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. 05, 1977
Filed:
Feb. 23, 1976
H William Derrick, Jr, Williamsville, NY (US);
Derrick Manufacturing Corporation, Buffalo, NY (US);
Abstract
A vibratory screening apparatus has a pair of screen cloths in close face to face abutment with the wires of the lower screen cloth generally intersecting the openings of the upper screen cloth to prevent 'blinding' of the upper screen cloth by reason of the tendency of the wires of the lower screen cloth to prevent engagement of particles in the upper screen cloth of a size which would tend to clog the openings of the upper screen cloth. The mesh size of the lower screen cloth may be equal to the mesh size of the upper screen cloth or slightly larger than the upper screen cloth openings up to about 50 per cent larger. The superposed screen cloths may rest upon a much coarser mesh screen which serves merely as a structural support for the screen cloths and does not perform a screening function.