Abstract: A method and apparatus for controlling an optical printer where respective light emitting elements are energized for light emission based on one line amount of received image data for a time equal to an ON time of a strobe signal thereby to form an image on a photosensitive member. The strobe signal is selected from a group consisting of a predetermined number of base signals each having a different ON time and one or a plurality of composite signals each composed of a different combination of the base signals. The one line amount of image data are outputted for a number of times equal to the number of base signals, within a time allotted for one line amount of exposure. The light emitting elements corresponding to the image data are energized for light emission for a time equal to the ON time of the selected strobe signal.

Abstract: A shredding machine which comprises a pair of juxtaposed cutting rollers for shredding paper material, a paper feed tray movable between lowered and elevated positions and adapted to support thereon the paper material to be shredded, a feed roller assembly for feeding the paper material from the paper feed tray towards the cutting rollers, a protective cover supported for movement between closed and opened positions and for covering a space above the paper feed tray when in the closed position; and a control for moving the paper feed tray from the elevated position towards the lowered position in response to the movement of the protective cover from the closed position towards the opened position.

Abstract: A shredding machine includes a pair of juxtaposed cutting rollers for shredding paper material, a movable paper feed tray for supporting the paper material to be shredded on it, a paper feed tray drive motor capable of moving the paper feed tray between lowered and elevated positions, a paper feed mechanism and a control circuit for controlling the shredding operation. The paper feed mechanism comprises paper feed rollers for feeding the paper material from the paper feed tray towards the cutting rollers, a paper feed roller drive motor for driving the paper feed rollers and an actuator for detecting the position of the uppermost paper of a stack of papers placed on the paper feed tray. The operation of the paper feed mechanism is interrupted in the case where the actuator is not activated by the stack of papers over a predetermined period of time. Abnormal conditions of the drive motors can be detected by the control circuit on the basis of an electric voltage being supplied to each motor.