Heinz Witschi

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Adligenswil, CH

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Patents Grantslast 30 patents

Information Patent Grant
Locking component for securing a cover on a frame
- Patent number 5,110,235
- Issue date May 5, 1992
- Abt, Inc.
- Roland Thomann
- E03 - WATER SUPPLY SEWERAGE
Information Patent Grant
Drainage channel with locking grate
- Patent number RE33439
- Issue date Nov 13, 1990
- Abt, Inc.
- Roland Thomann
- 404 - Road structure, process, or apparatus
Information Patent Grant
Drainage channel with locking grate
- Patent number 4,630,962
- Issue date Dec 23, 1986
- Roland Thomann
- E01 - CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
Information Patent Grant
Drainage channel
- Patent number 4,621,939
- Issue date Nov 11, 1986
- Polydrain, Inc.
- Roland Thomann
- E01 - CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES