DR

Duane D. Robertson

UN Unknown: 2 patents #12,644 of 83,584Top 20%
Overall (All Time): #663,263 of 4,157,543Top 20%
8
Patents All Time

Issued Patents All Time

Patent #TitleCo-InventorsDate
6810587 Combined clamping and cutting tool for plastic pipes 2004-11-02
6370780 Spring-biased cutting tool for plastic pipes Rodney May, Kit N. Robertson 2002-04-16
6318761 Replacement fitting for rigid, plastic pipes 2001-11-20
5487571 Pipe fitting 1996-01-30
4956916 Cutting tool 1990-09-18
4789189 Pipe saddle 1988-12-06
D266736 Cutting tool for flexible plastic conduit 1982-11-02
4336652 Cutting tool for flexible plastic conduit 1982-06-29