JPH0138884Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a voltage nonlinear resistor used as a protection circuit for communication equipment, and can provide a protection circuit with superior performance and lower cost than conventional protection circuits. It is intended to provide a voltage non-linear resistor.

The communication equipment protection circuit is constructed as shown in FIG. In the figure, 1 is a three-pole detonator, 2,
3 is a resistor or a coil, 4 and 5 are voltage nonlinear resistors whose main component is zinc oxide, 6 and 7 are Zener diodes, and 8 is a communication device. _L1 ,
L ₂ is the communication line and E is the ground.

The present invention relates to the voltage nonlinear resistors 4 and 5 shown in FIG. 1, and is useful when the protection circuit shown in FIG. 1 is integrated as a communication protector.

The voltage nonlinear resistor used in conventional communication protectors has two disk-shaped elements and is large in shape.
And it is necessary to solder 4 lead wires,
The shape of the communication protector itself is large, and the number of man-hours required is high, which is a factor in high costs.

In order to solve these problems, the voltage nonlinear resistor of the present invention has a single element that has the functions of two disc-shaped elements, and can be wired on a printed circuit board etc. without lead wires. It is designed so that it can be soldered directly to the conductive part.

Hereinafter, the present invention will be described in detail based on embodiments with reference to the accompanying drawings.

FIG. 2, FIG. 3, FIG. 4, and FIG. 5 show a perspective view, a top view, a bottom view, and a sectional view of a voltage nonlinear resistor according to an embodiment of the present invention.

Reference numeral 9 denotes a sintered body of a flat plate-shaped voltage non-linear resistor containing zinc oxide as a main component, and the thickness of this sintered body 9 is approximately constant. Reference numerals 10 and 11 denote electrodes formed as a pair on one plane of the sintered body 9, and these electrodes 10 and 11 extend through the side surface of the sintered body 9 to the other plane of the sintered body 9. It is formed. Reference numeral 12 denotes another electrode formed on the other plane of the sintered body 9, with a part thereof extending to the end of the other plane of the sintered body 9. In this case, a voltage nonlinear resistor is formed by the electrodes 10 and 12 and the electrodes 11 and 12 via the sintered body 9, and these correspond to the voltage nonlinear resistors 4 and 5 in FIG. Moreover, these voltage-current characteristics are almost the same, and when a surge voltage enters between a line and the ground, the surge voltage that transfers between lines is almost zero.

In addition, since there are three electrode parts on the other plane of the sintered body 9 as shown in Fig. 5, it is possible to solder them onto the wiring board as shown in Fig. 6, which greatly reduces the number of man-hours. Become. In FIG. 6, 13a,
13b and 13c are solder, especially solder 13
c can be seen because a part of the electrode 12 on the other plane extends to the end of the other plane, which ensures that the electrode 12 on the other plane is connected to the conductor part on the wiring board. You can confirm that the soldering has been completed. 14 is a printed circuit board on which communication lines L ₁ , L ₂ and earth E are wired as conductors;
This is a wiring board such as an alumina board. Here, the sintered body 9 may be made wider and a plurality of pairs of electrodes 10 and 11 may be formed on one plane.

Incidentally, in order for the voltage nonlinear resistor as shown in the present invention to perform its original function, it is necessary to structurally satisfy the following conditions. That is, when the thickness of the sintered body 9 is t, the distance W ₁ between the electrodes 10 and 11 is
W ₁ must be >2t. Moreover, the distance W ₂ between the electrodes 10 and 12 or between the electrodes 11 and 12 is
W ₂ >t must be satisfied. When this condition is not satisfied, the current does not flow inside the sintered body 9 but flows on the surface of the sintered body 9, making it easy to deteriorate.

As mentioned above, the voltage nonlinear resistor of the present invention has the functions of two conventional disk-shaped elements with one element, and all three electrodes are formed on one side of the sintered body. It has features such as being able to be soldered onto a wiring board without lead wires, and has a smaller size and cost reduction compared to conventional communication protectors, making it suitable for practical use. It is of great value.

[Brief explanation of the drawing]

Fig. 1 is an electric circuit diagram showing a protection circuit for communication equipment, Fig. 2 is a perspective view showing an embodiment of the voltage nonlinear resistor of the present invention, and Fig. 3 is a top view of the same voltage nonlinear resistor. Figure 4 is a bottom view of the same voltage nonlinear resistor.
FIG. 5 is a sectional view of the same voltage non-linear resistor, and FIG. 6 is a perspective view showing the voltage non-linear resistor of the present invention mounted on a wiring board. 9... Voltage nonlinear resistor sintered body, 10, 11,
12...electrode.

Claims (1)

[Scope of utility model registration request] A pair of 1 is attached to one of the opposing surfaces of a flat plate-shaped voltage nonlinear resistor sintered body containing zinc oxide as a main component.
A set or multiple sets of electrodes are formed, this electrode is formed on the other opposing surface through the side surface of the sintered body, and another electrode is formed on the other opposing surface. , a voltage nonlinear resistor formed by extending a part of this one electrode to the end of the other surface.