| 摘要 |
<p>1,256,376. Apparatus for drawing thermoplastic products. ALGEMENE KUNSTZIJDE UNIE N.V. 8 Oct., 1969 [8 Oct., 1968], No. 49543/69. Heading B5B. A process for the drawing of a thermoplastic thread-shaped or ribbon-shaped product in a drawing zone between the point of arrival of the product on a feed roll and a draw roll which is driven at a circumferential speed that is higher than that of the feed roll, which process comprises the steps of feeding the product to the drawing zone, subjecting it to a first draw between the feed roll and at least one friction member in slipping contact with the product, localizing the drawing point as hereinbefore defined in the zone between the feed roll and the friction member, subjecting the thread to a second draw between the friction member and the draw roll, and discharging the drawn product from the drawing zone. In particular the process comprises feeding the thread to a driven feed roll 2, subjecting the thread to a first draw, feeding the thread to at least one friction member 4 over which the fibre slips, subjecting the thread to a second draw by feeding the thread to a draw roll 6 which is driven at a circumferential speed higher than that of the feed roll. The process may be used for linear polyester especially polyethylene terephthalate and linear polyamides especially nylon 6. The first draw may begin on the feed roll. The drawing point which is the point of maximum decrease in denier or drawing may be localized by continuously adjusting the temperature of a heatable zone, such as a feed roll, immediately prior to the drawing point. The friction member may be rotary or stationary through which liquid may be passed for controlling its temperature. The process may be used for spin drawing especially of polyethylene terephthalate when the driven friction member is heated to a higher temperature than the heated feed roll, the temperatures preferably being in the ranges 180‹ to 225‹ C. and 65‹ to 90‹ C. respectively. The frictional member and the feed roll may have matt chromium plated surfaces. In Fig. 3 for spin drawing nylon 6 the fibres are subjected to a relaxation process after the stretching by passing the fibres over rolls 12 and 13 which have a slower peripheral speed than the draw roll 6.</p> |
