JP4302555B2 - Key device - Google Patents

Description

  The present invention relates to a vehicle key device having an immobilizer function.

  In recent years, an immobilizer system having an immobilizer function (for example, see Patent Documents 1 to 3) has been adopted in vehicles such as automobiles in order to improve the antitheft effect. In this immobilizer system, the engine is allowed to start only when the mechanical identity of the ignition key is obtained and the electronic identity is confirmed.

  Specifically, in the immobilizer system, generally, a key device is provided on the automobile side, and a transponder is embedded in an ignition key for switching the ignition switch to start the engine. The transponder modulates a predetermined password and transmits it. The password signal transmitted from the transponder is received by a key device installed on the vehicle side to determine the identity of the password. Only when the identity is confirmed, a start permission signal is output from the key device to the engine start circuit. As a result, the engine can be started only when the shape of the keyway matches the used ignition key and the identity code is confirmed to be identical.

  Here, the operation of the immobilizer system for confirming the electronic identity of the ignition key will be described in detail. In the key device, when the key detector detects that the ignition key has been inserted into the key insertion port of the ignition cylinder lock, it transmits a key detection signal to the immobilizer circuit in the key device. The immobilizer circuit that has received the key detection signal drives the transmitting / receiving coil on the key device side at a high frequency for a predetermined time by a high frequency circuit including a modulation / demodulation circuit. Then, the transponder-side transmitting / receiving coil embedded in the ignition key is magnetically coupled to the key device-side transmitting / receiving coil, an electric current flows to the transponder side by electromagnetic induction action, and charges are stored in a capacitor provided in the transponder. In the transponder, the charge stored in the capacitor is used as an electromotive force, the code is modulated, and the FM wave is transmitted as a carrier wave from its own transmitting / receiving coil. As a result, the two transmission / reception coils are magnetically coupled again, and a code code signal is transmitted to the high-frequency circuit via the transmission / reception coil on the key device side. In the key device, the received code code signal is demodulated by a high frequency circuit, and the code code is decoded by a control circuit. As a result, a start permission signal is output from the control circuit to the ECU of the engine only when the identity of the password is determined. Thereby, the electronic identity of the ignition key is confirmed. Here, the key detection signal is also transmitted to the central control unit of the automobile and used in various controls of the central control unit.

  Also, in some key devices, as a trigger for high-frequency driving of the transmission / reception coil on the key device side, a key that triggers when the ignition switch is switched to the ON position without using the key detection signal from the key detector. There is also a device. Even in this case, as described above, the key detector transmits the fact that it has been inserted into the key device to the central controller of the automobile.

JP-A-10-81203 Japanese Patent No. 2624187 Japanese Patent No. 3151128

  By the way, in the key device of such an immobilizer system, the circuit board on which the immobilizer circuit is mounted and the key detector are arranged around the key insertion hole, respectively, but are arranged separately. This is because the key detector was originally provided in the key device to communicate to the central control part of the car that the key was inserted into the key device before the immobilizer system was developed. This is because the immobilizer system is also used when adopting the immobilizer system.

  However, since the circuit board and the key detector are provided separately, there is a problem that the use efficiency of the space is poor. In addition, both of these are electrical components of the key device, but since they are provided separately, there is a problem that the assembly work is complicated.

  The objective of this invention is providing the key apparatus which can improve the usage efficiency of a space.

  The objective of this invention is providing the key apparatus which can aim at the improvement of assembly property.

According to the first aspect of the present invention, a key detector that detects insertion of a key into a key insertion slot of a cylinder lock and outputs a key detection signal from a terminal, and a transmission / reception coil for the key inserted into the key insertion slot are used. In a key device comprising: a circuit board on which an immobilizer circuit that executes a password transmission operation to acquire a password, determines whether the password is correct, and outputs a signal according to the determination result is provided. A key detector and the circuit board are attached to a single casing, the terminals of the key detector are connected to the circuit board , fitted to the outside of the key insertion port, and the transmission / reception coil is held to The coil holding part which positions a transmission / reception coil around the said key insertion port, and the hinge part which connects this coil holding part and the said casing rotatably are provided .

According to a second aspect of the invention, in the key device of claim 1, leave the connection portion extending from the wound portion to the coil holding portion is connected to the circuit board of the transceiver coil from the key detector A positioning relay part for positioning at a different position.

According to a third aspect of the present invention, the key device according to the first or second aspect further includes a defense wall that covers the key detector upstream of the key detector in the key insertion direction and protects the key detector.

According to the first aspect of the present invention, a key detector that detects the insertion of the key into the key insertion slot of the cylinder lock and outputs a key detection signal from the terminal, and a transmission / reception coil for the key inserted into the key insertion slot are used. In a key device comprising: a circuit board on which an immobilizer circuit that acquires a personal identification number by executing a transmission operation of a personal identification number, determines whether the personal identification number is correct, and outputs a signal according to the determination result is provided. A key detector and the circuit board are attached to a single casing, the terminals of the key detector are connected to the circuit board , fitted to the outside of the key insertion port, and the transmission / reception coil is held to a coil holder to position the receiving coil around the key insertion opening, and a hinge portion connecting the casing and the coil holding portion rotatably, by providing, in the key device It is possible to improve the use efficiency of the pace. Further, the assembling property of the key device can be improved. Moreover, the mounting operation of the casing and the coil holding part can be facilitated.

According to a second aspect of the present invention, in the key device according to the first aspect , a connection portion that extends from a portion of the transmission / reception coil wound around the coil holding portion and is connected to the circuit board is connected to the key detector. By providing a positioning relay part that positions at a position away from the transmission / reception coil 13, when the transmission / reception coil 13 is assembled, the transmission / reception coil can be wired in the casing via a position away from the key insertion port. The coil can be easily wired without interfering with the key detector.

According to a third aspect of the present invention, in the key device according to the first or second aspect , the protective wall that covers the key detector and protects the key detector upstream of the key detector in the key insertion direction. By providing, since the key detector is protected by the defense wall, it is prevented that the key detector 14 is destroyed.

  An embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a perspective view showing an external structure of an automobile immobilizer system 1 according to the present embodiment. As shown in FIG. 1, an immobilizer system 1 includes a key device 3 connected to an ignition switch 2 and provided in an automobile (not shown), a key unit 5 that is a key incorporating a transponder 4 (see FIG. 5), and the like. It is configured. Each will be described in detail below.

  The ignition switch 2 is configured on the basis of four contacts for ignition. There are four types of contacts, LOCK, ACC, ON, and ST, which are generally used. The LOCK position is the only position that does not supply power to at least the parts other than the key device 3 and allows an ignition key 8 (described later) of the key unit 5 to be inserted into and removed from a key insertion slot 7 of a cylinder lock 6 (described later). is there. The ACC position is a position that allows power supply to accessories such as a radio and a power window. The ON position is a position that allows power supply to all electric and electronic components including the engine control block (ECU). The ST position is a position for driving the engine starter to start the engine, and the ignition key 8 located at the ST position is returned to the ON position by the force of a return spring (not shown).

  2 is a vertical side view showing the key device 3, FIG. 3 is a vertical side view showing the key device 3 with the key unit 5 inserted therein, FIG. 4 is an exploded perspective view showing the key device 3, and FIG. 5 is an immobilizer system. 1 is a block diagram showing a simplified circuit configuration of FIG.

  As shown in FIGS. 2 to 5, the key device 3 includes a cylinder lock 6, an immobilizer unit 9, and the like. The cylinder lock 6 is formed with a key insertion slot 7 into which an ignition key 8 described later is inserted. The body 10 of the cylinder lock 6 also serves as the body of the well-known steering lock mechanism 11. The steering lock mechanism 11 is a mechanism that locks the steering when the ignition key 8 is in the LOCK position.

  The immobilizer unit 9 includes an immobilizer circuit 12, a transmission / reception coil 13, a key detector 14, and the like.

  The immobilizer circuit 12 includes an RF circuit (RF: Radio Frequency) 15 as a high frequency circuit and a control circuit 16 and is mounted on a circuit board 17. The control circuit 16 is connected to an EEPROM (Electrically Erasable Programmable Read Only Memory) 18 as a memory for storing the password, and the EEPROM 18 also constitutes the immobilizer circuit 12. The RF circuit 15 is supplied with power from a battery (not shown) of the automobile to drive the transmission / reception coil 13 at a high frequency, and a security code as a security code obtained by demodulating the security code signal received from the transponder 4 via the transmission / reception coil 13. Is a high-frequency circuit having a function of outputting the signal to the control circuit 16. The control circuit 16 includes a microcomputer including a CPU and a memory (not shown). The control circuit 16 is connected to the ECU of the engine via a connector 19 attached to the circuit board 17. The control code 16 calls the security code from the EEPROM 18, and the called security code and the security code demodulated by the RF circuit 15. When the two collation codes are determined to match, a start permission signal is output to the engine ECU.

  6 is a longitudinal side view showing the immobilizer unit 9, FIG. 7 is a front view thereof, FIG. 8 is an exploded view showing the structure of the key detector 14, and FIG. 9 is an exploded view showing the key device 3. In FIG. 7, a part of FIG. 6 is omitted.

  As shown in FIGS. 4 and 6 to 9, the circuit board 17 is housed and held in a casing-shaped resin casing 20. The casing 20 is attached to the upper outer periphery of the body 10 of the cylinder lock 6. The casing 20 includes a casing body 20a and a cover 20b that is click-stopped by the casing body 20a. The circuit board 17 is accommodated in the casing 20 by housing the circuit board 17 in the casing body 20a and closing the cover 20b. It is comprised so that it may be fixedly accommodated in. The connector 19 is also provided integrally with the casing 20.

  The transmission / reception coil 13 is wound and held in a ring-shaped coil holding portion 21 that fits outside the key insertion port 7 of the cylinder lock 6. The coil holding part 21 is made of resin and is integrally formed with the casing 20. A bendable hinge portion 22 is formed between the coil holding portion 21 and the casing 20. By this hinge part 22, the coil holding | maintenance part 21 and the casing 20 are connected mutually rotatably. The coil holding part 21 attached to the cylinder lock 6 is substantially perpendicular to the casing 20.

  The transmission / reception coil 13 includes a winding part 13 a wound around the coil holding part 21 and a connection part 13 b extending from the winding part 13 a and connected to the circuit board 17. The connection portion 13b is connected to the circuit board 17 via a positioning relay portion 23 provided integrally with the coil holding portion 21. The positioning relay part 23 is provided obliquely above the coil holding part 21 and in the middle between the coil holding part 21 and the circuit board 17 and includes a hole 23a around which the connection part 13b is wound. The coil holding part 21 positions the connecting part 13 b at a position away from the key detector 14, the coil holding part 21 and the circuit board 17.

  The key detector 14 is integrally attached to the casing 20. The key detector 14 is schematically configured such that a slider 32 is slidably fitted in a vertical direction to a slider holding portion 31 of a lower surface opening formed in the casing 20 above the key insertion port 7 of the cylinder lock 6. Has been. The slider holding portion 31 is formed with a pair of grooves 31 a that are long in the vertical direction and slidably engage with a pair of claw portions 32 a that are formed to project from the side surface of the slider 32. In the figure, only one groove 31a is shown. A stopper portion 31b with which the claw portion 32a of the slider 32 abuts from above is formed below the groove portion 31a. A compression coil spring 33 is provided between the upper surface of the slider 32 and the ceiling surface of the slider holding portion 31. A fixed contact 34 is provided on the inner peripheral surface of the slider holding portion 31, and a movable contact 35 is provided on the side surface of the slider 32. The fixed contact 34 is connected to the immobilizer circuit 12 via an external terminal 36 that is a terminal.

  The slider 32 of the key detector 14 moves up and down when the insertion / removal operation of the ignition key 8 with respect to the key insertion slot 7 is transmitted via the transmission mechanism 51 shown in FIGS. The transmission mechanism 51 is provided on the cylinder lock 6, and a rotation block 53 that rotates up and down around a fulcrum 52, a lock lever 55 that can rotate around a fulcrum 54, and one end side of the lock lever 55 at the rotation block 53. It is comprised from the compression coil spring 56 etc. which are urged | biased to the side. In this transmission mechanism 51, when the ignition key 8 is not inserted into the key insertion slot 7, the one end side of the lock lever 55 and the rotation block 53 are rotated downward by the compression coil spring 56. At this time, the slider 32 is urged by the compression coil spring 33 and is positioned below the slider holding portion 31. In this state, the movable contact 35 and the fixed contact 34 are separated from each other. When the ignition key 8 is inserted into the key insertion slot 7, the rotation block 53 is pushed by the ignition key 8 and rotates upward. With this rotation, one end side of the lock lever 55 is biased by the compression coil spring 56. It is rotated against. Then, the slider 32 pushed to one end of the lock lever 55 moves upward against the compression coil spring 33, and the movable contact 35 is connected to the fixed contact 34. As a result, a key detection signal is output from the key detector 14 to the immobilizer circuit 12. In this state, when the ignition key 8 is removed from the key insertion slot 7, the slider 32 moves downward, the movable contact 35 is detached from the fixed contact 34, and a key release signal is output to the immobilizer circuit 12.

  The other end side of the lock lever 55 is connected to the lock bolt 57 of the steering lock mechanism 11. The lock bolt 57 protrudes from the body 10 when the cylinder lock 6 is rotated to the LOCK position, and locks a steering shaft (not shown). Further, when the ignition key 8 is inserted, the lock lever 55 is engaged with the lock bolt 57, and the lock bolt 57 is held in the retracted position, so that inadvertent locking of the steering during operation is prevented. .

  A defense wall 58 that covers the key detector 14 is provided on the upstream side of the key detector 14 in the insertion direction of the ignition key 8. The defense wall 58 has a shape protruding upward from the body 10 and is formed integrally with the body 10. The defense wall 58 is inserted into a notch 20c formed in the lower portion of the front end portion of the casing body 20a, and is positioned in front of the key detector 14. By this protective wall 58, the key detector 14 is protected forward (upstream side of the ignition key 8 insertion side).

  Next, the key unit 5 will be described. As shown in FIG. 1, the key unit 5 has an external configuration as an ignition key 8, and a transponder 4 shown in FIG. The transponder 4 incorporates a transmission / reception coil (not shown) that is magnetically coupled to the transmission / reception coil 13 on the key device 3 side that is driven at high frequency, and stores the electric power generated by the electromagnetic induction effect due to such magnetic coupling as a charge in a capacitor (not shown). The PIN code is modulated using the electric charge stored in the capacitor as an electromotive force, and the FM wave is transmitted as a carrier wave from a built-in transmission / reception coil.

  The operation of the immobilizer system 1 will be described. First, the driver inserts the ignition key 8 of the key unit 5 into the key insertion port 7 of the cylinder lock 6 in order to start the engine of the automobile. As a result, the key detector 14 detects the insertion of the ignition key 8 into the key insertion slot 7, and a key detection signal is input to the immobilizer circuit 12. In the immobilizer circuit 12 to which the key detection signal is input, the RF circuit 15 is activated for a predetermined time and the transmission / reception coil 13 is driven at a high frequency. As a result, a magnetic field is generated around the transmission / reception coil 13, and the transmission / reception coil 13 and the transmission / reception coil built in the transponder 4 are magnetically coupled. Then, the transmission / reception coil built in the transponder 4 receives an electromagnetic induction action, and charges are stored in the capacitor of the transponder 4. Here, the predetermined time when the RF circuit 15 is activated is a time required to sufficiently store electric charges in the capacitor of the transponder 4. Therefore, after the electric charge is sufficiently stored in the capacitor of the transponder 4, the power supply to the transponder 4 is stopped, and thereby the potential of the capacitor is slightly lowered. The transponder 4 detects such a potential drop of the capacitor, uses this as a trigger to modulate the code code signal, and transmits and outputs the code code signal modulated using the FM wave as a carrier wave. As a result, the transmission / reception coil built in the transponder 4 and the transmission / reception coil 13 on the key device 3 side are magnetically coupled, and the code signal is received by the RF circuit 15 of the key device 3. Therefore, the RF circuit 15 demodulates the received code code signal and sends it to the control circuit 16. The control circuit 16 decodes the code code signal to obtain a code code as a code number, which is stored in the EEPROM 18. Check with the PIN code as the PIN. As a result of the collation, when it is determined that the two passwords match, the control circuit 16 outputs a start permission signal to the ECU of the engine. Thereby, starting of the engine is permitted. When the mechanical identity of the ignition key 8 and the cylinder lock 6 is obtained, the cylinder lock can be rotated. When the cylinder lock 6 is rotated to the ST position, the ignition switch 2 starts the engine start operation. Is done.

  As described above, in the key device 3 of the present embodiment, the key detector 14 and the circuit board 17 are attached to the single casing 20, and the external terminal 36 that is a terminal of the key detector 14 is attached to the circuit board 17. By connecting, the key detector 14 and the circuit board 17 are integrated together, so that the space use efficiency is improved. Thereby, the key apparatus 3 can be arrange | positioned in a small space. Moreover, since the circuit board 17 which is an electrical component of the key device 3 and the key detector 14 are integrated, the assembling property of the key device 3 can be improved.

  Further, when the casing 20 is attached to the body 10 by connecting the coil holding part 21 and the casing 20 so as to be rotatable by the hinge part 22, the coil holding part 21 is made horizontal with respect to the casing 20 Interference between the cylinder lock 6 and the coil holding portion 21 is avoided, thereby facilitating attachment of the casing 20. Then, by bending the coil holding portion 21 with respect to the casing 20, the coil holding portion 21 can be easily attached to the cylinder lock 6 while avoiding the protective wall 58.

  Further, since the connection portion 13b of the transmission / reception coil 13 is positioned at a position away from the key detector 14 by the positioning relay portion 23, the transmission / reception coil 13 is separated from the key insertion port 7 when the transmission / reception coil 13 is assembled. Therefore, the transmission / reception coil 13 can be easily wired without interfering with the key detector 14.

  Further, by providing a protective wall 58 that covers the key detector 14 and protects the key detector 14 on the upstream side of the key detector 14 in the insertion direction of the ignition key 8, for example, the driver inserts the ignition key 8 into the key insertion slot. 7, even if the key detector 14 is accidentally applied to the upper portion of the key insertion slot 7, the key detector 14 is protected by the protective wall 58, so that the key detector 14 is prevented from being destroyed. The

  In the present embodiment, the mode in which the RF circuit 15 drives the transmission / reception coil 13 at a high frequency at the timing when the ignition key 8 is detected to be inserted into the key insertion slot 7 of the cylinder lock 6 has been described. Is configured to detect that the cylinder lock 6 is rotated to the ST position after the ignition key 8 is inserted into the key insertion port 7 of the cylinder lock 6 and to drive the transmission / reception coil 13 at a high frequency at this timing. May be.

It is a perspective view which shows the external appearance structure of the immobilizer system of one embodiment of this invention. It is a vertical side view which shows a key apparatus. It is a vertical side view which shows the key apparatus of the state in which the key unit was inserted. It is a disassembled perspective view which shows a key apparatus. It is a block diagram which simplifies and shows the circuit structure of an immobilizer system. It is a vertical side view which shows an immobilizer part. It is the front view. It is an exploded view which shows the structure of a key detector. It is an exploded view which shows a key apparatus.

Explanation of symbols

3 Key device 5 Key unit (key)
6 Cylinder lock 7 Key insertion slot 12 Immobilizer circuit 13 Transmission / reception coil 13b Connection part 14 Key detector 17 Circuit board 20 Casing 21 Coil holding part 22 Hinge part 23 Positioning relay part 36 Terminal (external terminal)
58 Defense Wall

Claims (3)

A key detector that detects the insertion of the key into the key insertion port of the cylinder lock and outputs a key detection signal from the terminal, and a transmission of a password using a transmission / reception coil for the key inserted into the key insertion port. A circuit board equipped with an immobilizer circuit that acquires a personal identification number and determines whether the personal identification number is correct and outputs a signal according to the determination result.
Attaching the key detector and the circuit board to a single casing, connecting the terminals of the key detector to the circuit board ,
A coil holding portion that fits outside the key insertion slot, holds the transmission / reception coil, and positions the transmission / reception coil around the key insertion slot;
A hinge portion that rotatably connects the coil holding portion and the casing;
Key device, characterized in that it comprises a. The positioning relay part which positions the connection part extended from the part wound by the said coil holding part of the said transmission / reception coil and connected to the said circuit board in the position away from the said key detector is characterized by the above-mentioned. The key device according to 1 . It said key detector said key detector covering said key detector key device according to claim 1 or 2, characterized in that it comprises a protective wall that protects the upstream side of the key insertion direction than.

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