Abstract: A method and apparatus for winding synthetic fibers is disclosed. According to the invention, a yarn is wound around a bobbin without winding a tail bunch, at a high successful bobbin-to-bobbin yarn transfer rate for a variety of yarn properties, i.e. different in thickness, lubricant used, etc., while inhibiting the loosening of the yarn tail into single fibers and stably and easily forming a proper yarn tail length. Tail bunch removing work is not required and the winding process is stabilized. A yarn is wound around an empty bobbin using a yarn winding apparatus composed of a traverse fulcrum guide, a traverse device, a contact pressure roller, two spindles, a moving device for moving the spindles, and a yarn transfer device for introducing the yarn into a yarn holding portion for holding the yarn.

Abstract: A melt spinning pack, including a pack case, a spinneret having many spinning holes positioned at the bottom of the case, a pack cap having a polymer introducing hole at the center positioned at the top of the case, and a flow arranging plate having many flow arranging holes with restricted portions reduced in cross sectional area compared to the inlets of the holes positioned between the spinneret and the pack cap, satisfying the requirement that the contraction percentage R be 50% or less, respectively contained in the case.

Abstract: An apparatus for fluid treatment of yarn, which has a yarn passage and a fluid passage with a fluid outlet in the yarn passage, wherein the fluid passage has a substantially straight passage and an expanding passage existing between the end of the substantially straight passage and the fluid outlet, and that the width of the expanding passage in the direction parallel to the axial line of the yarn passage increases gradually from the end of the substantially straight passage to the fluid outlet.

Abstract: An apparatus for treating yarn with fluid designed to provide a yarn, which consists of a multifilament, with coherence by using a working fluid. The apparatus is provided with first and second components which have flat surfaces fixed in parallel against each other with a gap G (mm) provided between them, the first component having at least two fluid conduits which are provided with a specified crossing angle (.theta.) so that they cross each other on the extended lines of their axes and which are opened in the flat surface. The first and second components are fixed to satisfy the requirement in which the gap G between the flat surfaces facing each other is 0.2 mm or more but 5 mm or less, and they eject the working fluid under a specified pressure through at least the two fluid conduits onto the yarn, which runs between the flat surfaces, to provide the yarn with coherence.

Abstract: A method of measuring a profile of an object wherein an ultrasonic wave is radiated from an ultrasonic transducer toward an object supported by a supporting member in the water filled in a water tank, and a wave reflected at the surface of the object is detected by the transducer, and an apparatus for carrying out the method. A traversing device moves the transducer sequentially to a plurality of measurement points on an arc equidistant from a predetermined rotational center while opposing the transducer to the predetermined rotational center. A supporting device moves the supporting member relative to the transducer and sets the object in the predetermined position under water.