EP0379505A4

EP0379505A4 - Improvements in or relating to security device or alarm

Info

Publication number: EP0379505A4
Application number: EP19880907555
Authority: EP
Inventors: Dino Placido Calapai
Original assignee: Individual
Current assignee: Individual
Priority date: 1987-09-14
Filing date: 1988-09-02
Publication date: 1990-10-24
Also published as: EP0379505A1; KR890701394A; GB9005550D0; CN1031969A; WO1989002379A1; GB2228816A

Description

IMPROVEMENTS IN OR RELATING TO SECURITY DEVICE OR ALARM

This invention relates to alarms and other systems, generally called "security systems", emitting a signal, usually a whistle or other audible signal of suitably loud and penetrating quality, when a motor vehicle or other object or device is tampered with in some unauthorized manner by a potential thief or other unauthorized person, to whom I shall refer hereinafter as a "thief". The security systems to which the invention relates generally include:

1. A sonic (e.g. a conventionally-fitted motor- horn, or siren) and/or visual (e.g. head¬ lamps) signal emitter; 2. An on/off switch ("enabling"/"disabling" means) ;

3. Exit/entry delay means, so that the author¬ ized user ("owner") of the device (^'"car") can enable/disable the system while, for a minimum time interval, he is inside the car or is otherwise so acting or in such a situation as would trigger the signal emitter had he been a thief;

4. A detector of an "alarm condition"; 5. Means for activating the signal for a predetermined time interval (maximum is sometimes prescribed by law) after detection of alarm condition;

6. Means for resetting and re-arming the system after the signal has been activated;

7. Means for rendering useless the object of the attempted theft. In the case of a motor vehicle this may involve disabling the ignition system when alarm condition has been detected; 8. A back-up battery or other suitable unit to provide power for activating a warning device when wires are cut or the security system is otherwise tampered with, and 9. A detector of a condition in which the object is in regular or authorized use e.g. when the car ignition is on or when the motor is running - to avoid or minimize the likelihood of actuating the alarm when the vehicle or other object is in lawful use.

In the past, enabling/disabling means for a vehicle security system have included:- Hidden on/off switches; Key-switches ; Electronic combination key-pads;

Various remote control devices, and Connections to vehicle ignition switch Such devices have often made the installation of security devices cumbersome and time-consuming and apt to cause damage to the vehicle and its fittings, unless carried out with reasonable skill and proper tools. The location of the central alarm control unit has generally required the installer to pass wires through the vehicle firewall, and sometimes to dis- mantle the dashboard, in order to effect electrical connections required by hidden on/off switches, key- switches, combination key-pads, or to effect connec¬ tions involving the^'ignition-switch.

Furthermore, prior remote control devices for alarm systems have sometimes given rise to difficulties and potentially dangerous situations e.g. by enabling or activating the system while the ignition is on, or when the vehicle is in motion, which can prove parti¬ cularly hazardous, especially if the "disable" should operate on the ignition. An object of the invention is to facilitate the installation of a motor vehicle security system.

Other objects and advantages will become apparent hereinafter. Accordingly the present invention provides a security system for a motor vehicle or other apparatus having an engine bay or compartment and a control cabin separated therefrom, for emitting an alarm when the apparatus is tampered with, the system including a signal emitter and switch means for enabling or disabling the system, characterized in that the system including said- switch means is containable wholly within the engine bay and is operable independently of wiring to the control cabin, the switch means being not directly associated with cabin controls but with one or more points in the engine bay which is or are respons¬ ive to operation of a cabin control.

But in order that the invention may be better understood, reference will now be made to the accom- panying drawings which are to be considered as part of this specification and read herewith. In the drawings: Figure 1 shows diagrammatically the manner of installation of typical prior units, showing the need to drill holes from the dashboard into the engine bay. ^'By contrast, Fig. 2 shows, also in a general¬ ized manner, a system according to the present inven¬ tion and a manner of installing it;

Figs. 3 and 4 show a system according to the invention in further detail; Fig. 5 shows how the invention can simplify installation of other automotive products, in this case an electric fan for a radiator, and

Fig. 6 is a diagram showing an application of the invention to a motor car having an alarm triggered by current and/or voltage surge caused by turning on a boot or cabin light.

Referring to the drawings in more detail, wherein like reference numerals denote like parts, Fig. 1 shows the lay-out of a typical known type of alarm applied to a motor car wherein fire-wall 7 separates engine bay and dashboard areas denoted generally by 8 and 9 respectively. Alarm unit 10 is activated by switch 11 responsive to an alarm condition and is wired in circuit with ignition coil 12 and also, through fire-wall 7, with an ignition switch and fuse-box, by way of leads 13, 14 respectively.

Fig. 2 shows an arrangement in a practical embodiment of the- present invention, wherein the unit and connections are housed entirely within an engine bay. The unit is controlled by a remote-control transmitter 15. Power is obtained from the car battery 16. Switch 11 detects opening of the car's hood or "bonnet" .

Fig. 3 shows components of the unit indicated generally by 10 in Figs. 2. A signal from transmitter 15 is picked up by antenna 17 of remote-control receiver 18 which is connected to ignition detector 19 and entry and exit delay circuits 20 and 21 respective¬ ly. Detector 19 is capable of detecting "ignition on" and "motor running" .

The exit delay provided by 21 may be variable within suitable limits. This circuit is directly associated with mechanical switch, motion, shock/jacking and current-sensing detectors 22 to 25 inclusive, respectively. Each is responsive to an emergency situation indicated by various kinds of interference with the car. Mechanical switch detector 22 is connected to a 12-volt line 26 via switch 27, and to ground via switch 28. Ultra-sonic transducers 29 are associated with motion detector 23. Battery back- up 30, with tamper-sensing means, is connected across vehicle battery 16 and also to delay circuit 21 as shown.

Central locking circuit 31 is connected via links 32, 33 and 34 to circuits for wind-up electric windows, for "unlock doors" (off) and "lock doors" (on) respectively, is also connected to receiver 18.

Entry delay circuit 20 is connected to a concealed siren 35, and to the car horn and headlights 36 and 37 via pulsing relay 38. Circuit 20 is also connected via ignition disable relay 39 to the negative of coil 12, to the positive of which is connected ignition detector 19. Circuit 20 is further connected to solenoid 40 via relay 41 for starter motor, fuel valve or the like.

Ignition detector circuit 19 is associated with wiper motor^' or alternator/generator circuit 42.

In Fig. 4, ^'which illustrates a practical embodiment of the invention in a somewhat simplified form, control unit 43 includes back-up battery (shown as 30 in Fig. 3) , siren (35) and shock sensors (23 and/or 24) . Also associated with the unit shown generally as 43 are door/bonnet/boot etc. switches 44, a power/current sensing circuit 45 and an ignition/"motor running" detection circuit 46 with connections 47 to the car ignition switch and 48 to the generator and/or alternator regulator.

. Circuit 49 is for detection of "motor running" and includes coil 40, ignition disable switch 41 and distributor 51.

Unit 44 also has a connection 52 to a central locking function.

Fig. 5 shows how the invention may be applied to activate fan 52 only when the car engine is running at a desired minimum speed. By monitoring the positive terminal of coil 12, one is able to determine whether the engine is running and a signal therefrom can activate relay 53 associated with the fan. Circuit 54 monitors the switching frequency on the positive terminal of coil 12 and, when appropriate, provides a suitable voltage output to relay 53.

Fig. 6 shows how the invention can be applied to a car wherein an alarm is triggered by current and/or voltage surge caused by turning on a boot or cabin light. In such a vehicle, opening of a boot or "trunk" compartment 55 causes ignition of a small light-globe 56 to light the boot interior, and a higher-powered light-globe 57 in cabin area 58 is ignited merely by lifting or some other operation on a door-handle prior to opening the door.

Unfortunately there was a temptation for owners of such vehicles to switch off these systems, because alarms could be easily activated by idle playing e.g. by children who had neither the intention nor, maybe, the ability, to gain entry to the cabin and misuse the car.

In an attempt to overcome this problem, some recent makes of motor car use the following apparatus which avoids the need to use current (or voltage-drop) sensing methods. An alarm system is installed in the engine bay. Wires are then run through to a movement detector in the cabin and also to a switch detecting opening of a boot lid. The multiplicity of wiring and wall penetrations can render such methods cumbersome, expensive- and labour-intensive. Three to four hours can be required to install such apparatus.

It will be recalled that the system described according to the first form of the present invention - particularly with reference to Figs. 2 to 5 - used a basic five-wire system with all wires connected to points in the engine bay which are electrically or otherwise- activated in direct or indirect response to the activation of a control in the cabin e.g. by switching on an ignition switch. This greatly reduced installation time - sometimes to as little as 20 minutes. The basic idea is to simplify installation by avoiding the need to penetrate fire-walls and the like to run the necessary wiring. The first system of the present invention used current-sensing to monitor the vehicle's doors and boot.

If the first system were applied to a car with the "door handle" option described above, it could be prone to "false triggering" also, and would have to be installed with full wiring requirements in order to be efficient.

It has been found that simple additions to the' first system may be applied towards a solution of the "door-handle option" problem, and should increase installation time by about 10 minutes only. This is now described by reference to Fig. 6 herewith.

Two current (or voltage-drop) sensing detectors are incorporated into the alarm system. The first is adjustable to trigger on a small current surge caused by or typical of igniting the boot interior lamp, which in turn is caused by actually opening the boot lid and not merely by idle playing with the boot lid handle. The second is adjustable to trigger on a larger current surge corresponding to igniting the cabin interior light.

Hence when the boot is opened the first detector is activated.

When the door is opened (or the handle lifted) both detectors are activated. The two detector outputs can be electroni- cally processed e.g. by logic circuits or in any other known manner, to determine whether the boot has been opened or-the door handle operate .

^• Now we use the above analysis to determine whether the boot has opened. We ignore the larger current surge resulting from the door opening or door handle being lifted.

A movement detector is placed inside cabin 58. This movement detector detects movement within the cabin area (and also the opening of doors) . When a movement is detected, this unit switches an electrical load 60 across the vehicle's electrical system. This load has electrical characteristics similar to the boot lamp 56. Therefore we use the- same analysis of current surge (or voltage drop) to determine whether the boot lid has opened or whether the^movement detector has triggered. The current surge resulting from the mere opening of cabin doors or lifting of door handles is completely ignored. Therefore the unit can be installed by mounting the central unit 10 in engine bay 8 (as in the first form) and connecting the five wires to i) Battery positive ii) Battery negative iii) coil negative (or similar functional point) iv) coil positive (or similar functional point) v) Switch 61 in bonnet to detect opening

Additionally i) Mounting of movement detector 59 within cabin 58. ii) Applying power to this movement detector. Therefore the movement detector does not require wiring back to the unit in the engine bay and a boot lid switch is not required. Thus movement detector triggering is detected by the car alarm as a current surge (or voltage drop) across the vehicle's electrical system. The opening of the boot (and turning on of lamp in the boot) is also detected as a current surge. Lifting of door handles causes a "larger" current surge (or voltage drop) than the boot lamp or movement detector. A larger current surge (or voltage drop) results due to there being many lamps inside the cabin and the lamps are also more powerful than those in the boot. This detection is therefore ignored.

Some cars have very low power lamps to facilitate insertion of keys into locks etc. Such lamps could be harmlessly activated in like manner to the interior cabin light. Current and/or voltage surges due to such lamps can be electronically ignored in the same way.

Hence mere "nuisance" or false alarms are reduced, as is the installation time.

Although the advantages of the invention have particular reference to motor vehicles, it is to be understood that the invention is also applicable to other tangible items of property.

Claims

The claims defining the invention are as follows:

1. A security system for a motor vehicle or other apparatus having an engine bay or compartment and a control cabin separated therefrom, for emitting an alarm when the apparatus is tampered with, the system including a signal emitter and switch means for enabling or disabling the system, characterized in that the system including said switch means is containable wholly within the engine bay and is operable independ¬ ently of wiring to the control cabin, the switch means being not directly associated with cabin controls but with one or more points in the engine bay which is or are responsive to operation of a cabin control.

2. A system as claimed in claim 1 wherein the cabin control is an ignition switch.

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3. A system as claimed in claim 1 or claim 2 responsive to current and/or voltage surges due to activation of^" a first device such as a boot interior lamp (which activation would indicate harmful activity) and to activation of a second device such as a cabin interior lamp (which activation does not, of itself indicate harmful activity) characterized by correspond¬ ing first and second detectors, and a third detector such as a movement detector associated with the second device but having electrical characteristics comparable with the first device, and means for electronically processing the outputs of said detectors to prevent triggering of the alarm when activity is harmless.

4. A security system substantially as herein described with reference to Figs. 2 to 6 of the accompanying drawings.