JPH07183168A - Polarized capacitor with applied reverse voltage displaying function - Google Patents

Abstract

PURPOSE:To prevent the short-circuiting and deterioration of a polarized capacitor by giving it the function of indicating the reverse polarity of applied voltage. CONSTITUTION:A heater 6 is provided in series with a diode 5 between the anode lead wire 3 and cathode lead wire 4 of a polarized capacitor 2. Then a heat sensitive film 7 is stuck to a resin 1 on the surface of the heater 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polar capacitor, and more particularly to a polar capacitor having a reverse voltage application display function for indicating that a reverse voltage is applied to the polar capacitor.

[0002]

2. Description of the Related Art Conventionally, a capacitor has been used by inserting it between both poles of a DC power supply line in order to remove ripples and noise mixed in the DC power supply line. Among such capacitors, a fuse is integrally configured to prevent heat generation due to a short-circuit current when external noise is applied to the power line and the capacitor is short-circuited. Furthermore, the short-circuit can be visually judged. Therefore, a capacitor with an alarm is proposed in which the light emitting diode is turned on when the fuse is blown. Also, for the same purpose, there is also proposed a capacitor with a reverse polarity display in which a series circuit of a light emitting diode and a resistor which is in the forward direction when the polarity is reverse is attached in parallel with the capacitor. (See JP-A-3-10526)

In a conventional alarm-equipped capacitor, when a capacitor is connected in the reverse polarity of the DC power supply line, a fuse connected in series with the capacitor and blown by a current flowing at the time of the short circuit, and a fuse Is configured to include a switch that detects the fusing of the switch and closes its contact point, and a short-circuit display circuit that includes a light-emitting diode that is turned on by the operation of the switch.

However, when the capacitor is connected in the reverse polarity of the DC power supply line, the fuse is blown by the current flowing at the time of a short circuit, so that the capacitor cannot be used thereafter.

In the reverse polarity display function disclosed in Japanese Unexamined Patent Publication No. 3-10526, the light emitting diode is turned on by a temporary short-circuit current due to external noise on the DC power supply line, but when the external noise is removed, the light emitting diode is removed. However, there is a drawback that deterioration of the capacitor due to accumulated short-circuit current cannot be detected because the fire extinguishes.

[0005]

A polar capacitor having a reverse voltage application display function according to the present invention has a diode and a heating element connected in series between an anode terminal and a cathode terminal of the polar capacitor. Has a cathode connected to an anode terminal of the polar capacitor, a first terminal of the heating element connected to an anode of the diode, and a second terminal of the heating element connected to a cathode terminal of the polar capacitor. The polar capacitor, the diode, and the heating element are covered with an exterior resin, and a heat-sensitive film is attached to the heating element portion on the surface of the exterior resin.

[0006]

EXAMPLES The present invention will be described below with reference to examples.

FIG. 1 is a circuit diagram showing the configuration of an embodiment of a polar capacitor having a reverse voltage display function according to the present invention.

The lead wire 3 of the anode of the polarized capacitor 2 is connected to the cathode of the diode 5, and the lead wire 4 of the cathode is connected to the heating element 6. The anode of the diode 5 is connected to the heating element 6. The polar capacitor 2, the lead wire 3 and 4, the diode 5, and the heating element 6 are covered with the exterior resin 1. A heat sensitive film 7 is adhered to the exterior resin on the upper surface of the heating element 6.

Next, the operation of this embodiment will be described.
The polar capacitor with a reverse voltage display function according to the present invention operates to remove an AC component when used in a normal polarity state. In this state, the lead wire 3 is connected to the positive polarity side of the DC power supply line and the lead wire 4 is connected to the negative polarity side of the DC power supply line. Similarly, no current flows through 6.

Next, when the reverse voltage of the DC power supply line is applied to the capacitor 2, the lead wire 3 becomes the negative polarity and the lead 4 becomes the positive polarity, and the diode 5 is applied with the voltage in the forward direction. An electric current flows through the body 6. Heating element 6
Generates heat due to electric current, and the heat generation causes the heat-sensitive film 7 to change color due to thermal change.

Due to the discoloration of the heat-sensitive film 7, the capacitor 2
Since the reverse voltage application of is displayed, it can be known from the outside.

Further, even when a voltage due to noise or the like is temporarily applied as a reverse voltage to the capacitor 2, a current flows through the diode 5 and the heating element 6, so that the heat-sensitive film 7 is discolored. Therefore, even with a temporary reverse voltage, the accumulation can be known by the color change of the heat-sensitive film 7.

[0013]

As described above, in the present invention, since the reverse voltage application display of the polar capacitor is performed by the heat sensitive film, the capacitor may be mounted in the direction in which the reverse voltage is erroneously applied at the time of manufacturing the electronic device. Even if it happens, it can be easily found without deteriorating the capacitor, and even though it is mounted with normal polarity, temporary noise voltage is accumulated as a reverse voltage. This has the effect that this can be easily discovered even in the case.

[Brief description of drawings]

FIG. 1 is a circuit configuration diagram showing a configuration of an embodiment of the present invention.

[Explanation of symbols]

 1 Exterior Resin 2 Capacitor 3 Lead Wire (Anode) 4 Lead Wire (Cathode) 5 Diode 6 Heating Element 7 Thermal Film

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI Technical display location H01G 2/10 2/24 17/00 9/28 9174-5E H01G 1/04 9174-5E 4 / 40 Z 9375-5E 9/00 531

Claims (1)

[Claims] 1. A diode and a heating element connected in series between an anode terminal and a cathode terminal of a polar capacitor, the cathode of the diode being connected to the anode terminal of the polar capacitor, The first terminal is connected to the anode of the diode, the second terminal of the heating element is connected to the cathode terminal of the polar capacitor, and the polar capacitor, the diode, and the heating element are covered with an exterior resin. Then, a polar film capacitor with a reverse voltage application display function is characterized in that a heat sensitive film is attached to the heating element portion on the surface of the exterior resin.