FR2474414A1 - INTRUSION ALARM ASSEMBLY FOR VEHICLES - Google Patents

Abstract

INTRUSION ALARM KIT FOR VEHICLES. THE CIRCUIT IS CHARACTERIZED IN THAT IT INCLUDES: A TRANSMITTER MEANS 40 SUITABLE TO BROADCAST AN ALARM SIGNAL AT HIGH FREQUENCY, ITS TRANSMITTER MEDIUM INCLUDING A MODULATOR MEDIUM 46 PROVIDING A LOW FREQUENCY FOR MODULATING THE HIGH FREQUENCY ALARM SIGNAL THE SAID LOW FREQUENCY; AND A CONTROL MEANS 25 SUITABLE TO SELECTIVELY TRIGGERING ITS TRANSMITTER MEANS IN THE EVENT OF AN UNAUTHORIZED INTRUSION, THESE CONTROL MEANS INCLUDING A VOLTAGE DETECTOR MEANS 26 SUITABLE TO DETECT A DROP IN THE VOLTAGE OF THE VEHICLE'S ELECTRIC CIRCUIT ONE OUTPUT SIGNALING THE SAID VOLTAGE DROP, A MEDIUM TIMER 30, 31, 34, 35 RECEIVING LEDIT OUTPUT SIGNAL FROM THE MEDIUM VOLTAGE DETECTOR 26 AND PROVIDING A TRANSMITTER TRIP SIGNAL AUDIT TRANSMITTER MEDIUM 40 AFTER A FIRST DELAY, AND A PRESELECTION DELAY COMMUTATION 36 SPECIFIC TO PROHIBIT TRANSMISSION AUDIT MEDIUM TRANSMITTER OF A SIGNAL FROM THE MEDIUM TIMER.

Description

1 2474414

  The present invention relates generally to a vehicle alarm assembly, and more particularly to an alarm assembly for detecting an unauthorized intrusion.

  in a vehicle and to determine the location of such a vehicle.

  cule. In recent times, thefts of vehicles such as boats,

  planes, recreational vehicles, trucks, and especially cars

  particular problems have reached alarming proportions. In the

  purpose of reversing this trend and defeating the temptation

  many devices have been devised to provide

  alarm or to put the vehicle out of order

  walking in case of unauthorized penetration into it.

  Those deterrents that provide an alarm signal use an acoustic alarm

  hoping to scare the thief in power and / or

  alarm clock radio. However, since such devices normally call for their supply to the electrical circuit

  of the vehicle, it is possible to quickly render them inoperable

  rants. Moreover, those of these devices that emit a signal

  high-frequency alarm require the construction of

  extended and expensive receiving buckets and / or transmitters-receivers

  telemetry transmitters to detect and locate a

alarm signal.

  Deterrent devices designed to put the vehicle

  the out of order condition, for example by cutting the ignition or fuel supply or locking the steering column, can also be neutralized by experienced thieves, can pocket unexpectedly

  a person authorized to operate the vehicle, and are

  unable to indicate to law enforcement officers the location of

  vehicle when it was successfully stolen. Some locking devices operate after a fixed time,

  which creates extremely dangerous situations, even fata-

  if an authorized person who has inadvertently failed to comply with the appropriate

  without warning a switch off of the ignition or the arrival of com-

  bumper or u locking of the steering column during the

effective operation of the vehicle.

  One of the aims of the present invention is therefore to provide an intrusion and location alarm system 24'744i4 for vehicles which is inexpensive and provides an alarm signal.

by transmitting a radio signal.

  Another object of the present invention is to propose a set of intrusion and vehicle-location alarms, as above, which implements a reception network of

pre-existing extended tear.

  Yet another object of the present invention is to

  set an intrusion alarm and location set for

  vehicles, as above, which includes a power supply of

  embedded independent transmitter so that any attempt to force the intrusion alarm device

triggering the transmitter.

  These and other objects and advantages of the invention over the prior art will be more fully apparent.

  the description given below as an example and

drawings that accompany it.

  Belon the invention, an alarm circuit for detecting

  an unauthorized intrusion into a vehicle involves a

  In general, a transmitter capable of broadcasting an ilar-

  radio, or high-frequency signal, the transmitter comprising

  a modulator providing a low frequency to the effect of

  the high-frequency alarm signal at the low frequency

  itself, and a command set that can trigger a selective

  the issuer in case of unauthorized intrusion. The control assembly comprises a voltage detector capable of detecting a drop in the voltage of the electric circuit of the vehicle and providing an output signal signaling such a voltage drop, a timer circuit receiving the output signal of the voltage detector and issuing an emitter signal to the transmitter after a first preselected delay,

  and a security switch to prohibit the transmission of

  signal from the timer circuit to the transmitter.

  An alarm set intended to detect an intrusion

  unauthorized in a vehicle and to locate the location of the vehicle

  of the invention comprises an alarm device of

  vehicle installed on the vehicle for the purpose of providing

  high-frequency alarm signal in case of unauthorized intrusion into the vehicle, the high-frequency alarm signal being at a distress frequency located in the frequency spectrum of the so-called public use band and being modulated at a frequency

  bass, and several tunable radio receivers on the frequency

  said distress signal, the modulation of the high frequency alarm signal providing a distinct and recognizable sound pattern to be distinguished by the receivers from reception intensity speech signals;

significantly stronger.

  In the accompanying drawings: FIG. 1 is a block diagram of an intrusion and location alarm system for vehicles according to the present invention;

  Fig 2 is a block diagram of part of the assembly

  intrusion alarm and location for vehicles of fig 1, adapted in particular to locate and display the

  position in a pre-selected geographical area of

  cules whose alarm device has been triggered;

  Fig. 3 is another detailed block diagram of the example

  an emitter-responder with a graphic grid represented by FIG. 2; and

  FIG. 4 is another detailed functional diagram of the e:

  example of an individual alarm device for vehicles

  presented in fig 1, which represents in a partial form-

  schematically a set with alarm control unit

and identification transmitter.

  FIG. 1 represents a complete set of intruder alarm and vehicle location according to the present invention, which is generally indicated by the numerical mark 10. The assembly 10 comprises a vehicle alarm device, one of which several are designated in the drawings by the numeral 11, and are installed as

  we will see it later in each individual vehicle to

  and three separate networks 12, 13 and 14 may be implemented alternately or simultaneously to identify the position of each vehicle whose device

  Vehicle alarm 11 was triggered.

  The network 12 uses as a detection system

  free and penetrating the very large number of

  radio stations; schematized in 15, operating in the public use band. As will be seen below, the vehicle alarm device 11 emits a high frequency signal

  (hereinafter referred to as RF signal) with audible frequency modulation

24'74414

  in case of unauthorized intrusion into the vehicle. For

  take advantage of this system as a pre-existing warning network -j-

  and economically, it is very advantageous to adopt for such frequency the distress frequency widely recognized as such of 2J4185 MEz of the public use band, commonly referred to as "channel 19." In this way, whenever a vehicle with triggered alarm device comes & proximity

  immediate reception of a public radio band receiver

  on channel 19, the alarm signal modulated at a frequency above

  dible can be heard. Since the majority of public radio band installations are stations themselves

  vehicles operating in vehicles, the probability of

  RF signal from a vehicle with a

  triggered alarm device is extremely strong.

  In order to identify specifically a

  signal issued by the vehicle alarm device 11 and

  ensure that this signal is easily distinguished

  among other signals whose reception intensity is likely to be many times higher than its own, it is very advantageous to modulate the BHF signal emitted

  by the vehicle alarm device 11. The form of modula-

  The simplest, yet most effective, technique found is to use a very low audible frequency of about 10 Hz. Of course, other forms of modulation are likely to

the implementation of the invention.

  In certain specialized applications, it may be advantageous to constitute a network 13 comprising detectors

  specialized mobile alarm systems 16 whose receivers are

  fixedly fixed to the HF emission frequency of the

  For example, vehicles used in police operations may be equipped with inexpensive receivers granted on channel 19. Such

  receivers can then fulfill the dual function of receiving

  distress signals of the public use band and

  reception of the alarm signal emitted by any

  11 individual vehicle alarm signal near the police vehicle, and allow police officers to immediately search for and possibly recover stolen vehicles in which is installed-a device

2474414

  vehicle alarm 11 being in the triggered state.

  In metropolitan areas with very large numbers

  many vehicles for a wide geographical range, one can

  In addition, it is preferable to establish a network 14 with

  The detectors 17 may be inexpensive receivers tuned to the channel 19 and mounted at preselected fixed locations throughout the geographical area having

of interest.

  As another example, local law enforcement authorities could set up specialized fixed alarm detectors 17 on telephone poles or other elements at appropriate intervals to ensure complete reception coverage throughout the entire area. jurisdictional area. Instead of providing receivers which provide an audible output signal as shown in FIG. 2, graphical grid transponder transmitters 20 can be provided providing a system alarm signal to be transmitted by dedicated telephone lines or by other means suitable for a centralization station to allow a bulletin board 21 to graphically display the relative geographical position of each transponder and to distinguish visually and / or

  acoustically those of the transponders 20 which receive

an HF alarm signal.

  As further shown in FIG. 3, an example

  The graphical grid transponder transmitter 20 may

  a conventional dedicated receiver 22 which is fixedly tuned to the channel 19 and whose detector provides an output signal to a conventional bandpass filter 23. The center frequency of the bandpass filter 23 is set to

  modulation frequency of 10 Hz in the present example.

  when receiving a modulated HF signal at 10 Hz, the bandpass filter 23 provides an output signal to a relay 24

  which delivers the system alarm signal mentioned above.

  As can be seen in FIG. 4, an individual vehicle alarm device 11 generally comprises an alarm control unit 25 and an identification or tracking transmitter 40. The alarm control unit 25 comprises a voltage drop detector 26, a power supply filter 28, an intrusion timer 30, an output timer 31, a push-button switch 32, an RS 33 flip-flop, a relay

  34, a relay contact 35 and a safety switch 36.

  The voltage drop detector 26, which is electrically-connected

  two terminals of the battery 27 of the vehicle, may be any of the many conventional detectors for monitoring the value of a voltage and providing a signal

  of output in case of exceeding a maximum permissible variation

  preselected value of the monitored voltage value.

  Although the negative terminal of the battery 27 of the vehicle is shown as connected to ground, and that one can

  in the following, to speak of "grounding" for the

  to establish with this marker, it should be emphasized that

  positive alarm 11 also lends itself to being associated with a vehicle whose electrical circuit is isolated from the mass or

is positive to ground.

  The voltage of the battery 27 of the vehicle is also received by a power supply filter 28 comprising a diode 29 and a capacitor 37. The anode of the diode 29 is connected to the positive terminal of the battery 27. The capacitor 37 is mounted between the negative terminal of the battery 27 and the cathode of the diode 29. The cathode of the diode 29 and the negative terminal of the battery 27 of the vehicle provide a filtered power source for the electrical components of the alarm device

of vehicle 11.

  The intrusion timer 30 receives the output signal

  voltage drop detector 26 and the power supply voltage

  filter supplied by the filter-feeder 28. the temperature

  intrusion porator 30 may be any conventional timer providing an output signal after a predetermined time delay from receipt of the output signal

  of the voltage drop detector 26. The output timer

  The tie 31 receives the output signal from the voltage drop detector 26 and is connected to one of the terminals of the switch. The exit timer 31 may also be any conventional timer.

  providing an exit signal after expiry of a pre-

  selected from the momentary closure of the interrup-

pushbutton 32.

  The EdgnaUX of s: ôrtie coming from the intrusion timer

2474414 I

  and the output timer 31 are respectively received by the reset and arming inputs of the conventional RS flip-flop 33. The signal provided by the Q output of the flip-flop 33 and the positive filtered supply voltage supplied by the cathode of the diode 29 are applied to opposite ends of the winding (not shown) of the relay 34 so that upon receipt of an appropriate logic level signal

  from the flip-flop 33, the normal relay contact

  Opened 35 closes and remains closed until latch 33 is reset by intrusion timer 30. Security switch 36 has several groups.

  each of which can be pre-set to a different number.

  its input terminal is only connected to the output terminal when all groups are

  on their respective preset number. The selector switch

  The security 36 may be provided with any number of groups providing the desired degree of protection by providing too many codes to permit rapid identification of the operating combination. In most applications, the security switch 36 may be a four-digit knurled ring switch as shown in FIG.

fig.3-

  The safety switch 36 is connected to ground by

  its input terminal, the mobile contact of the ad-

  The output terminal is connected to the terminal of the push switch 32 opposite that connected to the output timer 31, and is connected via its output terminal to one of the sides of the relay contact 35. relay contact 35 which is opposite to that connected to safety switch 36 is connected to ground. The signal appearing across the relay contact 35 is the output signal of the control unit

  25, and provides the triggering order of the transmitter

identification number 40.

  The identification transmitter 40 comprises a supply trigger 41, a very low frequency modulator 46 and a high frequency oscillator 47 to winding. The supply trip device 41 comprises batteries 42, 43, a resistor 44 and a field effect transistor 45. The positive terminal of the battery 42 is connected to the side of the relay contact 8, opposite to the one connected to it. to the mass. LIa negative terminal of

  the battery 42 is connected to the control electrode of the transistor

  Field effect tor 45. Resistance 44 is mounted between

  the control electrode and the source of the transistor 45. The battery 43 is connected by its positive terminal to the source of the transistor and by its negative terminal to the side of the relay contact 35

which is connected to the mass.

  The low frequency modulator 46 can be any

  conventional modulator to modulate the power supply of the os-

  high frequency oscillator 47 at low acoustic frequency.

  selected. The modulator 46 is connected to the drain of the field effect transistor 45 and to the negative terminal of the battery 43,

  and it itself provides a modulated output signal to the oscilla-

  47. For the reasons explained above, the high frequency oscillator 47 is preferably tuned to

  to resonate at approximately 27.185 MHz, radio frequency of

Braid of the band of public use.

  Now that the arrangement of an exemplary vehicle alarm device 11 has been described in detail, it is possible to expose

  its operation. It will be easier to understand the function

  of the vehicle alarm device 11 noting everything

  first that the vehicle alarm device is triggered

  by any variation in the voltage of the electrical circuit of the

  vehicle exceeding a preselected maximum.

  Since in virtually all cases of penetration into the vehicle or attempt to establish the ignition contact,

  such a voltage variation of the electrical circuit of the vehicle

  This will occur due to voltage drops across the light bulbs, starter, etc. such an alarm detection means is extremely reliable. However, as an authorized person will also produce alarm trip voltage drops when entering the vehicle and into-in

  outgoing, when the alarm device 11 is mounted inside the

  In order to reinforce the security of the vehicle, means must be provided to temporarily disable the identification transmitter 40 while the authorized person enters the car and permanently disarms the alarm device. 11, as she gets out of the car after arming the device. In conjunction with the circuits associated with them, the intrusion timer 30 and the output timer 31 fill

  respectively this function when entering and leaving.

  When the vehicle is in normal use by an authorized person, the heater switch is set to its preset PIN. On tauare 4, the alignment of the moving contact of each of the groups, considered by going from left to right, respectively to the right of the third, seventh, ninth and third positions of

  contact from the top, has the effect of

  Thus, the batteries 42 and 43 are in series. The resulting voltage between the control electrode and the source has the effect of blocking the field effect transistor 45, which prevents any supply of the low frequency modulator Ei A46 and the high frequency oscillator 47. In essence, the

  security switch 36 has rendered the iden-

  40 by shorting its drivers.

  Tree. The setting of the security switch 36 on its confidential code can be called "disarming" of the device

O vehicle alarm 11.

  When the authorized person wants to leave the vehicle and activate the vehicle alarm device 11, it suffices to press the push-button switch 32, which momentarily links the output timer 31 to the mass by putting the in operation. The output timer 31 immediately delivers a persistent output signal that arms the flip-flop 33. The output Q of the latter then changes.

  of state, which has the effect of exciting relay 34 and of

  sea relay contact normally open 35. As long as the -

  relay contact 35 remains closed, the identification transmitter

  40 is still rendered inoperative because its input leads are short-circuited. Thanks to a preset of the time constant of the output timer to a value

  sufficiently long, for example 120 seconds, to allow

  * to the person authorized to leave the vehicle, no

  voltage drop caused by the authorized person in

  the vehicle will not trigger the identification transmitter 40. As soon as it releases the push-button switch 32, the

  authorized person to replace the security switch at random

  36 on a code other than the pre-established confidential code,

910 2474414 I

  which carries out the "arming" of the vehicle alarm device

the individual 11.

  If & as a result of this the electric circuit of the vehicle

  come for any reason to experience a fall in

  At the expiration of a preselected delay, the intrusion timer 30 transmits an output signal that resets the latch 33. The Q output of the latter then returns to its original state, causing the relay 34 to de-energize.

  and the reopening of the relay contact 35. Thanks to a pre-

  setting the intrusion timer to a sufficiently long time constant, for example 60 seconds, to allow the authorized person time to enter the vehicle and disarm the alarm device 11 by acting on the security switch 36, no voltage drop caused by it in retreating into the vehicle will trigger the identification transmitter 40. Of course, an unauthorized person does not know the preset PIN

  will be unable to stop the activation of the

  40. In addition, in case of cross-section of

  conductors terminating at the identification transmitter 40, the

  power release 41, which has its own power supply

  tation, will immediately trigger the low frequency modulator 46 and the high frequency oscillator 47? in

  causing the emission of a modulated high-frequency signal

  allowing unauthorized penetration.

  Ea view to make the intrusion alarm and vehicle location set 10 as resistant as possible to

  attempts at maladjustment, it was found that it was very

  tagging all the components of the transmitter 40 in an envelope in the form of a thin wafer or label, which can be sandwiched between

  the layers of the windscreen of the vehicles during the

  tion. Additional incorporation of a charge winding

  in the EF 47 oscillator makes it unnecessary to use one

  external tenne, which allows the whole 10 to pass even more unnoticed. It has also been found that such a configuration leads to the establishment of a loose coupling of the RF signal with the cavity of the windshield itself, many of which have a natural resonance around 30 MEz, which provides a gain of signal

11 2474414

  additional. The identification transmitter 40 may be embodied as a low power output device, both so as not to be required to be licensed under the official telecommunications regulations and to increase the longevity of the device. battery operation

  - 42 and 43, which constitute the independent power supply of the

  identification issuer 40. Consideration of the

  identification transmitter 40 and the brief

  of its possible periods of operation,

  Terrains 42 and 43 formed by conventional alkaline batteries are capable of providing a useful operating life of about the same order as that of the vehicle. If desired, however, batteries 42 and 43 of the rechargeable type can be adopted by magnetic coupling, which allows them to be recharged inside the identification transmitter.

  without establishing a physical link with it.

  Since the present invention is capable of receiving many modifications and variations of detail, a certain number of which have been expressly mentioned above, it should be understood that all the arrangements described throughout this specification or represented in the drawings annexed are to be interpreted in an illustrative sense

  but not limiting. It is therefore obvious that a device

  in accordance with the basic provisions of this

  vention, and equivalent thereto, is able to reach

  bts of the present invention and to improve

  their substantially the technique of alarm devices de-

  detecting unauthorized penetration in vehicles

  and to identify the position of these.

Claims (9)

  1.- Alarm circuit for detecting an unauthorized intrusion into a vehicle, characterized in that it comprises: transmitter means (40) adapted to broadcast a high frequency alarm signal, said transmitter means comprising a modulator means (46) providing a low frequency for modulating said high frequency / alarm signal at said low frequency; and   control means (25) for selectively triggering the   said transmitter means during an unauthorized intrusion, said control means including a voltage detector means (26)   to detect a drop in the voltage of the electrical circuit.   the vehicle and to provide an exit signal signaling the-   said voltage drop, a timer means (30, 31, 34, 35)   receiving said output signal from said voltage detecting means   (26) and providing a transmitter trigger signal   mean issuer audit (40) after a first preselection   and switching means (36) to prohibit   mission means audit transmitter of a signal from said average timer.   2. Alarm circuit according to claim 1, characterized   in that said timer means (30, 31, 34, 35),   carries a first timer (30) receiving the output signal   said voltage detector means (26) and providing an output signal after said first preselected delay, and a second timer (31) selectively triggerable for   provide an output signal after a second preselected tioned.   3. Alarm circuit according to claim 2, characterized   in that said timer means (30, 31, 34, 35) comprises   further carries a relay means (34, 35) provided with a contact (35) whose closing state controls the tripping of said   transmitter means (40), said output signal of said first time   porator (30) and said output signal of said second time   porator (31) controlling the operation of said relay (34) so that said transmitter means (40) is triggered   during an unauthorized intrusion into the vehicle.   4.- Alarm circuit according to one of claims 1 and   3, characterized in that said transmitter means (40) further comprises supplying means (41) receiving said trigger output signal of said timer means 2474414 i (30, 31, 34, 35) by conductive means and triggering said modulator means (46) upon receipt of said output signal from   tripping, said triggering means (41) for feeding   further carrying an autonomous power supply means (42, 43) so that in case of breakage of said conductive means, said means   Alignment trigger triggers said modulator means.   5. Alarm circuit according to claim 4, characterized   it further comprises oscillator means (47) to   radio frequency receiving said very low frequency of said   yen modulator (46) and mixing it with a frequency   High frequency alarm carrier, -   said high frequency oscillator means (47) having a winding means capable of radiating   said high frequency alarm signal.   6. Alarm circuit according to claim 5, characterized   in that said transmitter means (40) is contained in a   speaker installed between the windshield layers of the vehicle ,.   said winding means establishing an electromagnetic coupling   lick of said high frequency alarm signal with the   said windshield for greater resonance in it.   7.- Alarm assembly for detecting an unauthorized intrusion into a vehicle and the location of the vehicle, characterized in that it comprises: a vehicle alarm device (11) installed on the vehicle to the effect to issue a   high-frequency alarm signal during the unauthorized intrusion   in the vehicle, said high frequency alarm signal   this being transmitted on a frequency of distress of the frequency spectrum   of the public use band and being modulated at a rate of   low quence; and a plurality of public service band radio receivers (15, 16, 17, 22) tunable to said frequency of   distress, said modulation of said high frequency alarm signal   quence producing a distinct sound pattern and recognizing   able to be distinguished by the said receptors   mid tone signals modulated by speech at intensity of substantially stronger reception.   8.- Alarm assembly for detecting an unauthorized intrusion into a vehicle and the location of the vehicle, characterized in that it comprises: a vehicle alarm device (11) installed on the vehicle to the effect to emit a high frequency warning signal during a voltage drop 2474414 1   of the vehicle electrical circuit due to unauthorized intrusion into the vehicle, said high frequency alarm signal being   transmitted on a distress frequency and being modulated at a frequency   low quence; and several receivers (15, 16, 17, 22)   on said distress frequency, said modulation of   said high frequency alarm signal producing a configura-   distinct and recognizable sound soundness to be distinguished   driven by said receivers among modulated sound signals   speech with a substantial reception intensity stronger.   9. Alarm assembly according to one of claims 7   and 8, characterized in that said receivers are fixedly tuned to said distress frequency and are permanently mounted at fixed geographical locations in an area to be monitored, and in that it further comprises means for display (18) receiving notification of receipt   an alarm signal by each receiver and displaying topo-   graphically the location of such receptors in the said area to watch.   0, - Alarm assembly according to claim 9, characterized   in that said receivers are transmitters-responders   having a high frequency detecting means (22) providing an output signal, a bandpass filter means (23) receiving said output signal of said high frequency detecting means (22) and providing an output signal at the   receiving a high frequency signal having said   very low frequency modulation, and relay means (24)   receiving said output signal from said pass filter means   band (23) and providing a system alarm signal display medium.