Patent ID: 6766735
Filing Date: 2004-07-27
Classification: B41F

Abstract:
Printing apparatus for objects to be printed, having a circular indexing table which rotates about a vertical axis and has a rotary drive, having at least one pallet carrier arranged on the circular indexing table and in each case having a pallet that can be arranged on the pallet carrier, at least one printing unit arranged above the pallets circulating around the vertical axis, the printing unit and the pallet being arranged such that they can move relative to each other in the vertical direction, and the pallet carrier arranged on the circular indexing table assuming a plurality of electrically indexable, stepwise predefinable rotary positions with respect to the printing unit, characterizedin that the rotary drive has an electric motor, the electric motor being an asynchronous motor (4) or a servo motor, which is connected to a frequency converter or to a servo converter, in that at least one of the frequency and the voltage of the frequency converter or of the servo converter can be controlled, in that a rotary encoder is arranged directly on the electric motor, in that a control apparatus is connected to the frequency converter or the servo converter, the control apparatus being capable of being programmed in such a way that individual rotary positions can be skipped, in that, by means of the control apparatus, the electric motor can be controlled clockwise and anticlockwise, and in that, at least in one rotary position, a mechanical fine positioning apparatus (12) is arranged on the circular indexing table (3) and on the printing-unit carrier (10) moves vertically relative thereto, in order to achieve register accuracy.