| 摘要 |
The invention relates to an apparatus (100) for wrapping a load (104), comprising a film dispenser (116) for dispensing a film and including a film dispensing drive (124); a rotational drive system (108) for providing relative rotation between the load (104) and the film dispenser (116) during a wrapping cycle; an idle roller (134) configured to sense movement of the film dispensed by the film dispenser (116); and a controller (160) configured to operatively couple the film dispensing drive (124) and the rotational drive system (108) such that, for at least a portion of a revolution of the film dispenser (116) relative to the load (104) during the wrapping cycle, the film dispenser (116) dispenses a selected length of the film corresponding to the portion of the revolution, wherein the controller (160) is further configured to identify a film break based on a speed or direction of rotation of the idle roller (134). The invention further relates to a method of sensing a film break in film to be wrapped around a load (104) being wrapped during a wrapping cycle, comprising providing relative rotation between a film dispenser (116) and the load (104) to dispense the film around the load (104); sensing movement of the dispensed film with an idle roller (134); comparing the sensed movement of the dispensed film to expected movement of the dispensed film; and identifying a film break based on a speed or direction of rotation of the idle roller (134). |
