DETECTOR FOR FAILURE OF PAPER FEED IN COPYING MACHINE

摘要

PURPOSE:To detect not only a jam of a recording paper but also a deviation of an image position on the recording paper by monitoring the period of presence of the recording paper and the period of absence of the recording paper in two positions of a paper feeding part and a paper ejecting part on a basis of a rotary encoder connected to the shaft of a recording drum. CONSTITUTION:An angle period setting means 29 sets an angle period for check on a basis of pulses from rotary encoder 12. The first paper position deciding means 30 decides that the recording paper exists on a paper feed sensor 4 in the first angle period, and the second paper position deciding means 31 decides that the recording paper does not exist on the paper feed sensor 4 in the second angle period. The third paper position deciding means 32 decides that the recording paper exist on a paper eject sensor 9 in the third angle period, and the fourth paper position deciding means 33 decides that the recording paper does not exist on the paper eject sensor 9 in the fourth angle period. A paper feed failure deciding means 34 decides a failure of paper feed on a basis of outputs of the first - the fourth position deciding means 30-33 and sends the output to a processing means 35.