Robert Warthmann — 2 Patents | Patent Leaderboard

Robert Warthmann has been granted 2 US patents. The first was granted in 1983 and the most recent in September 1991. Robert Warthmann ranks #1,709,992 of 4,157,543 US inventors in our database (top 41.1%). Patent records list Robert Warthmann in Volketswil, CH.

Issued Patents All Time

Showing 1–2 of 2 patents

Patent #	Title	Co-Inventors	Date
5051024	Sliding closures for roadway expansion joints	—	1991-09-24
4401497	Method and apparatus for butt welding of plastic pipes of large diameter	—	1983-08-30

Robert Warthmann — 2 Patents

Issued Patents All Time

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