The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 12, 1996
Filed:
Apr. 15, 1993
Douglas L Young, Nashua, NH (US);
Antoine G Abdulmassih, Hudson, NH (US);
Ingersoll-Rand Company, Woodcliff Lake, NJ (US);
Abstract
A hydrodynamic device for generating negative pressure excursions in a pulp slurry during fine screening, includes a plurality of half-foil members disposed on a substantially cylindrical outer surface of a rotor. The rotor is mounted within and co-axial with a substantially cylindrical screen having a circumferentially continuous apertured zone to define an annular screening chamber between the rotor and the screen. The half-foil members are collectively at least axially co-extensive with the apertured zone and have a leading edge which, also collectively, is inclined at a spiral angle relative to the axis of the rotor such that during rotation, the collective leading edge of the half-foil members conduct large particles downwardly through the screening chamber. A selection of hydrodynamic foil configurations is provided in order to adapt to a wide range of pulp types and screening conditions.