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US3676925A Expired / Lapsed US ⏱️ 0.0 years remaining

Method for making molded carbon composition resistors

Assignee: Panasonic Holdings Corp
•
Filing: 1970-07-28
•
Granted: 1972-07-18
•
Expires: 1990-07-28
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Abstract

Abstract A method of making a molded carbon composition resistor. A core mixture is prepared from a finely divided carbon black or graphite powder and silica powder in a resin at an elevated temperature for giving it the proper plasticity, and the mixture is cooled and crushed into granules. A sleeve mixture is prepared from silica powder in a resin at an elevated temperature for giving it the proper plasticity, and the sleeve mixture is cooled and crushed into granules. The core mixture is formed into an inner core and the sleeve mixture is formed into a sleeve around the inner core. Electrodes are inserted into the ends of the inner core. The method is improved in that prior to the steps of mixing it with the other materials, the silica powder for either the core mixture or the sleeve mixture, or both, is heated to a temperature of from 700 to 1500* C.

Inventors

  • 👤 Kunio Sato
  • 👤 Kanji Sugihara
  • 👤 Takashi Wakabayashi
  • 👤 Tomio Ishida

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 19:59
CPC Classifications
H; H01; H01C; H01C7/00; H01C7/001; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49082; Y10T29/49087; Y10T29/49098

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 23 words
The improvement as claimed in claim 1 in which said silica powder is heated for a period of from 3 to 10 hours.
Claim 2
Dependent Claim 23 words
The improvement as claimed in claim 1 in which the silica powder for both the core mixture and the sleeve mixture is heated.

References Cited (Backward Citations)

US2903666A Cited
US3037266A Cited
US3013240A Cited
US3382574A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1975-07-18 1976-01-17 1976-07-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1979-07-18 1980-01-17 1980-07-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1983-07-18 1984-01-17 1984-07-18 $7700.00 Window Closed / Lapsed

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