JPH07324533A - Security system - Google Patents

Abstract

PURPOSE:To reduce the number of part items by simplifying the structure of a key unit combined with both keyless entry and immobilizer functions. CONSTITUTION:A secret code transmitting part 2 transmitting a secret code signal as an electromagnetic wave by power feeding is installed in a key unit 4, and electric power is fed to this secret code transmitting part 2 from a power source 8 by the making of a control switch 7 at this key unit 4. Likewise the power is fed to the secret code transmitting part 2 through a magnetic coupling action between a transmitting coil 10 at the side of an ignition switch 5 and a receiving coil 9 at the side of the key unit 4. In addition, a receiver 6 receiving the secret code signal and having confirmed the congruity of a secret code is made to output a key signal driving a door lock mechanismic part in time of a case 1, but in time of a case 2, making it output a start allowing signal to an engine starting part 15. With this constitution, all parts are made into being commonable as to the secret code transmitting part 2, whereby structural simplification in the key unit and a reduction in the number of part items both are well promotable.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a security system having a keyless entry system function and an immobilizer system function.

[0002]

2. Description of the Related Art In recent years, a keyless entry system has been developed that locks or unlocks a key by transmitting and receiving electromagnetic waves.
For example, it is widely used for door locks of automobiles and houses. In such a keyless entry system, when the remote control key is operated and a predetermined signal is transmitted and output from the remote control key, the receiver receives the signal, and the key signal is output from the receiver to perform the keying or unlocking operation. The lock mechanism is configured to perform. More specifically, in general, the remote control key modulates a predetermined secret code and transmits and outputs it as an electromagnetic wave such as infrared rays and radio waves, and the receiver detects the received electromagnetic wave and takes out the secret code.
In this structure, it is determined whether or not the secret codes thus extracted are matched and the key signal is selectively output, and the door lock mechanism section is caused to perform a keying operation or a key releasing operation by the output of this key signal.

In recent years, an immobilizer system that permits the engine to start only when the identity of the keys is confirmed has been generally installed in automobiles and the like for security reasons. Such an immobilizer system, in general, an immobilizer that modulates a predetermined secret code to an ignition key and transmits and outputs it as an electromagnetic wave is embedded, and a receiver that receives the electromagnetic wave transmitted and output from this immobilizer is installed on the vehicle side. The receiver is configured to detect the received electromagnetic wave, take out the personal identification code, determine whether the personal identification code thus extracted coincides or not, and selectively output a start permission signal to the engine starting unit.

FIG. 4 shows an example of a conventional keyless entry system and immobilizer system. First, this system includes a key unit 4 having an ignition key 1, a secret code transmitting section 2 and an immobilizer 3, an ignition switch 5 into which the ignition key 1 is inserted in a key hole (not shown), the secret code transmitting section 2 and the secret code transmitting section 2. It comprises a receiver 6 for receiving a signal from the immobilizer 3.

The secret code transmitting section 2 has a structure in which a predetermined secret code stored in a memory (not shown) is modulated and transmitted as electromagnetic waves such as infrared rays and radio waves. In such a secret code transmitting section 2, a charging place 8 as a power source for supplying electric power to each section by turning on the operation switch 7,
The power receiving coil 9 connected to the charging place 8 is connected.

The immobilizer 3 has a structure in which a predetermined secret code stored in a memory (not shown) is modulated and transmitted and output as an electromagnetic wave.

The ignition switch 5 includes a power transmission coil 10 and a key detection switch 1 as a key detection means which is turned on when the ignition key 1 is inserted.
1 and an oscillation circuit 12 that energizes the power transmission coil 10 to generate a magnetic field when the key detection switch 11 is turned on.
It is composed of and. The power transmission coil 10 is connected to a transmitter / receiver (not shown) of the receiver through an antenna wire 13. The ignition switch 5 has an off position, an on position, and a start position, and has a structure for outputting to the receiver 6 a signal corresponding to the position where the inserted ignition key 1 is located. That is, when the ignition key 1 is in the off position, the key detection switch 11 is turned on to output an off signal, in the on position, an on signal is output, and in the start position, a start signal is output. It is configured to output. The ignition switch 5 has a built-in return spring (not shown) that returns the position from the start position to the on position.

The receiver 6 has a structure for receiving a personal identification code signal, detecting the personal identification code, extracting the personal identification code, determining whether or not the personal identification code thus extracted coincides, and outputting a key signal, a start permission signal, or the like. The receiver 6 includes an actuator 14 for driving a door lock mechanism (not shown) and an engine EC as an engine starter.
A U15 (ECU: Electronic Control Unit), a fuel pump 16, and a starter motor 17 are connected to each other.

The key unit 4 having such a structure is
Has a function as a remote control key in the keyless entry system and a function as an ignition key 1.
It functions as the immobilizer 3.

That is, when the operation switch 7 is turned on, power is supplied from the charging place to the secret code transmitting section 2, and the secret code transmitting section 2 transmits and outputs the secret code signal. Then, the personal identification code signal is received by the receiver 6 and it is determined whether the personal identification codes match. When it is determined that the secret codes match, a key signal is output from the receiver 6 and the actuator 14 is driven to lock or unlock the door. Here, the function as the keyless entry system is executed.

When the ignition key 1 is inserted into the ignition switch 5, the key detection switch 11 is turned on, the power transmission coil 10 is energized by the oscillation circuit 12, and a magnetic field is generated in the power transmission coil 10. This allows
The power transmission coil 10 and the power reception coil 9 are magnetically coupled, and the charging location 8 is charged by the magnetic coupling action at this time.

On the other hand, when a magnetic field is generated in the power transmitting coil 10 energized by the oscillator circuit 12, not only the power receiving coil 9 but also the power transmitting coil 10 and the immobilizer 3 are magnetically coupled, and the immobilizer 3 at this time is magnetically coupled.
The immobilizer 3 transmits and outputs the personal identification code signal as an electromagnetic wave. The secret code signal output in this way is received by the receiver 6 from the power transmission coil 10 through the antenna wire 13, and it is determined whether the secret codes match. When it is determined that the personal identification codes match, the receiver 6 outputs a start permission signal to the engine ECU 15. That is, the ignition key 1 is inserted into the ignition switch 5, and the engine start is permitted only when the secret codes of the ignition key 1 side and the receiver 6 side match. Here, the function as the immobilizer system is executed.

The key detection switch 11 determines whether the receiver 6 outputs the key signal or the start permission signal when the personal identification codes match. That is, when the key detection switch 11 is on, the start permission signal is output.

When the ignition key 1 is inserted into the ignition switch 5, the ignition switch 5 is off. When the ignition key 1 is rotated from this state, the ignition switch 5 is turned to the on position and the fuel pump 16 is driven through the receiver 6 on condition that a start permission signal is output to the engine ECU 15, and a fuel injection device (not shown) of the engine is driven. Gasoline is sent to. Then, when the ignition key 1 is further rotated, the ignition switch 5 is set to the start position, and the engine ECU
On condition that the start permission signal is output to 15, the starter motor is driven through the receiver 6 to start the engine.

[0015]

In the device having the function of the keyless entry system and the function of the immobilizer system like the device illustrated in FIG. 4, a structure for realizing the two functions in the key unit, that is, Figure 4
The device illustrated in FIG. 1 includes a personal identification code transmitter 2 and an immobilizer 3. However, since these structures are configured separately and independently, there is a drawback that the key unit becomes large. Further, in the device shown in FIG. 4 in which the same secret code is used for the keyless entry system and the immobilizer system, circuits having the same function must be separately prepared for each system, which is uneconomical. There is a problem that it becomes a structure.

[0016]

SUMMARY OF THE INVENTION According to the present invention, a key hole into which an ignition key is inserted, a power transmission coil arranged around the key hole, and a key detection for detecting that the ignition key is inserted into the key hole. Means, an ignition switch having an oscillation circuit that energizes a power transmission coil to generate a magnetic field when the key detection means detects an ignition key, an ignition key inserted into a key hole, a portable power supply, and power supply. By doing so, a PIN code signal including a specified PIN code is transmitted and output as an electromagnetic wave, an operation switch for supplying power from the power supply to the PIN code transmitter by turning on the operation code, and a front front ignition key is inserted into the key hole. In this state, it is magnetically coupled to the power transmission coil and this magnetic coupling action feeds the secret code transmitter. A key unit having a power-receiving coil and a personal identification code signal are received, and whether the personal identification code coincides or not is discriminated based on the received personal identification code signal. When the personal identification code coincides, the detection result of the key detection means is determined. And a receiver for selectively outputting a key signal to the door lock mechanism section or a start permission signal to the engine starting section.

[0017]

[Action]

[Keyless Entry System] When the operation switch is turned on, power is supplied from the power source to the secret code transmitting section, and the secret code signal is transmitted and output as an electromagnetic wave from the secret code transmitting section. Then, the receiver that receives the secret code signal and confirms the coincidence of the secret code outputs a key signal to the door lock mechanism section. As a result, the function of the keyless entry system is executed.

[Immobilizer system] When the key detection means detects that the ignition key is inserted in the key hole of the ignition switch, the oscillation circuit energizes the power transmission coil to generate a magnetic field in the power transmission coil. Then, the power transmitting coil and the power receiving coil on the side of the key unit are magnetically coupled to each other, and power is supplied to the personal identification code transmitting unit, and the personal identification code signal is transmitted and output as an electromagnetic wave from the personal identification code transmitting unit. At this time, since the key detection means detects that the ignition key is inserted in the key hole of the ignition switch, the receiver that receives the secret code signal and confirms that the secret code matches the engine starting part. To output a start permission signal. As a result, the function of the immobilizer system is executed.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described with reference to FIGS. The same parts as those described with reference to FIG. 4 are designated by the same reference numerals, and the description thereof will be omitted. First, in the key unit 4 of the present embodiment, as shown in a block diagram in FIG. 1, a CPU 21 that executes various kinds of arithmetic processing to centrally control each unit, and a memory 22 connected to this CPU 21.
And the transmission / reception unit 23 that transmits and receives electromagnetic waves constitute the secret code transmission unit 2. The memory 22 stores fixed data such as operation programs and has a work area. Further, the memory 22 has a personal identification code area 22a in which the personal identification code is rewritably stored.
And a cryptographic function area 22b for rewritably storing the cryptographic function. Further, the power receiving coil 9 is connected to the CPU 21, and the power receiving coil 9 is connected in parallel with a capacitor C and an electric field 8 with an operating switch 7 interposed therebetween.

In the key unit 4 of this embodiment, the immobilizer 3 is not provided, and the immobilizer function is executed by the secret code transmitting section 2 and the like.

Next, the receiver 6 executes various arithmetic processes to centrally control each unit, a memory 25 connected to the CPU 24, and the CPU 2
4, a transmission / reception section 26 for transmitting and receiving electromagnetic waves, an SCI 27 serving as an interface between the CPU 24 and the engine ECU 15, the CPU 15, the actuator 14, the fuel pump 16, and the starter motor 1.
7 and the interface 28. The memory 25 is provided with a personal identification code area 25a for rewritably storing a personal identification code and a cryptographic function area 25b for rewritably storing a cryptographic function. It should be noted that each unit such as the CPU 24 in the receiver 2 is configured to be intermittently supplied with electric power from a battery of an automobile (not shown).

In such a structure, the key unit 4
The processing flow on the side of the receiver 6 will be described based on the flowchart shown in FIG. 2, and the processing flow on the side of the receiver 6 will be described based on the flowchart shown in FIG.

[Processing as Keyless Entry System] First, in FIG. 2, when the operation switch 7 of the key unit 4 is turned on, power is supplied to each part from the power source 8 in step S1. In the following step S2, the personal identification code stored in the personal identification code area 22a of the memory 22 is converted into a personal identification code signal, which is transmitted and output as a start signal which is an electromagnetic wave from the transmitting / receiving unit 23.

When such a start signal is received by the transmitter / receiver 26 of the receiver 6, step S11 in FIG.
Random number generation processing is performed. That is, a predetermined random number is created by the arithmetic processing of the CPU 24 and the like. In the subsequent step S12, the random number signal is transmitted and output as an electromagnetic wave from the transmitting / receiving unit 26.

As shown in FIG. 2, in the key unit 4,
In step S3, the reception of the random number signal is waited until the time up in step S4. If the random number signal is received by the transceiver unit 23 of the key unit 4 before the time is up, step S
After the secret code generation process in 5 and the transmission output process of the secret code signal by the transmitting / receiving unit 23 in step S6, the power supply stop process is executed in step S7, and the process is ended.
On the other hand, when the time is up in step S4 without receiving the random number signal in step S3, the process proceeds to the power supply stop process in step S7, and the process ends. Here, the creation of the personal identification code in step S5 is performed by, for example, the memory 22.
This is done by substituting the secret code and the received random number stored in the secret code area 22a into the cryptographic function formula stored in the cryptographic function area 22b. For example, if the personal identification code consists of four digits abcd, cryptographic function F serving as security code (x) is defined as ^{F (x) = ax 3 +} bx 2 + cx + d ......... 1 expression, etc., personal identification to abcd The corresponding digit of the code is substituted and a random number is substituted for x to obtain F (x).

In the receiver 6 which has completed the random number generation process in step S11, the secret code generation process is performed in step S13 as shown in FIG. The secret code creating process here is the same as the secret code creating process in step S5 of the key unit 4. That is, the cryptographic function area 25b of the memory 25 stores the same cryptographic function equation as the cryptographic function equation stored in the cryptographic function area 22b of the key unit 4, and the same numerical value is substituted into this cryptographic function equation. A secret code is created by. Continued Step S14
Then, waiting for reception of the personal identification code signal transmitted and output from the key unit 4, that is, the signal including the personal identification code created in step S5, there is a discrepancy between the personal identification code created by itself and the received personal identification code in step S15. To be judged. If it is determined in step S15 that the personal identification codes do not match, the process ends, and if it is confirmed that the personal identification codes match, the process proceeds to step S16 and the key detection switch 11
Can be seen. That is, the ignition switch 5
It is determined whether or not the ignition key 1 is inserted. Here, since it is used as a keyless entry system, it is determined that the key detection switch 11 is off. Then, in step S17, a key signal, that is, a signal for driving the actuator 14, is output to the actuator 14, and a door lock mechanism unit (not shown) is driven to perform a keying operation or a key releasing operation of the door.

In this way, the processing as the keyless entry system is executed.

[Processing as Immobilizer System]
On the other hand, when the ignition key 1 is inserted into the key hole of the ignition switch 5, the key detection switch 11 is turned on, the power transmission coil 10 is energized by the transmission circuit 12, and a magnetic field is generated in the power transmission coil 10. Then, the power transmitting coil 10 and the power receiving coil 9 on the side of the key unit 4 are magnetically coupled with each other so that electric charges are stored in the capacitor C, and the secret code transmitting section 2 is supplied with power by such magnetic coupling action and storage action. That is, the process of step S1 in FIG. 2 is executed. As a result, the process up to step S7 following step S1 is performed on the key unit 4 side, and accordingly, the process following step S11 shown in FIG. 3 is performed on the receiver 6 side. At this time, electromagnetic waves are transmitted and received between the transmitter / receiver 23 on the key unit 4 side and the transmitter / receiver 26 on the receiver 6 side through the power transmission coil 10 and the antenna wire 13 on the ignition switch 5 side.

When the ignition key 1 is inserted in the key hole of the ignition switch 5, the receiver 6 determines in step S16 that the key detection switch 11 is on. Therefore, the process proceeds to step S18, and in this step S18, the output process of the start permission signal to the engine ECU 15 is executed. The output processing of the start permission signal here is preferably a rolling code processing between the SCI 27 of the receiver 6 and the engine ECU 15. Normally, the receiver 6 side and the engine EC
This is because the cord is generally connected to the U15 side, so that the code may be broken and the personal identification code may be grasped, so that such a criminal act is surely prevented.

In this way, the processing as the immobilizer system is executed.

As described above, in this embodiment, one secret code transmitting section 2 provided in the key unit 4 has the secret code transmitting function required for the keyless entry function and the secret code transmitting function required for the immobilizer function. Therefore, the structure of the key unit 4 can be simplified and the number of parts can be reduced.

[0032]

According to the present invention, the personal identification code transmitting section for transmitting and outputting the personal identification code signal as an electromagnetic wave by being supplied with electricity is provided in the key unit, and when the operation switch is turned on, the personal identification code transmitting section is supplied with power to supply the personal identification code transmitting section. A signal is transmitted and output, in this case, a receiver that receives the secret code signal outputs a key signal for driving the door lock mechanism section,
Also, with the ignition key inserted in the ignition switch, the power supply coil on the ignition switch side and the power receiving coil on the key unit side are magnetically coupled to each other to supply power to the personal identification code transmitter to transmit and output the personal identification code signal. In this case, the receiver that received the PIN code signal was configured to output a start permission signal to the engine starter, so the PIN code transmission function required for the keyless entry function and the PIN code transmission function required for the immobilizer function Can serve also as one secret code transmitting section provided in the key unit, and therefore, the key unit can be simplified in structure and the number of parts can be reduced.

[Brief description of drawings]

FIG. 1 is a block diagram of an entire system showing an embodiment of the present invention.

FIG. 2 is a flowchart showing the flow of processing on the key unit side.

FIG. 3 is a flowchart showing a processing flow of a receiver that has received a start signal.

FIG. 4 is a block diagram of an entire system showing a conventional example.

[Explanation of symbols]

 1 Ignition key 2 PIN code transmitter 4 Key unit 5 Ignition switch 6 Receiver 7 Operation switch 8 Power supply 9 Power receiving coil 10 Power transmission coil 11 Key detection means 12 Oscillation circuit

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Noboru Nishimoto 6-11-11 Shimbashi, Minato-ku, Tokyo Yushin Co., Ltd. 2nd Design Department

Claims (1)

[Claims] 1. A key hole into which an ignition key is inserted, a power transmission coil arranged around the key hole, a key detecting means for detecting that the ignition key is inserted into the key hole, and this key detection. An ignition switch having an oscillation circuit that energizes the power transmission coil to generate a magnetic field when the means detects the ignition key, and the ignition key inserted into the key hole,
A power supply having portability, a personal identification code transmitting section that transmits and outputs a personal identification code signal including a predetermined personal identification code as an electromagnetic wave by being supplied with power, and an operation switch that causes the personal identification code transmitting section to be supplied with power from the power source by an insertion operation. ,
A key unit having a power receiving coil that is magnetically coupled to the power transmitting coil in a state where the front ignition key is inserted in the key hole and supplies power to the secret code transmitting unit by this magnetic coupling action, and a secret code signal is received. , It is determined whether or not the personal identification code matches based on the received personal identification code signal, and when the personal identification code is determined to be coincident, the key signal to the door lock mechanism section or the start permission to the engine starting section is permitted according to the detection result of the key detection means. A receiver that selectively outputs signals,
A security system including: