FR2780929A1 - Anti-theft system for motor vehicle, includes method of blocking windscreen transparency, either electrically or application of coating, to prevent driving of vehicle - Google Patents

Abstract

The system uses the opacity of windscreen glass as a visible deterrent to theft. This can be done by using a special glass for the windscreen for which the reversible passage of light may be controlled, or by changing the optical properties of the glass when subjected to radiation. The anti-theft system for a vehicle operates by rendering driving of the vehicle impossible, as a result of blocking the transparency of the windscreen. The transparency may be blocked by various means, such as the projection of an opaque film of material on to the windscreen which modifies its transparency. Alternatively the windscreen may be made of special glass for which the reversible passage of light may be controlled. A further option is the control of the windscreen transparency by projecting radiation on to the screen and thus affecting its optical properties. Other windows may also be affected, and the system may be electronically controlled.

Description

-1-

  ANTI-THEFT METHOD FOR A MOTOR VEHICLE

  AND DEVICES FOR IMPLEMENTING IT

DESCRIPTION

  The invention relates to an anti-theft method for a motor vehicle capable of making it impossible to drive the vehicle for lack of

  visibility. The invention also relates to devices for the implementation5 of said method.

  Effective protection against car theft must take into account the changing behavior of motorists, the public and especially thieves. Thus, alarm systems with sirens, giving the alert for a well-defined time and most often calling on goodwill

  third parties have lost their effectiveness due to the trivialization

  tion of alert and general indifference.

  With the implementation of coded key systems, current flights have

significantly reduced.

  However, technological advancements have spawned new thief practices of acquiring the most sophisticated keys

  by cunning, surprise, intimidation or aggression.

  In these cases the vehicles are in perfect working order, sometimes

even on the move.

  These thefts are most often characterized by extremely rapid intervention by thieves on the lookout for a moment of inattentiveness on the part of the motorist, or a favorable situation for appropriating the keys and the car under the threat of the driver being behind the wheel or

near his car.

  The essential object of the invention is to prevent these thefts by immobilizing the vehicle on the spot by making it temporarily "blind" by the

  removal of visibility essential for driving.

  The method according to the invention therefore consists in modifying the transparency

  windscreen so as to make it impossible to drive the vehicle

for lack of visibility.

  This process can be implemented in different ways: - either by projecting an opaque film on the exterior or interior surface of the windshield; -2- - either by using special panes whose transition from transparency to opacity and vice versa is made to order;

  - or by projecting a light ray on the windshield which interferes with its visibility.

  These are three non-limiting variants of a process which consists

  to make driving a vehicle impossible due to lack of visibility.

  The characteristics and advantages of the invention will appear more clearly on reading the following detailed description of the invention.

  at least one preferred embodiment of the invention given by way of nonlimiting example.

  The first solution is to spray an opaque film on the exterior or interior surface of the windshield. This can come from

  a pressure container, located for example under the hood of the vehicle, containing the liquid to be sprayed by means of a diffuser capable of transferring it onto the surface to be covered.

  The film can be bright in color and adhere strongly to ice, even in the rain. It can be of the hardening type to form, after a well-defined period, a more or less elastic film capable of being removed. I1 can be of the type requiring a solvent

specific for its removal.

  The second solution consists in using special panes whose transition from transparency to opacity and vice versa is made to order. The device for performing this function is included

in the glass.

  The third consists in projecting a light beam, in particular of the laser type, onto the windshield. It can be colored or create reflections that

affect visibility.

  These various solutions can be triggered: - either from inside the vehicle by means of a push button; - either from outside the vehicle by means of a programmable electronic system, fitted with a signal receiver;

  - either in combination with the other anti-theft devices of the vehicle.

  The purpose of thieves is obviously to take the vehicle

and leave with.

  -3- In the case of direct and immediate immobilization, triggered from inside the car, the thief's objective is materially defeated and any possible threat to the owner can do nothing more

  change, so it has become pointless.

  Indeed, the recirculation of the vehicle requires, depending on the products used, a more or less long time which is not generally

  acceptable for a thief anxious to get away quickly.

  Waiting for hardening of the projected liquid and its removal or erasure are obstacles to any attempt at theft. In the case of a flight with a successful departure or deliberately consented to move away from the thief, it is possible to use the retained remote control

  discreetly and independently of the keys.

  It is also possible to use the mobile phone to transmit a signal to the receiver located in the stolen vehicle to put

the system in service.

  In this case, the program only validates the system when the vehicle

  is stopped either at a stop sign or at a red light, ...

  The thief is trapped in the act, the car is immobilized and signaled to those around him, generally animated in cities, by the windshield covered with an opaque film of aggressive color and also

  possibly by a siren activated simultaneously.

  It can be combined when triggered with other systems

vehicle blocking.

  It can be used as a preventive measure in other situations, in the garage,

parked on the street, ...

  The car owner deactivates the system in this case

before hitting the road.

  Of course, the invention is not limited to the embodiments described for which other variants can be provided in the means used to modify the visibility of the windshield and possibly

  other windows of the vehicle, without thereby departing from the scope of the invention

tion.

Claims (8)

  1- Anti-theft method for a motor vehicle, characterized in that it consists in modifying the transparency of the windshield so as to make   driving the vehicle impossible due to lack of visibility.   2- Anti-theft method according to claim 1, characterized in that it consists in projecting onto the external or internal surface of windshield, an opaque film.   3- anti-theft method, according to claim 1, characterized in that it consists in using special panes whose passage of the   transparency to opacity and vice versa is made to order.   4- anti-theft method, according to claim 1, characterized in that it consists in projecting onto the windshield, a light ray, in particular of the laser type.   - Method according to any one of the preceding claims,   characterized in that it also consists in modifying, in addition, to   minus another window of the vehicle, including the rear window.   6- Anti-theft device for implementing the method according to claim 2, characterized in that it comprises a container under   pressure containing the liquid to be projected and a means allowing the projection   tion of it on the outer or inner surface of the windshield.   7- Anti-theft device for implementing the method according to one   any one of claims 2, 3 and 4, characterized in that it comprises   a means, of the push button type, allowing the triggering of the device   anti-theft device inside the vehicle.   8- Anti-theft device for implementing the method according to one   any one of claims 2, 3 and 4, characterized in that it comprises   a programmable electronic system, fitted with a signal receiver,   allowing the anti-theft device to be triggered remotely.   9- Anti-theft device for implementing the method according to one   any one of claims 2, 3 and 4, characterized in that it is   combined with other anti-theft devices in the vehicle.