DEVICE FOR VIBRATING AND MOVING DOCTOR WHICH CAN BE RECIPROCATED IN LONGITUDINAL DIRECTION

An arrangement for longitudinally oscillating a doctor blade relative to the form cylinder in a printing press. The arrangement includes a double armed rocker having one arm coupled to the doctor blade and the other arm coupled to a hydraulic cylinder. The rocker is mounted on a central eccentric portion of a pivot shaft through a one way idler bearing and the pivot shaft is rotatably supported in a counteracting one way idler bearing. By oscillating the rocker, through sequential operation of the double acting cylinder, the pivot axis of the rocker is continuously displaced, causing the points of reversal of doctor blade movement to be continuously varied independently of the press operation, while maintaining a uniform stroke. In the illustrated embodiment, a pneumatic control is provided for controlling operation of the hydraulic cylinder, and thus the rocker arm and doctor blade movement.