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:
Jul. 14, 1992
Filed:
Apr. 09, 1991
Michael I Sherman, Glens Falls, NY (US);
Glentech Inc., Glens Falls, NY (US);
Abstract
The efficiency of a diffuser, for washing or bleaching paper pulp, is enhanced by taking steps to ensure that the approximate upstroke speed is only slightly faster than the pulp upflow velocity, to provide an early warning indication of the tendency of the diffuser screens to plug, and to prevent upward movement of the screen, after completion of a downstroke, uncontrolled by the hydraulic system designed to effect movement. The pressure under the annular screen is sensed and compared to normal static pressure at the elevation of the screen by a D/P cell in a leg, and a computer controls the hydraulic system so that the screen upstroke speed is only slightly faster than the pulp upward speed. Early detection of a tendency to plug is provided by a pressure sensor within the hollow interior of the screen spaced from the screen orifices. To prevent gas from pushing the screen upwardly, during an initial part of an upstroke, the hydraulic system is operated to effect quick upward movement a small predetermined distance before continuous, smooth movement is effected.