Claims:We Claim:
1. An anti-theft device (10) for a component (12), said device (10) comprising :
- a breaking circuit (14);
- a cable (18) routed through said component (12), said cable (18) connecting said breaking circuit (14) and a power source (20), and
- a control unit (16) connected to said breaking circuit (14), said control unit (16) adapted to detect removal of said component (12) when said cable is cut-off.

2. The anti-theft device (10) as claimed in claim 1, wherein said control unit (16) adapted to generate a warning signal upon detection of a variation in an output of said breaking circuit (14).

3. The anti-theft device (10) as claimed in claim 1, wherein said breaking circuit (14) comprises at least one resistor (22) and a switch (24).

4. The anti-theft device (10) as claimed in claim 3, wherein said switch (24) is chosen from a group of switches comprising a transistor, a metal–oxide–semiconductor field-effect transistor (MOSFET), an insulated-gate bipolar transistor (IGBT).

5. The anti-theft device (10) as claimed in claim 1, wherein said cable (18) comprises an insulation cover arranged around said cable (18).

6. The anti-theft device (10) as claimed in claim 1, wherein said component (12) is chosen from a group of said components comprising an exhaust catalyst positioned in an exhaust pipe, an engine in a vehicle, at least one working component in a home automation system, an antique in a museum.

7. The anti-theft device (10) as claimed in claim 1, wherein said power source (20) is made as an internal component of said anti-theft device (10).

8. The anti-theft device (10) as claimed in claim 1, wherein said power source (20) is externally connected to said anti-theft device (10).
, Description:Complete Specification:
The following specification describes and ascertains the nature of this invention and the manner in which it is to be performed.
Field of the invention
[0001] This invention relates to an anti-theft device.

Background of the invention
[0002] Various vehicle anti-theft devices are known which immobilize a vehicle and prevent the vehicle from being driven away by a thief even if the latter has gained entry to the interior of the vehicle. The theft of automotive vehicles, both private and commercial, is an ever-growing problem in our society. Even the development of sophisticated anti-theft devices such as vehicle alarms, chapman locks, steering wheel column locks, etc., has not stemmed the tide, because the sophistication of the thieves has advanced commensurately. Frequently, it takes a professional thief less than a minute to overcome any of the currently available antitheft devices.

[0003] A Prior art document US4903510 discloses a vehicle antitheft device for locking the brakes of a vehicle including a hook member which engages the brake pedal of a vehicle. The hook member is locked through the floorboard which slides through a guide hole in a locking sleeve which depends from the floorboard .A brake light cutoff switch is included to prevent brake light operation when the device is in the locked position. A metal box encloses the locking mechanism to protect the system from tampering from underneath the vehicle.

Brief description of the accompanying drawing
[0004] Different modes of the invention are disclosed in detail in the description and illustrated in the accompanying drawing:
[0005] Fig.1 illustrates an anti-theft device for a component, in accordance with an embodiment of the invention, and
[0006] Fig.2 illustrates the anti-theft device in a vehicle, in accordance with an embodiment of the invention.

Detailed description of the embodiments
[0007] Fig.1 illustrates an anti-theft device for a component, in accordance with one embodiment of the invention. The anti-theft device 10 comprises a breaking circuit 14 and a control unit 16 connected to the breaking circuit 14. The device 10 further comprises a cable 18 that is routed through the component 12. The cable 18 connects the breaking circuit 14 and a power source 20. The control unit 16 adapted to detect removal of the component 12 when the cable 18 is cut-off.

[0008] Further the construction of the anti-theft device and the components of the anti-theft device are explained. The breaking circuit 14 comprises at least one resistor 22 and a switch 24. According to one embodiment of the invention, the breaking circuit 14 comprises two resistors (22(a), 22(b)) connected in parallel, to the power source 20 and the switch 24 connected to one of the resistors 22(a)/22(b) in series. For instance, the two resistors (22(a), 22(b)) are referred as a first resistor 22(a) and a second resistor 22(b). The first resistor 22(a) is connected between the power source 20 and the control unit 16 and the second resistor 22(b) connected to the first resistor 22(a) and to a base terminal of the switch 24. The switch 24 is connected between the second resistor 22(b) and the control unit 16. In addition to this, the cable 18 is connected from the power source 20 routing through the component 12 and back to a ground terminal 28 of the power source 20.

[0009] For example, if the component 12 is an exhaust catalyst 30 in an exhaust pipe 32 (as shown in figure 2), the cable 18 from the exhaust pipe 32 is connected to the switch 24 and to the ground terminal 28 of the power source 20. This arrangement works as a short circuit loop. During the normal working conditions of the control unit 16, the cable 18 short circuits the switch 24 base and the emitter terminals, which results in a zero charge at a collector terminal. Due to the zero charge at the collector terminal of the switch 24, the control unit 16 does not receive any signal.
[0010] Upon detecting the removal of the component by cutting the cable 18, the current/voltage flows through the collector terminal of the switch 24, that provides a signal to the control unit 16 about the change of the output voltage/current. The switch 24 is chosen from a group of switches comprising a transistor, a MOSFET, an IGBT and the like. According to one embodiment of the invention, the switch 24 is a single pole single throw switch, which is used to perform an ON/OFF operation of the device 10. However, the type of the switch is not limited to the above –disclosed types, but can be any switch that is known to a person skilled in the art.

[0011] According to one embodiment of the invention, the cable 18 comprises an insulation cover arranged around the cable 18 along the length of the cable 18 for protecting the cable 18 from the harsh environments like excessive heat or cold temperatures. According to another embodiment of the invention, the cable 18 is made of temperature resistant material that can withstand an excessive heat or excessive cold. The cable 18 is a conductive cable as known in the state of the art and is made of elements like copper, aluminum, zinc etc., According to one embodiment of the invention, the cable 18 is routed through the component 12 using at least one fitting techniques comprising a snap fit, a screw fit, a fastener and the like.

[0012] The control unit 16 as disclosed in this invention is chosen from a group of control units comprising a microprocessor, a microcontroller, a digital circuit, an integrated circuit and the like. According to one embodiment of the invention, the power source 20 is a battery. In one arrangement, the power source 20 is connected externally to the anti-theft device 10 and in another arrangement, the power source 20 is made as an internal component of the device 10. In the example explained above, the component 12 being the exhaust catalyst 30 in the exhaust pipe 32, the power source 20 is a vehicle battery and the control unit 16 is any of the vehicle electronic control unit.

[0013]The component 12 as claimed in the invention is chosen from a group of components comprising an exhaust catalyst positioned in an exhaust pipe, an engine in a vehicle, at least one working component in a home automation system like a safety locker, an antique piece in a museum and the like. The above-disclosed anti-theft device 10 can be used in all the places where the valuable items are need to be secured from the theft.

[0014] The control unit 16 generates a warning/alarm signal upon detecting the removal of the component 12 from the system. The warning/alarm is chosen from any one of the following alarms comprising an audio signal or a video signal. In addition to this, the control unit 16 transmits a message to a communication device 26 of the user of the component 12 regarding the theft using at least one communication means. The communication means is a wireless communication means comprising a WIFI, Bluetooth, cellular netwroks and the like.

[0015] A method of working of the anti-theft device 10 is explained. During a normal operating condition, the voltage/ current from the power source 20 (battery) is supplied to the cable 18 via the second resistor 22(b) and the cable 18 to the ground. In this kind of arrangement, the current is circulated in a closed loop (power source 20- second resistor 22(b)- cable 18- ground terminal 28). The control unit 16 receives the power from the battery 20 via the first resistor 22(a). When the current flows in the cable 18, the control unit 16 detects a predefined voltage value at the switch 24, as the switch 24 is in the closed condition. In one instance, the predefined voltage is zero.

[0016] When the cable 18 is cut-off from the circuit 14 to remove the component 12 from the system, the voltage at the switch 24 is varied. The switch 24 is in the conductive state in connection with the control unit 16. Upon detecting the voltage more than the predefined value at the switch 24, the control unit 16 detects the removal of the component 12 and the cable 18 being cut-off. The control unit 16 generates an alarm/warning signal to alert the user of the component 12 about the theft/removal of the component 12.

[0017] As disclosed above, the component 12 is an exhaust catalyst 30 present in an exhaust pipe 32 of a vehicle as shown in the figure 2. The exhaust catalyst 30 can be removed by cutting off from the exhaust pipe 32. In order to avoid these kind of thefts, the present invention provides a cost-effective solution. The cable 18 is routed through the exhaust catalyst 30 and is connected between the power source 20 and the ground terminal 28 of the power source 20 as explained above.

[0018] When the exhaust catalyst 30 is removed from the exhaust pipe 32, the cable 18 routed through the exhaust catalyst 30 is disconnected from the power source 20. The control unit 16 detects an output voltage at the switch 24 more than the predefined voltage when the cable 18 is cut-off from the circuit. The control unit 16 generates an alarm/warning signal to the user of the vehicle regarding the removal of the exhaust catalyst 30 from the exhaust pipe 32.

[0019] With the above-disclosed device 10, the user of the component 12 is intimated about the theft of the component 12 in the real-time. The cable 18 is positioned in the component 12 in such a way that, the cable 18 is not visible to the unauthorized person. The theft of the components 12 is avoided in an efficient way by using the above-disclosed device. The power source 20 is arranged in such a way that, the source 20 powers the control unit 16 even if the system is switched OFF. For example as disclosed above, the anti-theft device 10 receives power from the vehicle battery even when the vehicle is in OFF state.

[0020] It should be understood that embodiments explained in the description above are only illustrative and do not limit the scope of this invention. Many such embodiments and other modifications and changes in the embodiment explained in the description are envisaged. The scope of the invention is only limited by the scope of the claims.