| 摘要 |
PURPOSE:To make it possible to correct the conveyed quantity of a wrapping material in either direction, by using a pair of mark readers to detect the deviation in the conveyed quantity in terms of read marks printed on the wrapping material. CONSTITUTION:It is supposed that the pitches between read marks on a wrapping material 1 are Pi (i=1, 2...) and have a relationship Po-Pi=DELTAPi where Po denotes a reference pitch for the conveyed quantity of the wrapping material. If a relationship SIGMADELTAPi=DELTAQ (or -DELTAQ) has arisen after several reference pitches Po of conveyance of the wrapping material 1 and a bottom material on a conveyor, one 41A (or 41B) of a pair of mark readers 41A, 41B disposed upstream and downstream as to the direction of conveyance of the wrapping material detects no read mark but the other reader 41B (or 41A) detects a read mark when the wrapping material is stopped. A driver for the conveyor is operated by a controller on the basis of a signal produced as a result of the detection of the read mark, to move a plate up (or down) to decrease (or increase) the conveyed quantity of the wrapping material and the bottom material by Po-DELTAQ (or Po+DELTAQ) in the next reference pitch. |
