A process is provided of yarn spinning and/or twisting, in which a yarn runs between a yarn feeder towards a yarn picker. A driver rotates the yarn picker at a predetermined speed, in which a stretch of balloon is generated in a point located between the yarn feeder and the yarn picker by the presence of a ring. A helical path with oscillating spiral diameters exists between the yarn feeder and the yarn picker, so that the path of the yarn through the ring, creates a body of revolution from a diameter generating a balloon that has at least a hyperboloid structure forming at least two stretches of balloons consecutive to each other. A machine for performing the process is also provided.

A method for operating a workstation (1) of a yarn balloon forming textile machine, wherein a yarn balloon (B) formed by a continuous yarn (5) circling a spindle (2) of the workstation (1) is scanned with a sensor means (33) at said workstation. Data (D) recorded by the sensor means (33), providing information about the current diameter of the yarn balloon (B) to be monitored, is transmitted to a control circuit (18), in that the control circuit (18) calculates the current actual diameter of the yarn balloon (B) by means of this data (D) and further known data, compares this with a stipulated target diameter of the yarn balloon (B), and in that the control circuit (18) ensures that the yarn balloon (B) has the stipulated target diameter with the aid of a means (6) switched into the yarn path of the yarn (5), for influencing the yarn tension.

A process of yarn spinning and/or twisting, in which a yarn runs between a yarn feeding means (1) towards a yarn picking means is provided. A driving means rotates the yarn picking means at a predetermined speed, in which a stretch of balloon is generated in a point located between the feeding means (1) and the picking means by the presence of twisting means. A helical path with oscillating spiral diameters exists between the yarn feeding means (1) and the yarn picking means, so that the path of the yarn, by the operation of the twisting means, creates a body of revolution from a diameter generating a balloon that has at least a hyperboloid structure (E) forming at least two stretches of balloons (B) consecutive to each other. A machine for performing the process is also provided.

A device for determining the diameter of a yarn balloon (B) formed by a running yarn at a workstation (1) of a textile machine wherein the workstation (1) is provided with a mechanical, contact scanning sensor (22), which is designed and arranged so that during the operation of the workstation (1) it is positioned by a yarn forming the thread balloon (B) in an operating position dependent on the diameter of a thread balloon (B), and a sensor device (24) is provided which detects the operating position (BS) of the scanning sensor (22).

A device for determining the diameter of a yarn balloon (B) formed by a running yarn at a workstation (1) of a textile machine wherein the workstation (1) is provided with a mechanical, contact scanning sensor (22), which is designed and arranged so that during the operation of the workstation (1) it is positioned by a yarn forming the thread balloon (B) in an operating position dependent on the diameter of a thread balloon (B), and a sensor device (24) is provided which detects the operating position (BS) of the scanning sensor (22).