JPS5939885B2 - Method for manufacturing abnormal voltage absorbing element - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing an abnormal voltage absorbing element in which a voltage dependent resistance element and a dielectric element are connected in parallel.

Various types of voltage-dependent resistance elements have been put to practical use, but the so-called zinc oxide varistor, which is mainly composed of zinc oxide, utilizes the nonlinear current-voltage characteristics of a shielding layer formed at grain boundaries. It is widely applied to high voltage stabilization circuits, surge absorbers, lightning arresters, etc.

On the other hand, when a steep waveform surge is applied or against noise, there are still some deficiencies in operation, so it is necessary to connect it in parallel with a dielectric element or connect an inductance. This supplements the deficiencies in functionality.

The present invention provides a manufacturing method for obtaining an abnormal voltage absorbing element in which such a voltage-dependent resistance element and a dielectric element are connected in parallel with high productivity and at low cost. explain.

In the manufacturing method of the present invention, an elongated element body constituting a voltage-dependent resistance element and an elongated element body constituting a dielectric element are laminated concentrically, and this laminated body is It is characterized by being cut at a predetermined position and separated into a plurality of pieces, and the following embodiments are available.

(Example 1) Methyl cellulose, methyl cellulose, Appropriate amounts of glycerin and water were added and stirred and kneaded to create a clay having viscosity suitable for extrusion molding.

Then, this clay was extruded into a cylindrical shape using a vacuum clay kneading machine to form a long rod-shaped body 1 as shown in FIG.

In addition, a clay having viscosity for extrusion molding was prepared from dielectric material powder containing barium titanate as the main component in the same manner as described above, and this clay was extruded using a vacuum clay kneading machine. A long cylindrical element body 2 as shown in FIG. 2 was formed.

Here, the outer diameter of the rod-like element 1 constituting the voltage-dependent resistance element is formed to be 0.03 to 0.08 mm smaller than the inner diameter of the cylindrical element 2 constituting the dielectric element. .

Thereafter, the rod-shaped element 1 constituting the voltage-dependent resistance element is inserted into the cylindrical element 2 constituting the dielectric element to form a laminated body, which is compressed with a hydrostatic press and then pressed at right angles to the longitudinal direction. The product was cut into a plurality of pieces at predetermined intervals in the direction of , to obtain a disc-shaped molded product 3 as shown in FIG.

Thereafter, this molded article 3 was fired at a high temperature, and a silver electrode 4 was formed on the opposing surface of this sintered body to obtain an abnormal voltage absorbing element as shown in FIG.

Here, by adjusting the viscosity of the clay for extrusion molding and adjusting the particle size of the raw material powder, the shrinkage rate during firing can be controlled, and the strength after sintering can be increased and integrated.

(Example 2) A long rod-shaped element body 1 was obtained by extruding the clay of the voltage-dependent resistor material in the same manner as in Example 1, and the rod-shaped element body 1 was cut and fired. After bonding, a dielectric material was laminated on the outer peripheral surface of each element by thermal spraying.

Thereafter, silver electrodes were formed on the opposing surfaces of this laminate to obtain a completed product.

Note that, in this embodiment, the dielectric material may be sprayed onto the outer peripheral surface of the rod-shaped element body 1 and then separated into a plurality of pieces.

The abnormal voltage absorbing elements obtained from the above Examples 1 and 2 are as follows:
It maintains the performance of conventional zinc oxide varistors, but adds capacitance, and has a surge voltage absorption function as well as a noise prevention function using capacitance.

Furthermore, it is also possible to reduce dV/di against steep surges.

In another embodiment of the manufacturing method of the present invention, a rod-shaped element of a voltage-dependent resistance element is immersed in a slurry of a dielectric material to adhere to the outer peripheral surface, and then dried and solidified to form a laminate. There is also a method of forming a dielectric material by using two extrusion molding machines and extruding the rod-shaped element of the voltage-dependent resistance element into a long length using one extrusion molding machine. A possible method is to form a laminate by extruding with another extruder so as to wrap the body.

Furthermore, the number of laminated layers of the element bodies constituting the voltage-dependent resistance element and the dielectric element body is not limited to two layers as in the above embodiment, but is alternately laminated in three, four, and five layers. It is also possible to form a multi-layered structure, and the order of lamination is not limited to the above embodiment.

As described above, according to the present invention, it is possible to provide an extremely excellent manufacturing method that allows an abnormal voltage absorbing element having a surge voltage absorbing function and a noise preventing function to be obtained with good mass production at a low cost.

[Brief explanation of the drawing]

1 to 4 are manufacturing process diagrams in a method of manufacturing an abnormal voltage absorbing element according to an embodiment of the present invention. 1... Rod-shaped element body, 2... Cylindrical element body,
4...Silver electrode.

Claims (1)

[Scope of Claims] 1. An elongated element body constituting a voltage-dependent resistance element and an elongated element body constituting a dielectric element are laminated concentrically,
An abnormality characterized in that an abnormal voltage absorbing element in which a voltage-dependent resistance element and a dielectric element are connected in parallel is obtained by cutting this laminate at a predetermined position in the longitudinal direction and separating it into a plurality of pieces. A method of manufacturing a voltage absorbing element. 2. Claim 1, characterized in that the laminate is separated and cut into a plurality of pieces, and then sintered, and electrodes are formed on the opposing surfaces.
The method for manufacturing the abnormal voltage absorbing element described in 2. 3. Spraying the material that will form the other element onto the outer peripheral surface of either one of the elongated element body that constitutes the voltage-dependent resistance element and the elongated element body that constitutes the dielectric element. 2. The method for manufacturing an abnormal voltage absorbing element according to claim 1, wherein a laminate is formed by: 4. Immersing either one of the elongated element body constituting the voltage-dependent resistance element and the elongated element body constituting the dielectric element in a slurry of the material for forming the other element body. 2. The method of manufacturing an abnormal voltage absorbing element according to claim 1, wherein the laminate is formed by drying and solidifying the laminate after adhering it to the outer circumferential surface. 5 Extrusion molding into a long shape of either one of the clay of the material for forming the element body constituting the voltage-dependent resistance element and the clay of the material for forming the element body constituting the dielectric element. The method for manufacturing an abnormal voltage absorbing element according to claim 1, wherein the other clay is attached to the outer peripheral surface of the formed body to form a laminate. 6. The method of manufacturing an abnormal voltage absorbing element according to claim 1, wherein an element body constituting a voltage-dependent resistance element and an element body constituting a dielectric element are alternately laminated.