JP5774947B2 - Electronic key system - Google Patents

Description

  The present invention relates to an electronic key system.

  In the conventional electronic key system, locking / unlocking of the vehicle door, engine starting, and the like are permitted through wireless communication between the electronic key and the vehicle. For example, in the electronic key system disclosed in Patent Document 1, the vehicle transmits a request signal to the outside of the vehicle interior. When the electronic key receives the request signal, the electronic key transmits a response signal including the ID code. The vehicle permits the locking and unlocking of the vehicle door when it is determined that the verification of the ID code included in the response signal from the electronic key existing outside the vehicle is established. On the other hand, the vehicle permits the start of the engine when it is determined that the verification of the ID code included in the response signal from the electronic key present in the vehicle has been established.

  In the above electronic key system, when the battery of the electronic key is dead, communication with the vehicle through the electronic key and thus unlocking of the door cannot be executed. Thus, for example, in the electronic key described in Patent Document 2, an emergency mechanical key is housed in the electronic key body. That is, when the battery runs out, the vehicle key can be locked and unlocked by taking out the mechanical key from the electronic key body and turning the mechanical key inserted into the keyhole of the vehicle door. Thereby, when the battery of the electronic key is exhausted, it is possible to prevent a situation in which the user cannot get on.

  Further, for example, in the electronic key system described in Patent Document 3, even when the battery of the electronic key is exhausted, the electronic key can start the engine through wireless communication with the vehicle. In this configuration, when the battery of the electronic key runs out, the engine can be started through transponder communication by holding the electronic key over a specific position (for example, an engine switch). In this transponder communication, the electronic key transmits a radio signal including an ID code to the vehicle by induced power generated based on a trigger signal from the vehicle. That is, battery power is not required for transmission of this radio signal.

  As described above, even when the battery of the electronic key is exhausted, the vehicle door can be locked and unlocked and the engine can be started.

JP 2002-029385 A JP 2010-120413 A JP 2010-12921 A

  As described above, when the battery of the electronic key is dead, the vehicle door is locked and unlocked, and the engine needs to be started differently from the normal operation. In particular, the engine starting method in the case of running out of the battery is special compared to the method for locking and unlocking the vehicle door in the case of running out of the battery. For this reason, there is a possibility that the engine start method when the battery of the electronic key runs out is not recognized by the user. Therefore, there is a possibility that the engine cannot be started when the battery of the electronic key is exhausted. Under such circumstances, there is a need for an electronic key that is less likely to run out of battery, that is, has reduced power consumption related to communication with an in-vehicle device.

  The present invention has been made in view of such circumstances, and an object thereof is to provide an electronic key system in which power consumption of an electronic key related to communication with an in-vehicle device is reduced.

Hereinafter, means for achieving the above-described object and its operation and effects will be described.
The invention according to claim 1 comprises: an in-vehicle device that transmits a request signal to the inside and outside of a vehicle; and an electronic key that transmits a response signal including an ID code when the request signal is received. When the validity of the response signal is confirmed, in the electronic key system that permits switching of the locking / unlocking state of the vehicle door or starting of the engine, the electronic key has power for receiving the request signal and transmitting the response signal. Battery voltage detection means for detecting the voltage of the battery to be stored is provided, the in-vehicle device transmits the first request signal or the second request signal as the request signal, and the electronic key is connected to the battery voltage through the battery voltage detection means. Is determined to be greater than or equal to a threshold value, the first request signal or the second request Sends said response signal upon receiving the items, when the battery voltage through the battery voltage detecting means is determined that is less than the threshold value, transmits the response signal only when it receives the second request signal, The in-vehicle device transmits the first request signal to the outside of the vehicle, transmits the second request signal to the inside of the vehicle, and confirms the validity of the response signal with respect to the first request signal. The gist is to allow the engine to start when the lock is permitted and the validity of the response signal with respect to the second request signal is confirmed .

According to this configuration, when the battery voltage of the electronic key becomes less than the threshold value, a response signal is transmitted only for the second request signal. That is, when the battery voltage is less than the threshold value, a response signal is prevented from being transmitted with respect to the first request signal. Therefore, the power consumption of the electronic key related to communication with the in-vehicle device can be reduced.
Here, when the battery voltage of the electronic key becomes less than the threshold value, the response signal is transmitted only to the second request signal transmitted into the vehicle. Therefore, when the battery voltage of the electronic key is lowered, communication related to unlocking the vehicle door is executed, so that the power of the battery is consumed and the engine cannot be started.

According to a second aspect of the present invention, in the electronic key system according to the first aspect of the present invention, the electronic key system includes a power generation device that generates power using externally applied energy and charges the generated power to the battery. It is a summary.

  According to this configuration, the battery is charged with power through the power generator. For this reason, it becomes possible to prevent the vehicle door from being locked or unlocked or the engine from being disabled through the electronic key system due to a decrease in battery voltage.

According to a third aspect of the present invention, in the electronic key system according to the second aspect , the mechanical key is removably accommodated in the main body of the electronic key and can be mechanically switched between a locked state and an unlocked state of the vehicle door. The gist of the power generation apparatus is to generate power using energy generated when the mechanical key is taken out.

  For example, if the vehicle door cannot be locked and unlocked through the electronic key due to a decrease in the battery voltage of the electronic key, the mechanical key is taken out from the main body of the electronic key by the user. At this time, the battery is charged with power through the power generator. The charged electric power is used for communication related to engine start, so that the engine can be started more reliably.

According to a fourth aspect of the present invention, in the electronic key system according to any one of the first to third aspects of the present invention, the electronic key system includes an engine switch provided in the vicinity of a driver's seat so as to be operable by a user. When it is recognized that the switch has been operated, the gist is to allow the engine to start when the second request signal is transmitted into the vehicle and the validity of the response signal with respect to the second request signal is confirmed. .

According to this configuration, when the battery voltage of the electronic key is less than the threshold value, a response signal is transmitted from the electronic key only when the engine switch is operated. Therefore, the power consumption of the electronic key related to communication with the in-vehicle device can be reduced.
The invention according to claim 5 comprises: an in-vehicle device that transmits a request signal to the inside and outside of a vehicle; and an electronic key that transmits a response signal including an ID code when the request signal is received. When the validity of the response signal is confirmed, in the electronic key system that permits switching of the locking / unlocking state of the vehicle door or starting of the engine, the electronic key has power for receiving the request signal and transmitting the response signal. Battery voltage detection means for detecting the voltage of the battery to be stored is provided, the in-vehicle device transmits the first request signal or the second request signal as the request signal, and the electronic key is connected to the battery voltage through the battery voltage detection means. Is determined to be greater than or equal to a threshold value, the first request signal or the second request When the signal is received, the response signal is transmitted, and when the battery voltage detection means determines that the battery voltage is less than the threshold value, the response signal is transmitted only when the second request signal is received, In addition, the power generation device includes a power generation device that generates power using energy applied from the outside and charges the generated power to the battery. The gist includes a mechanical key that can be switched between a locked state and an unlocked state, and the power generation device uses the energy generated when the mechanical key is taken out to generate power.
According to this configuration, when the battery voltage of the electronic key becomes less than the threshold value, a response signal is transmitted only for the second request signal. That is, when the battery voltage is less than the threshold value, a response signal is prevented from being transmitted with respect to the first request signal. Therefore, the power consumption of the electronic key related to communication with the in-vehicle device can be reduced.
In addition, the battery is charged with power through the power generator. For this reason, it becomes possible to prevent the vehicle door from being locked or unlocked or the engine from being disabled through the electronic key system due to a decrease in battery voltage.
Further, for example, when the vehicle door cannot be locked and unlocked through the electronic key due to a decrease in battery voltage of the electronic key, the mechanical key is taken out from the main body of the electronic key by the user. At this time, the battery is charged with power through the power generator. The charged electric power is used for communication related to engine start, so that the engine can be started more reliably.

  ADVANTAGE OF THE INVENTION According to this invention, the power consumption of the electronic key which concerns on communication with a vehicle-mounted apparatus can be reduced in an electronic key system.

The block diagram of the electronic key system in 1st Embodiment. The top view of the vehicle in a 1st embodiment. The flowchart which shows the process sequence of the vehicle-mounted control apparatus and electronic key control part in 1st Embodiment. The flowchart which shows the process sequence of the vehicle-mounted control apparatus and electronic key control part in 2nd Embodiment.

(First embodiment)
A first embodiment of an electronic key system according to the present invention will be described below with reference to FIGS. As shown in FIG. 1, the electronic key system 1 includes an electronic key 10 possessed by a user and an in-vehicle device 20 mounted on the vehicle 2. Hereinafter, the configuration of the electronic key 10 and the in-vehicle device 20 will be described.

<Electronic key>
As shown in FIG. 1, an electronic key 10 includes an electronic key control unit 11 constituted by a computer unit, an LF receiving unit 12 that receives a radio signal in an LF (Low Frequency) band, and an UHF (Ultra High Frequency) band. The UHF transmitter 13 for transmitting the radio signal and the battery unit 15 for supplying power to each unit.

  The battery unit 15 includes a rechargeable secondary battery. Further, the battery unit 15 includes a voltage sensor 15 a that detects its own battery voltage, and the detection result of the voltage sensor 15 a is output to the electronic key control unit 11. The electronic key control unit 11 recognizes the battery voltage based on the detection result of the voltage sensor 15a.

  The LF receiving unit 12 receives the first request signal Srs1 or the second request signal Srs2 from the in-vehicle device 20 via its own receiving antenna 12a. In this example, the first request signal Srs1 is a radio wave transmitted outside the vehicle, and the second request signal Srs2 is a radio wave transmitted inside the vehicle. The LF receiver 12 demodulates the first request signal Srs1 or the second request signal Srs2 into a pulse signal and outputs it to the electronic key control unit 11.

  The electronic key control unit 11 includes a nonvolatile memory 11a. The memory 11a stores an ID code unique to the electronic key 10 and a threshold value regarding determination of a battery voltage drop. When the electronic key control unit 11 recognizes the first request signal Srs1, the electronic key control unit 11 recognizes the battery voltage through the voltage sensor 15a. When the electronic key control unit 11 determines that the battery voltage is equal to or higher than the threshold value, the electronic key control unit 11 outputs a response signal including the ID code stored in the memory 11 a to the UHF transmission unit 13. The UHF transmitter 13 modulates the response signal and transmits it as a UHF band radio signal via the transmission antenna 13a. On the other hand, when it is determined that the battery voltage is less than the threshold value, the electronic key control unit 11 does not generate a response signal even if it receives the first request signal Srs1.

  When the electronic key control unit 11 recognizes the second request signal Srs2, the electronic key control unit 11 outputs a response signal including the ID code stored in the memory 11a to the UHF transmission unit 13. The UHF transmitter 13 modulates the response signal and transmits it as a UHF band radio signal via the transmission antenna 13a.

  The main body of the electronic key 10 houses an emergency mechanical key 17. Furthermore, a power generation device 18 that generates power by inserting and removing the mechanical key 17 is provided. In this example, this insertion / extraction force is external energy for the power generation device 18. The linear motion of the mechanical key 17 accompanying the insertion / extraction is converted into a rotational motion by the power generator 18. The power generator 18 generates power based on this rotational motion. The electric power generated through the power generation device 18 is charged in the battery unit 15.

  The mechanical key 17 taken out is inserted into a key cylinder (not shown) provided on the vehicle door. In this state, the mechanical key 17 is rotated. Thereby, the locking / unlocking state of the vehicle door is switched.

  The electronic key 10 includes a transponder 14. The transponder 14 includes a coil and an IC chip. When this transponder 14 receives a driving radio wave that is locally transmitted in the vicinity of an engine switch operated when the engine is started, an induced power is generated in its coil. Based on this power, the transponder 14 transmits a transponder response signal including its own ID code. At this time, the power of the battery unit 15 is not used.

<In-vehicle device>
As shown in FIG. 1, the in-vehicle device 20 includes an in-vehicle control unit 21 configured by a computer unit, an out-of-vehicle transmission unit 22 that transmits an LF band radio signal to the outside of the vehicle, and an LF band radio signal in the vehicle. And a vehicle-mounted receiving unit 24 for receiving a UHF band radio signal transmitted from inside and outside the vehicle.

  In addition, an engine switch 33, a door lock device 34, an engine device 35, a lock switch 36, and a courtesy switch 37 are electrically connected to the in-vehicle control unit 21.

  As shown enlarged in the circle of FIG. 2, the lock switch 36 is provided on the door handle 4 on the outside of the vehicle and is pushed when the vehicle door is locked and unlocked. As shown in FIG. 1, the lock switch 36 outputs an operation signal indicating that it has been operated to the in-vehicle control unit 21.

  The engine switch 33 is provided in the vicinity of the driver's seat and is pushed when the engine is started. The engine switch 33 outputs an operation signal indicating that it has been operated to the in-vehicle control unit 21.

The courtesy switch 37 detects the open / closed state of the vehicle door and outputs the detection result to the in-vehicle control unit 21.
The in-vehicle control unit 21 includes a nonvolatile memory 21a, and the same ID code as the ID code of the electronic key 10 is stored in the memory 21a.

  When the vehicle door is in a locked state, the in-vehicle control unit 21 generates a first request signal Srs1 at regular intervals, and outputs it to the outside transmission unit 22. As shown in an enlarged manner in the circle of FIG. 2, the vehicle exterior transmission unit 22 is provided inside the door handle 4 on the vehicle exterior side. The outside transmission unit 22 modulates the first request signal Srs1 and transmits it as an LF band radio signal via the outside transmission antenna 22a.

  When the vehicle-mounted control unit 21 recognizes that the vehicle door is opened and closed through the courtesy switch 37 after unlocking the vehicle door, the vehicle-mounted control unit 21 generates the second request signal Srs2 and outputs it to the in-vehicle transmission unit 23. Different identification codes are added to the request signals Srs1 and Srs2, respectively. Alternatively, both signals may be identified by changing the Wake code pattern in both request signals Srs1 and Srs2.

As shown in FIG. 2, the in-vehicle transmitter 23 is provided in the vehicle. The in-vehicle transmission unit 23 modulates the second request signal Srs2 and transmits it to the in-vehicle via the in-vehicle transmission antenna 23a.
As shown in FIG. 1, when the in-vehicle receiving unit 24 receives a response signal transmitted from the electronic key 10 via the receiving antenna 24a, the in-vehicle receiving unit 24 demodulates this signal into a pulse signal and outputs it to the in-vehicle control unit 21.

  The in-vehicle control unit 21 collates the ID code included in the received response signal with the ID code stored in the memory 21a. When the vehicle-mounted control unit 21 recognizes that the lock switch 36 has been pressed in a state where ID verification (external vehicle verification) of the response signal with respect to the first request signal Srs1 has been established, Switch the lock state.

  When the in-vehicle control unit 21 recognizes that the engine switch 33 has been pressed within a certain period of time after the ID verification (in-vehicle compartment verification) of the response signal for the second request signal Srs2 is established, Start.

  The in-vehicle device 20 includes an immobilizer communication device 25. The immobilizer communication device 25 is built in the engine switch 33. The vehicle-mounted control unit 21 outputs a command signal to the immobilizer communication device 25, for example, when the brake pedal is depressed while the engine is stopped. The immobilizer communication device 25 transmits a driving radio wave based on a command signal from the in-vehicle control unit 21. This driving radio wave is locally transmitted in the vicinity of the engine switch 33. When the electronic key 10 is held over the engine switch 33, the transponder 14 of the electronic key 10 is activated by receiving the driving radio wave. Then, the transponder 14 transmits a transponder response signal including the ID code. When receiving the transponder response signal, the immobilizer communication device 25 demodulates this signal into a pulse signal and outputs it to the in-vehicle control unit 21. The in-vehicle controller 21 collates the ID code included in the transponder response signal with the ID code stored in the memory 21a (transponder collation). When the in-vehicle control unit 21 recognizes that the engine switch 33 is pushed in a state where the transponder verification is established, the in-vehicle control unit 21 starts the engine through the engine device 35.

  Next, processing procedures of the in-vehicle control unit 21 and the electronic key control unit 11 will be described with reference to the flowchart of FIG. Note that the battery voltage of the battery unit 15 in the electronic key 10 of this example is less than the threshold value.

  When the vehicle door is in the locked state, the in-vehicle control unit 21 transmits the first request signal Srs1 to the outside of the vehicle at regular intervals (S101). When receiving the first request signal Srs1, the electronic key control unit 11 determines that the battery voltage of the battery unit 15 is less than the threshold value (S102), and does not transmit a response signal. In this case, the user takes out the mechanical key 17 from the main body of the electronic key 10 and uses the mechanical key 17 to unlock the vehicle door. When the mechanical key 17 is removed from the main body of the electronic key 10, the electric power generated through the power generation device 18 is charged into the battery unit 15.

  After recognizing the unlocking of the vehicle door through the mechanical key 17 (S103), the in-vehicle control unit 21 recognizes the opening / closing of the vehicle door (S104), and transmits the second request signal Srs2 (S105). When receiving the second request signal Srs2, the electronic key control unit 11 transmits a response signal regardless of the battery voltage (S106). At this time, the electric power charged through the power generator 18 is used. This completes the processing of the electronic key control unit 11.

  The in-vehicle control unit 21 determines that collation (in-vehicle collation) between the ID code included in the received response signal and the ID code stored in the memory 21a has been established (S107). When the in-vehicle control unit 21 determines that the engine switch 33 has been operated in a state where the vehicle interior verification is established (S108), the vehicle-mounted control unit 21 starts the engine (S109). Thereby, the process of the vehicle-mounted control part 21 is complete | finished.

As described above, according to the embodiment described above, the following effects can be obtained.
(1) When the battery voltage of the electronic key 10 is less than the threshold value, a response signal is transmitted only to the second request signal Srs2 transmitted into the vehicle. That is, when the battery voltage is less than the threshold value, a response signal is prevented from being transmitted in response to the first request signal Srs1 transmitted outside the vehicle. Therefore, when the battery voltage of the electronic key 10 is lowered, communication related to unlocking the vehicle door is executed, so that the power of the battery is consumed and the engine cannot be started. Thereby, it can suppress requesting the user to start the engine through transponder verification. This transponder verification method is more likely not to be recognized by the user than to lock and unlock the vehicle door through the mechanical key 17. For this reason, it is beneficial to suppress transponder verification.

  (2) If the vehicle door cannot be locked and unlocked through the electronic key 10 due to a decrease in the battery voltage of the electronic key 10, the mechanical key 17 is taken out from the main body of the electronic key 10. At this time, the battery is charged with power through the power generation device 18. This charged electric power is used not for communication related to locking / unlocking of the vehicle door but for communication related to engine startup. Therefore, the engine can be started through the normal electronic key 10.

  (3) In the state where the battery voltage of the electronic key 10 is lowered, the response signal is transmitted in response to the first request signal Srs1 from another vehicle, and the power consumption of the battery unit 15 is reduced.

(Second Embodiment)
Hereinafter, a second embodiment of the present invention will be described. In the electronic key system of this embodiment, the transmission timing of the second request signal Srs2 is different from that of the first embodiment. Hereinafter, a description will be given focusing on differences from the first embodiment. Note that the electronic key system of this embodiment has the same configuration as the electronic key system of the first embodiment shown in FIG.

  When the vehicle-mounted control unit 21 recognizes that the vehicle door is opened and closed through the courtesy switch 37 after unlocking the vehicle door, the vehicle-mounted control unit 21 transmits the first request signal Srs1 unlike the first embodiment. Further, when the in-vehicle control unit 21 recognizes that the engine switch 33 has been operated in a state where the vehicle interior verification is not established, the in-vehicle control unit 21 transmits a second request signal Srs2. On the other hand, the vehicle-mounted control unit 21 starts the engine when it recognizes that the engine switch 33 has been operated in a state where the vehicle interior verification has been established. The electronic key control unit 11 performs the same processing as in the first embodiment.

  Next, processing procedures of the in-vehicle control unit 21 and the electronic key control unit 11 will be described with reference to the flowchart of FIG. Note that the battery voltage of the battery unit 15 in the electronic key 10 of this example is less than the threshold value. In this flowchart, steps S201 to S204 are the same processes as steps S101 to S104 in FIG. 3 in the first embodiment. Therefore, the description here is omitted.

  When the vehicle-mounted control unit 21 recognizes that the vehicle door has been opened and closed through the courtesy switch 37, the vehicle-mounted control unit 21 transmits the first request signal Srs1 (S205). When receiving the first request signal Srs1, the electronic key control unit 11 determines that the battery voltage of the battery unit 15 is less than the threshold (S206), and does not transmit a response signal.

  When the in-vehicle control unit 21 recognizes that the engine switch 33 has been operated in a state where the vehicle interior verification is not established (S207), it transmits a second request signal Srs2 (S208). Upon receiving the second request signal Srs2, the electronic key control unit 11 transmits a response signal (S209). When the in-vehicle control unit 21 determines that the ID code included in the received response signal matches the ID code stored in the memory 21a (S210), it starts the engine (S211). This ends the flowchart.

As described above, according to the embodiment described above, the following effects can be obtained in addition to the effects of the first embodiment.
(4) The second request signal Srs2 is transmitted only when the engine switch 33 is operated. Accordingly, the transmission of the response signal in the vehicle compartment before the engine switch 33 is operated suppresses the battery voltage from decreasing to the extent that the response signal cannot be transmitted at the actual engine start. Therefore, even when the battery voltage of the electronic key 10 decreases, the engine can be started more reliably.

In addition, the said embodiment can be implemented with the following forms which changed this suitably.
In the first embodiment, the first request signal Srs1 is transmitted outside the vehicle and the second request signal Srs2 is transmitted inside the vehicle. However, both request signals Srs1 and Srs2 are transmitted outside or inside the vehicle. Also good. For example, the first request signal Srs1 is transmitted outside the vehicle when the lock switch 36 is operated once, and the second request signal Srs2 is also transmitted outside the vehicle when the lock switch 36 is operated continuously a plurality of times. It is good also as a structure to be. In this configuration, when the battery voltage of the electronic key 10 is lowered, the response signal is transmitted only when the user operates the lock switch 36 a plurality of times continuously. Therefore, unlike the first and second embodiments, even when the battery voltage of the electronic key 10 is low, the vehicle door can be opened through wireless communication by operating the lock switch 36 a plurality of times. Lock is possible. In addition, in a state where the battery voltage of the electronic key 10 is lowered, the response signal is transmitted in response to the first request signal Srs1 from another vehicle, and thus the power consumption of the battery unit 15 is reduced.

  Alternatively, the second request signal Srs2 may be transmitted from the outside transmission unit 22 corresponding to the vehicle door on the driver's seat side, and the first request signal Srs1 may be transmitted from the outside transmission unit 22 corresponding to another vehicle door. . In this case, in a state where the battery voltage of the electronic key 10 is lowered, if the user approaches the other vehicle door without intention of unlocking the vehicle door, a response signal is not returned. Therefore, power consumption related to the transmission of the response signal is suppressed. Similarly to the above, when the engine switch 33 is operated once, the first request signal Srs1 is transmitted into the vehicle, and when the engine switch 33 is operated continuously a plurality of times, the second request signal Srs2 is transmitted into the vehicle. May be configured to be transmitted.

  Further, the first request signal Srs1 and the second request signal Srs2 may be alternately transmitted every time the lock switch 36 or the engine switch 33 is operated or at a certain period. Even in this case, in the state where the battery voltage of the electronic key 10 is lowered, the number of times of transmission of the response signal in the electronic key 10 and thus the power consumption of the battery unit 15 can be reduced. The first request signal Srs1 and the second request signal Srs2 are not limited to each other as described above. For example, after the first request signal Srs1 is transmitted twice, the second request signal Srs2 is transmitted. May be transmitted once.

  In the second embodiment, the second request signal Srs2 is transmitted when it is recognized that the engine switch 33 is operated in a state where the vehicle interior verification is not established. However, the second request signal Srs2 may be transmitted when it is recognized that the engine switch 33 has been operated regardless of the result of the vehicle interior verification.

In each of the above embodiments, the power generation device 18 generates power by inserting and removing the mechanical key 17, but may generate power through light, heat, or vibration, for example. in this case,
Light energy, heat energy, and vibration energy become external energy. It is conceivable to use a solar cell when generating power through light, using a piezoelectric element when generating power through vibration, and using a thermoelectric exchange element when generating power through heat. Moreover, you may combine said each electric power generating apparatus. Further, the power generation device 18 may be omitted. In this case, a primary battery is used.

  In each of the above embodiments, when the vehicle door is in the locked state, the first request signal Srs1 is transmitted at regular intervals. However, the first request signal Srs1 may be transmitted when the lock switch 36 is operated. Also in this configuration, when the battery voltage is low, no response signal is returned to the first request signal Srs1.

  In each of the above embodiments, the outside transmission antenna 22a and the inside transmission antenna 23a are provided, but a configuration including a common antenna inside and outside the vehicle may be used. In this case, the antenna is provided in the vehicle. For example, when applied to the first embodiment, the second request signal Srs2 is transmitted from the antenna into the vehicle, and the first request signal Srs1 is transmitted to a range including the outside of the vehicle.

  -You may abbreviate | omit the transponder 14 and the immobilizer communication apparatus 25 in said each embodiment.

  DESCRIPTION OF SYMBOLS 1 ... Electronic key system, 2 ... Vehicle, 10 ... Electronic key, 11 ... Electronic key control part, 14 ... Transponder, 15 ... Battery unit, 15a ... Voltage sensor (battery voltage detection means), 17 ... Mechanical key, 18 ... Electric power generation Device: 20 ... In-vehicle device, 21 ... In-vehicle controller, 25 ... Immobilizer communication device.

Claims (5)

An in-vehicle device that transmits a request signal inside and outside the vehicle,
An electronic key that transmits a response signal including an ID code when the request signal is received, and when the vehicle-mounted device confirms the validity of the received response signal, the vehicle door is switched or unlocked or the engine is switched In the electronic key system that permits the start of
The electronic key includes battery voltage detection means for detecting a voltage of a battery in which electric power related to reception of the request signal and transmission of the response signal is stored,
The in-vehicle device transmits a first request signal or a second request signal as the request signal,
When the electronic key determines that the battery voltage is greater than or equal to a threshold value through the battery voltage detection means, the electronic key transmits the response signal upon receiving the first request signal or the second request signal, and the battery voltage If it is determined through the detection means that the battery voltage is less than the threshold, the response signal is transmitted only when the second request signal is received ,
The in-vehicle device transmits the first request signal to the outside of the vehicle, transmits the second request signal to the inside of the vehicle, and confirms the validity of the response signal with respect to the first request signal. An electronic key system that permits a lock and permits the engine to start when the validity of the response signal with respect to the second request signal is confirmed . The electronic key system according to claim 1 .
An electronic key system including a power generation device that generates power using energy applied from outside and charges the generated power to the battery. The electronic key system according to claim 2 .
A mechanical key that is removably stored in the main body of the electronic key and mechanically capable of switching the unlocking state of the vehicle door;
The power generation device is an electronic key system that generates power using energy generated when the mechanical key is taken out. The electronic key system according to any one of claims 1 to 3 ,
Provided with an engine switch that can be operated by the user near the driver's seat,
When the in-vehicle device recognizes that the engine switch has been operated, it transmits the second request signal into the vehicle, and permits the engine to start when the validity of the response signal with respect to the second request signal is confirmed. Electronic key system to do.   An in-vehicle device that transmits a request signal inside and outside the vehicle,
  An electronic key that transmits a response signal including an ID code when the request signal is received, and when the vehicle-mounted device confirms the validity of the received response signal, the vehicle door is switched or unlocked or the engine is switched In the electronic key system that permits the start of
  The electronic key includes battery voltage detection means for detecting a voltage of a battery in which electric power related to reception of the request signal and transmission of the response signal is stored,
  The in-vehicle device transmits a first request signal or a second request signal as the request signal,
  When the electronic key determines that the battery voltage is greater than or equal to a threshold value through the battery voltage detection means, the electronic key transmits the response signal upon receiving the first request signal or the second request signal, and the battery voltage If it is determined through the detection means that the battery voltage is less than the threshold, the response signal is transmitted only when the second request signal is received,
  In addition, a power generation device that generates power using externally applied energy and charges the battery with generated power,
  And a mechanical key that is removably stored in the main body of the electronic key and can be mechanically switched between a locked state and an unlocked state of the vehicle door,
  The power generation device is an electronic key system that generates power using energy generated when the mechanical key is taken out.

Images