Optimization of the operation of a spinning machine

Abstract

A method for optimizing the operation of a spinning machine with regard to quality and productivity is provided. An apparatus, comprising a control device and the spinning machine is provided. A yarn having specified yarn properties is produced, a quality parameter of the yarn is sensed during the spinning operation, a parameter for setting the production speed is specified, the quality parameter and the parameter for setting the production speed are evaluated, and the production speed is set in dependence on a target variable, the target variable comprising the quality parameter.

Claims

1. A method for optimizing the operation of a spinning machine with regard to quality and productivity, the method comprising: producing a yarn having a specified yarn property; sensing during the spinning operation a quality parameter of the yarn, which quality parameter is a measure of a deviation from the specified yarn property, and wherein an upper limit value and a lower limit value for the quality parameter are specified; specifying a parameter for setting a production speed; evaluating the quality parameter and the parameter for setting the production speed; and setting the production speed in dependence on a target variable, the target variable comprising the quality parameter.

2. The method according to claim 1, characterised in that a yarn break rate is sensed and evaluated and the target variable comprises the yarn break rate.

3. An apparatus comprising a control device and a spinning machine, for producing a yarn having a specified yarn property, for sensing a quality parameter of the yarn during the spinning operation, which quality parameter is a measure of a deviation from the specified yarn property, and wherein an upper limit value and a lower limit value for the quality parameter are specified, and for specifying a parameter for setting the production speed, the control device being designed to evaluate the quality parameter and the parameter for setting a production speed, and the control device being designed in such a way that the production speed is set by the control device in dependence on a target variable, the target variable comprising the quality parameter.

4. The apparatus according to claim 3, characterised in that the control device is designed to evaluate a yarn break rate, and the target variable comprises the yarn break rate.

5. The apparatus according to claim 3, characterised in that the control device comprises a user interface, on which the parameter for setting the production speed and the target variable are simultaneously displayed.

6. The apparatus according to claim 3, characterised in that the control device is designed to display a time curve of the parameter for setting the production speed and of the target variable.

7. The apparatus according to claim 3, characterised in that a limit value for the target variable can be specified to the control device.

8. The apparatus according to claim 3, characterised in that the control device is designed to determine proposals for a change to the parameter for setting the production speed.

9. The apparatus according to claim 3, characterised in that the control device is designed to create and store data sets, which comprise the specified yarn property, the parameter for setting the production speed, and the associated target variable.

10. The apparatus according to claim 9, characterised in that the control device is designed to compare the data sets with the specified yarn property and with a specified limit value for the target variable and to select a data set for the operation of the spinning machine in accordance with the comparison.

11. The apparatus according to claim 10, characterised in that the control device has an interface for editing the selected data set.

12. The apparatus according to claim 11, characterised in that the control device is designed to apply and store the edited data set.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention is explained in greater detail below on the basis of an embodiment example. The figures show:

(2) FIG. 1 illustrates a user interface for performing the optimization according to the invention;

(3) FIG. 2 illustrates a display of the time curve of the parameter for setting the production speed and of the target variable;

(4) FIG. 3 is a schematic illustration of the optimization in accordance with the principle of case-based reasoning.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

(5) The following description of the embodiments of the present invention is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses. The following description is provided herein solely by way of example for purposes of providing an enabling disclosure of the invention, but does not limit the scope or substance of the invention.

(6) FIG. 1 shows a user interface of a control device, by means of which the operator of the spinning machine can set the production speed in dependence on a target variable. In the embodiment example, the target variable comprises a quality parameter, namely a CV value, and the yarn break rate (“Yarn breaks”). The CV value is indicated in %. The embodiment example relates to an open-end rotor spinning machine.

(7) The user interface initially contains indications that allow conclusions to be drawn about the yarn properties. The lot name is displayed in field 1, the lot number is displayed in field 2, the yarn number is displayed in field 3, and the work area is displayed in field 4. The work area indicates the spinning positions for which the optimization is performed. By indicating the lot number and the lot name, traceability of additional machine parameters and production parameters relevant to the yarn properties is ensured at all times.

(8) The observation time that should be used for the optimization can be indicated in field 5. The remaining time is indicated in field 6. A reference rotational speed for the spinning rotor can be indicated in field 9. Furthermore, a step size (“Delta Rotor Speed”) with which the rotor rotational speed is changed for optimization can be indicated in field 7. The upper limit (“max”) for the yarn break rate is indicated in field 14. Field 16 allows a lower limit (“min”) for the CV value to be input. The upper limit (“max”) of the CV value is specified in field 17.

(9) The optimization process is started by pressing the start button 10. The process can be interrupted or ended by pressing the stop button 11. The operation of the spinning machine starts initially with the reference rotational speed 9. The current rotor rotational speed is displayed in field 8. The ongoing production (“Production”) is displayed in field 12. That is, the metres of produced yarn are indicated. Furthermore, the current yarn break rate 13 and the CV value 15 are indicated. Directly adjacent, the specified limit values are indicated. The operator thus sees at a glance whether and to what extent the yarn break rate 13 and the CV value 15 are at a distance from the limits. The operator can then change the rotor rotational speed directly by means of the reference rotational speed 9 or at the press of a key, by the previously defined step size 7.

(10) In an alternative embodiment, the control device is designed to make proposals for a change to the rotor rotational speed. Such proposals can be displayed by means of a pop-up window, for example. An algorithm that calculates this proposal on the basis of the deviation of the yarn break rate 13 and the CV value 15 from the specified limit values 14, 16, 17 and on the basis of the step size 7 can be stored in the control device. Here, the operator again has the option of checking the proposal before the change to the rotor rotational speed is made.

(11) In order to facilitate the operator's decision about a change to the production speed, the time curve of the parameter for setting the production speed and of the target variable can advantageously be graphically displayed. FIG. 2 shows such a graphical display, again using the example of an open-end rotor spinning machine. A CV value is displayed as the target variable.

(12) FIG. 2 shows, accordingly, the curve 20 of the CV value and the curve 21 of the rotor rotational speed over time (“Time”). The lower limit 18 and the upper limit 19 for the CV value are also displayed. At the start of the observation, the CV value lies within the assigned limits, but only just above the lower limit 18. Therefore, in this case there is the possibility of increasing the rotor rotational speed and raising the productivity. The rotor rotational speed is increased in several steps. The CV value increases until the upper limit 19 is exceeded. The rotor rotational speed is lowered again by the amount of the step performed last. Thus, an optimized working point that has a higher production speed is found, but the CV value still lies within the specified limits.

(13) FIG. 3 illustrates an optimization of the operation of a spinning machine with regard to quality and productivity using the principle of case-based reasoning. The process occurs largely automatically and is performed by the control device according to the invention, which, for example, comprises a chip having artificial intelligence.

(14) The starting point for the optimization is a case base or a database 22. This database 22 contains a plurality of data sets 23 having optimized operating points of one or more spinning machines under specified conditions. For this purpose, the data sets 23 contain the specified yarn properties, the parameter for setting the production speed, and the resulting target variable. Reference sign 24 defines specified conditions under which the operation of a spinning machine should be optimized. The specified conditions 24 comprise at least the specified yarn properties and a specified limit value for the target variable. The conditions 24 are then compared with the data sets 23, and the data set 22 closest to the conditions 24 is selected (“Retrieve”). The data set 25 results therefrom. By applying this data set 25 under the specified conditions, the applied data set 26 is obtained (“Reuse”). Up to this point, the described method is preferably carried out automatically by the control device. The control device preferably has an interface, which enables editing by the operator (“Revise”). Thus, the data set 27 is obtained, which finally is received into the database 22 as data set 28 (“Retain”). In this way, the control device learns and can draw on a larger database 22 for future optimizations.

(15) It will therefore be readily understood by those persons skilled in the art that the present invention is susceptible of broad utility and application. Many embodiments and adaptations of the present invention other than those herein described, as well as many variations, modifications and equivalent arrangements, will be apparent from or reasonably suggested by the present invention and the foregoing description thereof, without departing from the substance or scope of the present invention. Accordingly, while the present invention has been described herein in detail in relation to its preferred embodiment, it is to be understood that this disclosure is only illustrative and exemplary of the present invention and is made merely for purposes of providing a full and enabling disclosure of the invention. The foregoing disclosure is not intended or to be construed to limit the present invention or otherwise to exclude any such other embodiments, adaptations, variations, modifications and equivalent arrangements.