For the setting, more especially thermosetting, of threads or yarn it is known to use a rigid heat-resistant bobbin sleeve, consisting more especially of metal, onto which the yarn is wound in close parallel layers.
The thread tensile forces arising during the thermosetting have to be absorbed by the sleeve body. The forces are directed radially towards the center of the sleeve. The shaping of a heat- and compression-resistant setting sleeve thus differs very severely from a conventional perforated dyeing sleeve. The winding diameter has to be very large, in order on the one hand to offer sufficient delivery weight for a following process, but on the other hand to make the thread layers wound parallel on the body non-elastic (non-resilient) relative to the next thread layers wound thereabove. Only thus can the shrinkage process succeed whilst maintaining the thread length.
In order to be able to dye the yarn material after the setting, the yarn is rewound in a rewinding process into cheese bobbins. The bobbin sleeves used for this purpose are provided in the region of the sleeve jacket with apertures, in order to allow a dye liquor to flow through the sleeves and the yarn package wound thereon from the inside outwardly and/or conversely. For this dyeing process, several bobbins are set onto a dye or liquor lance and are pressed against one another in the region of the front surfaces of the sleeve, in order to be able to allow the dye liquor in each case to flow through several bobbin bodies stacked one above the other. After conclusion of the dyeing process, the yarn is then dried and then rewound in a further rewinding process to form the bobbins intended for the end consumption.
Each rewinding of the yarn causes the yarn or respectively the thread to become hairier, which is undesirable for many kinds of yarn, more especially for sewing thread.
USPTO Backgrounds
USPTO Backgrounds