US3838378A - Voltage-nonlinear resistors - Google Patents
Voltage-nonlinear resistors Download PDFInfo
- Publication number
- US3838378A US3838378A US00382645A US38264573A US3838378A US 3838378 A US3838378 A US 3838378A US 00382645 A US00382645 A US 00382645A US 38264573 A US38264573 A US 38264573A US 3838378 A US3838378 A US 3838378A
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- US
- United States
- Prior art keywords
- mole percent
- oxide
- voltage
- sintered body
- value
- 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 - Lifetime
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Classifications
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01C—RESISTORS
- H01C7/00—Non-adjustable resistors formed as one or more layers or coatings; Non-adjustable resistors made from powdered conducting material or powdered semi-conducting material with or without insulating material
- H01C7/10—Non-adjustable resistors formed as one or more layers or coatings; Non-adjustable resistors made from powdered conducting material or powdered semi-conducting material with or without insulating material voltage responsive, i.e. varistors
- H01C7/105—Varistor cores
- H01C7/108—Metal oxide
- H01C7/112—ZnO type
Definitions
- V and V are the voltages at given currents l and 1 respectively.
- the desired value of C depends upon the kind of application to which the resistor is to be put. lt is ordinarily desirable that the value of n be as large as possible since this exponent determines the extent to which the resistors depart from ohmic characteristics.
- the n-value defined by l l V, and V as shown in equation (2) is expressed by n to distinguish it from the n-value calculated by other currents or voltages.
- Nonlinear resistors comprising sintered bodies of zinc oxide with or without additives and non-ohmic electrode applied thereto, have already been disclosed as seen in U.S. Pat. Nos. 3,496,512, 3,570,002 and 3,503,029.
- the nonlinearity of such varistors is attributed to the interface between the sintered body ofzinc oxide with or without additives and the silver paint electrode and is controlled mainly by changing the compositions of said sintered body and silver paint electrode. Therefore, it is not easy to control the C- value over a wide range after the sintered body is prepared.
- varistors comprising germanium or silicon p-n junction diodes
- the silicon carbide varistors have nonlinearity due to the contact between the individual grains of silicon carbide bonded together by a ceramic binding material, i.e., to the bulk, and the C-value is controlled by changing dimension in the direction in which the current flows through the varistors.
- the silicon carbide varistors have high surge resistance which is suitable for characteristic elements of lightning arresters. The characteristic elements are used usually by connecting in series with discharging gaps and determine the level of the discharging voltage and the follow current.
- the silicon carbide varistors however, have a relatively low n-value ranging from 3 to 7 which results in poor suppression of lightning surge or increase in the follow current.
- Another defect of the arrester including the discharging gaps as its components is not to respond instantaneously surge voltage having very short rise time such as below lps. It is desirable for the arrester to suppress the lightning surge and the follow current to as low a level as possible and to respond to surge voltage instantaneously.
- voltagenonlinear resistors of bulk type comprising a sintered body of zinc oxide with additives comprising bismuth oxide and antimony oxide and/or chromium oxide, as seen in US. Pat. No. 3,663,458.
- These zinc oxide varistors of bulk type are controllable in a C-value by changing the distance between electrodes and have an excellent nonlinear property With an n-value more than 10 in a region of current below than l0A/cm For a current more than l0A/cm however, the n-value goes down to a value below than llt).
- the power dissipation for surge energy shows a relatively low value compared with that of the conventional silicon carbide arrester, so that the change rate of C-value exceeds 20 percent after two standard lightning surges of 4Xl0us wave form in a peak current of 1,500A/cm are applied to said zinc oxide varistor of the bulk type.
- Another zinc oxide varistor of bulk type which contains as an additive cerium fluoride as disclosed in the co-pending application Ser. No. 29416 filed in Apr. 17, l970.
- This varistor shows an excellent nonlinear property, but an essentially weak point as an arrester element is its weakness with respect to surge pulse. The nonlinear property of the varistor deteriorates easily even for l00A/cm of surge pulse.
- An object of the present invention is to provide a voltage-nonlinear resistor having nonlinearity due to the bulk thereof and being characterized by a high n value even in a range of current more than l0A/cm
- Another object of the present invention is to provide a voltage-nonlinear resistor having high power dissipation for surge energy.
- Another object of the present invention is to provide an arrester characterized by high suppression for lightning surge and low follow current.
- FIG. 1 is a partial cross-sectional view through a voltage-nonlinear resistor in accordance with the invention and FIG. 2 and FIG. 3 partial cross-sectional views through an arrester in accordance with the invention.
- reference character 10 designates, as a whole, a voltage-nonlinear resistor comprising, as its active element, a sintered body having a pair of electrodes 2 and 3 applied to opposite surfaces thereof.
- Said sintered body 1 is prepared in a manner hereinafter set forth.
- Wire leads 5 and 6 are attached conductively to the electrodes 2 and 3, respectively, by a connection means 4 such as solder or the like.
- a voltage-nonlinear resistor comprises a sintered body of a composition comprising, as an additive, 0.l to 3.0 mole percent of bismuth oxide (Bi O 0.05 to 3.0 mole percent of antimony oxide (Sb O and 0.1 to 3.0 mole percent of cerium fluoride (CeF and the remainder of zinc oxide (ZnO) as a main constituent, and electrodes applied to opposite surfaces of said sintered body.
- Bi O bismuth oxide
- Sb O antimony oxide
- CeF cerium fluoride
- ZnO zinc oxide
- Such a voltagenonlinear resistor has non-ohmic resistance due to the bulk itself. Therefore, its C-value can be changed without impairing the n-value by changing the distance between said opposite surfaces.
- said resistor has high n-value in a region of current more than lOA/cm and high stability for surge pulses.
- the higher n-value in a region of current more than lA/cm can be obtained when said sintered body further includes one member selected from the group consisting of0.l to 3.0 mole percent of cobalt oxide (C00) and 0.1 to 3.0 mole percent of manganese oxide (MnO).
- C00 cobalt oxide
- MnO manganese oxide
- the higher nvalue in a region of current more than l0A/cm and the higher stability for surge pulses can be obtained when said sintered body comprises, as a main constituent, zinc oxide (ZnO) and, as an additive 0.1 to 3.0 mole percent of bismuth oxide (Bi O- 0.05 to 3.0 mole percent of antimony oxide (Sb O 0.1 to 3.0 mole percent of cerium fluoride (CeF 0.1 to 3.0 mole percent of cobalt oxide (CoO), 0.1 to 3.0 mole percent of manganese oxide (MnO) and one member selected from the group consisting of 0.05 to 3.0 mole percent of chromium oxide (Cr O 0.1 to 3.0 mole percent of tin oxide (SnO and 0.1 to 10.0 mole percent of silicon dioxide (SiO
- the resistor is remarkably improved in the n-value in a region of current more than l0A/cm and the stability for surge pulse when said sintered body
- the present invention when at least one voltage-nonlinear resistor consisting essentially of a sintered body of 99.4 to 72.0 mole percent of zinc oxide (ZnO), 0.1 to 3.0 mole percent of bismuth oxide (Bi O 0.05 to 3.0 mole percent of antimony oxide (Sb O 0.1 to 3.0 mole percent of cerium fluoride (CeF 0.1 to 3.0 mole percent of cobalt oxide (C00), 0.1 to 3.0 mole percent of manganese oxide (MnO), 0.05 to 3.0 mole percent of chromium oxide (Cr O and 0.1 to 10.0 mole percent of silicon dioxide (SiO and electrodes applied to opposite surfaces of said sintered body are applied as a characteristic element to an arrester, the resultant arrester is further lowered in the follow current and is further improved in the suppression and power dissipation for lightning surges.
- ZnO zinc oxide
- Ba O 0.05 to 3.0 mole percent of antimony oxide
- Sb O 0.1 to 3.0 mole percent
- the sintered body 1 can be prepared by a per se well known ceramic technique.
- the starting materials in the compositions in the foregoing description are mixed in a wet mill so as to produce homogeneous mixtures.
- the mixtures are dried and pressed in a mold into desired shapes at a pressure from 50 I(g./cm to 500 Kg./cm
- the pressed bodies are sintered in air at l,00O to 1,450C for l to 10 hours, and then furnacecooled to room temperature (about 15C to about 30C).
- the mixtures can be preliminarily calcined at 700 to l,000C and pulverized for easy fabrication in the subsequent pressing step.
- the mixture to be pressed can be admixed with a suitable binder such as water, polyvinyl alcohol, etc. It is advantageous that the sintered body be lapped at the opposite surfaces by abrasive powder such as silicon carbide in a particle size of 50p. in mean diameter to 10a in mean diameter.
- abrasive powder such as silicon carbide in a particle size of 50p. in mean diameter to 10a in mean diameter.
- the sintered bodies are provided, at the opposite surfaces thereof with electrodes in any available and suitable method such as silver painting, vacuum evaporation or flame spraying of a metal such as Al, Zn, Sn etc.
- the voltage-nonlinear properties are not practically affected by the kinds of electrodes used, but are affected by the thickness of the sintered bodies. Particularly, the C-value varies in proportion to the thickness of the sintered bodies, while the n-value is almost independent of the thickness. This surely means that the voltage-nonlinear property is due to the bulk itself, but not to the electrodes.
- Electrode wires can be attached to the electrodes in a per se conventional manner by using conventional solder. It is convenient to employ a conductive adhesive comprising silver powder and resin in an organic solvent in order to connect the lead wires to the electrodes.
- Voltage-nonlinear resistors according to this invention have a high stability to temperature and for the surge test, which is carried out by applying lightning surge determined by the J EC (Japanese Electrotechnical Committee)-l56 Standard. The n-value and C-value do not change remarkably after heating cycles and surge test. It is advantageous for achievement of a high stability to humidity and high surges that the resultant voltagenonlinearresistors are embedded in a humidity proof resin such as epoxy resin and phenol resin in a per se well known manner.
- FIG. 2 is the cross-sectional view of an arrester wherein reference character 20 designates, as a whole, an arrester comprising, one or more voltage-nonlinear resistors according to this invention 11 as a characteristic element are connected in series with one or more discharging gaps l2, spring 13 and line terminals 14 and 15. Said arrester elements are enveloped into wetprocess porcelain 16. Said arrester is kept to a level below luA in follow current and to a level higher than 2,000A/cm in surge dissipation.
- FIG. 20 designates, as a whole, an arrester comprising, one or more voltage-nonlinear resistors according to this invention 11 as a characteristic element are connected in series with one or more discharging gaps l2, spring 13 and line terminals 14 and 15. Said arrester elements are enveloped into wetprocess porcelain 16. Said arrester is kept to a level below luA in follow current and to a level higher than 2,000A/cm in surge dissipation.
- FIG. 20 design
- FIG. 3 is the crosssectional view of another arrester wherein reference character 30 designates, as a whole, an arrester comprising at least one voltage-nonlinear resistor according to this invention.
- reference characters identical to those of FIG. 2 have been employed to designate like elements.
- the arrester of FIG. 3 is characterized, in its construction, as without a discharging gap and, in its electrical properties, as having a time shorter than 0.1us for high surges having very sharp rise, in addition to its excellent properties, in follow current and surge dissipation.
- Presently preferred illustrative embodiments of the invention are as follows.
- Example 1 A starting material composed of 98.0 mole percent of zinc oxide, 0.5 mole percent of bismuth oxide, 1.0 mole percent of antimony oxide, and 0.5 mole percent of cerium fluoride is mixed in a wet mill for 24 hours. The mixture is dried and pressed in a mold into discs of 40mm in diameter and mm in thickness at a pressure of 250Kg/cm The pressed bodies are sintered in air at the condition shown in Table 1, and then furnace-cooled to room temperature. The sintered body is lapped at the opposite surfaces thereof into the thickness shown in Table 1 by silicon carbide abrasive in particle size of p. in mean diameter. The opposite surfaces of the sintered body are provided with a spray metallized film of aluminum in a per se well known technique.
- Zinc oxide incorporated with bismuth oxide, antimony oxide, and cerium fluoride in the composition of Table 2 is fabricated into the voltage-nonlinear resistors by the same process as that of Example 1.
- the thickness is 20mm.
- the resulting electrical properties are shown in Table 2, in which the values of n, and n are the n-values defined between 0. lmA and lmA, and
- the impulse test is carried out by applying 2 impulses of 4 l0p.s, 10,000A. It can be easily understood that the combined addition of bismuth oxide, antimony oxide, and cerium fluoride as additives show the high n-value and small change rates.
- Table 1 EXAMPLE 3 Zinc oxide and additives of Table 3 are fabricated Thickness C Simcring into the voltage-nonlinear resistors by the same process (mm) (at lmA) 0.l-1mA Condition as that of Example 1.
- the electrical properties of the resulting resistors are shown in Table 3.
- SHrs rates of C and n values after the impulse test are carried 15 1345 14 1200ZC.
- tai o Zinc oxide and additives of Table 4 are fabricated C into the voltage-nonlinear resistors by the same process as Example 1.
- the electrical characteristics of resulting resistors are shown in Table 4. It will be easily understood that the further addition of tin oxide, chromium oxide, silicon dioxide or chromium oxide and silicon m f 30 i dioxide results in the higher n-value and smaller change rates than those of Example 3.
- the change rates of C and n values after the impulse test are carried out by the same method as that of Example 2 are also shown in Table 4.
- EXAMPLE 6 The voltage-nonlinear resistors according to Example 2, 3 and 4 are employed in the arrester construction shown in FIG. 2 by series connection of 3 pieces of resistor and 1 discharging gap. The C-value of said total pieces of voltage-nonlinear resistor is about 7,000V.
- the impulse test are carried out by applying 2 impulses of 4Xl0us, 1,500A/cm superposed on AC 3000V.
- the follow current of the arrester shows a value lower than l tA as shown in Table 6 and the change rates of electrical properties after the test show same results as the impulse test of Example 2, 3 and 4.
- EXAMPLE 7 The voltage-nonlinear resistors according to Examples 2, 3 and 4 are employed in the arrester construction shown in FIG. 3 by series connection of 3 pieces of resistor. The value of C at said total pieces of voltage-nonlinear resistor is about 7,000V.
- the impulse tests are carried out by the same method as that of Example 6. The follow current shows a value lower than luA as shown in Table 6 and the change rates of electrical properties after testing show the same results as that of the impulse test in Examples 2, 3 and 4.
- Another impulse test is carried out by applying an impulse having the value of 0.0lus in rise time. The rise time of current flowing through said arrester is lower than 0.05; .5.
- a voltage-nonlinear resistor consisting essentially of a sintered body of a composition comprising as a main constituent, zinc oxide (ZnO) and, as an additive, 0.1 to 3.0 mole percent of bismuth oxide (Bi O 0.05 to 3.0 mole percent of antimony oxide (Sb O and 0.1 to 3.0 mole percent of cerium fluoride (CeF and electrodes applied to opposite surfaces of said sintered body.
- C00 cobalt oxide
- MnO manganese oxide
- An arrester comprising at least one voltagenonlinear resistor of claim 1 as a characteristic element.
- An arrester comprising at least one voltagenonlinear resistor of claim 4 as a characteristic element.
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- Engineering & Computer Science (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Compositions Of Oxide Ceramics (AREA)
- Thermistors And Varistors (AREA)
Applications Claiming Priority (7)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP47075328A JPS5146272B2 (de) | 1972-07-26 | 1972-07-26 | |
JP47075330A JPS5146274B2 (de) | 1972-07-26 | 1972-07-26 | |
JP47075332A JPS5146276B2 (de) | 1972-07-26 | 1972-07-26 | |
JP47075327A JPS5146271B2 (de) | 1972-07-26 | 1972-07-26 | |
JP47075326A JPS5146270B2 (de) | 1972-07-26 | 1972-07-26 | |
JP47075329A JPS5146273B2 (de) | 1972-07-26 | 1972-07-26 | |
JP47075331A JPS5146275B2 (de) | 1972-07-26 | 1972-07-26 |
Publications (1)
Publication Number | Publication Date |
---|---|
US3838378A true US3838378A (en) | 1974-09-24 |
Family
ID=27565226
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US00382645A Expired - Lifetime US3838378A (en) | 1972-07-26 | 1973-07-26 | Voltage-nonlinear resistors |
Country Status (7)
Country | Link |
---|---|
US (1) | US3838378A (de) |
CA (1) | CA986235A (de) |
DE (1) | DE2338355C3 (de) |
FR (1) | FR2194026B1 (de) |
GB (1) | GB1403291A (de) |
IT (1) | IT989985B (de) |
NL (1) | NL181959C (de) |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2651274A1 (de) * | 1975-11-12 | 1977-05-26 | Westinghouse Electric Corp | Verfahren zur herstellung eines widerstandskoerpers |
US4111852A (en) * | 1976-12-30 | 1978-09-05 | Westinghouse Electric Corp. | Pre-glassing method of producing homogeneous sintered zno non-linear resistors |
DE2853134A1 (de) * | 1977-12-09 | 1979-06-13 | Matsushita Electric Ind Co Ltd | Keramikvaristor |
US4326232A (en) * | 1979-04-16 | 1982-04-20 | Tokyo Shibaura Denki Kabushiki Kaisha | Lightning arrester |
US5854586A (en) * | 1997-09-17 | 1998-12-29 | Lockheed Martin Energy Research Corporation | Rare earth doped zinc oxide varistors |
US20130119324A1 (en) * | 2010-07-30 | 2013-05-16 | Samsung Display Co., Ltd. | Oxide for semiconductor layer of thin-film transistor, sputtering target, and thin-film transistor |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3508030A1 (de) * | 1985-02-07 | 1986-08-07 | BBC Aktiengesellschaft Brown, Boveri & Cie., Baden, Aargau | Verfahren zur herstellung eines ueberspannungsableiters unter verwendung eines aktiven widerstandskoerpers aus einem spannungsabhaengigen widerstandsmaterial auf zno-basis und danach hergestellter ueberspannungsableiter |
FR2881134B1 (fr) | 2005-01-24 | 2007-04-20 | Areva T & D Sa | Procede de preparation de ceramiques semi-conductrices constituees d'oxydes de metaux, notamment d'oxyde d'etain en particulier pour les varistances |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3611073A (en) * | 1968-12-02 | 1971-10-05 | Matsushita Electric Ind Co Ltd | Diode comprising zinc oxide doped with gallium oxide used as a voltage variable resistor |
US3632528A (en) * | 1968-10-22 | 1972-01-04 | Matsushita Electric Ind Co Ltd | Lead-modified zinc oxide voltage variable resistor |
US3658725A (en) * | 1970-07-24 | 1972-04-25 | Matsushita Electric Ind Co Ltd | Nonlinear resistor and nonlinear resistor composition |
US3778743A (en) * | 1973-02-23 | 1973-12-11 | Matsushita Electric Ind Co Ltd | Voltage-nonlinear resistors |
-
1973
- 1973-07-24 IT IT51615/73A patent/IT989985B/it active
- 1973-07-24 CA CA177,198A patent/CA986235A/en not_active Expired
- 1973-07-25 NL NLAANVRAGE7310361,A patent/NL181959C/xx not_active IP Right Cessation
- 1973-07-25 FR FR7327260A patent/FR2194026B1/fr not_active Expired
- 1973-07-25 DE DE2338355A patent/DE2338355C3/de not_active Expired
- 1973-07-26 US US00382645A patent/US3838378A/en not_active Expired - Lifetime
- 1973-07-26 GB GB3573473A patent/GB1403291A/en not_active Expired
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3632528A (en) * | 1968-10-22 | 1972-01-04 | Matsushita Electric Ind Co Ltd | Lead-modified zinc oxide voltage variable resistor |
US3611073A (en) * | 1968-12-02 | 1971-10-05 | Matsushita Electric Ind Co Ltd | Diode comprising zinc oxide doped with gallium oxide used as a voltage variable resistor |
US3658725A (en) * | 1970-07-24 | 1972-04-25 | Matsushita Electric Ind Co Ltd | Nonlinear resistor and nonlinear resistor composition |
US3778743A (en) * | 1973-02-23 | 1973-12-11 | Matsushita Electric Ind Co Ltd | Voltage-nonlinear resistors |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2651274A1 (de) * | 1975-11-12 | 1977-05-26 | Westinghouse Electric Corp | Verfahren zur herstellung eines widerstandskoerpers |
US4111852A (en) * | 1976-12-30 | 1978-09-05 | Westinghouse Electric Corp. | Pre-glassing method of producing homogeneous sintered zno non-linear resistors |
DE2853134A1 (de) * | 1977-12-09 | 1979-06-13 | Matsushita Electric Ind Co Ltd | Keramikvaristor |
US4326232A (en) * | 1979-04-16 | 1982-04-20 | Tokyo Shibaura Denki Kabushiki Kaisha | Lightning arrester |
US5854586A (en) * | 1997-09-17 | 1998-12-29 | Lockheed Martin Energy Research Corporation | Rare earth doped zinc oxide varistors |
US20130119324A1 (en) * | 2010-07-30 | 2013-05-16 | Samsung Display Co., Ltd. | Oxide for semiconductor layer of thin-film transistor, sputtering target, and thin-film transistor |
US9299474B2 (en) * | 2010-07-30 | 2016-03-29 | Samsung Display Co., Ltd. | Oxide for semiconductor layer of thin-film transistor, sputtering target, and thin-film transistor |
Also Published As
Publication number | Publication date |
---|---|
FR2194026B1 (de) | 1977-05-13 |
FR2194026A1 (de) | 1974-02-22 |
IT989985B (it) | 1975-06-10 |
DE2338355B2 (de) | 1978-08-24 |
GB1403291A (en) | 1975-08-28 |
CA986235A (en) | 1976-03-23 |
NL7310361A (nl) | 1974-01-29 |
NL181959C (nl) | 1987-12-01 |
DE2338355A1 (de) | 1974-02-21 |
DE2338355C3 (de) | 1979-04-26 |
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