PURPOSE: To simplify the structure of a control system in a web constant-speed feed part, by dispensing with a tension variation between a backward roll and a web drawing roller in a web sizing intermittent feeder, while controlling each of the web constant-speed feed part and a sizing intermittent feed part separately.

CONSTITUTION: A web 12 of a backward roll 10 is given back tension by a brake gear 16 and delivered through each of pass rolls 18 and 20. The web 12 is interposingly held between a constant-speed feed roller 24 and a nip roller 26 and fed to the inside of a loop chamber 32. The web 12 being fed out of a web constant-speed feed part 22 forms a loop 48 inside the loop chamber 32. When the loop 48 shades the light of a photoelectric detector 44, its output signal is transmitted to a control circuit 42 whereby a roller 36 is controlled for intermittent rotation by the control circuit 42. After the loop 48 of the web 12 is interposingly held between the roller 36 and a nip roller 38 and delivered to the next process, when the next loop 48 is formed inside the loop chamber again, a motor 40 is intermittently rotated. Repeating these movements afterward, the loop is fed out toward the cutting process length by length as specified.