JP4841950B2 - Security system using electronic keys - Google Patents

Description

  The present invention relates to a security system using an electronic key that enables operation of a controlled member on condition that an ID code registered in the electronic key matches an ID code registered in advance.

  In recent years, a security system using an electronic key in which a transmission circuit is integrated with a mechanical key (key) has been used in order to improve vehicle theft prevention and house security. In such a security system using an electronic key, the key code transmitted from the electronic key is collated with the key code stored in the electronic control device, and only when it is determined to be a legitimate electronic key. In addition, an immobilizer system that permits the start of an engine in a vehicle and a keyless entry system that allows a door lock to be unlocked are known.

  In such a security system using an electronic key, the key code transmitted from the electronic key is read by a third party to prevent the electronic key from being copied, so that the key code is encrypted and transmitted. It is configured.

  As a security system using the above-described electronic key, there is a vehicle immobilizer system as described in Patent Document 1 below. In this vehicular immobilizer system, first, when the ignition switch is rotated to the ACC position by an electronic key, a random number code is transmitted from the start permission ECU on the vehicle side. The electronic key has a predetermined key code for each electronic key stored in advance based on the received random number code and a common vehicle code set for each vehicle stored in advance in the nonvolatile memory. A return code is created by performing cryptographic processing, and the return code is transmitted. The start permission ECU on the vehicle side that has received the return code reads the vehicle code from the nonvolatile memory, and decodes the key code and the random number code from the return code based on the vehicle code. The decrypted key code and the random number code are compared with each other and the key code stored in advance is compared with the random number code.

WO96 / 015346

  However, in the prior art described in Patent Document 1, the start permission ECU on the vehicle side matches the individual unique key code that is different for each electronic key and the key code stored in advance in the nonvolatile memory. In order to set a plurality of electronic keys for one vehicle, a key code corresponding to the number of electronic keys must be stored in the nonvolatile memory of the start permission ECU. However, since the storage area of the nonvolatile memory is limited, the number of key codes of electronic keys that can be registered in advance is limited.

  Therefore, if you own and manage multiple vehicles like a vehicle rental company, you can use a single electronic key to lock / unlock multiple vehicles and start an engine, so-called master key It is common that the key code of the electronic key called is registered in common with a plurality of vehicles.

  In particular, for example, vehicle construction machines such as backhoes often have a vehicle rental company that owns a plurality of vehicles and rents a plurality of vehicles collectively to a specific manufacturer. For this reason, when the rental vehicle breaks down or is regularly inspected, the vehicle rental company must know the location of the electronic key corresponding to the key code registered in each vehicle. If a specific electronic key cannot be found because there is no person who owns the registered electronic key even if a service person is dispatched to the rental destination, the engine start operation of the vehicle corresponding to the electronic key can be performed. Can not do it. For this reason, advance preparations such as confirming the location of the electronic key corresponding to each vehicle in advance are required, which complicates work and delays the response.

  Therefore, there is a demand for an immobilizer system that can set a plurality of electronic keys that enable engine start operations of a plurality of vehicles. If it is possible to set multiple electronic keys that can start the engine of such multiple vehicles, the vehicle rental company also has the same electronic key as the rental destination, so that The vehicle can be started with a single electronic key. Therefore, if the rental vehicle breaks down, the vehicle rental company does not need to confirm the location of the rental electronic key, so it can be dispatched with a serviceman holding the electronic key owned by the company. It can be done quickly and is very convenient.

  As described above, when the engine of a plurality of vehicles can be started with one electronic key and a plurality of electronic keys common to a plurality of vehicles are set for one vehicle, the above-mentioned patent is used. In the anti-theft device that assumes anti-theft for a specific vehicle as described in Document 1, the number of electronic keys that can be registered in one vehicle is limited, and thus cannot be adopted as it is. .

Therefore, in order to solve the technical problem, the present invention compares the code signal transmitted from the electronic key with the received code signal and the stored code signal. In a security system using an electronic key having a control unit that is permitted to operate, a code signal includes an ID code composed of different numbers for each electronic key and an identification code for identifying the function of the electronic key As an individual code stored as a group code, a group code set for each predetermined group, and a cryptographic code calculated by applying a predetermined cryptographic process based on the group code to an ID code composed of different numbers for each electronic key. the de provided a group key stored as the code signal together with the identification code identifying the function of the ID code and the electronic key, the control unit, Storage means for storing various code signals, and when receiving an ID code corresponding to the identification code of the individual key as the first code signal, the received ID code and the ID code of the individual key stored in the storage means When the ID code corresponding to the identification code of the group key is received as the first code signal, the permission signal for permitting the operation of the controlled member is output when the two match. The ID code is subjected to predetermined encryption processing based on the group code stored in the storage means to calculate the encryption code, and the calculated encryption code and the encryption code of the group key received as the second code signal comparing the example Bei comparison means for outputting a permission signal for operation permission of the controlled member when there is a match, the control unit The憶means, ID code of the group key is characterized in that no storage.

In particular, an immobilizer control unit that compares the code signal transmitted from the electronic key with the received code signal and the stored code signal and permits the engine start of the vehicle when they match is provided. In a security system using an electronic key,
An individual key storing an ID code composed of different numbers for each electronic key, an identification code for identifying the function of the electronic key as a code signal, a group code set for each predetermined group, and a group code storing predetermined encryption processing the encryption code which is calculated by applying the ID code configured individually different number for each electronic key, as a code signal together with the identification code identifying the function of the ID code and the electronic key based on A storage unit for storing the various code signals in the immobilizer control unit;
When the ID code corresponding to the identification code of the individual key is received as the first code signal, the received ID code is compared with the ID code of the individual key stored in the storage means. When an ID signal corresponding to the identification code of the group key is received as the first code signal while outputting a permission signal for permitting engine start of the vehicle, the group code stored in the storage means in the received ID code The encryption code is calculated by performing a predetermined encryption process based on the above, and the calculated encryption code is compared with the encryption code of the group key received as the second code signal. Bei give a comparison means for outputting a permission signal for,
The storage means of the control unit does not store the ID code of the group key .

  In the security system using the electronic key described above, the storage means is provided with a first storage area for storing the ID code of the individual key and a second storage area for storing the group code of the group key. The means is characterized in that any one of the storage areas is selected according to the identification code and the code signal is read.

  Further, in the security system using the electronic key described above, an ID code composed of individual different numbers for each electronic key, and an identification code indicating a registration function that permits rewriting or writing of various code signals to the storage means As a code signal, a group code set for each predetermined group, an encryption code calculated by applying a predetermined encryption process to the ID code based on the group code, and various code signals A group registration key storing an identification code indicating a registration function permitting rewriting or writing to the storage means as a code signal together with an ID code, and the comparison means uses an identification code of the registration key as a first code signal When the ID code corresponding to is received, the ID of the registration key stored in the storage means When the ID code corresponding to the identification code of the group registration key is received as the first code signal, the code means permits rewriting or writing of the various code signals to the storage means when they match. The received ID code is subjected to predetermined encryption processing based on the group code stored in the storage means to calculate the encryption code, and the group registration key received as the calculated encryption code and the second code signal The encryption code is compared with each other, and when they match, rewriting or writing of various code signals to the storage means is permitted.

  According to the present invention, it is not necessary to register the ID code of each group key in the storage means of the control unit or the immobilizer control unit, and it is only necessary to register one group code common to a plurality of group keys. Therefore, regardless of the storage area of the storage means, it is possible to set a plurality of group keys that can permit the operation of the controlled member or the engine start to the storage means of one control section or immobilizer control section.

  In addition, after transmitting the ID code, the group key transmits the encryption code separately, and the control unit or immobilizer control unit side performs a predetermined encryption process based on the received ID code and the group code stored in advance. The encryption code is calculated and compared with the received encryption code. Therefore, since the ID code is different even for a plurality of common group keys having the same group code, even if a third party illegally copies the encryption code of the group key, it is illegal unless the ID code is copied together with the encryption code. It is not possible to start the engine.

  Furthermore, since the group code of the group key is transmitted from the group key only when registering in the control unit or immobilizer control unit, and not transmitted when the engine is started, the encryption code is prevented by preventing unauthorized copying of the group code during use. Thus, it is possible to reliably prevent the ID code from being decoded.

  On the other hand, when copying a group key on the manufacturer side, if the group code and the encryption code are registered in the electronic key, the group key can be copied, so that the required number of group keys can be easily set. .

  As for a registration key having a registration function for permitting rewriting or writing of various code signals to the storage means, if the group code is registered in the storage means in association with the identification code of the group registration key, the storage means Regardless of the storage area, a plurality of group registration keys that can permit rewriting or writing of various code signals to the storage means can be set for the storage means of one control unit or immobilizer control unit.

Hereinafter, an embodiment in which a security system using an electronic key of the present invention is adopted as an immobilizer system for preventing vehicle theft will be described in detail with reference to the accompanying drawings.
FIG. 1 is a system block diagram of a vehicle antitheft immobilizer system according to the present invention, FIG. 2 is an explanatory diagram showing registration states of various code signals in the EEPROM of each electronic key, and FIG. 3 is a vehicle EEPROM. FIG. 4 is an explanatory diagram showing an electronic key that can be registered for a specific vehicle, and FIG. 5 is an electronic key that can be registered for a plurality of vehicle groups. It is explanatory drawing which shows.

  With reference to FIG. 1, the structure of the antitheft device for vehicles of Example 1 which concerns on this invention is demonstrated. As shown in FIG. 1, the vehicle antitheft device used in the first embodiment is captured by a transponder 60, a transceiver 20 having a coil antenna 21 that receives a signal from the transponder 60, and the coil antenna 21. The system includes an immobilizer ECU 10 (control unit, immobilizer control unit) to which a signal amplified by an amplifier that is not input is input, and an engine starter 30 that controls engine start by a signal from the immobilizer ECU 10.

  The transponder 60 is built in the key head 51 of the electronic key 50 owned by the driver who turns on / off the ignition switch 22 of the automobile, and stores various code signals to be described later as shown in FIG. An EEPROM 61, a transmission / reception circuit 62 including a coil antenna (not shown), a power circuit 63 that generates power from electromagnetic waves received by the coil antenna, and a CPU 64 that controls transmission / reception of a code signal. Further, the electronic key 50 in the first embodiment is provided with a key blade 52 in which a key code (key pile) unique to each electronic key 50 is formed.

  The steering lock body 25 is provided with a key cylinder 23 formed with a key insertion hole 24 into which the key blade 52 of the electronic key 50 can be inserted, and is connected to a rear end portion of the key cylinder 23. Thus, the ignition switch 22 is integrally incorporated. Further, a coil antenna 21 is disposed on the outer peripheral surface on the front end side of the steering lock body 25.

  The coil antenna 21 is connected to the transmitter / receiver 20, and operates when power is supplied to the transmitter / receiver 20 from a power supply circuit 13 (described later) in conjunction with the ON / OFF of the ignition switch 22. The ignition switch 22 is not shown by inserting the key blade 52 of the electronic key 50 into the key insertion hole 24 and rotating the key cylinder 23 from the key insertion position to the on position and then to the start position. The contact portion is configured to be switchable.

  In addition, the immobilizer ECU 10 responds to a request from the CPU 11 (comparison means) that performs control according to the code signal received by the coil antenna 21, an EEPROM 12 (storage means) that can register various code signals by rewriting or writing, and the CPU 11. Accordingly, the RAM is configured to temporarily store various code signals and the power supply circuit 13 connected to the battery 15. Therefore, when the electronic key 50 is inserted into the key cylinder 23 and the ignition switch 22 is turned from the off position to the on position, power is supplied from the battery 15 to the CPU 11 via the power supply circuit 13. Then, the CPU 11 activates the transceiver 20, and the transceiver 20 transmits an activation signal from the coil antenna 21 to the electronic key 50 as an electromagnetic wave. Further, when the ignition switch 22 is turned from the on position to the start position, a starter (not shown) is connected to the battery 15, and an engine start permission signal is output from the immobilizer ECU 10 to the engine start device 30. The engine 40 (controlled part) is started.

  On the other hand, in the transponder 60, when a coil antenna (not shown) constituting the transmission / reception circuit 62 receives the activation signal and electromagnetically couples with the coil antenna 21 of the transceiver 20, the power circuit 63 generates power and supplies it to the CPU 64. . The CPU 64 reads a code signal registered in advance in the EEPROM 61 and transmits it from the transmission / reception circuit 62 to the immobilizer ECU 10.

As shown in FIG. 2, in the EEPROM 61 of the electronic key 50, the ID code (1ax, 1bx, 1cx) set for each electronic key 50 and the electronic key 50 are specified to identify the electronic key 50. An identification code (K, T, M ) for identifying the function is registered in all the individual electronic keys 50 as basic information.

  Further, the specific electronic key 50 includes a group code (Y, W) common to the electronic keys 50 belonging to the same vehicle group (group), and a group code (Y) in the ID code (1ax, 1bx, 1cx) described above. , W), encryption codes (X1, X2) that have been subjected to encryption calculation processing are registered.

This identification code (K, T, M ) is an identification code “K” if the electronic key 50 is a normal key 55 that can permit engine start for a specific vehicle. If the registration key 56 permits the rewriting or writing of the ID code (1ax, 1bx, 1cx) or the group code (Y, W) to the EEPROM 12 of the immobilizer ECU 10 for a specific vehicle, the identification code “T”, In the case of the group key 57 that can permit the engine start to a plurality of vehicles in the same vehicle group, the identification code “ M ” is registered, and what function is determined by the identification code (K, T, M ). Can be identified. It should be noted that the normal key 55 and the registration key 56 are used as individual keys for the group key 57 because they are valid for one specific vehicle.

  On the other hand, as shown in FIG. 3, the EEPROM 12 of the immobilizer ECU 10 has three ID codes (1ax, 2ax, 3ax) of the normal key 55 and an ID code (1bx) of the registration key 56 as an identification code (K, T). It is registered to correspond to. Further, the ID code (1cx) of the group key 57 is not registered, and is registered so that the group code (Y) corresponds to the identification code (M).

  In the first embodiment, the storage area in which these three ID codes (1ax, 2ax, 3ax) can be registered is the first storage area 12A, and one group code (Y) can be registered. The storage area that can be registered with the ID code (1bx) of the registration key 56 is the third storage area 12C.

As shown in FIG. 4, the normal key 55 is an electronic key 50 that can start the engine of a specific vehicle (either car A or car B). The three normal keys 55A1, 55A2 and 55A3 can be set. Therefore, the normal key 55A1, 55A2, 55A3 corresponding to the car A cannot start the engine of the car B, and the normal key 55B1, 55B2, 55B3 corresponding to the car B cannot start the engine of the car A. .
In these normal keys 55, the ID code (1ax-6ax) and the identification code (K) are registered in advance in the EEPROM 61 of the transponder 50, and no group code is registered.

  On the other hand, the registration key 56 is a dedicated electronic key 50 that can register the above-described normal key 55 or a group key 57 (described later) in a corresponding specific vehicle (either car A or car B). It cannot be started. Therefore, the registration key (56A) corresponding to the car A cannot be used to register the electronic key 50 to the car B other than the car A, and the registration key (56B) corresponding to the car B is not a car other than the car B. The registration operation of the electronic key 50 for the A car cannot be performed.

  As shown in FIG. 2, the ID code (1bx, 2bx) and the identification code (T) are registered in advance in the EEPROM 61 of the transponder 60 of the registration key 56 as in the normal key 55, and the group code is registered. It has not been. The registration key 56 corresponds to a specific vehicle one by one and is basically registered in the EEPROM 12 of the immobilizer ECU 10 in the production line, so that the ID codes (1bx, 2bx) registered in the EEPROM 12 are rewritten. Therefore, only the ID code (1bx, 2bx) may be registered in the EEPROM 61 of the transponder 60 without registering the identification code (T).

  As shown in FIG. 5, the group key 57 is an electronic key 50 that can start the engine of a plurality of vehicles (A car, B car, and C car). It is possible to do. As shown in FIG. 2, in the group key 57, together with the ID code (1cx to 6cx) and the identification code (M), a group code (Y that is commonly registered in a plurality of vehicle groups constituting a predetermined group) ) And encryption codes (X1 to X6) are registered in the EEPROM 61 of the transponder 60 in advance. Since the encryption codes (X1 to X6) are obtained by performing encryption calculation processing on the ID code (1cx to 6cx) based on the group code (Y), a plurality of vehicles constituting the same group. Even the group key (57Y) set for the group (Y) has a different encryption code (X1, X2, X3... X6) for each group key (57Y).

  Further, the group key (57Y) of a plurality of vehicle groups (Y) constituting the same group cannot start the engines of the vehicles belonging to the plurality of vehicle groups (W) constituting the same group. The group key (57W) of the vehicle group (W) cannot start the engines belonging to the vehicle group (Y).

  The various codes described above are single-digit or multi-digit numerical values, and may be serial numbers or irregular numbers. In the figure, the same reference numerals indicate the same code, and the different reference numerals indicate different codes.

Next, the determination procedure on the immobilizer ECU 10 side in the first embodiment will be described with reference to the flowcharts shown in FIGS.
FIG. 6 is a flowchart showing a control operation on the immobilizer ECU side that shifts to each operation mode, FIG. 7 is a flowchart showing an engine start control operation by a normal key on the immobilizer ECU side, and FIG. 8 is a group key on the immobilizer ECU side. FIG. 9 is a flowchart showing a control operation for shifting to a registration mode by a registration key on the immobilizer ECU side, and FIG. 10 is a control operation for registering an ID code of a normal key on the immobilizer ECU side. FIG. 11 is a flowchart showing a control operation for registering a group key group code on the immobilizer ECU side.

  First, as shown in the flowchart of FIG. 6, when the ignition switch 22 is rotated to the ON position by the electronic key 50 built in the transponder 60, the process is started, and the immobilizer ECU 10 is connected to the CPU 11 from the battery 15 via the power supply circuit 13. The CPU 11 activates the transmitter / receiver 20 and transmits the activation signal (wake-up signal) from the coil antenna 21 as an electromagnetic wave. (Step S1 to Step S2)

  On the other hand, on the electronic key 50 side, when a wake-up signal is received by a coil antenna (not shown) of the transmission / reception circuit 62 built in the transponder 60, the power circuit 63 generates power and supplies it to the CPU 64. The CPU 64 transmits an ID code and an identification code registered in the EEPROM 61 as a first code signal from a coil antenna (not shown) of the transmission / reception circuit 62 to the coil antenna 21.

When the transmitter / receiver 20 receives the ID code and the identification code as the first code signal in step S3, it is inserted into the key cylinder 23 by comparing the identification code registered in the EEPROM 12 with the received identification code in step S4. The type of the electronic key 50 is identified. When the identification code is “K”, it is judged as a normal key 55, when the identification code is “T”, it is judged as a registration key 56, and when the identification code is “ M ”, it is judged as a group key 57. To do. (Step S5 to Step S9)

  When it is determined that the electronic key 50 is the normal key 55, the CPU 11 compares the ID code registered in the first storage area 12A of the EEPROM 12 with the received ID code. The operation mode is shifted to the normal key operation mode. (Step S5)

  Similarly, when it is determined that the key is the registration key 56, the CPU 11 compares the ID code registered in the third storage area 12C of the EEPROM 12 with the received ID code. When the operation mode of the registration key shown in FIG. (Step S8)

  The operation mode (engine start mode) of the normal key that shifts from step S6 will be described based on the flowchart of FIG. In the operation mode of the normal key 55, since it is determined in step S5 in FIG. 6 that the received ID code matches the ID code registered in the EEPROM 12, the ignition switch 22 is rotated to the start position in step S10. Then, in step S <b> 11, the CPU 11 outputs an engine start permission signal to the engine starter 30, and the engine starter 30 starts the engine 40.

  The engine starter 30 is generally an engine ECU that controls engine start in accordance with an engine start permission signal output from the CPU 11, but may be a simple starter relay. In this case, the CPU 11 is configured to start the engine 40 by supplying power to the starter relay when the ID code matches and turning on the relay.

  Next, the operation mode (engine start mode) of the group key 57 that shifts from step S7 will be described based on the flowchart of FIG. In the operation mode of the group key 57, in step S20, the CPU 11 activates the transmitter / receiver 20 and transmits an encryption code request signal from the coil antenna 21 to the transponder 60 as an electromagnetic wave. When the transmitter / receiver 20 receives the encryption code transmitted from the transponder 60, the ID code received based on the group code registered in the EEPROM 12 is subjected to encryption calculation processing in step S3 to calculate the encryption code. (Steps S21 to S22)

In step S23, the encryption code received by the transmitter / receiver 20 is compared with the encryption code calculated by the CPU 11, and only when the encryption codes match, the ignition switch 22 is turned to the start position to thereby rotate the CPU 11 Is output to the engine starting device 30, and the engine starting device 30 starts the engine 40. (Step S24 to Step S26)
The encryption code registered in the group key 57 is encrypted by performing the same encryption calculation process as the encryption calculation process performed by the CPU 11 in step S22.

  FIG. 9 is a flowchart showing the processing procedure of the operation mode (electronic key registration mode) of the registration key 56. In the state where the ignition switch 22 is rotated to the on position in step S1 in FIG. 6, the horn sounds and the driver is informed that the registration mode has been entered by holding the registration key 56 in the on position for 2 seconds. . (Step S30 to Step S32)

  If the registration key 56 remains in the ON position for a predetermined time or longer (15 seconds or longer in the present embodiment) despite the horn sounding, the registration key 56 is turned OFF after that. Even if the position is rotated and pulled out, the registration mode is not entered, and the registration mode is terminated as it is. (Step S33 to Step S34)

  On the other hand, after the horn sounds, the ignition switch 22 is turned to the OFF position, and the registration key 56 is removed from the key cylinder 23 within a predetermined time (within 10 seconds in this embodiment), and then the key cylinder 23 It is determined whether or not the ignition switch 22 has been turned to the ON position by the electronic key 50 inserted into the. (Steps S35 to S36) Then, when the electronic key 50 is held in the ON position for 2 seconds as it is, the horn sounds and the registration process is started. (Step S37 to Step S39)

  After the registration key 56 is pulled out in step S30, if the electronic key 50 to be registered is not inserted and the ignition switch 22 is not turned on within a predetermined time (within 10 seconds in this embodiment) (step S35) or in the ON position. If the ignition switch 22 is rotated to the OFF position even if the rotation operation is not performed for 2 seconds (step S40), the registration operation is finished as it is.

  As a registration process, a wake-up signal is transmitted from the coil antenna 21 to the transponder 60 as an electromagnetic wave in step S41. When the coil antenna 21 receives the first code signal including the ID code and the identification code transmitted from the transponder 60 in step S42, the coil antenna 21 outputs the first code signal to the CPU 11, and the CPU 11 extracts the identification code from the first code signal. The type of the electronic key 50 is determined. (Steps S43 to S44)

  At this time, when the transponder 60 receives the wake-up signal, the power circuit 63 generates power by electromagnetic induction, and the power is supplied to the CPU 64. The CPU 64 reads an ID code and an identification code from the EEPROM 61 and transmits a first code signal (ID code and identification code) from the transmission / reception circuit 62.

  In step S44, if the identification code of the received first code signal is “K”, the process proceeds to the registration mode of the normal key 55, and if the identification code is “M”, the process proceeds to the registration mode of the group key 57. (Step S45, Step S46) When the identification code is “T”, since the key is the registration key 56, the registration mode is ended when the ignition switch 22 is turned to the off position. (Step S47)

  Even when the ignition switch 22 is held at the ON position for 15 seconds or longer by the registration key 56, the registration mode is terminated by turning the ignition switch 22 to the OFF position. (Step S37, Step S40)

  First, the registration mode of the normal key 55 will be described based on the flowchart of FIG. In step S36 in FIG. 9, after the registration key 56 is removed, the first normal key 55A that has been turned to turn the ignition switch 22 to the ON position has already passed 2 seconds in step S37, so steps S50 to S52 are performed. The horn does not sound. Then, the wake-up signal is transmitted again to the transponder 60, and the transceiver 20 receives the first code signal (ID code and identification code), thereby identifying the type of the electronic key 50. (Step S52 to Step S55)

  Since the electronic key 50 first determined in step S55 is determined to be the normal key 55 in steps S44 to S45 in FIG. 9, the process directly proceeds to step S56 and the ID code temporarily stored in the RAM 14 is obtained. The number is counted, and if the number that can be registered in the first storage area 12A of the EEPROM 12 has not been reached, the received ID code is temporarily stored in the RAM. (Step S57)

  Then, it is determined whether or not the ignition switch 22 has been turned to the off position within a predetermined time (within 2 to 17 seconds in this embodiment), and after being turned to the off position, within a predetermined time (in this embodiment 1). Within 10 seconds) It is determined whether the next electronic key 50 is inserted and the ignition switch 22 is rotated to the ON position. (Step S58 to Step S61)

  If the ignition switch 22 is held at the ON position for 17 seconds or more despite the horn sounding in step S39 in FIG. 9 or step S51 in FIG. 10, then the ignition switch 22 Is rotated to the off position, the registration mode is terminated as it is, and the information stored in the EEPROM 12 is not changed. (Step S58, Step S62)

  Even when the normal key 55 is rotated to the OFF position in step S60 and the ignition switch is not turned on within a predetermined time (within 10 seconds in the first embodiment), the registration mode is terminated and stored in the EEPROM 12 as it is. The information that has been changed is not changed. (Steps S60 to S61)

  On the other hand, when the conditions of step S58 to step S61 are satisfied, the process returns to step S50, and the ignition switch 22 is turned to the ON position and held for a predetermined time (2 seconds in the first embodiment). In step S51, the horn is blown and the registration process is started.

  That is, in step S52, a wake-up signal is transmitted to the transponder 60, and the transmitter / receiver 20 receives the first code signal (ID code and identification code) transmitted from the transponder 60. The type of key 50 is identified. (Step S50 to Step S55)

  If the electronic key 50 inserted in step S55 is the registration key 56, the ignition switch 22 is turned to the ON position and then turned to the OFF position within a predetermined time (within 2 to 17 seconds in this embodiment). When the turning operation is performed, all the ID codes temporarily stored in the RAM 14 are registered in the EEPROM, and the registration work is completed. (Steps S63 to S65) However, when the ignition switch 22 is kept in the on position for a predetermined time or more in Step S63 and then is turned to the off position, it is temporarily stored in the RAM. The registration mode ends without registering the ID code in the EEPROM. (Step S66)

  Even if the electronic key 50 inserted in step S55 is the group key 57, after the ignition switch 22 is turned to the OFF position within a predetermined time, the ignition key 22 or the registration key 56 is used again for the ignition switch. By setting the position 22 to the ON position, it is possible to return to step 50 and continue the registration work. (Steps S58 to S61) Also in this case, if the ignition switch 22 is kept in the on position for a predetermined time or longer with the group key 57, the information stored in the EEPROM 12 will be stored even if it is subsequently turned to the off position. The registration mode ends without changing. (Steps S58 to S59, Step S62)

  In step S56, when the ID code temporarily stored in the RAM 14 exceeds the number that can be registered in the first storage area 12A of the EEPROM 12, the ID code is not stored and the ID code previously stored in the RAM 14 is stored. Will be registered in the EEPROM 12 only.

  The registration mode of the group key 56 will be described based on the flowchart of FIG. If it is determined in step S45 in FIG. 9 that the electronic key 50 inserted into the key cylinder 23 is the group key 57, the process proceeds to step S70 in FIG. 11, and the CPU 11 activates the transceiver 20 to activate the coil antenna. 21 transmits a group code request signal as an electromagnetic wave. When the transceiver 20 receives the group code transmitted from the transponder 60 in response to the group code request signal, the CPU 11 temporarily stores the group code in the RAM 14. (Step S71)

  Thereafter, in steps S72 to S73, it is determined whether the ignition switch 22 has been turned to the OFF position within a predetermined time (within 2 seconds to 17 seconds in the present embodiment). Even if the predetermined time has elapsed, the ignition switch 22 is determined. If the ignition switch 22 is subsequently turned to the off position, the registration mode is terminated as is. (Step S74)

  On the other hand, the ignition switch 22 is turned to the OFF position within a predetermined time, and the next electronic key 50 is inserted within the predetermined time (10 seconds in this embodiment), so that the ignition switch 22 is turned to the ON position. It is determined whether or not a moving operation has been performed. (Steps S75 to S76) If the electronic key 50 is not inserted into the key cylinder 23 within a predetermined time and the ignition switch 22 is not rotated to the ON position, the registration mode is terminated as it is. (Step S77)

  In step S78 and step S79, it is determined whether the ON position has been held for a predetermined time (in this embodiment, 2 seconds). When 2 seconds have elapsed, the horn sounds and notifies that the registration process has started. (Step S80) Even if the ignition switch 22 is turned to the ON position, if the electronic key 50 is immediately removed, the process proceeds to Step S88, and the registration mode is terminated as it is.

  In the registration process from step S <b> 81, first, a wakeup signal is transmitted from the coil antenna 21. Then, the CPU 11 identifies the inserted electronic key 50 from the ID code and identification code received by the transceiver 20. If the received identification code is an identification code indicating the registration key 56, the received ID code is collated with the ID code registered in the third storage area 12C of the EEPROM 12, and if they match, it is received in step S71. The registered group code is registered in the second storage area 12B of the EEPROM 12, and the registration process is completed when the ignition switch 22 is turned to the OFF position. (Steps S81 to S86)

At this time, since the group code previously registered in the second storage area 12B of the EEPROM 12 is erased, all the previously registered group keys 57 cannot be used.
When the inserted electronic key 50 is a registration key other than the normal key 55, the group key 57, or the registration key 56 registered in the EEPROM 12, the ignition switch 22 is turned to the off position. The registration mode ends, and all group codes temporarily stored in the RAM 14 are erased.

  In the operation mode of the group key 57 capable of producing a plurality of duplicate keys as described above, after receiving the ID code in the immobilizer ECU 10, further requesting the encryption code and storing the received ID code in the EEPROM 12 The encryption code is calculated by performing a predetermined encryption calculation process based on the group code, and the engine start permission signal is output when the encryption code received by the transceiver 20 matches the calculated encryption code. Therefore, even if the encryption code of the group key 57 is read by a third party, the engine 40 cannot be started with only the encryption code, so even when a plurality of group keys 57 are set for one vehicle. Security degradation can be prevented.

  Also, even for the group key 57 of the same vehicle, since the ID code is different for each group key 57, the encryption codes are all apparently different codes. It is possible to prevent the code from being decoded by a third party.

  Furthermore, since this group code is only transmitted from the transponder 60 to the immobilizer ECU 10 at the time of registration, and is not transmitted / received at the time of starting the engine, it is possible to perform cryptographic calculation processing using the group code as a secret key.

  On the other hand, on the manufacturer side, the group code registered in the same vehicle and the ID code registered in each electronic key are subjected to cryptographic calculation processing based on the group code to calculate the cryptographic code, and the cryptographic code is electronically stored. If registered in the key 50, the group key 57 can be easily duplicated.

  Further, since the immobilizer ECU 10 performs cryptographic calculation processing based on the registered group code with the ID code transmitted from the group key 57, the cryptographic code is calculated in the second storage area 12C of the EEPROM 12. Since only the group code that is the basis of the process needs to be registered, a plurality of group keys 57 can be set regardless of the storage capacity of the second storage area 12C of the EEPROM 12.

  As described above, in the first embodiment, the number of normal keys 55 that can be set for one vehicle is limited, and registration can be canceled and new keys can be re-registered for each one. Therefore, even if the electronic key 50 is lost or duplicated, it is possible to prevent unauthorized use by a third party. Therefore, with the normal key 50, the engine can be started only by checking the ID code. It is possible to do this, and it does not have a secret code such as a group code. However, even with the normal key 55, in order to improve security, the ID code is encrypted by performing cryptographic calculation processing based on a random number code or the like transmitted from the vehicle side and transmitted to the vehicle side. Good.

Next, a second embodiment having a group registration key 58 not set in the first embodiment will be described with reference to FIGS.
FIG. 12 is an explanatory diagram showing a registration state of various code signals in the EEPROM of each electronic key including the group registration key, and FIG. 13 is an explanatory diagram showing a registration state of various code signals in the EEPROM on the vehicle side including the group registration key. FIG. 14 is an explanatory diagram showing electronic keys that can be registered for a plurality of vehicle groups including a group registration key including a group registration key.
In addition, about the same part as above-mentioned Example 1, it shows with the same code | symbol and the description is abbreviate | omitted.

  In the invention of the second embodiment, in addition to the normal key 55, the registration key 56 and the group key 57 of the first embodiment described above, it is mounted on a plurality of vehicles (car A, car B, car C) as shown in FIG. The group registration key, which is a common electronic key 50 that can permit the EEPROM 12 of the immobilizer ECU 10 to rewrite or write the ID code of the normal key 55 or the group code of the group key 57 corresponding to each vehicle. 58 is set.

  In the EEPROM 61 of the group registration key 58, as shown in FIG. 12, an ID code (1dx) and an identification code (R) are registered as basic information. As with the group key 57, the same vehicle group (group) is registered. And a group code (Y) registered in common with the electronic key 50 belonging to, and an encryption code (Z1) obtained by performing cryptographic calculation processing based on the group code (Y) on the ID code (1dx) described above ing.

  On the other hand, as shown in FIG. 13, the EEPROM 12 of the immobilizer ECU 10 has three ID codes (1ax, 2ax, 3ax) of the normal key 55 and an ID code (1bx) of the registration key 56 as an identification code (K, T). It is registered to correspond to. The ID codes (1cx, 1dx) of the group key 57 and the group registration key 58 are not registered, and are registered so that the group code (Y) corresponds to the identification code (M, R).

  Similarly to the first embodiment, the storage area where the normal key ID code is registered is the first storage area 12A, the storage area where the group key group code is registered is the second storage area 12B, and the registration key ID code is A storage area to be registered is a third storage area 12C, and a storage area in which a group code of a group registration key is registered is a fourth storage area 12D.

  Further, the group registration key 58 cannot start the engine in the same manner as the registration key 56. Further, similarly to the group key 57, it is possible to set a plurality of necessary numbers for each vehicle.

  The group registration key 58 can register a single group registration key 58 to a plurality of vehicles by the registration process of the group key 57 shown in FIG. At this time, as the group code of the group registration key 59, the fourth storage area 12D corresponding to the identification code “R” is selected and registered.

  Further, when the normal key 55 or the group key 57 is registered in the vehicle using the group registration key 58, the group registration key 58 is inserted into the key insertion hole 24 and the ignition switch 22 is turned to the ON position in the same manner as the registration key 56. Operation. If the CPU 11 of the immobilizer ECU 10 determines in step S4 in FIG. 6 that the identification code of the group registration key 58 is obtained, the CPU 11 performs encryption verification processing in steps S20 to S23 in FIG. If the calculated encryption code matches the calculated encryption code, the process proceeds from step S9 to the registration key operation mode of FIG. Therefore, the registration operation may be performed in the same manner as the registration key 56.

  By setting the group registration key 58 that can perform registration work for such a plurality of vehicles, even when the new normal key 55 or the group key 57 is additionally registered, the group can be obtained without the registration key 56. By possessing one registration key 58, it is possible to easily rewrite or write the EEPROM 12 in the immobilizer ECU 10. Therefore, a vehicle rental company that rents a plurality of vehicles as described above rents them. Vehicle maintenance and management can be made more efficient.

  In the above-described embodiment, the key blade 52 to be inserted into the key insertion hole 24 is provided in the electronic key 50. However, the key cylinder 23 and the key blade 52, which are mechanical lock devices, are eliminated and the transponder 60 is used. The engine start may be permitted only by checking the code signal. In this case, an operation knob is rotatably provided on the steering lock body 25, and an electromagnetic actuator for restricting the rotation of the operation knob is integrally provided on the steering lock body 25, and the code signals are matched. The ignition switch 22 is provided on the electric steering lock that is driven by the electromagnetic actuator and permits the operation knob to rotate.

  Further, when the key blade 52 is provided, the key mountain of the normal key 55 and the registration key 56 is used as a key code for the key cylinder 23 of one specific vehicle (for example, car A), for example, for vehicles of the same vehicle group (group) (for example, The key cylinder 23 of the (B car) may be a general key that cannot be rotated. On the other hand, the key piles of the group key 57 and the group registration key 58 are formed so as to have a common key code in the key cylinders 23 of the same vehicle group (group), and vehicles belonging to a predetermined vehicle group (for example, the vehicle group (Y)). The key cylinder 23 of the vehicle belonging to another vehicle group (for example, the vehicle group (W)) may be a master key that cannot be rotated. .

  In the above-described embodiment, the immobilizer system for a vehicle antitheft device has been described. However, the present invention can also be applied to a non-contact keyless entry for locking and unlocking a vehicle door lock device. In this case, the coil antenna 21 is provided around the door handle, and the electronic key 50 is brought close to the door handle so that the electronic key 50 communicates with the door lock ECU. What is necessary is just to comprise so that locking / unlocking control of a door lock apparatus may be performed by determining coincidence of 50 and ID code or encryption code registered in door lock ECU.

  Moreover, both the immobilizer system of a vehicle antitheft device and the non-contact keyless entry can be set in the vehicle. In this case, the security can be further improved by differentiating the code signals for the immobilizer system and the non-contact keyless entry.

  The present invention can be applied to a case where a plurality of vehicles need to be managed not only for special vehicles such as vehicle construction machines but also for ordinary vehicles such as ordinary passenger cars.

  Furthermore, the present invention can also be applied to a master key system owned by an apartment house management company such as an apartment or an apartment. In this case, the group key is set with the individual key for each room as the normal key and the doors belonging to one apartment or apartment as one group. As a result, the group key can be owned by the management company and the apartment manager as master keys. Therefore, even when the manager is absent, the service person of the management company can unlock the door lock of each door, so that an emergency response can be quickly performed in the event of a disaster.

It is a system block diagram of the immobilizer system for vehicle antitheft based on this invention. It is explanatory drawing which shows the registration state of the various code signals in EEPROM of each electronic key. It is explanatory drawing which shows the registration state of the various code signals in EEPROM on the vehicle side. It is explanatory drawing which shows the electronic key which can be registered with respect to one specific vehicle. It is explanatory drawing which shows the electronic key which can be registered with respect to a some vehicle group. It is a flowchart which shows the control action by the immobilizer ECU side which transfers to each operation mode. It is a flowchart which shows the engine starting control operation by the normal key in the immobilizer ECU side. It is a flowchart which shows the engine starting control operation by the group key in the immobilizer ECU side. It is a flowchart which shows the control operation | movement which transfers to the registration mode by the registration key in the immobilizer ECU side. It is a flowchart which shows the control operation which registers the ID code of the normal key in the immobilizer ECU side. It is a flowchart which shows the control operation | movement which registers the group code of the group key in the immobilizer ECU side. It is explanatory drawing which shows the registration state of the various code signals in EEPROM of each electronic key containing a group registration key. It is explanatory drawing which shows the registration state of the various code signals in EEPROM by the side of a vehicle containing a group registration key. It is explanatory drawing which shows the electronic key which can be registered with respect to the some vehicle group containing a group registration key.

Explanation of symbols

10 Immobilizer ECU (control unit, immobilizer control unit)
12 EEPROM (storage means)
11 CPU (comparison means)
40 Engine (Controlled member)
50 Electronic key 55 Normal key 56 Registration key 57 Group key 58 Group registration key

Claims (4)

An electronic key having a control unit that compares the code signal transmitted from the electronic key with the received code signal and the stored code signal and permits the operation of the controlled member when they match. In the security system used,
An individual key storing an ID code composed of different numbers for each electronic key and an identification code for identifying the function of the electronic key as a code signal;
A group code set for each predetermined group, an encryption code which is calculated by applying the ID code configured individually different numbers predetermined encryption process for each electronic key on the basis of the group code, and the ID code A group key stored as a code signal together with an identification code for identifying the function of the electronic key ;
The control unit includes storage means for storing the various code signals;
When the ID code corresponding to the identification code of the individual key is received as the first code signal, the received ID code is compared with the ID code of the individual key stored in the storage means. When an ID signal corresponding to the identification code of the group key is received as the first code signal while outputting a permission signal for permitting the operation of the controlled member, the received ID code is stored in the storage means. The encryption code is calculated by performing a predetermined encryption process based on the group code, and the calculated encryption code is compared with the encryption code of the group key received as the second code signal. e Bei comparison means for outputting a permission signal for operation permission of the member,
A security system using an electronic key , wherein the storage means of the control unit does not store an ID code of the group key . An electronic key including an immobilizer control unit that compares the code signal transmitted from the electronic key with the received code signal and the stored code signal, and permits the engine start of the vehicle when they match. In the security system used,
An individual key storing an ID code composed of different numbers for each electronic key and an identification code for identifying the function of the electronic key as a code signal;
A group code set for each predetermined group, an encryption code which is calculated by applying the ID code configured individually different numbers predetermined encryption process for each electronic key on the basis of the group code, and the ID code A group key stored as a code signal together with an identification code for identifying the function of the electronic key ;
In the immobilizer control unit, storage means for storing the various code signals;
When the ID code corresponding to the identification code of the individual key is received as the first code signal, the received ID code is compared with the ID code of the individual key stored in the storage means. When an ID signal corresponding to the identification code of the group key is received as the first code signal while outputting a permission signal for permitting engine start of the vehicle, the group code stored in the storage means in the received ID code The encryption code is calculated by performing a predetermined encryption process based on the above, and the calculated encryption code is compared with the encryption code of the group key received as the second code signal. Bei give a comparison means for outputting a permission signal for,
A security system using an electronic key , wherein the storage means of the control unit does not store an ID code of the group key . The storage means is provided with a first storage area for storing an ID code of an individual key and a second storage area for storing a group code of a group key,
3. The security system using an electronic key according to claim 1, wherein the comparison unit selects any storage area according to an identification code and reads a code signal. An individual registration key that stores an ID code composed of individual different numbers for each electronic key, and an identification code indicating a registration function that permits rewriting or writing of various code signals to the storage means, as a code signal;
A registration function for permitting rewriting or writing of various code signals to the storage means, a group code set for each predetermined group, an encryption code calculated by applying predetermined encryption processing to the ID code based on the group code A group registration key that stores an identification code indicating a code signal together with an ID code,
When the comparison means receives the ID code corresponding to the identification code of the registration key as the first code signal, the comparison means compares the ID code of the registration key stored in the storage means and While rewriting or writing the code signal to the storage means is permitted, when an ID code corresponding to the identification code of the group registration key is received as the first code signal, the received ID code is stored in the storage means. The encryption code is calculated by performing a predetermined encryption process based on the group code, and the calculated encryption code is compared with the encryption code of the group registration key received as the second code signal. The rewriting or writing of the code signal to the storage means is permitted. Security system with electronic key.

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