An air jet spinning machine, air jet spinning machine for producing a thread from a fed sliver, and method for detecting a thread strength, which falls below a target value, of a thread produced at a spinning unit of an airjet spinning machine are provided. A thread manipulation unit is arranged in the region between the airjet spinning machine and the spooling device, which thread manipulation unit acts mechanically on the thread and exerts an adjustable thread tension influencing force, in particular an adjustable braking force, compression force and/or clamping force, onto the thread in order to variably increase thread tension. In the method, an adjustable thread tension influencing force is exerted onto the thread, and a thread breakage and/or thread breakage rate are/is detected and compared with a specified target rate, and thread breakage and/or deviations of thread breakage rate beyond a predetermined limit value are displayed and/or evaluated.

An air jet spinning machine, air jet spinning machine for producing a thread from a fed sliver, and method for detecting a thread strength, which falls below a target value, of a thread produced at a spinning unit of an airjet spinning machine are provided. A thread manipulation unit is arranged in the region between the airjet spinning machine and the spooling device, which thread manipulation unit acts mechanically on the thread and exerts an adjustable thread tension influencing force, in particular an adjustable braking force, compression force and/or clamping force, onto the thread in order to variably increase thread tension. In the method, an adjustable thread tension influencing force is exerted onto the thread, and a thread breakage and/or thread breakage rate are/is detected and compared with a specified target rate, and thread breakage and/or deviations of thread breakage rate beyond a predetermined limit value are displayed and/or evaluated.

A yarn accumulator unit for a workstation with a yarn guide arm pivotally mounted about a pivot axis, and a controllable drive unit for reversing pivoting of the yarn guide arm. The yarn guide arm is to be freely rotatably mounted and to have a magnetically acting first coupling element arranged at a distance from the pivot axis, and for the drive unit to have a second magnetic coupling element arranged so as to be adjustable transversely to the first coupling element or about the pivot axis, magnetically repulsively acting on the first coupling element, which second magnetic coupling element is arranged so that it can be brought into active connection with the first coupling element on the drive unit, in which case an adjustment of the second coupling element in the direction of the first coupling element causes a displacement of the first coupling element in the same direction.

A yarn accumulator unit for a workstation with a yarn guide arm pivotally mounted about a pivot axis, and a controllable drive unit for reversing pivoting of the yarn guide arm. The yarn guide arm is to be freely rotatably mounted and to have a magnetically acting first coupling element arranged at a distance from the pivot axis, and for the drive unit to have a second magnetic coupling element arranged so as to be adjustable transversely to the first coupling element or about the pivot axis, magnetically repulsively acting on the first coupling element, which second magnetic coupling element is arranged so that it can be brought into active connection with the first coupling element on the drive unit, in which case an adjustment of the second coupling element in the direction of the first coupling element causes a displacement of the first coupling element in the same direction.

The invention relates to a drum intermediate storage of yarn for a textile machine having a driven rotary drum with a working surface and a movable radial rotary arm. The driven rotary drum is coupled with a first drive and the arm is coupled with a second drive, whereby both drives are composed of motors and both motors are connected to a control system of the textile machine. The radial rotary arm is provided with a yarn guide, whose working portion upholds the yarn radially relative to the axis of rotation of the drum.

A device as well as a method for determining the diameter of a yarn balloon (B) formed by a continuous yarn at a workstation (1) of a yarn balloon forming textile machine. The workstation (1) comprises an electromagnetically functioning sensor means (33), designed and arranged in such a way that at least two interruptions of a measuring beam (42) of the sensor means (33) are caused by the yarn (5, 25) forming the yarn balloon (B) during every rotation of the yarn balloon (B) during the operation of the workstation (1), and in that the time interval between the interruptions of the measuring beam (42) can be recorded by the sensor means (33) and used for calculating the diameter of the yarn balloon (B).

Process to set the optimal working height between the thread entry point and the thread exit point in a twisting and/or thread spinning machine, and a twisting and/or thread spinning machine that applies such process including: identifying the variation of tension of the thread produced by the variation of the winding diameter (d) of the thread (8) on the bobbin (5), depending on the position of the rocker (6), or the winding diameter of the thread on the bobbin (5); carrying out the displacements from the thread entry point (PE) and/or from the thread exit point (PS) to obtain a distance (LB) between both in which the variations of tension counter each other.

Yarn-tension influencing device for a twisting or cabling machine for feeding a yarn via a traversing yarn guide to a take-up package, the yarn-tension influencing device having a first deflection roller, arranged downstream of a yarn handling device in the yarn transport direction and is provided for guiding the yarn from a balloon yarn guide through the yarn handling device and for deflecting the yarn; a second deflection roller, arranged downstream of the first deflection roller in the yarn transport direction and is provided for further deflection of the yarn; a third deflection roller, arranged downstream of the second deflection roller in the yarn transport direction and is provided for adjusting the angle of wrap of the yarn around an advance roller; and an advance roller, arranged downstream of the third deflection roller in the yarn transport direction and is provided for regulating the yarn tension. The yarn handling device is a yarn clamping and cutting device, and a sensor device is provided for monitoring the yarn, the second deflection roller being arranged on a plane different from a horizontal plane formed by the axis of rotation of the first deflection roller.

A method of controlling a yarn compensating arm at a workstation of a spinning machine, wherein the yarn is initially withdrawn from an intermediate vacuum storage device. Before emptying the yarn from the storage device, the compensating arm is deflected past its working and into an out-of-the-working-range position, wherein the yarn is captured by the compensating arm and also deflected to the out-of-the-working-range position to form a non-working yarn reserve. The compensating arm is retained by a force at the out-of-the-working-range position while the yarn is emptied from the storage device. Upon being emptied from the intermediate vacuum storage device, the yarn exerts a tensile force on the compensating arm that overcomes the retaining force causing the compensating arm to return to its working range position.

A method for automatically piecing a thread at a workstation of a textile machine, includes seeking an end of the thread on a surface of a bobbin with a suction nozzle and unwinding the thread from the bobbin counter to a regular draw-off direction of the thread and sucking the thread into the suction nozzle. The bobbin is driven in a direction of reverse rotation with a drive. A thread loop is draw-opened in the thread and moved towards a piecing unit via movement of a feeder unit. The bobbin is driven in the direction of reverse rotation during the drawing-open of the thread loop such that the thread is unwound from the bobbin. A speed of reverse rotation of the bobbin is coordinated with movement of the feeder unit.