JP3913823B2 - Vehicle start permission device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vehicle start permission device provided with a control means for permitting the start of an engine when an identification code read from an ID storage medium matches a preset one.
[0002]
[Problems to be solved by the invention]
Conventionally, vehicles having an immobilizer function have been provided to increase vehicle security. In this immobilizer function, when an immobilizer ECU is installed in a vehicle and an electronic key storing a unique identification code is inserted into an ignition switch, the immobilizer ECU reads the identification code from the electronic key, and the identification code is registered in advance. The engine is allowed to start only in accordance with the operation of the ignition switch using the electronic key only when it matches the identification code. Therefore, it is prohibited to start the engine with an electronic key in which no identification code is stored or registered, so that security can be improved.
[0003]
However, since the above-described immobilizer ECU operates based on a program stored in the ROM, the identification code verification method or the identification code registration method is fixed to the immobilizer ECU. For this reason, if the verification method of the identification code or the registration method of the identification code becomes known, there is a disadvantage that the identification code can be easily decoded and the security is lowered.
[0004]
In this case, it is possible to upgrade the program to improve the security, but since it is not assumed that the ROM will be replaced, the whole must be replaced, and the cost is high and the user is burdened. Become.
[0005]
The present invention has been made in view of the above circumstances, and an object thereof is to provide a vehicle start permission device that can easily cope with a program change.
[0006]
[Means for Solving the Problems]
The present invention relates to a non-volatile device that can be rewritten from the outside in a vehicle start permission device having a control means for permitting engine start when an identification code read from an ID storage medium matches a preset one. A storage means stage ; a program reading means for reading a program from a program storage medium; and a rewriting means for updating and storing the program read by the program reading means in the nonvolatile storage means . It operates based on the program stored in the storage means, the rewriting means temporarily stores the program read by the program reading means, and the identification code read from the ID storage medium is preset based on the program is a program temporarily stored when consistent with ones those to update stored in the nonvolatile memory means ( Motomeko 1).
[0007]
According to such a configuration, the control unit reads the identification code from the ID storage medium by operating based on the program stored in the nonvolatile storage unit. At this time, when it is determined that the identification code read from the ID storage medium matches that set in advance, the engine is allowed to start.
[0010]
When the program reading unit reads the program from the program storage medium in order to upgrade the program, the rewriting unit updates and stores the program read by the program reading unit in the nonvolatile storage unit. Thereby, the program stored in the program storage medium can be easily updated and stored in the nonvolatile storage means.
[0012]
Here, the rewriting means determines whether or not the identification code read from the ID storage medium matches the preset one based on the program read from the program storage medium and temporarily stored. At this time, if they do not match, the temporarily stored program is not updated and stored in the nonvolatile storage means, so even if an ID storage medium storing a new identification code is not available, Starting of the engine can be permitted based on the identification code stored in the ID storage medium up to.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 schematically shows the overall configuration. In FIG. 1, an immobilizer ECU 1 is installed in the vehicle. The immobilizer ECU 1 is mainly configured by a control circuit 2 (corresponding to the control means and the rewriting means of the present invention), and the control circuit 2 is for executing fixed control according to a program stored in the ROM 3. It comprises a first control unit 2a and a second control unit 2b for executing ID verification in accordance with an ID verification algorithm program stored in the flash memory 4. In this case, the program stored in the ROM 3 is a program that does not need to be changed regardless of the version upgrade of the program, and the program stored in the flash memory 4 is a program that is changed by the version upgrade.
[0014]
A power transmission and data signal transmission / reception circuit 5 is connected to the immobilizer ECU 1, and the immobilizer ECU 1 outputs a power signal and a data signal while the transmission / reception circuit 5 is driven.
[0015]
A coil 6 and a capacitor 7 are connected to the transmission / reception circuit 5, and a resonance circuit 8 is constituted by the coil 6 and the capacitor 7. In this case, the coil 6 is disposed so as to surround a tip portion of an ignition cylinder (not shown), and is opposed to the electronic key in a state in which the electronic key is inserted into the ignition cylinder.
[0016]
Here, the transmission / reception circuit 5 outputs a power signal of a predetermined frequency to the resonance circuit 8 by being driven by the immobilizer ECU 1 and superimposes the received data signal on the power signal when receiving the data signal from the immobilizer ECU 1. In the state, it outputs to the resonance circuit 8.
[0017]
A key remind switch 9 is connected to the immobilizer ECU 1. This key remind switch 9 is for detecting that an electronic key has been inserted into the ignition cylinder, and notifies the immobilizer ECU 1 that the insertion of the electronic key has been detected.
[0018]
When the key remind switch 9 detects the insertion of the electronic key into the ignition cylinder, the immobilizer ECU 1 reads the identification code from the electronic key as will be described later, and the read identification code matches that registered in advance. Gives an engine start permission signal to the engine ECU 10.
[0019]
The engine ECU 10 starts the engine when it receives a start signal from the ignition switch in a state where the engine start permission signal is given from the immobilizer ECU 1.
[0020]
Here, the immobilizer ECU 1 is provided so that a card reader 11 can be connected thereto. The card reader 11 is provided so that an IC card 12 storing an ID collation algorithm program can be inserted, and the ID collation algorithm program stored in the IC card 12 is read and transmitted to the control circuit 2 in the inserted state. ing.
When receiving the ID verification algorithm program from the card reader 11, the control circuit 2 updates and stores the program in the flash memory 4.
[0021]
Next, the electronic key will be described. The electronic key 13 is configured by incorporating a transponder 14 (corresponding to the ID storage means of the present invention) in a united state in a key grip, and transmits an identification code in a power supply state from the transmission / reception circuit 5. It is supposed to be.
[0022]
In other words, the transponder 14 is provided with a resonance circuit 17 including a coil 15 and a capacitor 16, and the coil 15 faces the coil 6 on the immobilizer ECU 1 side when the electronic key 13 is inserted into the ignition cylinder. It becomes a combined state. When a power signal is output from the coil 6 provided on the ignition cylinder side in this electromagnetic coupling state, the resonance circuit 17 receives the power signal and generates AC power, and the AC power is smoothed by the power circuit 18. Thus, power is supplied to the control circuit 19 in a state converted into DC power.
[0023]
The control circuit 19 operates in the power supply state, and transmits the identification code stored in the storage circuit 20 by operating based on the program stored in the storage circuit 20.
[0024]
The data signal receiving circuit 21 is for discriminating a data signal included in the power signal received by the resonance circuit 17, and gives the discriminated data signal to the control circuit 19. The impedance conversion circuit 22 outputs a data signal by converting the impedance of the resonance circuit 17 in accordance with a command from the control circuit 19.
[0025]
Next, the operation of the above configuration will be described.
When the electronic key 13 is inserted into the ignition cylinder to get on the vehicle and start the engine, the key remind switch 9 detects this and notifies the immobilizer ECU 1 of it.
[0026]
Then, since the immobilizer ECU 1 drives the transmission / reception circuit 5, a power signal is transmitted from the transmission / reception circuit 5. As a result, the coil 6 disposed at the tip of the ignition cylinder and the coil 15 of the transponder 14 are in an electromagnetically coupled state, and AC power is generated in the coil 15, so that the AC power is smoothed to DC power by the power supply circuit 18. Power is supplied to the control circuit 19 and the control circuit 19 is activated.
[0027]
And immobilizer ECU1 outputs a question signal with respect to the transmission / reception circuit 5 in the output state of the electric power signal mentioned above.
When the transmission / reception circuit 5 receives the interrogation signal from the immobilizer ECU 1, the transmission / reception circuit 5 outputs the interrogation signal superimposed on the power signal. Therefore, the data signal reception circuit 21 of the transponder 14 receives the interrogation signal superimposed on the power signal. Discriminated and output to the control circuit 19.
[0028]
When receiving the question signal, the control circuit 19 reads out the identification code (digital signal) stored in the storage circuit 20 and outputs it to the impedance conversion circuit 22. As a result, the power signal undergoes impedance conversion according to the digital signal indicating the identification code, so that the voltage level changes.
[0029]
At this time, since the coil 6 on the immobilizer ECU 1 side and the coil 15 of the transponder 14 are in an electromagnetically coupled state, when the voltage level of the power signal is changed by impedance conversion as described above, the transmission / reception circuit 5 has the voltage level of the power signal. An identification code is extracted based on the change and given to the immobilizer ECU 1.
[0030]
Thereby, immobilizer ECU1 judges whether the given identification code corresponds with what was registered beforehand, and when it corresponds, it gives an engine start permission signal to engine ECU10.
In this case, the determination of the identification code by the immobilizer ECU 1 described above is performed in a few ms, and the operation ends after the driver inserts the electronic key 13 into the ignition cylinder and rotates it.
[0031]
When the driver rotates the electronic key 13 to the start position, a start signal is given to the engine ECU 10 from the ignition switch, and the engine ECU 10 starts the engine by energizing the starter circuit.
With the above operation, when the electronic key 13 is authorized, the engine can be started by an operation on the ignition switch by the electronic key 13.
[0032]
By the way, in order to upgrade the ID verification function by the immobilizer ECU 1, it is necessary to replace the entire immobilizer ECU 1, but this increases the cost. In this embodiment, the immobilizer ECU 1 is replaced as follows. The ID verification function can now be upgraded.
[0033]
That is, FIG. 2 shows the operation of the second control unit 2b of the control circuit 2 of the immobilizer ECU 1 when changing the ID collation algorithm program. In FIG. 2, the second control unit 2b operates based on a program stored in the flash memory 4, and determines whether or not there is an algorithm rewriting operation (S1). This algorithm rewriting operation is usually performed by a car dealer, and an algorithm is used when a predetermined operation, which is a combination of opening / closing operation of the driver's seat door and rotation operation on the ignition switch, is performed within a predetermined time. It is determined that a rewrite operation is performed.
[0034]
Therefore, when a predetermined algorithm rewriting operation is performed, first, ID collation of the electronic key 13 is performed based on the algorithm program stored in the flash memory 4, and when it is the regular electronic key 13 (S2). : YES), the timer is started (S3). This timer is for setting a time limit required for inputting the ID verification algorithm program from the card reader 11.
[0035]
Now, when the IC card 12 storing the upgraded ID collation algorithm program is inserted into the card reader 11, the card reader 11 reads the ID collation algorithm program stored in the IC card 12 and performs the second control of the immobilizer ECU 1. To the unit 2b.
[0036]
Then, the second control unit 2b stores the ID verification algorithm program read by the card reader 11 in the temporary storage area of the flash memory 4 (S6), and starts a timer (S7). This timer is for setting a time limit required for registering the identification code of the electronic key 13 by the read ID collation algorithm program.
[0037]
Then, based on the new ID collation algorithm program read by the second control unit 2b as described above, it is determined whether the identification code of the electronic key 13 has been registered in advance (S8).
[0038]
At this time, when it is determined that the identification code of the electronic key 13 is registered in advance based on the new ID verification algorithm program (S8: YES), the new ID verification algorithm program stored in the flash memory 4 is replaced with the old algorithm. Update and store in the program storage area. Therefore, thereafter, the above-described ID verification of the electronic key 13 is executed based on the new ID verification algorithm program stored in the flash memory 4.
[0039]
If the timer has expired without registering the ID of the electronic key 13 (S9: YES), the new algorithm program stored in the flash memory 4 is discarded. Thus, even when the electronic key 13 storing the new identification code is not available when the ID verification algorithm program is upgraded, the engine can be started by using the electronic key 13 so far. Can do.
[0040]
According to such a configuration, the flash memory 4 is provided in the immobilizer ECU 1, and the ID verification algorithm program is stored in the flash memory 4, and the ID verification algorithm program stored in the flash memory 4 is written when the program is upgraded. Since the change is made, the program can be upgraded without replacing the immobilizer ECU 1. Therefore, compared with the configuration in which the immobilizer ECU 1 is replaced when the program is upgraded, the cost is not reduced and the user is not burdened.
[0041]
The present invention is not limited to the above embodiment, but can be modified or expanded as follows.
The program read by the card reader 11 may be directly updated and stored in the flash memory 4.
[0042]
A CD-ROM may be used as means for reading the ID verification algorithm program.
The entire upgraded program may be stored in the flash memory 4.
An EEPROM may be used instead of the flash memory 4.
[0043]
【The invention's effect】
As is apparent from the above description, the vehicle start permission device of the present invention has the following effects.
According to the first aspect, since the nonvolatile storage means storing the program for operating the control means can be rewritten from the outside, the version of the program can be easily upgraded.
[0044]
According to the second aspect of the present invention, since the program stored in the program storage medium is stored in the nonvolatile storage means, the program stored in the nonvolatile storage means can be easily updated.
[0045]
According to the third aspect, when the identification code read from the ID storage medium matches the preset identification code based on the program read from the program storage medium and temporarily stored, the temporarily stored program is stored in a non-volatile manner. Since the ID storage medium storing the new identification code is not available, even if the ID storage medium storing the new identification code is not available, the engine storage unit is updated based on the identification code stored in the previous ID storage medium. Start can be allowed.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing the overall configuration of an embodiment of the present invention. FIG. 2 is a flowchart showing the operation of an immobilizer ECU.
1 is an immobilizer ECU, 2 is a control circuit (control means, rewriting means), 4 is a flash memory (nonvolatile storage means), 14 is a transponder (ID storage medium), 10 is an engine ECU, 11 is a card reader (program reading) Means), 12 is an IC card (program storage medium), and 13 is an electronic key.

Claims (1)

When the identification code read from the ID storage medium coincides with the preset one, in the vehicle start permission device provided with the control means for permitting the engine start,
Non-volatile storage means rewritable from outside ;
Program reading means for reading a program from a program storage medium;
Rewriting means for updating and storing the program read by the program reading means in the nonvolatile storage means ,
The control means operates based on a program stored in the nonvolatile storage means ,
The rewriting means temporarily stores the program read by the program reading means, and stores the program temporarily stored when the identification code read from the ID storage medium matches a preset one based on the program. A start permission device for a vehicle, which is updated and stored in the characteristic storage means .

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