| 摘要 |
Device to control the feeding of the strap in a strapping machine, comprising at least one fast driving wheel (4) and one slow driving wheel (2) which are mounted on fixed axes, the strap (R) being guided on the periphery of both driving wheels, and wherein pressure elements (5 and 14) are provided to press the strap (R) against the periphery of one and/or the other of the driving wheels, so as to ensure feeding thereof. The pressure elements are mounted on an oscillating sector (8) which is operated in response to tensioning of the strap. On the oscillating sector (8) there is also mounted a strap transmission wheel (13), located at a distance from the pressure elements, which imparts on the oscillating sector (8), according to the tension of the strap (R), an oscillation such as to transfer the contact pressure of the strap from the fast driving wheel (4)-for the fast recovery step-onto the slow driving wheel (2)-for the slow tightening step-merely through the alternative action of the pressure elements.
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