| 摘要 |
PURPOSE:To cut roll paper to prescribed length, irrespective of variations of size of an original, by using a shift register as a cutting signal generating means, in an automatic paper feed device of a copying machine, etc. CONSTITUTION:When an original 5 is inserted, a switch 7, and subsequently, a switch 8 are turned on, and a switch flag STF of a microcomputer is set. Also, (d) is set to an address counter, and an initial bit Mo of the address (d) of an RAM is set to ''1''. As a result, a paper feed clutch is turned on, and roll paper is fed into a paper feed port 13, synchronizing with the original 5. A pulse signal P of a pulse generator 15 is applied to an interruption terminal of the microcomputer, following a rotation of a paper feed roller, contents of the RAM memory address (d) are shifted to the left, the back end of the original passes through the switch 7, and after that, a cutting device 14 is turned on when the ''1'' signal has been inputted to a prescribed bit of a prescribed address, therefore, variations of cut size do not occur. |
