Inventor
Roy D. Lister
Inventor
Keller, TX, US
Overview
Patents· 7 as inventor
Public. Assignee & technology derived from the patent record. Each patent links to its LexDana page.
B04Cprimary
B04CApparatus using free vortex flow, e.g. cyclones36%
B01DSeparation21%
C02FTreatment of water, waste water, sewage, or sludge7%
C05FOrganic fertilisers not covered by subclasses c05b, c05c, e.g. fertilisers from waste or refuse7%
E21BEarth or rock drilling7%
F16CShafts7%
Y02ATechnologies for adaptation to climate change7%
Y02PClimate change mitigation technologies in the production or processing of goods7%
PatentTitleYear
8,955,691'Spiral ramp hydrocyclone'20155,185,087'Method of concentrating and deodorizing ruminant waste'19934,857,197'Liquid separator with tangential drive fluid introduction'19894,818,400'Cyclone and filter belt apparatus for dewatering'19894,786,412'Hydrocyclone having dewatering tube'19884,765,887'System for joining sections of a hydrocyclone separator'19884,324,438'Drilling deck bushing'1982Career & activity timeline
Assembled from patent assignee/location history and declaration credentials.
1982–1989Patents assigned to EAGLE PICHER IND INC (4)· patent assignee history
1982Based in Fort Worth, TX, US· patent location history
1988–1993Based in Keller, TX, US· patent location history
1989Patents assigned to AMOCO CORP (1)· patent assignee history
1993–2015Patents assigned to LISTER ROY D (2)· patent assignee history
1993Patents assigned to CORTEZ SABINO (1)· patent assignee history
2015Based in Winston-Salem, NC, US· patent location history
Inventor activity
Assignee and location history derived from the patent record.
Assignees
| Assignee | Patents | Span |
|---|---|---|
| EAGLE PICHER IND INC | 4 | 1982–1989 |
| LISTER ROY Dself | 2 | 1993–2015 |
| AMOCO CORP | 1 | 1989 |
| CORTEZ SABINO | 1 | 1993 |
Locations
| Location | Patents | Span |
|---|---|---|
| Keller, Texas, US | 5 | 1988–1993 |
| Winston-Salem, NC, US | 1 | 2015 |
| Fort Worth, Texas, US | 1 | 1982 |