Workstation of a Rotor Spinning Machine Comprising a Cleaning Unit and Method for Operating Such a Device

Abstract

The invention relates to a workstation of a rotor spinning machine including a spinning rotor (3) mounted so as to be rotatable about a rotational axis (X), wherein the workstation comprises a cleaning unit (1) including a mechanical cleaning element (2) for cleaning an inner surface (21) of the spinning rotor (3). According to the invention, it is provided that the cleaning element (2) is movably arranged on the workstation in such a way that, starting from a neutral position in which the cleaning element (2) is not in contact with the spinning rotor (3), the cleaning element (2) can be moved into various cleaning positions for various inner diameters of the spinning rotor (3), wherein the cleaning element (2), in the particular cleaning position, is in contact with the inner surface of the spinning rotor (3).

Claims

1. A workstation of a rotor spinning machine including a spinning rotor (3) mounted so as to be rotatable about a rotational axis (X), wherein the workstation comprises a cleaning unit (1) including a mechanical cleaning element (2) for cleaning an inner surface (21) of the spinning rotor (3), characterized in that the cleaning element (2) is movably arranged on the workstation in such a way that, starting from a neutral position in which the cleaning element (2) is not in contact with the spinning rotor (3), the cleaning element (2) can be moved into various cleaning positions for various inner diameters of the spinning rotor (3), wherein the cleaning element (2), in the particular cleaning position, is in contact with the inner surface of the spinning rotor (3).

2-21. (canceled)

Description

[0048] Further advantages of the invention are described in the following exemplary embodiments. Wherein:

[0049] FIG. 1 shows a side view of a spinning rotor comprising a cleaning unit in the neutral position,

[0050] FIG. 2 shows a side view of a spinning rotor comprising a cleaning unit during the insertion/withdrawal,

[0051] FIG. 3 shows a side view of a spinning rotor comprising a cleaning unit in the cleaning position,

[0052] FIG. 4 shows a top view of a spinning rotor comprising a cleaning unit,

[0053] FIG. 5 shows a side view of a cleaning unit,

[0054] FIG. 6 shows a side view of a cleaning unit, and

[0055] FIG. 7 shows a side view of a cleaning unit.

[0056] In the following description of the figures, the same reference signs are utilized for features which are identical and/or at least comparable in each of the various figures. The individual features, their embodiment and/or mode of operation are explained in detail usually only upon the first mention thereof. If individual features are not explained in detail once more, their embodiment and/or mode of operation correspond/corresponds to the embodiment and mode of operation of the features which act in the same way or have the same name and have already been described.

[0057] FIGS. 1, 2, and 3 schematically show a sectional view, as an example, of an embodiment variant, according to the invention, of a workstation comprising a cleaning unit 1 and a spinning rotor 3. The representation omits all other attachments of a workstation, such as a sliver feed unit, since appropriate workstations of a rotor spinning machine are known, in principle, from the related art. The spinning rotor 3 is rotated about the axis X during the operation of a central or single drive, wherein the rotational speed is controlled by a spinning machine control system (not represented) or a workstation-specific control system. After the sliver has been moved through a sliver feed unit (not represented) into the opening roller (also not represented), the individual fibers enter the spinning rotor 3 in which they impact the rotor groove 4 rotating at high speed. Due to the geometry of the spinning rotor 3 and its speed, the fibers are spun into a yarn.

[0058] In this spinning process, it is unavoidable that foreign material and other fiber reside accumulate in the spinning rotor 3. The level of contamination increases sharply after a certain period of operation, primarily in the rotor groove 4. Therefore, the quality of the spun yarn decreases or thread breakages occur already in the spinning rotor 3. For this reason, the rotor groove 4 must be cleaned at regular intervals. This is possible due to the represented cleaning unit 1.

[0059] If a cleaning process is necessary, the appropriate control system reduces the rotational speed of the spinning rotor 3 and opens a closure (not represented) of a spin box enclosing the rotor. Additionally, the control system actuates the drive 12, 13, 14, 15 of the cleaning unit 1, in order to start the cleaning process.

[0060] In the present exemplary embodiment, the cleaning unit 1 comprises a cleaning element 2, a first drive 12, 13, and a second drive 14, 15.

[0061] In the present example, the cleaning element 2 is divided into four regions. The first region 8 of the cleaning element 2 is utilized as a fastening means for mounting on the first drive 12. The second region 9 and the third region 10 are designed to be linear in this case and extend, with respect to FIGS. 2 and 3, horizontally (second region 9) from the first region and then vertically (third region 10) to the fourth region 11. The fourth region 11 is the tip of the cleaning element 2, with the aid of which the cleaning element 2 can be brought into contact with the spinning rotor 3. All four regions 8, 9, 10, 11 or any combination of one or multiple regions 8, 9, 10, 11 can be made of an elastic material.

[0062] The first drive 12 comprises an electric motor, for example, a stepper motor 15, with the aid of which the cleaning element 2 is mounted so as to be rotatable about the rotational axis Y, which preferably extends in parallel to the rotational axis X of the spinning rotor 3. The first drive 12 can therefore swivel the cleaning element 2 perpendicularly to the rotational axis X of the spinning rotor 3.

[0063] In this context, it is also feasible, of course, that the rotational axis X of the spinning rotor 3 and the rotational axis Y of the cleaning element 2 extend askew with respect to one another. The second drive 13 comprises a linear drive 14, for example, in the form of a double-acting pneumatic cylinder. The double-acting pneumatic cylinder can change the height offset between the cleaning element 2 and the spinning rotor 3, in order to ensure a problem-free insertion of the cleaning element 2 into the spinning rotor 3. The height offset of the cleaning element 2 must be at least as great as the greatest height offset between the normal position of the cleaning element 2 and the upper edge of the spinning rotor 6.

[0064] In a first step after the spinning machine control system has started the cleaning process, the cleaning element 2 is raised by the linear drive to such an extent that the cleaning element 2 is located above the upper edge of the spinning rotor 6. In a second step, the cleaning element 2 is swiveled about the rotational axis Y by the stepper motor 15, so that the cleaning element 2, as viewed in the top view, comes to rest above the spinning rotor 3 (cf. also FIG. 4). In a third step, the linear drive 14 lowers the cleaning element 2 into the interior space 5 of the spinning rotor 3, in which the cleaning element 2 is brought into contact with the rotor wall 7 or the rotor groove 4 with the aid of a further swiveling process. Due to the fact that the spinning rotor 3 is still rotating, fixed foreign material is mechanically removed from the spinning rotor 3 with the aid of a scraping process. The rotational speed of the spinning rotor 3 can be held constant by the spinning machine control system during the cleaning process, although it can also be variably adapted (depending on the level of contamination). In so doing, the spinning machine control system can determine, for example, by reading out the motor parameters, i.e., the angular position of the cleaning element 2 and/or the voltage draw and the current draw, the extent to which the cleaning element 2 has been worn or whether errors occur during the cleaning.

[0065] After the trash has been removed from the rotor groove 4, loose foreign material can be additionally removed from the spinning rotor 3 with the aid of a suction and/or blowing device (not represented here) associated with the cleaning element 2. The movement of the cleaning element 2 back into the neutral position is carried out inversely with respect to the movement from the neutral position into the cleaning position.

[0066] A schematic top view of a workstation comprising a spinning rotor 3 and a cleaning unit 1 is represented in FIG. 4. The configuration of the cleaning unit 1 and the sequence of the cleaning are basically identical to the embodiment variant shown in FIGS. 1, 2, and 3. In the variant shown here, it would also be feasible, however, that the lifting mechanism, i.e., the pneumatic cylinder from FIGS. 1, 2, and 3, is replaced by way of positioning the two rotational axes, i.e., the rotational axis Y of the cleaning element 2 and the rotational axis X of the spinning rotor 3, askew with respect to one another. As a result, due to the rotational movement of the cleaning element 2, a height offset of the tip of the cleaning element 2 additionally results from the movement out of the neutral position into the cleaning position and back, whereby the cleaning element 2 can be moved, without contact, over the upper edge of the spinning rotor 3 or its rotor wall 7.

[0067] FIG. 5 and FIG. 6 show an embodiment variant of a cleaning unit 1 similar to the preceding description. In this case as well, the cleaning unit 1 comprises a cleaning element 2 and a first drive 12 according to the preceding figures. The difference from the preceding variants is that, in addition to a first rotational axis Y, a second rotational axis Z is also present. The height offset necessary for moving the cleaning element 2 over the upper edge of the spinning rotor 3, without contact, is achieved, in this case, via a swiveling about the second rotational axis Z. For this purpose, a second drive in the form of a linear drive 14 is associated with the cleaning unit 1, which swivels the cleaning element 2 and its first drive 12 about the second rotational axis Z with the aid of a retraction and an extension. The linear drive 14 preferably comprises a single-acting pneumatic cylinder including an energy accumulator associated with the pneumatic cylinder, wherein the energy accumulator preferably consists of a compression or tension spring (not represented).

[0068] FIG. 7 schematically shows a sectional view of a guide 16 for a cleaning unit 1 of a workstation of a spinning machine. In this exemplary embodiment, this guide 16 is designed as a slotted guide 17. A special drive for guiding the cleaning unit 1 with the aid of the gate 17 is not represented in this figure. In this example, the gate 17 is subdivided into three sections, wherein the first section 18 and the third section 20 are utilized for the horizontal guidance and the second (middle) section 19 is utilized primarily for the vertical guidance. In this way, with the aid of a single drive, the complete insertion and withdrawal movement of the cleaning element 2 can be implemented without dispensing with the adaptability with respect to the rotor diameter. The adaptation to the rotor diameter takes place via the holding point in the guide in the third section 20.

[0069] The present invention is not limited to the represented and described exemplary embodiments. Modifications within the scope of the claims are also possible, as is any combination of the features, even if they are represented and described in different exemplary embodiments.

LIST OF REFERENCE CHARACTERS

[0070] 1 cleaning unit [0071] 2 cleaning element [0072] 3 spinning rotor [0073] 4 rotor groove [0074] 5 interior space of the spinning rotor [0075] 6 upper edge of the spinning rotor [0076] 7 rotor wall [0077] 8 first region of the cleaning element [0078] 9 second region of the cleaning element [0079] 10 third region of the cleaning element [0080] 11 fourth region of the cleaning element [0081] 12 first drive [0082] 13 second drive [0083] 14 linear drive [0084] 15 stepper motor [0085] 16 guide [0086] 17 slotted guide [0087] 18 first section of the guide [0088] 19 second section of the guide [0089] 20 third section of the guide [0090] 21 inner surface [0091] X rotational axis of the spinning rotor [0092] Y rotational axis of the cleaning element [0093] Z second rotational axis