ABSTRACT
Combing is a cyclic operation. The process on the feed side appears to be intermittent, however, on the delivery side, things are worked out in such a way that the material appears to be delivered continuously. This is because; it is necessary to grip a small portion of the lap at a time and then present the fringe to combing by cylinder needles. Further, the combed portion is also required to be pushed ahead before the next portion is brought in for subsequent combing operation. The complete operation, therefore, becomes cyclic where different motions occur sometimes one after the other whereas some other motions occur simultaneously. This necessitates a definite order of events and the occurrence of these events becomes a cycle – a ‘combing cycle’.
The whole cycle is divided into index numbers for which, there is a provision of an index wheel with numbers engraved on it. If any particular event is required to be set at a certain time, the corresponding index number is brought against the pointer, after which the setting is carried out. The setting for each event is described in detail with neat figures to understand the procedure e.g., the most important setting is the ‘step gauge’. The figure describes the shape and size of this gauge and also explains how this gauge enters the machinery parts, which are set accordingly.
An important piece of information is the piecing wave formation due to intermittent operations on the feed side. It has been now, universally accepted that reducing the number of drafting rollers in the draw box has a beneficial effect in controlling this defect. Yet another thing which accepted is the method of web collection, as delivered by the detaching rollers after combing. Thus, in every modern comber, the web collection is asymmetric and this helped the reduction of the piecing wave effect quite substantially. The chapter ends with a simple process – sliver collection into a suitable can.
