Abstract: This invention relates to an apparatus for emergency fiber supply to a spinning unit in an open-end spinning machine. According to the invention, a sensing unit controls an electromagnetic coupling and fiber supply device, such that a break in the yarn is rapidly detected and the fiber supply is immediately disengaged, even if the conventional thread breakage detector fails.A sensing unit is disposed in that portion of the wall of a cover that extends into the spinning rotor interior. It is adapted to respond to the excess accumulation of unspun fibers and/or an undue increase in temperature by disconnecting the electromagnetic fiber supply coupling via the thread breakage detector circuit to which it is connected. The sensing unit can be a pressure sensitive microswitch, a bimetallic relay, a thermistor, or a combination of these elements.

Abstract: A single-step stable method of producing spun-twisted yarns. A twist point is located on the frictional surface of a take-off funnel of the spinning rotor. A strand material which forms a component of the final spun-twisted yarn product is exposed, between feed rollers and said twist point, to an appropriate combination of transport effects of a pneumatic field of force and a mechanical field of force. For this purpose, the tube, through which the strand material is supplied, is determined in dependence on the pneumatic conditions prevailing in the spinning rotor.

Abstract: A method of and apparatus for frictional open-end spinning which is an improvement upon that disclosed by the co-assigned U.S. Pat. No. 4,168,601. Continuously supplied separated fibers are deposited onto a first, frictional carrying surface provided on a revolving carrier and designed for conveying the fibers to the mouth of a wedge-like gap defined by said frictional carrying surface and a second frictional surface provided on a second revolving carrier moving in said wedge-like gap in the opposite direction relative to the first, frictional carrying surface. The fibers are twisted to yarn in the mouth of the wedge-like gap due to the contact with said frictional surfaces of which one is convex and the other concave. The yarn is withdrawn from said gap in a lateral direction and the twist propagation is prevented.

Abstract: There is disclosed an apparatus for the frictional spinning of yarn on the open-end principle. The apparatus includes a mechanism for supplying separated fibers onto one of frictional surfaces provided on respective rotary carriers inserted one in the other and forming a wedge-like gap therebetween in the mouth of which fibers are twisted due to friction with the two frictional surfaces moving in opposite directions in said wedge-like gap, and a mechanism for withdrawing the yarn from said mouth of said wedge-like gap and adapted to prevent any twist propagation, one frictional surface being concave and the other being convex relative to the yarn building region in the mouth of the wedge-like gap. In accordance with the invention a carrier through its front opening situated opposite its second front opening for delivering yarn withdraw from the mouth of the wedge-like gap.