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Electrical heater for heating a wall of a fluid-carrying member

US 3,548,159 A · Inventors: ELLSTROEM JOHAN RAGNER

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3 drawing sheets

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Listed from its USPTO record in Patent Yard's full-term archive. Its claims, description and drawings are in the USPTO PDF and on Google Patents, and the Claude kit works from them.

Why it's free to use

  • Granted December 15, 1970. A patent granted before 1976 lasted at most 17 years from grant, so its term ended by December 15, 1987.
  • We check US rights only. Old patents can still inspire new ones: improvements may be patentable.
Filed—
GrantedDecember 15, 1970
Term endedDecember 15, 1987
Application number—
Classification (CPC)F25B33/00 +1 more
Length7 pages

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