GB2170633A - Vehicle theft alarm - Google Patents
Vehicle theft alarm Download PDFInfo
- Publication number
- GB2170633A GB2170633A GB8431694A GB8431694A GB2170633A GB 2170633 A GB2170633 A GB 2170633A GB 8431694 A GB8431694 A GB 8431694A GB 8431694 A GB8431694 A GB 8431694A GB 2170633 A GB2170633 A GB 2170633A
- Authority
- GB
- United Kingdom
- Prior art keywords
- alarm system
- alarm
- vehicle
- sensing
- circuit
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Classifications
-
- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B25/00—Alarm systems in which the location of the alarm condition is signalled to a central station, e.g. fire or police telegraphic systems
- G08B25/008—Alarm setting and unsetting, i.e. arming or disarming of the security system
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60R—VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
- B60R25/00—Fittings or systems for preventing or indicating unauthorised use or theft of vehicles
- B60R25/10—Fittings or systems for preventing or indicating unauthorised use or theft of vehicles actuating a signalling device
- B60R25/1001—Alarm systems associated with another car fitting or mechanism, e.g. door lock or knob, pedals
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60R—VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
- B60R25/00—Fittings or systems for preventing or indicating unauthorised use or theft of vehicles
- B60R25/10—Fittings or systems for preventing or indicating unauthorised use or theft of vehicles actuating a signalling device
- B60R25/1018—Alarm systems characterised by features related to the general power supply
Abstract
An alarm system primarily for use in a vehicle comprises security switch means (16, 17) to permit of arming or disarming of the device only by an authorised person and connector means (12) to enable connection of the alarm system to a vehicle electrical supply circuit, the alarm system including sensing means adapted to sense any change in the voltage or current of the vehicle electrical supply system and if such change is sensed, to generate an alarm signal. The alarm system (10) includes its own power supply operative to generate an alarm signal if an attempt is made to disconnect the alarm system from the vehicle electrical supply. A plurality of security switches are disclosed including:- key switch; combination switch; coded electronic switch; radio remotely controlled switch. <IMAGE>
Description
SPECIFICATiON
Alarm systems
This invention relates to alarm systems and is primarily, but not exclusively, concerned with alarm systems for use in vehicles.
Alarms for use in vehicles are well known and comprise a variety of different sensing devices which may for example detect movement of the vehicle, the opening of a vehicle door, or sense directly the presence of an intruder and, when the alarm senses an intruder or other "untoward" event, the alarm will sound either by energising the horn normally provided on such vehicles or via an additional or separate audible warning device which is powered by the battery normally provided in motor vehicles.
Known alarms suffer from the disadvantage in that some are difficult to connect into the wiring of a vehicle, which wiring can sometimes readily be traced so that the alarm may be rendered inoperative by an intruder, and furthermore if the vehicle battery is disconnected from the vehicle electrical circuit such alarms are rendered inoperative.
It is an object of the present invention to provide a new or improved alarm system that overcomes or minimises the problems mentioned above.
According to the present invention 1 provide an alarm. system comprising in assembly a sensing means adapted to sense a predetermined event, alarm signal generating means responsive to the sensing of an event to generate an alarm signal, power supply means for energising said sensing means and said alarm signal generating means and "security" switch means for rendering said system operative or inoperative.
It is preferable for the sake of security that said sensing means, said alarm generating means power supply means and said security switch means are in close proximity to each other and preferably they are provided on a mounting part or plurality of mounting parts connected together and conveniently may be positioned within an enclosure member of a form which provides a tamper-proof casing so that access to the inside of the enclosure would take an unauthorised person some considerable time.
Preferably, said sensing means comprises a voltage or current sensing circuit and is adapted to be connected to an electrical circuit of a vehicle.
Preferably, when the object to be protected is a vehicle, said alarm system is provided with means whereby it may be readily connected to the electrical circuit provided in the vehicle.
Conveniently, said connection may be made through a plug provided on the device adaoted to fit in an electrically operated cigarette lighter provided on the vehicle or any other convenient access point to the vehicle electrical circuit.
Preferably, said alarm system comprises not only said alarm signal generating means but an audio electrical transducer whereby said signal may be transformed from an electrical signal to an audio signal. Conveniently, said transducer comprises a siren or other audio alarm signal device.
Said security switch means may comprise a key operated switch, a combination switch or may comprises an electronic switch operated by an electrical signal, for example a binary coded digital signal.
Wheras the security switch means is operative to energise or de-energise the alarm system, the means for operating the switch may be located remote from the circuits providing said alarm and.may, for example, comprise a key-operated switch mounted so as to provide an access thereto from outside the vehicle, or for example, may comprise an electronic switch operable by a transmitted signal thus enabling arming or dis-arming of the alarm system from outside the vehicle.
Preferably, said security switch means comprises an electrical circuit the characteristics of which are known and to which the alarm system responds when connected thereto to activate or deactivate the alarm system.
The alarm system of the present invention is particularly suitable as a vehicle alarm and in which case said sensing circuit may comprise a voltage sensing circuit.
Whilst it is envisaged that the sensing circuit may detect any change in the voltage of the vehicle electrical syste, preferably the sensing circuit detects only a drop in the voltage of the vehicle electrical system.
When the sensing circuit is connected to the vehicle circuit, via for example a cigarette lighter provided on the vehicle, any change in the voltage of the vehicle electrical system sensed by the sensing circuit will be detected and can be used to cause operation of the alarm signal generating means which may sound an audible signal produced by a siren for example.
Vehicles are usually provided with door operated switches which, on opening of the door, operate a light inside the vehicle and thus operation of the switch by opening a door will effect the voltage sensed by the sensing circuit causing operation of the alarm system. Any intruder thus entering the vehicle will cause operation of the alarm.
Likewise any attempt to start the engine will cause a change in the voltage sensed once again leading to operation of the alarm system.
The alarm system of the present invention, since it includes its own power source, is not dependent upon the vehicle electrical supply power, i.e. the vehicle battery, thus discon nection of the vehicle battery will only result in the alarm device generating an alarm signal since the voltage sensed by the sensing circuit will alter to zero.
A further significant advantage is provided by the alarm system of the present invention, particularly in its use as a vehicle alarm since connection to the vehicle is simple, as aforementioned it may simply plug into the cigarette lighter socket normally provided on vehicles and, since the sole purpose of the connection is to monitor the voltage of the electrical system, any unauthorised attempt to disconnect the alarm system from the vehicle will result in the sensed voltage changing and thus the alarm system will operate. Not only is the connection of the alarm system to the vehicle simple but also there is no need for the connection to be inaccessible or hidden.
Preferably, the alarm system includes a timer circuit to provide delays to permit the alarm system to be set and allow the operator to leave the area protected by the alarm prior to the device becoming fully operative.
Similarly, the same or a different timer circuit may be provided to permit of entry to the protected area, such timer circuit giving sufficient time for the alarm system to be rendered inoperative only by the authorised "key" means. If the alarm system is not switched off within a reasonable period of time, the alarm will operate as if it sensed an intruder.
Preferably the security switch means comprises an electrically conductive path having a certain resistance, reluctance, or reactance or a combination of same, and said alarm system includes a switching circuit which in response to connection thereto by said conductive path of predetermined reluctance, reactance or resistance causes the switching operation to take place.
Such a "key" feature enables a simple to operate "lock" since the device simply has to be connected through, for example, a jack plug and jack plug socket, and by changing the values in both the alarm system circuit and in the key, a very large number of different "combinations" may be provided.
One example of the invention will now be described in detail, by way of example only, with reference to the accompanying drawings, wherein:
Figure 1 is an illustration of the alarm system connected to a vehicle electrical circuit;
Figure 2 is a circuit diagram of one embodiment of alarm system;
Figure 3 is a circuit diagram of an alternative embodiment of alarm system.
Referring first to Fig. 1, the alarm system is provided with an enclosure in the form of a casing 11 in which the sensing circuit, the alarm signal generating circuit and the power source is provided and, where provided the audio signal generating device may also be enclosed, the alarm system 10 being provided with a flexible connector lead 12 terminating in a plug 13 adapted to fit in the cigarette lighter 14 normally provided in vehicles.
As an alternative to the plug 13, any suitable connection means may be provided whereby the flexible lead 12 may be connected to the vehicle electrical circuit.
Referring now to Fig. 2, the circuit illus trated therein shows one embodiment of alarm system of the present invention.
The circuit shown in Fig. 2 may be subdivided into different parts.
The part generally indicated at 20 comprises security switch means in the form of an electronic lock circuit and comprises a switch which has an electrical socket, for example a jack plug socket 16, and a key generally indicated at 17 which itself may comprise a jack plug 18 to which is connected an electrical circuit 19.
To keep the alarm system inoperative, the key 17 remains in position in the socket 16 and to arm the circuit, the key is removed. On removal of the key a signal is sent via operation amplifiers OP1 and OP2 to transistors TR and TR2, the latter of which conducts thus energising relay coil RL1 and closing relay contact RLC1.
A sensing circuit 21 is connected via flexible lead 12 and plug 13 to the vehicle electrical circuit and any change in voltage across terminals 26 and 27 will cause an instantaneous change at terminal T, connected to one input of operational amplifier OP3 and cause a change, not instantaneous, at terminal T2 since capacitor Cl will take finite time to charge or discharge to resistor R1. There will therefore be a change from the previous value at the two inputs of operational amplifier OP3 and hence a change in signal will be generated at the output of operational amplifier OP3.
Circuit part 22 is a timer circuit which, provides a time interval of for example fifteen to thirty seconds to permit of a user of the alarm device to exit the protected area in which circumcstances the sensed voltage may well change but will not cause operation of the alarm unless some change is detected after the time delay period. The exit timing circuit 22 may comprise any suitable circuit and can conveniently comprise a microchip purpose built for such use.
The alarm system is now active and, if a voltage change is sensed in the vehicle electrical circuit, for example by an intruder opening a door thus causing operation of the courtesy light switch, or alternatively, for example by disconnection of the vehicle battery, then the voltage sensing circuit 21 will detect such a change in voltage and cause a signal to be generated to the output operational amplifier
OP3 which activates the alarm signal generating circuit 23.
When the alarm generating signal circuit 23 is activated an entry delay timer circuit 24 is also activated and, if the key 17 is not replaced in the socket 16 within a predetermined entry time, then the entry delay circuit 24 will cause operation of transistors TR4 and TR6 thus connecting siren S1 to the vehicle voltage supply thus sounding the alarm. If the plug 17 is replaced in the socket 16 before the entry time interval, then the alarm system is disabled and returns to its passive state ready for reactivation. If, after entry to the vehicle and within the timed entry period before the siren Si has sounded, an attempt is made to disable the -alarm by removing the plug 13 from the socket 14.
The sensing circuit senses a voltage drop and, since the circuit will still be powered by its battery 30, normal operation will take place. After a predetermined delay period, the relay coil RL2 will be activated which in turn closes relay contact RLC, conriecting the battery 30 to the siren Si thus providing an audible alarm signal.
Referring now to Fig. 3, the circuit once again comprises an "electronic switch" and comprises a jack plug socket 36, and a "key" 37 comprising a jack plug 38 having an electrical circuit 39 connected thereto.
Integrated circuits IC, and IC2 detect the presence of the "key" 37 in the socket 36 and if the plug 38 is withdrawn from the socket 36 then the output of integrated circuit
IC2 changes and an output signal is produced which, after a predetermined time delay, produces an input signal to integrated circuit IC3.
The aforesaid time delay is necessary to enable someone arming the circuit by removing the plug 38 from the socket 36, when the device is in use in the vehicle, to leave the vehicle and close the doors thereof. The time delay, hereinafter referred to as the "exit time delay", is governed by the relative values of capacitor C4 and resistor R4.
On removal of the "key" 37, the alarm circuit is "armed" and, once the signal has been sent to IC3 its output signal will change setting the integrated circuit iC4 in a receptive condition. Integrated circuit IC4 has one of its inputs connected across the supply line in the power supplied to the vehicle electrical system and has such input connected between capacitor
C5 and resistor R5. If integrated- circuit IC4 detects a drop in this voltage, for example due to a door opening and a "courtesy light" of the vehicle being switched on, or any other event which uses power from the vehicle electrical supply system, then its output changes and a signal will be sent to integrated circuit
IC5.
There is a delay in sending of the signal to integrated circuit Ices, which delay is caused by resistance capacitor network comprising variable resistor VR6 and capacitor C6, such delay network providing for an entry time to the vehicle, hereinafter referred to as the "entry time delay".
Such an "entry time delay" is necessary so that the authorised user of the vehicle may enter the vehicle without the alarm system being activated.
The "entry time delay" may be somewhere between ten and fifteen seconds or as required by the user. The presence of a variable resistor VR6 enables easy adjustment of the time delay required.
The presence of the variable resistor VR6 permits a user of the system to initially provide a fairly lengthy entry time delay and after use of the system when the user becomes more skilled, such user may then decrease the length of the entry time delay.
It will be realised that where the alarm is energised or de-energised outside the vehicle, for example by a transmitted signal, provision of an entry time delay is not necessary since the alarm system may be dis-armed before the vehicle is entered and hence before any changes in the vehicle electrical system voltage takes place.
It the vehicle is entered by an authorised person, then such person will replace the "electrical" key in the socket 36 and the circuit will then return to a non-active state.
If on the other hand the vehicle has been entered by an unauthorised person who does not have a key, then after the aforesaid "entry time delay", IC5 will generate a signal to switch on field effect transistor TR6 thus connecting siren S2 across the vehicle supply line thus sounding an alarm signal.
If the vehicle supply is disconnected by an intruder for example, in order to try and silence the alarm signal of the siren S2, a backup battery CN3 will immediately take over energisation of the siren S2.
The circuitry for switching in the battery CN3 will now be described. When integrated circuit
IC4 has produced an output signal and, after the entry time delay, a signal will be transmitted to transistor TR7 switching on the transistor and thus energising relay coil RL3.
Energisation of relay coil RL3 closes contact RL3 C1 thus connecting the battery CN3 in circuit across the supply line.
It is envisaged that the output voltage of battery CN3 will be slightly less than the voltage of the vehicle supply system, thus no power will be drawn from the battery which may be of the re-chargeable type, unless the vehicle power supply is disconnected.
A further advantage is gained by ensuring that the voltage output of the battery is slightly less than that of the normal vehicle electrical supply system since power will be supplied to the battery CN3 from the vehicle electrical supply system through diode D1 and resistor R8 at a predetermined rate ensuring that the battery is always in a good state of charge.
As a further precaution, it is envisaged that the siren may be sounded only for a predeter mined length of time and a further integrated circuit le, is provided which, in combination with resistor R7 and capacitor C7 will, after a predetermined time period dictated by the resistance capacitor network R7, C7 cause a signal to be sent from the output of integrated circuit IC, to the inputs of l(: and IC2 which has the same effect as the plug 38 being momentarily inserted into the socket 36, thus re-setting the alarm circuit causing field effect transistor TR, to turn off thus switching off siren S2.
The alarm system of the present invention by the provision of its internal backup power support ensures that any tampering of the alarm system once the alarm has been set causes the siren or other audible warning device to continue to sound.
Whereas'the system has been described above as having an internal siren, it is -envi- saged that transmitter means may be included in the circuit to transmit a signal to audible sounding means mounted elsewhere or other warning device, for example such other warming device may comprise an audio/visual indicating means mounted in a user's home or place of work.
The features disclosed in the foregoing description, or in the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed results, or the class or group of substances or compositions, is appropriate, may, separately or any combination of such features, be utilized for realising the invention in diverse forms thereof.
Claims (24)
1. An alarm system comprising in assembly a sensing means adapted to sense a predetermined event, alarm signal generating means responsive to the sensing of an event to generate an alarm signal, power supply means for energising said sensing means and said alarm signal generating means and "security" switch means for rendering said system operative or inoperative.
2. An alarm system according to Claim 1 wherein said sensing means, said alarm signal generating means, said power supply means and said security switch means are located in close proximity to each other.
3. An alarm system according to Claim 2 wherein said sensing means, said alarm signal generating means, said power supply means and said security switch means are positioned within an enclosure member of a form to provide a tamper-proof casing to prevent easy access to the inside of said enclosure.
4. An alarm system according to any one of the preceding claims wherein said sensing means comprises a voltage or current sensing circuit, said sensing circuit being capable of connection to an electrical circuit of a vehicle.
5. An alarm system according to Claim 4 wherein said system is provided with means whereby it may be readily connected to the electrical circuit provided in the vehicle.
6. An alarm system according to Claim 5 wherein said connection comprises a plug provided on said alarm system, the plug being adapted to fit in an electrically operated cigarette lighter provided on the vehicle.
7. An alarm system according to any one of the preceding claims wherein said alarm signal generating means further comprises an audio electrical transducer whereby said signal may be transformed from an electrical signal to an audio signal.
8. An alarm system according to Claim 7 wherein said audio electrical transducer comprises a siren.
9. An alarm system according to any one of the preceding claims wherein said security switch means comprises a key operated switch.
10. An alarm system according to any one of Claims 1 to 8 wherein said security switch means comprises a combination switch.
11. An alarm system according to any one of Claims 1 to 8 wherein said security switch means comprises an electronic switch operated by an electrical signal.
12. An alarm system according to any one of Claims 1 to 8 wherein said security switch means comprises an electrical circuit with predetermined characteristics and, to which circuit the alarm system responds when connected thereto to activate or deactivate the alarm system.
13. An alarm system according to Claim
12 wherein said electrical circuit comprises an electrically conductive path having a predetermined resistance, reluctance, or reactance, or combination of same.
14. An alarm system according to any one of the preceding claims wherein said system includes delay means whereby after activation of said alarm system said alarm system will not respond to the sensing of an event until the predetermined time period has elapsed.
15. An alarm system according to any one of the preceding claims wherein said alarm system includes further delay means whereby after the sensing of an event, said sensing means does not cause activation of said alarm signal generating means until a predetermined period of time has elapsed.
16. An alarm system according to any one of the preceding claims including audible signal generating means and circuit means whereby after the sensing of an event, said audible signal is sounded for a predetermined length of time.
17. An alarm system according to any one of the preceding claims wherein said alarm system is adapted for use in a vehicle and whereby means are provided to enable said alarm system to be powered by an electrical source of power normally associated with vehicles and wherein said system further includes means whereby if said source of power is disconnected from the alarm system, said power supply means will cause energisation of said alarm signal generating means.
18. An alarm system according to any one of the preceding claims wherein said sensing means senses the voltage in an electrical circuit provided in a vehicle and an alarm signal generating means is responsive to a drop in the voltage sensed by said sensing means to generate an alarm signal.
19. An alarm system according to any one of the preceding claims wherein said alarm signal generating means is connected to a visual alarm signal indicating device.
20. An alarm system according to Claim 19 wherein said visual alarm signal indicating device comprises lights normally provided on a vehicle.
21. An alarm system substantially as hereinbefore described with reference to and as illustrated in Figs. 1 and 2 of. the accompanying drawings.
22. An alarm system substantially as hereinbefore described with reference to and as illustrated in Figs. 1 and 3 of the accompanying drawings.
23. In combination an alarm system as claimed in any one of the preceding claims and a vehicle having an electrical supply system and wherein said alarm system is connected to the vehicle electrical supply circuit.
24. An alarm system including any novel feature or novel combination of features disclosed herein and/or shown in the accompanying drawings.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB8431694A GB2170633A (en) | 1984-12-14 | 1984-12-14 | Vehicle theft alarm |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB8431694A GB2170633A (en) | 1984-12-14 | 1984-12-14 | Vehicle theft alarm |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB8431694D0 GB8431694D0 (en) | 1985-01-30 |
| GB2170633A true GB2170633A (en) | 1986-08-06 |
Family
ID=10571238
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB8431694A Withdrawn GB2170633A (en) | 1984-12-14 | 1984-12-14 | Vehicle theft alarm |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2170633A (en) |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2198270A (en) * | 1986-12-06 | 1988-06-08 | Wilson Margaret | Car security system |
| US4884055A (en) * | 1986-12-03 | 1989-11-28 | Delta Elettronica S.P.A. | Antitheft system |
| FR2635396A1 (en) * | 1988-08-09 | 1990-02-16 | Texton | METHOD FOR AUTOMATICALLY RELEASING AN ALARM, IN PARTICULAR FOR A MOTOR VEHICLE AND SYSTEM FOR IMPLEMENTING SAID METHOD |
| GB2226671A (en) * | 1988-10-19 | 1990-07-04 | Hi Key Ltd | Vehicle intruder detecting apparatus |
| WO1993025414A2 (en) * | 1992-06-18 | 1993-12-23 | British Technology Group Limited | Security enabling and switching devices |
| US5307048A (en) * | 1992-12-18 | 1994-04-26 | Protect & Defend, Inc. | Vehicle security system including an anti-carjacking system |
| GB2309810A (en) * | 1996-01-31 | 1997-08-06 | Cannon Ltd | A warning indicator for use in a vehicle |
| WO2001049536A1 (en) * | 1999-12-30 | 2001-07-12 | Scania Cv Aktiebolag (Publ) | Alarm system for a motor vehicle |
| GB2447946A (en) * | 2007-03-29 | 2008-10-01 | Kelly John Speller | Vehicle alarm system |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1197584A (en) * | 1966-07-28 | 1970-07-08 | Gen Alarm Corp | Burglar Alarm Systems |
| GB1288635A (en) * | 1969-08-14 | 1972-09-13 | ||
| GB2029060A (en) * | 1978-08-26 | 1980-03-12 | Conquest Electronics Ltd | Improvements in or Relating to Vehicles with Alarms |
| GB2068158A (en) * | 1980-01-28 | 1981-08-05 | Welsh John | Intrusion alarm system for vehicles |
| GB2133192A (en) * | 1982-11-03 | 1984-07-18 | Alan Webb | Alarm unit |
| GB2138611A (en) * | 1983-02-16 | 1984-10-24 | H Ashworth | Alarm systems |
| GB2140950A (en) * | 1983-05-31 | 1984-12-05 | Robert Edward Pickles | Warning devices |
-
1984
- 1984-12-14 GB GB8431694A patent/GB2170633A/en not_active Withdrawn
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1197584A (en) * | 1966-07-28 | 1970-07-08 | Gen Alarm Corp | Burglar Alarm Systems |
| GB1288635A (en) * | 1969-08-14 | 1972-09-13 | ||
| GB2029060A (en) * | 1978-08-26 | 1980-03-12 | Conquest Electronics Ltd | Improvements in or Relating to Vehicles with Alarms |
| GB2068158A (en) * | 1980-01-28 | 1981-08-05 | Welsh John | Intrusion alarm system for vehicles |
| GB2133192A (en) * | 1982-11-03 | 1984-07-18 | Alan Webb | Alarm unit |
| GB2138611A (en) * | 1983-02-16 | 1984-10-24 | H Ashworth | Alarm systems |
| GB2140950A (en) * | 1983-05-31 | 1984-12-05 | Robert Edward Pickles | Warning devices |
Cited By (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4884055A (en) * | 1986-12-03 | 1989-11-28 | Delta Elettronica S.P.A. | Antitheft system |
| GB2198270A (en) * | 1986-12-06 | 1988-06-08 | Wilson Margaret | Car security system |
| FR2635396A1 (en) * | 1988-08-09 | 1990-02-16 | Texton | METHOD FOR AUTOMATICALLY RELEASING AN ALARM, IN PARTICULAR FOR A MOTOR VEHICLE AND SYSTEM FOR IMPLEMENTING SAID METHOD |
| EP0358544A2 (en) * | 1988-08-09 | 1990-03-14 | Sté TEXTON | Method and device for automatically activating the alarm system, in particular for an automobile |
| EP0358544A3 (en) * | 1988-08-09 | 1990-03-28 | Sté TEXTON | Method and device for automatically activating the alarm system, in particular for an automobile |
| GB2226671A (en) * | 1988-10-19 | 1990-07-04 | Hi Key Ltd | Vehicle intruder detecting apparatus |
| WO1993025414A3 (en) * | 1992-06-18 | 1995-01-26 | Andrew Jonathan Thomas Sansome | Security enabling and switching devices |
| WO1993025414A2 (en) * | 1992-06-18 | 1993-12-23 | British Technology Group Limited | Security enabling and switching devices |
| EP0742128A1 (en) * | 1992-06-18 | 1996-11-13 | Btg International Limited | Security enabling and switching devices |
| US5677663A (en) * | 1992-06-18 | 1997-10-14 | British Technology Group Limited | Security enabling and switching devices |
| AU684464B2 (en) * | 1992-06-18 | 1997-12-18 | British Technology Group Limited | Security enabling and switching devices |
| US5307048A (en) * | 1992-12-18 | 1994-04-26 | Protect & Defend, Inc. | Vehicle security system including an anti-carjacking system |
| GB2309810A (en) * | 1996-01-31 | 1997-08-06 | Cannon Ltd | A warning indicator for use in a vehicle |
| WO2001049536A1 (en) * | 1999-12-30 | 2001-07-12 | Scania Cv Aktiebolag (Publ) | Alarm system for a motor vehicle |
| US7046156B2 (en) | 1999-12-30 | 2006-05-16 | Scania Cv Ab (Publ) | Alarm system for a motor vehicle |
| GB2447946A (en) * | 2007-03-29 | 2008-10-01 | Kelly John Speller | Vehicle alarm system |
Also Published As
| Publication number | Publication date |
|---|---|
| GB8431694D0 (en) | 1985-01-30 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |