Patent assignee · US · COMPANY

ESSEF Corporation

41Patents
0Active
41Granted
37Portfolio score

Filing activity: Aug 8, 1985 → Feb 20, 2003

Most-cited patents

PatentTitleAreaCited byStatus
US6793095B1 Blow-molded pressure tank with spin-welded connector Emerging Cross-Sectional Technologies 45 Expired
US5900107A Fitting installation process and apparatus for a molded plastic vessel Emerging Cross-Sectional Technologies 44 Expired
US5096083A Polyethylene shipping drum Performing Operations; Transporting 42 Expired
US4753726A Distributor for filters Performing Operations; Transporting 41 Expired
US5121852A Dynamic pressure relief seal for pressure vessels Performing Operations; Transporting 37 Expired
US6485668B1 Method for fabricating composite pressure vessels and products fabricated by the method Performing Operations; Transporting 34 Expired
US5819978A Two piece composite inlet Emerging Cross-Sectional Technologies 29 Expired
US5759414A Swimming pool main drain assembly Fixed Constructions 29 Expired
US5368073A Hydropneumatic pressure vessel having an improved diaphragm assembly Mechanical Engineering; Lighting; Heating 27 Expired
US6190598A Method for making thermoplastic composite pressure vessels Emerging Cross-Sectional Technologies 26 Expired
US5568878A Filament wound pressure vessel having a reinforced access opening Mechanical Engineering; Lighting; Heating 25 Expired
US5356589A Method and apparatus for forming rotationally cast tank liner having an end fitting Performing Operations; Transporting 24 Expired
US4705468A Apparatus for rotationally casting a plastic tank liner having an access fitting Performing Operations; Transporting 22 Expired
US6171423A Method for fabricating composite pressure vessels Mechanical Engineering; Lighting; Heating 21 Expired
US5268096A Pool drain assembly Fixed Constructions 21 Expired
US4637435A Antiseal arrangement for hydropneumatic pressure tanks Mechanical Engineering; Lighting; Heating 20 Expired
US5045187A Regeneration system for water conditioners such as water softeners Emerging Cross-Sectional Technologies 20 Expired
US4944887A Regenerative diatomaceous earth filter Performing Operations; Transporting 19 Expired
US5072851A Dynamic pressure relief seal for pressure vessels Performing Operations; Transporting 16 Expired
US5526994A Filament-wound isotensoid pressure vessels having geodesic domes Mechanical Engineering; Lighting; Heating 16 Expired
US5556497A Fitting installation process Emerging Cross-Sectional Technologies 15 Expired
US4994132A Method and apparatus for attaching an insert in a hollow body Performing Operations; Transporting 15 Expired
US5878773A Auxiliary flow path valve Emerging Cross-Sectional Technologies 14 Expired
US5388720A Flanged diffuser and air cell retainer for pressure vessel Mechanical Engineering; Lighting; Heating 13 Expired
US5484079A Hydropneumatic filament-wound pressure vessel Mechanical Engineering; Lighting; Heating 12 Expired

Source: USPTO / EPO open patent data. Counts and citation impact are objective bibliographic measures.