JP4638814B2 - Communication device - Google Patents

Description

  The present invention is a communication that includes, in a device or facility, a signal generation unit that generates a transmission signal for a portable receiver owned by a user, and a transmission antenna unit that is connected to the signal generation unit and transmits the transmission signal. Relates to the device.

  Even if the vehicle occupant does not use the key to unlock and lock, the vehicle door lock can be unlocked and locked automatically only by approaching the vehicle and leaving the vehicle. There is a smart entry system (keyless entry system) as is done. Such a smart entry system communicates between a communication device mounted in a vehicle and a portable transceiver carried by a vehicle occupant using a long wave (134 kHz) transmission radio wave. By authenticating the transceiver, this system provides a control that automatically unlocks the door of the vehicle when an occupant approaches the vehicle and automatically locks when the passenger leaves the vehicle. Therefore, a communication device provided on the vehicle side includes a signal generation unit that generates a transmission signal for a portable transceiver that is held by a passenger, and a transmission antenna unit that is connected to the signal generation unit and transmits the transmission signal. Is installed. Recently, the number of vehicles equipped with such a system is increasing, and it is expected that further spread will be promoted in the future.

  A long-wave band frequency is used to transmit a transmission signal from a communication device mounted in a vehicle to a portable transceiver held by an occupant, and the transmission antenna unit is a bar in which a coil is wound around a magnetic material such as ferrite. An antenna is used. A bar antenna is incorporated in a vehicle door handle or the like and applies a magnetic field within a few meters of the bar antenna. As a result, the transmission signal is transmitted to a portable transceiver carried by a passenger approaching the vehicle (for example, a patent) Reference 1).

  In addition, a system that employs a loop antenna configured by arranging conductive wires in a loop shape inside the door body as a transmission antenna unit having a configuration replacing the above-described bar antenna is also conceivable. In addition, it is not preferable to arrange a loop-shaped conductor on the surface of the vehicle body or the door body as a transmission antenna part due to design restrictions.

JP 2000-160897 A

In the antenna used in the system or the like described in Patent Document 1 above, the coil placed inside the bar antenna or the door is placed on the surface of the automobile body or inside the door, so the eddy current loss increases, and these The antenna efficiency is significantly lower than when the antenna is used in free space.
Further, in the case of a system that employs a loop antenna configured by arranging conductive wires in a loop shape inside the door body, at least a part of the above-described loop antenna is shielded by the conductive door body. Therefore, the transmission power is forced to increase in order to increase the intensity of the radiated radio wave from the transmission antenna unit to the portable transceiver. In the smart entry system as described above, it is necessary to constantly transmit transmission signals at regular intervals while the vehicle is stopped from the communication device. Therefore, in order to reduce the burden on the battery, it is preferable that the transmission signal can be transmitted with as little power consumption as possible.
Furthermore, the bar antenna incorporated in the handle has a problem in that the door handle material is limited to the resin member because the magnetic field is shielded when the door handle is made of a metal member. In addition, in future automobiles, there is a possibility that the door handle itself may be lost, and in this case, it is desired to develop an antenna having a configuration replacing the bar antenna.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a communication apparatus that includes a transmission antenna unit having a configuration different from the conventional one and can realize communication with less power.

  In order to achieve the above object, a first characteristic configuration of a communication device according to the present invention includes: a signal generation unit that generates a transmission signal for a portable receiver owned by a user in a device or facility; and the signal generation unit A transmission antenna unit that is connected to the transmission antenna and transmits the transmission signal, and as the transmission antenna unit, a signal current can be passed through a loop path formed using a conductive member that constitutes the device or the facility This is in the use of a loop antenna.

Like this structure, a large loop area can be ensured by making the loop-shaped path | route using the electroconductive member which comprises the said apparatus or the said facility into a loop antenna. Therefore, as a result of energizing the signal current here, the antenna efficiency can be dramatically improved.
In addition, with this configuration, the configuration is simpler than a conventional door handle provided with a ferrite bar or the like, and the reliability with respect to failure is improved.
Furthermore, when the transmission antenna unit is configured, the number of parts is reduced and the assembly process is simplified, so that the effect of cost reduction is great.
In addition, it is not necessary to mount the antenna on the surface of the vehicle body, and it does not impose any restrictions on the vehicle design.

  According to a second characteristic configuration of the communication device according to the present invention, the conductive member is formed in an annular shape, and the first part and the second part that connect the output terminal of the signal generation unit are connected to the conductive member. It exists in the point which provided in two different places and comprised the said signal generation part and the said electroconductive member in parallel.

  As in this configuration, since it is only necessary to connect the output terminal of the signal generation unit to any two of the conductive members, the loop antenna can be configured very simply.

  According to a third characteristic configuration of the communication device according to the present invention, the conductive member is formed in a substantially annular shape through an electrical insulating portion in the middle, and the first portion connecting the output terminal of the signal generating portion and the first portion Two portions are provided at both ends of the conductive member, respectively, and the signal generation unit and the conductive member are configured in series.

  If the signal generation unit and the conductive member are configured in series as in this configuration, for example, a section where the power supply line of the signal generation unit and the conductive member are arranged in parallel can be eliminated. Therefore, a current flows in the opposite direction to the power supply line and the conductive member and the radiated radio wave intensity is not reduced, and a communication device with high power supply efficiency can be obtained.

  According to a fourth characteristic configuration of the communication device according to the present invention, the conductive member is a vehicle body of the vehicle as the device, and an opening / closing body provided with one output terminal of the signal generation unit at an opening of the vehicle body. It connects to a catch part, and is in the point which connected another output terminal to the support part which connects the said opening-closing body to the said vehicle body.

  If it is this structure, the edge part of the opening in which an opening-and-closing body is provided in a vehicle turns into a loop-shaped path | route through which an electric current flows. Therefore, the directivity of the transmission antenna unit can be directed to the direction of the portable receiver possessed by the user close to the opening / closing body, and the transmission signal generated by the signal generation unit can be reliably transmitted.

  According to a fifth characteristic configuration of the communication device according to the present invention, the conductive member is a vehicle body of the vehicle as the device, and the electrical insulating portion is a catch portion of an opening / closing body provided in an opening of the vehicle body or the The opening / closing body is arranged at a support portion connected to the vehicle body.

Since the vehicle body is usually made of a steel plate, it is surprisingly troublesome to provide the electrical insulating portion at any point as described above. However, since the catch part and the support part are attached to the vehicle body later, it is very easy to provide the electrical insulation part at these places.
By providing the electrical insulating portion in this way, it is possible to obtain a high-performance communication device with a simple configuration but with improved power feeding efficiency.

  In the sixth characteristic configuration of the communication apparatus according to the present invention, the output of the transmission signal from the signal generation unit can be fed to the loop antenna by magnetic field coupling with the loop path.

  If the transmission signal is directly fed to the loop antenna, it is predicted that the input resistance of the conductive member constituting the loop antenna varies, and matching of the device on the transmitter side becomes a problem. However, as long as power is supplied by magnetic field coupling as in this configuration, the power supply state of the transmission signal to the device that generates the magnetic field can be set in advance, so that there is no problem of matching of the devices, and an optimal power supply state is obtained. be able to.

  According to a seventh characteristic configuration of the communication device according to the present invention, the conductive member is a vehicle body of the vehicle as the device, and the power feeding by the magnetic field coupling is performed by a catch portion of an opening / closing body provided in an opening of the vehicle body or The opening / closing body is formed by a magnetic body disposed on a support portion connected to the vehicle body.

The catch portion or the support portion constitutes a so-called bridge that connects the vehicle body and the opening / closing body of the vehicle. If it is such a site | part, it is convenient to install the said magnetic body, and it is also easy to supply the feeding current formed with the magnetic body to the opening / closing body. In this case, there is no need to apply special processing to the catch portion or the support portion, or to reconfigure them with a special material, and there is no inconvenience of impairing the strength of the catch portion or the support portion.
With this configuration, not only the opening of the vehicle body is used as a loop antenna, but also the function of the opening / closing body as a loop antenna can be improved by supplying power efficiently to the opening / closing body. An efficient communication device can be obtained.

  An eighth characteristic configuration of the communication apparatus according to the present invention is that the conductive member is a vehicle body as the device.

  If it is the vehicle body of a vehicle, the loop-shaped path | route which can be used as the said electroconductive member can be set to various places. For example, in addition to the opening / closing body provided on the vehicle body, the edge of the opening of the front window, the edge of the window opening of the front seat / rear seat side door, the opening of the filler opening, etc. are used as the loop path. Can do. Therefore, not only as a communication device related to passenger getting on and off, but also a communication device for various uses such as opening / closing control of a window part, a fuel filler opening, etc. can be configured.

<First Embodiment>
The configuration of a communication apparatus according to the present invention will be described below with reference to the drawings.
A communication apparatus according to the present invention includes a signal generation unit that generates a transmission signal for a portable receiver owned by a user in a device or facility, and a transmission antenna unit that is connected to the signal generation unit and transmits the transmission signal. Is provided. Usually, the portable receiver also has a transmission function for a communication device. In the following, the portable transceiver is simply referred to as a portable device.
The portable device can have a role of a key for using a device or a facility. In other words, the communication device communicates with the portable device to authenticate whether the portable device is valid, and permits the use of the device or facility only to the user who possesses the valid portable device. Such a system can be constructed. For example, devices that are permitted to be used only when the user has a legitimate portable device include vehicles such as automobiles and motorcycles, and information terminal devices such as computers. In addition, facilities that are permitted to be used only when the user has a legitimate portable device include buildings and rooms that are prohibited from entry by persons other than those involved.

Below, the case where the communication apparatus C which concerns on this invention is applied to the smart entry system 1 of a vehicle is demonstrated. As shown in FIG. 1, the smart entry system 1 includes a portable device 60 possessed by a user (for example, a vehicle occupant) and a vehicle-side device 2.
The vehicle side device 2 is provided with a communication device C that communicates with the portable device 60 and devices such as sensors and switches that detect user operations. And in the vehicle side apparatus 2, unlocking | locking / locking of the door of a vehicle is performed based on the communication result between the communication apparatus C and the portable device 60, and detection results, such as a sensor and a switch.

Examples of the vehicle-side device 2 include a device provided inside the vehicle compartment, a device provided outside the vehicle compartment, a switch operation detection unit 51 that detects switch operation such as ignition, and a door open / close detection unit 52 that detects opening and closing of the door. In addition, there is a sensor electrode group 53 that detects vehicle speed and opening / closing of windows by various sensor electrodes.
As a device provided in the vehicle interior of the door panel, a vehicle interior antenna 41 that performs communication within the vehicle, a vehicle interior driver 42 that is connected to the vehicle interior antenna 41, a tuner 43, and a system ECU 44 are provided. The vehicle interior antenna 41 is provided at a place where radio waves such as a center console in the vehicle compartment can radiate into the vehicle, and the system ECU 44 is connected to the vehicle interior driver 42 and the tuner 43. The tuner 43 is attached to an inner mirror in the vehicle.
The device provided outside the passenger compartment of the door panel includes an antenna 25 outside the passenger compartment that communicates with the outside of the vehicle, a door actuator 11 that unlocks and locks the door of the vehicle, and an electric control unit for the door that controls the operation of the door actuator 11. (ECU) 12 is provided. The door panel is provided with a driver 30 outside the passenger compartment. The vehicle handle 20 mounted on the outside of the door panel is provided with an unlocking operation sensor 22 and a locking operation switch 23 described later. The vehicle exterior driver 30 is connected to the vehicle exterior antenna 25, the unlocking operation sensor 22, and the locking operation switch 23.

As described above, the vehicle interior antenna 25 functions as the transmission antenna unit of the present invention.
Further, the system ECU 44, the vehicle exterior driver 30, and the vehicle exterior antenna 25 function as a communication device C for performing communication with the portable device 60. The vehicle interior driver 42, the vehicle interior antenna 41, and the tuner 43 may also be included in the communication device C for performing communication with the portable device 60.

  Below, the unlocking process / locking process of the vehicle door performed in the smart entry system 1 will be described in order. The smart entry system 1 authenticates the user by communicating between the communication device C mounted on the vehicle and the portable device 60 possessed by the user, and unlocks / locks the door based on the authentication result. The operation is executed.

Specifically, in the smart entry system 1, the door is unlocked / locked by the following procedure.
(1) Preparation for unlocking operation accompanying the proximity of the user in the locked state (preparation for unlocking)
When preparing for unlocking, it is determined that the portable device 60 such as a key or electronic card possessed by the user has approached the vehicle. In this determination, the communication device C transmits a vehicle exterior request signal (transmission signal) from the vehicle interior antenna 25.
(2) Unlocking when the user touches the handle (unlocking)
Unlocking is performed by detecting that the user has touched the vehicle handle 20, and unlocking is executed in accordance with this detection. Therefore, the capacity sensor as the unlocking operation sensor 22 provided in the vehicle handle 20 detects the contact state of the vehicle handle 20 by the user.
(3) Preparation for the locking operation accompanying the movement of the user outside the vehicle in the unlocked state (locking preparation)
(4) Locking when the user touches the vehicle handle 20 (locking execution)
Locking is performed by detecting that the user has touched the locking operation switch 23 and performing locking according to this detection.
Therefore, in the smart entry system 1, the user's contact operation and the like are detected from the approach / detachment of the user to the vehicle, and the door is locked / unlocked without operating the vehicle key. be able to.

Hereinafter, the configuration and operation of the smart entry system 1 will be described in detail.
FIG. 1 is a block diagram of the smart entry system 1, and FIG. 2 is a functional block diagram showing a connection relationship between the system ECU 44, the vehicle handle 20, the vehicle exterior driver 30, and the vehicle exterior antenna 25.

  The system ECU 44 of the vehicle-side device 2 sends request signals (external request signal and in-vehicle request signal) as transmission signals to the outside driver 30 and the in-vehicle driver 42, respectively. In the present embodiment, a request signal having a carrier frequency of 134 kHz is transmitted from the vehicle interior antenna 25 and the vehicle interior antenna 41 to the portable device 60 as a vehicle exterior request signal and an indoor request signal.

  Further, the tuner 43 receives the ID information signal output from the portable device 60 in response to the request signal. In the present embodiment, the ID information signal has a carrier frequency of 315 MHz. This signal is demodulated by the tuner 43 and input to the system ECU 44.

  The system ECU 44 has a function of storing a code such as a door unlocking / locking code, an engine starting code, and a transponder ID verification code in the memory 45 even when the power is shut off.

  The portable device 60 has a transmission antenna 62 and a reception antenna 64. The transmitting antenna 62 transmits an ID information signal to the vehicle at a carrier frequency of 315 MHz. The receiving antenna 64 receives an ID request signal with a carrier frequency of 134 kHz transmitted from the vehicle. The transmission antenna 62 and the reception antenna 64 are connected to a transmission / reception circuit 66 connected to the controller 68.

  A request signal (external request signal) from the vehicle received by the receiving antenna 64 of the portable device 60 is demodulated by the transmission / reception circuit 66 and input to the controller 68. The controller 68 transmits the code stored in the memory 69 to the transmission / reception circuit 66. This code includes ID information unique to the portable device 60, is modulated by the transmission / reception circuit 66, and is transmitted from the transmission antenna 62 to the vehicle tuner 43 as a signal having a carrier frequency of 315 MHz.

As shown in FIG. 2, the vehicle exterior driver 30 includes a detection unit driver 31 and a transmission amplifier 32. The vehicle exterior request signal output from the system ECU 44 is input to the terminal CLG, modulated and amplified by the transmission amplifier 32, transmitted to the antenna 25 outside the vehicle connected to the terminals ANT1 and ANT2, and transmitted outside the vehicle as radio waves. Is done.
That is, the system ECU 44 and the transmission amplifier 32 function as a signal generation unit of the present invention.

  A signal output from the system ECU 44 in the door unlocking detection mode and the door locking detection mode is input to the terminal SEL and activates the detection unit driver 31 connected to the terminal SEL. The detection unit driver 31 detects the locking operation switch 23 via the terminal SGT1, and detects the unlocking operation sensor 22 via the terminal SGT2. The vehicle exterior antenna 25, the unlocking operation sensor 22, the locking operation switch 23 and the above terminals are electrically connected by signal lines.

  The locking operation switch 23 is a push-in switch that is turned on while the user's pressing operation is being performed. The locking operation switch 23 is built in a specific portion that is pressed by the user's finger when locking on the front side of the vehicle handle 20. Can recognize the operation of the vehicle handle 20 when closing the door.

  The unlocking operation sensor 22 is a capacitance type sensor, and its electrode is built in the vehicle handle 20 to operate the vehicle handle 20 (contact with the vehicle handle 20) when the user opens the door. It can be recognized.

  In the present embodiment, the locking operation switch 23 is provided for the locking operation. However, as with the unlocking operation sensor, the user changes the capacitance when the user touches the vehicle handle 20. It is good also as an electrostatic capacitance type sensor which detects operation of handle 20 for vehicles by.

  When the user opens the door, the user's hand grips and pulls the vehicle handle 20, so the user's hand contacts the back side of the vehicle handle 20. Thereby, the unlocking operation sensor 22 detects the opening operation of the door by the handle operation of the user. The detection unit driver 31 detects a change in the signal from the terminal SGT2 at this time, and transmits a sense signal to the system ECU 44 via the terminal SENS.

When the user closes the door, the user's hand contacts the front side of the vehicle handle 20 and pushes the locking operation switch 23 provided there. Therefore, the locking operation switch 23 is operated by the user's handle operation. Detects the closing motion of.
The detection unit driver 31 detects a change in the signal from the terminal SGT1 at this time, and transmits a lock signal to the system ECU 44 via the terminal SENS.

When the vehicle is parked, a request signal is transmitted from the system ECU 44 to the driver 30 outside the vehicle interior, and a vehicle exterior request signal (134 kHz) is transmitted as a radio wave from the vehicle interior antenna 25 toward the outside of the vehicle at set time intervals.
When the user approaches the vehicle together with the portable device 60, the receiving antenna 64 of the portable device 60 receives the outside request signal from the vehicle, the controller 68 processes the outside request signal via the transmission / reception circuit 66, and the transmitting antenna 62 Transmits an ID information signal (315 MHz).
When the tuner 43 receives the ID information signal and transmits it to the system ECU 44, the system ECU 44 recognizes that the portable device 60 has approached the vehicle. When the system ECU 44 recognizes that the legitimate portable device 60 is approaching, the system ECU 44 shifts to the door unlocking mode in order to confirm the door opening operation by the user.

In the door unlocking mode, the system ECU 44 detects the unlocking operation of the user by the unlocking operation sensor 22 via the driver 30 outside the passenger compartment.
When the user grips the vehicle handle 20 from this state, a sense signal is transmitted from the unlocking operation sensor 22 to the system ECU 44 via the vehicle exterior driver 30. Then, the system ECU 44 processes the sense signal and transmits a door unlock signal to the door ECU 12. As a result, the door ECU 12 unlocks the door by the door actuator 11.

  When the user is in the vehicle, a request signal is transmitted from the system ECU 44 to the vehicle interior driver 42, and the request signal is transmitted as a radio wave from the vehicle interior antenna 41 toward the vehicle interior. When the portable device 60 is in the vehicle, the request signal from the vehicle interior antenna 41 is received by the portable device 60, and the ID information signal transmitted from the transmission antenna 62 is received by the tuner 43. If the user opens the door and goes outside the vehicle from this state, the portable device 60 cannot receive the in-vehicle request signal from the vehicle interior antenna 41.

  Therefore, the system ECU 44 recognizes that the transmission of the ID information signal from the portable device 60 in response to the in-vehicle request signal is interrupted, and the portable device 60 has moved out of the vehicle (out of the user). When the portable device 60 goes out of the vehicle and closes the door, the system ECU 44 shifts to the door locking mode.

In the door locking mode, the system ECU 44 detects the operation of the locking operation switch 23 by the user.
In this state, when the user touches the vehicle handle 20 and presses the locking operation switch 23, a lock signal is transmitted from the locking operation switch 23 to the system ECU 44 through the vehicle exterior driver 30. The system ECU 44 processes the lock signal, transmits a request signal to the vehicle exterior driver 30, and transmits the vehicle exterior request signal from the vehicle exterior antenna 25 to the outside of the vehicle as a radio wave.

  At this time, since the user is in the vicinity of the door outside the vehicle together with the portable device 60, an ID information signal is transmitted from the portable device 60 in accordance with the request signal outside the vehicle. On the vehicle side, the tuner 43 receives the ID information signal and transmits it to the system ECU 44. Thus, when it is confirmed that the user (portable device 60) is outside the vehicle, the system ECU 44 transmits a door locking signal to the door ECU 12, and the door ECU 12 locks the door by the door actuator 11.

Next, with reference to FIG.3 and FIG.4, the structure of the antenna 25 outside a vehicle interior as a transmission antenna part of this invention is demonstrated.
The vehicle exterior antenna 25 is connected to the transmission amplifier 32 that constitutes the signal generation unit of the present invention, and transmits a vehicle exterior request signal as a transmission signal. The vehicle interior antenna 25 acts when a signal current flows through a loop path formed by using a conductive member such as a vehicle body constituting the vehicle, a door as an opening / closing body provided in the vehicle body, and a window frame. It is a loop antenna. The current flowing through the loop path is a high-frequency current flowing while changing with time at the carrier frequency (134 kHz) of the above-described outside request signal. Therefore, since the loop radius is sufficiently smaller than the wavelength (about 2.237 km), this antenna can be regarded as a minute loop antenna.

  FIG. 3 is a diagram for explaining a loop path X (outdoor compartment antenna 25) on the vehicle body (conductive member) 70 of the vehicle through which the signal current output from the transmission amplifier 32 flows. As shown in FIG. 3, in the first embodiment, the output terminals (terminal ANT1 and terminal ANT2) of the transmission amplifier 32 are a first part and a second part provided at different positions along the loop path X. It is connected to the. Specifically, the above-described two output terminals, the terminal ANT1 and the terminal ANT2, are catch portions that hold a door (not shown) provided in the opening of the conductive vehicle body 70 that forms the side surface of the vehicle in a closed state. Are connected to a door catch portion 71 as a support portion and a door hinge portion 74 as a support portion that rotatably connects the vehicle body 70 and the door by a hinge mechanism 75. The door catch portion 71 and the door hinge portion 74 correspond to the first portion and the second portion in the present invention. Further, in the communication device of this configuration, the signal generation unit is connected in parallel to the conductive member that forms the loop path X.

  More specifically, the door catch portion 71 includes a striker 72 that is fixed to the vehicle body 70 with screws 73 and includes a latch mechanism (not shown) provided inside the door 80. The door hinge portion 74 has a hinge mechanism 75 fixed to the vehicle body 70 using screws 76. The terminals ANT1 and ANT2 are connected to the screws 73 and 76, respectively. As a result, the terminals ANT1 and ANT2 are electrically connected to the vehicle body 70. In this case, a loop-shaped current flows through the path X along the edge of the opening. As a result, this path X forms a minute loop antenna. In the loop of the path X, a magnetic field that penetrates the loop vertically is formed.

Since the loop antenna (path X) as the vehicle exterior antenna 25 is formed along the side surface of the vehicle, the vehicle exterior antenna 25 has antenna directivity along a direction perpendicular to the vehicle side surface. Therefore, as shown in FIG. 3, when the outside antenna 25 is provided along the edge of the opening of the door of the driver's seat, the antenna 25 outside the passenger's seat is provided to the user approaching the driver's seat. Good directivity. Therefore, a strong magnetic field can be selectively applied to the portable device of the user approaching the door on the driver's seat side, but for a portable device approaching the door on the rear seat side, for example, A strong magnetic field cannot be applied.
Also, since the magnetic field is shielded by the door on the passenger seat side outside the door on the passenger seat side along with the driver's seat, a strong magnetic field is not exerted on the portable transceiver close to the door on the passenger seat side. Can not.

FIG. 4 is a diagram schematically showing current paths x1 to x6 formed in the vehicle body 70 and the door 80, which are conductive members, when the vehicle door 80 is closed. As illustrated, current paths x1 and x3 through which a signal current from the transmission amplifier 32 flows are current paths between the striker 72 of the door catch portion 71 and the door hinge portion 74 on the vehicle body 70, and this loop-shaped route. A loop antenna is formed by the current paths x1 and x3.
When the vehicle door 80 is closed, the vehicle body 70 and the door 80 are electrically connected by the striker 72 and the latch mechanism (not shown) of the door catch portion 71, and the vehicle body 70 and the door 80 are electrically connected by the door hinge portion 74. is doing. As a result, the signal current from the transmission amplifier 32 flows on the door 80 via the door catch portion 71 and the door hinge portion 74. For example, FIG. 4 shows a current path x2 that flows through the upper part of the window frame of the door 80 and a current path x4, x5, and x6 that flows through the door panel portion below the window frame of the door 80.
In this way, when the vehicle door 80 is closed, the vehicle body 70 and the door 80 are formed with a loop path X (x1 to x6, etc.) indicated by arrows in FIG. An antenna 25 is realized. Conductive wires 81 and 82 connected from the transmission amplifier 32 to the door catch portion 71 and the door hinge portion 74 also function as loop antennas.

FIG. 5 is a schematic circuit diagram of the transmission amplifier 32 as the signal generation unit shown in FIG. As shown in FIG. 5, the vehicle exterior request signal output from the system ECU 44 is input to the transmission amplifier 32 via the terminal CLG. This request signal outside the vehicle is amplified and modulated in the voltage amplifying unit 33. Thereafter, the modulated request signal outside the vehicle passes through the gain adjusting variable resistor 34 and is then input to the buffer amplifying unit 35 in order to amplify it to a necessary input level for the power amplifying unit 36 at the subsequent stage. The vehicle exterior request signal amplified by the power amplification unit 36 is input to a parallel resonance circuit 37 including a capacitor and a coil. A magnetic circuit is formed in the trochoidal core 38, and the magnetic flux generated through the trochoidal core 38 by the input from the parallel resonance circuit 37 passes through the inductive coupling portion 39 and outputs a high-frequency current to the terminals ANT 1 and ANT 2.
In this way, in the communication device C of the present invention, the transmission signal (request signal) generated by the signal generation unit (system ECU 44 and transmission amplifier 32) is transmitted in the form of the signal current in the form of the transmission antenna unit (outdoor antenna 25). ) Will be sent.

  In the system configuration shown in FIG. 3, when the output of the communication device C is adjusted using the portable device 60 so as to be able to receive a request signal outside the vehicle at a position 2 m away from the vehicle body 70, the power consumption is about 0. It was 2W. On the other hand, a conventional bar antenna (an antenna formed by connecting a ferrite bar inductor and a capacitor between the terminals ANT1 and ANT2) is provided on the door handle, and 2 m away from the vehicle body using the portable device 60. When the output was adjusted so that the vehicle outside request signal could be received at the position, the power consumption was about 0.6 W. As described above, in the communication apparatus C of the present invention, the loop path X is appropriately set by selecting a portion (corresponding to the first portion and the second portion of the present invention) to which the signal output terminals ANT1 and ANT2 are connected. Thus, compared with the conventional system, it was possible to obtain the same radiated radio wave intensity with about one-third of the power consumption.

As described above, in the present invention, a high-frequency signal source having a long-wave band frequency is directly connected to and fed to a loop-like portion of the vehicle to supply a high-frequency current to the vehicle, and the vehicle body functions as an antenna (transmitting antenna unit). I let you. In this way, by energizing the loop path formed by the conductive member, the conventional bar antenna using the vehicle body becomes unnecessary, eddy current loss can be drastically reduced, and a large loop area can be secured. The antenna efficiency can be greatly improved.
In addition, the configuration of the smart entry system when the communication device of the present invention is provided in a vehicle is simpler than the conventional case where a ferrite bar or the like is provided on a door handle. To do. Further, when the transmission antenna unit is configured, the number of parts is reduced and the assembly process is simplified, so that the effect of cost reduction is great. Furthermore, since the conductive vehicle body itself becomes an antenna, it is not necessary to mount the antenna on the surface of the vehicle body, and it does not impose any restrictions on the vehicle design.

<Second Embodiment>
In 1st Embodiment, although the striker of the door catch part was comprised so that it might conduct | electrically_connect with a vehicle body, it may be comprised so that a striker and a vehicle body may not electrically conduct. FIG. 6 shows an example in which the striker and the vehicle body are electrically insulated from each other as the communication device of the second embodiment. Here, in particular, the part to which the output terminal of the transmission amplifier 32 is connected is different from the case of the first embodiment. The communication device of the second embodiment will be described below, but the description of the same configuration as that of the first embodiment will be omitted.

FIG. 6 shows a state in which the striker 79 of the door catch portion 77 is attached to the vehicle body 70 via the electrical insulator 78. That is, the striker 79 and the vehicle body 70 are not electrically connected. However, as in the first embodiment, in the door hinge portion 74, the vehicle body 70 and the door 80 are electrically connected. The output terminals (terminal ANT1 and terminal ANT2) of the transmission amplifier 32 are connected to the first part and the second part sandwiching the electrical insulator 78 in the middle of the loop path through which the signal current output from the transmission amplifier 32 flows. It is connected. Specifically, the above-described two output terminals, ANT1 and ANT2, are connected to a member 70a that is electrically connected to the vehicle body 70 and sandwiches the electrical insulator 78, and a striker 79 of the door catch portion 77. . However, the output terminal of the transmission amplifier 32 may be connected to the vehicle body 70 instead of the member 70a.
In this configuration, the member 70a electrically connected to the vehicle body 70 and the striker 79 correspond to the “first portion” and the “second portion” in the present invention. Also, in this configuration, a transmission amplifier 32 or the like as the signal generating unit is connected in series to the conductive member configured in a substantially loop shape with the vehicle body 70 and the door 80, thereby forming one loop path. It is a thing.

  FIG. 7 is a diagram schematically showing current paths x21 to x26 formed in the vehicle body 70 and the door 80, which are conductive members, when the vehicle door 80 is closed. As described in the first embodiment, the vehicle body 70 and the door 80 are electrically connected by the door hinge portion 74. Accordingly, as shown in FIG. 7, the striker 79 of the door catch portion 77 to which the terminal ANT2 is connected reaches the member 70a to which the terminal ANT1 is connected via the door 80, the door hinge portion 74, and the vehicle body 70. The signal current from the transmission amplifier 32 is fed to the loop path X (x21 to x26).

As described above, even if the electrical insulator 78 is provided in the middle of the loop-shaped path X formed by the conductive members such as the vehicle body 70 and the door 80, the output terminal of the transmission amplifier 32 is connected to the electrical insulator. By connecting in series with a portion sandwiching 78 (in this embodiment, the member 70a and the striker 79), it is possible to form the vehicle interior outside antenna 25 that acts as a loop antenna as in the first embodiment.
Such an electrical insulator 78 is not limited to being provided in the striker 79, and may be provided on the door hinge portion 74 side. Since the vehicle body is usually made of a steel plate, it is surprisingly complicated to provide an insulating portion as described above at any location. However, since the striker 79 and the door hinge portion 74 are attached to the vehicle body later, it is very easy to provide the electrical insulator 78 at these locations. Providing the electrical insulator 78 in this manner increases the power supply efficiency without causing the current flowing through the door 80 and the current of the power supply line from the transmission amplifier 32 to flow in opposite directions. As a result of actually making a prototype of a 134 kHz transmitter and receiver, it was confirmed that with this configuration, the power consumption was reduced to about one-tenth compared to the conventional antenna system.

<Third Embodiment>
The communication device according to the third embodiment is configured such that the output of the transmission amplifier 32 is supplied to the loop antenna without connecting the output of the transmission amplifier 32 to another member by wire connection. This is different from the first embodiment and the second embodiment that are connected to the site by wire. That is, the third embodiment is the same as the first embodiment, except that the output of the transmission amplifier 32 is not connected by wire when power is supplied to the loop antenna. Hereinafter, the communication apparatus according to the third embodiment will be described with reference to FIGS. 8 and 9, but the description of the same configuration as that of the first embodiment will be omitted.

FIG. 8 is an explanatory view showing a state in which the toroidal core 38 that is a magnetic body shown in FIG. 5 is disposed around the striker 72 included in the door catch portion 71. That is, in the communication apparatus according to the present embodiment, the transmission amplifier 32 is directly connected to the vehicle interior antenna 25 without using the terminals ANT1 and ANT2 and the conductive wires 81 and 82 shown in FIGS.
FIG. 9 is a diagram schematically illustrating current paths x31 to x35 formed in the vehicle body 70 and the door 80, which are conductive members, when the vehicle door 80 is closed. As described in the first embodiment, when the door 80 of the vehicle is closed, the door catch portion 71 having the striker 72 provided on the vehicle body 70 and the latch mechanism (not shown) provided on the door 80, The vehicle body 70 and the door 80 are electrically connected. Further, the vehicle body 70 and the door 80 are electrically connected by the door hinge portion 74. A toroidal core 38 shown in FIG. 5 is arranged around the striker 72 that connects the vehicle body 70 and the door 80. Therefore, since magnetic flux is generated so as to penetrate the annular toroidal core 38, an induced current flows through the striker 72 surrounded by the toroidal core 38. The induced current flows through the current paths x31 to x35. As described above, when the vehicle door 80 is closed, the vehicle body 70 and the door 80 are formed with the loop path X (x31 to x35, etc.) indicated by the arrows in FIG. An outdoor antenna 25 is realized. That is, in the communication apparatus of the present embodiment, the output from the transmission amplifier 32 is configured to be fed to the loop antenna 25 by magnetic field coupling with the loop path X.
Such a toroidal core 38 is not limited to being provided on the striker 72 but may be provided on the door hinge portion 74 side.

<Fourth embodiment>
In the above embodiment, the case where the terminal ANT1 and the terminal ANT2 are provided in each of the door catch portion 71 and the door hinge portion 74 of the vehicle body 70 has been described. You may connect to these parts.

  For example, as shown in FIG. 10, the transmission amplifier 32 is provided in a loop path along the edge of the opening of the trunk 90 of the vehicle, the edge of the opening of the back door of the vehicle, or the edge of the opening of the fuel filler. It is also possible to pass a signal current from. In this case, the mechanism for connecting the trunk 90, the back door, the fuel filler opening, and the like to the vehicle body 70 is the same as the mechanism for connecting the door 80 to the vehicle body 70. In particular, in the case of the trunk 90, the power feeding mechanism described above can be provided for the trunk catch portion that holds the trunk 90 in a closed state and the trunk hinge portion that rotatably supports the trunk 90.

  In addition, as shown in FIG. 10, the edge of the opening of the front window of the vehicle body 70, the edge of the opening of the window of the front seat side door, the edge of the opening of the window of the rear seat side door, oiling Loop paths X1, X2, X3, X4, etc. can be formed in the opening of the mouth. Therefore, not only as a communication device related to passenger getting on and off, but also a communication device for various uses such as opening / closing control of a window part, a fuel filler opening, and the like can be configured.

<Other embodiments>
The communication device C of the present invention may be provided not only in a device such as a vehicle described in the above embodiment, but also in another device or facility.
FIG. 11 shows an example in which the communication device of the present invention is configured by providing a loop path X4 through which a current flows at the entrance of a facility such as a room or a building. Also in this case, similarly to the above embodiment, the terminal ANT1 and the terminal ANT2 are connected to the frame part (edge part of the opening) of the rectangular door 80, and the loop current is supplied. Therefore, the frame portion of the door 80 corresponds to the conductive member of the present invention. As a result, the path X4 through which the loop current flows can be a loop antenna. In this example, the two signal output terminals of the terminal ANT 1 and the terminal ANT 2 are connected to the first part 82 and the second part 83 in the middle of the loop path X 4 formed in the frame part of the door 80. The two signal output terminals (ANT1 and ANT2) are respectively connected to the diagonal positions of the rectangular opening, and the distance between the first part 82 and the second part 83 is equal to the half circumference of the loop path X4. Equivalent to. Accordingly, two current paths are formed between the first part 82 and the second part 83 with the same path length and substantially the same impedance in the path. As a result, a current flows equally in each of the two current paths, and a magnetic field along the direction penetrating the loop surface can be generated in the loop.
By providing a smart entry system at the entrance of the facility in this way, it is possible to authenticate the portable device possessed by the facility user and determine whether or not the device has the right to use the device or the facility. it can. In this case, the door knob 81 can be provided with sensors and switches having the same functions as the unlocking operation sensor 22 and the locking operation switch 23 described above.

The device configuration of the transmission amplifier 32 is not limited to that illustrated in the circuit diagram of FIG. 5 and can be modified as appropriate. 12 and 13 are schematic diagrams of modifications of the transmission amplifier in the communication device of the third embodiment. For example, in the third embodiment, as shown in FIGS. 8 and 9, the toroidal core 38 is disposed so as to surround the striker 72, and an induced current is passed through the striker 72 at the inductive coupling portion 39. On the other hand, in the modification example illustrated in FIGS. 12 and 13, the toroidal core 27 is disposed so as to surround the striker 72, and is wound around the toroidal core 38 having the same configuration as that of the above embodiment. The conducting wire 26 wound around is disposed. Therefore, the magnetic flux generated through the core of the toroidal core 38 by the input from the parallel resonant circuit 37 induces a current in the annular conductor 26 at the inductive coupling portion 39, and the current induced in the conductor 26 is Then, a magnetic flux penetrating the inside of the toroidal core 27 is generated in the inductive coupling portion 28. As a result, the magnetic flux generated so as to penetrate the inside of the core of the toroidal core 27 causes an induced current to flow through the striker 27 at the inductive coupling portion 29.
As described above, when the input from the parallel resonant circuit 37 is supplied to the loop-shaped path X, it passes through one or a plurality of inductive coupling portions formed by combining one or a plurality of toroidal cores and annular conductors. Can be modified.

Functional block diagram of a communication apparatus according to the present invention Functional block diagram showing a main part of a communication apparatus according to the present invention Explanatory diagram showing a loop path through which current flows Explanatory diagram showing power supply status Block diagram showing amplifier for transmission Explanatory drawing which shows the electrical insulator which concerns on 2nd Embodiment. Explanatory drawing which shows the electric power feeding state which concerns on 2nd Embodiment Explanatory drawing which shows the toroidal core which concerns on 3rd Embodiment. Explanatory drawing which shows the electric power feeding state which concerns on 3rd Embodiment Explanatory drawing which shows the loop-shaped path | route which concerns on 4th Embodiment. Explanatory drawing which shows the loop-shaped path | route which concerns on another embodiment. Explanatory drawing which shows the toroidal core which concerns on another embodiment. Explanatory drawing which shows the electric power feeding state which concerns on another embodiment.

Explanation of symbols

60 Portable devices (portable receivers)
70 Car body 71 Door catch part (Catch part)
74 Door hinge (support)
X Loop path

Claims (3)

A communication apparatus comprising: a device or facility; a signal generation unit that generates a transmission signal for a portable receiver held by a user; and a transmission antenna unit that is connected to the signal generation unit and transmits the transmission signal. ,
The transmitting antenna unit, Ri loop antenna der capable energized looped path formed by using a conductive member constituting the equipment or the facility a signal current,
The conductive member is a vehicle body as the device,
One output terminal is connected to the catch portion of the opening and closing member provided at the opening of the vehicle body, another output terminal is connected to Ru communication device to a support portion connecting said closing member to said body of said signal generator. A communication apparatus comprising: a device or facility; a signal generation unit that generates a transmission signal for a portable receiver held by a user; and a transmission antenna unit that is connected to the signal generation unit and transmits the transmission signal. ,
The transmission antenna unit is a loop antenna capable of energizing a loop current path formed using a conductive member that constitutes the device or the facility with a signal current,
The conductive member is a vehicle body as the device,
The conductive member is formed in a substantially annular shape through an electrical insulating part in the middle, and a first part and a second part for connecting an output terminal of the signal generation part are provided at both ends of the conductive member, respectively. The signal generator and the conductive member are configured in series,
The electrically insulating portion, the vehicle body is provided in the opening closing member catch portion or the closing body arranged Ru communication device to a support portion connected to the vehicle body. A communication apparatus comprising: a device or facility; a signal generation unit that generates a transmission signal for a portable receiver held by a user; and a transmission antenna unit that is connected to the signal generation unit and transmits the transmission signal. ,
The transmission antenna unit is a loop antenna capable of energizing a loop current path formed using a conductive member that constitutes the device or the facility with a signal current,
The conductive member is a vehicle body as the device,
The output of the transmission signal from the signal generator is fed to the loop antenna by magnetic field coupling with the loop path,
The feed according to the magnetic field coupling is Ru communication device made of a magnetic material which the catch portion or the opening and closing of the closing member is arranged on the supporting portion connected to the vehicle body provided in the vehicle body opening.

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