US4259657A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Self heat generation type positive characteristic thermistor and manufacturing method thereof
Assignee: Panasonic Holdings Corp
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Filing: 1979-05-10
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Granted: 1981-03-31
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Expires: 1999-05-10
Abstract
Abstract A self heat generation type positive characteristic thermistor and a manufacturing method thereof. The thermistor is made of more than three layers of positive characteristic thermistor element bodies, such that the specific resistance of the layer situated nearer the surface in the direction of element thickness perpendicular to electrodes is higher. According to this invention a positive characteristic thermistor which generates heat instantaneously when a large current is flown therethrough and has excellent thermal shock proof properties can be obtained simply. The thermistor is well suited to mass production and the use of the thermistor can be extended to many fields.
Inventors
- 👤 Kazuo Ishikawa
- 👤 Kazuo Hosaka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 23:42
CPC Classifications
H; H01; H01C; H01C1/00; H01C1/14; H01C1/1406; H01C7/00; H01C7/02; H01C7/022; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49082; Y10T29/49085
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
45 words
A self heat generation type positive characteristic thermistor comprising at least three layers of positive characteristic thermistor element bodies, the specific resistance of said layers being such that the specific resistance of the layers decreasing from the outermost layers to the center of said thermistor.
Claim 2
Dependent Claim
45 words
A self heat generation type positive characteristic thermistor comprising at least three layers of positive characteristic thermistor element bodies, the specific resistance of said layers being such that the specific resistance of the layers decreasing from the outermost layers to the center of said thermistor.
Claim 3
Dependent Claim
28 words
A self heat generation type positive characteristic thermistor according to claim 1, wherein said positive characteristic thermistor element bodies have a barium titanate system as a main constituent.
Claim 4
Independent Claim
52 words
A method of manufacturing a self heat generation type positive characteristic thermistor comprising steps of filling positive characteristic thermistor elements layerwise in at least three layers using the materials of different specific resistances such that the specific resistance of the layers decreasing from the outermost layers to the center of said thermistor.
Claim 5
Independent Claim
52 words
A method of manufacturing a self heat generation type positive characteristic thermistor comprising steps of filling positive characteristic thermistor elements layerwise in at least three layers using the materials of different specific resistances such that the specific resistance of the layers decreasing from the outermost layers to the center of said thermistor.
Claim 6
Dependent Claim
31 words
A method of manufacturing a self heat generation type positive characteristic thermistor according to claim 3, wherein a material with barium titanate as a main constituent is used for said materials.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-03-30 | 1984-09-29 | 1985-03-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-03-30 | 1988-09-29 | 1989-03-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-03-30 | 1992-09-29 | 1993-03-31 | $7700.00 | Window Closed / Lapsed |