JPH05167326A - Glass antenna for automobile - Google Patents

Abstract

PURPOSE:To improve a reception gain extending from an FM radio broadcasting wave to a TV broadcasting wave by providing a main element consisting of two pieces of wires being parallel to each other and a characteristic improvement auxiliary element connected thereto in the lower blank part of glass at the time of embedding blur-proof heating wires into the rear part windowpane of a vehicle. CONSTITUTION:In the lower blank part of heating wires provided on the rear part windowpane, a main element consisting of two parallel wires whose end parts are connected, while frothing the center line of the windowpane and also an auxiliary antenna which can improve the directivity or the adjustment of impedance is provided thereon. That is, in the inside of an automobile of a windowpane 1, plural blur-proof heating wires 2 are embedded in parallel to each other in advance and in the lower blank part, a main element 4 in which the end parts of two parallel wires are coupled by a vertical wire, an auxiliary element 5 positioned in the lower part and connected to the element 4 and a power feeding point 6 provided on the end part are formed. These elements are formed by screen printing of conductive paste.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a glass antenna provided on a rear window glass of a vehicle such as an automobile, and more particularly to a glass antenna suitable for receiving TV broadcast waves and FM radio broadcast waves.

[0002]

2. Description of the Related Art In recent years, there has been a demand for a glass antenna for a vehicle for receiving TV broadcast waves other than radio broadcast waves such as AM and FM, and a vertical antenna is provided on a front window glass. What is provided (Japanese Patent Laid-Open No. 61-203702),
Various proposals have been made, such as one in which an antenna for receiving FM radio broadcast waves and TV broadcast waves is provided in the upper margin of the anti-fogging heating wire of the rear window glass (Japanese Patent Laid-Open No. 61-121603). In glass, multiple heating wires occupy most of the area, so the occupied area of the antenna is small, and it is not always possible to obtain a sufficient reception gain not only with a single antenna but also with multiple antennas for diversity reception. I couldn't.

The present invention has been made in view of the above points, and even in a narrow space of a lower margin of a heating wire,
An object of the present invention is to provide a glass antenna for a vehicle which has an improved reception gain in a very wide frequency band from FM radio broadcast waves to TV broadcast waves UHF band.

[0004]

DISCLOSURE OF THE INVENTION The present invention is a glass antenna provided in a lower margin portion of a heating wire for anti-fogging of a rear window glass for a vehicle, which comprises two parallel lines having a length of 600 mm to 1300 mm. At least at one end,
The main elements connected by vertical lines between the end portions are arranged so as to cross the center line of the window glass, and in the horizontal direction beyond the center line of the window glass from the feeding point provided on the side part. It is characterized in that an L-shaped auxiliary element that extends and further extends vertically and is connected to the main element is arranged.

[0005]

The present inventors have made two parallel lines having a length of 600 mm to 1300 mm in the lower margin of the heating filament of the rear window glass for a vehicle, and at least at one end, between 200 mm from the end. By arranging the main elements connected by vertical strips so as to cross the center line of the window glass, the reception gain is high over a wide band from FM radio broadcast waves to TV broadcast waves, and it acts as a main antenna. According to the present invention, the present invention has been made, and an L-shape that extends in the horizontal direction from the feeding point provided on the lateral side beyond the center line of the window glass and further extends in the vertical direction upward and is connected to the main element. By arranging the auxiliary element in the shape, this part acts as an auxiliary antenna for improving the directional characteristics or adjusting the impedance to further improve the reception gain. Those that can be in.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the drawings. 1 to 5 show Embodiments 1 to 5 in which the glass antenna of the present invention is provided on a rear window glass for an automobile.
FIG.

Example 1 An example in which a single plate glass is attached to a rear window glass of an automobile, and as shown in FIG. 1, the heating wire strips 2, 2, ... Along with the bus bars 3 and 3, in the lower margin of the heating wire, the main element in which the ends of the two parallel wires are connected by the vertical wire, the auxiliary element 5, and the feeding point 6
Is formed by screen printing and firing with a conductive paste.

In the glass antenna for a vehicle thus obtained, the horizontal stripes of the auxiliary element 5 are disposed so as to cross the center line CL so that the main element 4 crosses the longitudinal center line CL of the window glass. The size of each part is A
_{1 = 1180mm, A 2 = 1400mm} , B = 700m
m, C = 1000 mm, D = 30 mm, E = 780 m
m, F = 80 mm, G = 20 mm, H = 30 mm FM radio broadcast waves in Japan and the United States of 76 MHz to 108 MHz, TV broadcast wave VHF band of 1 to 12 channels, TV broadcast wave UHF band of 470 MHz to 770 MHz When the average reception gain in the horizontal polarization is measured and the gain difference when the reception gain of the standard dipole antenna is 0 dB (hereinafter, abbreviated as dipole ratio) is shown, it is -18.3 dB,-, respectively. 19.1 dB, -1
The value is 8.0 dB, and the reception gain of a good glass antenna for vehicles that has been put to practical use is FM radio broadcast wave, T
The average value is about -20 dB, about -20 dB, and about -19 dB for V broadcast wave VHF band and TV broadcast wave UHF band, respectively.
Therefore, it can be seen that the antenna is superior in all bands and is a good antenna.

Embodiments 2 to 5 In Embodiment 2 shown in FIG. 2, both ends of the main element horizontal filament are connected by vertical filaments so that C = 800 mm. In Embodiment 3 shown in FIG. 3, I = I 1200mm, J = 20mm
(H = 20 mm), another element 7 having a size of C = 1200 m
m, D = 20 mm, Example 4 shown in FIG.
= 900 mm, J = 30 mm (H = 15 mm), another element 8 is added, and the size of the auxiliary element 5 is F = 65 mm. In Example 5 shown in FIG. C = 900 mm, D = 2
0 mm, I = 800 mm, J = 20 mm (H = 20
mm) and another element 10 with K = 100 mm are added, and an antenna 11 different from the present invention is arranged in the upper margin of the heating wire.

With such a glass antenna for a vehicle, FM radio broadcast waves of 76 MHz to 108 MHz, 1
TV broadcast wave VHF band in -12 channels, 470
When the reception gain (dipole ratio) in the horizontal polarization of the TV broadcast wave UHF band of MHz to 770 MHz is measured and shown as an average value, the antennas of Example 2 are -18.1d, respectively.
B, -18.9 dB, -18.3 dB, and the antennas of Example 3 are -18.5 dB, -18.8 dB, -1 respectively.
7.9 dB, and the antennas of Example 4 are -18.6.
dB, -18.5 dB, -18.1 dB, and the antennas of Example 5 are -18.3 dB, -18.6 dB,-, respectively.
The value was 18.2 dB, which was a good result almost the same as in Example 1.

In the fifth embodiment, it is preferable to perform diversity reception by combining the antenna of the present invention with another antenna 10 provided above the heating wire. The preferred embodiments have been described above, but the present invention is not limited to these, and various applications are possible.

Regarding the main element, the length C of each of the two horizontal filaments may be appropriately selected within the range of 450 to 1200 mm. The vertical length D is in the range of 10 to 60 mm, preferably 20 to 40 mm. Further, it is preferable that the main elements are arranged at substantially equal lengths from the center line CL.
The reception gain is higher than that in the case where the center line CL is extremely biased to the extent that the center line CL is not crossed to the left or right, which is preferable.

Regarding the auxiliary element 5, the reception gain is higher when the horizontal length E is made longer than the center line CL as compared with the case where the horizontal length E does not reach the center line CL from the feeding point provided on either side. Therefore, it may be appropriately selected within a range connectable to the main element. Further, the vertical length F is 30 to 100.
mm, preferably 40 to 90 mm.

Elements such as the additional auxiliary elements 7, 8, 9, and 10 are not necessarily required, but impedance adjustment, directivity improvement, wide band characteristic improvement, capacitive coupling with the heating wire, etc. may be performed. Various desired auxiliary elements can be added.

The glass antenna of the present invention can be used alone, but as shown in Example 5, the glass antenna provided in the upper margin of the heating wire, the glass antenna provided in the front window glass, and the side portion. Further favorable results can be obtained by performing diversity reception on FM radio broadcast waves and TV broadcast waves in combination with a glass antenna or a pole antenna provided on window glass.

When laminated glass is used for the rear window glass, the glass antenna may be formed by embedding a fine metal wire such as a copper wire in an intermediate film such as polyvinyl butyral.

[0017]

INDUSTRIAL APPLICABILITY In the glass antenna of the present invention, by connecting the auxiliary element of a specific shape to the main element of a specific shape, even if the glass antenna is provided in the narrow margin below the heating wire, the FM radio broadcast wave To improve the reception gain in a very wide frequency band of 76MHz to 770MHz from the TV broadcast wave to the UHF band, and it is possible to obtain even better results by performing diversity reception with an antenna provided elsewhere. Is.

[Brief description of drawings]

FIG. 1 is a front view showing a first embodiment in which a glass antenna of the present invention is provided on a rear window glass for an automobile.

FIG. 2 is a front view showing a second embodiment in which the glass antenna of the present invention is provided on a rear window glass for an automobile.

FIG. 3 is a front view showing a third embodiment in which the glass antenna of the present invention is provided on a rear window glass for an automobile.

FIG. 4 is a front view showing a fourth embodiment in which the glass antenna of the present invention is provided on a rear window glass for an automobile.

FIG. 5 is a front view showing a fifth embodiment in which the glass antenna of the present invention is provided on a rear window glass for an automobile.

[Explanation of symbols]

 1 plate glass 2 anti-fogging heating wire 4 main element 5 auxiliary element 6 feeding point 7, 8, 9, 10 another auxiliary element 11 another antenna

Claims (1)

[Claims] 1. A glass antenna provided in a lower margin portion of an anti-fog heating wire of a rear window glass for a vehicle, having a length of 6
The main element is composed of two parallel lines of 00 mm to 1300 mm, and at least at one end, the main element connected by a vertical line between the end and 200 mm is arranged so as to cross the center line of the window glass, and An L-shaped auxiliary element that extends horizontally from the feeding point provided on the side portion beyond the center line of the window glass and further extends vertically upward is connected to the main element. A characteristic glass antenna for automobiles.