Abstract: An Apparatus is described for the propagation of the rotary twisting of an open-end yarn from a yarn section in a thread guide to the entwinement point of an open-end spinning apparatus with a spinning element. A provision is made in the longitudinal extent of the thread guide for a thread contact surface, to which surface a vibration element is supplied. The thread contact surface possesses a polished surface and is part of an inlet element on the thread inlet end of the thread guide. The vibration element is connected to a control system, with the aid of which the frequency and/or the amplitude of the vibration generated by the vibration element can be made to match the current operational phase.

Abstract: The present invention relates to a process for the control of the piecing process in a spinning device, in particular an open-end spinning device with rotors, as well as to a device to carry out the process. It is the object of the present invention to make it possible to trigger the piecing process without having to change the structure of the rotor or of the bearing disks of a spinning device. This problem is solved in that the piecing process is carried out and/or controlled in function of physical magnitudes or states and/or their changes in a spinning device. According to the invention, the device is provided with a measuring device to detect physical magnitudes connected with the control of the piecing process.

Abstract: For the propagation of the rotary twisting from a thread section (Gb) in a thread guide (2) into the entwinement point (E) of an open-end spinning apparatus with a spinning element (10) provision is made in the longitudinal extent of the thread guide (2) for a a thread contact surface (41), to which surface a vibration element (40, 40a, 40b, 40c, 40d) is supplied. The thread contact surface (41) possesses a polished surface and is part of an inlet element (21) on the thread inlet end of the thread guide (2). The vibration element (40, 40a, 40b, 40c, 40d) is connected to a control system (5), with the aid of which the frequency and/or the amplitude of the vibration generated by the vibration element (40, 40a, 40b, 40c, 40d) can be made to match the current operational phase and/or the current rotational speed of the spinning element (10) and/or the fiber material to be worked.

Abstract: A spinning rotor for an open-end spinning device is proposed which is provided with a smooth surface at the critical locations in order to avoid deposits within the spinning rotor at its inner surface. The ring-shaped zone of the inner surface of the spinning rotor near its edge as well as the area of its bottom may for instance be made especially smooth by polishing.

Abstract: The instant invention relates to a process and device for piecing on an open-end spinning device. Before the beginning of the piecing process the desired run-up curve for the fiber stream which is to be fed to the fiber collection surface and the acceleration curve of the fiber feeding device corresponding to this run-up curve are defined. During piecing the fiber feeding device is switched on and is driven in accordance with the defined acceleration curve. The fiber stream produced thereby is deflected and removed on its way between the fiber feeding device and a fiber collection surface. In this process the current actual values are calculated from the acceleration curve of the fiber feeding device and the fiber stream is again fed to the fiber collection surface when a predetermined desired value has been reached, before the fiber stream which is started by switching on the fiber feeding device has reached its full strength.

Abstract: A process and device to detect and count yarn defects in a yarn segment including a camera (5), a computer (8) and an image processing program. The yarn (30) is illuminated with an intensity dependent upon the thickness of the yarn (30) and is photographed by the camera (5). The photographed image is digitalized in the computer with the image processing program and low-contrast points are filtered out. The remaining points are gathered together into coherent areas the sizes of which are classified into predetermined size classes and are stored.