Inventor · disambiguated record
Darwin R. Grahl
Also filed as: GRAHL DARWIN R
6 granted patents·129 citations·filing 1974–1979
85Inventor score
Files withPARKER HANNIFIN CORP6
Top patents by PatentIndex Score
6 records- 0179US4059297ATube couplingPARKER HANNIFIN CORP·Filed 1976·Granted Nov 22, 1977·36 cites·1 claims
- 0274US4124235ATube couplingPARKER HANNIFIN CORP·Filed 1977·Granted Nov 7, 1978·30 cites·12 claims
- 0371US4255940ADischarge line filter-dryerPARKER HANNIFIN CORP·Filed 1979·Granted Mar 17, 1981·28 cites·12 claims
- 0452US3937029AMethod and apparatus for charging air conditioners with refrigerant fluidPARKER HANNIFIN CORP·Filed 1974·Granted Feb 10, 1976·12 cites·14 claims
- 0550US4087986AControl valvePARKER HANNIFIN CORP·Filed 1976·Granted May 9, 1978·11 cites·10 claims
- 0645US4026320AValve assembly for panel mountingPARKER HANNIFIN CORP·Filed 1975·Granted May 31, 1977·12 cites·3 claims
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Identity basis: PatentsView inventor disambiguation (2025Q4-odp release). How scoring works →