AU628605B2 - Anti-theft device for vehicles - Google Patents

Description

628605 LTH OF AUSTRALIA Act 1952-1969 Form COMPLETE SPECIFICATION

(ORIGINAL)

FOR OFFICE USE: Class Int. Class Application No Lodged Complete Application No Specification Lodged Published Priority: Related art: TO BE COMPLETED BY APPLICANT Name of Applicant: Address of Applicant: Actual Inventor: Address for Service: ISTVAN NAGY 0 S 6 260 Fletclier Road, Largs North, State of South Australia, Commonwealth of Australia ISTVAN NAGY Care of COLLiSON CO., 117 King William Street, Adelaide, South Australia, 5000

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Complete Specification for the invention entitled: ANTI-THEFT DEVICE FOR VEHICLES The following statements is a full description of this invention, including the best method of performing it known to me: 2 This invention relates to an anti-theft device for vehicles and in particular to a device that blocks the supply of fuel to the engine of a vehicle.

Thefts of cars, in Australia, is a major area of concern and economic loss.

Various devices are known that aim to prevent theft of vehicles. Burglar alarms are common, however malfunction of these alarms is also common place and little more than casual notice is usually taken of such devices, because a proportion of those available are known to give false alarms.

Further many alarms are highly visible, and are easily located and inactivated by potential thieves.

Several devices are known that are intended to inactivate the vehicle such as devices to lock the free rotation of the steering wheel. A problem exists however with these devices in that they are readily visible and easily inactivated. Accomplished vehicle thieves are very adept at determining whether an anti-theft device is in operation, usually because a clear warning is given, or a switch or lock is easily visible.

A more effective way of protecting against theft is to immobilize the vehicle, 20 and this can be achieved by interfering with the supply of an essential substrate for the function of the engine of the vehicle, such as the fuel or electricity.

9oV.Q The invention could be said to reside in an anti-theft device for use in a vehicle, including an intercepting valve adapted in an intercepting position to block a flow path through a fuel line OT said vehicle and said intercepting valve being :biased to a closed position, a valve operating means adapted to maintain said intercepting valve in a non-intercepting position when an electrical current is supplied to the said valve operating means through a valve circuit, i. :and an actuation switch adapted in a first position to enable the said electrical supply to said valve operating means and in a second position to interrupt electrical current to said l'alve operating means.

It is found that the anti-theft device according to the invention very quickly inactivates a vehicle. A car can usually be started, and driven for a few hundred meters, but then stalls, with no more fuel available. The thief is thus 3 unaware that an anti-theft device is operating, and has not taken steps to inactivate the anti-theft device. Usually by that time the vehicle is in a position where it is embarrassing for the thief to attempt to inactivate the antitheft device and start the vehicle.

Further the use of an electrically energized intercepting valve, requires that the valve is energized before it can be maintained in an open position, and thus extraordinary difficulty is encountered in de-activating such a device, because destruction of the device does not allow for the use of the vehicle. It 1 0 is only upon activation by an electric current being supplied to the valve operating means that fuel is supplied to the engine. Therefore the potential thief has %,ery little option but to abort his theft.

Preferably the anti-theft device includes a switching means adapted in a first configuration to interrupt the said electrical supply enabled by said actuation switch, and in a second configuration to allow the said current supply.

According to a further form of the invention the switching means is biased to the first configuration and an electrical impulse through a switching circuit 20 effects a change in the switching means to the second configuration and the switching means is not changed to the second configuration unless current 0 o flows through the valve circuit to the valve operating means.

saoo 00 00 Preferably in the two abovementioned forms of the invention the actuation S 25 switch is the ignition switch of the vehicle.

o00 00*" In the preferred form of the invention referred to immediately above the valve 0*00 need not be put into the intercepting position using the actuation switch. The valve is automatically put into the intercepting position when switching off of the ignition switch. On switching the ignition on again the switching means prevents current from passing through the valve circuit, and only on 00 o. activation of the switching means is the valve opened. This embodiment 0 thus has the advantage of the user not having to remember to deactivate the valve.

In a preferable form the switching means is actuatable by a momentary switch.

In a preferable form the switch for actuating the switchirng means is hidden in the cabin of a vehicle so as not to be evident to a thief and in one form the hidden switch is a reed switch of the sort actuable by a magnet.

In this form the reed switch can be mounted anywhere in the vehicle cabin, and preferably behind a plastics sheet found in the vehicle cabin. Thus for example the reed switch can be mounted behind the upholstery in the door.

The switch for actuating the switching means can be of any sort, including a 1 0 coded switch such that a code has to be entered into a keypad, kept under a console. Alternatively the switch for actuating the switching means may be a mechanical switch.

In an alternate form the invention could be said to reside in the combination 1 5 of a vehicle fitted with any one of the forms of the anti-theft device described above.

In an alternative form the invention may be said to reside in an anti-theft device for use in a vehicle, including 20 an intercepting valve adapted in an intercepting position to block a S, 1flow path through a fuel line of said vehicle and said intercepting valve being biased to a closed position, a valve operating means adapted to maintain said intercepting valve in a non-intercepting position when an electrical current is supplied to the said valve operating means through a valve circuit, S: an actuation switch adapted in a first position to enable the said electrical supply to said valve operating means and in a second position to interrupt electrical current to said valve operating means, a switching means adapted in a first configuration to interrupt the said electrical supply enabled by said actuation switch, and in a second configuration to allow the said current supply, wherein an electrical impulse through a switching circuit effects a change in the switching means to the second configuration from the first configuration, and the switching means being not shifted to the second configuration unless current flows through the valve circuit to the valve operating means, and said electrical impulse is actuated by a momentary switch not observable from within the seating area of the vehicle and being responsive to a source of magnetic field being selectively positioned in close proximity to the momentary switch.

For a better understanding of the invention it will now be described with reference to figures wherein FIG. 1 is a circuit diagram of a first embodiment of an anti-theft device according to the invention, FIG. 2 is a circuit diagram of a second embodiment of an anti-theft 1 0 device according to the invention, and FIG 3 is a circuit diagram of a third embodiment of an anti-theft device according to the invention.

1 5 Referring to FIG. 1 there is provided a circuit for operating an electrically actuated intercepting vive 1, which can be maintained in a non-intercepting (open) position by the flow of electrical current maintained through a valve circuit 2 operable from the ignition switch 3. Electrical current passing through a solenoid 4 maintains the valve in an open position. A thyristor 5 is S 20 provided to block flow of current through the valve circuit 2, unless first Saactivated by a thyristor driver 6 whilst the ignition switch is in a closed position and current flows through the valve circuit, and in particular the :thyristor. Alternatively, thyristor driver 6 maintains drive to the thyristor so switch 3 can be closed i.e. ignition turned on. The thyristor driver is preferably activated by a momentary switch, and in one form is actuated by a o 0 reed switch being actuable by a magnet and the reed switch can easily be ao a hidden behind a panel or behind upholstery in the cabin of a vehicle.

Thus the electrically actuable intercepting valve is only kept open, if current 30 is maintained in the valve circuit 2. Current is stopped when the ignition 3 of 'a a the vehicle is turned off. However current is not returned to the valve circuit unless the thyristor is opened by an actuation switch operating the thyristor driver.

3 5 Referring to FIG 2 and a second embodiment of the invention an electrically actuable valve 1 can be maintained in an open position by electrical current flowing through a solenoid 4 supplied by a valve circuit 2 operable from the ignition switch 3. A first relay switch 7 is operable by a relay 8, to open the 6 valve circuit. A second relay switch 9 also operable by the relay 8 is provided in a switch circuit 10, so that the relay is only operable if first actuated by a further actuation switch 11. The means of operation of this embodiment is the same as for the first embodiment.

Referring to FIG 3 and a third embodiment of the invention the actuation switch is provided by a mechanical switch 12. In this instance the ignition 3 does not automatically inactivate the intercepting valve 1. Thus if the mechanical switch is left on then the valve can be actuated simply by the ignition switch, however if the mechanical switch is left off the ignition switch is not sufficient to reactivate the valve by itself and the mechanical switch 12 must first be switched on before the valve will open.

It is to be realized, however that a valve circuit where the actuation switch is not the ignition switch can also be used to maintain an electrical supply to the intercepting valve. Thus although a switching means may be desirable for further security, that is to say to be hidden from the view of a thief, the actuation switch itself can also be hidden from view and this simple arrangement can also provide a very useful anti-theft device.

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Claims (6)

1. An anti-theft device for use in a vehicle, including an intercepting valve adapted in an intercepting position to block a flow path through a fuel line of said vehicle and said intercepting valve being biased to a closed position, a valve operating means adapted to maintain said intercepting valve in a non-intercepting position when an electrical current is supplied to the said valve operating means through a valve circuit, an actuation switch adapted in a first position to enable the said electrical supply to said valve operating means and in a second position to interrupt electrical current to said valve operating means, a switching means adapted in a first configuration to interrupt the said electrical supply enabled by said actuation switch, and in a second configuration to allow the said current supply, wherein an electrical impulse through a switching circuit effects a change in the switching means to the second configuration from the first configuration, and the switching means being not shifted to the second configuration unless current flows through the valve circuit to the valve operating means, and said electrical impulse is actuated by a momentary switch not o observable from within the seating area of the vehicle and being responsive o to a source of magnetic field being selectively positioned in close proximity 4* 0 to the momentary switch. An anti-theft device as in claim 1 wherein said switching means is .004 either a thyristor or a relay switch. 00 S3. An anti-theft device as in either claim 1 or 2 wherein the momentary switch is a reed switch of the sort actuable by a magnet.

4. An anti-theft device as in claim 1, 2 or 3 wherein the switching means is a thyristor.

5. An anti-theft device as in claim 1, 2 or 3 wherein the switching means is a relay switch. 8

6. An anti-theft device as in any one of claims 1 to 5 wherein the actuation switch is the ignition switch for the vehicle.

7. The combination of a vehicle and an anti-theft device of any one of the preceding claims, wherein said anti-theft device is fitted to said vehicle

8. An anti-theft device as substantially as described in the specification, 1 0 with reference to and as illustrate by the accompanying figures. Dated this 26th day of June 1992. ISTVAN NAGY By his Patent Attorneys, COLLISON CO. a0 0 i