, and the tag comprises means to decode the signal. The code may be unique to a particular remote control unit, and the tag may be configured to work only with that remote control unit.

The transmitter on the remote control unit may further comprise means for transmitting a second control signal for disabling said means for generating an alert signal, wherein the tag comprises means for disabling the means for generating an alert signal when said second control signal is received by said receiver on the tag.

A plurality of tags may be provided, each tag being configured to be controlled by said remote control unit. The alarm system may be configured to allow said remote control unit to disable all of said plurality of tags simultaneously. The alarm system may further comprise means for allowing said remote control unit to separately control one or more individual tags of said plurality of tags.

A second aspect of the present invention provides an alarm system comprising a first unit and a second unit, said first unit comprising an infra-red transmitter, and said second unit comprising an infra-red receiver for receiving a control signal from said transmitter, a means for generating an alert signal and means for activating said means for generating an alert signal if the signal strength of said signal at the receiver is lower than a predetermined value.

The second unit may be used to tag a valuable object, and the first unit may be carried by a person. Alternatively, the first unit may be used to tag a valuable object, and the second unit may be carried by a person. In this case, where the means for generating an alert signal is a sound generator, the sound generator will sound on the person, and not on the tag. The zone set-up, signal coding, and multiple tag control scheme of the first aspect of the invention may also be applied to the second aspect.

Preferably, the means for activating said means for generating an alert signal comprises an electronically controlled switch. For example, this may be a transistor or a relay.

Preferably the tag has a maximum size of 50mm by 80mm by 4mm. Preferably, the remote control unit also has a maximum size of 50mm by 80mm by 4mm.

The tags may comprise means for attaching to an object, for example, a clip, a key ring, a screw, a bolt, or a sticky pad. The tags may be attached to an object such as a purse or handbag.

To reduce or eliminate potential problems with infra-red absorption, additional means for detecting an infra-red signal may be provided. For example, a tag may be provided with an additional infra-red sensor, which is connected to the tag by signal conducting means, such as a wire, or an electrical or optical cable. The signal is detected by the additional infra-red sensor, and sent to the tag via the signal conducting means. The remote sensor may be positioned in a location in which a user expects it to receive a stronger infra-red signal from the transmitter. For example, the tag may be positioned inside an object such as a handbag or purse, and the remote sensor may be positioned on the outside of the object.

Alternatively, the infra-red receiver of the tag may be connected to the tag via signal conducting means such as a wire or cable. The receiver may then be positioned in a more accessible location for receiving infra red signals than the rest of the tag. For example, the rest of the tag may be positioned inside a handbag, but the receiver may be mounted on the outside of the handbag, with the signal conducting means relaying the received signal back to the rest of the tag.

Similarly, the transmitter of the remote control unit may be connected to the remote control unit via signal conducting means such as a cable or wire. This would allow a person to put the remote control unit in a location in which significant levels of infra-red absorption may occur, such as in a pocket, while positioning the transmitter in a more accessible location for receiving infra-red, for example, pinned to a lapel.

The remote control unit may be provided with a plurality of means for emitting an infra- red signal. A means for emitting an infra-red signal may be built into the housing of the remote control unit. Preferably, a means for emitting and infra-red control signal is connected to the remote control unit by a signal conducting means such as a flexible wire or cable.

The alarm system may take the form of a personal alarm control card and an alarm card.

Preferably, the personal alarm control card, carried by the user, will set up a personal security area by the transmission of a coded signal. The alarm card, preferably being approximately of credit card dimensions will be carried in or attached to the item being protected. Transmissions from the control card will be received by the alarm card causing a switch/relay to remain open whilst it receives the coded signal. On leaving the pre-determined personal security area, the alarm card loses the signal, the switch/relay closes and the alarm sounds. A separate coded signal from the control card is used to activate the alarm card prior to use. Multiple alarm cards may be controlled from the one control unit.

The size of the personal security area may be variable depending upon the protection sought. The activation switch may also be used to disable the alarm temporarily should the immediate sounding of the alarm present a danger to the user e.g. Robbery or Mugging. A personal security area may be set up to protect items of personal property left alone temporarily. The device may be used to warn that an item has been left behind e.g. a handbag left at the Supermarket Checkout.

The control unit may be fitted or not with a clip or attachment device to fit securely in a pocket or on a belt.

The transmitter and receiver communicate via an infra-red signal. Infra Red absorption is a potential source of difficulty for an infra-red controlled alarm system. However, these problems may be reduced or eliminated by providing additional IR sensor(s).

Infra Red has the following advantages over a radio frequency alarm unit. I An IR device can be used in areas where radio or similar would not work properly or was prohibited.

Low Power IR poses no health hazard.

Multi-channel from small select area to much larger if required.

À Envelope of reception is controllable and totally predictable.

Interference free signals even in areas of high electrical radiation and noise.

À IR Equipment emits effectively no electrical signals to effect sensitive electronic systems or unstable materials À No licence requirements À Secure & not effected by electromagnetic radiation from electronic/electrical equipment - Interference free The signals are well contained and practically impossible to detect at even moderate distances when compared to low power radio.

The alarm unit may use IR Digital encoding. The tag and the remote control unit may be provided with transceivers, and the system may operate using full duplex channels.

In a preferred form of the invention, the IR transmitter would be located on a person, and the receiver would be located on the tagged object. Alternatively, the transmitter may be located at a chosen location, such as in a person's bag, termed the main radiation point. However, a transmitter/receiver may be on both the object and the person or main radiation point to allow for additional flexibility of the system.

The remote control unit may be provided with vibration means, to allow it to give a warning 'vibration Alert' prior to the main alarm sounding on the object. This would give the user prior warning, to allow them to disable the alarm before it actually sounded. It would be useful in the case of forgetting a bag at the checkout. The vibration means may be controlled by a signal transmitted from the tag to the remote control unit. This signal may enable the vibration means, or may prevent it from activating.

It would be feasible to have the alarm sounding on the object being protected or on the person/radiation point depending on the requirements at the time.

It is envisaged that the transmitter could be placed in the vicinity of the protected object.

Where a bag is to be protected, the transmitter may be placed in a pocket on the side, or the transmitter may be placed on a belt. Infra-red can penetrate some clothing, some shopping bags, and some wallets. Additional sensors could be provided to act in a remote capacity. For example, an additional remote sensor could be clipped to the top of a bag. A wallet in a pocket could have an additional or remote sensor attached to the top of the fold spine, on the outside. The transmitter in a pocket, with an additional sensor on the lapel.

Instead of a siren, or in addition to a siren, the alarm unit may comprise means to generate a voice warning, such as 'Stop Thief'.

The IR emitter may use pulses rather than a steady emission to save battery life. A motion sensor may be incorporated to assist in this aspect. Additional or remote sensors can be provided to cover any difficulties with IR Absorption.

The effective range of this system may be set up to be within a fixed range (e.g. 1 Om) of the transmitter, or within a chosen area (e.g. 100 sq m) surrounding the transmitter. It would therefore be possible to adapt this system to cover a much larger area by the use of IR repeaters or IR Antennae. This may be a building block system with add on components allowing for the complete protection of personal and other property within a given area.

The alarm system may have a dual function as a personal attack alarm. The alarm may be capable of being activated by the user, e.g. if he or she is attacked on the street. An attention attracting noise may then be emitted, such as a loud siren. This may be the same siren as is used to alert the user if the tagged items are moved outside the control signal zone. The activation switch of the control card may be used to set off the alarm as a personal protection device.

The alarm system of the invention may be configured with a plurality of transmitters which are positioned at different locations, and a tag which receives infra-red signals from any of said plurality of transmitters. The tag may activate the means for generating an alert signal only if the signal strength of the signal transmitted by all of the plurality of transmitters is below a predetermined value. This may extend the range of the protected zone, outside which the alarm will be sounded.

In the case where the tag comprises a transmitter, the tag may be provided with means to transmit an alert signal, either when the alarm is sounded, or as an alternative to sounding the alarm. A remote receiver, or a plurality of remote receivers, may be provided for receiving the alert signal. The remote receiver or plurality of receivers may be networked or linked to a control point, e.g. a control room, where receipt of the alert signal is noted, allowing security or police to respond.

Where a plurality of receivers is in use, the alarm system may be used as a simple tracking device allowing security or police to be directed to the location of the tagged object.

An example of this is where a chain of receivers are set up, e.g. in a town centre. On activation of the alarm, the transceiver transmits a warning to the nearest receiver, which in turn passes it by infra-red, cable, radio or other means to the control room. The nearest receiver may be the only receiver at which the warning signal is detected or it may be the receiver at which the signal strength of the warning signal is strongest.

Each receiver would in turn be activated as the tag comes into range, thus giving an accurate location for the theft or incident. When the device is used as an attack alarm, it would be possible to provide the location in a similar way.

The transmitter on the tag may be an infra-red transmitter, or may be a different type of t transmitter such as a radio transmitter. It is preferably configured to transmit on a different channel from the channel on which the infra-red receiver of the tag is configured to operate.

A preferred embodiment of the invention will now be described by way of example only, with reference to the accompanying drawings in which: Figure I shows the Personal Security Area in a preferred embodiment of the invention, with both control & alarm cards contained within that area.

Figure 2 shows the alarm card outside of the personal security area.

Figure 3 shows the control card according to a preferred embodiment of the invention.

Figure 4 shows the alarm card according to the preferred embodiment.

Figure 5 shows the alarm card of figure 4, when activated and in standby mode.

Figure 6 shows the alarm card of figure 4, when activated and in alarm mode.

Figure 7 shows a further embodiment in which the tag has an additional infra red sensor and the remote control unit has an additional infra-red transmitting means.

Figure 8 shows an enlarged view of the handbag of figure 7.

Figure 9 shows a further embodiment, in which the tag is inside a wallet, and an additional sensor is provided at the top of the spine of the wallet.

Figure 10 shows a further embodiment, in which a tracking system is also implemented to monitor the location of the tag.

Figure 1 shows the Personal Security Area with both control & alarm cards contained within that area. No alarm is sounded. Figure 2 shows the alarm card outside of the personal security area, and this causes the alarm on the alarm unit to sound.

As shown in figure 3, the personal alarm control card comprises a battery pack I which powers the transmitter 2. An on/off switch 3 activates the unit and also the alarm card, this also allows for a test function. A standby switch 4 sends the signal to the alarm card opening the switch/relay and thus placing the alarm in standby mode.

As shown in figure 4, the alarm card unit comprises a battery pack 1, a receiver 5, switches/relays 6 & 7 and the alarm module 8.

Figure 5 shows the alarm card when activated and in standby mode. The switch/relay 9 is in active mode whilst 10 shows the alarm switch/relay in open or standby mode.

Figure 6 shows the alarm card, when activated and in alarm mode. 11 shows the alarm switch/relay closed and alarm 12 sounding.

The transmitter and receiver work within a preset range Figure 1. Once activated, the coded signal is transmitted to the receiver card and as long as the card is within the personal security area no alarm is sounded.

Should the alarm card leave the personal security area Figure 2, the alarm is immediately sounded on the protected item of property.

Figure 7 shows a person holding a handbag. The person has a remote control unit in a pocket of their clothing, and the remote control unit is fitted with additional means for transmitting an infra-red signal. This additional transmitting means is connected to the remote control unit by a flexible cable.

A tag is positioned inside a handbag, and the tag has an additional infrared sensor which is connected to the tag by a flexible cable. Figure 8 shows a more detailed view of the tag and the handbag. The additional infra-red sensor is positioned on the outside of the handbag. This avoids problems of infra-red absorption by the handbag.

Figure 9 shows a wallet into which a tag has been placed. The tag has an additional sensor which is connected by a flexible cable. The additional sensor is placed at the top of the spine of the wallet to avoid problems of infra-red absorption by the wallet.

Figure l O shows a further embodiment of the invention, in which a tracking system is also implemented to monitor the location of the tag 21. The tag 21 comprises a transmitter as well as an infra-red receiver. A plurality of external transceivers 22 are provided. Each of the external transceivers 22 may transmit a control signal to the tag 21. Each transceiver 22 may also receive a signal emitted by the transmitter on the tag 21. The approximate position of the tag may be determined according to the received signal strength at each of the external transceivers 22.

The external transceivers 22 are all linked to a control room 24, by links 23 such as electrical cables or radio links. In the control room 24, the approximate position of the tag may be estimated according to the received signal strength at each of the transceivers 22. This information may be recorded as a function of time. If the tagged object is stolen, the police or security services may be alerted, and given information on the location of the tagged object. This may lead to the recovery of the stolen item.

Claims

CLAIMS: 1. An alarm system comprising a tag, said tag comprising a

receiver for receiving an infra-red control signal, means for generating an alert signal, and means for activating said means for generating an alert signal if the signal strength of said control signal at the receiver is lower than a predetermined value.
2. An alarm system as claimed in claim 1, wherein said means for generating an alert signal comprises a sound generator.
3. An alarm system as claimed in claim 1, said alarm system further comprising a remote receiver, wherein said means for generating an alert signal comprises a transmitter for transmitting an alert signal to said remote receiver.
4. An alarm system as claimed in any one of the previous claims, wherein said tag comprises means for activating said means for generating an alert signal if said control signal is not detected by said receiver.
5. An alarm system as claimed in any one of the previous claims, wherein said tag has a maximum size of 50mm by 80mm by 4mm.
6. An alarm system as claimed in any one of the previous claims, wherein said means for activating said means for generating an alert signal comprises an electronically controlled switch.
7. An alarm system as claimed in any one of the previous claims, further comprising a remote control unit, said remote control unit comprising a transmitter for transmitting said infra-red control signal to said tag.
8. An alarm system as claimed in claim 7, wherein the output power of said transmitter on the remote control unit and the sensitivity of said receiver on the tag have been configured in order to define a zone around the transmitter such that no signal will be detected by the receiver on the tag when the receiver on the tag is outside said zone, and wherein a part of the zone boundary lies within a predetermined range of distances from the transmitter on the remote control unit.
9. An alarm system as claimed in claim 8, wherein said power and said sensitivity are selected such that said part of the zone boundary is between 1 metre and 4 metres from the transmitter on the remote control unit.
10. An alarm system as claimed in any one of claims 7 to 9, wherein said signal is transmitted in an encoded format by the transmitter on the remote control unit, and said tag comprises means to decode said signal.
11. An alarm system as claimed in any one of claims 7 to 10, wherein said control signal is a first control signal, wherein said transmitter on the remote control unit further comprises means for transmitting a second control signal for disabling; said means for generating an alert signal, and wherein said tag comprises means for disabling said means for generating an alert signal when said second control signal is received by said receiver on the tag.
12. An alarm system as claimed in any one of the previous claims, wherein a plurality of tags are provided, each tag being configured to be controlled by said remote control unit.
13. An alarm system as claimed in claim 12, configured to allow said remote control unit to disable all of said plurality of tags simultaneously.
14. An alarm system as claimed in claim 12 or claim 13, further comprising means for allowing said remote control unit to separately control one or more individual tags of said plurality of tags.
15. An alarm system as claimed in any one of the previous claims, said tag comprising a transmitter and said alarm system comprising a plurality of remote receivers for receiving a signal from the transmitter on the tag, wherein said alarm system is configured to monitor the position of the tag using the received signal strengths of said signal at said remote receivers.
16. A tag for use in the alarm system of any one of the previous claims.
17. A remote control unit for use in the alarm system of any one of claims 1 to 15.
18. An alarm system comprising a first unit and a second unit, said first unit comprising an infra-red transmitter, and said second unit comprising an infra-red receiver for receiving a control signal from said transmitter, a means for generating an alert signal and means for activating said means for generating an alert signal if the signal strength of said signal at the receiver is lower than a predetermined value.
19. An alarm system as substantially as described herein with reference to Figures 1 to of the accompanying drawings.