JP2006063571A - Electronic key system for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a person to make a wrong judgment that an electronic key positioned outside a cabin is positioned inside the cabin. <P>SOLUTION: This system transmits a request signal from an in-cabin antenna 1, and determines that the electronic key 10 is positioned in the cabin, when a response signal is issued from the electronic key 10. While the antenna 1 transmits the request signal, jamming electric waves for jamming the request signal are emitted by means of out-of-cabin antennae 2a and 2b installed near a door handle provided outside a door. Thus, the electric key 10 positioned outside the cabin cannot receive the request signal transmitted from the antenna 1. Thus, the wrong judgment that the electric key is positioned outside the cabin is positioned inside the cabin is prevented. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a vehicular electronic key device that transmits a signal from an antenna provided in a vehicle interior and determines whether or not the electronic key exists in the vehicle interior based on a reply from a wireless electronic key.

  2. Description of the Related Art Conventionally, a keyless entry device that locks and unlocks a door of a vehicle by performing wireless communication between a wireless portable device and a vehicle-side wireless device is known. In this keyless entry device, in order to prevent the portable device from being left in the passenger compartment when the occupant gets off, the portable device transmits a signal from an antenna provided in the passenger compartment, and based on a reply from the portable device, There is known an apparatus for determining whether or not a vehicle is present in a passenger compartment (see Patent Document 1).

JP-A-60-164572

  However, in the conventional apparatus, when the signal output of the vehicle interior antenna is increased in order to improve the detection accuracy of the portable device existing in the vehicle interior, the radio wave (signal) emitted from the vehicle interior antenna leaks outside the vehicle interior, A portable device outside the vehicle interior may receive this radio wave and respond to the vehicle interior antenna. In this case, there arises a problem that it is erroneously determined that the portable device exists inside the vehicle compartment even though the portable device exists outside the vehicle compartment.

  In the electronic key device for a vehicle according to the present invention, after the first signal is transmitted from the vehicle interior signal transmitting / receiving means, a second signal which is a response signal to the first signal is transmitted from the electronic key to transmit / receive the vehicle interior signal. A device for determining that the electronic key is present in the passenger compartment when received by the means, and for disturbing the first signal while the vehicle interior signal transmitting / receiving means is transmitting the first signal. A signal is transmitted outside the passenger compartment.

  According to the vehicle electronic key device of the present invention, while the vehicle interior signal transmission / reception means transmits the first signal, the interference signal for interfering with the first signal is transmitted outside the vehicle interior. Even when the first signal transmitted from the indoor signal transmitting / receiving means leaks outside the vehicle compartment, the electronic key existing outside the vehicle interior receives the first signal and transmits the second signal to the vehicle interior signal transmitting / receiving means. Can be prevented.

  FIG. 1 is a diagram showing a configuration of an embodiment of an electronic key device for a vehicle according to the present invention. The vehicle electronic key device in one embodiment includes a vehicle interior antenna 1, vehicle exterior antennas 2a and 2b, a control device 3, a door lock actuator 4, and request switches 5a and 5b.

  The electronic key 10 does not have a key plate such as an ignition key, and is formed in, for example, a card shape so that a passenger can easily carry it. The electronic key 10 can communicate with the vehicle interior antenna 1 and the vehicle exterior antennas 2a and 2b via radio.

  FIG. 2 is a diagram showing the installation positions of the vehicle interior antenna 1 and the vehicle exterior antennas 2a and 2b. The vehicle interior antenna 1 is installed almost at the center of the vehicle interior. The vehicle exterior antenna 2a is provided near the door handle outside the driver's seat, and communicates with the electronic key 10 existing near the door outside the driver's seat. The vehicle exterior antenna 2b is provided near the door handle outside the passenger seat, and communicates with the electronic key 10 existing near the door outside the passenger seat. Here, a door iron plate is interposed between the vehicle interior antenna 1 and the vehicle exterior antenna 2a, and between the vehicle interior antenna 1 and the vehicle exterior antenna 2b, and the vehicle interior antenna 1 and the vehicle door. The vehicle interior antenna 1 and the vehicle exterior antennas 2a and 2b are arranged so that the distance between the vehicle interior antenna 2a and 2b is longer than the distance between the vehicle interior antennas 2a and 2b and the vehicle door. As described above, since the vehicle interior antennas 2a and 2b are provided near the door handle, the vehicle interior antenna 1 may be disposed at a position near the center console in the vehicle, for example.

  The request switch 5a is provided near the door handle outside the driver's seat, and the request switch 5b is provided near the door handle outside the passenger seat. When the request switch 5a or 5b is pushed by the occupant, a request signal for requesting a unique ID for the electronic key 10 is transmitted from the vehicle interior antenna 1. When the electronic key 10 is present in the vehicle interior and receives a request signal transmitted from the vehicle interior antenna 1, the electronic key 10 transmits an ID signal including the ID of the electronic key 10 to the vehicle interior antenna 1. . When receiving the ID of the electronic key 10 via the vehicle interior antenna 1, the control device 3 performs ID verification. If the ID verification result is OK, the control device 3 determines that the electronic key 10 exists in the vehicle interior.

  On the other hand, when the electronic key 10 is not present in the passenger compartment and the ID signal is not transmitted to the control device 3, and the control device 3 receives the ID signal, the result of the ID verification is NG. In this case, it is determined that the electronic key 10 does not exist in the vehicle interior, and a request signal requesting the ID of the electronic key 10 is transmitted from the vehicle exterior antennas 2a and 2b.

  When the electronic key 10 exists outside the vehicle interior and receives a request signal transmitted from the vehicle exterior antennas 2a and 2b, the electronic key 10 receives an ID including the ID of the electronic key 10 with respect to the vehicle exterior antennas 2a and 2b. Send a signal. When the control device 3 receives the ID of the electronic key 10 via the antenna 2a or 2b outside the vehicle compartment, the control device 3 performs ID verification. If the ID verification result is OK, the door lock actuator 4 is operated to activate the door of the vehicle. Lock or unlock That is, when the door is locked, the unlocking process is performed, and when the door is unlocked, the locking process is performed.

  FIG. 3 is a diagram illustrating an example of the magnetic field strength of the radio wave (request signal) transmitted from the vehicle interior antenna 1 and the magnetic field strength of the radio wave transmitted from the vehicle interior antennas 2a and 2b. In the vehicle electronic key device according to the embodiment, the output of the radio wave transmitted from the vehicle interior antenna 1 is increased in order to increase the detection accuracy of the electronic key 10 present in the vehicle interior. In this case, as shown in FIG. 3, the radio wave emitted from the vehicle interior antenna 1 leaks outside the vehicle interior, but since the vehicle door is interposed, the intensity of the radio wave of the vehicle interior antenna 1 leaking out of the vehicle interior is as follows. Reduced. Similarly, it is possible to reduce the strength of the radio waves of the vehicle interior antennas 2a and 2b in the vehicle interior.

  As described above, the strength of the radio wave of the vehicle interior antenna 1 leaking out of the passenger compartment is reduced by the presence of the vehicle door. However, as shown in FIG. Leak outside. In this case, when the request signal is transmitted from the vehicle interior antenna 1, the electronic key 10 existing outside the vehicle interior receives the request signal and transmits the ID signal to the vehicle interior antenna 1, so that the electronic key 10 exists in the vehicle interior. Then, it may be misjudged. Therefore, in the vehicle electronic key device according to the embodiment, while the request signal is transmitted from the vehicle interior antenna 1, the interference radio wave for interfering with the radio wave of the vehicle interior antenna 1 from the vehicle interior antennas 2a and 2b. To send. Thereby, the request signal transmitted from the vehicle interior antenna 1 is prevented from being received by the electronic key 10 existing outside the vehicle interior.

  FIG. 4 is a flowchart showing the contents of processing performed by the vehicle electronic key device according to the embodiment. When the vehicle is activated, the control device 3 starts the process of step S10. In step S10, it is determined whether the request switch 5a or 5b has been pressed by the occupant. If it is determined that the request switch 5a or 5b is not operated, the process waits in step S10. If it is determined that the request switch 5a or 5b is operated, the process proceeds to step S20.

  In step S20, a request signal is transmitted from the vehicle interior antenna 1 and the above-described jamming radio waves are transmitted from the vehicle interior antennas 2a and 2b. In step S30 following step S20, an ID signal is received from the electronic key 10 via the vehicle interior antenna 1, and it is determined whether or not the ID collation result is OK. If an ID signal is received from the electronic key 10 via the vehicle interior antenna 1 and it is determined that the ID verification result is OK, the process proceeds to step S70, and it is determined that the electronic key 10 is present in the vehicle interior. On the other hand, when the ID signal cannot be received or when the ID signal is received but the ID collation result is NG, it is determined that the electronic key 10 does not exist in the passenger compartment, and the process proceeds to step S40.

  In step S40, request signals are transmitted from the vehicle interior antennas 2a and 2b, and the process proceeds to step S50. In step S50, an ID signal is received from the electronic key 10 via the vehicle exterior antenna 2a or 2b, and it is determined whether or not the ID collation result is OK. If the ID signal is received from the electronic key 10 via the outside antenna 2a or 2b and it is determined that the ID verification result is OK, the process proceeds to step S60, and if the ID signal cannot be received, or the ID If the signal is received but the ID collation result is NG, the process of the flowchart shown in FIG. 4 is terminated.

  In step S60, the door is locked or unlocked. That is, when the door is locked, the door unlocking process is performed, and when the door is unlocked, the door locking process is performed. When the door lock or unlock process is performed, the process of the flowchart shown in FIG. 4 ends.

  According to the vehicle electronic key device in one embodiment, when a request signal is transmitted from the vehicle interior antenna 1 and a reply is received from the electronic key 10, it is determined that the electronic key 10 is present in the vehicle interior. While the request signal is transmitted from the vehicle interior antenna 1, an interference wave for interfering with the request signal is transmitted from the vehicle interior antennas 2a and 2b, so that the electronic key 10 existing outside the vehicle interior is connected to the vehicle. The request signal transmitted from the indoor antenna 1 can be received and prevented from responding. That is, it can be prevented that the electronic key 10 existing outside the passenger compartment is erroneously determined as being present in the passenger compartment. Thereby, the signal output of the vehicle interior antenna 1 can be strengthened and the detection accuracy of the electronic key 10 existing in the vehicle interior can be increased.

  According to the vehicle electronic key device in one embodiment, it is possible to increase the signal output of the vehicle interior antenna 1 while preventing the electronic key 10 existing outside the vehicle interior from being erroneously determined to be present in the vehicle interior. Therefore, it is not necessary to provide a plurality of vehicle interior antennas in order to increase the detection accuracy of the electronic key 10 existing in the vehicle interior. Thereby, cost can be held down.

  In addition, since the antennas 1, 2a, 2b are arranged on the straight line connecting the vehicle interior antenna 1 and the vehicle exterior antennas 2a, 2b so that an electromagnetic shielding metal member such as a vehicle door is interposed, It is possible to reduce the amount of disturbing waves transmitted from the vehicle interior antennas 2a and 2b entering the vehicle interior. Accordingly, it is possible to prevent the request signal transmitted from the vehicle interior antenna 1 from being received by the electronic key 10 existing in the vehicle interior due to the influence of the interference wave. This is particularly effective for an LF band frequency signal that does not reflect electromagnetic waves and is difficult to control the directivity of radio waves.

  In addition, according to the electronic key device for a vehicle in the embodiment, in the keyless entry system, generally, the jamming radio wave is transmitted from the antenna outside the vehicle compartment provided near the outer door handle. There is no need to provide a separate antenna for transmitting the signal, and the cost can be reduced compared to the case where a separate antenna for transmitting the jamming radio wave is provided.

  The present invention is not limited to the embodiment described above. For example, while transmitting the request signal from the vehicle interior antenna 1, the vehicle exterior antennas 2a and 2b that are generally used in the keyless entry system are used as antennas that transmit jamming radio waves outside the vehicle interior. Aside from the vehicle interior antennas 2a and 2b, an antenna for transmitting a disturbing wave may be installed. FIG. 5 is a diagram showing an example of an installation position when the interference wave transmitting antennas 7a and 7b are installed separately from the vehicle exterior antennas 2a and 2b.

  In the above description, when the request switch 5a or 5b is pressed, the process of determining whether or not the electronic key 10 exists in the vehicle interior is started. However, this determination process can be performed at an arbitrary timing. In addition, a request signal is transmitted from the vehicle interior antenna 1, an ID signal is received from the electronic key 10, and if the result of the ID verification is OK, it is determined that the electronic key 10 exists in the vehicle interior. If there is a response from the electronic key 10 after transmitting the request signal without performing ID verification, it may be determined that the electronic key 10 exists in the passenger compartment.

  The present invention is limited by the type of signal transmitted and received between the electronic key 10 and the vehicle interior antenna 1 and the vehicle interior antennas 2a and 2b, the installation location of the vehicle interior antenna 1 and the vehicle interior antennas 2a and 2b, and the like. It will never be done.

  The correspondence between the constituent elements of the claims and the constituent elements of the embodiment is as follows. That is, the vehicle interior antenna 1 constitutes vehicle interior signal transmission / reception means, the vehicle interior antennas 2a, 2b or the interference wave transmission antennas 7a, 7b constitute interference signal transmission means, and the control device 3 constitutes determination means. In addition, as long as the characteristic function of this invention is not impaired, each component is not limited to the said structure.

The figure which shows the structure in one Embodiment of the electronic key device for vehicles by this invention. The figure which shows the installation position of the vehicle interior antenna and the vehicle exterior antenna The figure which shows an example of the magnetic field intensity of the electromagnetic wave transmitted from a vehicle interior antenna, and the magnetic field strength of the electromagnetic wave transmitted from an antenna outside a vehicle interior The flowchart which shows the processing content performed with the electronic key device for vehicles in one embodiment The figure which shows an example of the installation position of the antenna at the time of providing the interference wave transmission antenna separately from the vehicle interior antenna

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Vehicle interior antenna, 2a, 2b ... Vehicle exterior antenna, 3 ... Control apparatus, 4 ... Door lock actuator, 5a, 5b ... Request switch, 7a, 7b ... Interference wave transmission antenna, 10 ... Electronic key

Claims (5)

Vehicle interior signal transmitting / receiving means that is provided in the vehicle interior and communicates wirelessly with the electronic key;
After the first signal is transmitted by the vehicle interior signal transmission / reception means, a second signal that is a reply signal to the first signal is transmitted from the electronic key and received by the vehicle interior signal transmission / reception means. Determining means for determining that the electronic key is present in the passenger compartment;
An interference signal transmitting means that is provided outside the passenger compartment and that transmits an interference signal for interfering with the first signal while the vehicle interior signal transmitting / receiving means transmits the first signal. An electronic key device for a vehicle. The electronic key device for a vehicle according to claim 1,
The vehicle interior signal transmission / reception means and the interference signal transmission means are arranged so that a member having an electromagnetic shielding property is interposed on a straight line connecting the vehicle interior signal transmission / reception means and the interference signal transmission means. An electronic key device for a vehicle. The vehicle electronic key device according to claim 2,
The vehicle interior signal transmission / reception is performed such that a distance between the vehicle interior signal transmission / reception means and the electromagnetic shielding member is longer than a distance between the interference signal transmission means and the electromagnetic shielding member. An electronic key device for a vehicle, characterized in that a means and the interference signal transmission means are arranged. The vehicle electronic key device according to claim 2 or 3,
The electronic key device for vehicles, wherein the electromagnetic shielding member is a vehicle door. The vehicle electronic key device according to any one of claims 1 to 4,
The vehicle electronic key device according to claim 1, wherein the interference signal transmitting means is an antenna outside the vehicle compartment that communicates with the electronic key when the vehicle door is locked / unlocked.

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