Method for verifying the validity of a display value during a combing process and combing machine
Patent Information
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- TRÜTZSCHLER GRP SE
- Filing Date
- 2024-05-29
- Publication Date
- 2026-04-15
Smart Images
Figure EP2024064825_12122024_PF_FP_ABST
Abstract
Description
[0001] Title: Method for checking the validity of a display value during a combing process and combing machine
[0002] Description
[0003] 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 sliver from a batting template, wherein the combing machine comprises a plurality of combing heads, each of which has a pincer device through which a batting of the batting template presented to the combing head can be guided, a circular comb for combing out noils from fiber tufts of the batting sliver clamped by the pincer device, and a consolidation device for forming an individual combing head sliver from the combed out fiber tufts, a suction device for suctioning the combing noils, a compression device for combining the individual combing head slivers to form the combing sliver, an evaluation unit,a display device coupled to the evaluation unit and a detection device coupled to the evaluation unit for detecting an actual profile of at least one time-varying detection variable attributable to the combing band and / or at least one of the individual combing head bands.
[0004] Yarn quality is determined, among other things, by the proportion of long fibers in the yarn. To influence this, combing machines are used in spinning preparation. These comb out a certain amount of short fibers, neps, trash, and dust from the feed wadding. For this purpose, wadding slivers from wadding feeds, which can include wadding reels or sliver feeds from sliver cans, are fed to the individual combing heads of the combing machine. When the wadding slivers are combed out by the circular combs of the individual combing heads, the resulting waste is called noil and is extracted by the combing heads using the suction device.
[0005] The current noil content can be determined based on the amount of noil extracted. For this purpose, in a process step usually carried out manually, the noil waste is intercepted within a certain time period at a central extraction system connected to the combing machine or directly at the combing machine using a slider that is inserted into a central extraction channel of the extraction device. Furthermore, the combing sliver produced by the combing machine during this time period is 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 combing noil and G is the weight of the cut-off combing sliver and the intercepted combing noil, then p = 100% of the combing noil content. The combing noil content represents the percentage share of the weight of the feed batting and the weight of the combing noil.Following the determination of the noil percentage, the combing process continues as usual, with the combed sliver being produced from the batting slivers provided in the material feed. However, since this determination is time-consuming and associated with costs for the spinning mill, the noil percentage is often only checked sporadically. This means that deviations from the last determined noil percentage can remain undetected for an extended period. The result is, for example, an excessively high noil percentage, which would lead to a poor utilization rate of the material feed. Causes for this, such as changes in the feed quality, wear and tear on combing head components, and the like, are therefore not detected and cannot be remedied. More frequent monitoring of the noil percentage could optimize the utilization rate and reduce unwanted waste, but is too labor-intensive due to the manual effort required.
[0006] WO 93 / 12278 A1 discloses an arrangement of sensors for automatically detecting the combed noils. DE 102006002390 A1 describes the corresponding adjustment options of the combing machine depending on the fiber quality.
[0007] In DE 102007039067 A1, each combing head of a combing machine is equipped with sensors that measure the weight of the lap before the combing head. The combed-out noils are removed via a suction system 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 measured data, with the difference supposedly corresponding to the mass of the combed-out noils. The noil percentage is displayed on a display.
[0008] The disadvantage of automatic noil detection is that its implementation in the combing machine is associated with high costs.
[0009] 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.
[0010] 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 profile of at least one time-varying detection variable that can be assigned to the combing sliver and / or at least one of the individual combing head slivers, 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 comber noil proportion that is assigned to a reference profile stored in the evaluation unit; comparing the actual profile of the at least one detection variable with the reference profile by means of the evaluation unit;and if the comparison shows that the actual curve of the at least one recorded variable lies at least temporarily outside a predetermined tolerance field of the assigned reference curve, generating a message signal that the noil portion is invalid.;
[0011] For the sake of better readability, "the at least one time-varying detection variable attributable to the combing belt and / or at least one of the individual combing head belts" is referred to as "the detection variable," whereby this continues to refer to precisely one detection variable or several of the detection variables. Where the exact number is important, this will be indicated at the appropriate point. It therefore goes without saying that the detection device can detect precisely one detection variable or several of the detection variables.
[0012] It has been determined that the detection variable during combing operation of the combing machine always follows a consistent curve over time, as long as no boundary conditions affecting the sliver quality of the combing sliver change during combing operation. These boundary conditions can include delivery speed, number of laps, quality of the laps and / or a changed material composition or mixing ratio, provision of laps from a different lap winder, defective or worn components of the combing machine, blockages in the combing head, etc. If the detection variable deviates from the usual curve, this is an indication that the noil proportion has changed. The operator can therefore assume that the noil proportion shown on the display device is valid until the actual curve of the detection variable deviates from the reference curve. This simplifies and optimizes the operation of the combing machine.It is therefore sufficient to monitor the actual course of the recorded variable in order to be able to make a statement about the validity of the displayed value, i.e. the correctness of the displayed noil proportion, by comparing it with the reference course. If the displayed value is valid, the actual course of the recorded variable 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 displayed value is invalid, the actual course of the recorded variable 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 based on events.Automating the event-driven noil detection is also possible with the appropriate implementation of automatic noil detection. For example, the temporary insertion of a pick-up device for picking up and / or collecting the noil in the extraction system can be automated, and the pick-up device can also be implemented using sensors, for example, using optical or inductive sensors in the extraction system.
[0013] To prevent the alarm signal from being generated even with the slightest deviation, deviations between the actual profile of the measured value and the reference profile are tolerated up to a certain extent. For this purpose, the tolerance field of the reference profile is stored in the evaluation device. The size of the tolerance field can be specified by the combing machine operator. Only when the alarm signal is generated is the operator alerted to the event that the displayed noil percentage is no longer valid.
[0014] Overall, there are several advantages, meaning that raw material savings can be achieved through optimally adjusted waste quantities. Influences such as supply fluctuations, raw material changes or altered comber settings are detected at an early stage. Incorrect comber settings can also be detected and rectified. Defective comber components, e.g. circular comb clothings, can be identified and replaced before a comber failure occurs. Not only can the combing process be analyzed seamlessly, but the noil proportion can also be documented over the comber's operating life, as corresponding data recording, in particular statistical evaluation, is possible, for example, as part of a quality management system, which can also be carried out using the evaluation unit.Another advantage is that, by additionally taking laboratory data into account, a correlation can be derived between the feed, combing sliver, and noil data, for example, the online recorded noil percentage and noil quality. This allows for continuous noil determination with minimal manual effort, since recalibration is only necessary when triggered by an event—namely, when the displayed value is invalid.
[0015] Furthermore, the actual curve can represent the variation of the measured value over time. The actual curve of the measured value can be compared with the reference curve continuously or discontinuously during the combing process, or at discrete time intervals, for example, at intervals of 1 second, 5 seconds, or 1 minute. The reference curve can represent a temporal variation of the measured value that the measured value follows over time under constant boundary conditions of the combing machine during the combing process.
[0016] When monitoring the recorded variable during the combing process, special situations may need to be taken into account that cause a change in the delivery speed of the combing machine, for example a can change, a machine stoppage, and the like. These special situations can lead to temporary deviations between the actual and the reference curve, which preferably do not result in the generation of an alarm signal. For example, an observation window can be specified during 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, for example, just three meters must be combed, that the delivery speed set for the combing process must be reached, that a minimum time must have elapsed, etc.In a similar way, an end point for the observation window can also be defined. This allows the observation window to close during a can change, for which the comber's delivery speed is reduced, and only reopen it when the set delivery speed is reached.
[0017] In a further development, the alarm signal can only be generated if the comparison shows that the actual curve of at least one recorded variable lies outside a specified tolerance range of the assigned reference curve for longer than a specified period of time. The period can be, for example, 1 second to 10 minutes. The extent to which the actual curve deviates from the reference curve can be taken into account. If the evaluation unit detects that the actual curve and the reference curve are increasingly diverging from each other, it can be provided that if a predefined threshold value, which may lie outside the tolerance range, is exceeded, the alarm signal is generated before the end of the specified period of time.
[0018] The material feed can be, in the usual way, a winding feed or a sliver feed from sliver cans. The procedure for loading the comber with a winding or sliver feed is usually predetermined in a spinning mill 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, during which all combing heads are again reloaded. Alternatively, the combing heads can also be loaded in blocks, so that, for example, on a 12-head comber, the first six combing heads are changed at the beginning of the combing process and the second six combing heads halfway through the combing process.
[0019] Furthermore, it can be provided that after the material feed has been combed out, the combing process is repeated with new material feeds until the warning signal is generated. The advantage is that, as long as the displayed value is valid, the displayed noil percentage corresponds at least substantially to the actual noil percentage, i.e., within the specified tolerances, and thus the combing process does not have to be interrupted to determine the noil percentage.
[0020] If the alarm 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.
[0021] After the alarm signal has been generated, a current noil proportion can be determined based on the amount of noil sucked away 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 similar. This allows the noil proportion stored in the evaluation unit to be replaced with the newly determined noil proportion. In principle, however, it can also be provided that the alarm signal is acknowledged manually in order to declare the displayed value valid again. This can be particularly useful after the repair or replacement of a defective component, the removal of a blockage on the combing head, or similar, since the combing process can and will then continue under the same boundary conditions.From the moment the current noil percentage has been reassigned to the reference curve or the signal has been acknowledged, the evaluation unit recognizes the noil percentage displayed on the display 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 signal. The current noil percentage is determined manually or automatically in a conventional manner.
[0022] The reference curve is preferably created based on a reference run. The reference run can take into account the current boundary conditions on the combing machine. It is advantageous if the reference run is as close as possible to the combing process with regard to the boundary conditions influencing the sliver quality of the combed sliver. In particular, the current comber noil proportion is determined during the reference run. This ensures that the comber noil proportion reproduced in the subsequent combing process indicates the last determined comber noil proportion, i.e. the current comber 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 comber produces a combed 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. For practical purposes, the reference template does not differ from the material template. It is also advantageous if the procedure for changing the reference template during the reference run corresponds to the procedure during the combing process, e.g. complete or block-wise change. The reference curve thus reflects the expected actual curve of the recorded variable in the combing process, provided the noil proportion remains constant during the combing process.Otherwise, the comparison will indicate that the displayed value is invalid, after which the current noil percentage can be re-determined. Preferably, the displayed value is no longer displayed until the new noil percentage is determined to prevent the operator from assuming an incorrect noil percentage.
[0023] The cotton ribbon quality of the reference cotton ribbons expediently corresponds to the cotton ribbon quality of the material template to be combed following 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 largely 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 provided 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.
[0024] In particular, the reference run is performed before the combing process and / or after the signal is generated and / or when a boundary condition influencing the combing sliver changes. This ensures that the displayed noil percentage always corresponds to the current noil percentage and, in particular, only needs to be determined if the displayed value is declared invalid due to a deviation of the actual profile of the measured value from the reference profile.
[0025] The evaluation unit can create the reference curve from the actual curve of the at least one detection 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 curve in the form of a curve over time. If several of the detection variables are recorded, the reference curve can have a separate curve for each of the detection variables. Thus, the actual curve of the respective detection variable can 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 recorded continuously or discontinuously.In this way, the respective sensor output signal can be used to create the reference curve using the sensor output signals recorded in the reference run, and to compare the actual curve of the sensor output signal with the reference curve during the combing process.
[0026] According to a first embodiment of the detection device, it can comprise a sensor assigned to the combing band for detecting the at least one detection variable. This sensor can be configured, 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 band passes. The first roller can, in particular, be spring-loaded and held movably relative to a second roller of the pair. The passing combing band can be further compressed between the pair of sensing rollers. The sensor assigned to the combing band can also be a tactile, inductive, or optical sensor. The sensor output signal can be proportional to a band mass of the outgoing combing band. However, it is advantageous that the evaluation unit does not need to be calibrated, since the comparison can be performed based on the directly detected sensor output signal.This means that it is sufficient to monitor the actual curve of the sensor output signal and compare it with the reference curve. However, an actual curve of a processed value that is derived from the sensor output signal, such as the sliver mass, sliver thickness, etc., can also be used for comparison with the reference curve. The sensor output signal viewed over time follows the reference curve during the combing process, even with each additional material feed, provided that the boundary conditions during the combing process remain constant and / or the noil proportion does not change. The sensor assigned to the combing sliver 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. The sensor assigned to the combing sliver can be in the range orbe arranged on or in the strip travel direction of the combing strip behind the compacting device and in particular at the strip exit 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 even a standard combing machine usually has such a detection device with a sensor assigned to the combing strip, 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, said sensor can be assigned to the respective individual-head combing strip for each combing head and for detecting the detection variable of the respective individual-head combing strip.The statements made 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 sliver is provided on each combing head. The respective sensor can correspond in design and function to the sensor assigned to the combing sliver. The sensor output signals of the sensors can be recorded during the reference run, whereby the reference profile can have its own profile curve for each sensor or for each of the detected variables. The actual profile of the respective detected variable can thus be compared with the associated profile curve of the reference profile. The sensors assigned to the individual combing head slivers can be arranged on or behind the respective bonding device of the respective combing head in the direction of strip travel.For example, the respective sensor can be arranged on a first roller of a roller pair, which is movably mounted relative to a second roller of the roller pair, in particular spring-loaded. The respective roller pair 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.
[0027] For all embodiments, it may further apply that the combing machine may have a drafting system for refining the single-head combed slivers. The drafting system may be arranged in the sliver travel direction between the bonding devices of the combing heads and the compacting device. The combing machine may comprise just one drafting system through which all of the single-head slivers are guided, or several, for example two, drafting systems, through each of which a subset of the single-head slivers is guided. The drafting system may have a main drafting zone and optionally at least one pre-drafting zone. For example, the drafting system may be designed as a three-over-three, four-over-three, four-over-four, or five-over-four drafting system.
[0028] 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 strip direction. 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, said device can detect a draft ratio of the drafting system as the at least one detection variable.This allows the draft ratio to be used to determine when the current noil ratio during the combing process deviates from the noil ratio displayed on the display unit. If the actual curve of the draft ratio during the combing process follows the reference curve, the boundary conditions have not changed, or the displayed noil ratio still corresponds to the current noil ratio. The ratio of the peripheral speeds of consecutively operating roller pairs of the drafting system can reflect the draft ratio.
[0029] If the detection variable includes the draft ratio, the sensor output signal of the sensor assigned to the combed sliver can be used as a further detection variable. Its sensor output signals, which can be proportional to the sliver mass of the outgoing combed sliver, will remain largely constant over the duration 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 combed sliver. Should the sensor output signals of the sensor assigned to the combed 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 noil proportion can no longer correspond to the current noil proportion, so that the warning signal can still be generated in this case.
[0030] If the drafting system is controlled, or the draft adjustment can be varied by changing the peripheral speeds of the input and / or output rollers, the sensor output signal from the sensor assigned to the combed sliver can be fed to the evaluation unit, for example, to compensate for long-wave periodic fluctuations in the individual head combed slivers fed to the drafting system. The drafting system can thus perform a draft adjustment to achieve a uniform sliver mass for the combed sliver.
[0031] 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 detected in the reference run and stored as a draft curve in the evaluation unit, wherein during the combing process the drafting system adapts 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 sliver and / or the sensors assigned to the individual combing head slivers. The detection variable of the respective sensor can be its sensor output signal, which, viewed over time, i.e. its actual curve, follows the reference curve. If a deviation is detected in the comparison, the corresponding alarm signal is generated.Due to the draft adjustment, which is intended to compensate for long-wave periodic fluctuations in the individual head combed slivers presented to the drafting system, the actual profile of the sensor output signal assigned to the combed sliver will correspond to a largely constant value. The respective sensor output signals can be recorded during the reference run, and the reference profile can be created based on this. If multiple sensors are used, this can have a separate curve for each of the detected variables. During the combing process, the actual profile of the detected variable assigned to the combed sliver can be used for comparison.
[0032] The process can thus be designed with a particularly simple detection device or rely on sensors 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 slivers, for example, by weighing individual cotton rolls, are not necessary with this process. As long as the actual profile of the detection variable follows the reference profile, the boundary conditions remain unchanged, or the reproduced noil fraction continues to correspond to the current noil fraction of the combing machine.
[0033] 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 sliver from a material feed, wherein the combing machine has a plurality of combing heads, each having a pincer apparatus through which a cotton sliver of the material feed presented to the combing head can be passed, a circular comb for combing out noils from fiber tufts of the cotton sliver clamped by the pincer apparatus, and a consolidation device for forming an individual combing head sliver from the combed-out fiber tufts; a suction device for suctioning off the combing noils; a compression device for combining the individual combing head slivers to form the combing sliver; an evaluation unit; a display device coupled to the evaluation unit;and a detection device coupled to the evaluation unit for detecting an actual profile of at least one time-varying detection variable attributable 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 results in 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 is understood that all of the aforementioned embodiments of the method are transferable to the combing machine and vice versa.
[0034] Further features and advantages of the invention will become apparent from the following description of preferred embodiments. Features that are essentially or functionally identical or similar are provided with the same reference numerals. They show:
[0035] Figure 1 is a representation of a combing machine according to the invention which produces a combing band from cotton bands of a winding template;
[0036] Figure 2 is a schematic representation of a combing head of the combing machine from Figure 1;
[0037] Figure 3 is a schematic representation of a drafting system of the combing machine from Figure 1;
[0038] Figure 4 is a flowchart 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 sliver are detected as the detection variable;
[0039] Figure 5 shows a reference curve created on the basis of the reference run from Figure 4;
[0040] Figure 6 is a flow chart of a combing process of the method using the combing machine of Figure 1;
[0041] 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;
[0042] Figure 8 shows the method step from Figure 7, whereby the comparison shows that the actual course of the detected variable lies outside a predetermined tolerance field of the reference course;
[0043] Figure 9 shows a reference profile 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 recording variable;
[0044] 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;
[0045] Figure 11 shows a reference profile created on the basis of a reference run of a method according to a third embodiment of the invention, wherein a draft ratio of a drafting system of the combing machine from Figure 1 is recorded as a recording variable during the reference run;
[0046] 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;
[0047] Figure 13 shows a draft adjustment of a drafting system of the combing machine from Figure 1, detected during a reference run of a method according to a fourth embodiment of the invention;
[0048] 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 of the combing machine from Figure 1 assigned to the combing sliver are recorded as the recording variable;
[0049] Figure 15 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 14, wherein during the combing process the drafting system adjusts the draft according to the draft curve from Figure 13; and
[0050] Figure 16 is a representation of a further combing machine according to the invention which produces a combing sliver from cotton slivers of a sliver feed from sliver cans.
[0051] Figure 1 shows a combing machine 1 with, here as an example, eight combing heads 2, which is designed in a conventional manner to produce a combing sliver 3 from a material feed 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.
[0052] The material template 4 is, in this case, 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 approximately 300 millimeters. Each cotton roll 5 has a cotton ribbon 6 wound on a winding core 7. The ribbon length of each cotton ribbon 6 is usually between 300 meters and 500 meters, but can in principle be between 80 meters and 1000 meters.
[0053] 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 strip 6 can be deflected at a deflection roller 12 and transferred to a feed cylinder 13 of a nipper apparatus 14. On the deflection roller 12, which is coupled here to a gear (not shown), a pressure roller 17 can be arranged, which is pivotably mounted about a lever 15 and loaded by a spring 16. This embodiment with the deflection roller 12, the lever 15 loaded by the spring 16, and the pressure roller 17 is preferably used only in an automatic lap application process and does not have to be a component of the combing machine 1.
[0054] The nipper apparatus 14 can be driven back and forth via levers 18, 19 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. This ratchet wheel is rotated step by step by a ratchet (not shown) as a result of the reciprocating movement of the nipper apparatus 14, thereby feeding the cotton sliver 6, in particular with an adjustable feed amount, to the jaws of the nipper apparatus 14 for combing. In a manner known per se, the cotton sliver 6 presented 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 below the nipper apparatus 14, which, via its comb segment 22, combs out the fiber tuft presented by the closed nipper apparatus 14. The circular comb 21 can also be drive-connected to 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 jointly to all comb heads 2 of the combing machine 1.
[0055] Adjacent to the nipper assembly 14 is a bonding device 28 for forming a single-comb head sliver 29 from the combed-out fiber tufts. According to the example shown in Figure 2, the nipper assembly 14 is in a forward position and transfers the combed-out fiber tuft to a downstream pair of tear-off rollers 30. The combed single-comb head sliver 29 then runs through another pair of tear-off rollers 31, a pair of take-off rollers 10, also called a delivery roller pair, and a pair of calender rollers 11 with a first calender roller 32 and a second calender roller 33, which are mounted so as to be movable relative to one another. A sliver forming funnel 67, for example, can be arranged above the pair of calender rollers 11. One of the two calender rollers 32, 33 can be spring-loaded and pivotably mounted, while the other can be stationary. The calender rolls 32, 33 serve to further consolidate the single combing head belt 29.
[0056] By detecting the distance between the two calender rolls 32, 33 or the magnitude 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 configured, for example, as a displacement or distance sensor. Other suitable sensor types are also possible, for example, to monitor the belt mass or thickness profile.
[0057] The individual combing head sliver 29, guided through the calender roller pair 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 slivers 29, in particular arranged side by side, are guided to a common drafting system 36. The eight individual combing head slivers 29, in this case, enter the drafting system 36, are drawn and doubled, for example by a factor of 18, and combined to form the combing sliver 3 by means of a compacting device 37, which can comprise a sliver funnel, for example. The combing sliver 3 can then be deposited in a can by means of a can depositor 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 cotton rolls 5, other fiber finenesses for the cotton bands 6, etc.than the values given here as examples are possible.
[0058] The drafting system 36 is shown in more detail in Figure 3. It is, in this case, a 2-zone drafting system or a 4-over-3 drafting system. It has three roller pairs 39, 40, 41, between which the drafting of the fiber composite from the individual combing head slivers 29 takes place: namely, in the sliver travel direction 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 a top roller 45, 46, 47, with a further top roller 48 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 zone 49. A subsequent main drafting zone 50 is formed by the middle roller pair 40 and the output roller pair 41.The lower rollers 42, 43, 44 are rotatably mounted on a machine frame 51 of the combing machine 1.
[0059] The drafting system 36 can be an uncontrolled or controlled drafting system. To regulate 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 via frictional engagement. In order to be able to monitor the combed 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 combed belt 3 can be arranged at the output of the drafting system 36.For example, one sensing roller can be pivotally movable and, in particular, spring-loaded relative to the other stationary sensing roller. The sensor 54 assigned to the combing belt 3 can, for example, be 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 roller pair 53 or the magnitude of the change in distance.
[0060] The combing machine 1 typically has sensors 34 assigned to the individual combing head slivers 29 and / or a sensor 54 assigned to the combing sliver 3. The sensors 34 and / or the sensor 54 belong to a detection device 55 of the combing machine 1, by means of which sliver quality characteristics of the individual combing head slivers 29 and / or the combing sliver 3 can be monitored. Furthermore, if the drafting system 36 is configured 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 sequentially 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 orthe peripheral speeds of the successively operating roller pairs 39, 40, 41 of the drafting system 36 are recorded.
[0061] 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 system of the combing machine 1, be part of the control system, or itself form the control system 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 be provided on the display device 57, via which the operator of the combing machine 1 can make inputs.
[0062] Figure 4 shows a flowchart of a reference run of a method according to a first embodiment of the invention. The reference run serves solely to obtain information and is intended to map the subsequent combing process, during which the combing machine 1 typically produces the combed sliver 3 from the provided material template 4 or the continuously re-presented material templates 4. The basic idea here is that the information obtained from the reference run should apply to the subsequent combing process(es). This information is repeatedly checked during the combing process. As soon as a deviation occurs, the operator of the combing machine 1 is informed.
[0063] With Start 60, the reference run starts, in which the combing machine 1 produces a combed sliver 3 from a provided reference lap template that corresponds to the properties of the material template 4, with the boundary conditions that also apply to the combing process, such as delivery speed, etc. The reference lap template has a lap sliver 5 with a reference lap sliver for each combing head 2.
[0064] During the reference run, in step 61, the detection device 55 detects the time-varying detection variable attributable to the combing belt 3, which 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.
[0065] In step 62, the amount of noil 24 accruing within a specific time period, which is sucked away by the suction device 26, is measured. For this purpose, the noil for the specific time period 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 during this time period is cut off. By subsequently weighing the cut-off combing sliver and the collected noil separately, the combing degree of the combing machine 1 can be determined in step 63. If K is the weight of the intercepted combing noil and G is the weight of the cut-off combing sliver and the intercepted combing noil, then p = 100% of the noil proportion. The noil content represents the percentage of the weight of the pre-spun cotton and the weight of the noil.The noil content is adjusted 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 results from the subsequent spinning of the combing sliver 3.
[0066] 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 combed 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 values as well as the information displayed on the display device 57 can, in principle, also be entered and displayed via mobile devices such as smartphones, tablets, etc., or remotely located stationary devices in a central spinning mill. Steps 62 and 63 can be repeated several times during the reference run to increase the measurement accuracy of the noil proportion. Typically, steps 62 and 63 are performed one to three times.
[0067] The reference run preferably ends when the reference supply is used up or at least one of the lap rolls has run dry. Combing machine 1 is stopped. In step 65, evaluation unit 56 creates a reference curve 64 from the detection variable continuously or discontinuously detected during the reference run in step 61. This reference curve represents the temporal progression of the detection variable over time during the reference run. If the delivery speed of combing machine 1 was briefly reduced in one of steps 62, 63 to determine the noil fraction, this can be taken into account or eliminated when creating reference curve 64.
[0068] 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 combed belt 3, over time t. The reference run starts at tsTART (step 60). The reference run ends at tEND (step 65). The time period Δt corresponds to the length or total duration of the reference run.
[0069] In step 65, the reference curve 64 and the noil percentage determined in step 63 are linked. The evaluation unit 56 stores the reference curve 64 together with the determined noil percentage. Thus, the reference curve 64 shown in Figure 5 is linked, for example, to a specific value—for example, a noil percentage of 16 percent—at the end of step 66.
[0070] Figure 6 shows a flowchart of the combing process following the reference run. In step 70, combing machine 1 starts the combing process and generates combed sliver 3 from the newly presented material template 4 for the combing process. In step 71, the combing noil percentage stored in evaluation unit 56 is displayed as a value on display device 57.
[0071] In parallel, in step 72, the detection device 55 detects the detection variable, here the sensor output signal U, in particular the output voltage of the sensor 54 assigned to the combing sliver 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 t1, t2, or at least remains within a predefinable tolerance field, the width of which is indicated by the reference symbol 75, the noil proportion continues to be valid 76 ("yes"), so that the strand 72, 73 is repeated and the display value, here by way of example 16 percent noil proportion, continues to be displayed on the display device 57.
[0072] When the material supply 4 is used up or at least one of the lap rolls 5 has run dry, as illustrated in Figure 7 at time IEND, the combing machine 1 stops and the next material supply 4 can be fed in. 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, at time t0. This can be repeated as long as the actual curve
[0073] 74 follows the reference curve 64 or remains within the tolerance range 75. As long as this value is maintained, the display value on the display device 57 remains. Due to the unchanged boundary conditions, this value still corresponds to the actual noil fraction generated during the combing process, in this example 16 percent. A new determination of the noil fraction is therefore not necessary.
[0074] Figure 8 shows, by way of example, at time t2, 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. A predefined time interval can be started in the evaluation unit 56, within which time interval the strand is repeated with steps 72, 73 when the actual curve 74 returns to the tolerance field 75. Only when the time interval has elapsed and the actual curve 74 continues to lie outside the predefined tolerance field 75, here at time t4, does the comparison result in the display value being 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 to prevent the operator from assuming an incorrect noil proportion.Consequently, during the ongoing combing process, the boundary conditions influencing the sliver quality of combing sliver 3 have changed to such an extent that the display value no longer reflects the actual noil content. The warning signal is thus generated after a time period ΔtEVENT that is shorter than the length of the reference curve 64 with the time period Δt learned during the reference run.
[0075] 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.
[0076] If the combing machine 1 comprises the optional sensors 34 assigned to the individual combing head belts 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 Δt, beginning with tsTARi and ending with IEND. The combing machine 1 has, here by way of 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 a separate curve for each of the detection variables. Thus, the actual curve 74 of the respective detection variable in the combing process (start 70) can be compared with the corresponding curve 80 of the reference curve, see Figure 10.Analogously, if one of the actual curves leaves the associated curve 80 and remains outside the tolerance zone 75 for the specified time interval, the evaluation unit 56 generates a signal indicating that the displayed value is invalid. Here, too, as long as the signal is not generated, the combing process can be repeated any number of times with ever new material templates 4.
[0077] 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. Thus, the draft ratio can be used to check when the current noil fraction in the combing process deviates from the display value representing the noil fraction 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 fraction. In a further embodiment, the detection device 55 can detect the sensor output signal of the sensor 54 assigned to the combing sliver 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 duration of the combing process with draft adjustment 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 sliver. Should the sensor output signals of the sensor 54 assigned to the combing sliver deviate from the associated curve during the combing process and lie outside the tolerance field 75, the warning signal is also generated.
[0078] 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 sliver 3 was recorded as the recorded variable, and the reference curve 64 shown in Figure 14 was created from this. In the subsequent combing process, the drafting system 36 traverses the quasi-frozen draft 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.
[0079] 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 in this case 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 apply equally to the combing machine 100.
[0080] Reference symbol
[0081] 1 combing machine 45 top roller
[0082] 2 combing heads 46 top roller
[0083] 3 Combing belt 47 Top roller
[0084] 4 Material feed 48 Top roller
[0085] 5 cotton rolls 49 pre-drafting field
[0086] 6 Cotton tape 50 main drafting field
[0087] 7 Winding core 51 Machine frame
[0088] 8 Winding roller 52 Printing element
[0089] 9 Winding roller 53 Pair of scanning rollers
[0090] 10 Take-off roller pair 54 Sensor
[0091] 11 Calender roller pair 55 Detection device
[0092] 12 Deflection roller 56 Evaluation unit
[0093] 13 Feed cylinder 57 Display device
[0094] 14 forceps apparatus 58 input field
[0095] 15 Lever 59 Tape running direction
[0096] 16 Spring 60 Start
[0097] 17 Pressure roller 61 step
[0098] 18 levers 62 steps
[0099] 19 lever 63 step
[0100] 20 Wave 64 Reference trend
[0101] 21 round comb 65 steps
[0102] 22 comb segment 66 end
[0103] 23 Top comb 67 Band forming funnel
[0104] 24 Combing
[0105] 25 Guide shaft 70 Combing process
[0106] 26 Suction device 71 step
[0107] 27 Suction channel 72 step
[0108] 28 Solidification device 73 Step
[0109] 29 Single combing head belt 74 Actual course
[0110] 30 tear-off roller pair 75 tolerance field
[0111] 31 tear-off roller pair 76 step
[0112] 32 Calender roll 77 step
[0113] 33 Calender roll 78 End
[0114] 34 Sensor
[0115] 35 storage table 80 progression curve
[0116] 36 Drafting system 81 Draft curve
[0117] 37 Compaction device
[0118] 38 Can rest 100 Combing machine
[0119] 39 Input roller pair 101 Sliver can
[0120] 40 center roller pairs
[0121] 41 Output roller pair U Output voltage
[0122] 42 Bottom roller V draft ratio
[0123] 43 Lower roller
[0124] 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 sliver (3) from a material feed (4), wherein the combing machine (1; 100) has a plurality of combing heads (2), each having a nipper apparatus (14) through which a cotton sliver (6) of the material feed (4) presented to the combing head (2) can be passed, a circular comb (21) for combing out noils (24) from fiber tufts of the cotton sliver (6) clamped by the nipper apparatus (14), and a bonding device (28) for forming an individual combing head sliver (29) from the combed-out fiber tufts; a suction device (26) for suctioning off the combing 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 profile (74) of at least one time-varying detection variable assignable to the combing belt (3) and / or at least one of the individual combing head belts (29), and wherein the method comprises the following steps, which are carried out during the combing process of the material feed (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 lies 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 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 alarm 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 away by the suction device and is re-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 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 signal and / or upon change of a boundary condition influencing the combing band, in particular delivery speed, number of comb 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 individual 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 comprising 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 single-head comb slivers.
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 sliver mass for the combed sliver, 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. A combing machine designed to produce a combing sliver from a material feed, wherein the combing machine comprises a plurality of combing heads, each having a pincer device through which a cotton sliver of the material feed presented to the combing head can be passed, a circular comb for combing out noils from fiber tufts of the cotton sliver clamped by the pincer device, and a consolidation device for forming an individual combing head sliver from the combed-out fiber tufts; a suction device for suctioning the combing noils; a compression device for combining the individual combing head slivers to form the combing sliver; 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.