FR2837764A1 - Electronic security system for protecting vehicle against theft, comprises authorization actions by legal driver which are memorized and whose absence at starting and door opening starts count down - Google Patents

Abstract

A legal driver performs authorization actions (21) which are memorized (11) and on starting (22) are checked (13). If authorization exists it is eliminated (14) and the system waits (15). Without authorization a countdown (17) commences which results in vehicle blockage (26). During normal use (23) door opening (24) without authorization reset reinitiates checking, count down and vehicle blocking. An Independent claim is also included for electronic equipment able to process authorization procedures and vehicle utilization events.

Description

legs (12) of a driver.

F

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  The present invention relates to a method of protection against theft with or without violence from a vehicle, for example a car or a motorcycle. The present invention also relates to a use of this

  method, and a device implementing this method.

  It is known to those skilled in the art of devices of different types, intended to prevent theft of a vehicle, and operating according to numerous

1 0 principles.

  Some of these devices work by preventing the vehicle from starting when there is no code or identification key, mechanical or electronic. These devices can however be circumvented by well-equipped thieves, in particular by successive testing of several probable and known methods, until the correct one is found. In addition, such methods of starting a stopped vehicle can easily go unnoticed in an unsuspecting environment, and often may not attract the attention of those around you or law enforcement, even when the

  vehicle is fitted with an audible signal such as a siren.

  However, these systems are becoming increasingly effective, and other types of theft are increasing, in particular with aggression from the driver. This type of theft can occur by assaulting the driver, for example when stopping the vehicle in an open area. The driver is then threatened or abused, and the attacker takes his place in the car with the engine running, and flees with it. This type of theft is often called "carjacking", from the English expression hijacking "used to describe a hijacking. A variant of this type of theft is also increasingly occurring, and is sometimes called" homejacking ". This involves tracking a target vehicle

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  home or garage, then break and enter

  violence to steal the keys to the vehicle and run away with it.

  A system developed to deal with this type of threat consists in declaring the theft to an organization which transmits a signal to the stolen vehicle via a satellite. This signal is received by the vehicle and activates either a satellite or radio location beacon, or the radiotelephone transmission of its geographical position, obtained by a GPS device.

  (for Giobal Positioning System ") incorporated in the vehicle.

  However, such a system has a number of drawbacks.

  Its technological complexity makes it a fairly expensive device, therefore not very affordable apart from owners of high or very high-end vehicles. In addition, the antenna which receives the signal in the vehicle is a visible element which can be destroyed or deactivated quite easily. Finally, such high-end vehicles are more and more often hidden immediately after theft. in an enclosed truck, which prevents this

antenna to receive the signal.

  Another system consists in using a modular telephone, for example GSM, to call a receiving device placed in the vehicle, and to shut down the engine or activate a blocking of the vehicle remotely. However, this type of system assumes that the owner is aware of the theft. and is therefore limited to cases of theft by assault. The theft of a parked vehicle, or by burglary of the home in the absence of the owner therefore largely defeats such protection. Indeed, the duration of one night or one day off is largely sufficient to put the vehicle out of range of GSM networks, or to deactivate the receiver in the vehicle. For comparison, for example, it is estimated that a stolen car is repainted on average six hours after the theft. The same drawbacks also apply to another system, described by US Pat. No. 6,323,762, which consists in manually arming an anti-theft system at the time of the attack, by a switch concealed in

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  the vehicle. The system then waits for all the doors to be closed then starts a timer which cuts the engine and transmits by radio the

  vehicle position, obtained by a GPS device incorporated in the vehicle.

  Another system, described in US Pat. No. 5,912,615, consists in triggering a timer when opening a door with the engine running. Once this timer has expired, the system waits for the brakes to be activated and the vehicle stopped to shut down the engine and trigger an electric shock on the driver's seat. This system however only concerns cases of aggression, and is only of little effectiveness in the case of a traditional theft, or by burglary with theft of keys ("home

jacking ").

  Another system consists in permanently communicating a radio transmitter carried by the driver with a receiver placed in the vehicle, the presence of this transmitter being necessary to allow the vehicle to start. However, such a radio transmitter has the drawback of being able to be disturbed by intense electromagnetic emissions, for example near certain relays or television transmitters. In addition, the power supply of such a transmitter poses autonomy problems, which are

  sources of cost or problems with electricity supply.

  One of the aims of the invention is to propose a low-cost method and device for protecting a vehicle against theft with or without violence or assault, which operates without waiting for the victim to have noticed the theft. while being discreet and robust enough to be difficult to detect

or quickly deactivate.

  This object is achieved by a method of protection against theft for a vehicle, implemented by means of processing electrical or electronic information, characterized in that it comprises the following steps: - at a variable moment in the process, detection of an authorization event, by authorization detection means, and

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  storage, by the processing means in storage means, of an authorization for use; - Detection, by means of detection of use, of a start of use of the vehicle and memorization of a state of the vehicle as being in use, followed by a test of the presence or not of a authorization stored in the storage means; - in the case of a start of use without memorized authorization, triggering of a time count, called alert count; - in the case of a start of use with the presence of a memorized authorization, deletion of this authorization and waiting for events; - while the vehicle is in use, detection of an alert event and triggering of a time count, called an alert count; - at the end of the flight countdown, launch of a flight situation procedure. According to one feature, the method further comprises the following steps: - detection of an authorization event during an alert count; - cancellation of this alert count; According to a particular feature, the method further comprises a step of storing a permanent authorization, this permanent authorization preventing the triggering of an alert count on the subsequent occurrence of any number of alert events, and until canceled

of this permanent authorization.

  According to one feature, the state of use of the vehicle is determined by the operation or the engine and possibly a start of movement of the vehicle, at least one alert event consisting of an opening.

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  access to the vehicle, or the closure of such access, or the detection of a departure of the driver out of the vehicle, or the detection of a distance for a period greater than a determined period of a transmitting object or transponder carried by the driver, or the voluntary triggering of a signal from the vehicle or at a distance, or the crossing by an object or a person of a determined region surrounding the vehicle, or a

  combination of several of these events.

  According to a particular feature, at least one authorization event is constituted by an action on an electrical or electronic contactor by the driver or a passenger of the vehicle, or by the maneuver of a combination of several commands normally used for operation or use of the vehicle, or by establishing an electrical connection passing through the human body between several elements constituting detection means and communicating with the processing means, or

  by a combination of such actions.

  According to a particular feature, the flight situation procedure is executed immediately after the alert countdown, and includes the activation of engine starting prohibition means, or the permanent or repeated activation of engine cut-off means. engine or means for degrading engine operation, or activating light or sound signals, or activating an exchange of electronic information with a receiver device external to the vehicle by radio or telephone transmission, or a

combination of such actions.

  According to a particular feature, the alert countdown is triggered or

  takes place without being reported to the driver.

  According to one feature, the method is applied to theft protection. during legitimate use, of a motorized car or two-wheeled motor vehicle and comprises the following stages: - before starting the engine or setting the vehicle into motion, or during the alert count triggered by this

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  start, execution by a legitimate driver of the actions constituting an authorization event; - normal use of the vehicle by the legitimate driver; - during engine operation, after taking control of the vehicle by an illegitimate driver, call by the legitimate driver of a radio or telephone receiver device included in the vehicle, and transmission of a signal triggering a countdown alert or directly trigger the flight situation procedure; use of normal appearance of the vehicle during the alert count; - at the end of this alert count, triggering of the flight situation procedure. Another object of the invention is to propose a device putting in

_ such a process.

  This object is achieved by a theft protection device for a vehicle, comprising means for processing electronic or computer information, characterized in that these processing means comprise means for memorizing information representing an authorization for use. and a state of use of the vehicle, and communicate with means for detecting the state of use of the vehicle, means for detecting at least one authorization event, means for detecting at least one event alert, time counting means providing at least one timer of a fixed duration, and means for implementing a flight situation procedure. the processing means triggering a countdown of time, called an alert countdown, in the event of use of the vehicle in the absence of a memorized use authorization, then executing a

  flight situation procedure at the end of this time countdown.

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  According to a particular feature, the means for detecting an authorization event comprise an electrical circuit detecting the communication of an element of the vehicle or of the device with the mass of the vehicle, by electrical conduction through an electrical circuit or through the body of the driver or passenger of the vehicle. According to one feature, the means for detecting an alert event comprise an electrical circuit reacting to the opening or closing of a vehicle access, or a device detecting access to the interior of the vehicle by crossing a '' a region determines the space surrounding the vehicle, or a device for detecting the presence near the vehicle of a passive transponder or a radio transmitter carried by the driver

  legitimate, or a combination of these events.

  According to a particular feature, the means for detecting an alert event comprises a device receiving a radio signal, or a call

  telephone, or a signal transmitted by a telephone call.

  According to a particular feature, at the end of the alert count, the processing means execute a flight situation procedure by repeatedly actuating one or more audible and light alarms, or by interrupting the passage of at least one signal or electric current necessary for the normal operation of the engine, or by communicating to the engine information commanding a complete or repeated stop or a drop in performance, or by activating means to prohibit restarting of the

  engine or vehicle after stopping, or by a combination of these actions.

  According to one feature, the device comprises means for deactivating the device, these means possibly comprising either an electrical circuit permanently ensuring certain functions modified by the flight situation procedure. or means for storing a permanent authorization in the memorization means, memorizing such a permanent authorization preventing the implementation or the initiation of the flight situation procedure.

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  The invention, with its characteristics and advantages, will emerge more

  clearly on reading the description made with reference to the accompanying drawings

  in which: FIG. 1 represents a flowchart of the use of the vehicle and of the operation of the method according to the invention during this use, in the case of theft by aggression during use of the vehicle; FIG. 2 represents a flow diagram of the use of the vehicle and of the operation of the method according to the invention during this use, in the case of a start before authorization, then of an assault theft during use , in the absence of automatic detection of an alert event; - Figure 3 shows an electrical diagram of a device according

  the invention in one of its embodiments.

  The operation of the present invention makes it possible to offer protection against theft by aggression of the driver during normal use of a vehicle, but also offers protection against theft of a vehicle

  parked, with or without use of vehicle keys.

  It is a particularly advantageous feature of the invention to allow these two possibilities from the same process or device. In the case of a parked vehicle, the invention can for example be used in addition to an alarm or start-up prohibition device. In fact, if a thief manages to deactivate the start prohibition system, ie discreet operation of the invention makes it possible for this thief to believe that he has succeeded in his operation and is content to try to get in with the vehicle without seeking other protection systems. The method according to the invention then makes it possible to create one or more additional obstacles for the thief, by blocking the vehicle when he no longer expects it, and in a place where he will not be able to

necessarily act as it pleases.

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  The protection method according to the invention is implemented by means of processing electrical or electronic or computer information, installed in whole or in part in the vehicle, and comprising or communicating with storage means for this information. These processing means can take the form of an electronic box operating, for example, from logic circuits or using a microcontroller. These processing means communicate with various detection means capable of recognizing certain events occurring during the operation or use of the vehicle to be protected. They are also connected to means of action or control capable

  influence the operation of different parts of the vehicle.

  Examples of operation according to one embodiment are

illustrated in Figures 1 and 2.

  Within the framework of the method according to the invention, the normal use of the protected vehicle operates according to a procedure consisting in allowing a legitimate driver to record within memory means the fact

  that he is authorized to use this vehicle.

  For this, the driver performs a so-called authorization action, or a specific combination of several actions, which will be recognized as proof of legitimacy by authorization detection means. The fact of carrying out these authorization actions is then considered by the means of

  treated as an event, said authorization event.

  In the operating example illustrated in FIG. 1, the legitimate driver begins by carrying out the authorization actions (21) which make him recognize it as such. and are recognized by the processing means as an authorization event. When this authorization event is detected, the processing means store (11) an authorization for use in the storage means. Typically in normal operation, the occurrence of an authorization event triggers the storage of an authorization valid only once. In certain

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  variants, an authorization event, identical or different, can be provided to result in the storage of a plurality of authorizations, each

valid only once.

  After these authorization actions (21), the driver starts (22) the vehicle engine, for example after deactivating another anti-theft system operating by starting prohibition, independently of the present process. Use detection means then signal this starting of the engine to the processing means, which recognize this starting

  as a start of use (12) of the vehicle.

  At each start of use of the vehicle, the processing means carry out one or more tests (13) of the storage means, to find out

  if a user authorization has been previously stored.

  If such an authorization is found, the processing means store the erasure of this authorization, which arms the system and puts it on hold (15) for a future alert event (16). In the case where several authorizations are stored, the processing means decrement the

  number of available authorizations of a determined number.

  The legitimate driver can then use the vehicle for all

  displacement, according to normal use (23).

  When an alert event occurs while the vehicle is in use, such as the opening of a door (24) while the engine is running, this event is detected by alert detection means and

  communicated to the means of treatment.

  When they receive an alert event, the processing means perform one or more tests (13) of the storage means, to find out whether an authorization for use has been previously stored. If such authorization is found, the processing means memorize the erasure of this authorization, which rearms the system and puts it back on hold (15) by a

future alert event (16).

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  If no authorization is found during these tests (13), the processing means trigger (17) a time count, called an alert count, by time count means. During this alert countdown, the vehicle continues to operate in an apparently normal manner. Alternatively, the operation of this alert count can also be indicated by any signal, for example to avoid a driver

  legitimate to be embarrassed if he has only forgotten to identify himself.

  Thus, if the legitimate driver is the victim of an assault during normal use of the vehicle, for example during a stop in traffic, the thief has time to take control of the vehicle and to flee with it for the duration of the alert count (17). If the operation of the alert count is sufficiently discreet or harmless, the thief therefore believes that he has done everything necessary to ensure the immediate use of the vehicle. There is therefore no reason to be interested in the driver any longer, nor to seek to deactivate the

  process according to the invention, since he does not see the existence of it.

  When this alert count arrives at the end of a determined hardness, for example of the order of one to three minutes, the processing means trigger and execute (18) a so-called flight situation procedure. This procedure may include one or more actions controlled by the processing means, and serving to stop or hinder the illegitimate use of the

  vehicle and induce the thief to abandon the vehicle.

  This flight situation procedure may include stopping the engine, complete or by short and repeated interruptions, or degrading the operation of the engine or the rest of the vehicle. The vehicle then becomes

  unusable or difficult to use, and therefore difficult to move and camouflage.

  Depending on the applications, and in particular if local regulations prohibit stopping the engine while the vehicle is moving, the processing means can also immediately activate means for preventing the engine from starting. Once activated, these prohibition means can then prevent a restart of the engine after stopping,

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  or the engagement of a report in the case of an automatic gearbox. The processing means can also trigger a process which will shut off the engine automatically when the vehicle slows down.

  below a specific speed.

  This flight situation procedure may also include switching on various accessories of the vehicle, such as hazard lights, lights or signaling, or audible warning. Such signals can then allow on the one hand to destabilize the thief in his search for discretion, and on the other hand to let the immediate entourage know that the vehicle

  as is in an abnormal situation.

  This flight situation procedure can also include actions intended to locate the vehicle or alert the owner or surveillance services. These actions can then include the transmission of signals, by radio transmission or by telephone transmission. Such a transmission can also be used by external receivers to detect the position of the vehicle themselves, or to transmit to them data representing the position of the vehicle recorded by a system integrated into the vehicle, for example a GPS device (for "Global Position

System ").

  During normal use, it can of course happen to carry out actions corresponding to an alert event, for example opening a door to lower a passenger. When an alert event is triggered by an action which does not justify the execution of the flight situation procedure. the legitimate driver then has the possibility of interrupting the alert count (17) by carrying out (27; FIG. 2) the authorization actions. These actions will then be recognized as an end of alert (19; figure 2), which will

  interrupt the time countdown (17) and put the system back on hold (15).

  Alternatively, the driver can also perform these authorization actions (27) before the unmotivated alert event. These authorization actions will then store an authorization, which will be taken into account

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  during the next alert event. Thus, opening the door will not trigger an alert count, and the system will be armed again (15)

for further use.

  In the case where a driver begins (11) the use of the vehicle before carrying out (12) the authorization actions, as illustrated in FIG. 2, the processing means will not find authorization memorized when they test ( 13) the storage means. They will then trigger (17) a

  alert count similar to an alert event (16).

  If this beginning of use (11) is the result of a legitimate driver, it will then suffice for him to cancel this alert count (17) by carrying out the authorization actions (27; FIG. 2) after starting, to be able to continue normal use (28) with the armed and waiting process (15) for an alert event. If this start of use (11) is the result of a driver not knowing the authorization actions to be carried out, the processing means will then execute this alert count (17) then the situation procedure (18) theft in the same way as for theft (25, 31) committed during normal use (23). Thus, the method according to the invention makes it possible to thwart or hinder

  theft even if committed in the absence of a legitimate driver.

  In the event that the theft situation procedure includes a call from the owner of the vehicle by radio or telephone transmission, he will then be warned of the theft and may take the appropriate measures, for example to report the theft or search for the vehicle. The thief will therefore not have additional time to camouflage or transport the stolen vehicle, which is the case

  with a system that activates only when the theft is detected.

  In the case where the flight procedure includes a location or a signal transmission, it should also be noted that the automatic triggering of this flight situation procedure makes it possible to carry out this transmission immediately after the flight. Such a transmission is therefore less likely to be hampered by the camouflage of the vehicle in a room or a

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  truck closed, or to be prevented by the destruction of the transmission antenna. Thus, the method according to the invention also offers protection against the theft of a parked vehicle, or constitutes an improvement which can be complementary to conventional systems by prohibiting starting. During normal use (28), it may happen that the vehicle is stolen without the alert detection means communicating an alert event to the processing means. Such a situation can for example be the case for a discoverable car if the door is not opened. It can also be a motorcycle or a two-wheeler

  motorized without automatic alert detection means.

  In a variant, the method then comprises a step of voluntary triggering of an alert event, for example by the legitimate driver after an assault. By radio or telephone transmission means, for example a portable transmitter or a modular telephone, this legitimate driver then transmits a signal to reception means

  included in the vehicle and communicating with the processing means.

  On receipt of such a signal, the processing means will then execute an alert count (17) then a flight situation procedure (18). in the same way as described above. In a variant, on reception of this signal, the processing means can also execute the flight situation procedure (18) directly, without waiting for the duration corresponding to the

call settlement.

  In a variant, the method according to the invention includes the possibility of carrying out a permanent authorization storage step. Such a step consists in storing in the storage means an authorization which will not be erased or decremented by the processing means after a

  test triggered by a start of use or an alert event.

  This permanent authorization then makes it possible to continuously disarm the protection process, for example in order to be able to entrust the vehicle

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  to a service provider without having to reveal the content of the authorization actions, for example a garage or a hotel valet. A non-permanent but valid authorization for a plurality of tests (13) can also be used in such cases. It is therefore sufficient that the number of authorizations stored is sufficient for the tasks entrusted to this provider, without allowing him to use the vehicle in an abusive manner. In a variant, the processing means can wait for the vehicle to start moving after the engine has started (22) to trigger the alert countdown, even in the presence of an authorization after starting. Similarly, the processing means can await the setting in motion of the vehicle after an alert event (16) to trigger the alert countdown (17), even in the presence of a

  authorization after the alert event.

  In a variant, the processing means can trigger an alert count of a different duration depending on the nature of the alert event that they receive. After opening a door, the flight situation procedure (18) can for example be triggered after thirty seconds if the door has been closed, or after two minutes if the door is

remained open.

  In the present description, the terms legitimate driver, or

  vehicle owner, generally apply to a person with knowledge of the procedures to be followed to use the vehicle, regardless of any express authorization from the legal owner of the vehicle. This knowledge of the procedures includes in particular the knowledge of the actions to be carried out to carry out an authorization event recognizable as such by the processing means implementing the method according to the invention. This knowledge may or may not coincide with knowledge of other procedures or identification codes necessary for

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  deactivate other anti-theft devices that can be installed in the same vehicle. Thus, a so-called legitimate person who knows the authorization procedure used in the method according to the invention may very well be present in the vehicle only as a passenger, possibly for only part of the vehicle's use time. It is possible for such a legitimate person to carry out authorization actions by themselves, without

  inform the driver, especially if these actions appear harmless.

  In the case where the owner of the vehicle lets a potential buyer of the vehicle drive, it is thus possible for him to carry out these actions discreetly, for example if these include the activation of the radio associated with a contact of the hand on a metal part of the dashboard or the car radio console. If the vehicle is not sold, this authorization procedure will therefore remain secret. If the potential buyer tries to appropriate the vehicle without the consent of the legitimate person, the process according to the invention will then be implemented to thwart or hinder such an attempt to

vehicle theft.

  In the same spirit, the possession of the ignition keys of the vehicle is not sufficient to constitute a legitimate person within the meaning of the process according to the invention, any more than the possession of codes or mechanical keys or

  electronics deactivating other anti-theft systems present on the vehicle.

  This characteristic allows the method according to the invention to be able to be implemented in particular in the case of theft with assault or hostage taking, as in the case of "homejacking". The method according to the invention can then be used for the protection of a vehicle, in particular a motorized car or two-wheeler, by carrying out in this vehicle the installation of a device implementing this process, in

  particular according to one of the following uses.

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  In the event of an attempted theft of the parked vehicle or during an assault at home, once the thief has successfully started, or even

  after setting the vehicle in motion, the alert countdown is triggered.

  The thief can then use the vehicle in an apparently normal manner during this alert count, which allows him to start moving away from the place of theft. At the end of the alert count, for example after a minute and a half, the flight situation procedure is triggered. The vehicle is then immobilized, or slows down sufficiently to be no longer usable, which encourages the thief to abandon it. Slowing down only the vehicle by degrading the operation of the engine, or by intermittent cuts, in particular makes it possible to keep usable certain functions depending on the engine, in particular safety functions such as power steering or assistance.

when braking.

  If the flight situation procedure so provides, the processing means then call a receiving station outside the vehicle, for example the owner's telephone, to inform it of the attempted theft and possibly of the position of the vehicle. A person in possession of this receiving station can then take the appropriate measures, for example warning the police, seeking to locate the vehicle, going to take back possession of the vehicle, or ordering other search or blocking measures.

internal or external to the vehicle.

  In the case of normal use, the legitimate driver begins by performing the authorization actions and starting the vehicle, in this order

or not.

  In the event of an attempted theft in use, the alert count will

  triggers on an alert event, for example the opening of a door.

  Thus, for theft by aggression, the opening of the door by the aggressor triggers the alert countdown, possibly shortened by the closing of

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  that same door. Once this alert count has been completed, the aggressor or the assaulted driver has had some time to move away when the procedure

  flight situation is executed as described above.

  Similarly, for a theft by breach of trust or when the driver has left the vehicle leaving the keys with the vehicle, the alert countdown is triggered when the door is opened, which means that the thief does not have only a short time to flee before the initiation of this same flight situation procedure. In the case of an accessible vehicle without opening a sash, such as a discoverable car or a motorcycle or a motorized two-wheeler, the use of the method according to the invention can be done by an installation not comprising detection means. n automatic alert, ma is d es

  means for receiving a signal triggering an alert event.

  In the case of theft by assault or breach of trust or when the driver has left the vehicle leaving the keys with the vehicle, the legitimate driver can then use a radio transmitter or a telephone, his or another, to call these reception means and trigger the alert count or the flight situation procedure. All the means used in the process according to the invention can be produced in different forms, varying according to the

  applications or according to variants of the invention.

  Thus, the invention also proposes a device allowing the setting in

  _work of such a method, and an embodiment of which is illustrated in FIG. 3.

  In the embodiment described here, this device comprises a cas ^ 'tier (31) containing one or more electrical and electronic circuits, and communicating with the outside by connection means, for example two connection blocks (311, 312 ) o end two beams (313,

314) of electric wires.

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  The processing means implementing the method according to the invention are contained in the housing (31) and include a microcontroller in the form of an integrated circuit communicating with one or more storage circuits of the flash memory type, arranged on a circuit. printed and communicating with the outside by electrical connection

  direct or via relay.

  The whole of this box is supplied by a battery (50) belonging to the electric circuit of the vehicle, through one or more fuses (not shown). The embodiment described here uses a continuous 12V circuit with negative ground, but it is obvious that other electrical configurations

  are entirely possible without departing from the spirit of the invention.

  In the same way, the device is here described in an embodiment applied to a motor car, but can easily be transposed or adapted to a motorized two-wheeler, a motor boat, or

  other types of motor vehicles.

  The vehicle usage detection means comprise an electrical connection between the processing means and the start-up contactor (33), and by connection to a positive potential after the ignition key. These detection means can also receive a positive when the engine is running, for example by a connection with a diode at the output of the alternator,

  or on a corresponding logic contact within the electrical circuit.

  The authorization means comprise an electrical connection between the processing means and any contactor (43) controlling an accessory (430) or element of the vehicle, on the one hand. This contactor is chosen to deliver a positive potential when this accessory is activated, and can for example control the rear window defroster, or represent the command to deploy the antenna of a car radio. Setting this contactor to positive potential then constitutes a positive detection signal for the

means of authorization.

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  These authorization means also comprise an electrical connection between the processing means and a mass detection element which can be connected to the electrical ground of the vehicle. This mass detection element can be a contactor (44) controlling an accessory (440) by grounding. This mass detection element is then connected to the processing means so that setting this element to the potential of the vehicle ground triggers a mass detection signal within these authorization means. The conjunction of a positive detection signal and this mass detection signal within the authorization detection means then constitutes a use authorization event, recognized by these

  authorization detection means and communicated to the processing means.

  This mass detection element can also be an electrically conductive element and of harmless appearance, located in the passenger compartment of the vehicle, for example a fixing screw (45) or a metallic element located within easy reach of the driver. This element is chosen or modified so as to be isolated from the mass of the vehicle and connected to the detection means. These detection means are designed to be able to detect a drop in potential occurring in this screw (45) caused by the very low current flowing through the human body under a potential difference of 12V. To activate this mass detection element, it suffices for the driver or a passenger to touch with his finger both this fixing screw (45) and an element of the vehicle at ground potential, for example the surface

  metallic ignition key lock.

  These authorization detection means can be programmed to allow the storage of a permanent authorization as described above. This storage can for example be triggered by a continuous activation of the authorization detection means for a duration greater than a determined duration, for example greater than ten seconds. Clearing

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  of this permanent authorization can for example be done by a new

similar maneuver.

  According to a variant, the authorization detection means can be any known means of identification, such as a passive transponder, a coded circuit communicating by an electrical connector, a chip card reading terminal, or a data entry keyboard. a code. In the case of combining the device according to the invention with another starting prohibition system, the identification means can be common to the two devices. Disabling the immobilizer system without proper identification will then leave the device according to the invention active. It is also possible to provide an identification mode deactivating the immobilizer but not the device according to the invention, so as to be able to comply with the orders of a violent thief by starting the vehicle while letting the alert count and the flight situation procedure. It is also possible to provide a specific identification code activating the storage of a permanent authorization, or of an authorization valid permanently for a determined period, or of a plurality of authorizations in a determined number. The alert event detection means comprise an electrical connection between the processing means and a door contactor (41) or a pole of an alert element supplied when an event occurs that has to be recognized as an event. 'alert. This alert element may for example be a ceiling light (40) of lighting lit by

  opening any door or opening of the vehicle.

  This alert element can also be a volumetric detection device, for example a microwave detector, providing a positive potential when a determined region is crossed by a moving body. It is thus possible to apply the method according to the invention to a discoverable car or to a boat, even if the attack occurs without opening an opening. This alert element can also be a contactor

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  or a relay controlled by an external device, for example by a radio or telephone signal receiver used to trigger the alert countdown as described above. This alert element can also be a device for detecting the proximity of a radio transmitter or a passive electronic transponder worn by the legitimate driver. The removal of the legitimate driver, if necessary for a period longer than a determined period, will then trigger the provision of a positive potential by this element

  alert, thus communicating to the processing means an alert event.

  This alert element can also detect the possibility of a change of conductor by a thermal detection device of the human body, or a

  weight detection device integrated in the driver's seat.

  Alternatively, the operation of the device, or the start of the alert count, can be signaled to the driver by means of

  signaling, such as an indicator light (39).

  The actions carried out during the flight situation procedure include the control of one or more audible warning devices, such as the vehicle warning device or a siren, and of audible warning devices, such as direction or warning devices (32). vehicle signaling or lighting. These actions also include the control of a motor relay (35) interrupting an electrical communication necessary for the operation of the motor, as a signal between the computer (38) and the motor (37), or the electrical supply of the pump to fuel, or the power supply to an ignition coil. Such a relay can also be installed so as to send a positive potential to a device controlling degraded or different operation of the engine, or to a device memorizing a prohibition of operation of the starter or of a gearbox.

automatic speed.

  The equivalent of a permanent authorization can also be obtained by installing a key switch, making it possible to double the motor relay if it is connected to interrupt a connection in situation

23 2837764

  flight. Such a key switch can also be used to neutralize all or part of the effect of the actions executed by the processing means during a flight situation procedure. or to deliver to these same processing means a signal deactivating all or part of the device according to the invention. It will thus be possible for a legitimate driver to entrust the vehicle to a service provider without having to reveal the authorization actions to him, or to use his

  vehicle in the event of failure of this same device.

  It should be obvious to those skilled in the art that the present invention allows embodiments in many other specific forms without departing from the scope of the invention as claimed. Therefore, the present embodiments are for illustrative purposes, but may be

  modified in the field defined by the scope of the appended claims, and

  The invention should not be limited to the details given above.

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Claims (14)

  1. A method of protection against theft for a vehicle, implemented by means (31) for processing electrical or electronic information, characterized in that it comprises the following steps: - at a variable point in the process, detection (21, 27) of an authorization event, by means (43, 44, 45) of authorization detection, and storage, by the processing means in storage means, of a use authorization ; detection, by means (33) of detection of use, of a start (12) of use of the vehicle and memorization of a state of the vehicle as being in use, followed by a test (13) whether or not an authorization stored in the storage means is present; in the case of a start of use without memorized authorization, triggering (17) of a time count, called alert count; - in the case of a start of use with the presence of a memorized authorization, erasure (14) of this authorization and waiting (15) for an alert event; during the use of the vehicle, detection (24) of an alert event (16) and triggering (17) of a time count, called alert count; - at the end of the alert count, launch (18) of a flight situation procedure. 2337764   2. Method according to claim 1, characterized in that it further comprises the following steps: - detection of an authorization event (27) during a warning count (1 7); - cancellation (19) of this alert count; 3. Method according to claim 1 or 2, characterized in that it further comprises a step of memorizing a permanent authorization, this permanent authorization preventing the triggering of an alert count on the subsequent occurrence of a any number of events   alert, and until this permanent authorization is canceled.   4. Method according to one of claims 1 to 3, characterized in that   that the state of use of the vehicle is determined by the operation or the engine and possibly a start of movement of the vehicle, at least one alert event consisting of an opening of an access (24) to the vehicle, or the closing of such an access, or the detection of a departure of the driver out of the vehicle, or the detection of a distance for a duration greater than a determined duration of a transmitter or transponder object carried by the driver, or the triggering (29) voluntary signal from the vehicle or from a distance, or the crossing by an object or a person of a specific region surrounding the vehicle, or a combination of many of these events.   5. Method according to one of claims 1 to 4, characterized in that   that at least one authorization event is constituted by an action on an electrical or electronic contactor (43) by the driver or a passenger of the vehicle, or by the operation of a combination of several commands normally used for the operation or the use of the vehicle, or by establishing an electrical connection (450) passing through the human body between several elements (45, 46) constituting detection means and 26 2837764   communicating with the means of treatment, or by a combination of such actions.   6. Method according to one of claims 1 to 5, characterized in that   that the flight situation procedure (18) is executed immediately after the alert countdown (17), and includes the activation of engine starting prohibition means (35), or the permanent activation or repeated engine shutdown means or engine operation degrading means, or activation of light (32) or sound (42) signals, or activation of electronic information exchange with an external receiver device to the vehicle by radio transmission or   telephone, or a combination of such actions.   7. Method according to one of claims 1 to 6, characterized in that   that the alert countdown (17) is triggered or takes place without being notified to the driver.   8. Use of the method according to one of claims 1 to 6,   applied to theft protection. during legitimate use, of a motorized car or two-wheeled motorized vehicle, characterized in that it comprises the following stages: before starting the engine (22) or setting the vehicle in motion, or at during the alert count (17) triggered by this start-up, execution (21, 27) by a legitimate driver of the actions constituting an authorization event; normal use (28) of the vehicle by the legitimate driver; during engine operation, after taking control of the vehicle by an illegitimate driver, call (29) by the legitimate driver of a radio or telephone receiver device included in the vehicle, and transmission of a signal 27 2337764   triggering (17) an alert count or triggering (18) the flight situation procedure directly; use (31) of normal appearance of the vehicle during the alert count; - at the end of this alert count, triggering (18) of the flight situation procedure. 9. Theft protection device for a vehicle, comprising means (31) for processing electronic or computer information, characterized in that these processing means comprise means for storing information representing an authorization for use and a state of use of the vehicle, and communicate with means (33) for detecting the state of use of the vehicle, means (43, 44,) for detecting at least one authorization event, means for detecting at least one alert event, time counting means producing at least one timer of a given hardness, and means (32, 42, 35) for implementing a situation situation procedure flight. the processing means triggering a countdown of time, called an alert countdown, in the event of use of the vehicle in the absence of a memorized use authorization, then executing a flight situation procedure at The outcome of this countdown.   10. Device according to claim 9, characterized in that the means for detecting an authorization event comprise an electrical circuit detecting the communication of an element (44, 45) of the vehicle or of the device with the mass of the conveys, by electrical conduction through an electrical circuit (440) or through the body (450) of the conductor or a passenger in the vehicle.   11. Device according to one of claims 9 to 10, characterized in   what the means for detecting an alert event include a 28 2337764   electric circuit (41) reacting to the opening or closing of a vehicle access, or a device detecting access to the interior of the vehicle by crossing a determined region of the space surrounding the vehicle, or a device for detecting the presence near the vehicle of a passive transponder or a radio transmitter carried by the legitimate driver, or   a combination of these events.   12. Device according to one of claims 9 to 11, characterized in   that the means for detecting an alert event comprises a device receiving a radio signal, or a telephone call, or a signal   transmitted by a phone call.   13. Device according to one of claims 9 to 12, characterized in   that at the end of the alert count (17), the processing means execute a flight situation procedure by repeatedly actuating one or more audible (42) and light (32) alarms, or by interrupting the passage of at least one signal (380) or electric current necessary for the normal operation of the engine (37), or by communicating to the engine information commanding a complete or repeated stop or a drop in performance, or by activating means of prohibition restart   engine or vehicle after shutdown, or by a combination of these actions.   14. Device according to one of claims 9 to 13, characterized in   what it includes means for deactivating the device, these means possibly comprising either an electrical circuit (34) permanently ensuring certain functions (380) modified by the flight situation procedure. either means of memorizing a permanent authorization in the memorizing means, memorizing such a permanent authorization preventing the implementation or the initiation of the situation procedure