Patent Yard Sign in
Expired, full termArchiveSolo inventor

Paper making machinery

US 2,039,780 A · Inventors: DARBY JAMES K

USPTO PDF

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 May 5, 1936. A patent granted before 1976 lasted at most 17 years from grant, so its term ended by May 5, 1953.
  • We check US rights only. Old patents can still inspire new ones: improvements may be patentable.
FiledFebruary 27, 1930
GrantedMay 5, 1936
Term endedMay 5, 1953
Application number—
Classification (CPC)D21F7/001
Length24 pages

Timeline

Timeline From USPTO dates

19311934193719401943194619491952Application filedFeb 27, 1930Patent grantedMay 5, 1936Term endedMay 5, 1953

Sources & verification