EP1295835B1 - Method for setting a clearing limit line in an electronic yarn clearer - Google Patents

Description

The invention relates to a method for setting a cleaning limit in an electronic yarn cleaner, wherein the possible yarn defects are arranged in a sorting scheme sorted by error value and error length and wherein the cleaning limit is selected by means of a curve and adjusted on Garnreiniger.

In a known method for setting the cleaning limit of electronic yarn cleaners (DE 40 20 330 C2), the yarn defects are arranged in a table in the manner of a coordinate system. One axis of the coordinate system represents the error cross section of the measured yarn and the other axis the error length. A cleaning limit is defined in this coordinate system with at least two points, whereby a predefined connecting line is drawn between the points as the course of the cleaning limit. Outside the outermost points, a predeterminable course of the cleaning limit is selected. In order to allow the most freely selectable course of the cleaning limit, it is necessary in this method to use a multiplicity of points and specify them in the coordinate system, which requires a complicated adjustment of the cleaning limit. If, on the other hand, only very few points are used, the adjustment of the cleaning limit can not be flexibly adapted by using the predetermined, defined connection line.

It is therefore an object of the invention to provide a method and an adjustment device for adjusting the cleaning limit in an electronic yarn cleaner, which allow a simple, fast and flexible setting of the cleaning limit.

This object is achieved with the features of claim 1 and 11, respectively.

In the method according to claim 1, the possible yarn defects are arranged sorted by error value and error length in a sorting scheme. A sorting scheme is, for example, a table, a table-type coordinate system, a coordinate system, or the like. Over the ranges of interest of error value and error length, the sorting scheme detects the possible yarn defects, so that the cleaning limit can be defined in the scheme. The cleaning limit then separates the tolerable errors of the yarn from the unacceptable errors. Preferably, after setting the cleaning limit during the running yarn inspection, the yarn cleaner issues an error message if the fixed yarn defect is above or below the cleaning limit or at the cleaning limit. Based on the error signal is z. B. in an open-end spinning machine causes the cutting of a thread section with the error. Or in the case of the produced yarn, the error and the error location are registered, so that an error statistic is created.

The error value is a measure of the size of the error. This can be, for example, the error cross section, for example, undershooting or exceeding a desired yarn cross section. Or the error value is a deviation from a predetermined target color, whereby the yarn is spectrally analyzed by a sensor. Or it registers the hairiness of the yarn currently being produced, whereby the density or number of fiber ends projecting from the thread is registered. Further examples of error values are an error mass, which can be detected, for example, with a capacitive sensor, impurity fractions, which is detected, for example, with an optical sensor by absorption and / or reflection, or the like.

The cleaning limit is determined by a curve by means of exactly one point in the sorting scheme, whereby the curve of the curve itself is arbitrary but defined. This makes a particularly quick and easy setting of the cleaning curve by the user of the electronic yarn cleaner possible.

In a particularly advantageous embodiment, the user is not only a fixed curve available, but he can select the optimal curve from a predetermined set of curves with different curves. This results in a fast and flexible adaptation of the cleaning limit to the desired course. Preferably z. For example, on a selection screen, the user may be presented with two or more of the selectable waveforms which he may select by simply entering a selection number or clicking with a pointer element.

Due to the scalability of the curve selected in this way, it is possible once again to influence the curve shape in order to optimally approximate the desired curve shape. Due to the scalability, any existing tolerances in the determination of the error length or the error value can be easily compensated. For example, if the error value or length determination has a relative error over the entire range. The error value and / or the error length are therefore advantageously scalable. When scaling, the curve is advantageously compressed or stretched by the scaling factor. Also by turning or tilting the curve is a simple adaptation of the curve to the desired course. The scaling is particularly advantageously carried out starting from the point with which the curve is determined in the sorting scheme.

Figur 1

die Festlegung einer Reinigungsgrenze in einem Koordinatensystem,

Figur 2

das Skalieren eines vorgegebenen Kurvenverlaufs,

Figur 3

einen Satz auswählbarer, vorgegebener Kurvenverläufe,

Figur 4

das Festlegen einer Reinigungsgrenze in einer Fehlertabelle,

Figur 5

das Festlegen von Farbbandspektren in einem Koordinatensystem und

Figur 6A und 6B

zwei Ausführungsformen von Garnreinigerstrukturen mit einer Einstelleinrichtung zum Einstellen der Reinigergrenze.

With reference to drawings embodiments of the invention will be explained in more detail. Show it:

FIG. 1

the definition of a cleaning limit in a coordinate system,

FIG. 2

the scaling of a given curve,

FIG. 3

a set of selectable, given curves,

FIG. 4

setting a cleaning limit in an error table,

FIG. 5

setting color band spectra in a coordinate system and

FIGS. 6A and 6B

two embodiments of Garnreinigerstrukturen with an adjustment for adjusting the cleaner limit.

In an open-end spinning machine, a ring spinning machine or a rewinding machine, the running yarn is drawn for thickness measurement through a measuring slot of a sensor in a known manner. The sensor registered z. B. optically the thickness or capacitive way the mass of the continuous yarn. Due to the known speed and the measured diameter of the yarn, the errors are classified according to the defect cross section and the defect length. This is z. B. also known from DE 40 20 330 C2. Within a tolerance range, the thus classified errors of the yarn continuously drawn through the sensor should be tolerated, ie the yarn corresponds to the desired quality. If, on the other hand, the classed errors lie outside this range, then these errors must be cut out of the yarn at a later processing stage or in the current processing stage by cutting become. The tolerable and the intolerable area are separated by a cleaning limit.

The setting of the cleaning limit according to the invention will be described below. The setting is carried out by selecting the course of the cleaning curve RG and the setting of the point P. Selection and setting can, for. B. done on an input device of the yarn cleaner. For this purpose, either a table or a coordinate system is displayed two-dimensionally on a screen. The setting and selection can also z. B. on a multi-line LCD display by entering the appropriate parameters. The input device can be an input device of the yarn cleaner or an input device, the z. B. is connected to the machine control of a textile machine. With the input device, the parameters are queried by appropriate software implementation and, if necessary, transmitted to the yarn cleaner after the input has been completed via a communication connection. For example, in an input device of the machine control of the textile machine, the data can be input and transmitted via a communication link to a section controller for several spinning stations. The section controller transmits the data to a yarn cleaner monitoring multiple spinning stations or to a yarn cleaner monitoring only one spinning station. Below, the input device and the input device will be described in detail with reference to FIGS. 6A and 6B.

In FIGS. 1 to 5, the selection and adjustment of the cleaning limit is shown in two-dimensional graphic for illustrative purposes. However, the appropriate setting and selection can also be easily entered using an alphanumeric parameterization and alphanumeric input on an input device.

FIG. 1 shows a diagram of yarn defects in which the length of the defect L is plotted on the x-axis and the diameter of the yarn defect is plotted on the y-axis. The standard value of the desired yarn diameter is φ _soll . The upper curve RG + indicates the upper cleaning limit, above which a yarn fault is cut out. The cleaning limit RG + is a curve selected from a set of predetermined waveforms (see FIG. 3). The position of the cleaning limit RG + is defined in the diagram by moving the setting point P +. The point P + can be shifted in the x and y axis direction. The curve of the cleaning limit RG + exceeds the lower limit of the yarn defect length L _min and exceeds the upper limit of the maximum yarn allowance L _{max considered} . However, only the curve within the limits L _min and L _{max is shown} . After setting the cleaning limit RG +, only the curve within these limits is considered in the electronic yarn cleaner for yarn cleaning. In addition to the setting of the cleaning limit, as shown in the diagram of Fig. 1, are set by own parameter queries the S and L channel for the yarn cleaning. These affect thick and thin areas and are adjusted in a conventional manner.

Further, Figure 1 shows the setting of the lower cleaning limit RG-, which is set according to the upper cleaning limit RG +. Again, the curve of the lower cleaning limit RG- from a variety of different curves (not shown) is selected and fixed in the diagram by moving the point P-:

After selecting the course of the cleaning curve and the fixing point P of the cleaning curve, if necessary, a scaling of the cleaning curve is carried out, as shown in FIG. This can affect both the upper purification curve RG + and the lower purification curve RG- accordingly. The basic curve shape RG ₀ can be determined by a factor in the x-direction stretched or compressed. For example, the cleaning limit RG _{x is} obtained by stretching the basic form RG ₀ . Furthermore, the cleaning curve can be stretched or compressed by a factor in the y-direction. In FIG. 2, the cleaning limit RGy is generated by stretching the basic curve shape RG ₀ . In addition, a tilted cleaning limit RG _{φ is} obtained when the cleaning basic shape RG ₀ is rotated by an angle φ. The stretching and / or tilting takes place in FIG. 2 about the setting point P, but can optionally be set with reference to any point of the diagram or the basic form RG ₀ out.

FIG. 3 shows different, selectable curves of the cleaning limit. For example, in the case of the curve RG ₀ , the tolerance for large cross-sectional errors is set relatively large up to the lower third of the maximum length. The further course is approximately stepped, with transitions between the stages. With curve RG ₁ , large thickness errors are tolerated only up to a small length range and then also the error classes are gradually reduced, whereby here ramped transitions are selected. For the RG ₂ curve, large error cross-sectional deviations are tolerated up to the mean error length, until a continuous transition to a small fault cross-section takes place at long lengths. In the course of the curve RG ₃ again thick cross-sectional defects are tolerated only up to very short lengths.

The curve RG _C is a customer-defined curve, which can be individually specified and is also selectable as a selection option under the curves. In the case of this curve RG _C , a larger error diameter is tolerated in the middle length range than immediately left and right of this length range. This setting is useful, for example, if production-related in this length range is very often a larger error cross-section and not constantly production should be stopped because of this error occurs. In contrast, lies in the middle range over all lengths a tolerable result including the average error lengths before, so that overall, even with this error, the average error specifications are observed. Conventionally, however, the course of the upper (lower) cleaner boundary is only falling (rising) or sectionally constant, since a fault in a fabric is all the more conspicuous the longer the yarn defect is.

FIG. 4 illustrates the entry of the cleaning limit on the basis of a curve RG ₀ in a tabular error classification. In this tabular error classification, this is not done continuously as in the diagram of FIG. 1, but rather discrete error classes are defined, each of which summarizes a specific range of error lengths and error diameters. In this case, the curve RG _{0 is} also fixed with the set point P + within the tabular matrix and then converted by the input device to limits between the error classes. Thus, the curve RG ₀ finally results in the used cleaning limit RG +, which has a stepped course. An assignment of the curve RG ₀ to the cleaning limit RG + takes place in each case for each matrix element, wherein the portion of the cleaning boundary RG + runs below the respective class, if the curve RG ₀ within this class cuts below less than half of the surface of the class.

Figure 5 shows another example of setting a cleaning limit on a yarn cleaner which examines optical color defects of the yarn produced. In this yarn cleaner, for example, foreign fibers of a different color are recognized and removed by the yarn cleaning. The yarn is scanned by a wavelength-sensitive sensor and in the diagram the wavelength is plotted over the error length L. In the example of FIG. 5, the yarn produced is intended to comply with two wavelength bands λ _A and λ _B of tolerable yarn error. For the upper wavelength band λ _A , the upper cleaning limit RG _{A +} and the lower cleaning limit RG _{A- are set} by the corresponding set points P for this purpose. For example, in Fig. 5, the set point P _{A +} for setting the upper cleaning limit RG _{A + is} shown. For the lower, tolerable wavelength band λ _B , the upper cleaning limit RG _{B +} and the lower cleaning limit RG _{B- are} specified. Any color length errors outside of these two wavelength band ranges are detected by the electronic yarn cleaner and separated from the running yarn as needed.

In one embodiment, the setting routine for setting a color aberration according to FIG. 5 is also implemented on a setting unit for setting the cleaning limits according to FIG. 1 (thickness error). The parameters are transmitted to the electronic yarn cleaner, which detects both types of defects (color and thickness errors) and provides corresponding error signals. The data evaluation can be z. B. done with a fast digital signal processor. Only in the optical signal acquisition different optoeletronic components are required to register the thread diameter on the one hand and on the other hand, the color of the thread.

FIG. 6A shows a yarn cleaner system consisting of the machine center or yarn cleaner control unit 10 for setting the cleaner limit and a yarn cleaner base system 20. The setting of the cleaner limit according to the method described above takes place in a first embodiment in the machine center 10 of the spinning machine, which also controls the processes of the spinning machine and controlled. Or the adjustment takes place in a second embodiment in a Garnreinigerzentraleinheit 10, which is independent of the machine center of the spinning machine for setting Gamreinigem 22, their control and evaluation. In this case, then stands the Garnreinigerzentraleinheit 10 with a machine center of Spinning machine in conjunction to exchange control commands or other data.

The CPU 10 includes a CPU as a curve and parameter generator. The CPU is connected to a display device or a display 12, on which the parameter curves are displayed in graphical form. Furthermore, the CPU 11 is connected to an input device 14, for example an alphanumeric keyboard, or the input device 14 is integrated as a so-called touch screen on the display 12. The input device 14 is used to select the basic form of the cleaner boundaries RG _0-3 or predefined by the customer form RG _C, setting the Aufpunktes P in the coordinate system for the yarn errors and the adaptation of the selected curve (scaling factors as described above, so that modified curves RG _{x, y, φ} arise). The CPU 11 fetches from a memory 15 the predetermined basic forms of the cleaning limit RG _0-3 or already pre-edited form RG _{c, mod} and stores there the edited curves for intermediate storage. Furthermore, 15 parameter data are temporarily stored in the memory 15, which are temporarily stored due to the already edited cleaner limit to be set in the yarn cleaners 22. After the user of the yarn cleaner system has determined the final edited cleaner curve and determines it for (later) adjustment to the yarn cleaners, the parameter data is generated by the CPU 11, for example by transformation of the specified cleaner curve. In the transformation, the specified cleaner curve is scanned by means of a predetermined screening and "nearest" pairs of values determined, see, for example, the "actual" from these pairs of values, used by Garnreiniger cleaner curve RG + and Figure 4. The value pairs are cached in the memory 15 and then at the setting of the yarn cleaner retrieved from the memory 15 and transmitted by a communication device 13 via the communication path of the base systems 20, 30 to the yarn cleaner 22. Accordingly, this also applies to Figure 6B.

In the example of FIG. 6A, the parameters of the finally-edited cleaning curve for adjusting the yarn cleaner 22 are transmitted via a yarn-cleaner-own communication system. This has a cleaner bus 21, with which the yarn cleaner 22 are each connected individually via a data interface. The Gamreiniger setting is preferably carried out before the start-up of the spinning machine or before production of a new batch, but can also be done during the spinning operation, so that there is a change in the cleaning limit during production. Continuously measured data and status parameters are in turn transmitted from the yarn cleaners 22 via the cleaner bus 21 to the yarn cleaner central unit 10.

FIG. 6B shows a second embodiment of the yarn cleaner system, in which the communication structure is integrated into that of the spinning machine. The parameters for programming the cleaner curve in the yarn cleaners 22 are here also transferred to a machine bus 31, transmitted by this to section controllers 32, which in turn transmit the parameters via a section bus 33 to the yarn cleaners 22 transmitted. At each section controller 32 each more spinning units of the spinning machine are connected, which are controlled and monitored by the section controller. Instead of the section bus 33, the yarn cleaners 22 may also be connected directly to the section controller 32. In Figs. 6A and 6B, the number of yarn cleaners 22 and the number of section controllers 32 are given by way of example only, it being understood that their numbers may be substantially higher.

Claims (18)

1. A method for adjusting a clearing limit for at least one electronic yarn clearer, where the possible yarn faults are represented in a sorting grade ordered by fault value (φ,λ) and fault length (L) and where the clearing limit (RG) is selected by a curve and cleared by the yarn clearer, wherein the curve predetermining the clearing limit (RG) is set through precisely one point (P) in the sorting grade, where the curve progression of the curve is inherently optional but defined.
2. A method as in claim 1, wherein the curve can be selected from predetermined available sets of characteristic curves (RG₀ - RG₃, RG_C, RG_A+, RG_A-, RG_B+, RG_B-) with curve progression of different shapes.
3. A method as in claim 1 or 2, wherein the curve (RG) is scaleable.
4. A method as in claim 3, wherein the curve (RG) relating against fault value (φ, λ) and/or fault length (L) is scaleable.
5. A method as in claim 3 or 4, wherein the scale factor is a compressing- and/or expanding factor.
6. A method as in claim 3, 4 or 5, wherein the scale factor is an angle (ϕ).
7. A method as in one of the previous claims, wherein the sorting grade is represented in a table and/or coordinate system.
8. A method as in one of the previous claims, wherein the fault value represents a fault cross section (φ), a fault property, hairiness or a colour deviation.
9. A method as in one of the previous claims, wherein at least two clearing limits (RG_A+, RG_A-, RG_B+, RG_B-) are defined adjustable to the upper and lower limit of at least one clearing range (λ_A, λ_B).
10. A method as in one of the previous claims, wherein at least on curve (RG_C) represents a definable or alterable curve.
11. An adjusting device to select and define a clearing limit (RG) for electronic yarn clearers (22) comprising a processor (11), a communications system (13) for transferring the setting parameters to the electronic yarn clearers (22), a display (12) and an input device (14) for feeding the setting parameters into the processor (11), wherein at least two basic types of inherently optional but defined cleaning limits (RG _{0-3, C, A+, A-, B+, B-}) are stored in a memory location (15), whereat by the processor and the feeded edit parameters (P, x, y , ϕ) a modified cleaning limit (RG_X,Y,ϕ) is generateable for display and by the processor (11) a set of setting parameters for the transfer to the electric yarn clearers (22) is generateable from a selected modified cleaning limit.
12. An adjusting device as in claim 11, wherein the memory location (15) comprises at least one already modified cleaning limit (RG _{X, Y,ϕ}) storable as a predetermined cleaning limit.
13. An adjusting device as in claim 11 or 12, wherein the adjusting device is part of a central control unit machine (10) of a spinning machine.
14. An adjusting device as in claim 11, 12 or 13, wherein the display (12) provides the defined and/or modified cleaning limit (RG_0-3, _C, RG_X,Y,ϕ) in a graphical view (Fig. 1-5) preferably in form of a coordinate system.
15. Yarn clearer system with an adjusting device (10) as in one of the claims 11 to 14, a plurality of electronic yarn cleaners (22) and a communications system (21; 31, 32, 33) for transferring the set of setting parameters to the electronic yarn clearers (22).
16. Yarn clearer system as in claim 15, wherein the communication system comprises a control bus (31) of a spinning machine.
17. Yarn clearer system as in claim 16, wherein the communication system comprises a plurality of section controllers (32).
18. Yarn clearer system as in claim 17, the communications system comprises a plurality of section busses (33).

Images