JPH0995216A - Vehicular theft prevention device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To excute trouble diagnosis by corresponding to an immobilizer control part simply without the installation of a new port for communication, utilizing the communication protocol for trouble diagnosis on a software, quicken a communication speed and using the immobilizer control part and the trouble diagnosis part commonly. SOLUTION: The characteristic of this invention is that an ignition key 4, a coil unit 6, an immobilizer control part 8 and an engine control part 10 are installed and a trouble diagnosis part 28 which is a master on a communication method for this engine control part 10 is installed connectingly by a communication circuit 30 for trouble diagnosis and the immobilizer control part 8 which is a master on a communication method for the engine control part 10 is installed connectingly to a communication circuit 30 for trouble diagnosis by a communication circuit 32 for immobilizer. The trouble diagnosis part 30 is installed by interposing an always close type relay 36 released at the communication time to the engine control part 10 by the immobilizer control part 8 on the way of a circuit 34 for electric source.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anti-theft device for a vehicle, and more particularly, it is not necessary to provide a new communication port in the engine control unit, and the cost can be reduced. Can correspond to
The communication protocol for failure diagnosis can be used in software to save development work, the communication speed can be increased by using the communication port, and the communication between the immobilizer control section and the failure diagnosis section. The present invention relates to an anti-theft device for a vehicle, which can share a line without inviting interference and can perform failure diagnosis even when an immobilizer control unit is removed or a failure occurs.

[0002]

2. Description of the Related Art Some vehicles are provided with a vehicle antitheft device for the purpose of preventing theft by unauthorized unlocking. The vehicle anti-theft device is provided with a coil unit that outputs an identification code by inserting an ignition key and rotating the ignition key to a starting position, and an immobilizer control unit that is an anti-theft control unit that determines whether the ignition key is correct. Some include an engine control unit that continues driving the engine when an engine drive permission signal indicating that the key is a regular ignition key is input from the immobilizer control unit within a set communication time from the start of rotation by rotating the key. .

An example of such a vehicle antitheft device is:
JP-A-63-93649, JP-A-6-27076
No. 4 and Japanese Patent Application Laid-Open No. 7-69173.

The device disclosed in Japanese Patent Laid-Open No. 63-93649 transmits and receives information for driving an engine by magnetically coupling a lock-side annular core and a key-side shaft-shaped core to each other. When the information of (1) matches the information of the lock side, the engine is allowed to start.

The device disclosed in Japanese Patent Laid-Open No. 6-270764 includes a key unit consisting of a key and a lock, a key detection circuit and an engine control circuit, and a plurality of communication lines between the key detection circuit and the engine control circuit. The engine control circuit starts the engine when the engine start permission signal is input to any of the plurality of communication lines, and when the plurality of communication lines are disconnected, measures the time interval of disconnection to determine whether the signal is stolen. It is to judge whether or not.

The device disclosed in Japanese Patent Laid-Open No. 7-69173 outputs an engine start permission signal only for a certain period of time when a key inserted in a cylinder rotates in the starter direction.

[0007]

By the way, a coil unit for outputting an identification code by inserting the ignition key and rotating it to the starting position is provided, and an immobilizer control section for determining whether the ignition key is correct or not is provided. In the vehicle anti-theft device provided with an engine control unit that continues to drive the engine when an engine drive permission signal that is a regular ignition key is input from the section, the immobilizer control unit and the engine control unit Communication is performed between them by a dedicated communication line.

That is, as shown in FIG. 4, a conventional vehicle antitheft device 102 is provided by connecting an immobilizer control unit 104 and an engine control unit 106 by a dedicated immobilizer communication line 108. Communication is performed through the communication line 108. Further, the engine control unit 106 is provided with a failure diagnosis unit 110 for failure diagnosis connected by a failure diagnosis communication line 112. The respective communication lines 108 and 112 are connected to the engine control unit 106.
Of communication ports (not shown).

However, when the communication port is used, the number is limited by the arithmetic processing unit (CPU) used in the engine control unit 106. Therefore, when the communication ports are used for engine failure diagnosis, engine control unit failure diagnosis, and the like, in order to connect the immobilizer communication line 108, one of the failure diagnosis communication lines is used. Must be deleted.

In such a case, providing a new communication port in order to connect the immobilizer communication line 108 has the disadvantage of increasing the cost. Further, if the immobilizer communication line 108 is connected to the general-purpose port without being connected to the communication port, the communication speed may be lowered.

When the immobilizer communication line 108 and the failure diagnosis communication line 112 are shared, the immobilizer control unit 104 and the failure diagnosis unit 110 may communicate with the engine control unit 106 at the same time. In this case, there is an inconvenience that normal communication cannot be performed due to interference.

[0012]

Therefore, in order to eliminate the above-mentioned inconvenience, the present invention provides an ignition key equipped with a transponder, and inserts the ignition key and rotates the transponder to a starting position to supply power to the transponder. A coil unit that supplies the identification code and outputs the identification code is provided. When the identification code input from the coil unit is positive, an engine drive permission signal is output and when the identification code is negative, the engine is output. An immobilizer control unit that outputs a drive prohibition signal is provided, and the engine is driven when the engine drive permission signal is input from the immobilizer control unit within a set communication time from the start of rotation by turning the ignition key to the start position. Provide an engine control unit to continue and connect to this engine control unit. Provided in connection with a communication line for fault diagnosis and fault diagnosis portion serving as a master on the communication system Te,
The engine control unit is provided by connecting the immobilizer control unit serving as a master in a communication system to the failure diagnosis communication line through an immobilizer communication line, wherein the failure diagnosis unit is a power supply line. In the middle of the above, a normally-closed relay that is opened during communication with the engine control unit by the immobilizer control unit is interposed.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The vehicle antitheft apparatus of the present invention is provided with an ignition key, a coil unit, an immobilizer control section and an engine control section, and a failure diagnosis which is a master in a communication system with respect to the engine control section. The control section is connected to the engine control section via the failure diagnosis communication line, and the immobilizer control section, which is the master of the communication method for the engine control section, is connected to the failure diagnosis communication line via the immobilizer communication line. By
One communication port can be shared by the immobilizer control unit and the failure diagnosis unit without newly providing a communication port to which the immobilizer communication line is connected, and the communication of the immobilizer control unit can be performed. Since it is performed for a short time after the start of the engine, there is no possibility that the communication of the immobilizer control unit and the communication of the failure diagnosis unit overlap. In addition, this vehicle antitheft device is provided with a normally-closed relay that is released during communication with the engine control unit by the immobilizer control unit in the middle of the power supply line of the failure diagnosis unit. The power supply to the failure diagnosis unit can be shut off when the communication is performed, and the immobilizer control unit and the failure diagnosis unit can be prevented from communicating with the engine control unit at the same time.

[0014]

An embodiment of the present invention will be described below with reference to the drawings. 1 to 3 show an embodiment of the present invention. In FIG. 3, reference numeral 2 is a vehicle antitheft device. The vehicle antitheft device 2 includes an ignition key 4, a coil unit 6, an immobilizer control unit (theft prevention control unit) 8 and an engine control unit 10.

The ignition key 4 is provided with a key groove 12 and a transponder 14. The transponder 14 has a coil section and a code generating section (not shown), and is driven by the supply of power from the coil unit 6 to generate an identification code.

When the ignition key 4 is rotated to the starting position, the ignition circuit 22 is turned on and a starter switch (not shown) is turned on to drive a starter motor (not shown) as described later.

The coil unit 6 is provided with a coil portion 16 into which the ignition key 4 is inserted and rotated, and a coil circuit portion 18 connected to the coil portion 16.

The coil unit 16 is excited by being supplied with power from the coil circuit unit 18 by turning the inserted ignition key 4 to the starting position and turning on the ignition circuit 22. As a result, the coil section 16 electromagnetically couples the coil section of the transponder 4 to supply power, generate an identification code in the code generation section, and receive the identification code.

The coil circuit section 18 is connected to the immobilizer control section 8 and outputs the identification code received by the coil section 16 to the immobilizer control section 8.

The immobilizer controller 8 determines whether the identification code input from the coil unit 6 is correct. The immobilizer control unit 8 is connected to an engine accessory circuit 20 and an ignition circuit 22 which are not shown.

The immobilizer control section 8 outputs an engine drive permission signal to the engine control section 10 when the identification code input from the coil unit 6 is positive. The immobilizer control unit 8 outputs an engine drive prohibition signal to the engine control unit 10 when the identification code input from the coil unit 6 is negative.

The engine control unit 10 permits or prohibits starting of the engine in response to an engine drive permission signal or an engine drive inhibition signal input from the immobilizer control unit 8. The engine control unit 10 is connected with a fuel injection valve 24 and an ignition coil 26 of an engine (not shown), and when the ignition circuit 22 is turned on, the starter motor is driven and normal fuel injection and ignition are performed.

When the engine drive permission signal is input from the immobilizer control unit 8 within the set communication time from the start of the start by rotating the ignition key 4 to the start position, the engine control unit 10 controls the fuel injection by the fuel injection valve 24. The ignition by the ignition coil 26 and the ignition coil 26 are allowed, and the engine continues to be driven.

Further, the engine control unit 10 receives the engine drive prohibition signal from the immobilizer control unit 8 within a set communication time from the start of the start by the rotation of the ignition key 4 to the start position (when no signal is input). In addition, the fuel by the fuel injection valve 24 and the ignition by the ignition coil 26 are cut to prohibit the driving of the engine.

The vehicle antitheft device 2 is provided with a failure diagnosis unit 28. As shown in FIG. 1, the failure diagnosis unit 28 uses the failure diagnosis communication line 30 to connect the engine control unit 10 to the engine control unit 10.
Is connected to a communication signal port (not shown). The failure diagnosis unit 28 serves as a master in communication with the engine control unit 10. Therefore, the engine control unit 10 is a slave in the communication system with respect to the failure diagnosis unit 28.

Further, the immobilizer control unit 8 of the vehicle antitheft device 2 is used as a master in the communication system with respect to the engine control unit 10. The immobilizer control unit 8
The immobilizer communication line 32 is connected to the failure diagnosis communication line 30.

Further, in the vehicle antitheft device 2, as shown in FIG. 2, the failure diagnosis unit 28 is connected to the ignition circuit 22 by a power line 34. A normally closed relay 36 is provided in the middle of the power line 34. Relay 3
6 is connected to the immobilizer control unit 8 by a relay line 38. The relay 36 includes the immobilizer control unit 8
Thus, the opening operation is performed when the immobilizer control section 8 communicates with the engine control section 10, and the closing operation is performed when the immobilizer control section 8 completes the communication with the engine control section 10.

Next, the operation of this embodiment will be described.

In the vehicle antitheft device 2, when the ignition key 4 is inserted into the coil unit 6 and rotated to the starting position, the ignition circuit 22 is turned on and the starter motor is driven, fuel is injected and ignited. Start to start.

When the engine drive permission signal is input from the immobilizer control unit 8 within the set communication time from the start of the ignition key 4 starting to rotate to the starting position, the engine control unit 10 supplies the fuel supplied by the fuel injection valve 24. Ignition by the ignition coil 26 is allowed and the engine continues to be driven.

Further, the engine control unit 10 receives no engine drive prohibition signal from the immobilizer control unit 8 within a set communication time from the start of the ignition key 4 when the ignition key 4 is rotated to the start position, or neither signal is input. In this case, the fuel from the fuel injection valve 24 and the ignition from the ignition coil 26 are cut off to prohibit the driving of the engine.

In this vehicle antitheft device 2, the immobilizer communication line 32 is added to the existing failure diagnosis communication line 30.
By connecting with, the communication line of the immobilizer control unit 8 is interrupted by the communication line of the failure diagnosis unit 28.

In general, the failure diagnosis unit 28 is a master in the communication system with respect to the engine control unit 10, and the engine control unit 10 is a slave. By making the immobilizer control unit 8 the master in the communication method for the engine control unit 10 that is the slave in this manner, the immobilizer control unit 8 and the engine can be used by directly using the master-slave relationship at the time of failure diagnosis. Communication can be performed without changing the basic form of communication of the control unit 10.

In this way, the vehicle antitheft device 2
As shown in FIG. 1, the engine control unit 10 is provided with a failure diagnosis unit 28, which is a master in the communication system, connected by a failure diagnosis communication line 30, and is connected to the engine control unit 10 in the communication system. The immobilizer control unit 8 serving as a master is connected to the failure diagnosis communication line 30 by the immobilizer communication line 32.

As a result, the vehicle antitheft apparatus 2 does not provide a new communication port to which the immobilizer communication line 32 is connected to the engine control unit 10, but fails one communication port with the immobilizer control unit 8. Communication with the diagnosis unit 28 can be shared, and the communication of the immobilizer control unit 8 is performed for a short time after the start of the engine, so that the communication of the immobilizer control unit 8 and the failure diagnosis unit 28 can be performed. There is no risk of overlapping with communications.

Therefore, the vehicle antitheft device 2 is
It is not necessary to provide a new communication port in the engine control unit 10, and it is possible to easily support the immobilizer control unit 8 on hardware and software. Since it is not necessary to provide a new communication port, the cost can be reduced, Since the communication protocol for failure diagnosis above can be used, the effort for development can be saved, and the communication port for failure diagnosis is used without using the general-purpose port, so the communication speed can be improved. You can speed it up.

Moreover, in the vehicle anti-theft device 2, since the communication of the immobilizer control unit 8 and the communication of the failure diagnosis unit 28 are not likely to overlap with each other, the immobilizer control unit 8 is not affected.
And the failure diagnosis unit 28 can be shared without causing communication interference.

As shown in FIG. 2, the vehicle anti-theft device 2 is opened during the communication with the engine control unit 10 by the immobilizer control unit 8 in the middle of the power supply line 34 of the failure diagnosis unit 28, and the immobilizer is opened. A normally closed relay 36 is provided which is closed when the control unit 8 completes communication with the engine control unit 10.

As a result, this vehicle antitheft device 2
When the immobilizer control unit 8 communicates, the immobilizer control unit 8 and the fault diagnosis unit 28 can synchronize with the engine control unit 10 by interrupting the power supply to the fault diagnosis unit 28 to prohibit the operation. Can be prevented from communicating with.

Therefore, the vehicle antitheft device 2 is
The communication line between the immobilizer control unit 8 and the failure diagnosis unit 28 can be shared while avoiding the interference of the communication between the immobilizer control unit 8 and the failure diagnosis unit 28.
Even when the immobilizer control unit 8 is detached or when there is a failure, the power can be supplied to the failure diagnosing unit 28, so that the failure diagnosis can be performed.

[0041]

As described above, in the vehicle antitheft device of the present invention, the engine control unit is provided with a failure diagnosis unit which is a master in the communication system and is connected to the engine control unit through a failure diagnosis communication line. By providing the immobilizer control unit, which is the master of the communication method for the engine control unit, to the failure diagnosis communication line via the immobilizer communication line, a new communication port to which the immobilizer communication line is connected has been added. One communication port can be shared for communication between the immobilizer control unit and the failure diagnosis unit without being provided in the above, and the communication protocol for the failure diagnosis can be used in software. Communication is performed for a short time after the start of the engine, so that communication between the immobilizer control section and communication between the failure diagnosis section are performed. Bet is there is no risk that overlaps.

For this reason, the antitheft device for a vehicle does not need to provide a new communication port in the engine control unit, can easily correspond to the immobilizer control unit in hardware and software, and has a new communication port. Since it is not necessary to provide it, the cost can be reduced, and the communication protocol for failure diagnosis can be used in software, which saves development work and communication for failure diagnosis without using a general-purpose port. Since the communication port is used, the communication speed can be increased, and the communication of the immobilizer control unit and the communication of the failure diagnosis unit do not overlap, so
The immobilizer control unit and the failure diagnosis unit can be shared without causing communication interference.

Further, this vehicle anti-theft device is provided with a normally-closed type relay which is released during communication with the engine control section by the immobilizer control section in the middle of the power line of the failure diagnosis section. The communication line between the immobilizer control unit and the failure diagnosis unit can be shared while avoiding interference, and the failure diagnosis can be performed even when the immobilizer control unit is disconnected or when there is a failure.

[Brief description of drawings]

FIG. 1 is a block diagram in which a communication line of an immobilizer control unit is interrupted by a communication line of a failure diagnosis unit of a vehicle antitheft device according to an embodiment of the present invention.

FIG. 2 is a block diagram in which a normally-closed relay is provided in a power supply line of a failure diagnosis unit of a vehicle antitheft device according to an embodiment of the present invention.

FIG. 3 is a circuit configuration diagram of a vehicle antitheft device.

FIG. 4 is a block diagram in which a communication line of a failure diagnosis unit and a communication line of an immobilizer control unit of a vehicle antitheft device showing a conventional example are connected to an engine control unit.

[Explanation of symbols]

 2 Anti-theft device for vehicle 4 Ignition key 6 Coil unit 8 Immobilizer control unit (anti-theft control unit) 10 Engine control unit 14 Transponder 16 Coil unit 18 Coil circuit unit 22 Ignition circuit 24 Fuel injection valve 26 Ignition coil 28 Fault diagnosis unit 30 Failure Diagnosis Communication Line 32 Immobilizer Communication Line 34 Power Supply Line 36 Relay

Claims (2)

[Claims] 1. An ignition key provided with a transponder is provided, and a coil unit is provided for supplying an electric power to the transponder by inserting the ignition key and rotating it to a starting position to generate an identification code and output the identification code. , If an identification code input from this coil unit is positive, an immobilizer control unit that outputs an engine drive permission signal when the identification code is negative and outputs an engine drive inhibition signal when the identification code is negative is provided, and the ignition key is moved to the starting position. An engine control unit is provided to continue driving the engine when the engine drive permission signal is input from the immobilizer control unit within a set communication time from the start of rotation by the rotation of the engine control unit in the communication method. Use the master failure diagnosis unit as a communication line for failure diagnosis A vehicle theft, characterized in that the immobilizer control unit, which is connected to the engine control unit and serves as a master in a communication method with respect to the engine control unit, is connected to the failure diagnosis communication line through an immobilizer communication line. Prevention device. 2. The fault diagnosis unit is provided in the middle of a power supply line with a normally-closed relay that is opened during communication with the engine control unit by the immobilizer control unit. The anti-theft device for a vehicle according to claim 1.