JPS6235244B2 - - Google Patents
Info
- Publication number
- JPS6235244B2 JPS6235244B2 JP55131563A JP13156380A JPS6235244B2 JP S6235244 B2 JPS6235244 B2 JP S6235244B2 JP 55131563 A JP55131563 A JP 55131563A JP 13156380 A JP13156380 A JP 13156380A JP S6235244 B2 JPS6235244 B2 JP S6235244B2
- Authority
- JP
- Japan
- Prior art keywords
- raw material
- resistor
- nonlinear resistor
- material powder
- nonlinear
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 claims description 40
- 239000000843 powder Substances 0.000 claims description 32
- 239000002994 raw material Substances 0.000 claims description 27
- 239000011787 zinc oxide Substances 0.000 claims description 20
- 239000013078 crystal Substances 0.000 claims description 12
- 239000002245 particle Substances 0.000 claims description 12
- 238000000034 method Methods 0.000 claims description 10
- 238000005245 sintering Methods 0.000 claims description 10
- 239000000654 additive Substances 0.000 claims description 9
- 230000000996 additive effect Effects 0.000 claims description 9
- 238000004519 manufacturing process Methods 0.000 claims description 8
- 229910044991 metal oxide Inorganic materials 0.000 claims description 8
- 150000004706 metal oxides Chemical class 0.000 claims description 8
- 230000002093 peripheral effect Effects 0.000 claims description 4
- 239000000203 mixture Substances 0.000 claims 4
- 238000001035 drying Methods 0.000 claims 1
- 239000002184 metal Substances 0.000 claims 1
- 229910052751 metal Inorganic materials 0.000 claims 1
- 230000003647 oxidation Effects 0.000 claims 1
- 238000007254 oxidation reaction Methods 0.000 claims 1
- 229910015902 Bi 2 O 3 Inorganic materials 0.000 description 6
- 230000000694 effects Effects 0.000 description 6
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- 239000000919 ceramic Substances 0.000 description 3
- 239000012212 insulator Substances 0.000 description 3
- 230000007774 longterm Effects 0.000 description 3
- 230000002159 abnormal effect Effects 0.000 description 2
- 238000000748 compression moulding Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 239000006096 absorbing agent Substances 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 238000010304 firing Methods 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
Landscapes
- Compositions Of Oxide Ceramics (AREA)
- Thermistors And Varistors (AREA)
Description
【発明の詳細な説明】
本発明は酸化亜鉛を主成分とする非直線抵抗体
の製造方法に関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a nonlinear resistor containing zinc oxide as a main component.
従来から電気系統において、例えば落雷または
系統の切り換えなどにより起り得る異常電圧を除
去し電気系統や電気機器を保護するために、サー
ジ・アブソーバ及び避雷器などの過電圧保護装置
が使用されてきた。 Overvoltage protection devices such as surge absorbers and lightning arresters have traditionally been used in electrical systems to protect electrical systems and electrical equipment by removing abnormal voltages that may occur due to lightning strikes or system switching, for example.
この過電圧保護装置には、正常な電圧でほぼ絶
縁特性を示し、異常電圧が印加されたときに比較
的低抵抗値になる非直線抵抗体が用いられる。こ
の非直線抵抗体として、すぐれた電圧・電流非直
線性を有する酸化亜鉛を主成分とする金属酸化物
焼結体がある。 This overvoltage protection device uses a nonlinear resistor that exhibits substantially insulating properties at a normal voltage and exhibits a relatively low resistance value when an abnormal voltage is applied. As this nonlinear resistor, there is a metal oxide sintered body whose main component is zinc oxide, which has excellent voltage and current nonlinearity.
電気系統の電圧が例えば送変電系統で500kVな
いし1000kVという高い電圧になると、過電圧保
護装置例えば避雷器で使用される非直線抵抗体の
形状も例えば直径80〜150mmの円板という大形の
ものが必要になる。こうした大形の非直線抵抗体
では電圧・電流非直線性、放電耐量、長期課電に
耐える耐久性などの性能の向上のため、抵抗体内
部の抵抗分布の均一性が要求される。 When the voltage of an electrical system reaches a high voltage of 500kV to 1000kV in a transmission and substation system, the shape of the nonlinear resistor used in overvoltage protection devices such as lightning arresters needs to be large, such as a circular plate with a diameter of 80 to 150 mm. become. These large nonlinear resistors require uniform resistance distribution inside the resistor in order to improve performance such as voltage/current nonlinearity, discharge withstand capacity, and durability to withstand long-term electrification.
しかしながら従来の非直線抵抗体は、抵抗体内
部で均一な抵抗分布が得られなかつた。このため
低抵抗のところの電流密度が大きくなり放電耐量
や長期課電に耐える耐久性が劣るという欠点があ
つた。また、抵抗分布が均一である場合に比べて
有効に使い得る体積が小さく同じ電圧・電流非直
線性を得るには、均一である場合よりも大形のも
のが必要とされた。 However, conventional non-linear resistors do not provide a uniform resistance distribution inside the resistor. As a result, the current density increases at low resistance points, resulting in poor discharge capacity and durability for long-term electrification. In addition, the usable volume is smaller than when the resistance distribution is uniform, and in order to obtain the same voltage/current nonlinearity, a larger one is required than when the resistance distribution is uniform.
本発明は、上記の欠点を除去するためになされ
たもので、抵抗体内部の抵抗分布が均一である金
属酸化物非直線抵抗体の製造方法を提供するもの
である。 The present invention was made to eliminate the above-mentioned drawbacks, and provides a method for manufacturing a metal oxide nonlinear resistor in which the resistance distribution inside the resistor is uniform.
本発明者は、非直線抵抗体の抵抗体内部の抵抗
分布を均一にする方法を見出すため種々研究し
た。その結果、非直線抵抗体を構成している酸化
亜鉛結晶粒子の粒成長に影響を及ぼす効果を持つ
添加成分を焼結時に酸化亜鉛結晶粒子の大きさを
抵抗体内部で均一にするように分布させれば、非
直線抵抗体内部で均一な抵抗分布を持つた非直線
抵抗体が得られることがわかつた。 The present inventor conducted various studies in order to find a method for making the resistance distribution inside a non-linear resistor uniform. As a result, the additive components that have the effect of influencing the grain growth of the zinc oxide crystal particles that make up the nonlinear resistor are distributed so that the size of the zinc oxide crystal particles becomes uniform inside the resistor during sintering. It was found that a nonlinear resistor with a uniform resistance distribution inside the nonlinear resistor can be obtained by doing so.
本発明は、この事実に基づくものである。以下
本発明を図面と共に実施例によつて説明する。 The present invention is based on this fact. The present invention will be explained below by way of examples together with drawings.
実施例 １
ZnOを主成分とし、添加成分の一つとして
Bi2O3を0.5モル％を含む第一の非直線抵抗体原料
粉末を作る。次にBi2O3を0.51〜1.5モル％含み、
他の成分は第一の非直線抵抗体原料粉末と同じ量
だけ含む第二の非直線抵抗体原料粉末を作る。Example 1 ZnO as the main component and as one of the additive components
A first nonlinear resistor raw material powder containing 0.5 mol% Bi 2 O 3 is made. Next, it contains 0.51 to 1.5 mol% Bi 2 O 3 ,
A second nonlinear resistor raw material powder containing the other components in the same amount as the first nonlinear resistor raw material powder is prepared.
第１図に示す如く、円筒状の金型１に円盤状の
鉄板２を嵌合してなる圧縮成形金型３中に、円筒
状容器４を配置しておき、この円筒状容器４内に
第一の非直線抵抗体原料粉末５を充填し、その外
側に第二の非直線抵抗体原料粉末６を充填した後
円筒状容器４を引き抜き、第２図に示す如く加圧
部材７により所要の加圧力をもつて圧縮成形して
成形体を得る。 As shown in FIG. 1, a cylindrical container 4 is placed in a compression molding mold 3 made by fitting a disc-shaped iron plate 2 into a cylindrical mold 1. After filling the first non-linear resistor raw material powder 5 and filling the outside with the second non-linear resistor raw material powder 6, the cylindrical container 4 is pulled out, and the pressure member 7 is applied as shown in FIG. A molded product is obtained by compression molding with a pressure of .
然る後、乾燥しあるいは側面にセラミツク絶縁
物を塗布した後に乾燥し、1000〜1500℃の温度で
焼結する。これによつて出来た焼結体の外側周面
を一定の厚さに研磨し、また上下の研磨面に電極
を付けて非直線抵抗体を形成する。 After that, it is dried or coated with a ceramic insulator on the sides, dried, and sintered at a temperature of 1000 to 1500°C. The outer peripheral surface of the resulting sintered body is polished to a constant thickness, and electrodes are attached to the upper and lower polished surfaces to form a nonlinear resistor.
このようにして得られた非直線抵抗体は、抵抗
体内部の抵抗分布が均一になる。第３図は、非直
線抵抗体に1mAの電流を流したとき抵抗体の径
方向の電流分布で、縦軸は抵抗体中心部に流れる
電流を100％としたときの電流、横軸は円心から
径方向に測つた距離である。第３図実線Ａは、第
一の非直線抵抗体原料粉末のみで成形して得られ
た非直線抵抗体の電流分布である。この非直線抵
抗体は、焼結時に側面よりBi2O3が蒸発するため
あるいは側面に塗布したセラミツク絶縁物の成分
が側面から内部へ拡散するため外周縁部の酸化亜
鉛結晶粒子が内部に比べて小さく外周縁部附近が
高抵抗になり電流が流れにくくなつている。第３
図点線Ｂは、本実施例により得られた非直線抵抗
体の電流分布である。この非直線抵抗体は、外周
縁部に焼結時に酸化亜鉛結晶粒子の粒成長を促進
するBi2O3を内部より多く含むため、外周縁部の
酸化亜鉛結晶粒子が内部と同程度に粒成長し外周
縁部の抵抗が内部と同程度になり、電流は抵抗体
内部を一様に流れる。 The nonlinear resistor thus obtained has a uniform resistance distribution inside the resistor. Figure 3 shows the current distribution in the radial direction of the resistor when a 1 mA current is passed through the non-linear resistor. The vertical axis is the current when the current flowing through the center of the resistor is taken as 100%, and the horizontal axis is the circle. It is the distance measured in the radial direction from the center. The solid line A in FIG. 3 is the current distribution of the nonlinear resistor obtained by molding only the first nonlinear resistor raw material powder. In this non-linear resistor, the zinc oxide crystal particles on the outer edge are smaller than the inside because Bi 2 O 3 evaporates from the side surface during sintering, or because the components of the ceramic insulator coated on the side surface diffuse into the inside from the side surface. It is small and has high resistance near the outer periphery, making it difficult for current to flow. Third
The dotted line B in the figure is the current distribution of the nonlinear resistor obtained in this example. This non-linear resistor contains more Bi 2 O 3 in the outer periphery than in the inside, which promotes grain growth of zinc oxide crystal particles during sintering, so that the zinc oxide crystal particles in the outer periphery are grained to the same extent as in the inside. As the resistor grows, the resistance at the outer periphery becomes comparable to that inside the resistor, and current flows uniformly inside the resistor.
実施例 ２
ZnOを主成分とし、添加成分の中にBi2O3、
Co2O3、MnO2を夫々0.5モル％含む第一の非直線
抵抗体原料粉末を作る。次にCo2O3、MnO2を
0.51〜1.5モル％含み他の成分は第一の非直線抵
抗体原料粉末と同じ量だけ含む第二の非直線抵抗
体原料粉末を作る。Example 2 The main component is ZnO, and the additive components include Bi 2 O 3 ,
A first nonlinear resistor raw material powder containing 0.5 mol % of each of Co 2 O 3 and MnO 2 is prepared. Next, add Co 2 O 3 and MnO 2
A second nonlinear resistor raw material powder containing 0.51 to 1.5 mol % and the same amount of other components as the first nonlinear resistor raw material powder is prepared.
このようにして作つた第一、第二の非直線抵抗
体原料粉末をもつて、実施例１と同様の方法で非
直線抵抗体を形成する。 Using the first and second nonlinear resistor raw material powders thus produced, a nonlinear resistor is formed in the same manner as in Example 1.
このようにして得られた非直線抵抗体は、外周
縁部に多く含まれているCo2O3，MnO2が焼結時
に酸化亜鉛結晶粒子の粒成長を促進するBi2O3の
蒸発を抑制し、その結果、抵抗体外周縁部の酸化
亜鉛結晶粒子が内部と同程度に粒成長し、抵抗体
内部の抵抗分布が均一になり、実施例１と同等の
効果が得られる。 The non-linear resistor obtained in this way has a large amount of Co 2 O 3 and MnO 2 contained in the outer periphery, which prevents the evaporation of Bi 2 O 3 that promotes the growth of zinc oxide crystal particles during sintering. As a result, the zinc oxide crystal particles at the outer peripheral edge of the resistor grow to the same extent as inside the resistor, and the resistance distribution inside the resistor becomes uniform, resulting in the same effect as in Example 1.
実施例 ３
ZnOを主成分とし、添加成分の一つとして
Sb2O3を1.0モル％含む第一の非直線抵抗体原料粉
末を作る。次にSb2O3を0.1〜0.99モル％含み他の
成分は第一の非直線抵抗体原料粉末と同じ量だけ
含む第二の非直線抵抗体原料粉末を作る。Example 3 ZnO as the main component and as one of the additive components
A first nonlinear resistor raw material powder containing 1.0 mol% of Sb 2 O 3 is prepared. Next, a second nonlinear resistor raw material powder containing 0.1 to 0.99 mol % of Sb 2 O 3 and the same amount of other components as the first nonlinear resistor raw material powder is prepared.
このようにして作つた第一、第二の非直線抵抗
体原料粉末をもつて、実施例１と同様の方法で非
直線抵抗体を形成する。 Using the first and second nonlinear resistor raw material powders thus produced, a nonlinear resistor is formed in the same manner as in Example 1.
このようにして得られた非直線抵抗体は、抵抗
体の外周縁部に焼結時に酸化亜鉛粒子の粒成長を
抑制するSb2O3を内部より少なく含むため、外周
縁部の酸化亜鉛粒子が内部と同程度に粒成長し、
抵抗体内部の抵抗分布が均一になり、実施例１と
同等の効果が得られる。 The nonlinear resistor obtained in this way contains less Sb 2 O 3 at the outer periphery of the resistor than the inside, which suppresses the grain growth of zinc oxide particles during sintering. grains grow to the same extent as inside,
The resistance distribution inside the resistor becomes uniform, and the same effect as in Example 1 can be obtained.
以上説明したように、本発明の金属酸化物非直
線抵抗体の製造方法により形成した非直線抵抗体
は、抵抗体内部の抵抗分布が均一である。このた
め、電流を流すのに有効に使い得る体積が増大
し、従来よりも小形のもので同じ電圧・電流非直
線性を得ることができる。また、電流が抵抗体内
を一様に流れるため、特定の部分のみ劣化するこ
とが無くなり放電耐量や長期課電に耐える耐久性
などの性能が向上する。 As explained above, the nonlinear resistor formed by the method for manufacturing a metal oxide nonlinear resistor of the present invention has a uniform resistance distribution inside the resistor. Therefore, the volume that can be effectively used to flow current increases, and the same voltage/current nonlinearity can be obtained with a smaller device than in the past. In addition, since the current flows uniformly within the resistor, there is no possibility of deterioration in specific parts, improving performance such as discharge withstand capacity and durability to withstand long-term electrification.
なお、上記実施例では第二の非直線抵抗体原料
粉末として、焼成時酸化亜鉛結晶粒子の粒成長を
促進する成分のみあるいは抑制する成分のみの量
を変化させたものを用いたが、促進あるいは抑制
する成分を数種にわたつて抵抗体内の酸化亜鉛結
晶粒子の粒成長を一様にするように変化させた第
二の非直線抵抗体原料粉末を用いても、同様の効
果を得ることができる。 In the above examples, the second nonlinear resistor raw material powder used was one in which the amount of only the component that promotes or only the component that suppresses grain growth of zinc oxide crystal particles during firing was varied. A similar effect can be obtained by using a second nonlinear resistor raw material powder in which several types of suppressing components are used to uniformize the grain growth of zinc oxide crystal particles in the resistor. can.
また、上記実施例では、第一の粉末の外側に第
二の粉末を充填する場合を説明したが、本発明は
これに限ることなく第一、第二の粉末の外側に更
に酸化亜鉛結晶粒子の粒成長に影響を及ぼす成分
の量を変化させた第三の非直線抵抗体原料粉末を
充填する方法を採用する場合にも適用し得るもの
である。 Furthermore, in the above embodiment, a case where the second powder is filled outside the first powder has been described, but the present invention is not limited to this, and zinc oxide crystal particles are further filled outside the first and second powders. This method can also be applied when a method of filling a third nonlinear resistor raw material powder in which the amount of a component that affects grain growth is varied is adopted.
更に上記実施例では非直線抵抗体の形状として
円板状のものを用いたが、他の形状のもの例えば
円空円筒状でも、焼結時焼結雰囲気に接する部分
あるいは、セラミツク絶縁物を塗布する部分に上
記実施例の円板の外周縁部と同様に第二の粉末を
充填する方法を採用すれば、本発明の効果を得る
ことができるのは勿論である。 Furthermore, in the above embodiments, a disc-shaped nonlinear resistor was used, but other shapes, such as a hollow cylinder, can also be used, or the part that comes into contact with the sintering atmosphere during sintering or coated with a ceramic insulator can be used. Of course, the effects of the present invention can be obtained by filling the portion with the second powder in the same manner as the outer peripheral edge of the disc in the above embodiment.
第１図、第２図は夫々本発明方法を説明する説
明図、第３図は本発明の製造方法の効果を示す曲
線図である。
１……円筒状金型、２……円盤状鉄板、３……
圧縮成形金型、４……円筒状容器、５……第一の
非直線抵抗体原料粉末、６……第二の非直線抵抗
体原料粉末、７……加圧部材。
FIGS. 1 and 2 are explanatory diagrams for explaining the method of the present invention, respectively, and FIG. 3 is a curve diagram showing the effects of the manufacturing method of the present invention. 1... Cylindrical mold, 2... Disc-shaped iron plate, 3...
Compression mold, 4... Cylindrical container, 5... First non-linear resistor raw material powder, 6... Second non-linear resistor raw material powder, 7... Pressure member.
Claims (1)
くとも一種の金属酸化物を含む金属酸化物非直線
抵抗体の製造方法において、第一の非直線抵抗体
原料粉末と、その周側面にこの第一の非直線抵抗
体原料粉末の添加成分中焼結時に酸化亜鉛結晶粒
子の粒成長を促進する成分の量を増した組成を持
つ第二の非直線抵抗体原料粉末とを金型に充填
し、添加成分の組成比の異なる上記第一及び第二
の非直線抵抗体原料粉末を同時形成し、乾燥した
後に1000〜1500℃の温度で焼結することを特徴と
する金属酸化物非直線抵抗体の製造方法。 ２ 酸化亜鉛を主成分とし、添加成分として少な
くとも一種の金属酸化物を含む金属酸化物非直線
抵抗体の製造方法において、第一の非直線抵抗体
原料粉末と、その周側面にこの第一の非直線抵抗
体原料粉末の添加成分中焼結時に酸化亜鉛結晶粒
子の粒成長を抑制する成分の量を減らした組成を
持つ第二の非直線抵抗体原料粉末とを金型に充填
し、添加成分の組成比の異なる上記第一及び第二
の非直線抵抗体原料粉末を同時形成し、乾燥した
後に1000〜1500℃の温度で焼結することを特徴と
する金属酸化物非直線抵抗体の製造方法。[Claims] 1. A method for manufacturing a metal oxide nonlinear resistor containing zinc oxide as a main component and at least one metal oxide as an additive component, comprising: a first nonlinear resistor raw material powder; A second non-linear resistor raw material powder having a composition with an increased amount of a component that promotes grain growth of zinc oxide crystal grains during sintering among the additive components of this first non-linear resistor raw material powder on the side. Metal oxidation characterized by filling a mold, simultaneously forming the above-mentioned first and second nonlinear resistor raw material powders having different composition ratios of additive components, drying, and then sintering at a temperature of 1000 to 1500 ° C. A method for manufacturing a nonlinear resistor. 2. A method for manufacturing a metal oxide nonlinear resistor containing zinc oxide as a main component and at least one metal oxide as an additive component, including a first nonlinear resistor raw material powder, and a first nonlinear resistor powder on the peripheral surface thereof. A second non-linear resistor raw material powder having a composition in which the amount of a component that suppresses grain growth of zinc oxide crystal particles during sintering is reduced among the additive components of the non-linear resistor raw material powder is filled into a mold and added. A metal oxide nonlinear resistor characterized in that the first and second nonlinear resistor raw material powders having different composition ratios of components are simultaneously formed, dried, and then sintered at a temperature of 1000 to 1500°C. Production method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP55131563A JPS5756901A (en) | 1980-09-24 | 1980-09-24 | Method of producing metal oxide nonlinear resistor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP55131563A JPS5756901A (en) | 1980-09-24 | 1980-09-24 | Method of producing metal oxide nonlinear resistor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5756901A JPS5756901A (en) | 1982-04-05 |
| JPS6235244B2 true JPS6235244B2 (en) | 1987-07-31 |
Family
ID=15060984
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP55131563A Granted JPS5756901A (en) | 1980-09-24 | 1980-09-24 | Method of producing metal oxide nonlinear resistor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5756901A (en) |
-
1980
- 1980-09-24 JP JP55131563A patent/JPS5756901A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5756901A (en) | 1982-04-05 |
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