JPH0329164B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an electronic component with a discharge gap used for surge prevention in electrical equipment and the like.

Conventional configuration and its problems In recent years, careful efforts have been made to prevent surges from destroying electrical equipment. In particular, prevention and countermeasures have become mandatory for electrostatic damage, lightning surges, etc.

Conventionally, as a countermeasure against lightning surges, a hole G is made in a printed circuit board 1 as shown in Fig. 1, a discharge gap is formed with an electrode 3, and a solid resistor 2 is connected to the hole G, as shown in Fig. 2. There is. Note that 4 and 5 are leads.

The operation of the electronic component shown in FIG. 1 is such that when a lightning surge occurs, it is discharged in the discharge gap G, and the surge is guided to the ground side to prevent the lightning surge from entering the next stage circuit. Furthermore, the added resistor 2 has the role of preventing electric shock when it comes into contact with the human body, since electricity flows in a loop from the power source through the ground.

Problems with such conventional electronic components include:
There were variations in discharge starting voltage, the size was large and not compact, and the assembly method required increased costs. In particular, since the discharge gap was located outside the product, there was a problem that the shape became large.

OBJECTS OF THE INVENTION In view of the above-mentioned drawbacks, it is an object of the present invention to provide a discharge gap electronic component which is compact in size and which integrates a discharge gap and a resistor.

Structure of the Invention The electronic component with a discharge gap of the present invention comprises a ceramic base having a film resistor on the outer peripheral surface thereof and an insulating coating applied to the film resistor, and a ceramic base having caps attached to both ends of the ceramic base. a pair of cap-shaped electrode terminals;
A discharge gap is formed between a pair of cap-shaped electrodes on the cap-shaped electrode terminal so as to be in contact with the insulating coating portion of the porcelain base.

With this configuration, the film resistor and the cap-shaped electrodes attached to both ends form a parallel circuit between the discharge gap and the resistor, which serves to pass lightning surges to the ground side and protect the next stage.

Configuration of Embodiment An embodiment of the present invention will be described below with reference to the drawings.

FIG. 3 shows a sectional view of a resistor with a gap according to an embodiment of the present invention. In FIG. 3, 11 is a cylindrical ceramic base with good heat dissipation, 12 is a film resistor, and grooves 12a and 12b are trimmed to make the resistor a specified resistance value.
Reference numerals 13 and 14 are cap-shaped electrode terminals mounted on film resistors, and lead wires 17 and 18 are mechanically and electrically connected by welding. Reference numerals 15 and 16 designate cap-shaped electrodes that have a discharge gap function and determine the gap dimension G. 19 is the large voltage of the film resistor,
A base insulating paint that protects from moisture, and 20 is an outer insulating paint. The cap-shaped electrodes 15, 16 are mounted on the cap-shaped electrode terminals 13, 14 so as to be in contact with the outer insulating coating 20.

The resistor with a gap configured in this way has the function of discharging at the discharge gap G when a lightning surge is input, passing the surge energy to the ground side, and protecting the next stage circuit. Also,
The resistor forms a loop circuit with the power supply circuit of the electrical equipment used, and is often connected to the external terminal of the electrical equipment, so it is necessary as a measure to prevent electric shock to the human body.

As described above, according to the electronic component of this embodiment, the discharge gap dimension is 2.4 mm ± 0.2 mm, which is highly accurate, and has the advantage that the discharge gap dimension can actually be checked. This is advantageous because it can be visually confirmed. In addition, at the discharge starting voltage, not only air discharge but also bath surface discharge occurs because the outer insulating paint and the cap-shaped electrodes 15 and 16 for discharge are in contact, and the variation in the discharge starting voltage is 3.5K to 4.0KV DC. It has little effect. The change in resistance value during the humid load life is small at 5 to 6% due to the undercoat insulation paint and outer insulation paint on the film resistor, and the withstand voltage is also A,
It is a film resistor that can withstand C1500V for 1 minute.

Effects of the Invention As described above, the present invention is capable of stabilizing the discharge starting voltage and making the gap size constant by using the cap-shaped electrode, and by improving the withstand voltage and the life of the resistor by using the undercoat and the outer insulating coating. There is something big.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a conventional electronic component, FIG. 2 is an equivalent circuit diagram of FIG. 1, and FIG. 3 is a front sectional view of a resistor with a discharge gap according to an embodiment of the present invention. 11...Porcelain base, 12...Film resistor, 1
3, 14... Electrode, 15, 16... Electrode for discharge gap, 17, 18... Lead wire, 19... Undercoat insulating paint, 20... Outer insulation paint, 21, 22...
...Resin for fixing lead wires.

Claims (1)

[Claims] 1. A porcelain base having a film resistor on its outer peripheral surface and having an insulating coating applied to the film resistor, a pair of cap-shaped electrode terminals attached to both ends of the porcelain base, and an insulating coating on the porcelain base. 1. An electronic component with a discharge gap, comprising: a pair of cap-shaped electrodes mounted on top of a cap-shaped electrode terminal so as to be in contact with the cap-shaped electrode terminal; and a discharge gap is formed between the cap-shaped electrodes.