Rieter

Waste removal

Index

The eliminated material (short fibers, foreign matter, neps, etc.) remains trapped in the  circular combs. Removal is performed by a rapidly rotating brush mounted below the comb-carrying cylinder (Fig. 59). This removal occurs when the half-lap comb engages with the brush, which then ejects the noil into a duct forming part of a suction system. This leads to a filter drum behind the machine (older system), to a fiber separator (Fig. 60) within the machine, or to a central waste removal system (Fig. 61).
Although this normal brushing-out is a very efficient way of cleaning the circular combs, some material can still remain caught in them, disturbing the combing operation and causing deterioration in quality. To deal with this problem, modern combers feature a so-called slow cycle. At precisely adjustable, pre-set intervals, the movements of the machine parts are slowed down to 1/5 of normal speed. Only the brushes continue to rotate at full speed, thus subjecting the circular combs to intensive treatment to produce a thorough cleaning effect. Fig. 62 shows the increase in the level of noil with uninterrupted full-speed running time. Fig. 63 demonstrates the stability of the noil level when a periodic cleaning cycle is inserted into the operating sequence. The  top comb is self-cleaning owing to the action of the thick sheet passing through its teeth when pulling the top comb out of the sheet.

Fig. 59 – Stripping the circular combs

Fig. 60 – Removal of waste using a fiber separator

Fig. 61 – Central waste removal

Fig. 62 – Change in combing-out as the circular combs fill up. A, noil percentage; B, running time of the machine (t(min))

Fig. 63 – Keeping combing-out constant by periodic intensive cleaning of the circular combs