| 摘要 |
A method and apparatus for controlling the relative position of printing appearing on packages formed by form-fill-seal packaging machine in which individual packages are formed in substantially continuous fashion from a web of pre-printed package stock. Pre-printed registration indicia are detected on the web of package stock, and a control signal is generated which actuates a tension regulating device which varies the tension applied to the package stock as the package stock is formed into packages. In a preferred embodiment, the tension regulating device comprises a roll having selectable rotational resistance, over which the web is partially wrapped. |
