JPS6074402A - Method of producing voltage nonlinear resistor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a method for manufacturing a sintered body containing lead oxide as a main component and having voltage non-linear resistance characteristics. It is.

[Technical background of the invention and between: IL (point) 1 Voltage non-curved resistor is generally called varistor 1r; l', ' 7 (
, its excellent non-direction #I'i, IE-? lf, fJl
r 'I', 1'+'J uses: J1. -(7j1,
Pressure stabilization, or surge tl', (with a yield of 1"l old and 1
．． Widely used for tame 1r'' mountain equipment and zajiabunba] 1
ing. A typical example is the recently developed 11-lead oxide varistor. This is mainly composed of oxide, lead, and bismuth, antimony, cobalt,
By adding manganese and chromium bamboo saponified products, %'li&gamma
"Lwa 7, Ij").

After shaping, it is constructed by gluing crystal mud 08 ryk L in a vacuum and gluing one pole (14V) to the sintered body.The non-old wire resistance characteristics are unique. Tosu, 91'
7: i'i body (r, 1M r++; lead particle and its surrounding 1
? Consisting of a grain boundary layer formed by b5 additives surrounding tl, f/ha nonlinear 111 anti-4 1'+;&:l'
It is believed that this is caused by the interface between the zinc chloride particles and the grain boundary layer.

However, when these voltage nonlinear resistors are mass-produced industrially, they not only suffer from a decline in nonlinear resistance and variations in their characteristics, but also other performance declines such as energized life and discharge withstand capacity. There is a problem that occurs.

One of the reasons for this can be the influence of factors other than the fired yarn in the manufacturing process.

Therefore, the heating method for firing n,'j, temperature rise and fall speed, maximum temperature and holding time, casing, and support plate.

Of course, it is important to stabilize the state and characteristics of the powder, but it is also important to use a skewer to stabilize the gas flow in the furnace, that is, the firing atmosphere.

At the experimental level, the utilization rate of the Matsufuru furnace, which has a stable relatively soft atmosphere in which the objects to be fired are fixed, is high; will inevitably become higher.

For this reason, the problem of stabilizing and uniformizing the firing atmosphere is a particularly important issue for short-term products.

By the way, in a tunnel-type firing furnace, it is known that when firing is performed in a state in which a predetermined air volume is forcibly generated in the furnace at a predetermined speed between the opening ends of the inlet and outlet of the kiln. Good wa! We are investigating how to obtain J-A.

In Figure 1, Sakabat 2 is filled with sake: t+゛x, L 7rr,
I-Sodalte (5s J, 7' in front view as seen from the open end of the forming furnace 1.

FI with 2 saggers rectangular parallelepiped shape] Harikikyu main body” (') t
: lil'l J'1i11-, : Place indigo 2b on 1',;;7shi, this 1no;1
]・- has been completed.

In addition, 匣ゆ（・Irj in the main body 2a, 7JI? The shape is I
12.1 (1 iT of vinegar is put into 11 bowls 2 and 1 spacer 5 into a small holding stand 61).

However, in the case of a tunnel-type pot, the shape of the pot is not necessarily the same as that inside the furnace.
There was a time when it was appropriate to write il' to yen/1 deaf person.

That is, in Fig. 2; the pair 1iiJ
ft 100 iil), the furnace air 4 does not flow between 6 and 3, and a stagnant state of the furnace air 4 occurs at 7Iris Gn as indicated by the arrow shown in the figure. This was an obstacle to stabilizing and homogenizing Qi.

[Object of the Invention] The present invention has been made in view of the above points i'1. The purpose of this invention is to provide a method for manufacturing a voltage nonlinear resistor having stable nonlinear resistance characteristics by stabilizing and uniformizing the firing conditions in a tunnel firing furnace. Overview] In order to achieve the above object, the present invention involves adding and mixing at least one metal oxide to zinc oxide as the main component, molding this mixture, and storing this molded body in a number of saggers. death,
The plurality of saggers are placed in a tunnel-type firing furnace so as to face each other at a predetermined interval in the axial direction of the tunnel-type firing furnace.
t) The direction of the tunnel type firing furnace is moved from one side end opening to the other side end opening, and a furnace air having a predetermined amount of air is forced at a predetermined speed between the openings of the tunnel type firing furnace. In the method for manufacturing a voltage non-linear resistor in which the saggers are fired in a state in which the saggers are formed, at least the side surfaces facing the adjacent saggers have a distance between opposing surfaces that gradually increases from the center toward the ends. It is characterized by being formed to expand.

[Embodiment of the Invention] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Main component zinc oxide (ZnO) 97.5%
and "Bismuth tsunide (13i20a), Cobalt 751 ide (CO208), Manganese itZ ide (MnO)
, antimony oxide (SbzOa), and A+chromium 9ide (Cr20B) powder at a rate of 0 leak 1/
) The 0th stiffness was mixed with a dispersant, a sifting agent, and a binder and put into a grinder, and then 80 ~ isow + φ water was added to form a slurry! Small 1-3 li4+' l
il 7) I",) to do.

The slurry after mixing and pulverization is dried and granulated using a soufflé dryer, and then molded into a 11-1 shuttle 40-130mm, 25mm square.

Then, these molded bodies were added to the initial number lll1. Store in H-. As shown in FIG. 1, this sagger consists of a long sword-shaped sagger body 2a, and a lid 2b which covers the opening of this body in the direction of the direction. Soshi cl koi
i l-) Place the gripping sagger 2 into the tunnel type firing furnace C month 1q1
The nozzles are arranged facing each other with the gap J7 spaced apart in one direction. By the way, as shown in FIG. 3, a 41': M l+; t: curved surface shape is used.

By using the four needles formed in this way and arranging them at 4jP in ``2'', the opposing sides of the adjacent pots 2 are aligned from the center 7a to the end 7b between the opposing surfaces. The distance will gradually increase.

On the other hand, the tunnel type kiln 1 has an internal capacity of approximately 2 m'. Then, with an effective volume ratio of 20 to 80%, one end of this tunnel type firing furnace is opened from ``21 (input ['') to the other (t'', lI i'iM t, + room III (exit)).
It is fired and sintered. During this firing, a tunnel type 5Y'8 blower is used to forcibly generate a predetermined internal furnace air flow from the outlet 7 to the inlet of the furnace at a predetermined speed, corresponding to the furnace internal volume and effective volume ratio. let The inside of the furnace is generated by providing a blower fan on the outlet side and an intake fan on the inlet side, and operating at least one of them. The effective volume ratio was 11. Air was fed using an indirect heating heat exchange method that utilized heat from the furnace wall to minimize the effect on temperature control.

Next, the fired material was used to completely complete the city resistance layer.
A high-resistance type material for finishing, which has been prepared in advance into a slurry state, is placed on the side of the material ω1. 50
Baking at 0 to 600°C.

Next, the inner core 1n1 of the sintered body was heated with aluminum 1(I).

Attach the poles by thermal spraying and apply voltage
・Manufacture.

Electrical 1. '1tjt ktr 41xl -6[
) 4' not shown in 1! Live in i.

Figure 4 i, j 120"C constant temperature (V in the arm) III
A (1111A: (j4 with non-11 flowing through the wire resistor
7. 10(l) of t(5EF, ) between the terminals at rP, 51
qi l0KA (8x20μ9) width part 1oo
The rate of change in the area of VlmA when applying up to 1[il (Δ
v/V1mA). In the famous diagram, the characteristics of the conventional non-linear resistor are shown in the diagram 1'1. Sword scraps.

From Figure 4, it is clear that the force is not 111.
Line (1) Antibodies are more pure than conventional antibodies.
ir, 'iL', rate of change of separation current with respect to IE,
The variation has been reduced by 1 to 11.

As is clear from Figure 5, the non-linear resistor according to the present invention has a higher resistance than the conventional non-linear resistor.

The rate of change and variation in VlmA with respect to large current pulses have also been significantly improved.

Although the characteristics improved in the rate of change, variation, etc. shown in FIGS. 4 and 5 can be obtained, it can be omitted for the following reason.

By the manufacturing method described above, a 1U non-linear resistor is composed of ZnO grains of about 10μ and a thin layer of less than 1μ centered around Bi 203 surrounding them.
, and there were countless rows of rows in all directions! It has a structure 1
It is believed that the pulse suppressing properties and life characteristics are due to the physical and chemical properties of the grain boundary layers in both regions. The properties of this grain boundary layer are determined by its composition and firing conditions, and it is important to create a uniform grain boundary layer. If the grain boundary layer is non-uniform, local deterioration occurs, increasing the variation in x%+'l.

Therefore, if the filler type and country are -W, it is considered that the ideal grain boundary layer is largely influenced by the firing conditions.

In the present invention, the opposite sides of the sagas that are in contact with each other are formed so that the distance between the opposing sides gradually expands from the center toward the genbu inscription 1. j 1i
The air inside the furnace generated by the illumination is sufficiently distributed in the space where the force between the boxes 4r1 and 1:1 is formed, and the air inside the furnace 1: [Acts to stop the phenomenon by 1 (h).

For this reason, one of the firing conditions, the lamp and the atmosphere, is stabilized.
This stabilizes the flow of air in the furnace and the amount of bismuth and antimony gas that is generated during firing, which stabilizes the grain boundary layer surrounding the lead oxide. The contribution is 1ζ and the force is strong.

Father, the usefulness of this invention is 11%, Q force 1te1
, 5 boxes, Ef; 1il) 6 special cases, early t
The early days of a it;+! l? (<l in le ru■111 Buddha.

In (tll; resistance leakage current) C (drinkage; 'A).
? Since Rino Ratsuki is distributed as shown in Figure 6, we can say a).

υ1j This is the variation distribution of the 1st and 2nd lines of the CI'IiI line in Figure 6, which has an improved shape. .

In Fig. 6, for example, if a product deviates from the control value by 30φ or more, it is determined to be a "lot defective."
Approximately 30% of the lots were considered defective.

According to the present invention, it is possible to completely eliminate defective lots as shown by the standard variation IrJ Ciil PI and +.

It should be noted that the material composition, manufacturing setup, and method shown in Example 7 are based on Bit lead oxide (Bit lead oxide), and are not necessarily limited to the above-mentioned Example. .

"Effects of the Invention" As explained above, the present invention provides l'1. In the manufacturing process of "IIg river non-use whip resistor, k"L formation condition'/Y7I
j! , which improves the current life, shock resistance, current resistance, etc., and provides highly reliable voltage non-IEt? P-i! You can make di(antibodies).

[Brief explanation of the drawing]

The 11th λ [is the 1st λ, which is located in the tunnel-type conversion reactor.
1. FIG. 2 is an AA section 1h1 diagram of FIG. 1. FIG.
The figure shows ISi]-leakage 111 during energization of a voltage non-conducting resistor according to an embodiment of the present invention. Characteristic diagram showing the flow relationship, Fig. 5 1'j: ('hj Q Mj flow loading characteristic diagram, Fig. 6: N)) fIl, '1 (= 'i>i1/4-゛ is a sexual rose,) indicates A'I:? Attached (nu (de b l). 1...Tunnel type/l゛1ξ1ξ formation furnace/1illHV4
...-Furnace wind 7-11il +A+7 a--Central part 711-4 Ryonia, 1 (Deputy Ben J!l' Shi Nori)
Yu Chika ((rl or 1 person) Figure 4: Figure 5

Claims (1)

[Claims] At least one or more metal oxides are added and mixed into the oxidation vessel of the main component, the mixture is molded, the molded bodies are stored in a plurality of saggers, and the plurality of saggers are fired in a tunnel type firing process. The tunnel-type firing furnace is disposed facing each other at a predetermined interval in the axial direction of the tunnel-type firing furnace, and is moved from one end opening of the tunnel-type firing furnace to the other end opening, and the tunnel In the method for manufacturing a voltage non-linear resistor, which is fired in a state where furnace air having a predetermined air volume at a predetermined speed is forcibly generated between the openings of a firing furnace, the saggers are at least in contact with each other. A method for manufacturing a voltage nonlinear resistor, characterized in that the side surfaces facing the pot are formed such that the distance between the opposing surfaces gradually increases from the center toward the ends.