Abstract: Method and apparatus suitable for producing a spun yarn at high speed from short fibers less than 50 mm. in length. A bundle of fibers having a particular thickness distribution in its width direction is supplied through a fluid jet false-twist nozzle in which a throttle portion connecting the upstream and downstream portions of the yarn passageway is provided non-eccentrically or eccentrically with respect to the downstream portion, and the downstream portion has a fluid conduit opening eccentrically there into and inclined toward the outlet end of the downstream portion. Air preferably containing water at room temperature in the form of mist is used as the fluid jetted through said nozzle.

Abstract: A novel process for producing yarns at high speed by drafting a sliver or roving of short fibers. The process dispenses with rings, travellers or spindles, and a single gas false twist member is effectively used. The process comprises leading a bundle of short fibers to said false twist member and feeding to the twisting zone of the bundle of short fibers an extremely fine multifilament yarn preferably in contact over a rotary body, at a sufficiently low tension and at a speed faster by 50-90% than the spinning speed of the bundle of short fibers so as to restrain the fiber bundle within one-directional spirals and two-directional composite spirals. The resulting composite spun yarn has a good touch because the fiber bundle has become non-twisted. By changing production conditions, the yarn can be formed into any desired shape from even yarn to nep yarn.