Abstract: The thread end to be used for rejoining in an open-end spinning frame is prepared by cutting it to size and then introducing it into a pipe with a vigorous air flow running through the pipe and contacting the thread end with a vibrating blade, freeing the end of short fibers, tapering the thread end and untwisting the fibers that comprise the thread end.

Abstract: An apparatus for delivering a skein end of a thread wound on a reel to an apparatus for returning the skein end to a spinning machine. The apparatus for delivering the skein end comprises a device for unwinding a reel on which the thread is wound, a capturing device for capturing the skein end of the thread, a transferring device to transfer the thread from the capturing device to a device that returns the thread to the spinning machine, and a detecting device for detecting the presence of the thread in the transferring device. Another aspect of the invention generally features an apparatus for rejoining the skein end of a thread wound on a reel, the thread having been disconnected from the reel due to one of a plurality of different events. The apparatus comprises an unwinding device for unwinding the reel; a capturing device for capturing the skein end of the thread wound on the reel, a cutting device for cutting a portion of the thread captured by the capturing device.

Abstract: A method for rejoining yarn in an open-end spinning machine in which the rejoining is effected by feeding intact fibres to the rotor but preceding the rejoining by an operation in which the sliver is cleared and the carder is cleaned by the high-vacuum suction nozzle brought into correspondence with the air intake port.

Abstract: A method for rejoining yarn in an open-end spinning machine in which the rejoining is effected by feeding intact fibres to the rotor but preceding the rejoining by an operation in which the sliver is cleared and the carder is cleaned by the pneumatic action of a blowing nozzle brought into correspondence with the air intake port.

Abstract: This invention relates to a device for regulating the winding speed in the formation of cross-wound conical bobbins where the yarn is withdrawn at constant speed from a rotor spinning unit by a lever system able to displace the friction drive band of the drive roller for the conical bobbin under formation, in order to vary the average resultant value of the varying winding speed during each double stroke of the yarn guide element. Said lever system is operated by a two-direction rotary drive source which is activated when a linear position element, associated rigidly with the yarn storage element, senses by known means that abnormal storage swings persist.

Abstract: A yarn storage and return device for yarn being wound on a conical bobbin driven at a constant speed. The device comprises a lever system for storing and returning the yarn and for regulating and monitoring the amount of stored yarn. The yarn is drawn into the storage position by an arm of the lever system and is then released (i.e. returned) from this storage position. This returning operation releases the yarn from its storage position and replaces it (returns it), to its normal feed path. The device also comprises a yarn tension measurer, an electric comparator, and an electric control unit to measure and compare the yarn tension, and to process an electric controlling signal to activate a drive motor. The drive motor actuates a tensioning element which affects the storage operation of the device.

Abstract: A device and method for winding conical bobbins with yarn withdrawn at constant speed from individual spinning units, and comprising: a deflecting roller, which moves backwards and forwards by a swinging arm, which compensates for the different speeds at which the yarn is collected on the bobbin under formation wherein yarn is drawn into the storage position and is then released from this storage position, (i.e. returned). This returning operation releases the yarn from its storage position and replaces it (returns it), to its normal feed path; two proximity sensors which defines the range of swing of the yarn storage and return arm; an electronic control unit which receives an electrical signal from the proximity sensors when the arm swings stray outside the regular range to generate, an electrical control signal which activates a pressure variator which varies the pressure on a disc yarn tensioner. This changes the tension on the yarn to return the storage swing to within the regular range.

Abstract: A device and method for winding conical bobbins with yarn withdrawn at constant speed from individual spinning units, and comprising: a deflecting roller or similar element, which is connected to and moved backwards and forwards by a swinging flat element for yarn storage and accumulation, to compensate the variation in the speed at which the yarn is collected on the conical surface of the bobbin under formation wherein yarn is drawn into the storage position and is then released from this storage position, (i.e. returned).

Abstract: A device and method for winding conical bobbins with yarn withdawn at constant speed from individual spinning units, and comprising: a deflecting roller, or similar element, which is connected to and moved backwards and forwards by a swinging arm which by storing and returning the yarn compensates for the different speeds at which the yarn is collected on the conical surface of the bobbin under formation wherein yarn is drawn into the storage position and is then released from this storage position, (i.e. returned).

Abstract: Rotary twister element suitable to keep under tension the fibres during the twisting operation in a frictional open-end spinning process, constituted by a solid, hollow, reduced-thickness element with perforated skirt, which is internally provided with a suction duct defining a longitudinal slot, the edge of which constitutes the thread formation line, is suitably inclined relatively to the general trix of the same solid, hollow element, as a function of the direction of rotation of the solid element, and of the direction of thread extraction. Also a screen is provided for the air dragged by the rotation of the solid element, which may have a cylindrical shape, a cone frustum shape, or the shape of any other revolution solid.

Abstract: A friction open-end spinning process wherein the fibers of the feeding fiber sliver, once separated into discrete fibers, are sucked by a suction slot on a revolving twister element provided with a perforated surface, to feed the free end of the yarn being formed. The process is characterized in that the fibers are fed in a direction parallel to the free end of the yarn being formed, are kept under an adjustable tension throughout the twisting operation, and are subjected to a progressively increasing twist from the open end of the yarn being formed onwards. The device embodying the above process uses a revolving flat disc provided with perforations arranged according to an annulus as the twister element. This element cooperates with a sucking slot, the edge of which, consituting the yarn formation line, is positioned according to a chord of the disc.

Abstract: An improved device to piece-up yarn and doff yarn packages on open-end spinning machines. The device comprises a carriage (12) equipped with specific means for the tasks of piecing-up yarn and doffing yarn packages, said carriage being supported cantilever-wise by an arm (13) secured to a trolley (15) able to run on lengthwise guides (17), said carriage (12) being equipped with an arm (20) to hold tubes which cooperates with a store (18) of tubes.