Inventor

GRISSINGER GLEN S

US3 patents

Patents

3 patents

US4865489ASep 12, 1989

Mine roof anchor having adjustable resin retaining washer

JENNMAR CORP26 citations91

US5082399AJan 21, 1992

Mine roof anchor having adjustable resin retaining washer and expansion shell assembly with friction reducing means

JENNMAR CORP32 citations90

US5181800AJan 26, 1993

Mine roof anchor having adjustable resin retaining washer

JENNMAR CORP19 citations72