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:
Jan. 11, 1977
Filed:
Jul. 07, 1975
John M MacPhee, Rowayton, CT (US);
Charles Robert Gasparrini, Rye, NY (US);
Baldwin-Gegenheimer Corporation, Stamford, CT (US);
Abstract
A sheet material decurling apparatus for use with a machine having a sheet conveyor comprises a trough member which includes two elongate, sheet supporting members, each having an arcuate upper surface with a radius greater than 250t, where t is the thickness of the sheet material. An elongate fillet, curved in the direction opposite to and joining the sheet supporting member surfaces, has a radius less than 15t. Further, the angle formed between the planes tangent to the sheet supporting member surfaces at the lines of transition therefrom into the fillet is in the range of 60.degree. to 120.degree.. A series of vacuum conduits are disposed in the trough member adjacent the bottom of the fillet and have a total cross-sectional area of approximately 0.07 inches square per linear foot of trough member. A vacuum pump is connected to the vacuum conduits to effect air flow downwardly through the trough member. The conveyor draws the sheet material across the trough member with the curl directed downwardly so that air flow caused by the vacuum pump can pull the sheet material down onto the sheet supporting member surfaces and into the fillet surface to impart a bend, opposite to that of the curl, to the sheet. The trough member geometry causes effective sheet decurling without imparting additional curl to the sheet. The vacuum conduit sizing reduces the capacity of the vacuum pump needed for effective decurling while allowing operation on sheets having widths less than the decurler capacity without covering the exposed conduits.