Rieter

Sequence of operations in a rectilinear comber

Index

Fig. 3 – Sequence of operations

(a) Feed rollers (S) move lap sheet (W) forward by a small amount (4.3 - 6.7 mm), while nippers (Zo/Zu) are held open (feed).

(b) Upper nipper plate Zo is lowered onto cushion plate (Zu) so that the fibers are clamped between them (nipping).

(c) Combing segment (K), mounted on rotating cylinder (Z), sweeps saw-teeth through fiber fringe (B) and carries away anything not held by the nippers (rotary combing).

(d) The nippers open again and move toward detaching rollers (A) (nippers forward).

(e) Meanwhile detaching rollers (A) have returned part of the previously drawn-off stock (web V) by means of a (partial) reverse rotation, so that the web protrudes from the back of the detaching device (web return).

(f) In the course of the forward movement of the nippers the projecting fiber fringe (B) is placed on the returned web (V) (piecing).

(g) The detaching rollers begin to rotate in the forward direction again and draw the clamped fibers out of web (W) held fast by feed rollers (S) (inside the nippers) (detaching).

(h) Before the start of the detaching operation, top comb (F) has thrust its single row of teeth into the fiber fringe. As the fibers are pulled through the teeth of the top comb during detaching, the trailing part of the fringe is combed, thus making up for the inability of the circular combs to reach this part of the fringe (passive combing by the top comb).

(i) As the nipper assembly is retracted, the nippers open for the next feeding step. The top comb is withdrawn. A new combing cycle begins.

(k) Contrary to the movements of the other parts, the combing cylinder rotates continuously. During this rotation and at a certain instant the combing segment is brought into the vicinity of a rapidly revolving brush mounted below the combing cylinder. This brush removes the imperfections, etc., from the combing segment, and ejects them into an extractor that carries the noil away to a collecting filter system.

All these mechanically very demanding processing steps are carried out on 8 combing heads simultaneously at speeds of up to 500 times per minute (in Rieter‘s current  E 66 comber generation).