GB2247094A

GB2247094A - Vehicle anti-theft device

Info

Publication number: GB2247094A
Application number: GB9012504A
Authority: GB
Inventors: Ronald Allan Proctor
Original assignee: Individual
Current assignee: Individual
Priority date: 1990-06-05
Filing date: 1990-06-05
Publication date: 1992-02-19
Also published as: GB9012504D0

Abstract

An anti-theft device for protecting an enclosed space such as the interior of a passenger car or other vehicle 10, comprising smoke-generating means 26 adapted to be arranged in the enclosed space and provided with a sensor or other automatic triggering means 18, 22, 24 for triggering the generation of smoke within the enclosed space directly someone seeks to gain unauthorised entry into it. <IMAGE>

Description

Vehicle Anti-theft Device This invention relates to a vehicle anti-theft device.

Among the vehicle anti-theft devices which are available on the market, there are those where a sensor on the vehicle detects unauthorised entry into the vehicle and passes a signal to an alarm of some kind. Normally, the alarm is an audio device which emits a loud noise like that from a siren. Such an alarm system will deter most vehicle thieves but it is still possible for a thief to break into a vehicle - for example by forcing open or breaking a window - and to make a quick get-away before anyone may respond to the audio alarm.

The aim of the present invention therefore is to provide a vehicle anti-theft device which also stops a thief from grabbing hold of any article within the vehicle.

This aim is achieved by means of a vehicle antitheft device which causes the vehicle interior to be filled with smoke or gas directly someone seeks to gain unauthorised entry into the vehicle.

An ideal gas for the purpose of the invention is carbon dioxide which is frequently used in theatres and places of entertainment generally to generate a smoke effect. Thus, the anti-theft device in accordance with the invention can comprise a container for carbon dioxide and means for releasing it into the interior of the vehicle on receiving a signal from one or more sensors on the vehicle which are adapted to detect attempted unauthorised entry into the vehicle.

The construction of the sensor is not critical from the point of view of the invention in that most if not all of those commercially available for use in vehicles can be used to produce the necessary signal in order for the gas or smoke to be released into the vehicle. The sensor may therefore be one which is heat-sensitive in that it detects the body heat of the thief as he or she enters the vehicle.

Alternatively, the sensor could be one which is sensitive to a change of air pressure such as occurs when entrance is gained to a vehicle. Vibration-sensitive, voltagesensitive or electric-current sensitive sensors could also be used.

There are other gases or "smokes" which can be used in place of carbon dioxide but it is important that they should not be so dangerous as to harm or injure the thief as that could result in a claim for damages against the vehicle owner. It might therefore be appropriate for a gas such as nitrous oxide (as used by many dentists) to be the gas provided in the container of the device, and another possibility might be tear-gas as used by police forces. On the other hand, it would not be appropriate to use a dangerous gas such as chlorine or hydrogen sulphide. On the whole, it is preferred that the gas used should be one which is released in the form of a dense smoke so that it is clearly visible and frightens the thief as well as preventing him or her from seeing the article or articles which he or she wants to steal.The smoke should also last for several minutes to ensure insufficient visibility for the vehicle to be driven.

The anti-theft device can be put into an "on guard" mode using control means which can be remotely-operated, for example by radio, infra-red or similar signaltransmitting equipment. As with other anti-theft devices, less expensive versions can also be provided which are put "on guard" by time delays on leaving the vehicle and time delays to allow for resetting on vehicle entry.

In order that the invention may be thoroughly understood, a specific example of a vehicle anti-theft device in accordance with it will now be described with reference to the accompanying drawing which shows a vehicle in diagrammatic plan view.

The vehicle is a typical passenger car having a body 10, four road wheels 12, seats 14 and a steering wheel 16. A voltage-sensitive sensor 18 is located near the driver's door 20 and is one of several adapted to be set off by a voltage drop. Another sensor 22 is located centrally of the vehicle, this one being arranged to be set off by vibration. A further sensor 24 is arranged near the rear of the vehicle body 10 and is a heat-sensing or infrared sensor.

All the sensors are electrically connected to a main unit 26 containing a receiver for messages from the sensors and also from radio and/or infra-red transmitting means (not shown) by which the anti-theft device is put into an "on guard" mode. The main unit 10 also includes time delay means and a gas canister and detonator.

Once therefore the main unit 26 has been put into an "on guard" mode by a message or signal transmitted to its receiver, any attempted break-in into the vehicle will be sensed by one or other of the sensors 18, 22 or 24 which will cause a message or signal to be sent by the thusinitiated sensor to the receiver of the main unit 26.

This will immediately result in operation of the detonator so that gas is released by the gas canister into the interior of the vehicle body 10.

Claims

1. An anti-theft device for protecting an enclosed space such as the interior of a passenger car or other vehicle, comprising smoke-generating means adapted to be arranged in the enclosed space and provided with a sensor or other automatic triggering means for triggering the generation of smoke within the enclosed space directly someone seeks to gain unauthorised entry into it.

2. An anti-theft device according to claim 1, in which the smoke-generating means comprise a container which contains material(s) for generating non-toxic smoke on being actuated electrically.

3. An anti-theft device according to claim 1 or claim 2, in which the smoke-generating means comprise ciruitry for receiving a message from the sensor and also from radio and/or infra-red transmitting means by which the anti-theft device can be put into and out of an "on guard" mode.

4. An anti-theft device according to any preceding claim, in which the smoke generating means include time delay means.

5. An anti-theft device according to any preceding claim, in which the smoke-generating means include a detonator adapted to be actuated electrically.

6. An anti-theft device according to any preceding claim, in which the smoke-generating means include an electrical lead for connection to a source of electrical power in or near the enclosed space.

7. An anti-theft device according to claim 6 for use in a vehicle, in which the electrical lead is adapted to be connected to an electrically-powered cigarette or cigar lighter forming part of the vehicle.

8. An anti-theft device according to any preceding claim, in which the sensor is heat sensitive so as to detect the body heat of a thief as he or she attempts to enter the enclosed space.

9. An anti-theft device according to any one of claim 1 - 7, in which the sensor is adapted to detect a change of air pressure which occurs when unauthorised entry is gained to the enclosed space.

10. An anti-theft device according to any one of claims 1 - 7, in which the sensor is able to detect vibrations.

11. An anti-theft device according to any one of claims 1 - 7, in which the sensor is able to detect changes in voltage or changes in electrical current.

12. An anti-theft device according to claim 1 substantially as described herein with reference to the accompanying drawing.

13. A road vehicle incorporating an anti-theft device as claimed in any preceding claim.

14. A vehicle according to claim 13, in which the smoke-generating means of the anti-theft device are fitted to a fixed part of the vehicle in its interior, there being at least one sensor mounted on the vehicle body to detect unauthorised entry into it.

15. A vehicle according to claim 13 or claim 14 having more than one sensor, in which one sensor is located near a door of the vehicle, another is located centrally of its body, and a third is arranged near the rear of the vehicle body.

16. A vehicle according to claim 13 substantially as described herein with reference to the accompanying drawing.