Yarn feeding unit for rapier looms and projectile looms

Abstract

The invention relates to a yarn feeding unit (F) with: a stationary storage body (3) for a yarn store (V); a housing arm (2), which extends beyond the draw-off end (4) of the storage body (3) and which supports a coaxial draw-off eyelet (9) in front of the storage body (3); a controllable yarn tension device (10) located downstream from the draw-off eyelet (9), and; a brush ring (B) with an elastic bristle bunches (16), which contact the storage body (4) and, when unstressed, define a smaller inside diameter (d2) than the outside diameter (d1) of the storage body (3) in a cylindrical surface area adjacent to the draw-off end (4). The bristle bunches (16) contact the cylindrical surface area (7) with a predetermined contact force and form a balloon breaker (K) for the yarn section (S) drawn from the yarn store (V) via the draw-off end (4) and into the draw-off eyelet (9).

Description

technical field [0001] The invention relates to a yarn feeding device of the type stated in the preamble of patent claim 1 . Background technique [0002] On the yarn feeding device disclosed in European patent EP 0 622 485 A, the position of the brush pile ring is determined so that the bristle pile touches the unwinding end of the circular storage body from the front, so as to be arranged on the unwind ring. The downstream controllable yarn brake generates a pre-defined, minimum possible basic tension and guides the yarn being pulled to the withdrawal end. Due to the position of the brush ring on the withdrawal end, there is a relatively large axial distance between the yarn storage device on the storage body and the bristle tufts. Because the yarn unwinding on rapier and projectile looms is intermittent and the yarn speed varies greatly, occasional Great centrifugal forces are produced which cause the well-known undesirable balloon effect, ie the yarn is blown up from t...

AI Technical Summary

Problems solved by technology

In this way, although the balloon effect and the yarn tension changes caused by the balloon effect are weakened, the input yarn lacks the necessary basic tension, and the yarn geometry is irregular; due to the balloon control ring and storage body There is a gap between the surfaces, the yarn does not change direction continuously through the unwinding end, it only occasionally touches the unwinding end, causing a periodic or irregular increase in the yarn tension upstream of the controllable yarn brake

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