METHOD FOR CALIBRATING A THREAD STORAGE UNIT

Abstract

A method for calibrating a thread storage unit that can be arranged at a workstation of a textile machine. The method comprises the calibration steps of: setting of a calibration torque of the electric motor in the control system, wherein the calibration torque is lower than the maximum torque acting on the thread guide arm due to the magnetic repelling effect of the coupling elements; activation of the electric motor of the drive unit for adjusting the thread guide arm with the calibration torque to a rest position against a stop of the thread guide unit by the control system; and storage of the set position of the thread guide arm and the electric motor as the zero position of the thread guide arm and the electric motor in the control system.

Claims

1. A method for calibrating a thread storage unit that can be arranged at a workstation of a textile machine, the method comprising: mounting a thread guide arm in a manner freely rotatable about a pivot axis with a magnetically acting first coupling element arranged at a distance from the pivot axis; providing a drive unit having a controllable electric motor for reversibly pivoting the thread guide arm, wherein the drive unit has a second magnetic coupling element that is arranged so as to be adjustable relative to the first coupling element, acts in a magnetically repelling manner on the first coupling element and is arranged on the drive unit so that the drive unit can be brought into operative connection with the first coupling element, wherein an adjustment of the second coupling element in a direction of the first coupling element causes a displacement of the first coupling element in the same direction; detecting a rotational movement and/or position of the thread guide arm with a sensor unit; assigning a control system to the workstation for controlling the drive unit and for evaluating sensor information for identifying a thread tension exerted on a thread; setting of a calibration torque of the controllable electric motor in the control system, wherein the calibration torque is lower than a maximum torque acting on the thread guide arm due to a magnetic repelling effect of the first coupling element and the second coupling element; activating the controllable electric motor of the drive unit for adjusting the thread guide arm with the calibration torque to a rest position against a stop of the thread storage unit by the control system; and storing a set position of the thread guide arm and the controllable electric motor as a zero position of the thread guide arm and the controllable electric motor in the control system.

2. The method for calibrating according to claim 1, wherein the calibration torque is set such that the first coupling element and the second coupling element have a distance of 1 to 6 mm in the rest position.

3. The method for calibrating according to claim 1, wherein, prior to carrying out calibration, the thread storage unit is mounted at the workstation.

4. A workstation of a textile machine comprising: a thread storage unit; a thread guide arm mounted in a manner freely rotatable about a pivot axis with a magnetically acting first coupling element arranged at a distance from the pivot axis; a drive unit having a controllable electric motor for reversibly pivoting the thread guide arm, wherein the drive unit has a second magnetic coupling element that is arranged so as to be adjustable relative to the first coupling element, acts in a magnetically repelling manner on the first coupling element and is arranged on the drive unit so that the drive unit can be brought into operative connection with the first coupling element, wherein an adjustment of the second coupling element in a direction of the first coupling element causes a displacement of the first coupling element in the same direction; a sensor unit for detecting the rotational movement and/or position of the thread guide arm; and a control system assigned to the workstation for controlling the drive unit and for evaluating sensor information for identifying a thread tension exerted on the thread; wherein the control system is designed to carry out the method according to claim 1.

5. The workstation according to claim 4, wherein the thread storage unit is arranged at the workstation such that the thread guide arm is arranged in the rest position in a position crossing a thread running path, into which position the thread guided by the thread guide arm is pushed out of the thread running path during a bobbin travel.

Description

[0030] An exemplary embodiment of the invention is explained below with reference to the drawings. In the drawings:

[0031] FIG. 1 shows a perspective schematic view of a thread storage unit according to an exemplary embodiment;

[0032] FIG. 2 shows a perspective schematic view of an enlarged representation of a partial region of the thread storage unit of FIG. 1;

[0033] FIG. 3 shows a perspective schematic view of an enlarged representation of the thread storage unit of FIG. 1 without a thread guide arm,

[0034] FIG. 4 shows a perspective schematic representation of the thread guide arm of the thread storage unit of FIG. 1, and

[0035] FIG. 5 shows a schematic perspective view of the thread storage unit shown in FIG. 1 in an arrangement upstream of the paraffin application device.

[0036] FIG. 1 shows a perspective schematic view of a thread storage unit 1 according to an exemplary embodiment which is connected to a connection plate 17 for arrangement at a workstation, in particular, a spinning or winding station of a textile machine (not shown here). FIGS. 2 to 4 show a perspective schematic view of an enlarged representation of a partial region of the thread storage unit 1 shown in FIG. 1, and a perspective schematic representation of a thread guide arm 2 of said thread storage unit 1.

[0037] The thread storage unit 1 has a thread guide arm 2, which is arranged at the workstation with a thread guide eye 13 arranged at its free end in the thread running path F of a thread to be wound onto a run-on bobbin, wherein the thread is guided through the thread guide eye 13. In order to form a thread storage, the thread guide arm 2 is mounted pivotably on a drive shaft 16 of an electric motor 5 of a drive unit 4 of the thread storage unit 1, wherein for this purpose, the thread guide arm 2 has a bushing 18 for arrangement on the free end of the drive shaft 16, so that the thread guide arm 2 is mounted on the drive shaft 16 in a torque-free manner. The bushing 18 is furthermore connected to a holder 9 connected to the thread guide arm 2, which holder has an opening for receiving a first coupling element 6 designed as a permanent magnet.

[0038] The drive shaft 16 of the electric motor 5 is non-rotatably connected to a coupling disk 14, which is arranged coaxially to the drive shaft 16 for the thread guide arm 2 to pivot to form a loop during operation. A support 8, which has a further bushing 12 for receiving a further permanent magnet as the second coupling element 7, is arranged on the coupling disk 14. The permanent magnets on the thread guide arm 2 and the support 8 are oriented relative to each other such that they exert a magnetic repelling effect on each other. A rotation of the coupling disk 14 via the reversing electric motor 5 thus causes a corresponding contact-free pivoting of the thread guide arm 2 about the drive shaft 16, which defines a pivot axis S, wherein the electric motor 5 is controlled via a control system (not shown here) via the connection 19.

[0039] A sensor unit 3 arranged abovein relation to the drawingthe drive shaft 16 on a housing cover 11 of the housing 10 serves to detect the position of the thread guide arm 2, and is arranged with its sensor detecting the pivot angle coaxially to a connecting element 15 connected to the thread guide arm 2, which in turn extends in the longitudinal axis direction of the drive shaft 16.

[0040] The sensor unit 3 can be used to particularly reliably determine at least the rotational movement or the position of the thread guide arm 2, and to detect deviations of the thread guide arm 2 from the position set by the drive unit 4 by transmitting corresponding sensor information about the above to the control system. If, for example, the thread tension increases, then this causes a displacement of the thread guide arm 2 in the direction of the second coupling element 7 against the spring force generated by the magnetic repelling effect. On the basis of this, a return displacement of the coupling disk 14 can then take place via the control system. If, for example, the thread tension decreases while a thread is sagging, then this causes a displacement of the second coupling element 7 through a rotation of the drive shaft 16 and the support 8 coupled thereto together with the coupling disk 14 and the permanent magnet in the direction of the thread guide arm 2. Due to the magnetic repelling effect, the thread guide arm 2 is moved in the same direction, whereby the guided thread is pushed out of its thread running path F or further away therefrom, and a thread loop is formed or enlarged. A substantially constant thread tension can thus be achieved and ensured during the entire winding process or bobbin travel.

[0041] FIG. 5 shows a schematic perspective view of an exemplary embodiment of an arrangement of the thread storage unit 1 at the workstation (not shown), wherein the workstation can be a spinning or winding station. The thread storage unit 1 is arranged along a thread running path F, which runs from a thread feed device (not shown) in the direction of a traversing device (not shown) upstream of a paraffin application device 20, which is arranged upstream of the traversing device along the thread running path F and is only shown schematically and in excerpts. The paraffin application device 20 has a holder 22 underneath on which two thread guide rollers 21 are rotatably held, via which the thread can be guided along the thread running path F in a partially wrapped manner. The thread storage unit 1 is positioned on the thread running path F such that the thread guide arm 2 can pivot into the thread running path F with its guide eye 13 in order to push the running thread out of its thread running path F transverse to the direction in which the thread guide rollers 21 are arranged. As a result of being pushed out of its thread running path F by the thread storage unit 1, the thread comes into contact with the thread guide rollers 21, as a result of which a thread loop of a defined size is formed between the thread guide rollers 21. The size of the thread loop is varied as required by means of the thread storage unit 1 depending on the detected rotational movement or position of the thread guide arm 2 via the control system, which controls the electric motor 5 and consequently the thread guide arm 2, for setting and regulating a thread tension that is advantageously kept constant for the bobbin travel.

[0042] To calibrate the thread storage unit 1, a calibration torque of the electric motor 5 is set via a control system (not shown here), or a calibration torque stored in the control system or in a memory unit connected to the control system is selected. The calibration torque is such that the thread guide arm 2 is brought into contact with the inner side of the housing 10 by subsequently activating the electric motor 5 with the calibration torque. In the rest position of the thread guide arm 2 that is then set, the first coupling element 6 is also located at a distance from the second coupling element 7. The position of the thread guide arm 2 and the electric motor 5 is therefore determined solely by the calibration torque applied by the electric motor 5 and the magnetic forces acting between the coupling elements 6, 7. The setting position of the electric motor 5 and the thread guide arm 2 in the rest position are stored in the control system as the zero position of the thread guide arm 2 and the zero position of the electric motor 5.

[0043] Taking into account a known characteristic curve of the magnetic spring force previously stored in the control system or in a read-out memory unit coupled to the control system, the control system can be used to infer the thread tensile force acting on the thread and consequently the thread tension, taking into account the position of the thread guide arm 2 and the electric motor 5. The calibration of the thread storage unit 1 of a textile machine with a plurality of workstations ensures reliable detection of the correct thread tension for all workstations.

LIST OF REFERENCE SIGNS

[0044] 1 Thread storage unit [0045] 2 Thread guide arm [0046] 3 Sensor unit [0047] 4 Drive unit [0048] 5 Electric motor [0049] 6 First coupling element [0050] 7 Second coupling element [0051] 8 Support [0052] 9 Holder [0053] 10 Housing [0054] 11 Housing cover [0055] 12 Further bushing [0056] 13 Thread guide eye [0057] 14 Coupling disk [0058] 15 Connection element [0059] 16 Drive shaft [0060] 17 Connection plate [0061] 18 Bushing [0062] 19 Connection [0063] 20 Paraffin application device [0064] 21 Thread guide roller [0065] 22 Holder [0066] F Thread running path [0067] S Pivot axis