WO1994029148A1

WO1994029148A1 - Vehicle immobiliser

Info

Publication number: WO1994029148A1
Application number: PCT/GB1994/001199
Authority: WO
Inventors: Steven Alfred Williams
Original assignee: Rondish Company Limited
Priority date: 1993-06-03
Filing date: 1994-06-02
Publication date: 1994-12-22
Also published as: AU6851794A; ZA943858B

Abstract

A vehicle immobiliser including a main controller (30) for immobilising a vehicle by closing a valve (52) in a fuel line of the vehicle. The controller (30) is arranged to respond to various signals relating to unauthorised use of the vehicle and additionally to control signals generated by operation of a standard pager (50). The pager (50) is mounted in the vehicle and on receipt of its own coded radio signal from a pager network station initiates operation of the vehicle immobiliser.

Description

VEHICLE IMMOBILISER

The invention relates to vehicle immobilisers.

Vehicles, and their cargoes if commercial vehicles, are frequently stolen and often their authorised drivers abused or assaulted by the thieves. Many vehicle security systems are already known and in particular it is known to provide a driver with a radio transmitter whose output signals are used to inhibit an in-built immobiliser so that if the driver and vehicle becomes too far separated, the vehicle engine will stop - see for example UK Patent Specification 2233487. It is also known to arm and disarm a vehicle immobiliser or alarm system with a short range hand-held radio (or other, for example ultra-sonic) transmitter.

It is an object of the invention to provide a remotely operable vehicle immobiliser.

According to the invention there is provided a vehicle immobiliser system for disabling an electrical or fuel supply of the vehicle, and a radio receiver for supplying control signals to the immobilising device, in which the radio receiver is a pager tuned to respond normally to unique digital coded radio signals transmitted by a remote radio station to produce the control signals.

The pager may have a light emitter arranged to light up on receipt of the coded radio signals, and means for monitoring a supply of current to the pager and producing the control signals when the power consumed by the pager increases due to the light emitter being lit up indicative that the coded signals have been received.

An in-line fuel valve or an electrically operated fuel pump may be included and arranged to respond to the control signals to cut-off the fuel supply.

An intermediate controller may be arranged to control the valve or to cut-off the electrical supply to the pump intermittently and progressively for longer periods of time on receipt of the control signals.

The immobiliser may comprise a central controller programmed to immobilise the vehicle, a key pad for use by an authorised user to initiate and control the central controller, a hand-holdable remote switch for transmitting control signals to the main controller, and a pager for receiving its uniquely coded radio signals from a remote pager network radio transmitting station and for causing the main controller to immobilise the vehicle in that event.

An alarm may be included which is arranged to be initiated by radio signals transmitted by the switch.

Pagers per se are already well-known and used for personal use. A "standard pager" as is well understood by persons skilled in the art comprises a small radio receiver, mounted in a small container having a simple cell battery. The receiver is tuned to receive radio transmissions and each pager is programmed, normally at the point of manufacture, to respond to a unique or individual code represented by a few or several different digits, say 10 to 12. On receipt of radio signal carrying its own unique code, the pager is arranged to alert its user normally by causing a light (LED) to flash and usually optimally a bleeper to sound. In addition, the pager has a screen to provide information to the user to indicate where or to whom he should return the call.

A vehicle immobiliser system according to the invention will now be described by way of example with reference to the accompanying drawings in which: -

Figure 1 is an electrical diagram showing an immobilising device for a vehicle disabling its engine, the vehicle being fitted with a basic alarm system;

Figure 2 is an electrical diagram showing an immobilising device for a vehicle having a radio controlled alarm system; and

Figure 3 shows part of the system of Figure 2 and a radio signal receiver in the form of a pager.

Referring to the drawings, in Figure 1, a vehicle is generally represented by reference numeral 10. A basic car alarm system 20 is also fitted to the vehicle. This type of alarm system is operated by a central door locking mechanism 11 which locks all the doors simultaneously. The central door locking mechanism varies between makes and models but the essence of the operation is similar. When the door locking mechanism is operated to lock the doors, it activates the alarm system, normally with a slight time delay. When the door locking mechanism is operated to unlock the doors, the alarm is deactivated.

Some alarm systems require the door key to be turned a little further than usual and held for a short period, say 1 or 2 seconds, to "deadlock" the vehicle in which the doors cannot be unlocked from within and to activate the alarm. Sensors are used to prevent activation of the alarm when the ignition switch is turned on.

The immobilising devices shown in Figures 1 and 2 have main controllers 30 including electrical processing units (not shown) . The controllers are relatively small and thus can be mounted in or under the vehicle in a number of locations including within an engine compartment or boot, so that they are difficult to detect.

Connected to the controllers 30 by electrical wires are disabling means 31. In keeping with the design philosophy of making the disabling device as hard to detect as possible, the disabling means may take many forms and may include either singly or in combination, an electrical disabling means or a fuel disabling means. The use of multiple electrical disabling means adds to the effectiveness of the device, while the fuel disabling means is the more preferred.

Examples of electrical disabling means include ignition shorting/isolation, starter motor isolation (usually by isolating the starter motor solenoid) and fuel pump isolation (if an electrical fuel pump is used) . Examples of fuel isolation include a solenoid valve fitted into the fuel supply line to the engine which, when the device is armed, turns off the fuel supply to the engine.

The system is controlled by a hand holdable remote switch 32, preferably of the radio frequency type using a coded signal. The controller recognizes operation of the remote switch to arm and disarm the device. This is the device in its basic form. However, optional features as shown in Figures 1 and 2 include an indicator, a manual override switch, passive arming, and an alarm interface.

An indicator in the form of a flashing LED 33 and/or a buzzer 34 may be connected to the controller to indicate that the system is armed. A flashing LED is not recommended for most situations as it provides a visual indication to a would-be thief that the system is fitted to the vehicle and also provides a starting point for tracing the location of the components of the system.

A keypad 35 is provided for use with the system and is used to disarm the immobiliser with a secret code. The keypad may also be operated in valet mode using a changeable 'valet' code when the vehicle is being parked or serviced, avoiding handing the coded radio remote control to a valet park driver.

A further feature is the provision of passive arming of the system. This is where the system automatically arms a predetermined time period after the last door is closed. The delay is typically 8 to 30 seconds. The system, as is usual for alarm systems, will not arm while the ignition key is turned on. The passive or automatic arming sequence begins when the ignition switch is turned off and a door is opened. The delay period countdown starts when the last door is closed. Re-entry into the vehicle during the delay period resets the countdown. The delay allows time from the door being closed for re- entering the car (or trunk) and the auto-arming sequence starts again from the last door closure. The closing of the last door may be detected by a connection to either a door switch or to a courtesy light of the vehicle (generally indicated by 36) .

For vehicles fitted with an alarm system, the immobiliser system may be interfaced to the alarm for operating the alarm system. This is achieved by providing an alarm interface connected to the controller 30.

In Figure 1, the vehicle 10 is shown fitted with a basic alarm system which is operated by a central door locking mechanism. Normally when the driver's door is locked, all doors of the vehicle are also locked and when the driver's door is unlocked, all doors are unlocked. A central switch inside the vehicle may also lock and unlock all doors. The alarm system is connected to the central door locking mechanism 11 to activate the alarm when the doors are locked and deactivate the alarm when the doors are unlocked. This type of system is easily overcome by a would be thief by forcing the door lock of the vehicle.

The alarm interface of the device of Figure 1 includes a connection 37 to the central door locking mechanism of the vehicle such that when the device is armed, the door locking mechanism operates to lock the doors which in turn, activates the alarm system and when the device is disarmed, the doors are unlocked deactivating the alarm. In this way, there is no direct connection between the alarm system and the disabling device and overcoming the alarm will not overcome the device while allowing the device to control the alarm system so that a single remote switch will arm the device, lock the doors and activate the alarm system.

For the more complicated door lock activated alarm system, the interface provides the necessary signals to lock the doors and to activate the alarm via the door lock connection.

In the passive arming procedure, the controller may be arranged such that on passive arming the doors are not locked and the alarm is not activated. In this arrangement, called partial passive arming, the vehicle will still be disabled by the device but not protected by the alarm which may be an advantage if the vehicle is left standing while infrequently attended such as when loading or unloading goods.

In complete passive arming, the doors would be locked and the alarm activated when the device arms, say 10 seconds after the last door is closed.

An anti-scanner 40 is diagrammatically shown connected to the controller 30 for interrogating the signal received from the remote key. Normally, in practice, the anti-scanner is part of the electronics of the controller and not a separate item located outside of the housing.

In Figure 2, the vehicle is fitted with a radio controlled alarm system 25. In this arrangement, the alarm interface includes a radio transmitter arranged to send a coded signal to the alarm system to operate the alarm. In this arrangement, there is no physical connection between the alarm and the disabling device but still operation of the device effects operation of the alarm system. So again the alarm is controlled by the device and a single remote switch can operate the device and the alarm. Overcoming the alarm system again does not affect operation of the disabling device leaving the vehicle or engine inoperable. Accordingly, when the device is armed, it sends a coded signal to the alarm system to activate the alarm and when the device is disarmed, it sends a coded signal to the alarm system to deactivate the alarm.

In Figure 3, a pager 50 comprises in a 'standard' pager. The pager 50 is programmed usually when manufactured to respond to digital code carrying radio signals within a frequency band allocated for any particular or chosen pager communications network. Usually the digital code is about 10 digits long. On receipt of its own set code radio signal, the pager is turned ON to display its call station number or other material on its screen (not shown) . The pager 50 is provided with electrical power via an interface circuit 51 from a vehicle battery, which circuit 51 provides control signals to the main controller in the housing 30. The immobiliser in this arrangement consists of an in-line solenoid operated valve 52 in a fuel supply line of the vehicle. The valve 52 is arranged to be turned ON and OFF by the main controller 30.

In use, when the pager 50 receiver receives coded signals, representing its own code, its display will light up. Normally an LED will flash and a bleeper activated. This is in accordance with a normal operation of a standard pager receiver. As a result the power required to drive the pager increases noticeably to drive the LED, albeit only very small power is required overall, and the interface circuit 51 which monitors power to the receiver 50 detects the increase of power as a control signal. Responding to the control signal, the interface circuit 51 supplies electrical pulses to the main controller invoking the sequence for immobilising the vehicle. In practice, the pager 50 is left with its bleeper turned OFF but there is still a significant change in power to the receiver 50 whenever coded signals are received.

The pager 50 and the interface circuit 51 are preferably mounted in a sealed container and a battery compartment, normally provided in the pager housing, provided with a "dummy" battery. The dummy battery consists of a positive and negative terminal mounted on a central body which fits in to replace a normal single battery cell. This means that the normal battery compartment and the pager battery connection need not be altered. The central body is provided with wires to connect the positive and negative terminals to the interface circuit 51 as required.

In normal operation when the pager 50 receives its coded signal, the LED is turned ON and OFF about once or twice per second giving a clear and regularly pulsed change in power consumption. The interface circuit 51 is preferably arranged to respond to the pulsed changes, say over a period of three or four seconds, so as not to be initiated by random or transient changes which may otherwise result in malfunctions.

Further, it is preferably arranged in some applications that a delay is provided before the vehicle is immobilised and a buzzer, say, sounded for the driver. Such a buzzer can alert an authorised driver and give time for cancelling the imminent immobilisation of the vehicle by entering an authorised or appropriate number onto the key pad 35.

In this preferred embodiment, the main controller turns OFF the valve 52. This may be done as one step or as a series of steps, in which latter case an intermediate controller is provided to control the valve to turn OFF for intermittent and increasing periods of time. If the series of steps is used, the driver of the vehicle will more likely have the impression that the vehicle has developed of its own or independent accord some running fault and not suspect that some anti-theft system has been initiated. The main controller 30 is also arranged thereafter to continue to immobilise the vehicle until some special switching or instruction is carried out, such as for example by using a key pad input (not shown) .

It may be necessary for safety reasons to temporarily inhibit immobilising the vehicle until the vehicle has stopped moving or is only moving at a slow speed. In such a case, an inhibitor circuit is included in the controller 30 which is controlled by a monitor circuit in a speedometer of the vehicle. Thus, in the described arrangement, the vehicle can be stopped by remote signalling using a usual pager network system. Normally, pager networks operate with local land-based radio transmitters, but satellite paging networks could also be used. In any event, in order to immobilise a vehicle in the manner described, an authorised user contacts the pager network central controller, usually by telephone, and immediately arranges for his own vehicle pager code to be transmitted. The described system responds as described and the vehicle will automatically become immobilised.

One advantage over the earlier proposals is that the authorised user or owner of the vehicle can cause the vehicle to become immobilised when he is separated from the vehicle by a great or significant distance. As such, the personal security of the authorised user cannot be immediately under threat.

The arrangement described with reference to Figure 3 may be used with a dedicated or separate controller 30 rather than, as described, an additional part of an immobiliser and alarm system operable independently.

It will be noted in any event that in embodiments of the invention, standard pagers can be used without any changes physically or electrically being required to the pager. Pagers are readily available, well-tried and comparatively inexpensive. Thus, vehicle immobilisers can be simply and readily provided which significantly extend the effect and usefulness of already proposed immobilisers. This is not least so because the pager calling systems, the base radio _transmi_tter stations, are already well established in most commercial regions of the world. Also, the signals transmitted by the base radio transmitter stations are standard signals; no especial alterations are required for sending vehicle immobilising signals to the described vehicle immobilisers.

It will also be noted that standard pagers can be programmed to respond to more than one coded signal, often four different coded signals. When appropriate different signals could be used to immobilise a vehicle in a different way, say, by ignition cut-out or fuel turn off using two respective different coded signals. It is also possible to arrange for a coded signal to initiate the pager to provide for remote starting the car (and turning on the vehicle heater or air conditioner), or simply to open the doors remotely when the vehicle keys have been locked inadvertently inside by the authorised driver/owner.

It will be appreciated that the bleeper of the standard pager may be left ON in which case the change in power supplied to the pager is somewhat greater when it receives a coded signal. In either case, no modifications are required to the electrical parts or components of the pager and no expertise or knowledge of its normal operations are required. A standard pager tuned to allocated frequencies and codes of any country may be "plugged in" and used for immobilising a vehicle in a respective country.

It has been mentioned when the disenabling device is armed it can send a coded signal to an alarm device. It is also possible to arrange for the car alarm to provide a signal to the pager to initiate immobilisation of the vehicle.

It is also possible to provide a hidden switch inside the vehicle or arrange with the use of a small radio transmitter carried by an authorised user to generate a suitable coded signal for the pager. In a typical hi-jack situation it may be advantageous to arrange for a delay, typically three or four minutes, before the immobiliser sequence or action is taken by the device. Such arrangements are useful, especially for commercial vehicles, where the vehicle may be located outside the range of a particular terrestrial paging communications network.

An immobilising device according to the invention may be connected to operate the vehicle hazard lights, horn or separate siren. After a preliminary warning on activation of the pager, for say half a minute, an immobilising sequence begins and the lights continue to flash and the horn or siren remain ON. Normally, the vehicle will be slowed down by the unauthorised driver until below say 10 or 15 miles per hour, whereafter, as mentioned earlier, the fuel and/or ignition is cut-off. It is likely that the unauthorised driver will then abandon the vehicle so that it can be recovered by the authorised user or the police. If the police are close in attendance, the unauthorised driver can be readily identified and possibly apprehended as the vehicle lights, and siren say, will remain ON.

Claims

1. A vehicle immobiliser system including an immobilising device for disabling an electrical or fuel supply of the vehicle, and a radio receiver for supplying control signals to the immobilising device, in which the radio receiver is a pager tuned to respond normally to unique digital coded radio signals transmitted by a remote radio station to produce the control signals.

2. A system according to claim 1, in which the pager has a light emitter arranged to light up on receipt of the coded radio signals, and means for monitoring a supply of current to the pager and producing the control signals when the power consumed by the pager increases due to the light emitter being lit up indicative that the coded signals have been received.

3. A system according to claim 1 or claim 2, including an in-line fuel valve which is arranged to respond to the control signals to cut¬ off the fuel supply.

4. A system according to claim 1 or 2, including an electrically operated fuel pump, in which its electrical supply is arranged to be cut-off in response to the control signals.

5. A system according to claim 3 or 4, including an intermediate controller arranged to close the valve or cut-off the electrical supply to the pump intermittently and progressively for longer periods of time on receipt of the control signals.

6. A vehicle immobiliser system including an immobiliser for disabling the ignition or fuel supply of the vehicle, the immobiliser comprising a central controller programmed to cause the vehicle to be immobilised, a key pad for use by an authorised user to initiate and control the central controller, a hand-holdable remote switch for transmitting control signals to the main controller, and a pager for receiving uniquely coded radio signals from a pager network radio transmitting station and for causing the main controller to immobilise the vehicle in that event.

7. A vehicle immobiliser according to claim 6, including an alarm incorporating a radio receiver and in which the switch is arranged to transmit radio signals for setting the alarm.

8. A pager arranged to be mounted in a vehicle and electrically connected to a vehicle immobiliser system, in which the pager responds in use to a unique coded radio signal from a pager network radio transmitting station to provide control signals to immobilise the vehicle.