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US 2,000,307 A · Inventors: OSDEL WILLIAM J VAN
Overview
3 drawing sheets
Every sheet is in the USPTO PDF.
Open the USPTO PDFRead 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 7, 1935. A patent granted before 1976 lasted at most 17 years from grant, so its term ended by May 7, 1952.
- We check US rights only. Old patents can still inspire new ones: improvements may be patentable.
FiledJuly 21, 1931
GrantedMay 7, 1935
Term endedMay 7, 1952
Application number—
Classification (CPC)G04B45/0053
Length7 pages
Sources & verification
Official USPTO records
Cross-check elsewhere
Everything on this page comes from the USPTO record linked above.