Patent ID: 8642114
Filing Date: 2014-02-04
Classification: B41F

Abstract:
1. A method for operating a system for coating printing materials with coating fluids, the method comprising the following steps: in a first step, coating printing material with a first coating fluid using a coating device of the system while keeping a first feed device of the system connected to the coating device for feeding the first coating fluid to the coating device with the first feed device and circulating the first coating fluid in a circuit including the first feed device and the coating device; in a second step following the first step, coating printing material with a second coating fluid using the coating device while keeping a second feed device of the system connected to the coating device for feeding the second coating fluid to the coating device with the second feed device; in a third step carried out after the first step and at least to some extent during the second step, flushing through the first feed device with a cleaning fluid while operating a first reversible pump and a second reversible pump of the first feed device in the same delivery direction in tandem operation; and between the first step and the third step, short-circuiting the first feed device and checking to determine if the short-circuiting of the first feed device has been carried out correctly by generating a vacuum in the first feed device while operating the first reversible pump and the second reversible pump in mutually opposite delivery directions, monitoring the vacuum with a sensor, and detecting any incorrectness of the short-circuiting on a basis of a drop in or lack of buildup of the vacuum.