WO2024251596A1 - Method for verifying the validity of a display value during a combing process and combing machine - Google Patents

Abstract

The present invention relates a method for verifying the validity of a display value during a combing process in which a combing machine (1; 100) produces a combed sliver (3) from a material supply (4), wherein the combing machine (1; 100) has a number of combing heads (2), which each have a gripper apparatus (14), through which a lap (6) of the material supply (4) presented to the combing head (2) can be guided, a circular comb (21) for combing out noir (24) from fibre tufts of the lap (6) securely clamped by the gripper apparatus (14), and a bonding device (28) for forming an individual combing-head sliver (29) from the combed-out fibre tufts; a suction-extraction device (26) for extracting the noir (24); a compacting device (37) for bringing together the individual combing-head slivers (29) to form the combed sliver (3); an evaluation unit (56); a display device (57), coupled to the evaluation unit (56); and a detection device (55), coupled to the evaluation unit, for detecting an actual progression (74) of at least one detection variable that varies over time and can be assigned to the combed sliver (3) and/or at least one of the individual combing-head slivers (29), and wherein the method comprises the following steps, which are carried out during the process of combing the material supply (4): displaying the display value on the display device, wherein the display value reproduces a noir fraction assigned to a reference progression (64) stored in the evaluation unit; comparing the actual progression (74) of the at least one detection variable with the reference progression (64) by means of the evaluation unit; and, if the comparison shows that the actual progression of the at least one detection variable lies outside a predetermined tolerance zone (75) of the assigned reference progression (64), at least for a time, generating a warning signal (77) that the display value is invalid.

Description

Title: Method for checking the validity of a display value during a combing process and combing machine

Description

The present invention relates to a method for checking the validity of a display value during a combing process in which a combing machine produces a combing band from a wadding template, the combing machine having a plurality of combing heads, each of which has a pair of pliers through which a wadding band of the wadding template presented to the combing head can be guided, a circular comb for combing out combing noils from fiber tufts of the wadding band clamped by the pair of pliers, and a consolidation device for forming an individual combing head band from the combed out fiber tufts, a suction device for suctioning the combing noils, a compression device for combining the individual combing head bands to form the combing band, an evaluation unit, a display device coupled to the evaluation unit, and a detection device coupled to the evaluation unit for detecting an actual course of at least one time-varying value attributable to the combing band and/or at least one of the individual combing head bands. detection size.

The yarn quality is determined, among other things, by the proportion of long fibers in the yarn. In order to influence this, combing machines are used in the spinning preparation phase, which comb out a certain proportion of short fibers, neps, trash and dust from the feed wadding. For this purpose, wadding bands from wadding feeds, which can include wadding rolls or band feeds from fiber band cans, are fed to the individual combing heads of the combing machine. When the wadding bands are combed out by the circular combs of the individual combing heads, the waste that is produced is called combing noil and is sucked away by the combing heads using the suction device.

The current noil proportion can be determined based on the amount of noil that is sucked out. To do this, in a process step that is usually carried out manually, the noil waste is intercepted within a certain period of time at a central suction device connected to the combing machine or directly at the combing machine using a slide that is inserted into a central suction channel of the suction device. The combing sliver produced by the combing machine during this period of time is also cut off. The combing degree of the combing machine can be determined by subsequently weighing the cut-off combing sliver and the intercepted noil separately. If K is the weight of the intercepted noil and G is the weight of the cut-off combing sliver and the intercepted noil, then p = 100% of the noil proportion. The noil proportion represents the percentage of the weight of the feed wadding and the weight of the combing noil. After the noil proportion has been determined, the combing process continues as usual, with the combing sliver being produced from the cotton slivers of the material template. However, since the determination is time-consuming and associated with costs for the spinning mill, the noil proportion is often only checked sporadically. However, deviations from the last determined noil proportion can remain undetected for a longer period of time. The result is, for example, an excessively high noil proportion, which would result in a poor utilization rate of the material template provided. Causes for this, such as a change in the template quality, wear on components of the combing heads and the like, are therefore not recognized and cannot be remedied. Closer monitoring of the noil proportion could optimize the utilization rate and reduce unwanted waste, but is too complex due to the manual effort involved.

WO 93/12278 A1 discloses an arrangement of sensors for automatically detecting the combed noils. DE 102006002390 A1 describes the associated setting options of the combing machine depending on the fiber quality.

In DE 102007039067 A1, each combing head of a combing machine has sensors that measure the weight of the lap in front of the combing head. The combed-out comb noils are removed via a suction device under the circular comb. After the combing head, the output mass is measured using a measuring funnel or sensor and compared with the input mass. An evaluation unit compares the measurement data, whereby the difference should correspond to the mass of the combed-out comb noils. The comb noil proportion is shown on a display device.

The disadvantage of automatic noil detection is that its implementation in the combing machine is associated with high costs.

The object of the present invention is to provide a cost-effective and easy-to-implement method for displaying the current noil proportion on the combing machine.

The object is achieved by the method of the type mentioned at the outset in that the combing machine has an evaluation unit, a display device coupled to the evaluation unit and a detection device coupled to the evaluation unit for detecting an actual course of at least one time-varying detection variable assignable to the combing band and/or at least one of the individual combing head bands, and in that the method comprises the following steps which are carried out during the combing process of the material feed: displaying the display value on the display device, wherein the display value represents a combing noil proportion which corresponds to a value stored in the evaluation unit. reference curve is assigned; comparing the actual curve of the at least one recorded variable with the reference curve by means of the evaluation unit; and if the comparison shows that the actual curve of the at least one recorded variable is at least temporarily outside a predetermined tolerance field of the assigned reference curve, generating a signal that the noil portion is invalid.

For the sake of better readability, "the at least one time-varying detection variable that can be assigned to the combing belt and/or at least one of the individual combing head belts" is referred to as "the detection variable", whereby this still means exactly one detection variable or several of the detection variables. If the exact number is important, this will be indicated at the appropriate point. It therefore goes without saying that the detection device can only detect exactly one detection variable or several of the detection variables.

It was found that the detection value in the combing operation of the combing machine always follows a constant course over time, as long as no boundary conditions influencing the sliver quality of the combing sliver change during the combing operation. The boundary conditions can relate to delivery speed, number of combing cycles, quality of the lap slivers and/or a changed material composition or mixing ratio, provision of laps from another lap winder, defective or worn components of the combing machine, blockages on the combing head, etc. If the detection value deviates from the usual course, this is an indication that the combing noil proportion has changed. The operator can therefore assume that the combing noil proportion shown on the display device is valid until the actual course of the detection value deviates from the reference course. This simplifies and optimizes the operation of the combing machine. It is therefore sufficient to monitor the actual course of the detection value in order to be able to make a statement about the validity of the display value, i.e. the correctness of the displayed noil proportion, by comparing it with the reference course. If the display value is valid, the actual course of the detection value follows the reference course over the time of the combing process and the noil proportion shown on the display device corresponds to the current noil proportion that is currently occurring during operation of the combing machine. If, on the other hand, the display value is invalid, the actual course of the detection value deviates from the reference course and the current noil proportion deviates from the noil proportion shown on the display device. The operator can then be instructed to take further steps in an event-controlled manner. Automating the event-controlled noil determination is also possible with the appropriate implementation of automatic noil detection. For example, the temporary introduction of a receiving device for picking up and/or collecting the Combing noils in the suction device can be automated, and the collecting means can also be designed sensor-based, for example by means of optical or inductive sensors in the suction tract.

To ensure that the reporting signal is not generated even in the case of a slight deviation, deviations of the actual course of the recorded value from the reference course are tolerated up to a certain extent. For this purpose, the tolerance field of the reference course is stored in the evaluation device. The size of the tolerance field can be specified by the operator of the combing machine. Only when the reporting signal is generated is the operator made aware of the event that the displayed noil proportion is no longer valid.

Overall, there are several advantages, so that raw material savings can be achieved through optimally set waste quantities. Influences such as supply fluctuations, raw material changes or due to changed combing machine settings are detected early. Incorrect settings of the combing machine can also be detected and rectified. Defective components of the combing machine, e.g. circular comb clothing, can also be detected and replaced before the combing machine fails. Not only can the combing process be analyzed completely, but the combing noil proportion can also be documented over the operating life of the combing machine, since appropriate data recording, in particular statistical evaluation, is possible, for example, as part of a quality management system, which can also be carried out with the evaluation unit. Another advantage is that, by additionally taking laboratory data into account, a connection can be derived between supply, combing sliver and combing noil data and, for example, the combing noil proportion recorded online and the combing noil quality. In this way, permanent noil determination can be achieved with only minimal manual effort, since recalibration is only necessary when triggered by an event, namely when the display value is invalid.

Furthermore, the actual curve can reflect the curve of the detection variable over time. The actual curve of the detection variable can be compared with the reference curve during the combing process continuously or discontinuously or at discrete times, for example at intervals of 1 second, 5 seconds, 1 minute. The reference curve can depict a temporal curve of the detection variable that the detection variable follows over time under constant boundary conditions of the combing machine during the combing process.

When monitoring the capture size in the combing process, special situations may have to be taken into account that cause a change in the delivery speed of the combing machine, for example a can change, a machine stop and the like. Special situations can lead to temporary deviations of the actual curve from the reference curve, which preferably do not lead to the generation of the report signal. For example, an observation window can be specified in the combing process, so that the comparison of the actual curve with the reference curve only starts at the beginning of the observation window and stops at the end of the observation window. The observation window can have a starting point, which can be defined, for example, by specifying that a minimum sliver length of just three meters, for example, must be combed, that the delivery speed set for the combing process must be reached, that a minimum time must have elapsed, etc. An end point for the observation window can also be defined in a similar way. This means that when the can is changed, for which the delivery speed of the combing machine is reduced, the observation window can close and only open again when the set delivery speed is reached.

In a further development, the alarm signal can only be generated if the comparison shows that the actual course of at least one recorded variable lies outside a specified tolerance field of the assigned reference course for longer than a specified period of time. The period of time can be, for example, 1 second to 10 minutes. The extent to which the actual course deviates from the reference course can be taken into account. If the evaluation unit recognizes that the actual course and the reference course are deviating more and more from one another, it can be provided that if a predeterminable threshold value, which can lie outside the tolerance field, is exceeded, the alarm signal is generated before the end of the specified period of time.

The material feed can be a winding feed or a ribbon feed from sliver cans in a conventional manner. The procedure for loading the combing machine with winding or ribbon feed is usually specified in a spinning mill in order to take spinning mill-specific conditions into account. For example, the material feed on all combing heads can be completely changed and the combing process is only normally completed when the next change is due, when all combing heads are again loaded. Alternatively, the combing heads can also be loaded in blocks, so that, for example, in a 12-head combing machine, the first six combing heads are changed at the beginning of the combing process and the second six combing heads are changed halfway through the combing process.

Furthermore, it can be provided that after the material template has been combed out, the combing process is repeated with new material templates until the report signal is generated. The advantage is that as long as the display value is valid, the displayed noil proportion corresponds at least substantially to the actual noil proportion, i.e. within the specified tolerances, and thus the combing process does not have to be interrupted to determine the noil.

If the signal is generated, the evaluation unit can provide information, for example that the combing process, i.e. the production of the combing machine, must be stopped, the noil proportion must be recalculated, the reference curve must be re-recorded, the combing machine must be cleaned, the combing heads must be checked for possible blockages, possible repairs must be carried out, etc.

After the signal has been generated, a current noil proportion can be determined based on the amount of noil sucked out by the suction device and reassigned to the reference curve stored in the evaluation unit. This can be particularly advantageous if a defective component has been repaired or replaced, or a blockage on a combing head has been cleared, or something similar. This means that the noil proportion stored in the evaluation unit can be replaced by the newly determined noil proportion. In principle, however, it can also be provided that the signal is acknowledged manually in order to declare the display value as valid again. This can be particularly useful after repairing or replacing a defective component, clearing a blockage on the combing head, or something similar, since the combing process can and will then continue with the same boundary conditions. From the time at which the current noil proportion has been reassigned to the reference curve or the reporting signal has been acknowledged, the evaluation unit recognizes the noil proportion shown on the display device as valid again until the comparison of the actual curve of the recorded variable with the reference curve again detects a deviation and the evaluation unit generates the reporting signal. The current noil proportion is determined in a conventional manner, either manually or automatically.

The reference curve is preferably created based on a reference run. The current boundary conditions on the combing machine can be taken into account in the reference run. It is advantageous if the reference run comes as close as possible to the combing process or corresponds to it in terms of the boundary conditions that influence the sliver quality of the combing sliver. In particular, the current combing noil proportion is determined during the reference run. This ensures that the combing noil proportion reproduced in the subsequent combing process indicates the last determined combing noil proportion, i.e. the current combing noil proportion. The reference run is preferably carried out on the combing machine on which the combing process is also carried out, in which the combing machine produces a combing sliver from the material template. Alternatively, it can also be provided that a database with reference curves is stored in the evaluation unit so that the operator can select one of the stored reference curves for the material template presented. Furthermore, it can be provided that the combing machine combs out a reference template with a reference wadding band for each combing head during the reference run. The reference template does not differ from the material template in a practical way. It is also advantageous if the procedure for changing the reference template during the reference run corresponds to the procedure during the combing process, for example complete or block-wise change. The reference curve thus reflects the expected actual curve of the recorded variable in the combing process, provided that the combing noil proportion remains constant during the combing process. Otherwise, the comparison shows that the display value is invalid, whereupon the current combing noil proportion can be re-determined. Preferably, the display value is no longer displayed until the new combing noil proportion has been determined in order to avoid the operator assuming an incorrect combing noil proportion.

The cotton ribbon quality of the reference cotton ribbons expediently corresponds to the cotton ribbon quality of the material template to be combed after the reference run. It is also advantageous if the ribbon lengths of the reference cotton ribbons of the reference template presented in the reference run correspond at least as far as possible to the ribbon lengths of the cotton ribbons of the material template presented in the combing process. In particular, the respective reference cotton ribbon can have a ribbon length of more than 80 meters and/or less than 1000 meters and more preferably at least 100 meters and a maximum of 700 meters. For example, the reference run can extend over a period of at least 30 minutes and/or a maximum of 390 minutes. Expediently, the reference template is also based on the combing process and the material template intended for the combing process in terms of ribbon length and/or duration, which is determined in particular by specifying the feed amount and the number of combing cycles.

In particular, the reference run is carried out before the combing process and/or after the signal has been generated and/or when a boundary condition affecting the combing band changes. This ensures that the displayed noil proportion always corresponds to the current noil proportion and in particular only needs to be determined if the display value is declared invalid due to a deviation of the actual course of the recorded variable from the reference course.

The evaluation unit can create the reference curve from the actual curve of at least one recorded variable recorded during the reference run. The reference curve can represent the curve of the reference variable changing over time. The reference curve can represent this in the form of a curve over time. If several of the recorded variables are recorded, the reference curve can have its own curve for each of the recorded variables. The actual curve of the respective recorded variable can thus be compared with the associated curve of the reference curve. The detection device can comprise at least one sensor and preferably one sensor for each detection variable. The detection variable can comprise a sensor output signal from a respective sensor, which can be detected continuously or discontinuously. In this way, the respective sensor output signal can be used to create the reference curve using the sensor output signals detected in the reference run, and to compare the actual curve of the sensor output signal with the reference curve in the combing process.

According to a first embodiment of the detection device, it can comprise a sensor assigned to the combing belt for detecting the at least one detection variable. This sensor can be designed, for example, as a distance sensor, displacement sensor or the like. For example, the sensor can be arranged on a first roller of a pair of sensing rollers through which the combing belt passes. The first roller can in particular be spring-loaded and held so as to be movable relative to a second roller of the pair of rollers. The passing combing belt can be further compressed between the pair of sensing rollers. The sensor assigned to the combing belt can also be a tactile, inductive, optical sensor. The sensor output signal can be proportional to a belt mass of the outgoing combing belt. However, it is advantageous that the evaluation unit does not have to be calibrated, since the comparison can be carried out using the directly detected sensor output signal. It is therefore sufficient to monitor the actual course of the sensor output signal and compare it with the reference course. However, an actual curve of a processed value derived from the sensor output signal, such as the strip mass, strip thickness, etc., can also be used for comparison with the reference curve. The sensor output signal viewed over time follows the reference curve in the combing process, even with each additional material feed, provided the boundary conditions in the combing process remain constant or the combing noil proportion does not change. The sensor assigned to the combing strip can therefore supply the sensor output signal, the actual curve of which is monitored during the combing process and/or which is recorded in the reference run in order to create the reference curve from it. The sensor assigned to the combing strip can be arranged in the area of or on or in the strip running direction of the combing strip behind the compacting device and in particular at the strip outlet of the combing machine. The compacting device is, for example, a funnel, a fleece nozzle or the like in which the combing strip is formed. Another advantage is that the method can be implemented in a simple manner, since a standard combing machine usually has such a detection device with a sensor assigned to the combing belt, which in a specific embodiment can be a disk monitoring device. According to a second embodiment of the detection device, which can be provided alternatively or in addition to the first embodiment of the detection device, this can have a sensor assigned to the respective individual head combing band for each combing head for detecting the detection variable of the respective individual head combing band. The statements with regard to the first embodiment of the detection device can also apply analogously to the second embodiment of the detection device, since the principle of the second embodiment differs in that a sensor assigned to the individual head combing band is provided on each combing head. The respective sensor can correspond in structure and function to the sensor assigned to the combing band. The sensor output signals of the sensors can be detected in the reference run, whereby the reference curve can have its own curve for each sensor or for each of the detection variables. The actual curve of the respective detection variable can thus be compared with the associated curve of the reference curve. The sensors assigned to the individual combing head bands can be arranged on or behind the respective consolidation device of the respective combing head in the direction of belt travel. For example, the respective sensor can be arranged on a first roller of a pair of rollers, which is held movably relative to a second roller of the pair of rollers, in particular spring-loaded. The respective pair of rollers can, for example, be a pair of calender rollers equipped with the sensor, for example a distance sensor, which can be part of the consolidation device.

For all embodiments, it can also apply that the combing machine can have a drafting system for refining the single-head comb bands. The drafting system can be arranged in the direction of travel of the band between the consolidation devices of the combing heads and the compacting device. The combing machine can comprise just one drafting system through which all of the single-head bands are guided, or several, for example two, of the drafting systems, through which a subset of the single-head bands are guided. The drafting system can have a main drafting field and optionally at least one pre-drafting field. For example, the drafting system can be designed as a three-over-three, four-over-three, four-over-four or five-over-four drafting system.

In particular, the drafting system can have an input roller that can be driven by a first drive and an output roller that can be driven by a second drive, so that the input roller and the output roller can be driven separately from one another. It is fundamentally possible for the drafting system to have at least one non-driven roller in front of the input roller and/or between the input roller and the output roller and/or behind the output roller in the direction of the belt. The detection device can thus detect the peripheral speeds or rotational speeds of the input and output rollers. According to a third embodiment of the detection device, which can be provided alternatively or in addition to the first and/or second embodiment of the detection device, this can detect a draft ratio of the drafting system as the at least one detection variable. The draft ratio can thus be used to check when the current noil proportion in the combing process deviates from the noil proportion shown on the display unit. If the actual course of the draft ratio in the combing process follows the reference course, the boundary conditions have not changed or the displayed noil proportion continues to correspond to the current noil proportion. The ratio of peripheral speeds of roller pairs of the drafting system working one after the other can reflect the draft ratio.

If the detection variable includes the draft ratio, the sensor output signal of the sensor assigned to the combing sliver can be used as a further detection variable. Its sensor output signals, which can be proportional to the sliver mass of the outgoing combing sliver, will be largely constant over the time of the combing process due to the draft adjustment in the drafting system. The reference curve can therefore have two curves, a first for the draft ratio and a second for the sensor output signal of the sensor assigned to the combing sliver. If the sensor output signals of the sensor assigned to the combing sliver deviate from the associated curve during the combing process, which in particular has a constant value over time, this is also an indication that the boundary conditions have changed or that the reproduced combing noil proportion can no longer correspond to the current combing noil proportion, so that the report signal can then also be generated.

If the drafting system is regulated, or the draft adjustment can be changed by changing the peripheral speeds of the input and/or output rollers, the sensor output signal of the sensor assigned to the combed sliver can be fed to the evaluation unit in order to be able to regulate, for example, long-wave periodic fluctuations in the individual head combed slivers presented to the drafting system. The drafting system can thus carry out a draft adjustment in order to achieve a uniform sliver mass for the combed sliver.

According to a fourth embodiment of the detection device, which is a further development of the first and/or second embodiment and can be provided alternatively or in addition to the third embodiment, the draft adjustment is recorded in the reference run and stored as a draft curve in the evaluation unit, wherein during the combing process the drafting system adjusts the draft according to the draft curve. The draft adjustment can be carried out over time by adjusting the ratio of the peripheral speeds of the successively operating roller pairs of the drafting system. The detection device can comprise the sensor assigned to the combing band and/or the sensors assigned to the individual combing head bands. The detection variable of the respective sensor can be its sensor output signal, which over time, i.e. its actual course, follows the reference course. If a deviation is detected in the comparison, the corresponding report signal is generated. Due to the draft adjustment, by means of which long-wave periodic fluctuations of the individual head combing bands presented to the drafting system are to be compensated, the actual course of the sensor output signal assigned to the combing band will correspond to a largely constant value. The respective sensor output signals can be recorded in the reference run and the reference course can be created based on this, which can have its own course curve for each of the detection variables if there are several sensors. During the combing process, the actual course of the detection variable assigned to the combing band can be used for the comparison.

The method can therefore be designed to be particularly simple in terms of the detection device or can use sensors that are already installed as standard in a conventional combing machine. The advantage is that complex measurement methods such as weighing the incoming mass of the cotton strips, for example by weighing the individual cotton rolls, are not necessary with the method. As long as the actual course of the detection value follows the reference course, the boundary conditions are unchanged or the reproduced noil proportion continues to correspond to the current noil proportion of the combing machine.

A further solution to the above-mentioned problem consists in a combing machine of the type mentioned at the outset, which is designed to produce a combing band from a material template, wherein the combing machine has a plurality of combing heads, each of which has a pliers device through which a cotton band of the material template presented to the combing head can be guided, a circular comb for combing out comb noils from fiber tufts of the cotton band clamped by the pliers device and a consolidation device for forming an individual combing head band from the combed out fiber tufts; a suction device for suctioning the comb noils; a compression device for combining the individual combing head bands to form the combing band; an evaluation unit; a display device coupled to the evaluation unit; and a detection device coupled to the evaluation unit for detecting an actual course of at least one time-varying detection variable assignable to the combing band and/or at least one of the individual combing head bands. The combing machine is configured to carry out the method described above. The combing machine according to the invention provides the same advantages as those described in connection with the method according to the invention, so that reference is made here for short to the above description. It goes without saying that all the above-mentioned embodiments of the method can be transferred to the combing machine and vice versa.

Further features and advantages of the invention will become apparent from the following description of preferred embodiments. Features that are essentially or functionally the same or similar are provided with the same reference numerals. They show:

Figure 1 is a representation of a combing machine according to the invention which produces a combing ribbon from cotton ribbons of a winding template;

Figure 2 is a schematic representation of a combing head of the combing machine of Figure 1;

Figure 3 is a schematic representation of a drafting system of the combing machine from Figure 1;

Figure 4 is a flow chart of a reference run of a method according to a first embodiment of the invention, wherein during the reference run, sensor output signals of a sensor of the combing machine from Figure 1 assigned to the combing band are detected as detection variables;

Figure 5 shows a reference curve created on the basis of the reference run from Figure 4;

Figure 6 is a flow chart of a combing process of the method using the combing machine of Figure 1;

Figure 7 shows a method step carried out during the combing process in which an actual curve of the input variable is compared with the reference curve from Figure 5;

Figure 8 shows the method step from Figure 7, whereby the comparison shows that the actual course of the detection variable lies outside a predetermined tolerance field of the reference course;

Figure 9 shows a reference curve created on the basis of a reference run of a method according to a second embodiment of the invention, wherein during the reference run sensor output signals from sensors of the combing machine from Figure 1 assigned to individual combing head bands are recorded as the detection variable;

Figure 10 shows a method step carried out during the combing process in which an actual curve of the input variables is compared with the reference curve from Figure 9;

Figure 11 shows a reference curve created on the basis of a reference run of a method according to a third embodiment of the invention, wherein during the reference run, a draft ratio of a drafting system of the combing machine from Figure 1 is recorded as the recording variable;

Figure 12 shows a method step carried out during the combing process in which an actual curve of the input variable is compared with the reference curve from Figure 11;

Figure 13 shows a draft adjustment of a drafting system of the combing machine from Figure 1 recorded during a reference run of a method according to a fourth embodiment of the invention;

Figure 14 shows a reference curve created on the basis of the reference run from Figure 13, wherein during the reference run sensor output signals of a sensor assigned to the combing band of the combing machine from Figure 1 are recorded as the recording variable;

Figure 15 shows a process step carried out during the combing process, in which an actual curve of the input variable is compared with the reference curve from Figure 14, whereby during the combing process the drafting system adjusts the draft according to the draft curve from Figure 13; and

Figure 16 is a representation of another combing machine according to the invention, which produces a combing sliver from cotton slivers of a sliver template made of sliver cans.

Figure 1 shows a combing machine 1 with, here as an example, eight combing heads 2, which is designed in a manner known per se to produce a combing band 3 from a material template 4. The combing machine 1 can also comprise fewer or more than the eight combing heads 2, for example twelve or 16 combing heads. Figure 2 shows one of the identically constructed combing heads 2 in detail. The combing machine 1 is described in more detail below with reference to Figures 1 and 2.

The material template 4 is, here, a winding template, so that each combing head 2 is provided with its own cotton roll 5 with, for example, 80 ktex fibers, which can have a width of, for example, approximately 300 millimeters. Each cotton roll 5 has a cotton tape 6 that is wound on a winding tube 7. The length of the respective cotton tape 6 is usually between 300 meters and 500 meters, but can in principle be between 80 meters and 1000 meters.

The respective combing head 2 can comprise two winding rollers 8, 9, of which the front winding roller 8 can be driven. The respective lap roll 5 lies on the winding rollers 8, 9. The lap band 6 can be deflected on a deflection roller 12 and is transferred to a feed cylinder 13 of a nipper device 14. On the deflection roller 12, which here is a gear (not shown), a pressure roller 17 can be arranged which is pivotably mounted and loaded about a lever 15 via a spring 16. This embodiment with the deflection roller 12, the lever 15 loaded with the spring 16 and the pressure roller 17 is preferably only used in an automatic lap application process and does not have to be part of the combing machine 1.

The pliers device 14 can be moved back and forth via levers 18, 19 and driven via a shaft 20, which can be connected to the gear (not shown). A ratchet wheel (not shown) is attached to the feed cylinder 13, which is gradually rotated by a ratchet (not shown) as the pliers device 14 moves back and forth, thereby feeding the cotton strip 6 to the jaws of the pliers device 14 with a feed amount that can be adjusted in particular for combing. In a manner known per se, the cotton strip 6 that is fed in at each combing head 2 is gradually unwound from the cotton roll 5 during operation of the combing machine 1, and fibers are torn out and combed out. A circular comb 21 is rotatably mounted beneath the pliers device 14, which combs out the fiber tuft fed in by the closed pliers device 14 via its comb segment 22. The circular comb 21 can also be connected to the drive of the gear (not shown). Together with a top comb 23, short fibers, neps and impurities are removed from the fiber material, which are sucked as so-called combing noils 24 through a guide shaft 25 of a suction device 26 into a central suction channel 27, which is assigned to all comb heads 2 of the combing machine 1.

The nipper apparatus 14 is followed by a consolidation device 28 for forming a single combing head band 29 from the combed fiber tufts. According to the example shown in Figure 2, the nipper apparatus 14 is in a front position and transfers the combed fiber tuft to a subsequent tear-off roller pair 30. The combed single combing head band 29 then runs through another tear-off roller pair 31, a take-off roller pair 10, also called a delivery roller pair, and a calender roller pair 11 with a first calender roller 32 and a second calender roller 33, which are held so that they can move relative to one another. A band forming funnel 67 can be arranged above the calender roller pair 11, for example. One of the two calender rollers 32, 33 can be spring-loaded and pivotably mounted and the other can be mounted in a fixed position. The calender rolls 32, 33 serve to further consolidate the single comb head belt 29.

By detecting the distance between the two calender rollers 32, 33 or the size of the change in distance, the individual combing head belt 29 can be monitored if necessary. For this purpose, a sensor 34 associated with the individual combing head belt 29 can be provided, which can be designed, for example, as a path or distance sensor, although other suitable sensor types are possible in order to be able to monitor, for example, the strip mass or thickness progression.

The individual combing head band 29 guided through the pair of calender rollers 32, 33 is delivered to a deposit table 35 which is assigned to all combing heads 2 of the combing machine 1. On the deposit table 35, the individual combing head bands 29, in particular arranged next to one another, are guided to a common drafting system 36. The eight individual combing head bands 29, here, run into the drafting system 36, are stretched and doubled, for example by a factor of 18, and combined to form the combing band 3 by means of a compression device 37, which can comprise a band funnel, for example. The combing band 3 can then be deposited in a can by means of a can deposit 38 at a delivery speed of, for example, approximately 230 meters per minute. It goes without saying that higher or lower delivery speeds, other factors for the draft, other widths for the batting rolls 5, other fiber finenesses for the batting bands 6, etc. are possible than the values mentioned here merely as examples.

The drafting system 36 is shown in more detail in Figure 3. It is, here, a 2-zone drafting system or a 4-over-3 drafting system. It has three pairs of rollers 39, 40, 41, between which the drafting of the fiber composite from the individual combing head bands 29 takes place, namely in the direction of belt travel 59 an input roller pair 39, a middle roller pair 40 and an output roller pair 41. The roller pairs 39, 40, 41 each have a lower roller 42, 43, 44 and an upper roller 45, 46, 47, with a further upper roller 48 being arranged on the lower roller 44 of the output roller pair 41, which deflects the drawn fiber composite. In principle, it could also be a different drafting system, for example a 5-over-4 drafting system. The input roller pair 39 and the middle roller pair 40 form a pre-drafting field 49. A subsequent main drafting field 50 is formed by the middle roller pair 40 and the output roller pair 41. The bottom rollers 42, 43, 44 are rotatably mounted on a machine frame 51 of the combing machine 1.

The drafting system 36 can be an uncontrolled or a controlled drafting system. In order to be able to control the draft ratio, the lower roller 44 of the output roller pair 41 can be driven by a first drive (not shown), the main motor, and determines the delivery speed of the combing machine 1. The lower rollers 42, 43 of the input and middle roller pair 39, 40 can be driven by a second drive (not shown), the control motor. Other drive concepts are also possible. The upper rollers 45, 46, 47, 48 are pressed against the lower rollers 42, 43, 44 by pressure elements 52 and are thus driven by friction. In order to be able to monitor the combing belt 3, in particular its belt mass or belt mass fluctuations, an optional pair of sensing rollers 53 with a sensor 54 assigned to the combing belt 3 can be arranged at the output of the drafting system 36. For example, one sensing roller can be arranged so that it can pivot and in particular is spring-loaded against the other stationary sensing roller. The sensor 54 assigned to the combing belt 3 can be, for example, a distance or displacement sensor, although other suitable sensor types, such as tactile or optical sensors, are also possible. Alternatively, the sensor 54 assigned to the combing belt 3 can also be a microwave sensor, ultrasonic sensor or the like, which can be configured to monitor the belt mass profile or the thickness profile of the combing belt 3. The combing belt 3 can be monitored by detecting the distance between the two sensing rollers of the pair of rollers 53 or the size of the change in distance.

The combing machine 1 usually has the sensors 34 assigned to the individual combing head bands 29 and/or the sensor 54 assigned to the combing band 3. The sensors 34 and/or the sensor 54 belong to a detection device 55 of the combing machine 1, by means of which band quality characteristics of the individual head combing bands 29 and/or the combing band 3 can be monitored. Furthermore, when the drafting system 36 is designed with adjustable draft, the detection device 55 can be connected to the main motor or the first drive of the drafting system 36 and the control motor or the second drive of the drafting system 36 in order to be able to detect the draft ratio based on the ratio of the peripheral speeds of the successively operating roller pairs 39, 40, 41 of the drafting system 36. By means of the detection device 55, various detection variables, namely the sensor output signals of the respective sensor 34, 54 and/or the draft ratio of the drafting system 36 or the peripheral speeds of the successively operating roller pairs 39, 40, 41 of the drafting system 36, can be detected.

The detection device 55 is coupled to an evaluation unit 56 of the combing machine 1. The evaluation unit 56 can be coupled to a control of the combing machine 1, be part of the control or itself form the control of the combing machine 1. Furthermore, the evaluation unit 56 can be coupled to a display device 57 or a display of the combing machine 1. Furthermore, an input field 58 can also be provided on the display device 57, via which the operator of the combing machine 1 can make inputs.

Figure 4 shows a flow chart of a reference run of a method according to a first embodiment of the invention. The reference run is used only to obtain information and is intended to depict the subsequent combing process, during which the combing machine 1 produces the combing band 3 in the usual way from the material template 4 provided or the material templates 4 that are repeatedly provided. The The basic idea is that information obtained from the reference run should apply to the subsequent combing process(es). This is checked again and again during the combing process. As soon as there is a deviation, the operator of combing machine 1 is informed.

The reference run starts with Start 60, in which the combing machine 1 produces a combing band 3 with the boundary conditions that also apply to the combing process, such as delivery speed, etc., from a reference winding template that corresponds to the properties of the material template 4. The reference winding template has a lap roll 5 with a reference lap band for each combing head 2.

During the reference run, in step 61, the detection device 55 detects the time-varying detection variable that can be assigned to the combing belt 3 and corresponds to the sensor output signal of the sensor 54 assigned to the combing belt 3. The detection device 55 transmits the continuously or discontinuously detected detection variable to the evaluation unit 56.

In step 62, the amount of noil 24 that accrues within a certain period of time and is sucked away by the suction device 26 is measured. To do this, the noil for the certain period of time can be collected in the suction channel 27, removed and then weighed in a manner known per se. Automatic noil determination is also possible. Furthermore, the combing sliver 3 produced by the combing machine 1 in this period of time is cut off. The degree of combing out of the combing machine 1 can be determined in step 63 by subsequently weighing the cut off combing sliver and the collected noil separately. If K is the weight of the intercepted noil and G is the weight of the cut off combing sliver and the intercepted noil, then p = 100% of the noil proportion. The noil proportion represents the percentage of the weight of the feed wadding and the weight of the noil. The noil proportion is set on the combing machine as required and is usually in a range between 5 and 20 percent and generally depends on the desired yarn quality, which is achieved by subsequently spinning out the combing sliver 3.

The current noil proportion can be calculated by the evaluation unit 56 by manually entering the weighed noil quantity and the weight of the cut combing sliver, i.e. the roving, or the roving length if the specific sliver weight is known or to be entered via the input field 58. The input of values as well as the information displayed on the display device 57 can in principle also be carried out via mobile devices such as smartphones, tablets, etc. or remotely. arranged stationary terminals in a central spinning mill can be entered and displayed. Steps 62 and 63 can be repeated several times during the reference run in order to increase the measurement accuracy of the noil proportion. Steps 62 and 63 are usually carried out one to three times.

The reference run preferably ends when the reference template has been used up or at least one of the lap rolls has run dry. The combing machine 1 is stopped. In step 65, the evaluation unit 56 creates a reference curve 64 from the detection variable continuously or discontinuously recorded during the reference run in step 61, which reflects the temporal progression of the detection variable over time during the reference run. If the delivery speed of the combing machine 1 was briefly reduced in one of the steps 62, 63 to determine the comber noil proportion, this can be taken into account or eliminated when creating the reference curve 64.

The reference curve 64 is shown in Figure 5 and represents the curve of the sensor output signal, in particular the output voltage of the sensor 54 assigned to the combing belt 3, over time t. The reference run starts at tsTART (step 60). The reference run ends at tEND (step 65). The time period At corresponds to the length of time or the total duration of the reference run.

In step 65, the reference curve 64 and the noil proportion determined in step 63 are linked to one another. The evaluation unit 56 stores the reference curve 64 together with the determined noil proportion. The reference curve 64 shown in Figure 5 is thus linked, for example, to a specific value, merely as an example to a noil proportion of 16 percent, end 66.

Figure 6 shows a flow chart of the combing process that follows the reference run. In step 70, the combing machine 1 starts the combing process and produces the combing band 3 from the material template 4 newly presented for the combing process. In step 71, the combing noil proportion stored in the evaluation unit 56 is reproduced as a display value on the display device 57.

In parallel, the detection device 55 detects the detection variable in step 72, here the sensor output signal U, in particular the output voltage of the sensor 54 assigned to the combing belt 3. In step 73, the actual curve 74, or the actual value of the continuously or discontinuously detected detection variable, is compared with the stored reference curve 64, as shown in Figure 7. If the actual curve 74 follows the reference curve 64, as shown by way of example at the times ti, t2, or at least remains within a predeterminable tolerance field, the width of which is indicated by the reference symbol 75, the combing noil portion is still valid 76 ("yes"), so that the strand 72, 73 is repeated and the display value, here 16 percent noil content as an example, continues to be displayed on the display device 57.

When the material supply 4 has been used up or at least one of the lap rolls 5 has run dry, as shown in Figure 7 at the time IEND, the combing machine 1 stops and the next material supply 4 can be presented. The combing process is restarted and the evaluation unit 56 starts the comparison of the actual curve 74 with the reference curve 64 again from the beginning, time to. This can be repeated as long as the actual curve

74 follows the reference curve 64 or remains within the tolerance range 75. As long as this is the case, the display value is shown on the display device 57, which, due to the boundary conditions remaining unchanged, still corresponds to the actual noil proportion that occurs during the combing process, in this case 16 percent as an example. A new determination of the noil proportion is therefore not necessary.

In Figure 8, for example, at time t2 it is shown that the actual curve 74 leaves the reference curve 64, but still remains within the tolerance field 75. At time _t3 the actual curve 74 also leaves the tolerance field 75. In the evaluation unit 56 a predetermined time interval can be started within which, when the actual curve 74 returns to the tolerance field 75, the strand is repeated with steps 72, 73. Only when the time interval has elapsed and the actual curve 74 is still outside the predetermined tolerance field 75, here at time t4, does the comparison show that the display value is invalid, step 76 "no", and the evaluation unit 56 generates a message signal in step 77 that the display value is invalid. The display value is then no longer displayed in order to avoid the operator assuming an incorrect noil proportion. Consequently, during the ongoing combing process, the boundary conditions influencing the sliver quality of the combing sliver 3 have changed to such an extent that the display value no longer reflects the actual amount of combing noil. The report signal is thus generated after a time period AtEVENT that is shorter than the length of the reference curve 64 with the time period At that was taught in during the reference run.

At end 78, a selection of possible actions can be suggested to the operator, such as ending the combing process in order to redetermine the noil proportion and the associated reference curve 64 in a new reference run, as shown in Figure 4.

If the combing machine 1 comprises the optional sensors 34, which are assigned to the individual combing head bands 29, the detection device 55 can detect their sensor output signals as detection variables and transmit them to the evaluation unit 56. Figure 9 shows a curve 80 of the respective sensor 34 over time of an alternatively possible reference run with the time period At, beginning with tsTARi and ending with IEND. The combing machine 1 has, here as an example, eight of the combing heads 2, so that the evaluation unit 56 receives the sensor output signals of the eight sensors 34 from the detection device 55 and the reference curve 64 created in step 65 has its own curve for each of the detection variables. The actual curve 74 of the respective detection variable in the combing process (start 70) can thus be compared with the associated curve 80 of the reference curve, see Figure 10. The same applies here in an analogous manner: if one of the actual curves leaves the associated curve 80 and is also outside the tolerance field 75 over the predefinable time interval, the evaluation unit 56 generates the message signal that the display value is invalid. Here too, as long as the signal is not generated, the combing process can be repeated as many times as required with new material templates 4.

Figure 11 shows the reference curve 64 from a further alternative reference run in which the detection device 55 detects the draft ratio V of the drafting system 36 as the at least one detection variable. The draft ratio can thus be used to check when the current noil proportion in the combing process deviates from the display value that shows the noil proportion on the display device. If the actual curve 74 of the draft ratio in the combing process follows the reference curve, as shown in Figure 12, or remains within the tolerance range 75, the boundary conditions have not changed or the display value continues to correspond to the current noil proportion. In a further embodiment, the detection device 55 can detect the sensor output signal of the sensor 54 assigned to the combing band as a further detection variable in addition to the draft ratio as a detection variable. Its sensor output signals would be largely constant over the time of the combing process when the draft is adjusted in the drafting system 36, as shown in Figure 14. The reference curve can thus have two curves, a first for the draft ratio and a second for the sensor output signal of the sensor 54 assigned to the combing band. If the sensor output signals of the sensor 54 assigned to the combing band deviate from the associated curve during the combing process and lie outside the tolerance field 75, the report signal is also generated.

Figure 13 shows the course of the draft adjustment of the drafting system 36 during a reference run according to a further embodiment. The draft adjustment was recorded with the recording device 55 and stored as a draft curve 81 in the evaluation unit 56. During the reference run, the sensor output signal of the sensor 54 assigned to the combing band 3 was recorded as the recorded variable and the reference course 64 according to Figure 14 was created from this. In the subsequent combing process, the drafting system 36 moves the quasi "frozen" distortion curve 81. During the combing process, the evaluation unit 56 compares the actual course of the sensor output signal of the sensor 54 assigned to the combing belt 3 with the reference course 64 from Figure 14, as shown in Figure 15, and generates the message signal if the actual course of the sensor output signal of the sensor 54 assigned to the combing belt 3 lies outside the predetermined tolerance field 75 of the reference course 64.

Figure 16 shows another combing machine 100 with, here as an example, twelve combing heads 2. The combing machine 100 differs from the previously described combing machine 1 only in the material feed 4, which here is a sliver feed made of fiber sliver cans 101. Accordingly, the combing heads 2 do not have any elements intended for the lap rolls 5, such as the winding rollers 8, 9. The above comments on the mode of operation and the method therefore also apply equally to the combing machine 100.

reference sign

1 combing machine 45 top roller

2 comb heads 46 top roller

3 combing belt 47 top roller

4 Material template 48 Top roller

5 cotton rolls 49 pre-draft field

6 cotton tape 50 main drafting field

7 Winding tube 51 Machine frame

8 Winding roller 52 Pressure element

9 Winding roller 53 Sensing roller pair

10 Take-off roller pair 54 Sensor

11 pair of calender rolls 55 detection device

12 Deflection roller 56 Evaluation unit

13 Feed cylinder 57 Display device

14 forceps apparatus 58 input field

15 Lever 59 Tape direction

16 Spring 60 Start

17 Pressure roller 61 step

18 levers 62 steps

19 lever 63 step

20 Wave 64 Reference Course

21 round comb 65 steps

22 comb segment 66 end

23 top comb 67 band forming funnel

24 combs

25 guide shaft 70 combing process

26 Extraction device 71 step

27 Suction channel 72 step

28 Solidification device 73 step

29 Single comb head band 74 Actual course

30 tear-off roller pair 75 tolerance field

31 tear-off roller pair 76 step

32 calender roll 77 step

33 Calender roll 78 End

34 Sensor

35 storage table 80 progression curve

36 drafting system 81 draft curve

37 compaction device

38 can storage 100 combing machine

39 Input roller pair 101 Sliver can

40 middle roller pairs

41 Output roller pair U Output voltage

42 Lower roller V draft ratio

43 lower roller

44 Lower roller

Claims

patent claims 1. Method for checking the validity of a display value during a combing process in which a combing machine (1; 100) produces a combing band (3) from a material template (4), the combing machine (1; 100) having a plurality of combing heads (2), each having a pliers apparatus (14) through which a cotton band (6) of the material template (4) presented to the combing head (2) can be passed, a circular comb (21) for combing out comb noils (24) from fiber tufts of the cotton band (6) clamped by the pliers apparatus (14), and a consolidation device (28) for forming a single combing head band (29) from the combed out fiber tufts; a suction device (26) for suctioning out the comb noils (24); a compression device (37) for combining the individual combing head bands (29) to form the combing band (3); an evaluation unit (56); a display device (57) coupled to the evaluation unit (56); and a detection device (55) coupled to the evaluation unit for detecting an actual course (74) of at least one time-varying detection variable that can be assigned to the combing band (3) and/or at least one of the individual combing head bands (29), and wherein the method comprises the following steps, which are carried out during the combing process of the material template (4): - displaying the display value on the display device, wherein the display value represents a noil proportion which is assigned to a reference curve (64) stored in the evaluation unit; Comparing the actual curve (74) of the at least one detection variable with the reference curve (64) by means of the evaluation unit; and - if the comparison shows that the actual curve of the at least one detection variable is at least temporarily outside a predetermined tolerance field (75) of the associated reference curve (64), generating a message signal (77) that the display value is invalid. 2. Method according to claim 1, characterized in that the reporting signal is only generated when the comparison shows that the actual course of the at least one detection variable lies outside a predetermined tolerance field of the associated reference course for longer than a predetermined period of time. 3. Method according to claim 1 or 2, characterized in that after the material template has been combed out, the combing process is repeated with new material templates until the reporting signal is generated. 4. Method according to one of claims 1 to 3, characterized in that after the generation of the signal, a current noil proportion is determined on the basis of a quantity of noils sucked out by the suction device and is newly assigned to the reference curve stored in the evaluation unit. 5. Method according to one of claims 1 to 4, characterized in that the reference course is created based on a reference run, during which a reference template is combed out with a reference wadding band for each combing head and the current combing noil proportion is determined. 6. Method according to claim 5, characterized in that the respective reference cotton band has a band length of more than 80 meters. 7. Method according to claim 5 or 6, characterized in that the reference run is carried out before the combing process and/or after generation of the reporting signal and/or when a boundary condition influencing the combing band changes, in particular delivery speed, number of combing cycles, quality of the cotton bands, for example a changed material composition or a changed mixing ratio. 8. Method according to one of claims 5 to 7, characterized in that the evaluation unit creates the reference curve from the actual curve of the at least one detection variable recorded during the reference run. 9. Method according to one of claims 1 to 8, characterized in that the detection device has a sensor assigned to the combing belt for detecting the at least one detection variable. 10. Method according to one of claims 1 to 9, characterized in that the detection device detects a sensor for each combing head assigned to the respective individual head combing band for detecting the at least one detection variable of the respective individual head combing band. 11. Method according to claim 9 or 10, characterized in that the at least one detection variable comprises a sensor output signal of the sensor assigned to the combing belt and/or the sensor assigned to the respective single-head combing belt, which the detection device transmits to the evaluation unit. 12. Method according to one of claims 9 to 11, characterized in that the sensor assigned to the combing belt and/or the sensors assigned to the respective individual head combing belt is/are from the group containing distance sensor, displacement sensor, tactile sensor, optical sensor, inductive sensor. 13. Method according to one of claims 1 to 12, characterized in that the combing machine has a drafting system for refining the individual head comb strips. 14. The method according to claim 13, characterized in that the detection device detects a draft ratio of the drafting system as the at least one detection variable. 15. Method according to claim 13, characterized in that the drafting system carries out a draft adjustment in order to achieve a uniform strip mass for the combing strip, the draft adjustment being recorded in the reference run and stored as a draft curve in the evaluation unit, the drafting system adjusting the draft according to the draft curve during the combing process. 16. Combing machine designed to produce a combing band from a material template, wherein the combing machine has a plurality of combing heads, each of which has a pair of pliers through which a cotton band of the material template presented to the combing head can be guided, a circular comb for combing out combing noils from fiber tufts of the cotton band clamped by the pair of pliers, and a consolidation device for forming an individual combing head band from the combed fiber tufts; a suction device for suctioning the combing noils; a compression device for combining the individual combing head bands to form the combing band; an evaluation unit; a display device coupled to the evaluation unit; and a detection device coupled to the evaluation unit for detecting an actual course of at least one time-varying detection variable assignable to the combing band and/or at least one of the individual combing head bands, characterized in that the combing machine is configured to carry out the method according to one of claims 1 to 15.