Patent ID: 6106623
Filing Date: 2000-08-22
Classification: B41J

Abstract:
A coating apparatus for a printed sheet in which a coating material in a liquid state is applied on a medium already printed, which comprises:an on-demand coating head, which has a plurality of jet openings arranged in a direction parallel to left and right side edges of the printed medium, for producing a coating area having a width in the direction parallel to the left and right side edges of the printed medium by jetting out liquid droplets of the coating material through the jet openings in a direction substantially perpendicular to a face of the jet openings responsive to vibration of a piezoelectric element;primary coating scanning means for reciprocating the on-demand head on the printed medium in a primary coating scanning direction which crosses the left and right side edges of the printed medium;secondary coating scanning means for moving the on-demand coating head and the printed medium with respect to each other in a direction perpendicular to the primary coating scanning direction;signal producing means for producing at least one of a first edge position signal indicating an effective image edge position of the printed medium with respect to the primary coating scanning direction and a second edge position signal indicating a printed medium edge position; andcoating control means for controlling at least one of a liquid droplet jet from the on-demand coating head and a reciprocating movement of the on-demand coating head based on at least one of the first and second edge position signals.