JPH03159201A - Oxide resistor - Google Patents
Oxide resistorInfo
- Publication number
- JPH03159201A JPH03159201A JP1299080A JP29908089A JPH03159201A JP H03159201 A JPH03159201 A JP H03159201A JP 1299080 A JP1299080 A JP 1299080A JP 29908089 A JP29908089 A JP 29908089A JP H03159201 A JPH03159201 A JP H03159201A
- Authority
- JP
- Japan
- Prior art keywords
- group
- resistor
- nbo
- nbo2
- oxide
- 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.)
- Pending
Links
- 239000010955 niobium Substances 0.000 claims abstract description 9
- GUCVJGMIXFAOAE-UHFFFAOYSA-N niobium atom Chemical compound [Nb] GUCVJGMIXFAOAE-UHFFFAOYSA-N 0.000 claims abstract description 9
- 230000000737 periodic effect Effects 0.000 claims abstract description 8
- 239000002131 composite material Substances 0.000 claims abstract description 5
- 229910052758 niobium Inorganic materials 0.000 claims abstract description 5
- ZKATWMILCYLAPD-UHFFFAOYSA-N niobium pentoxide Chemical compound O=[Nb](=O)O[Nb](=O)=O ZKATWMILCYLAPD-UHFFFAOYSA-N 0.000 abstract description 10
- HFLAMWCKUFHSAZ-UHFFFAOYSA-N niobium dioxide Inorganic materials O=[Nb]=O HFLAMWCKUFHSAZ-UHFFFAOYSA-N 0.000 abstract description 8
- 238000005245 sintering Methods 0.000 abstract description 8
- 238000000034 method Methods 0.000 abstract description 5
- 150000001875 compounds Chemical class 0.000 abstract description 3
- 239000000843 powder Substances 0.000 description 17
- 239000002994 raw material Substances 0.000 description 7
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 description 4
- 230000007423 decrease Effects 0.000 description 4
- 239000004927 clay Substances 0.000 description 3
- 230000002159 abnormal effect Effects 0.000 description 2
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 2
- 229910000019 calcium carbonate Inorganic materials 0.000 description 2
- 235000010216 calcium carbonate Nutrition 0.000 description 2
- 238000000465 moulding Methods 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 239000002002 slurry Substances 0.000 description 2
- 238000007751 thermal spraying Methods 0.000 description 2
- RUDFQVOCFDJEEF-UHFFFAOYSA-N yttrium(III) oxide Inorganic materials [O-2].[O-2].[O-2].[Y+3].[Y+3] RUDFQVOCFDJEEF-UHFFFAOYSA-N 0.000 description 2
- 229910011255 B2O3 Inorganic materials 0.000 description 1
- -1 C eO2 Inorganic materials 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 229910004742 Na2 O Inorganic materials 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 239000005388 borosilicate glass Substances 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 229910052593 corundum Inorganic materials 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 239000002241 glass-ceramic Substances 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 230000035939 shock Effects 0.000 description 1
- 229910001845 yogo sapphire Inorganic materials 0.000 description 1
Landscapes
- Thermistors And Varistors (AREA)
Abstract
Description
【発明の詳細な説明】
［発明の目的］
（産業上の利用分野）
本発明は酸化物抵抗体に係わり、特に、遮断器等の開閉
サージの吸収に好適な酸化物抵抗体に関する。DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to an oxide resistor, and particularly to an oxide resistor suitable for absorbing switching surges of circuit breakers and the like.
（従来の技術）
従来から、電力用遮断器の遮断接点に対して並列に抵抗
体を接続して、開閉時に発生する異常電圧を抑制したり
、遮断容量を増加させる技術は、周知である。この遮断
器用抵抗体としては、アルミナ−炭素−粘土系の焼結体
からなる抵抗体が知られている。この抵抗体は、抵抗値
が約５００Ω・国、抵抗温度係数が一９Ｘ１０−２、熱
容量が２Ｊ／ｃｃ−にであって、遮断器の開閉サージ耐
量が３００Ｊ／ｃｃの特性を有する。しかし、この抵抗
体は、炭素を加えたアルミナ粘土を不活性雰囲気中で焼
結することにより製造され、含まれる炭素の含有量を制
御することにより、抵抗値を調整している。(Prior Art) Conventionally, a technique is well known in which a resistor is connected in parallel to the breaking contact of a power circuit breaker to suppress abnormal voltage generated during switching and to increase the breaking capacity. As this resistor for a circuit breaker, a resistor made of an alumina-carbon-clay sintered body is known. This resistor has a resistance value of about 500 Ω, a resistance temperature coefficient of 19×10 −2 , a heat capacity of 2 J/cc, and a circuit breaker switching surge withstand capacity of 300 J/cc. However, this resistor is manufactured by sintering carbon-added alumina clay in an inert atmosphere, and the resistance value is adjusted by controlling the carbon content.
このために、この抵抗体は、低密度であり、しかも、単
位体積あたりの熱容量が２Ｊ／ｃｃ−にと小さく、開閉
サージ耐量が十分ではない。For this reason, this resistor has a low density, has a small heat capacity per unit volume of 2 J/cc-, and does not have sufficient switching surge resistance.
ところで、近年の技術開発による遮断器の小型化に伴い
、抵抗器の小型化が求められている。抵抗体を小型化す
るためには、単位体積あたりの熱容量が大きいことが必
要であり、従来の抵抗体の２Ｊ／ｃｃ−にという熱容量
では、不十分である。By the way, as circuit breakers become smaller due to recent technological developments, there is a demand for smaller resistors. In order to miniaturize a resistor, it is necessary to have a large heat capacity per unit volume, and the heat capacity of 2 J/cc- of a conventional resistor is insufficient.
また、このアルミナ−度素−粘土系の焼結体からなる抵
抗体は、電気抵抗の温度係数が負であるために、サージ
電流が流れて抵抗体の温度が上昇するに伴い、電気抵抗
が減少してしまい、遮断器の信頼性上、問題となる。In addition, the temperature coefficient of electrical resistance of this resistor made of alumina-durium-clay-based sintered body is negative, so as a surge current flows and the temperature of the resistor increases, the electrical resistance decreases. This causes a problem in terms of circuit breaker reliability.
（発明が解決しようとする課題）
従来の遮断器用抵抗体は、単位体積あたりの熱容量が小
さいために小型化することができず、しかも、その電気
抵抗の温度係数が負であるために、遮断器の信頼性を損
なう虞がある。(Problems to be Solved by the Invention) Conventional circuit breaker resistors cannot be miniaturized because they have a small heat capacity per unit volume, and furthermore, the temperature coefficient of their electrical resistance is negative, so they are difficult to interrupt. There is a risk of damaging the reliability of the device.
本発明の目的は、単位体積あたりの熱容量が大きく、十
分なサージ耐量を有する酸化物抵抗体を提供することに
ある。An object of the present invention is to provide an oxide resistor having a large heat capacity per unit volume and sufficient surge resistance.
［発明の構成］
（課題を解決するための手段および作用）本発明は、Ｎ
ｂＯ２を主成分とし、ＮｂＯ並びに周期律表のＩａ族、
ＩＩａ族、ＩＩＩａ族または■ｂ族の元素とニオブとの
複合酸化物を含有することを特徴とする酸化物抵抗体で
ある。[Structure of the invention] (Means and effects for solving the problem) The present invention
The main component is bO2, NbO and group Ia of the periodic table,
This is an oxide resistor characterized by containing a composite oxide of a group IIa, group IIIa, or group IIb element and niobium.
本発明の低抗体中に含まれる周期律表のＩａ族、ＩＩＩ
ａ族、ｎｌａ族またはＩＩＩｂ族の元素とニオブとの複
合酸化物としては、ＹＮｂ ０４ 、ＣａＮｂ２Ｏ６、
Ｎａ２ＮｂＯ４、Ｋ６Ｎｂ４４０１１３等を用いること
ができる。Group Ia and III of the periodic table contained in the low antibody of the present invention
Examples of composite oxides of niobium and elements of group A, group NLA, or group IIIb include YNb 04 , CaNb2O6,
Na2NbO4, K6Nb440113, etc. can be used.
本発明の抵抗体においては、その抵抗値を所定の値、好
ましくは１００〜１０００Ω・叩の範囲とするために、
ＮｂＯ□とＮｂＯとの含有割合はＮ ｂ ０２が９０％
以上、ＮｂＯが１０％以下であることが好ましい。Ｎｂ
Ｏの含有量が多くなると抵抗値が小さくなり、ＮｂＯ２
の含有量が少なくなると、同様に抵抗値が小さくなる。In the resistor of the present invention, in order to set the resistance value to a predetermined value, preferably in the range of 100 to 1000 Ω.
The content ratio of NbO□ and NbO is 90% Nb02
As mentioned above, it is preferable that NbO is 10% or less. Nb
As the O content increases, the resistance value decreases, and NbO2
When the content of , the resistance value decreases as well.
また、周規律表のＩａ族、ＩＩａ族、ＩＩＩａ族または
ＩＩＩｂ族の元素の含有量は、元素の原子換算で、ｏ、
ｏｏｔ〜２０重量％であることが好ましい。In addition, the content of elements in group Ia, group IIa, group IIIa, or group IIIb in the periodic table is o,
It is preferable that it is oot~20% by weight.
本発明の抵抗体は、抵抗体中の夫々の粒子間に、粒子よ
りも体積抵抗率が小さいかまたは同程度の粒界相が存在
してもよい。また、焼結体の°粒界に存在する気孔は少
ないことが好ましく、５％以下であることが望ましい。In the resistor of the present invention, a grain boundary phase having a volume resistivity smaller than or equal to that of the particles may exist between each particle in the resistor. Further, it is preferable that the number of pores existing at the grain boundaries of the sintered body is small, and preferably 5% or less.
この様な本発明の抵抗体は、例えば、以下の様に製造さ
れる。Ｎｂ金属粉末とＮｂ２Ｏ５粉末を所定の割合で秤
量し、これに周規律表のＩａ族、ＩＩａ族、ＩＩＩａ族
またはＩＩＩｂ族の元素を含む化合物（例えば、Ｎａ２
Ｏ、ＣａＣＯ３、Ｂ２０３ 、ＭｇＯ，Ｙ２０３ 、Ｃ
ｅＯ２、Ｓｍ２０３ 、Ａｌ２Ｏ３等）を元素の原子換
算で０．００１〜２０重量％の割合で混合した後、ボー
ルミル等で混合粉砕して、原料粉末を得る。この原料粉
末に適当な有機バインダを添加して造粒した後、金型成
形法等により、板状等の所定の形状の成形体を作成する
。この成形体を電気炉等を用いて、Ａｒガス等の不活性
ガス中もしくは真空中で１０００℃〜１４００℃で２〜
２４時間で焼結後、炉冷して、焼結体を得る。この焼結
体の焼結時に、ＮｂとＮｂ２Ｏ５とが反応して、ＮｂＯ
２およびＮｂＯが生成される。また、添加された周規律
表のＩａ族、ＩＩａ族、ＩＩＩａ族またはＩＩＩｂ族の
元素を含む化合物は焼結温度を下げる働きをする。焼結
温度が高くなるとＮｂＯの生成割合が高くなり、得られ
た抵抗体の抵抗値が小さくなる。Such a resistor of the present invention is manufactured, for example, as follows. Nb metal powder and Nb2O5 powder are weighed in a predetermined ratio, and a compound containing an element of Group Ia, Group IIa, Group IIIa, or Group IIIb of the periodic table (for example, Na2
O, CaCO3, B203, MgO, Y203, C
eO2, Sm203, Al2O3, etc.) at a ratio of 0.001 to 20% by weight in terms of elemental atoms, and then mixed and pulverized using a ball mill or the like to obtain a raw material powder. After adding a suitable organic binder to this raw material powder and granulating it, a molded body having a predetermined shape such as a plate shape is created by a molding method or the like. This molded body is heated at 1000°C to 1400°C in an inert gas such as Ar gas or in a vacuum for 2 to 30 minutes using an electric furnace or the like.
After sintering for 24 hours, it is cooled in a furnace to obtain a sintered body. During sintering of this sintered body, Nb and Nb2O5 react and NbO
2 and NbO are produced. Further, the added compound containing an element of group Ia, group IIa, group IIIa, or group IIIb of the periodic table functions to lower the sintering temperature. As the sintering temperature increases, the proportion of NbO produced increases, and the resistance value of the resulting resistor decreases.
得られた焼結体は、その両端面を研削加工等により、平
行度と平面粗度を整えた後、溶射や焼付は法等により、
電極が形成されて抵抗体となる。The obtained sintered body is processed by grinding both end faces to adjust its parallelism and flatness, and then thermal spraying and baking are carried out by methods such as methods.
Electrodes are formed to form a resistor.
この抵抗体は、必要に応じて、側面での沿面放電を防止
するために絶縁性のガラス層やガラスセラミック層が側
面に形成される。An insulating glass layer or glass ceramic layer is formed on the side surface of this resistor, if necessary, in order to prevent creeping discharge on the side surface.
この様な抵抗体は、吸収する異状電圧の大きさに応じて
、所定の枚数を直列に積層圧接して抵抗体ブロックとし
、この抵抗体ブロックを遮断接点と並列に接続して、用
いられる。Depending on the magnitude of the abnormal voltage to be absorbed, a predetermined number of such resistors are laminated and pressure-welded in series to form a resistor block, and this resistor block is connected in parallel with a breaking contact for use.
本発明によれば、ＮｂＯ２を主成分とし、ＮｂＯ並びに
周期律表のＩａ族、ＩＩａ族、ＩＩＩａ族またはＩＩＩ
ｂ族の元素とニオブとの複合酸化物を含有する抵抗体は
、単位体積当たりの熱容量が大きく、耐熱衝撃性に優れ
るため、遮断器の開閉サージ耐量が大きく、しかも、抵
抗値の温度係数が実用上支障のない程度に小さい抵抗体
が得られる。従って、本発明の抵抗体を用いることによ
り、遮断器の小型化が実現できる。さらに、この抵抗体
は、ＮｂＯ２とＮｂＯとの含有割合を調整することによ
り、その抵抗値を１００〜１０００Ω・国の間の任意の
値に設定できる。According to the present invention, the main component is NbO2, and NbO as well as Ia group, IIa group, IIIa group or III group of the periodic table.
A resistor containing a composite oxide of group B elements and niobium has a large heat capacity per unit volume and excellent thermal shock resistance, so it has a large switching surge withstand capacity for circuit breakers and has a low temperature coefficient of resistance. A resistor that is small enough to cause no practical problems can be obtained. Therefore, by using the resistor of the present invention, a circuit breaker can be made smaller. Further, the resistance value of this resistor can be set to an arbitrary value between 100 and 1000 Ω/mm by adjusting the content ratio of NbO2 and NbO.
（実施例） 以下、本発明の実施例について説明する。(Example) Examples of the present invention will be described below.
（実施例１）
原料粉末としてニオブ粉末５２４ｇ 、 Ｎ ｂ ２０
．粉末５００ｇ、ＣａＣＯ３粉末５ｇを用い、この原料
粉末をボールミルで４時間湿式混合した後、５％ＰＶＡ
水溶液を３重量％添加してスラリーとした。このスラリ
ーを１４８ｍｌ１φＸ３２ｍｍの円板状となるように１
０００ｋｇ／ ｃｍ ２の圧力で金型成形して、成形体
とした。この成形体を１気圧のＡｒ雰囲気の電気炉中で
１２５０°Ｃで２時間加熱して焼結した後、炉冷して、
焼結体を得た。この焼結体の側面に、ホウケイ酸ガラス
粉末を塗布した後、焼き付けた。(Example 1) 524 g of niobium powder as raw material powder, N b 20
．． Using 500 g of powder and 5 g of CaCO3 powder, this raw material powder was wet mixed in a ball mill for 4 hours, and then mixed with 5% PVA.
A slurry was prepared by adding 3% by weight of an aqueous solution. Pour this slurry into a 148ml 1φ x 32mm disk.
The molded product was formed by molding at a pressure of 000 kg/cm 2 . This molded body was heated and sintered at 1250°C for 2 hours in an electric furnace with an Ar atmosphere of 1 atm, and then cooled in the furnace.
A sintered body was obtained. After applying borosilicate glass powder to the side surface of this sintered body, it was baked.
この焼結体の両端面を研削加工して、洗浄後、この端面
にアルミ電極を溶射により、形成して、抵抗体を得た。Both end faces of this sintered body were ground, and after cleaning, aluminum electrodes were formed on the end faces by thermal spraying to obtain a resistor.
この抵抗体の抵抗率、抵抗温度係数、開閉サージ耐量を
測定し、その結果を表に示した。The resistivity, temperature coefficient of resistance, and switching surge resistance of this resistor were measured, and the results are shown in the table.
（実施例２）
原料粉末として、ニオブ粉末５２４ｇ 、 Ｎ ｂ ２
０５粉末５００ｇ、Ｎａ２０粉末５ｇを用いて、実施例
１と同様な方法で、実施例１と同様な大きさの抵抗体を
得た。(Example 2) As raw material powder, 524 g of niobium powder, Nb2
A resistor of the same size as in Example 1 was obtained in the same manner as in Example 1 using 500 g of 05 powder and 5 g of Na20 powder.
この抵抗体の抵抗率、抵抗温度係数、開閉サージ耐量を
測定し、その結果を表に示した。The resistivity, temperature coefficient of resistance, and switching surge resistance of this resistor were measured, and the results are shown in the table.
（実施例３）
原料粉末として、ニオブ粉末５２４ｇ、Ｎｂ２Ｏ５粉末
５００ｇ、 Ｙ２０３粉末ｌｏｇを用いて、実施例１と
同様な方法で、実施例１と同様な大きさの抵抗体を得た
。(Example 3) A resistor of the same size as in Example 1 was obtained in the same manner as in Example 1 using 524 g of niobium powder, 500 g of Nb2O5 powder, and log of Y203 powder as raw material powders.
この抵抗体の抵抗率、抵抗温度係数、開閉サージ耐量を
測定し、その結果を表に示した。The resistivity, temperature coefficient of resistance, and switching surge resistance of this resistor were measured, and the results are shown in the table.
（実施例４）
原料粉末として、ニオブ粉末５２４ｇ、、Ｎｂ２Ｏ５粉
末５００ｇ５Ａ ｌ ２０３粉末ｌｏｇ：を用いて、実
施例１と同様な方法で、実施例１と同様な大きさの抵抗
体を得た。(Example 4) A resistor of the same size as in Example 1 was obtained in the same manner as in Example 1 using 524 g of niobium powder and 500 g of Nb2O5 powder as raw material powder.
この抵抗体の抵抗率、抵抗温度係数、開閉サージ耐量を
測定し、その結果を表に示した。The resistivity, temperature coefficient of resistance, and switching surge resistance of this resistor were measured, and the results are shown in the table.
（以下余白） 酸化物抵抗体を提供することができる。(Margin below) An oxide resistor can be provided.
Claims (1)
ａ族、IIａ族、IIIａ族またはIIIｂ族の元素とニオブと
の複合酸化物を含有することを特徴とする酸化物抵抗体
。The main component is NbO_2, NbO and I of the periodic table.
An oxide resistor comprising a composite oxide of a group a, group IIa, group IIIa, or group IIIb element and niobium.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1299080A JPH03159201A (en) | 1989-11-17 | 1989-11-17 | Oxide resistor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1299080A JPH03159201A (en) | 1989-11-17 | 1989-11-17 | Oxide resistor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH03159201A true JPH03159201A (en) | 1991-07-09 |
Family
ID=17867929
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1299080A Pending JPH03159201A (en) | 1989-11-17 | 1989-11-17 | Oxide resistor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH03159201A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7737066B2 (en) * | 2001-05-15 | 2010-06-15 | Showa Denko K.K. | Niobium monoxide powder, niobium monoxide sintered body and capacitor using the sintered body |
-
1989
- 1989-11-17 JP JP1299080A patent/JPH03159201A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7737066B2 (en) * | 2001-05-15 | 2010-06-15 | Showa Denko K.K. | Niobium monoxide powder, niobium monoxide sintered body and capacitor using the sintered body |
| US7986508B2 (en) | 2001-05-15 | 2011-07-26 | Showa Denko K.K. | Niobium monoxide powder, niobium monoxide sintered body and capacitor using the sintered body |
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