Abstract: An X-Y plotter disclosed is of the type which moves a recording paper with no perforation by drive rollers and pinch rollers. A plurality of sharp projections are arranged on the outer surface of each of the drive rollers such as to enable an exact feeding of the paper without any slippage. These projections are formed by cutting in the outer surface of each drive roller with V-grooves parallel and orthogonal to the shaft of the drive rollers.

Abstract: A pen changing apparatus for a plotter is disclosed. A plurality of pens are mounted on a carriage in alignment with the axial direction of a shaft which is provided on the carriage as the sliding axis thereof. A guide shaft is fixed onto the carriage in the same direction as the shaft. A sliding lever for pressing any of the plurality of pens is provided on the guide shaft such as to be movable in the axial direction of the guide shaft and rotatable around the guide shaft. A solenoid rotates the sliding lever so as to press down a desired pen at the position where the sliding lever is located in resistance to a pen lifting spring or restore the pen to its original position by the urging force of the pen lifting spring.