| 摘要 |
<p>An extension and centering device for rope fabric is consisting of: an extension device, including a carrying structure at least two extension rollers with double helical rifling, driven in rotation in opposite sense of the advancing of the fabric and having their axes parallel, and sensor means, sensible of lateral change of direction of the fabric, fitted after the above mentioned rollers; each roller is divided in two tracts of substancial the same length which are engaged between them idle; the adjoining tract between them of the two rollers are put into rotation by respective motors; there are also forseen piloted drives of the above mentioned sensors to change the speed of the motors on the other side of the lateral movement of the fabric, causing the variation of rotation speed of the two tracts of rollers connected to them; the increase of rotation speed of the two tracts causes the mouvement towards the outside of the fabric in the opposite side of the one in which it was moving until the pre-established direction is achived again and the motors together with the respective tract of rollers return to turn at the same speed.</p> |
