JPH0339401B2 - - Google Patents

Description

[Detailed Description of the Invention] <<Industrial Application Field>> The present invention provides a method for locking and unlocking the rear opening/closing body of a vehicle, such as the trunk lid and hatch gate, not by using a mechanical key but by wirelessly. The present invention relates to a rear opening/closing body locking control device for a vehicle, and more particularly to a mounting structure for a loop antenna provided on the vehicle body side.

<<Background of the Invention>> As a rear opening/closing body locking control device for this type of vehicle, for example, there is a "radio key system" (Japanese Patent Application No. 132118/1983, unpublished) proposed earlier by the applicant. The device includes a portable transmitter that wirelessly transmits a predetermined unique signal, a switch that is installed near the rear opening/closing body of the vehicle body and outputs a start signal for locking/unlocking the rear opening/closing body in response to manual operation, and the above-mentioned switch. A loop antenna is provided near the switch and receives the unique signal radio wave, and the unique signal received through the loop antenna is provided on the vehicle body side and matches a unique signal preset on the vehicle body side. only when a start signal is output from the switch, and a unique signal matching means for determining whether or not the rear opening/closing body is locked, and an actuator for locking and unlocking the rear opening/closing body, and it is determined that the unique signals match. , and actuator driving means for locking or unlocking the actuator.

In other words, the rear opening/closing body locking control device of this vehicle has a transmitter instead of the driver having a key, and the person in possession of this transmitter can operate a switch installed near the rear opening/closing body such as the trunk lid. The structure is such that the rear opening/closing body can be opened/closed only when the rear opening/closing body is operated.

By the way, the transmitter carried by a driver or the like has a card-shaped body case the size of a business card, and can be easily accommodated in, for example, a breast pocket or a handbag. In other words, the transmitter is not necessarily located near the rear opening/closing body, but is held at various positions within a horizontal distance range of several tens of centimeters and with height differences. Therefore, it has been found that one of the points that needs to be taken into consideration when configuring this type of locking control device is the mounting position and arrangement of the loop antenna provided on the vehicle body.

<<Object of the Invention>> An object of the present invention is to provide a loop antenna suitable for the previously developed vehicle rear opening/closing body locking control device.

<<Structure of the Invention>> In order to achieve the above object, the present invention is characterized in that a loop antenna provided on the vehicle body side is arranged on the rear bumper.

<<Description of Examples>> Examples of the present invention will be described below along with experimental results by the inventors of the present invention.

FIG. 1 is a cross-sectional view showing the structure of a loop antenna in one embodiment of the present invention.

In the figure, a loop antenna 41 is constructed by sandwiching an enameled wire 42 wound into a substantially rectangular shape between flexible sheets 43 and 44 made of polyester or the like, and bonding both flexible sheets 43 and 44 by thermocompression bonding or adhesive. . Note that the outer peripheral end surface of the loop antenna 41 formed in this way is covered with the sealing material 4.
5 and is sealed to make it waterproof.

In other words, the loop antenna 41 is made of flexible sheets 43 and 44 that have spring properties, and has a restoring force against deformation in the in-plane direction of the loop.

As shown in FIG. 4, a pair of loop antennas 41 are attached to the upper surface of the rear bumper 23 at the rear of the vehicle body.

Next, Figures 2 and 3 show two examples of mounting structures.
Show one. First, in Figure 2, the rear bumper 23
The loop antenna 41 provided inside is attached to the inner surface of the skin material 25 on the upper end side of the rain force 24 with double-sided tape 51.
The vehicle rear end side of No. 1 is arranged so as to face the gap between the rear end surface of the reinforcement 24 and the facing skin material 25.

In addition, in Fig. 3, the rain force 24
A locking claw portion 61 is provided protruding from the inner surface of the skin material 25 on the upper end side toward the rear end of the vehicle, and a screw stand 62 is provided protruding from the inner side.
The front end in the width direction is screwed to the screw base 62 with a screw 63, and the rear end in the width direction is locked to the locking claw portion 61. At this time, loop antenna 4
Similarly to the example shown in FIG. 2, the rear end side in the width direction of the reinforcement member 1 is arranged so as to face between the rear end surface of the reinforcement 24 and the facing material 25.

As is well known, the rear bumper at the rear of a vehicle can hit walls, telephone poles, etc. when reversing.
This is where minor collisions are very common. For this purpose, the reinforcement is surrounded by a flexible resinous skin material, so that even if it is deformed by a minor collision, it can recover by itself if the degree of deformation is minor.

Therefore, with such a mounting structure, if the skin material 25 is deformed in a direction that narrows the gap between the reinforcements 24 due to a light collision, for example, the loop antenna 41 will not be destroyed along with the deformation of the reinforcements 24. It shrinks and deforms in the width direction. When the skin material 25 returns to its original shape, the loop antenna 41 also returns to its substantially straight shape in the width direction, returns to its original state, and can maintain its function as an antenna.

Next, the reason why the above-mentioned mounting position is optimal for transmitting and receiving signals will be clearly explained below using experimental results by the inventors of the present application.

The applicant has proposed that the rear three parts of the vehicle as shown in FIG.
We conducted an experiment by installing two loop antennas at , , and , respectively, and discovered the preferred mounting position and arrangement mode for the loop antennas. The content of the experiment and its results are shown in FIGS. 5 and 6.

In this experiment, a high-frequency current is supplied to a loop antenna installed on the vehicle body to form a predetermined magnetic field distribution toward the rear of the vehicle, and in this state the transmitter is moved from the rear of the vehicle toward the vehicle body. They then determined the point where the detection level of the transmitter's built-in loop antenna was 130 (dBμV/m), and determined this as the detectable distance. As shown in FIG. 6, the transmitter T is held approximately vertically at a height of 1.2 m above the ground. Therefore, the loop plane of the loop antenna incorporated therein is also approximately vertical.

In FIGS. 5 and 6, the first mounting location is the trunk finisher on both sides of the license plate (a cross section is shown in FIG. 5b). The two loop antennas 21, 21 used here are 120mm
It has an approximately rectangular shape of 100 mm. These were placed approximately vertically at a distance of 540 mm (as shown in figure a) and approximately 80 cm above the ground (as shown in figure c). and,
A high frequency current was supplied to the loop antennas 21, 21 so that the magnetic field strength was 113 dB at a position 1.5 m apart.

At this time, the lines of magnetic force of the magnetic field formed at the rear of the vehicle spread out from the loop antenna 21 in a substantially fan shape, as shown in Figure c, and the lines of magnetic force at a point beyond 70 cm are approximately parallel to the loop surface of the loop antenna 21. It's summery. As a result, the detectable distance with transmitter T was 81 cm.

Next, the second mounting position is the rear finisher (a cross section is shown in figure e). This rear finisher has a narrow space with a roughly triangular cross section, which was used as the mounting location. Therefore, the two loop antennas 22, 22 are long rectangular ones with a short side of 45 mm, and are placed at the center of the width of the vehicle body.
They were placed in a 700 mm section (as shown in figure d), and the short sides were arranged with an upward slope of about 60 degrees. The height above ground at this time is approximately 60cm. The loop antennas 22 and 23 have a length of 1.5 m.
High-frequency current was supplied so that the magnetic field strength was 111.5 dB at distant positions.

In this case, the lines of magnetic force of the magnetic field formed behind the vehicle are distributed in a substantially circular arc shape, as shown in FIG. Therefore, it was expected that the detectable distance would be longer than in the case of .

However, the magnetic environment was poor because there was a steel rain force 24 inside the rear bumper 23 directly below it, and the detectable distance was 72 cm. Note that when the loop surface of the loop antenna 22 is arranged so as to be substantially parallel to the oblique side of the triangular space, the detectable distance becomes even shorter.

The third mounting position is inside the rear bumper 23 shown in the above embodiment. The loop antennas 26, 26 have a long rectangular shape with a short side of 65 mm, and are arranged in an 800 mm section at the center of the width of the vehicle body (as shown in g in the same figure), and the long side on the rear side of the vehicle is in the rainforest. 24 so as to protrude 20 mm from the rear end (as shown in h of the same figure). The height of the loop antenna 26 above the ground at this time is 60 cm. and,
A high frequency current was supplied to the loop antennas 26, 26 so that the magnetic field strength was 124.5 dB at a position 1.5 m apart.

In this case, the lines of magnetic force of the magnetic field formed behind the vehicle are approximately radial, as shown in Figure i.
The detectable distance was 1.2m.

As a result of this experiment, as shown in Fig. 5, a suitable mounting position for the loop antenna installed on the vehicle body side is inside the rear bumper, and the mounting mode is such that a part of the loop antenna faces the rear end surface of the rain force 24. It has been found that it is better to face between the skin materials.

Note that according to this embodiment, the loop antenna 4
1 can be made thin and housed in a small space. Therefore, the loop antenna 41
There is no need to make the gap between the reinforcement 24 and the skin material 25 large.

In addition, in the embodiment of the above-mentioned mounting structure, the loop antenna 41 is attached to the skin material 2 on the upper end side of the rain force 24.
However, the present invention is not limited to this, and it goes without saying that it may be provided on the skin material 25 on the lower surface side of the reinforcement 24.

Furthermore, it is also possible to form the loop antenna itself using a conductor made of a material having spring properties.

<<Effects of the Invention>> As explained in detail above, according to the present invention, it is possible to change the shape of the skin material in accordance with the deformation of the skin material in the longitudinal direction of the vehicle body. It does not reduce its functionality.

Additionally, by installing the loop antenna inside the rear bumper, signals can be transmitted and received between devices inside and outside the vehicle, providing an antenna suitable for the vehicle rear opening/closing body locking control device developed by the applicant. can do.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the structure of a loop antenna according to an embodiment of the present invention, FIG. 2 is a sectional view showing an example of the mounting structure of the loop antenna, and FIG. 3 is a sectional view showing another example of the mounting structure of the loop antenna. Figure 4 is a cross-sectional view showing the mounting position of the loop antenna, Figure 5 is a diagram showing the mounting position of the loop antenna.
The figure shows the results of the experiments conducted by the inventors of the present application, and FIG. 6 is a diagram showing the contents of the experiments conducted by the inventors of the present application. 23...Rear bumper, 24...Rainforce, 2
5... Skin material, 41... Loop antenna, 42... Enamel wire, 43, 44... Flexible sheet, 45
...Sealing material, 51...Double-sided tape, 61...Latching claw portion, 62...Screw stand, 63...Screw.

Claims (1)

[Scope of Claims] 1. A portable transmitter that wirelessly transmits a predetermined signal, a loop antenna that is provided on the rear bumper of the vehicle body and receives the signal, and an actuator that locks and unlocks the rear opening/closing body of the vehicle. and actuator drive means for locking or unlocking the actuator based on a signal received by the loop antenna. A rear opening/closing body locking control device for a vehicle. 2. The loop antenna is held substantially horizontally on the inner surface of a skin material that surrounds the rainforth in the rear bumper with a predetermined gap, and a portion of the loop extends between the rear end surface of the rainforth and the skin facing the same. The vehicle rear opening/closing body locking control device according to claim 1, wherein the device is arranged so as to face a gap between the members.