Abstract:
Apparatus for securing a motor vehicle against theft uses a vehicle control device connected by a signaling link to a first control node of a vehicle module essential to mobilization of the vehicle, the essential module further having a power node connected to a power supply source. The apparatus comprises: an enable/disable control for conditionally disabling signaling along the signaling link, a user interface code input device communicating with the enable/disable control via a secure command link, and an armored encapsulation encapsulating the disable control and the control node and physically configured to render inoperable any of the disable control, the signaling link and the control node upon being tampered with.

Description:
FIELD AND BACKGROUND OF THE INVENTION  
       [0001]     The present invention relates to prevention of vehicle theft and, more particularly, to the prevention of vehicle theft using a combination of electronic or mechanical control and physical armored encapsulation.  
         [0002]     Vehicle theft is a well-known and widespread crime, causing severe financial damage and affecting the public sense of well-being and morale.  
         [0003]     Numerous motor vehicle anti-theft devices are known in the art. These include, inter alia, mechanical locks, electronic alarm systems, electronic engine immobilizers, automatic vehicle location systems and devices for disabling the fuel supply to the engine.  
         [0004]     Conventional alarm type theft preventing devices typically comprise a control unit, a loud speaker, a plurality of sensors and a remote controller. The control unit and the loud speaker are installed in the inside of the car, while the remote controller is used for transmitting a control signal to turn the control unit on or off. When the control unit is turned on, it is capable of triggering the loud speaker to give off an alarm signal to frighten the burglar and alert passers-by. Nowadays, it is appreciated that alarm signals themselves are ignored by passers by and thus do not in themselves deter the thief. Thus vehicles are typically further equipped with some kind of engine immobilizer. In one kind of immobilizer the power source of the starter is shut off whilst the legal owner has left the vehicle Such an immobilizer is only partly successful as often the thief is able to start the vehicle before the immobilizer has armed or he is able to disable the alarm by electrically bypassing it Alternatively, the thief can disable or reduce the operation of the alarm loud speaker by inserting a foamy material thereto. Other known systems choke off the fuel supply to the engine.  
         [0005]     A common drawback for many of the anti-theft systems is the ability of the thief to access the anti-theft system thereby to disable it. Some systems offer an armored enclosure to serve as defense against violent attacks of the switching device, and against attempts to tamper with the security system.  
         [0006]     U.S. Pat. No. 4,288,778 to Zucker teaches a method of using digital electronic anti-theft system integrally formed with a vehicle component.  
         [0007]     U.S. Pat. No. 4,209,709 to Betton discloses an electronic ignition system in which electronic circuitry is located in an auxiliary metallic housing which is configured to surround both the solenoid and starter motor of the vehicle. The electrical interconnection between the circuitry and the solenoid are accomplished within the protection of the auxiliary housing. U.S. Pat. No. 4,533,016 to Betton discloses an electronic circuit enclosed within a solenoid housing with means for inhibiting actuation of the solenoid in the absence of entry of a predetermined code from the ignition switch of the vehicle.  
         [0008]     French patent FR2764570 to Duval discloses a keypad controlling a starter relay voltage supply, where the starter motor may further be locked. Anti-theft screws with security lugs are used to avoid dismantling of the starter.  
         [0009]     U.S. Pat. No. 5,564,376 to Labelle, discloses a housing, which is connectable to the starter motor casing, and serves as enclosure to a control circuit. U.S. Pat. No. 6,227,158 to Labelle discloses a similar arrangement for the starter solenoid; U.S. Pat. No. 6,116,201 and WO0071395 to Labelle teach the use of the starter solenoid housing itself as enclosure for an integrated security chip.  
         [0010]     Also of prior art of interest are devices which are used to control the security system. These include, U.S. Pat. No. 4,733,638 which discloses a hand-held transmitter, French Patent No. FR2769562 which discloses the use of an RF signal, U.S. Pat. No. 6,069,411 which discloses the use the Electronic Serial Number of a cellular phone as an ID code, U.S. Pat. No. 5,808,543 which discloses such a system dependent on a radio frequency identification device badge usually used in vehicle key systems, and U.S. Pat. No. 5,704,008 which teaches a voice or password recognition control of the starter solenoid.  
         [0011]     Despite the use of the above devices, thieves nevertheless find ways and means of overcoming (e.g., by bypassing) the various protection devices. Mechanical locking devices are broken and by-passed, cut-off valves are circumvented or disabled, electronic engine immobilizers are hot-wired and even sophisticated anti-theft systems are overcome by key-theft or lock picking. A recently observed theft method involves a replacement kit for the vehicle Engine Control Unit (ECU), which is used to bypass the whole security system. A thief equipped with a pre-prepared replacement kit, a key and a key decoder, can fit the unit within minutes and drive away with the vehicle.  
         [0012]     It is thus appreciated that the non-accessibility of the anti-theft system to the thief is of utmost importance. Furthermore, it is important that such non-accessible system would be protected against bypassing. Many known physically armored devices are aimed at protecting the vehicle via starter disabling methods. Such devices may be categorized into two groups, built-in control devices, destined to be integrated within the solenoid housing, and add-on armored control devices, destined to be mounted over the solenoid housing. Built-in control devices require re-design of the starter solenoid for new vehicles, or the exchange of a solenoid or solenoid-starter assembly in pre-existing vehicles.  
         [0013]     Add-on armored control devices according to prior art require very large protective covers that may interfere with engine compartment serviceability and with proper ventilation of the engine bay. In addition, installation of presently known add-on armored control devices is very complicated, if at all possible, in existing vehicles. Furthermore, prior art built-in or add-on control devices may be unable to withstand the harsh environmental conditions typical of vehicle engine compartments.  
         [0014]     Examples of such protective covers are given in U.S. Pat. Nos. 6,351,209 and 5,548,164. These examples suffer from some or all of the disadvantages listed above they further are very complex to manufacture, require considerable installation efforts and require a plurality of models to fit most vehicle types.  
         [0015]     There is thus a widely recognized need for, and it would be highly advantageous to have, a system for preventing vehicle theft devoid of the above limitations.  
       SUMMARY OF THE INVENTION  
       [0016]     According to a first aspect of the present invention there is provided apparatus for securing a motor vehicle against theft, the motor vehicle having a starting switch connected by a signal wire to a control node of a starter unit, the starter unit having a power node connected to a starter motor, and a power node connected to a power supply source, the apparatus comprising:  
         [0017]     an enable/disable control for conditionally disabling signaling along said signal wire, and  
         [0018]     an armored encapsulation encapsulating said disable control and said first control node and physically configured to render inoperable at least one of said enable/disable control, said signal wire and said control node upon being tampered with.  
         [0019]     In the following the component selected from the enable/disable control, the signal wire and the control node, which is rendered inoperable, is referred to also as the essential component.  
         [0020]     A control apparatus comprises a switching device such as an electro mechanical relay or a solid-state device such as a field effect transistor (FET) or similar signal or power switching devices, and a logic device such as an electronic circuit governing the switching device. The control apparatus toggles a connection between an energy source or a signal source and a module essential to mobilizing the vehicle so as to toggle the state of the signal wire from a transmissive state to a non-transmissive state or vice-versa.  
         [0021]     Preferably, the size of the at least one armored encapsulation is selected to substantially encapsulate the control apparatus and the signal wire connecting the control apparatus to the essential module.  
         [0022]     The type of signal communication with the control apparatus may be selected from the group consisting of a wireless electrical communication, a wired electrical communication, and an optical link.  
         [0023]     A module essential to mobilize the vehicle, and whose disablement is used to provide the security protection may be any of a starter, a solenoid of a starter, an integrated starter-alternator device, a Dynamo-Starter device, a starter-generator, a power-supply unit, a hand brake, a gearshift selector and an electric part of a hybrid-powered vehicle. In the following, such a module is referred to also as the essential module.  
         [0024]     The locking device itself is preferably designed and constructed to perform electrical switching so as that the positioning of the locking device comprises selecting between connecting or disconnecting or bypassing the electrical switch through the locking device.  
         [0025]     The control apparatus may be designed, constructed or positioned so as to selectively activate an electro-mechanical actuator control device that mechanically limits the motion of the solenoid internal plunger, thereby to indirectly prevent a starter motor of the vehicle from rotating an engine of the vehicle.  
         [0026]     The control apparatus may be designed, constructed or positioned so as to selectively activate an electromechanical actuator control device to mechanically limit the motion of the starter internal mechanical coupler, thereby preventing a starter motor of the vehicle from engaging and thus rotating an engine shaft of the vehicle.  
         [0027]     The control apparatus may be designed, constructed or positioned so as to selectively activate an electromechanical actuator control device to mechanically limit the motion of the starter solenoid actuation lever. The lever is normally used to actuate the engagement of the shaft of the starter motor to the vehicle engine shaft flywheel, thus the limiting of the motion of the solenoid lever prevents a starter motor of the vehicle from engaging and thus rotating an engine shaft of the vehicle.  
         [0028]     According to still a further aspect of the present invention the system comprises a volume generating mechanism being geometrically compatible with at least one pre-existing component of the at least one essential module and at least one part of the armored encapsulation. The said mechanism generates a volume surrounding at least a part of the essential module, said volume shape and size being defined in the at least one armored encapsulation and being sufficient for encapsulating the control apparatus while forming a substantially compact assembly.  
         [0029]     According to still further features in the described preferred embodiments the volume generating mechanism comprises at least one elongator positioned between the essential module and the at least one armored encapsulation so as to increase a volume for being sufficient for encapsulating the control apparatus.  
         [0030]     According to further features in the described preferred embodiments the volume generating mechanism comprises at least one elongator forming an extension to one power stud of an electric essential module such as the starter solenoid.  
         [0031]     According to still further features in the described preferred embodiments the at least one electric power stud elongator is made of a combination of a conductive material and an insulating material, designed and constructed for preventing electric contact between the at least one armored encapsulation and at least one other part of the system selected from the control apparatus or at least one electric power stud.  
         [0032]     Typically, the control apparatus comprises an enable/disable control, which may be a mechanical switch such as an electro mechanical relay or a solid-state device such as a field effect transistor (FET) or similar signal or power switching devices, and a logic device such as an electronic circuit governing the switching device. The control apparatus toggles a connection between an energy source or a signal source and the said essential module so as to toggle the state of the signal wire from a transmissive state to a non-transmissive state or vice-versa. Alternatively the control device uses other methods of enabling or disabling signaling along the signal wire, either directly or indirectly.  
         [0033]     According to still further features in the described preferred embodiments a body of the at least one armored encapsulation is selected from the group consisting of a shell body and a solid body.  
         [0034]     According to further features in the described preferred embodiments the size of the at least one armored encapsulation is selected to substantially encapsulate the control apparatus and the signal wire connecting the control apparatus to the essential module.  
         [0035]     According to still further features in the described preferred embodiments the at least one armored encapsulation is mounted to the essential module by being connected to at least one pre-existing integral component of it.  
         [0036]     According to still further features in the described preferred embodiments the at least one pre-existing integral component of the at least one essential module is a mounting nut or an assembly nut.  
         [0037]     According to still further features in the described preferred embodiments the at least one armored encapsulation comprises a first part, and a second part being geometrically compatible with the first part, the first and the second parts may be rotated to a plurality of angles, such as that the encapsulating comprises rotating the first part relative to the second part so as to match orientation of the at least one essential module.  
         [0038]     According to still further features in the described preferred embodiments the at least one armored encapsulation comprises a plurality of positioning pairs, such as a pin-groove pair, each corresponding to one angle of the plurality of angles.  
         [0039]     According to still further features in the described preferred embodiments the system further comprises a user interface device being designed and constructed for activating and deactivating the control apparatus via signal communication with the control apparatus, selected from the group consisting of a wireless electrical communication, a wired electrical communication, and an optical link.  
         [0040]     According to still further features in the described preferred embodiments the user interface device comprises recognition circuitry for recognizing a user prior to the activating and deactivating.  
         [0041]     According to still further features in the described preferred embodiments the recognition circuitry is selected from the group consisting of keyed-in password recognition circuitry, spoken password recognition circuitry, biometric voice recognition circuitry, biometric fingerprint recognition circuitry, biometric bone structure recognition circuitry and biometric iris-patterns recognition circuitry.  
         [0042]     According to another aspect of the present invention there is provided a method of installing a theft-preventing system within a vehicle, the method comprising: providing a control apparatus and positioning it so as to control operation of at least one module being essential to mobilization of the vehicle, and encapsulating the control apparatus and at least a portion of the at least one essential module using at least one armored encapsulation so as to prevent accessing the control apparatus without substantially damaging the at least one armored encapsulation and the at least one essential module, thereby preventing unauthorized mobilization of the vehicle.  
         [0043]     According to further features in the described preferred embodiments the encapsulating is done so as to encapsulate essentially the control apparatus and the signal wire connecting the control apparatus to the essential module.  
         [0044]     According to still further features in the described preferred embodiments the encapsulating comprises independently integrating the control apparatus and the at least a portion of the at least one essential module in the solid body of the at least one armored encapsulation.  
         [0045]     According to still further features in the described preferred embodiments the method further comprises providing a user interface device electrically communicating with the control apparatus, and operating the user interface device so as to activate or deactivate the control apparatus.  
         [0046]     According to still further features in the described preferred embodiments the method further comprises fastening the at least one armored encapsulation to a body of the vehicle using at least one anti-vandal security nut, the at least one security nut being designed and constructed for preventing a removal of the at least one armored encapsulation.  
         [0047]     According to still further features in the described preferred embodiments the method further comprises allowing bypassing the control module by performing a predetermined procedure.  
         [0048]     According to still further features in the described preferred embodiments the method further comprises positioning a heat isolating interface between the at least one armored encapsulation and an engine or an engine bay of the vehicle, for preventing heat transfer from the engine to the at least one armored encapsulation.  
         [0049]     According to still further features in the described preferred embodiments the at least one essential module is selected from the group consisting of a starter, a solenoid of a starter, an integrated starter-alternator device, a Dynamo-Starter device, a starter-generator, a power-supply unit, a hand brake, a gearshift selector and an electric part of a hybrid-powered vehicle.  
         [0050]     According to preferred embodiments of the present invention the at least one essential module is the solenoid governing the starter motor of the engine of the vehicle, and the control apparatus is designed and constructed and positioned so as to control power or data signals transmitted through a signal conducting wire connecting an ignition switch of the vehicle and a control node of the solenoid of the starter.  
         [0051]     According to further features in the described preferred embodiments the armored encapsulation that protects the control apparatus and the solenoid control node is being attached to any other pre-existing integral part of the solenoid such as to a power node stud of the solenoid or to a mounting nut or to an assembly nut so that in the event of an attempt to interfere with the encapsulation, a solenoid node is rendered useless.  
         [0052]     According to still further features in the described preferred embodiments the system further comprises a self-destructing assembly positioned within the at least one armored encapsulation, the self-destructing assembly being designed and constructed so that if the at least one armored encapsulation is at least partially damaged, the self-destructing assembly disintegrates, hence providing the damaging of the at least one essential module.  
         [0053]     According to still further features in the described preferred embodiments the armored encapsulation being at least partially damaged is selected from the group consisting of the armored encapsulation being at least partially bended, being at least partially twisted, being at least partially strained, being at least partially pried open and being at least partially broken.  
         [0054]     According to still further features in the described preferred embodiments the self-destructing assembly comprises a conducting foil.  
         [0055]     According to still further features in the described preferred embodiments at least one anti-vandal security nut comprises a first part, a second part and a third part, the second part being positioned between the first and the third part and comprises a detachable material so that if a shear force applied onto the first part exceeds a predetermined maximal value, the first part detaches from the third part.  
         [0056]     According to still further features in the described preferred embodiments a shape of the third part is characterized by smooth edges designed so as to prevent opening of the third part, thereby to prevent removal of the at least one armored encapsulation.  
         [0057]     According to still further features in the described preferred embodiments the connecting the at least one security nut is by applying a torque that induces a shear force being larger than the predetermined maximal value, so as to detach the first part from the third part.  
         [0058]     According to still further features in the described preferred embodiments the first and the second parts have a sufficiently large combined longitudinal dimension so as to encapsulate the at least one elongator.  
         [0059]     According to still further features in the described preferred embodiments the system comprises at least one secured bypassing device enabling to circumvent the control apparatus by a predetermined procedure.  
         [0060]     According to still further features in the described preferred embodiments the secured bypass device is at least one locking device allowing a removal of at least a portion of the at least one armored encapsulation by a predetermined procedure, without causing damage to the at least one armored encapsulation.  
         [0061]     According to still further features in the described preferred embodiments the bypassing device comprises an electrical switch connected to the at least one essential module so that if the predetermined procedure is executed, the control apparatus is bypassed.  
         [0062]     According to still further features in the described preferred embodiments the locking device itself is designed and constructed to perform electrical switching so as that the positioning of the at least one locking device comprises bypassing the electrical switch through the locking device.  
         [0063]     According to still another aspect of the present invention there is provided a solenoid system for controlling supply of electrical current to a starter of a vehicle, the solenoid system being encapsulated by an armored encapsulation and having a solenoid and a system for preventing theft of the vehicle, the system comprising a control apparatus for selectively controlling the motion of an internal plunger, the method comprising selectively preventing motion of an internal plunger of the solenoid, thereby preventing initial ignition of the vehicle, wherein the controlling the motion is selected from the group consisting of mechanically controlling and electrically controlling.  
         [0064]     According to further features in the described preferred embodiments, the control apparatus comprises an electrical switch operable to selectively control electrical power supply or data signals transmitted to the solenoid internal plunger through a wire winding the internal plunger in such a manner that the motion of the internal plunger is allowed, or disabled.  
         [0065]     According to still further features in the described preferred embodiments the control apparatus is operable to selectively limit a motion of a mechanical shift lever solenoid output being operatively associated with the mechanical engagement of the starter motor of the vehicle, thereby to indirectly prevent the starter motor from rotating an engine of the vehicle.  
         [0066]     According to still further features in the described preferred embodiments the control apparatus is designed, constructed and positioned so as to selectively activate an electromechanical actuator control device selectively operable to mechanically limit the motion of the solenoid internal plunger, thereby to indirectly prevent a starter motor of the vehicle from rotating an engine of the vehicle,  
         [0067]     According to still further features in the described preferred embodiments the bypassing the control apparatus is by disabling the mechanical actuator so as to allow the motion of the internal plunger.  
         [0068]     According to still further features in the described preferred embodiments the control apparatus controls a blocking mechanism positioned opposite an elongation rod which is connected to the solenoid internal plunger, the mechanism being designed and constructed so as to selectively limit the motion of the internal plunger.  
         [0069]     According to still further features in the described preferred embodiments the bypassing the control apparatus is by disabling the blocking mechanism so as to allow the motion of the internal plunger with the elongation rod.  
         [0070]     According to still further features in the described preferred embodiments the selectively preventing the internal plunger motion comprises irreparably disabling the motion, if an attempt is made to open an armored encapsulation of the solenoid.  
         [0071]     According to still a further aspect of the present invention there is provided a power-supply device for supplying power to a vehicle and preventing theft thereof, the power-supply unit comprising a plurality of electrolytic cells and a short circuit controlled by a control apparatus switching device, the short circuit being connected so as to bypass at least one of the plurality of electrolytic cells, thereby to control a value of voltage supplied by the power-supply unit.  
         [0072]     According to further features in preferred embodiments of the invention described below, the power-supply device further comprises a self-destructing assembly being designed and constructed so that if the power-supply device is at least partially damaged, the self-destructing assembly disintegrates, hence disabling at least one of the plurality of electrolytic cells.  
         [0073]     According to still further features in the described preferred embodiments the self-destructing assembly comprises a conducting foil and at least one compatible connector connected to the conducting foil.  
         [0074]     According to still further features in the described preferred embodiments the at least one armored encapsulation is designed and constructed so as to encapsulate the positive terminal of the power-supply unit, the power input terminal of a starter solenoid of the vehicle and the wire connecting them.  
         [0075]     According to still further features in the described preferred embodiments the at least one armored encapsulation is designed and constructed so as to prevent heating of the control apparatus by applying at least one of the following means in the construction of the armored encapsulation: using a construction material characterized by low heat capacity, using at least one reflective layer capable of reflecting heat radiation there from, integrating at least two layers separated by a medium capable of preventing heat convection, being sufficiently small so as to allow ventilation within the engine bay.  
         [0076]     According to still further features in the de scribed preferred embodiments the control apparatus is designed and adapted to be locatable within an engine bay of the vehicle by applying at least one of the following means in the construction: using at least one electronic circuit assembly being formed in a dielectric material selected to withstand any one of high temperature, moisture, electrical sparks, mechanical vibrations and chemical vapors, being sufficiently small so as to allow ventilation within the engine bay, using components that are heat resistant.  
         [0077]     According to further features in preferred embodiments of the invention described below, the system further comprises a communication device, being able to communicate with a remote control center, The communications device may optionally be able to receive responses from the remote control center thereby to apply activation or deactivation commands to the control apparatus.  
         [0078]     According to still further features in the described preferred embodiments the method further comprises positioning the communication device within the at least one armored encapsulation, wherein the communication device being operable to transmit alert signals to the remote control center if the at least one armored encapsulation is at least partially damaged.  
         [0079]     Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, suitable methods and materials are described below. In case of conflict, the patent specification, including definitions, will control. In addition, the materials, methods, and examples are illustrative only and not intended to be limiting. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0080]     The invention is herein described, by way of example only, with reference to the accompanying drawings. With specific reference now to the drawings in detail, it is stressed that the particulars shown are by way of example and for purposes of illustrative discussion of the preferred embodiments of the present invention only, and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the invention. In this regard, no attempt is made to show structural details of the invention in more detail than is necessary for a fundamental understanding of the invention, the description taken with the drawings making apparent to those skilled in the art how the several forms of the invention may be embodied in practice.  
         [0081]     In the drawings:  
         [0082]      FIG. 1  is a schematic illustration of a system for preventing theft of a vehicle, according to a preferred embodiment of the present invention.  
         [0083]      FIGS. 2   a - b  are schematic illustrations of an initial ignition circuit without (a) and with (b) the system for preventing theft of a vehicle, according to a preferred embodiment of the present invention.  
         [0084]      FIG. 3   a  is a schematic illustration of a starter, a solenoid and armored encapsulation, according to a preferred embodiment of the present invention.  
         [0085]      FIG. 3   b  is a schematic illustration of an armored encapsulation unit having two parts, according to a preferred embodiment of the present invention.  
         [0086]      FIG. 4   a  shows relative locations and connection between the various parts of the system and the solenoid, according to a preferred embodiment of the present invention;  
         [0087]      FIG. 4   b  is a schematic illustration of elongators which are used according to a preferred embodiment of the present invention.  
         [0088]      FIGS. 4   c - d  are schematic illustrations of security nuts, according to a preferred embodiment of the present invention.  
         [0089]      FIG. 5  shows relative locations and connection between the various parts of the system and the solenoid, together with a locking device, which may be used according to a preferred embodiment of the present invention.  
         [0090]      FIG. 6  is a schematic illustration of a complete starter assembly.  
         [0091]      FIG. 7  is a schematic illustration of the interior portion of a solenoid in which an internal plunger is controlled electrically, according to a preferred embodiment of the present invention.  
         [0092]      FIG. 8  is a schematic illustration of the interior portion of a solenoid in which an internal plunger is controlled mechanically, according to a preferred embodiment of the present invention.  
         [0093]      FIGS. 9   a - c  are schematic illustrations of the system in which a power-supply unit of the vehicle is electrically controlled, according to a preferred embodiment of the present invention.  
         [0094]      FIG. 10  is a schematic illustration of the power-supply unit and various protections thereof, according to a preferred embodiment of the present invention.  
         [0095]      FIG. 11  is a flowchart of a method of installing a theft-preventing system, according to a preferred embodiment of the present invention.  
         [0096]      FIG. 12  is a flowchart of a method of preventing theft of a vehicle, according to a preferred embodiment of the present invention. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0097]     The present embodiments are of a system for preventing theft of a vehicle, which can be installed in various locations within the vehicle. Specifically, the present embodiments are of a system which combines electronic or mechanical control with a physical armored encapsulation. The present embodiments are further of a method of installing the system and a method of preventing theft of the vehicle. The present embodiments are still further of a starter system, a solenoid system and a power-supply device, incorporating the principles of the system.  
         [0098]     The principles and operation of a system for preventing theft of a vehicle according to the present embodiments may be better understood with reference to the drawings and accompanying descriptions.  
         [0099]     Before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments or of being practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein is for the purpose of description and should not be regarded as limiting.  
         [0100]     According to one aspect of the present invention there is provided a system for preventing theft of a vehicle, the vehicle having at least one essential module. The essential module can be any module which is essential to mobilization of the vehicle, e.g., a starter, a power-supply unit, a hand brake, an integrated starter-alternator device, a Dynamo-Starter device (also known as dynostart), a gearshift selector, an electric part of a hybrid-powered vehicle, and the like.  
         [0101]     Referring now to the drawings,  FIG. 1  is a schematic illustration of a system according to a first preferred embodiment of the present invention. System  20  comprises a control apparatus  22  for controlling operation of essential module  24 , and both the control apparatus and the essential module are housed within an armored encapsulation  26 . One or more of the shape, configuration, material, size and/or location of armored encapsulation  26  within the vehicle is designed so as to prevent accessing control apparatus  22  without substantially damaging armored encapsulation  26 . The armored encapsulation is designed so that if it is damaged, so is the essential module  24 , thereby preventing the mobilization of the vehicle. A number of possibilities for achieving such a result are described in greater detail hereinbelow. According to a preferred embodiment of the present invention armored encapsulation  26  is designed to be located within an engine bay of the vehicle. Furthermore, armored encapsulation  26  is preferably designed to be sufficiently small so as to allow ventilation within the engine bay.  
         [0102]     According to preferred embodiments of the present invention armored encapsulation  26  may have a shell body, a solid body or a combination thereof. Thus, in one embodiment control apparatus  22  and the portion of essential module  24  are surrounded by the shell body of armored encapsulation  26  and in another embodiment the portion of essential module  24  and/or control apparatus  22  are integrated in the solid body armored encapsulation  26 .  
         [0103]     Armored encapsulation  26  is preferably designed and constructed so as to prevent malfunctioning of control apparatus  22  by heating. Such malfunctioning prevention may be achieved in more than one way. For example, in one embodiment, armored encapsulation  26  comprises a material characterized by low heat capacity; in another embodiment armored encapsulation  26  comprises at least one reflective layer being for reflecting heat radiation therefrom; in an additional embodiment armored encapsulation  26  comprises at least two layers which are separated by a medium capable of preventing heat convection; in still an additional embodiment, armored encapsulation  26  is connected to the engine bay via a heat isolating interface, for preventing heat transfer from engine to armored encapsulation  26 .  
         [0104]     The heating of control apparatus  22  may also be prevented by selecting an appropriate material from which to form control apparatus  22 . For example, if control apparatus  22  comprises one or more electronic circuit assemblies, these assemblies are preferably formed or implanted in a dielectric material which is selected to withstand high temperature. Additionally and preferably the dielectric material also withstands moisture, electrical sparks, mechanical vibrations and/or chemical vapors.  
         [0105]     According to a preferred embodiment of the present invention, control apparatus  22  may be activated automatically when the vehicle is in a static state or, alternatively, control apparatus  22  may be activated by the user via a user interface device  28 , electrically communicating with control apparatus  22 , e.g., via a communication device  29 . User interface device  28  also serves for deactivating control apparatus  22 , before the vehicle departs. To prevent the use of user interface device  28  by an unauthorized person, user interface device  28  preferably comprises recognition circuitry, such as, but not limited to, keyed-in password recognition circuitry, spoken password recognition circuitry, biometric voice recognition circuitry, biometric fingerprint recognition circuitry, biometric bone structure recognition circuitry and/or biometric iris-patterns recognition circuitry.  
         [0106]     Communication device  29  may also serve for communicating with a remote control center, thereby combining system  20  with an Automatic Vehicle Location (AVL) system. It should be understood that in certain systems, more than one communication device may be used, for example, a single system may use a short-range communication device for establishing communication between the user and control apparatus, and a long-range communication device for establishing communication between system  20  and the remote control center. Any of the communication devices may be wireless (e.g., employing a radiofrequency (RF) transmitter-receiver) or wired.  
         [0107]     As used herein, the phrase communication device  29  interchangeably refers to any and all suitable communication devices.  
         [0108]     Thus, if armored encapsulation  26  is partially damaged, communication device  29  transmits signals to an AVL operator, who may manually transmit responses back to communication device  29  for activating control apparatus  22 , thereby to immobilize the vehicle.  
         [0109]     According to a preferred embodiment of the present invention, system  20  may further comprise a self-destructing assembly  23  designed and positioned so that any attempt to open or punch armored encapsulation  26  results in a total electrical discontinuity. More specifically, if and when armored encapsulation  26  is at least partially damaged, self-destructing assembly  23  disintegrates and disables essential module  24 .  
         [0110]     One example of a self-destructing assembly  23  is a thin wide conductor, such as, but not limited to, flex wire circuits coupled with thin and protected wide connectors. The flex wire circuits disintegrate upon a violent attempt to open or punch armored encapsulation  26 , and the protected wide connectors prevent the thief from creating an alternative contact (“hot-wiring”). Preferably, the self-destructing assembly is positioned in a non-accessible location, e.g., buried within armored encapsulation  26 .  
         [0111]     Before providing a further detailed description of system  20  for preventing theft of a vehicle, as delineated hereinabove and in accordance with the present embodiments, attention will be given to the advantages offered thereby.  
         [0112]     The system operates at two protection levels. A first protection level is provided by control apparatus  22  which disables the functionality of essential module  24  when the vehicle is in a static state, and a second protection level is provided by armored encapsulation  26  when an attempt to bypass the first protection occurs. In this case, the design and installation of armored encapsulation  26  preferably causes essential module  24  to be damaged beyond immediate repair. Thus, since it is impossible to mobilize the vehicle without complete functioning of essential module  24 , the theft is prevented.  
         [0113]     Another advantage of the present embodiments over prior-art systems is that the present embodiments do not present a risk that might accidentally hamper the vehicle safety while in motion. It is recognized that many prior art systems, such as systems that are based on selective control of engine ignition circuits, fuel supply lines and the like, may become operative while the vehicle is mobile, for example due to malfunction or due to accidental activation. Such failure may lead to loss of ignition, engine stall and eventually loss of control by the driver due to the absence of power steering and power assisted braking.  
         [0114]     A more detailed description of the preferred embodiments of the present invention is now provided.  
         [0115]     Hence, in one embodiment, essential module  24  is the starter of the vehicle. In this embodiment control apparatus  22  is designed and constructed so as to control the operation of the starter. This may be done, for example, by controlling electrical signals transmitted through a signal wire which connects the ignition switch with the starter solenoid of the vehicle.  
         [0116]     Reference is now made to  FIGS. 2   a - b  which are schematic illustrations of an initial ignition circuit without ( FIG. 2   a ) and with ( FIG. 2   b ) the system for preventing theft of the vehicle, as delineated hereinabove. The initial ignition circuit commonly includes a solenoid  1 , a starter motor  2  and an ignition switch  3 . Solenoid  1  is typically connected to a power-supply unit  4  via a “B” terminal  202 ; to starter motor  2  via an “M” terminal  203  and to ignition switch  3  via an “S” terminal  201 . The “S” terminal is connected to a signal wire having a first end  211  and a second end  212 . Terminals  201 ,  202  and  203  typically carry a voltage of 12, 24 and/or 42 volts DC, but other voltage values are not excluded. “S” terminal  201  typically carries a low power signal, while the power carried by terminals  202  and  203  is typically higher. Solenoid  1 , starter motor  2  and power-supply unit  4  are typically grounded to a large conductive material, e.g., to the vehicle body.  
         [0117]     Reference is now made to  FIG. 3   a , which is a schematic illustration of starter motor  2 , solenoid  1  and armored encapsulation  26 . When ignition switch  3  is switched on and pressed further to a spring-loaded position, solenoid  1  supplies high current to motor  2 . Once supplied with sufficiently high current, a shaft  21  of motor  2  engages a compatible shaft in the vehicle&#39;s engine (not shown). At the same time, shaft  21  rotates the compatible shaft thereby enabling initial ignition or cranking of the engine.  
         [0118]     According to a preferred embodiment of the present invention, control apparatus  22  comprises a relay  210  and an electronic circuit  105  controlling relay  210 , so as to toggle signal wire  211 / 212  between a transmissive state and a non-transmissive state. As stated, control apparatus  22  preferably communicates with a user interface device  28 . In this embodiment, user interface device  28  communicates with circuit  105 , e.g., via wire  213  or via communication device  29  (not shown in  FIGS. 2   a - b ), and hence serves for operating relay  210 , depending on the choice of the authorized user. As stated, communication device  29  may also be wireless, thus, the electrical communication between user interface device  28  and circuit  105  is preferably by RF radiation.  
         [0119]     Thus, when signal wire  211 / 212  is toggled by relay  210  to a non-transmissive state, signals cannot be transmitted from first end  211  to second end  212 , and motor  2  does not engage the engine. According to a preferred embodiment of the present invention the size of armored encapsulation  26  is selected to encapsulate essentially “S” terminal  201 , control apparatus  22  (including relay  210  and circuit  105 ) and first end  211 . The protection of terminals  202  and  203  is not required because supplying power to these terminals only causes motor  2  to rotate without being engaged to the engine, thus cranking does not occur.  
         [0120]     A particular advantage of the presently preferred configuration of this embodiment is that, unlike prior art systems, only a portion of the starter components are encapsulated, whereas other, relatively large, components are not encapsulated. One ordinarily skilled in the art would appreciate that such configuration minimizes the size of the system and hence facilitates easy installation, and, in addition, minimizes undesired intervention of the system with other vehicle systems. The present embodiment therefore keeps the maintainability of both pre-existing new vehicles.  
         [0121]     Armored encapsulation  26  is preferably manufactured cylindrically (see  FIG. 3   a ) so as to allow the encapsulation of “S” terminal  201 , circuit  105 , relay  210  and first end  211 . Preferably, armored encapsulation  26  is manufactured with one or more openings  102 , to facilitate mounting of armored encapsulation  26  on terminals  202  and/or  203 , as further detailed hereinunder with reference to  FIG. 4   a.    
         [0122]     The present embodiments successfully provide a solution to the problems associated with installation of system  20  in pre-existing vehicles. It is appreciated that the solenoids of different vehicle may differ in the positions of terminals  202  and  203  thereon.  
         [0123]     Reference is now made to  FIG. 3   b , which is a schematic illustration of an alternative design of armored encapsulation  26 , according to a preferred embodiment of the present invention. In this embodiment, armored encapsulation  26  comprises a first part  1011  and a second part  1012 , second part  1012  serves as a base for first part  1011 , so that a relative orientation between first  1011  and second  1012  part may vary, depending on the type of solenoid  1 .  
         [0124]     A preferred shape of armored encapsulation  26  is, as stated, a cylinder, so as to match the shape of solenoid  1 . It happens to be that the physical separation between terminals  202  and  203 , and the diameters of solenoid  1 , terminal  202  and terminal  203  are typically uniform for most existing vehicles of the same manufacturer, and often even between different manufacturers. On the other hand, the orientation of terminals  202  and  203  relatively to starter motor  2  is different from one vehicle type to the other.  
         [0125]     Thus, for a cylindrical armored encapsulation  26 , second part  1012  preferably shaped as a disk, having openings  102  through which terminals  202  and  203  can protrude. The installer can rotate second part  1012  relatively to first part  1013  until the relative orientation between first  1013  and second  1012  parts matches the relative orientation between terminals  202  and  203  and starter motor  2 . Several sizes of armored encapsulation  26  may be manufactured, so that armored encapsulation  26  is also compatible with non-standard diameters of solenoid  1  and/or terminals  202  and  203 .  
         [0126]     A skilled artisan would appreciate that the presently preferred embodiment of the invention, in which armored encapsulation  26  is composed of two parts, eases the installation of system  20  on most existing vehicles without reducing the level of protection to solenoid  1  provided by armored encapsulation  26 .  
         [0127]     Second part  1012  is manufactured compatible with first part  1011  so that once first part  1011  is covered by second part  1012 , armored encapsulation  26  is essentially a complete, unopenable, unit. The compatibility between first  1011  and second  1012  parts may be achieved, for example, by manufacturing armored encapsulation  26  with at least one positioning pairs such as, but not limited to, a pin  1023  (say, on second part  1012 ) and a compatible groove  1013  (say, on first part  1011 ). The number of positioning pairs determines the number of predetermined angles at which second part  1012  may be rotated relative to first part  1013 . Alternatively, the compatibility between first  1011  and second  1012  parts may be achieved by gluing, welding, joining by pressing or using any other known method to attach second part  1012  to first part  1011 , once correctly positioned.  
         [0128]     According to a preferred embodiment of the present invention first part  1013  may comprise an additional opening  104  to accommodate close-fit installations in cases where solenoid  1  is close to or touches the starter motor  2 .  
         [0129]     The cylindrical shape of armored encapsulation  26  shown in  FIG. 3  is further advantageous in that it makes it more difficult to grip by a tool. Thus, armored encapsulation  26  either remains closed or the level of control by the thief is reduced, inflicting irreversible damage and malting it difficult for him to use skill in order to overcome the system. In the latter case “S” terminal  201  (or any other appropriate terminal, such as, but not limited to, “B” terminal  202  or “M” terminal  203 ) is substantially damaged thereby rendering solenoid  1  useless.  
         [0130]      FIG. 4   a - b  is a more detailed illustration of system  20  and solenoid  1 . In particular,  FIG. 4   a - b  shows relative locations and connection between the various parts of system  20  and solenoid  1 , according to a preferred embodiment of the present invention. One or more elongators are used to define an inner volume for circuit  105  so as to avoid electric shortcuts, while maintaining compatibility with the original wiring of the vehicle.  
         [0131]     Two such elongators are shown in  FIGS. 4   a - b , designated as elongator  204  and elongator  205 . The elongators (e.g., elongators  204  and  205 ) are preferably sizewise compatible with circuit  105  and, in addition, geometrically compatible with terminals  202  and  203  of solenoid  1 , so that circuit  105 , the elongators, terminals  202 / 203  and armored encapsulation  26  form a substantially compact assembly.  
         [0132]     With reference to  FIG. 4   b , the elongators are preferably manufactured with an internal thread  2211 , designed to be compatible with terminals  202  and  203  of solenoid  1 , and an external thread  2212 , designed to match the original power wires such as power line  711  and nuts and at least one security nut (e.g., two security nuts, designated  206  and  207 ), as further detailed hereinafter. In case terminals  202  and  203  are differently shaped, internal thread  2211  is shaped in accordance with its respective terminal. Elongators  204  and  205  are preferably made of a combination of a conductive part  221  and an insulating part  222 . Conductive part  221  is preferably adjacent to thread  2211  whereas insulating part  222  is preferably on the other side of elongators  204  and  205 . Insulating part  222  serves for avoiding electrical contact between armored encapsulation  26  and conductive parts  221  and/or terminals  202  and  203 . Preferably, conducting part  221  is shaped to correspond to its respective terminal ( 202  or  203 ) so as to facilitate the connection of the original vehicle electric contacts (not shown) to elongators  204  and  205  without the need for further modification of integral parts of the vehicle.  
         [0133]     Openings  102  of armored encapsulation  26  (see also  FIG. 3   a - b ) preferably match the size and shape of elongators  204  and  205 . Preferably, armored encapsulation  26  is manufactured with an additional opening  103  (see also  FIG. 3   b ) through which wires  211  and  213  (or RF antenna) may be routed. According to a preferred embodiment of the present invention, opening  103  is so located on armored encapsulation  26  so as to prevent any access to circuit  105  through opening  103 .  
         [0134]     Security nuts  206  and  207  are used to fix armored encapsulation  26  into position, so as to prevent future attempts at removal. One way of achieving such an effect is to select as security nuts  206  and  207  of a kind which may not be reopened once screwed onto elongators  204  and  205 .  
         [0135]      FIGS. 4   c - d  are schematic illustrations of security nuts  206  and  207 , according to a preferred embodiment of the present invention. Each one of security nuts  206  and  207  may comprise three parts: a first part  302 , designed as a regular shell of a screw nut, so as to withstand a predetermined maximal tightening force; a second part  304 , designed to withstand predetermined maximal shear forces; and a third part  306  designed to prevent reopening using a conventional opening tool. First  302  second  304  and third  306  parts are preferably concentric and may be arranged either radially ( FIG. 4   c ) or axially ( FIG. 4   d ).  
         [0136]     First part  302  serves for allowing the respective security nut to be mounted, and tightened, in one embodiment using a conventional tool, and in another embodiment using a special tool. Second part  304  is preferably manufactured sufficiently thin so that a shear force higher than the predetermined maximal shear forces results in breaking of second part  304  and detachment of first part  302  therefrom. Third part  306  is the part that remains on elongator  204  and  205 . Preferably, third part  306  is essentially round (e.g., spherical, cylindrical, conical) and is sufficiently small so that a conventional tool slips off upon a reopening attempt.  
         [0137]     Thus, once armored encapsulation  26  is positioned so that threads  2212  protrude through openings  102 , security nuts  206  and  207  are tightened thereon. Then, the installer ensures that the system operates and properly mounted and tightens security nuts  206  and  207  forcibly, exceeding the maximal tightening force. The high shear force resultant in breaking of second part  304  and detachment of the first part  302  from the third part  306 , thereby preventing reopening of armored encapsulation  26 .  
         [0138]     According to a preferred embodiment of the present invention, security nuts  206  and  207  may be shaped so that the installation is not completed until first part  302  is detached from third part  306 , thereby ensuring a correct installation procedure. This may be achieved, for example, by selecting the combined longitudinal dimension of first part  302  and second part  304 , so that security nuts  206  and  207  encapsulate external thread  2212  of elongators  204  and  205 . Alternatively, external thread  2212  may be integrated with third part  306 , which thus can be is accessible only after first  302  and second  304  have been detached. In this alternative, elongators  204  and  205  matches the security nuts, but not the size required for installation of the electric wires.  
         [0139]     As stated, external thread  2212  is designed to match the original power wires (e.g. line  711 ) and nuts of the vehicle, hence, the temporarily encapsulation of external thread  2212  causes malfunctioning in the system or the solenoid. Only once the installer applies the required force and breaks second part  304  thread  2212  is revealed and the installation procedure can be continued (e.g., by re-connecting the original wires of the vehicles thereto).  
         [0140]     Reference is now to  FIG. 5 , which is a more detailed illustration of system  20  and solenoid  1 , according to a preferred embodiment of the present invention, in which system  20  further comprises a locking device  110 , for allowing reopening of armored encapsulation  26  by an authorized person, e.g., for maintains or repair purposes. Locking device  110  may be any known locking device, for example a key-based lock cylinder having a keyhole  112  or a password-based electrical locking device. The advantage of this embodiment is that the authorized person can access the interior of armored encapsulation  26  without the need for destructive actions. In this embodiment, armored encapsulation  26  is preferably formed with an additional opening  106 , designed to match the inner shape of locking device  110  and to facilitate opening and closing of locking device  110 , e.g., by entering a pre-programmed password or by using a key  113  designed compatible to keyhole  112 .  
         [0141]     Specifically, according to one embodiment, when locking device  110  is in a predetermined position, a locking element  111 , connected to locking device  110 , engages a lock hole  1031  positioned in a mounting plate  107 , and thereby mounts armored encapsulation  26  to solenoid  1 . Mounting plate  107  may be connected to the terminals  202  and  203 , to elongators  204  and  205  or to the body of solenoid  1 . Mounting plate  107  is preferably manufactured with two holes  1030  each compatible with one of elongators  204  and  205 . Alternatively, circuit  105  may serve as mounting plate  107 . In this alternative, lock hole  1031  is preferably formed in circuit  105 . The advantage of using circuit  105  as the mounting plate is that if locking device  110  is forcibly attacked circuit  105  is damaged beyond immediate repair.  
         [0142]     The present embodiments successfully address the rare possibility of system failure and provide an optional bypassing procedure to allow starting of the vehicle, e.g., in case of emergency or malfunction of user interface device  28 . Hence, according to a preferred embodiment of the present invention, locking device  110  may also serve for bypassing control apparatus  22 . For example, an additional electrical wire may be routed from an electrical switch controlled by locking device  110  to first end  212  (see  FIGS. 2   a - b ). Thus, locking device  110  may be used (e.g., using key  113 ) to establish contact between first end  211  and second end  212  thereby to bypass circuit  105 .  
         [0143]     It is to be understood that circuit  105  may be bypassed also in embodiments in which locking device  110  is not included, e.g., using a bypassing device which is connected similarly to locking device  110 . In this embodiment, the bypassing device is preferably equipped with an appropriate mechanical or electrical recognition utility, as further detailed hereinabove.  
         [0144]     The operation of the starter may also be controlled by positioning control apparatus  22  within solenoid  1 , so that the original solenoid housing serves as armored encapsulation  26 .  
         [0145]     Reference is now made to  FIG. 6  and  FIG. 7 , which are schematic illustrations of the complete starter assembly ( FIG. 6 ) and of the interior portion of solenoid  1  ( FIG. 7 ). In principle, the operation of solenoid  1  is as follows. An internal plunger  902  is wound by two wires, a “hold-in” wire  924  and a “pull-in wire”  921 . Wire  924  (the “hold-in” wire) serves for holding internal plunger  902  in its position when the starter assembly is not in use. Internal plunger  902  is manufactured with a contact  903  which serves for closing an electrical circuit between “M” terminal  203  and “B” terminal  202 , when the starter assembly is in operation mode. Specifically, when an electric current flows through wire  921  (the “pull-in” wire), magnetic forces, generated in the volume defined by the windings of wire  921 , pull internal plunger  902  to establish an electrical contact between an internal contact  923  of “M” terminal  203  and an internal contact  922  of “B” terminal  202 . The electrical connection between “M” terminal  203  and “B” terminal  202  allows high electric current to flow to motor  2 , which starts to rotate. While moving towards contact  922  and  923 , internal plunger  902  pulls a mechanical shift lever  810  connected to shaft  21  via a clutch device  801 . Thus, simultaneously with the rotation of motor  2 , shaft  21  engages the engine shaft of the vehicle (not shown) generating the initial compression required for ignition or cranking thereof.  
         [0146]     According to a preferred embodiment of the present invention control apparatus  22  is designed and constructed to control motion of lever  810  so that when system  20  is operative the engagement between shaft  21  and the engine&#39;s shaft is prevented. Alternatively, control apparatus  22  may be designed and constructed to control motion of an internal plunger  902  of solenoid  1 . It will be appreciated that when internal plunger  902  is disabled, lever  810  and shaft  21  are also immobilized and therefore, even if a thief successfully interconnects terminals  202  and  203  (e.g., by an external current bridge), no initial ignition/cranking can occur. The control of the motion of internal plunger  902  may be done either mechanically or electrically, as further explained hereinbelow.  
         [0147]     Hence, in one embodiment, control apparatus  22  comprises an electrical switch  910  which controls electrical signals transmitted through wire  921  and/or wire  924 . In this embodiment, the motion of internal plunger  902  is prevented either by keeping the current flowing through wire  924  (the “hold-in” wire) thereby holding internal plunger  902  in its non-operative position, or by preventing current from flowing through wire  921  (the “pull-in” wire) thereby preventing the generation of magnetic forces in the direction of contact  922  and  923 .  
         [0148]     Thus, control apparatus  22  preferably comprises an electronic circuit  905  controlling a switch  910  positioned on a wire  901  connecting wire  921  and/or wire  924 . Circuit  905  may also be in communication with user interface device  28 , so as to allow the authorized user to activate or deactivate control apparatus  22  as described hereinabove.  
         [0149]     Reference is now made to  FIG. 8 , which is a schematic illustration of the interior portion of solenoid  1  and system  20  in another embodiment in which a mechanical actuator  911  is used for controlling the motion of internal plunger  902 . Hence, one alternative of this embodiment may be, for example, the use of a mechanical actuator  911  manufactured with a mechanical stopper  912 , (e.g., a pin or a lever). Thus, control apparatus  22  preferably comprises mechanical actuator  911 , mechanical stopper  912  and electronic circuit  905 . In use, mechanical actuator  911  is controlled by electronic circuit  905  so that when the authorized user chooses to activate control apparatus  22 , mechanical actuator  911  and stopper  912  limit the motion of internal plunger  902 , thereby preventing the initial ignition/cranking of the engine by an unauthorized user.  
         [0150]     Another alternative for mechanical control of the motion of internal plunger  902  may be the use of an elongation rod  904  connected to internal plunger  902  and a compatible blocking mechanism  915 . According to a preferred embodiment of the present invention elongation rod  904  and its compatible blocking mechanism  915  are designed and constructed so as to selectively limit the motion of internal plunger  902 . This may be done, for example, by selecting blocking mechanism  915  to have asymmetric height or width, so that the position and/or orientation of blocking mechanism  915  determines the nature (e.g., the amplitude) of motion of internal plunger  902 . Specifically, when blocking mechanism  915  is in one position (say, “right” position, see  FIG. 8 ), the motion of internal plunger  902  is limited and when blocking mechanism  915  is in another position (“left” position) the motion of internal plunger  902  is allowed. Other positions and/or orientations of blocking mechanism  915  are also not excluded from the scope of the present invention.  
         [0151]     When the motion of internal plunger  902  is limited, no electrical contact is established between contacts  903 ,  923  and  922  and no ignition/cranking occurs. The change in position/orientation of blocking mechanism  915  may be achieved, for example, by a mechanical actuator  914  which, similarly to actuator  911 , may be controlled, e.g., by electronic circuit  905 . Additionally, and preferably, circuit  905  may be in communication with user interface device  28 , as further detailed hereinabove.  
         [0152]     The optional bypassing procedure mentioned hereinabove may also be employed in the embodiments in which the control apparatus limits the motion of internal plunger  902  or lever  810 . Hence, according to a preferred embodiment of the present invention the bypassing device (which, as stated, may be realized by locking device  110 ) may disable any of the above mechanisms which limit the motion of internal plunger  902  or lever  810  (e.g., switch  910  mechanical actuator  911  or blocking mechanism  915 ).  
         [0153]     As stated, essential module  24  may be any of the vehicle systems which is essential for the mobilization of the vehicle. According to a preferred embodiment of the present invention the essential module may be power-supply unit  4 . In this embodiment, control apparatus  22  is designed and constructed so as to control the voltage of power-supply unit  4 . It is appreciated, that a complete disablement of power-supply unit  4  may harm systems in the vehicle, such as emergency sub-systems logic processors memory units and the like. Thus, according to a preferred embodiment of the present invention, the number of disabled electrolytic cells is selected so as to prevent initial ignition or cranking of the engine on the one hand, while maintaining sufficient power for all other electrical functions on the other hand.  
         [0154]     Reference is now made to  FIGS. 9   a - c , which are schematic illustrations of system  20  in the preferred embodiment in which control apparatus  22  controls power-supply unit  4 . Referring to  FIG. 9   a , in a typical ignition circuit, power-supply unit  4  has a grounded terminal  403  and a “B” terminal  402  of power-supply unit  4  which is connected via a power line  711  to “B” terminal  202  of solenoid  1 . Power line  711  is controlled by ignition switch  3 . The potential difference between terminal  403  and terminal  402  is typically about 12, 24 or 42 volts, depending on the type of the vehicle, but other voltage values are not excluded.  
         [0155]     As used herein the term “about” refers to ±10%.  
         [0156]     Referring to  FIG. 9   b , according to a preferred embodiment of the present invention control apparatus  22  comprises a bypassing circuit  710  which bypasses a selective number of electrolytic cells of power-supply unit  4 . Bypassing circuit  710  is preferably controlled by circuit  105 , which, in common with the other embodiments, preferably communicates with user interface device  28 .  
         [0157]     The interior of power-supply unit  4  and bypassing circuit  710  are better illustrated in  FIG. 9   c . For simplicity,  FIG. 9   c  shows six electrolytic cells of power-supply unit  4 . However, the presently preferred embodiment may be applied on any number of electrolytic cells. Hence, of the six electrolytic cells, one electrolytic cell, designated  722 , is bypassed while the remaining five electrolytic cells, designated  720 , are not bypassed. Cell  722  is preferably bypassed by a semiconductor component, e.g., a diode  713  so as not to cause damage to power-supply unit  4 . Bypassing circuit  710  comprises a relay  724  which toggles between a state in which cell  722  is bypassed and a state in which cell  722  is not bypassed. Bypassing circuit  710  may be either connected directly to terminal  402 , or, alternatively, an additional wire  712  may be connected to power line  711 . In any case, once cell  722  is bypassed, the voltage of power-supply unit  4  drops by the ratio between the number of bypassed cells to the total number of cells (about 17% in the example of  FIG. 9   c ). If, for example, the regular voltage of power-supply  4  is 12 volt, in a bypassing state the voltage drops to about 10 volts. Such reduced voltage is sufficient for retaining the functionality of most electronic sub-systems, but does not provide sufficient power to operate the starter motor.  
         [0158]     It is to be understood that the above description is for illustrative purpose and that the present embodiment can be applied with suitable adaptation to other kinds of power-supply unit. For example, the automotive vehicle industry has recently shown a tendency to move from a complex electrical sub-system to a simpler and more efficient power-net topology based on 36-42 volt nominal voltages distributed from central bus bars. As the different nominal voltage systems are expected to display similar electrical behavior as the traditional legacy systems, the present embodiment can be employed also on these systems, using proportionally higher voltage levels. Other power-supply units are based on super capacitors. The present embodiment can be employed on these systems, e.g., using two capacitors parallel, where one of which is selectively disconnected while the other continues to supply minimal power.  
         [0159]     With reference to  FIG. 10 , according to a preferred embodiment of the present invention power line  711  may be externally protected, e.g., by an armored sleeve  412  encapsulating power line  711  and/or an armored cap  411  encapsulating terminal  402 . Additionally, as stated, self-destructing assembly  23  may be positioned in the interior of power-supply  4  so that any attempt to open power-supply  4  and bypass control apparatus  22  results in substantial damage beyond immediate repair.  
         [0160]     According to another aspect of the present invention there is provided a method of installing a theft-preventing system. The method comprises the following method steps which are illustrated in the flowchart of  FIG. 11 .  
         [0161]     Referring to  FIG. 11 , in a first step a control apparatus is provided and positioned so as to control operation of the essential module of the vehicle. The control apparatus may be, for example, similar to control apparatus  22 . In a second step of the method, the control apparatus is encapsulated using at least one armored encapsulation (e.g., armored encapsulation  26 ). According to a preferred embodiment of the present invention the method may further comprise an additional step in which a self-destructing assembly is positioned within the armored encapsulation. The self-destructing assembly is arranged so that even if the armored encapsulation is only partially damaged, the self-destructing assembly disintegrates and disables the essential module. The self-destructing assembly may be any assembly which irretrievably disintegrates upon violent action, e.g., self-destructing assembly  23  as described hereinabove.  
         [0162]     In addition, the method may further comprise another step in which a user interface device is configured to electrically communicate with the control apparatus, e.g., using a communication device, as further detailed hereinabove.  
         [0163]     In addition, the method may comprise a step of locking the armored encapsulation using a locking device, so as to allow a removal of at least a part of the armored encapsulation solely by an authorized person.  
         [0164]      FIG. 12  is a flowchart of a method of preventing theft of a vehicle according to an additional aspect of the present invention. The method comprises selectively preventing motion of an internal plunger of the solenoid, thereby preventing initial ignition of the vehicle. As stated, the motion of the internal plunger is essential for starting the vehicle. Thus, upon a legitimate starting of the vehicle (e.g., using an ignition key, a valid code, etc.), the motion of the internal plunger is allowed so that shaft  21  engages a compatible shaft in the vehicle&#39;s engine (see  FIG. 3 ). On the other hand, under circumstances interpreted as suspicious, the motion of the internal plunger is prevented, electrically or mechanically, as further detailed hereinabove. The allowance or disallowance of the motion of the internal plunger may be achieved, for example, using a user interface device (e.g., user interface device  23 ). In addition, according to a preferred embodiment of the present invention, the motion of the internal plunger may be irreparably disabled, if an attempt is made to attack the system.  
         [0165]     Similarly to the above method, this method may comprise an optional step in which an armored encapsulation of the solenoid is locked using a locking device, so as to allow a removal of at least a part of the armored encapsulation solely by an authorized person.  
         [0166]     It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable subcombination.  
         [0167]     Although the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims. All publications, patents and patent applications mentioned in this specification are herein incorporated in their entirety by reference into the specification, to the same extent as if each individual publication, patent or patent application was specifically and individually indicated to be incorporated herein by reference. In addition, citation or identification of any reference in this application shall not be construed as an admission that such reference is available as prior art to the present invention.