Inventor · disambiguated record
Donald F. Engel
Also filed as: ENGEL DONALD · ENGEL DONALD F · ENGEL DONALD FRANCIS · HAROLD SHIRLEY A
36 granted patents·2 pending applications·2,849 citations·filing 1986–2021
98Inventor score
Top patents by PatentIndex Score
38 records- 0199US7396375B2Air filter having fluted filter mediaDONALDSON CO INC·Filed 2003·Granted Jul 8, 2008·237 cites·40 claims
- 0299US5897676AReverse flow air filter arrangement and methodDONALDSON CO INC·Filed 1998·Granted Apr 27, 1999·299 cites·19 claims
- 0399US5613992AReverse flow air filter arrangement and methodDONALDSON CO INC·Filed 1994·Granted Mar 25, 1997·434 cites·19 claims
- 0499US4720292ACylindrical air filter with lightweight housing and radially directed sealDONALDSON CO INC·Filed 1986·Granted Jan 19, 1988·405 cites·10 claims
- 0598US8562707B2Air filter having fluted filter mediaNEPSUND LARRY R·Filed 2012·Granted Oct 22, 2013·56 cites·19 claims
- 0698US7981183B2Filter arrangements; side-entry housings; and methodsDONALDSON CO INC·Filed 2010·Granted Jul 19, 2011·108 cites·20 claims
- 0798US7905936B2Filter arrangements; housing; assemblies; and, methodsDONALDSON CO INC·Filed 2005·Granted Mar 15, 2011·126 cites·6 claims
- 0898US7655074B2Filter arrangements; side-entry housings; and methodsDONALDSON CO INC·Filed 2004·Granted Feb 2, 2010·154 cites·24 claims
- 0998US6322602B2Reverse flow air filter arrangementDONALDSON CO INC·Filed 2001·Granted Nov 27, 2001·118 cites·10 claims
- 1097US9162172B2Air filter having fluted filter mediaDONALDSON CO INC·Filed 2013·Granted Oct 20, 2015·20 cites·37 claims
- 1197US8641795B2Filter arrangements; housing; assemblies; and, methodsDONALDSON CO INC·Filed 2012·Granted Feb 4, 2014·21 cites·11 claims
- 1297US8343245B2Filter arrangements; housings; assemblies; and, methodsDONALDSON CO INC·Filed 2011·Granted Jan 1, 2013·27 cites·22 claims
- 1397US6413289B2Reverse flow air filter arrangementDONALDSON CO INC·Filed 2001·Granted Jul 2, 2002·76 cites·20 claims
- 1496US9283507B2Filter arrangements; housings; assemblies; and, methodsDONALDSON CO INC·Filed 2014·Granted Mar 15, 2016·17 cites·20 claims
- 1596US8206479B2Air filter having fluted filter mediaNEPSUND LARRY R·Filed 2011·Granted Jun 26, 2012·23 cites·13 claims
- 1696US7635403B2Air filter having fluted filter mediaDONALDSON CO INC·Filed 2008·Granted Dec 22, 2009·28 cites·25 claims
- 1796US6004366AReverse flow air filter arrangement and methodDONALDSON CO INC·Filed 1998·Granted Dec 21, 1999·95 cites·17 claims
- 1895US9782713B2Air filter having fluted filter mediaDONALDSON CO INC·Filed 2015·Granted Oct 10, 2017·6 cites·26 claims
- 1995US6521009B2Reverse flow air filter arrangement and methodDONALDSON CO INC·Filed 2001·Granted Feb 18, 2003·65 cites·38 claims
- 2095US5690712AReverse flow air filter arrangement and methodDONALDSON CO INC·Filed 1996·Granted Nov 25, 1997·114 cites·20 claims
- 2194US6258145B1Reverse flow air filter arrangementDONALDSON CO INC·Filed 1999·Granted Jul 10, 2001·74 cites·17 claims
- 2294US5938804AReverse flow air filter arrangement and methodDONALDSON CO INC·Filed 1997·Granted Aug 17, 1999·117 cites·14 claims
- 2390US10556202B2Air filter having fluted filter mediaDONALDSON CO INC·Filed 2017·Granted Feb 11, 2020·2 cites·33 claims
- 2489US11123673B2Filter arrangements; housings; assemblies; and, methodsDONALDSON CO INC·Filed 2019·Granted Sep 21, 2021·2 cites·44 claims
- 2589US5123795AQuarter turn fastenerDONALDSON CO INC·Filed 1990·Granted Jun 23, 1992·74 cites·16 claims
- 2688US5129685AConnector system for air transfer ductsDONALDSON CO INC·Filed 1990·Granted Jul 14, 1992·53 cites·4 claims
- 2787US10252206B2Filter arrangements; housings; assemblies; and, methodsDONALDSON CO INC·Filed 2016·Granted Apr 9, 2019·2 cites·42 claims
- 2886US10343101B2Filter arrangements; housings; assemblies; and, methodsDONALDSON CO INC·Filed 2016·Granted Jul 9, 2019·2 cites·19 claims
- 2986US7455707B2Reverse flow air filter arrangement and methodDONALDSON CO INC·Filed 2003·Granted Nov 25, 2008·27 cites·67 claims
- 3085US11185810B2Air filter having fluted filter mediaDONALDSON CO INC·Filed 2020·Granted Nov 30, 2021·1 cites·28 claims
- 3171US4974881AAir transfer systemDONALDSON CO INC·Filed 1989·Granted Dec 4, 1990·19 cites·12 claims
- 3261US4856826AAir transfer systemDONALDSON CO INC·Filed 1988·Granted Aug 15, 1989·15 cites·20 claims
- 3357US11679352B2Filter arrangements; housings; assemblies; and, methodsDONALDSON CO INC·Filed 2021·Granted Jun 20, 2023·0 cites·51 claims
- 3452US4699639AAir-intake, moisture-eliminator duct apparatusDONALDSON CO INC·Filed 1986·Granted Oct 13, 1987·15 cites·2 claims
- 3548US2008041026A1Air cleaner assembly; components; and, methodsENGEL DONALD F·Filed 2007·Application pending·0 cites
- 3647US2008066435A1Air cleaner assembly; components; and, methodsENGEL DONALD F·Filed 2007·Application pending·0 cites
- 3744US5137308AAir transfer systemDONALDSON CO INC·Filed 1990·Granted Aug 11, 1992·13 cites·10 claims
- 3841USD425977SInside surface of a filter element having insert constructionDONALDSON CO INC·Filed 1998·Granted May 30, 2000·4 cites·1 claims
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Identity basis: PatentsView inventor disambiguation (2025Q4-odp release). How scoring works →