| 摘要 |
<p>Strapping head, comprising three wheels for driving the strap, i.e. an insertion wheel, a recovery wheel and a tensioning wheel, as well as a pressure roller associated with each of said drive wheels, and means for activating and deactivating the driving of said wheels. According to the invention, said tensioning wheel (6) is made to rotate by a movement cam (7), through an angle of rotation 'a' corresponding to an arc with a length equal to the maximum tensioning travelling distance of the strap, and the strap is driven by said tensioning wheel (6) in co-operation with a pressure roller (6a) which is displaceable so as to bear with pressure against the strap and the tensioning roller (6), with a predetermined delay with respect to the start of the tensioning roller (6). A single actuating motor operates a single drive belt (C) for driving all the moving parts of the machine.</p> |
