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:
Nov. 25, 1986
Filed:
Sep. 03, 1985
Bertold Grutzmacher, Dossenheim, DE;
Karl-Heinz Krestyn, Leimen, DE;
Heidelberger Druckmaschinen AG, Heidelberg, DE;
Abstract
A sheet feeder of a printing machine has sheet separating and conveying facilities and a stack table which raises a stack of sheets by means of a controlled lift drive so that a respective uppermost sheet of the stack is in an operating position for the sheet separating and conveying facilities, the sheet separating facility including separating suckers for raising, in timed sequence, a respective trailing sheet end, as viewed in sheet conveying direction through the feeder, a suction line connecting the separating suckers to a suction source, a pressure measuring device connected in the suction line for determining an actual instant of time at which a respective sheet is sucked up by the separating suckers, a comparator device for comparing the actual suction instant of time with a nominal suction instant of time generated in synchronism with rotation of the printing machine to determine a difference value, a comparator device for comparing the difference value with a value corresponding to an optimum height of the stack of sheets, and a lift drive for raising the stack of sheets to compensate for a given deviation of the difference value from the optimum height value.