| 摘要 |
Measurement data required to control the unrolling web speed of paper tissue in a heavy primary or "machine" roll (10) are derived from the surface of the tissue machine roll (10) by means of a separate tachometer generator (12) driven by a speed measuring means in the form of a small- dimension endless belt (13) (or equivalent roller) mounted to contact the surface of the unrolling tissue. This area is compared (at 19) with a desired reference speed and any difference is fed back to control means (17) which controls a drive means (14) acting directly on the shaft of the machine roll. Thus in comparison with known power transmission by surface-belt drives for the machine rolls, quicker acceleration or deceleration and a shorter overall multi-roll line installation, are achieved, leading to less damage and breakage, retained creping and reduced tendency to ply separation. <IMAGE> |
