JPS598983Y2 - Heatable flat glass indicator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heatable glass plate indicator, and more particularly to a heatable glass plate indicator that operates only when a heating current is applied to the heating conductive wire.

Conventionally, anti-fog rear window glass for automobiles has been manufactured using heating conductive wires with conductive paste baked onto the main surface of the window glass, or the resin film of so-called laminated glass in which the main surfaces of two opposing window glasses are bonded with a resin film. Anti-fog was achieved by heating the window glass by supplying a heating current from a power supply connected to a heating conductive wire such as a thin nichrome wire embedded inside.

In such an anti-fog rear window glass for automobiles, an indicator circuit for indicating the energization of the heating conductive wire is usually connected in parallel to the heating conductive wire circuit, independent of the same circuit. It is.

However, in such a heatable plate glass indicator, even if the conductor for supplying heating current to the heating conductive wire is disconnected and heating current is not applied to the heating conductive wire, an independent indicator circuit is activated. There is a drawback that the device operates unless a failure occurs and displays that a heating current is being applied to the heating conductive wire.

The present invention provides a heatable sheet glass with an indicator that eliminates the above-mentioned drawbacks, and includes a transparent sheet glass, a heating conductive wire attached to the main surface of the sheet glass, and a heating conductive wire connected to the heating conductive wire. A heatable plate glass comprising a power source, one end of which is connected to the middle of the heating conductive wire, and the other end of which is connected to the power source;
The indicator is a heatable plate glass comprising an electronic element or an electric circuit connected in parallel to the indicator and which continues to flow current when a high voltage, which occurs when the heating conductive wire is broken, is applied.

In this invention, the heating conductive wire attached to the main surface of the plate glass is a heating conductive wire with conductive paste baked onto the main surface of the plate glass, or a heating conductive wire such as a thin nichrome wire embedded in the resin film of the laminated glass. There may be.

Further, in the present invention, a light emitting diode or a pilot lamp that lights up at a constant voltage can be used as an indicator.

Furthermore, in the present invention, an electronic element or an electric circuit that continues to flow current when a high voltage is applied when the heating conductive wire is disconnected is provided with an electronic element or an electric circuit that continues to flow current when the starting voltage is normal operation of the heating current circuit of the heating conductive wire. higher than the voltage applied across the indicator at the time of the heating conductor, and lower than the voltage applied to the indicator (except in the case of zero) when a failure occurs in the heating current circuit of the heating conductive wire, such as a Zener diode. , or neon tubes, or various electronic circuits.

Furthermore, in the present invention, when the heating conductive wire is also used as an antenna wire, the indicator can be branched from the middle of the feeder wire drawn out from the heating conductive wire.

The heatable sheet glass indicator of the present invention has one end connected to the middle of a heating conductive wire attached to the main surface of the sheet glass, and the other end connected to one end of the heating conductive wire's power source, and the indicator. It consists of an electronic element or an electric circuit that continues to flow current when a voltage higher than a predetermined voltage is applied, which are connected in parallel to the indicator.If the heating electric circuit of the heating conductive wire is disconnected, the voltage across the indicator will decrease. becomes zero or momentarily exceeds a predetermined value.

If this voltage is zero, the indicator will not operate and will indicate that the heating conductive wire is not energized, and if this voltage momentarily rises above a predetermined value, an electric element connected in parallel with the indicator or A relatively large current flows through the electrical circuit, causing a voltage drop due to the electrical resistance of the indicator circuit, and the voltage across the indicator becomes below its operating point, the indicator does not operate and the heating conductive wire is energized in this case as well. It can be shown that it is not.

On the other hand, if there is no failure in the heating electric circuit of the heating conductive wire and a normal heating current is applied to the heating conductive wire, the voltage across the indicator will drop to the predetermined voltage due to a voltage drop due to the heating conductive wire. Therefore, no current flows through the electrical element or circuit connected in parallel to the indicator, and the voltage drop due to the electrical resistance of the indicator circuit becomes small, so the indicator operates and the heating conductive wire It is possible to display an indication that heating current is flowing through the device.

・Hereinafter, the present invention will be explained in detail with reference to the drawings.

In the drawing, a plurality of heating conductive wires/receiving antennas 12 are provided on the surface of an automobile rear window glass 11 in parallel to each other in the horizontal direction at the longitudinal center of the glass, and are connected to the generatrix lines at both ends of the width of the window glass 11. A second receiving antenna 15 having an optimum length for receiving FM broadcast waves in the ultra-high frequency band is provided on the surface of the upper window glass 11 of the heating conductive wire/receiving antenna 12. The uppermost part of the conductive wire/receiving antenna 12 and the second receiving antenna 15
A stub 16 whose tip is short-circuited is provided on the surface of the window glass 11 between the heating conductive wire and the uppermost conductive wire of the receiving antenna 12 and the second A lead conductive wire 19 is connected to the central portion of the second receiving antenna 15, and a lead conductive wire 19 is drawn out from the central portion of the second receiving antenna to the feed point.

Heating conductive wire/receiving antenna 12, bus bars 13, 14, second receiving antenna 15, stub 16, conductive wire 17.1
8 and the lead conductive wire 19 are obtained by printing a conductive paste made by paste-forming a low-melting glass powder containing fine silver particles in an organic solvent onto the window glass 11 by a silk screen method, and then baking the paste.

The bus bar 13 is connected to one end of a coil 21 wound around the core 20 via a lead wire 22, and the other end of the coil 21 is connected to the positive pole of a battery 24 whose negative pole is grounded via a switch 23. The coil 26 is connected to one end of the coil 26 through a lead wire 27, and the other end of the coil 26 is grounded.

At the end of the lead conductive wire 19 drawn out from the second receiving antenna 15, the outer conductor 31 connects the core wire 29 of the grounded coaxial cable 28, and the end is connected to the condenser 3.
0 to the antenna terminal of the receiver (not shown).

A coil 31 with an inductance of 2 mH, for example, for cutting off high frequency current is drawn out from the connection point between the core wire 29 of the coaxial cable 28 and the condenser 30, and an electric resistance 32 and a light emitting diode 33 as an indicator are connected in series to this. Ground one end of the

Further, a Zener diode 34 having a predetermined starting voltage is connected in parallel to the light emitting diode 33.

The receiving antenna 12 and the second receiving antenna 15, which also serve as heating conductive wires, can receive both AM and FM broadcasts with high gain.At the same time, when the rear window glass 11 of the automobile becomes foggy, the switch 23 can be turned on. Heating conductive wire 12
When energized, a voltage is applied to both terminals of the light emitting diode 33 and the heating conductive wire 12 emits light, indicating that the window glass is being heated.

In this case, since the voltage applied across the light emitting diode 33 is lower than the starting voltage of the Zener diode 34, no current flows through the Zener diode 34, and the voltage drop due to the resistance of the indicator circuit including the electric resistance 32 is small, and the light emitting diode 33 continues to emit light.

On the other hand, if the lead wire 22 is disconnected, the voltage across the light emitting diode 33 becomes zero, and no light is emitted and the heating conductive wire 12
Although it is clear that the display indicates that the power is not energized,
Even when the lead wire 27 is disconnected and no heating current is applied to the heating conductive wire 12, a large current flows through the Ritzener diode 34, where the voltage across the light emitting diode 33 is momentarily higher than the starting voltage of the Zener diode y. , a voltage drop occurs due to the resistance of the indicator circuit including the electric resistance 31 and the voltage across the light emitting diode 33 is lowered, so the light emitting diode 33 does not emit light and it is possible to indicate that the heating conductive wire 12 is not energized. can.

In addition, in the case where the heating conductive wire 12 is also used as an antenna wire as in this embodiment, the coaxial cable 28 whose terminal end connected to the heating conductive wire 12 extends to the dashboard of the automobile
Since the heating conductive wire 12 can be used as a branch line of the heating conductive wire, the light emitting diode 33 serving as an indicator can be easily set near the instrument panel even if the heating conductive wire 12 is provided on the rear window glass of the automobile.

The above has described one embodiment of the present invention, but the present invention may use a neon tube instead of the Zener diode 34, or use a transistor circuit that continues to flow current when a voltage higher than a predetermined voltage is applied. You can.

Further, in the present invention, a pilot lamp that is lit at a constant voltage may be used instead of the light emitting diode 33.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and are a front view and an electric circuit diagram of a rear window glass for an automobile. 11: Automobile rear window glass, 12: Heating conductive wire, 2
4: Battery, 32: Electrical resistance, 33: Light emitting diode, 34: Zener diode.

Claims (4)

[Scope of utility model registration request] (1) In a heatable plate glass consisting of a transparent plate glass, a heating conductive wire attached to the main surface of the glass plate, and a DC power source connected to the heating conductive wire, one end of the heating conductive wire is connected to the heating conductive wire. An indicator connected in the middle and having the other end connected to one end of the DC power supply, and an electronic element that continues to flow current when a high voltage generated at the cross section of the heating conductive wire is applied, which is connected in parallel to the indicator. or a heatable plate glass indicator consisting of an electrical circuit. (2) The heatable plate glass indicator according to claim 1, wherein the indicator is a light emitting diode. (3) The heatable sheet glass indicator according to claim 1 or 2, wherein the electronic element that continues to flow current when a high voltage is applied when the heating conductive wire is disconnected is a Zener diode. (4) The heatable plate glass indicator according to claim 1 or 2, wherein the electronic element that continues to flow current when a high voltage is applied when the heating conductive wire is disconnected is a neon tube.