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US4319215A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Non-linear resistor and process for producing same
Assignee: Hitachi Ltd
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Filing: 1980-06-26
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Granted: 1982-03-09
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Expires: 2000-06-26
Abstract
Abstract Disclosed is a non-linear resistor of a sintered ZnO ceramics, which has a glass coating having a baking temperature higher than 850 DEG C. but a temperature lower than the sintering temperature of the sintered ZnO ceramics, and has a composition: (a) 30 to 75% by weight of SiO2, (b) 0.3 to 15% by weight of at least B2O3 and PbO, (c) 2 to 30% by weight of Al2O3, (d) less than 30% by weight of an alkaline earth metal oxide, (e) less than 40% by weight of ZnO, (f) less than 25% by weight of TiO2, and (g) less than 5% by weight of an alkali metal oxide. The glass coating baked at a range of 850 DEG C. to 1300 DEG C. provides non-linear resistors having a large non-linear coefficient and a high impulse current resistance as well as a good resistance to an acid and water.
Inventors
- 👤 Takeo Yamazaki
- 👤 Tadahiko Miyoshi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 18:37
CPC Classifications
H; H01; H01C; H01C7/00; H01C7/10; H01C7/102
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
144 words
A non-linear resistor of a sintered body containing zinc oxide as the main ingredient and Bi 2 O 3 as an additional component, comprising the sintered body, a pair of opposite electrodes in electrical contact with the sintered body and an acid-resistant glass coating formed on the exposed surface of said sintered body between said electrodes, wherein said glass coating has a baking temperature of 850° C. or higher, but lower than the sintering temperature for the sintered body and comprises 30 to 75% by weight of SiO 2 , 0.3 to 15% by weight of at least one of B 2 O 3 and PbO, 2 to 30 by weight of Al 2 O 3 , less than 30% by weight of alkaline earth metal oxide, less than 40% by weight of ZnO, and less than 25% by weight of TiO 2 .
Claim 2
Dependent Claim
144 words
A non-linear resistor of a sintered body containing zinc oxide as the main ingredient and Bi 2 O 3 as an additional component, comprising the sintered body, a pair of opposite electrodes in electrical contact with the sintered body and an acid-resistant glass coating formed on the exposed surface of said sintered body between said electrodes, wherein said glass coating has a baking temperature of 850° C. or higher, but lower than the sintering temperature for the sintered body and comprises 30 to 75% by weight of SiO 2 , 0.3 to 15% by weight of at least one of B 2 O 3 and PbO, 2 to 30 by weight of Al 2 O 3 , less than 30% by weight of alkaline earth metal oxide, less than 40% by weight of ZnO, and less than 25% by weight of TiO 2 .
Claim 3
Dependent Claim
56 words
A non-linear resistor according to claim 1, wherein said glass coating comprises 35 to 75% by weight of SiO 2 , 0.5 to 10% by weight of at least one of B 2 O 3 and PbO, 5 to 30% by weight of Al 2 O 3 , and 5 to 40% by weight of ZnO.
Claim 4
Dependent Claim
95 words
A non-linear resistor according to claim 1, wherein said glass coating consists essentially of 35 to 45% by weight of SiO 2 , 15 to 25% by weight of Al 2 O 3 , 1 to 5% by weight of at least one of B 2 O 3 and PbO, 5 to 15% by weight of ZnO, 10 to 15% by weight of TiO 2 , less than 5% by weight of an alkali metal oxide, 2 to 10% by weight of an alkaline earth metal oxide, and a small amount of other metal oxides.
Claim 5
Dependent Claim
41 words
A non-linear resistor according to claim 1, claim 2 or claim 3, wherein a high resistant layer contiguous to the surface of said sintered body comprising Zn 7 Sb 2 O 12 and ZnSiO 4 is formed beneath the glass coating.
Claim 6
Dependent Claim
70 words
A non-linear resistor according to claim 1, claim 2 or claim 3, wherein the sintered body comprises more than 50 molar % of ZnO, 0.01 to 10 molar % of Bi 2 O 3 , and 0.01 to 10 molar % by weight of at least one of MnO 2 , Co 2 O 3 , Cr 2 O 3 , B 2 O 3 , SiO 2 and NiO.
Claim 7
Dependent Claim
28 words
A non-linear resistor according to claim 1, claim 2 or claim 3, wherein said glass coating has been baked at a temperature ranging between 850° and 1300° C.
Claim 8
Dependent Claim
24 words
A non-linear resistor according to claim 1, claim 2 or claim 3, wherein the thickness of the glass coating is more than 20 μm.
Claim 9
Dependent Claim
162 words
A non-linear resistor of a sintered body containing zinc oxide as the main ingredient and Bi 2 O 3 as an additional component, comprising the sintered body, a pair of opposite electrodes in electrical contact with the sintered body, and an acid-resistant glass coating formed on the exposed surface of said sintered body between said electrodes, wherein said glass coating has a baking temperature of 850° C. or higher, but lower than the sintering temperature for the sintered body, and comprises 30 to 75% by weight of SiO 2 . 0.3 to 15% by weight of at least one of B 2 O 3 and PbO, 2 to 30% by weight of Al 2 O 3 , less than 30% by weight of an alkaline earth metal oxide, less than 40% by weight of ZnO, and less than 25% by weight of TiO 2 ; the total amount of SiO 2 and Al 2 O 3 being at least 50% by weight.
Claim 10
Dependent Claim
162 words
A non-linear resistor of a sintered body containing zinc oxide as the main ingredient and Bi 2 O 3 as an additional component, comprising the sintered body, a pair of opposite electrodes in electrical contact with the sintered body, and an acid-resistant glass coating formed on the exposed surface of said sintered body between said electrodes, wherein said glass coating has a baking temperature of 850° C. or higher, but lower than the sintering temperature for the sintered body, and comprises 30 to 75% by weight of SiO 2 . 0.3 to 15% by weight of at least one of B 2 O 3 and PbO, 2 to 30% by weight of Al 2 O 3 , less than 30% by weight of an alkaline earth metal oxide, less than 40% by weight of ZnO, and less than 25% by weight of TiO 2 ; the total amount of SiO 2 and Al 2 O 3 being at least 50% by weight.
Claim 11
Dependent Claim
74 words
A non-linear resistor according to claim 1 or claim 8, wherein said glass coating consists essentially of 35 to 75% by weight SiO 2 , 0.5 to 10% by weight of B 2 O 3 and/or PbO, 5 to 30% by weight of Al 2 O 3 , 5 to 40% by weight of ZnO, less than 30% by weight of an alkaline earth metal oxide and less than 25% of TiO 2 .
Claim 12
Dependent Claim
77 words
A non-linear resistor according to claim 1, claim 8, or claim 9, wherein said sintered body consists essentially of at least 50 molar % of ZnO, 0.01 to 10 molar % of Bi 2 O 3 and 0.01 to 10 molar % by weight of at least one oxide selected from the group consisting of MnO 2 , Co 2 O 3 , Cr 2 O 3 , B 2 O 3 , SiO 2 and NiO.
References Cited (Backward Citations)
JPS5322273A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-03-08 | 1985-09-07 | 1986-03-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-03-08 | 1989-09-07 | 1990-03-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-03-08 | 1993-09-07 | 1994-03-09 | $7700.00 | Window Closed / Lapsed |