| 摘要 |
<p>A driving roller transmits its motion by contact, to the successive layers of a material in sheet form, wound on to a tubular support. The roller forms part of a device for ensuring the winding on of the sheet material at a constant tension, irrespective of the speed at which it is delivered. The rotation of the roller is effected by the intermediary of a non-return system. This acts on the shaft of the roller, according to the amt. of material delivered, and is formed basically by two elements mounted on the driving shaft. Each non-return element is commanded by a jack, the piston of which acts on the end of a lever fixed solidly to the driving shaft, and causes its angular displacement. After having acted the jack is maintained at a constant predetermined pressure corresponding to the tension to be applied to the sheet material. System is esp. for the take-up mechanism of a loom. The need for expensive mandrels which are difficult to lift out when full and to replace with an empty, is avoided, and fragile electronic controls are also dispersed with. The device is simple to install and adjust.</p> |
