| 摘要 |
Method of monitoring a line of adhesive deposited on a travelling paper web to check for accidental omission of adhesive wherein the adhesive has a distinguishing relative permittivity and is sensed by a capacitive proximity sensor. The web may be plugwrap material for cigarette filter rod, the adhesive being provided to anchor filter tow in position when the plugwrap is wrapped around it. The method avoids various disadvantages associated with other automatic monitoring devices such as optical devices and infra-red devices. |
