Expired, full termArchiveSolo inventor
Machine for forming openings in piping
US 1,813,152 A · Inventors: ENGHAUSER WINFORD L
Overview
The published document from the USPTO: abstract, claims, description and drawings. Open it full size
Read the whole patent
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 July 7, 1931. A patent granted before 1976 lasted at most 17 years from grant, so its term ended by July 7, 1948.
- We check US rights only. Old patents can still inspire new ones: improvements may be patentable.
FiledFebruary 20, 1929
GrantedJuly 7, 1931
Term endedJuly 7, 1948
Application number—
Classification (CPC)B21D28/28 +2 more
Length11 pages
Timeline
Timeline From USPTO dates
Sources & verification
Official USPTO records
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Everything on this page comes from the USPTO record linked above.