Densitometric sensing device for use in printing presses

US4806002A · kind A · utility

Assignee

• MAN Roland Druckmaschinen AG · DE

Inventors

• Claus Simeth · Mühlheim, DE
• Peter Schramm · Erlangen, DE

Key dates

• Filing date: Sep 14, 1987
• Grant date: Feb 21, 1989
• Expiry date: Sep 14, 2007

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B41F33/0036
• WIPO field: Textile and paper machines
• WIPO sector: Mechanical engineering

Abstract

A densitometric sensing device in which a density measuring head, which is part of the device, traverses an ink test strip printed on a page which is fed to or placed on the device. The problem of misalignment between the thus-placed ink test strip and the scanning direction of the density measuring head is avoided by providing a plurality of density measuring receivers in the measuring head, mounted transverse to the direction of travel so that the ink test strip is always under some of the receivers. The measured density values of all of the receivers are passed to a comparison circuit which cooperates with a logic circuit to determine from the values of the signals themselves which should be used to produce a composite density value, which is then used as the density for the zone being scanned.