Method for adjusting gram weight of sliver in integrated drafting mechanism of carding machine

Abstract

The invention relates to a method for adjusting the basis weight of a sliver (FB) in an integrated drafting unit (1) of a carding machine (K), having an input measuring roller pair (6a, 6b) located upstream of a main drafting zone of the drafting unit and having an output measuring roller pair (15a, 15b) located downstream of the main drafting zone, the basis weight of the sliver (FB) at the input measuring roller pair (15a, 15b) forms a given parameter and the draft multiple of the draft mechanism forms an operating parameter, a change in the basis weight of the sliver (FB) at the input measuring roller pair (6a, 6b) causes a change in the operating parameter in a control unit of the carding machine (K), and the change in the basis weight of the sliver (FB) at the input measuring roller pair (6a, 6b) causes a change in the operating parameter. The change amount of the operating parameter is stored in a controller of the carding machine (K) by means of a pattern or a curve, which is formed by at least two parameters. The invention also relates to a drafting mechanism for carrying out the method.

Description

Technical Field

[0001] This invention relates to a method for adjusting the basis weight of fiber slivers in an integrated drafting mechanism of a carding machine. Background Technology

[0002] Fiber slivers produced in a carding machine typically do not have a constant sliver weight at the output end. This is primarily due to the specific weight fluctuations of the fed fiber bundles and the varying degrees of contamination in the raw materials, which should be eliminated through the carding process. An integrated drafting unit located downstream of the carding machine should place fiber sliver coils with a constant weight in a sliver can changer to produce uniform yarn in subsequent air-jet spinning processes. Due to space constraints, the integrated drafting unit does not have a pre-drafting mechanism but only a main drafting zone, which is configured, for example, by a 2-up-2-down drafting mechanism or a 2-up-3-down drafting mechanism. According to existing technology, the draft ratio adjustment is performed manually and cumbersomely, only when a large and new fluctuation in the sliver weight is anticipated, such as when changing material batches. In this process, the sliver weight is measured before entering the main drafting zone, and the desired sliver weight and draft ratio at which it should enter the sliver can are manually calculated. The calculated coefficient for adjusting the draw ratio is input into the carding machine's controller, ensuring that the integrated draw unit is adjusted, at least for this batch of material. Unrelated to the above, the integrated draw unit can adjust for small weight fluctuations, but only within a certain range. Summary of the Invention

[0003] The objective of this invention is to automatically adjust the main drafting zone of the integrated drafting device in order to compensate for weight fluctuations of the carded sliver within a large adjustment range.

[0004] The present invention solves the proposed task by a method having the features given in claim 1 and a drawing mechanism having the features of claim 6. Advantageous extensions of the invention are defined in the dependent claims.

[0005] This invention relates to a method for adjusting the basis weight of a fiber sliver in an integrated drafting mechanism of a carding machine. The drafting mechanism has an input measuring roller pair located before the main drafting zone and an output measuring roller pair located after the main drafting zone. In the first calibration, the adjusted sliver weight at the output measuring roller pair constitutes a given parameter. The draft ratio of the drafting mechanism is adjusted using the determined incoming sliver weight at the input measuring roller pair to produce the desired sliver weight for the coiler in the sliver can. The draft ratio of the drafting mechanism—as known from the prior art—is changed by increasing or decreasing the rotational speed of the drive that drives the lower roller of the drafting mechanism. This data is stored in the controller of the carding machine, and this data forms the basis for subsequent adjustment methods.

[0006] However, in subsequent operation, the basis weight of the fiber sliver at the input measuring roller pair constitutes a given parameter, and the draft ratio of the drafting mechanism constitutes an operating parameter. A change in the basis weight of the fiber sliver at the input measuring roller pair will result in a change in the operating parameter in the carding machine's controller. The amount of change in the operating parameter is stored in the carding machine's controller as a graph or curve, formed by at least two parameters. The main drafting zone is constituted by a 2-up-2-down drafting mechanism or a 2-up-3-down drafting mechanism. Here, the first and second drafting roller pairs each have their own drivers, which can be controlled independently of each other by the carding machine's controller. To change the draft ratio, the rotational speed of only one driver or both drivers can be changed. When the change in the draft ratio is generally described here, those skilled in the art will understand that the control drivers are used to adjust the rotational speed of the drafting mechanism rollers.

[0007] Here, a first parameter is formed by creating a graph or curve using the adjusted draft ratio of the drafting mechanism under preset, given parameter conditions. The aforementioned data is used for calibration. At least one second parameter is formed by changing the draft ratio by either increasing or decreasing the basis weight of the fiber sliver at the input measuring roller pair. Another third parameter can be formed by changing the draft ratio by decreasing the basis weight of the fiber sliver at the input measuring roller pair, which differs from the basis weight of the fiber sliver under the second parameter condition. If an increased sliver weight is used when determining the second parameter, a decreased sliver weight is considered in the third parameter condition. Therefore, the graph is formed by at least two parameters or points, allowing interpolation of the corresponding draft ratio when the basis weight of the fiber sliver deviates from these two points. In the case of three parameters, a curve can be stored in the carding machine's controller that more accurately maps changes in draft ratio when there is a deviation in the incoming sliver weight. Adjustments become more precise by increasing the number of parameters, for example, to 5, 7, 9, or more. For automated operation during batch changes at the carding machine, practice has shown that the two parameters are accurate enough, as the time consumed for calibration of this method is reasonable.

[0008] Because the change in operating parameters occurs directly when there is a deviation from the given parameters (the sliver weight at the input measuring roller pair during operation), the weight fluctuation of the fiber sliver coiled in the can is relatively small. Alternatively, the operating parameters can be changed after a preset resting time (which is adjustable in the carding machine's controller according to the fiber sliver supply speed), which is gentler on the fibers to be treated.

[0009] The basis weight (FB) of the fiber sliver used at the input measuring roller pair (6a, 6b) can differ from the preset basis weight (FB) of the fiber sliver (FB) at the input measuring roller pair (6a, 6b) by ±50% in order to determine the pattern or curve. A difference of ±30% is preferred. This width of basis weight deviation of the fiber sliver can cover a very large fluctuation range, which is rare in produced carded slivers.

[0010] The drafting mechanism according to the invention is configured to draft a single carded fiber sliver, which is generated in a carding machine and continuously enters the drafting mechanism. The drafting mechanism has an input measuring roller pair in the material flow direction, the input measuring roller pair having a sensor for determining the basis weight of the fiber sliver. Downstream in the material flow direction, only a 2-up-2-down drafting mechanism or a 2-up-3-down drafting mechanism with a main drafting zone is arranged, and downstream in the material flow direction, an output measuring roller pair is provided, the output measuring roller pair having a sensor for determining the basis weight of the fiber sliver. The drafting mechanism is controlled by a controller of the carding machine and configured to operate the method according to any one of the preceding claims.

[0011] This drafting mechanism has a first drafting roller pair and a second drafting roller pair, wherein each drafting roller pair is assigned its own controllable driver for adjusting the draft ratio. These drivers can be controlled individually by the carding machine's controller or together to change the draft ratio.

[0012] Preferably, the output measuring rollers are configured to transport the fiber sliver to the sliver can changer. This keeps the structural dimensions of the drafting mechanism compact. Attached Figure Description

[0013] Other measures to improve the invention are described in detail below with reference to the accompanying drawings and a description of preferred embodiments of the invention.

[0014] In the picture:

[0015] Figure 1 A carding machine with a subsequent sliver coiler and an integrated drafting unit is shown;

[0016] Figure 2 A front view of the main components of the drawing device according to the present invention is shown;

[0017] Figure 3 A rear view of the traction device with a drive assembly is shown. Detailed Implementation

[0018] Here Figures 1 to 3The drafting mechanism shown is exemplarily illustrated as a 2-up, 2-down drafting mechanism. However, the drafting mechanism can also be configured as a 2-up, 3-down drafting mechanism. Here, the method and apparatus exclude the use of a pre-drafting zone because, in this case, both pre-drafting and main drafting must be further adjusted simultaneously, which would complicate the adjustment process.

[0019] Figure 1 A carding machine K is shown, in which the produced fiber sliver FB is guided to a drafting mechanism 1 by a plurality of steering rollers R. The drafting mechanism 1 is arranged above and integrated into a sliver can changer W, and thus is an integral part of the carding machine K. In this embodiment, a sliver accumulator S for the fiber sliver FB is arranged between the carding machine K and the drafting mechanism 1, the accumulator being configured to at least partially compensate for the difference in the supply speed of the fiber sliver FB between the carding machine K and the drafting mechanism 1. The use or arrangement of the accumulator S is not important to the invention. For better understanding of the subsequent arrangement of the components, a Cartesian coordinate system is used here, where the z-direction is the vertical line in which the fiber sliver FB enters the drafting mechanism 1. The y-direction corresponds to the longitudinal axis of the drafting roller in subsequent figures, and the x-direction is oriented orthogonally to the longitudinal axis of the drafting roller. It is important for the invention that the individual fiber sliver FB enters the drafting mechanism 1 vertically (in the z-direction) by gravity.

[0020] Figure 2This is a first front view of the drafting mechanism 1 after the cover 2 and flap 3 have been removed. Only the front of the upper drive housing 4a is visible; according to other figures, this drive housing extends further after the arrangement of the rollers and funnels, but is not shown here. The fiber sliver FB (not shown here) enters vertically (in the z-direction) into the first funnel 5 and is detected by the input measuring roller pair 6a, 6b. The funnel 5 is configured to pivot upwards in the vertical direction (Z-direction) away from the input measuring roller pair 6a, 6b to allow cleaning of subsequent input measuring roller pairs 6a, 6b or to eliminate erroneous start-ups. The subsequent input measuring roller pair 6a, 6b is configured to detect deviations of the fiber sliver FB from a preset sliver weight and transmit the measurement value to a controller (not shown) for display, which could be, for example, the controller of a cover-type carding machine K. For this purpose, the input measuring roller 6b is rotatably supported in a fixed position, while the second input measuring roller 6a is movably supported relative to the first input measuring roller 6b. The displacement of the second input measuring roller 6a can be detected using, for example, a movable coil or other sensor, and the displacement change can be converted into a weight deviation. Not further shown, scraper-type roller cleaners can be arranged on both sides of the input measuring roller pair 6a, 6b to clean the surfaces of the input measuring rollers 6a, 6b. The input measuring roller pair 6a, 6b can be configured as grooved rollers / probe rollers or stepped rollers, or include two smooth rollers. A stripper 16 or other guiding element can be arranged below the measuring roller 6b on the left side shown in this view, used to separate the fiber sliver FB from the input measuring roller pair 6a, 6b and introduce it into the first drafting roller pair 7, 8. A lever (not shown) can eliminate the pressure load (not shown) on the movable input measuring roller 6a, which can be used to move the input measuring roller 6a away from the fixedly positioned input measuring roller 6b. This makes maintenance and cleaning of the input measuring roller pair 6a, 6b and the upper drafting roller pair 7, 8 arranged below them easier.

[0021] The fiber sliver FB continues to run vertically downwards until it is captured by the first lower roller 7 and the first upper roller 8. The first lower roller 7 is driven by a first driver 21, which can be configured as an adjusting driver. These two rollers 7 and 8 form the first drafting roller pair. The fiber sliver FB, with a slight offset against the x-direction, encounters the pressure bar 13, is guided past the pressure bar, and reaches the second drafting roller pair formed by the second lower roller 9 and the second upper roller 10. Thus, the drafting mechanism 1 shown here is configured as a vertically arranged 2-upper-2-lower drafting mechanism (single-zone drafting mechanism), having two lower rollers 7 and 9 and two upper rollers 8 and 10. Although the drafting roller pairs are arranged vertically to each other, the upper and lower rollers are analogous to those in a conventional drafting mechanism with a horizontal material flow direction of the fiber sliver, because the lower roller has a grooved surface of metal, and the upper roller is provided with a plastic or rubber cover. Due to the different rotational speeds, the fiber sliver FB is drafted in length by the first and second drafting roller pairs and is fed into the second funnel 14. Furthermore, the first and second cylinders 11a and 12a are visible, which are used to press the upper rollers 8 and 10 at one end against the x-direction by the pistons of the cylinders 11a and 12a onto the lower rollers 7 and 9. The second lower roller 9 is driven by another driver 30, which can be controlled independently of the first driver 21. Thus, the two roller pairs 7 and 8 and 9 and 10 are driven independently of each other, making the draft ratio in the main drafting zone adjustable.

[0022] Funnel 14 is configured as a sliver-forming aid and has swirling nozzles along its inner bore, through which compressed air flows. This creates suction at the funnel opening, drawing the fiber sliver FB into the funnel and guiding it to the output measuring roller pairs 15a and 15b. The output measuring roller pairs 15a and 15b are also configured to detect deviations in sliver weight from preset values. A fixed first output measuring roller 15a cooperates with a movably supported second output measuring roller 15b. Changes in the distance between the second output measuring roller 15b and the fixed first output measuring roller 15a are converted into sliver weight deviation values ​​by a sensor (e.g., in the controller of a cover carding machine). These values ​​are also transmitted to the controller (e.g., the controller of a cover carding machine), which compares these values ​​with those of the input measuring roller pairs 6a and 6b and displays them on a screen. The output measuring roller pairs 15a and 15b can be configured as smooth roller pairs, grooved roller pairs / detector roller pairs, or rollers with stepped sections. Not further shown, scraper-type roller cleaners can be arranged on both sides of the output measuring roller pair 15a, 15b to clean the surface of the measuring rollers. A pressure load (not shown) on the movable output measuring roller 15a can be eliminated by lever 36b, which allows the output measuring roller 15a to move away from the fixedly positioned output measuring roller 15b. This makes maintenance and cleaning of the output measuring roller pair 15a, 15b and the coiled tube 40 arranged below them easier. In Figure 5, lever 36b is shown in the locked position for the movable output measuring roller 15a.

[0023] After the output measuring rollers 15a, 15b, the drafted fiber sliver FB is coiled in a sliver can (not shown) in a cycloidal shape via a known coiling tube 40 that rotates via a sliver can turntable 41. A sensor 17 is arranged between the output measuring rollers 15a, 15b and the coiling tube 40, which is configured to monitor for possible sliver blockage at the inlet or opening of the coiling tube 40.

[0024] The signals from the input measuring roller pairs 6a and 6b and the output measuring roller pairs 15a and 15b can be processed in the controller of the carding machine K or the controller of the spinning preparation equipment. When the automatic sliver generation process proceeds smoothly, the controller can output a signal. Thus, the two measuring roller pairs 6a and 6b, and 15a and 15b, will generate regular signals regarding the sliver weight. If, after automatic sliver generation, only the input measuring roller pairs 6a and 6b display stable signals, while the output measuring roller pairs 15a and 15b do not display regular signals or display significantly changing signals, it indicates that the fiber sliver FB has broken. When there is a deviation in the set sliver weight at the input measuring roller pairs 6a and 6b and the output measuring roller pairs 15a and 15b, the controller of the carding machine is configured to control the driver 21 and / or driver 30 to adjust the draft ratio.

[0025] To introduce the fiber sliver FB into the drafting mechanism 1, the carding machine K operates at a low supply or running speed, for example, the speed of the escaping fiber sliver, between 10 m / min and 100 m / min. Preferably, the carding machine speed is between 10 m / min and 50 m / min. The carded fiber web is conveyed by the doffer of the carding machine, for example, to a subsequent transverse belt or pull-out roller, and is guided into an integrated funnel. The subsequent measuring roller at the output end of the carding machine is capable of detecting the sliver weight of the formed fiber sliver FB or the deviation of the fiber sliver weight from a reference value, and the corresponding signal is processed in the carding machine controller. If the sliver weight is detected, the controller of the carding machine K automatically starts the drafting mechanism 1 by driving the input measuring rollers 6a and 6b, the drafting roller pairs 7 and 8; 9 and 10, and the output measuring roller pairs 15a and 15b, via drivers 21 and 30. Locking the drafting mechanism 1 activates the pneumatic load on the upper rollers 8 and 10. Simultaneously, the driver 30 rotates the sliver can turntable 41 of the sliver can changer W. The operator manually removes the fiber sliver FB escaping from the carding machine K and, with the cover 2 closed, introduces it through opening 3a into the first funnel 5 at the top of the drafting device 1. Here, the starting end of the fiber sliver FB is captured by the input measuring rollers 6a and 6b and pulled into the drafting device 1. Upon detection by the input measuring rollers 6a and 6b, the corresponding sensor sends a signal to the controller of the carding machine K, which generates compressed air to create suction at the second funnel 14. Suction assists the insertion of the fiber sliver FB, which is captured and pulled in by the first drafting rollers 7 and 8. Due to the horizontal offset of the drafting roller pairs 7, 8; 9, 10, the fiber sliver FB impacts the side of the pressure bar 13 and is guided to the upper wedge-shaped opening of the second drafting roller pair 9, 10, where it is captured and drawn into the second funnel 14 by suction. The rotational motion of the drafting roller pairs 7, 8; 9, 10 also generates airflow within the drafting mechanism 1, which facilitates automatic insertion. Subsequently, the fiber sliver FB can be captured by the output measuring roller pairs 15a, 15b and guided into the coil tube 40, which is then conveyed to the already rotating sliver can turntable 41. When the fiber sliver is detected by the output measuring roller pairs 15a, 15b, the corresponding sensor can send a signal to the controller of the cover carding machine K. The controller recognizes the insertion of the fiber sliver as successful and can stop introducing compressed air into the second funnel 14. Simultaneously, the supply speed of the cover carding machine is increased to the operating speed necessary for the fiber basis weight without operator intervention. In addition, the speeds of the drafting device 1 and the can changer W are also adjusted according to the production speed or supply speed of the carding machine.

[0026] If automatic threading fails, for example due to sliver breakage or blockage, it can be identified by either no fiber sliver entering the sliver can through the coil tube 40, or the output measuring roller pairs 15a, 15b fail to send a signal to the controller of the carding machine K. If the output measuring roller pairs 15a, 15b fail to send a signal to the controller of the carding machine within, for example, 1 to 5 seconds after the sensors of the input measuring roller pairs 6a, 6b detect the fiber sliver, the controller of the carding machine shuts down the drafting mechanism 1. Alternatively, in the event of sliver blockage or breakage, sensor 17 can send a signal to the controller of the carding machine to interrupt the automatic threading process. The drafting device 1 and the sliver can changer W stop, while the carding machine K continues to operate at a lower supply or running speed. Thus, it continues to operate slowly but continuously outputs fiber slivers from the carding machine. The drafting device 1 is unlocked, and the pressure load on the upper rollers 8, 10 is removed. The cover 2 of the drafting device 1 is opened, and sliver residue can be removed. With the cover 2 of the drafting device 1 closed, locking is performed, i.e., pressure load is applied to the upper rollers 8 and 10. Simultaneously, the drives 21 and 30 activate the input measuring roller pairs 6a and 6b, the drafting roller pairs 7, 8, 9, and 10, and the output measuring roller pairs 15a and 15b. The fiber sliver FB from the cover carding machine K can be reintroduced into the upper first funnel 5, and the automatic sliver generation process restarts.

[0027] When changing the sliver can, also initiated by the controller of the cover carding machine K, compressed air for suction can be introduced into the second funnel 14 before a thin spot is formed in the fiber sliver FB. After the fiber sliver FB breaks at the thin spot, compressed air continues to be generated until the fiber sliver FB is captured at least again by the output measuring rollers 15a, 15b. The timing of injecting compressed air into the second funnel 14 before and after the thin spot is formed in the fiber sliver FB can be adjusted in the controller of the cover carding machine K. In addition to the output measuring rollers 15a, 15b, a puller roller can also be used to guide the fiber sliver FB into the coil tube 40.

[0028] For sliver can replacement, thin spots are generated in the main drafting zone, between drafting roller pairs 7, 8 and 9, 10, via two drives 21 and 30. The length and intensity of the thin spots are adjusted in the controller of the carding machine K. To this end, for the upcoming sliver can replacement time, the drives 21 and 30 of the first and second lower rollers 7, 9 are adjusted at significantly different speeds to generate drafting between the drafting roller pairs 7, 8 and 9. The drive of the second lower roller 9 can be adjusted to a higher speed, or the drive of the first lower roller 7 can be adjusted to a lower speed. Preferably, the drive of the second lower roller 9 is adjusted to a higher speed so that during return, it is not necessary to adjust the feed speed of the sliver accumulator S and the carding machine.

[0029] The draft ratio in the drafting mechanism is adjusted on the controller of the carding machine K. Here, in the first step, the desired process parameters, such as the feed rate, are calibrated, and the sliver weight and target draft ratio at the output measuring roller pairs 15a and 15b are adjusted as given parameters. Since the fiber sliver in the carding machine fluctuates in weight, the draft ratio (operating parameter) in the drafting mechanism must be adjusted to achieve the given parameters. Then, a standard balancing process is performed during the operation of the carding machine K and the drafting mechanism 1 to produce the desired sliver size. Feedback to the controller of the carding machine K is achieved through signals from the input measuring roller pairs 6a and 6b and the output measuring roller pairs 15a and 15b, thus enabling control of the input.

[0030] When a deviation occurs in the sliver weight at input measuring rollers 6a and 6b, the controller of the carding machine must very quickly change the draft ratio of the operating parameter to ensure a constant sliver weight, for example, 5 ktex, enters the can at output measuring rollers 15a and 15b, using the given parameter setting. To do this, the controller will be calibrated as follows:

[0031] In the second step, the target values ​​for the input measuring rollers 6a and 6b are continuously and slowly increased by a defined coefficient, so that a heavier sliver is delivered to the integrated drafting mechanism 1, for example, the sliver weight can be increased by 30%, so that production is carried out at 6.5 ktex instead of 5 ktex in the carding machine.

[0032] By controlling the carding machine K, the draft ratio, a key parameter in the drafting mechanism 1, is gradually increased to balance the weight fluctuation. This means controlling the first drive 21 to operate at a lower speed for the first lower roller 7, and / or controlling the second drive 30 to operate at a higher speed for the second lower roller 9. If the draft ratio change is too small, a positive deviation is determined at the output measurement system. If the draft ratio change is too large, a negative deviation is determined at the output measurement system.

[0033] After reaching the target value (e.g., +30%) of the input measuring roller pairs 6a and 6b, the drafting ratio of the drafting mechanism is slowly adjusted until the average output deviation is minimized. The change in drafting ratio between the 6.5 ktex sliver weight at the input measuring roller pairs 6a and 6b and the re-achieved 5 ktex sliver weight at the output measuring roller pairs 15a and 15b, i.e., the adjustment value of the driver 21 and / or driver 30, is stored in the controller. The value calibrated by the controller, as well as the adjustment and storage of the drafting value in the case of increased incoming fiber sliver weight (second step), forms the first basis for automatic adjustment of the drafting mechanism during operation. Using these two values, a pattern is stored in the controller of the carding machine, which forms an adjustment of the drafting ratio when a deviation occurs in the sliver weight at the input measuring roller pairs 6a and 6b, without the carding machine controller waiting for and processing the signal from the output measuring roller pairs 15a and 15b after adjusting the path (the process of the fiber sliver passing through the drafting mechanism).

[0034] In an optional third step, the target values ​​of the input measuring roller pairs 6a and 6b can be continuously and slowly reduced by a defined coefficient, such that an excessively light sliver is delivered to the integrated drafting mechanism 1 via the cover carding machine K, with a sliver weight, for example, only 3.5 ktex instead of 5 ktex, e.g., -30%. During this period, the drafting mechanism 1 reduces the drafting ratio, a control parameter in the drafting mechanism, to balance this weight fluctuation. Similarly, the drafting ratio in the drafting mechanism 1 is slowly reduced via the controller of the cover carding machine K to balance this weight fluctuation. This means controlling the first drive 21 to operate at a higher speed for the first lower roller 7, and / or controlling the second drive 30 to operate at a lower speed for the second lower roller 9. Here, if the drafting ratio change is too small, a negative deviation will appear at the output measuring roller pairs 15a and 15b. If the drafting ratio change is too large, a positive deviation will appear in the output measuring system. After the target value (e.g., -30%) of the input measuring roller pairs 6a and 6b is reached, the drafting ratio of the drafting mechanism's operating parameters is slowly adjusted until the average output deviation is minimized. The change in the drafting ratio between the 3.5 ktex strip weight at the input measuring roller pairs 6a and 6b and the re-achieved 5 ktex strip weight at the output measuring roller pairs 15a and 15b, i.e., the adjustment value of the drive 21 and / or drive 30, is stored in the controller.

[0035] The values ​​in the second and third steps can also be interchanged, that is, the fiber weight is reduced in the second step and increased in the third step.

[0036] Using these two parameters (steps one and two), a linear graph is obtained, or using a third parameter (step three), a variation curve is generated in the graph, which is stored in the controller of the carding machine. Based on the graph or variation curve, the controller can immediately control one or both drives 21 and 30 based on the deviation of the sliver weight at the input measuring roller pairs 6a and 6b to achieve the preset sliver weight at the output measuring roller pairs 15a and 15b. Therefore, the variation curve corresponds to the operating parameters to adjust the adjustment deviation from the given parameters. The change in draft ratio, which is performed slowly during the calibration in steps two and three, can now be performed directly and immediately.

[0037] This means that the controller directly changes the stored value or coefficient of the draft ratio, a key parameter, to allow the target strip weight (given parameter) to be coiled in the strip can using the short adjustment path between the input measuring roller pair 6a, 6b and the output measuring roller pair 15a, 15b. The parameterization of the draft controller is now optimized based on at least two operating points. Instead of at least two operating points, multiple operating points, such as 3, 5, 7, or 9, can be determined to more accurately determine the variation curve of the given parameter and precisely interpolate possible deviations.

[0038] When the sliver weight changes at input measuring rollers 6a and 6b, the drafting ratio of the drafting mechanism can be changed directly and immediately through the controller of the cover carding machine, or relatively slowly after a preset resting time, so that the deviation at output measuring rollers 15a and 15b remains small and does not compromise the customer's gram weight requirements.

[0039] Figure 3 The back side of the drafting device according to the invention, with its drive scheme, is shown. The upper drive housing 4a is completely separate from the lower drive housing 4b and can be moved along the guide plate 24 by means of an adjusting element 23 (not shown), allowing adjustment of the clamping line distances L1, L2 without individually adjusting the drafting rollers 7, 8, 9, 10. Both the upper drive housing 4a and the lower drive housing 4b have separate, independent drives that are not affected by the adjustment of the clamping line distances. Since all drive assemblies are arranged on the back side of the drafting device, a freely accessible front side is provided, offering ample space for maintenance or cleaning. Therefore, there is no need to disassemble or adjust the drive assemblies. Additionally, the disassembly of the upper rollers 7, 9 is further facilitated by the support scheme of the upper rollers 7, 9 (where the front cylinders 11b, 12b are arranged in opposite directions to the rear cylinders 11a, 12b). If the upper rollers 7, 9 are disassembled, ample free space is created on the remaining drafting mechanism assemblies for maintenance and cleaning.

[0040] The upper drive housing 4a has a first drive 21, which drives an adjustable second input measuring roller 6b and a first lower roller 7 via a first belt 26. Here, the second belt 28 drives the first input measuring roller 6a via the driven second input measuring roller 6b and is deflected via a steering roller 29. The driving directions of the first and second input measuring rollers 6a and 6b are opposite, such that the fiber sliver FB is transported vertically downwards through the input measuring rollers 6a and 6b. A sensor 27 is arranged on the fixedly positioned input measuring roller 6b, configured to determine the radial runout of the roller 6b and compensate for possible non-circular movement using measurement techniques. This allows for verification of the measurement accuracy of the determined sliver weight deviation. The sensor 27 can be configured, for example, as a movable coil or a piezoelectric element. The first upper roller 8 is driven by friction by the pressure of the cylinders 11a and 11b on the rolling bearings 8.4 and 8.5, pressed against the first lower roller 7 by the roller cover 8.1. Separating the drive unit into an upper drive housing 4a (with the first pair of draft rollers 7 and 8) and a lower drive housing 4b (with the two pairs of draft rollers 9 and 10) enables adjustability of the clamping line distances L1 and L2. This allows for independent control of the draft roller pairs in terms of both the rotational speed of the lower rollers 7 and 9 and the load pressure of the upper rollers 8 and 10. Furthermore, the driven measuring rollers 6b and 15b are decoupled from each other in terms of drive technology, eliminating the need for cross belts.

[0041] The lower drive housing 4b also has its own second drive 30, which simultaneously drives the sliver can turntable 41. A first belt 31 drives the second lower roller 9 and the fixed output measuring roller 15a. A second belt 32, driven by the fixed output measuring roller 15a, drives the adjustable output measuring roller 15b. The second belt 32 is deflected by a steering roller 34, causing the two output measuring rollers 15a and 15b to be driven in opposite directions, passing the fiber sliver FB between them and transporting it into the coil tube 40. A tensioning element 35 ensures the necessary belt tension. A third belt 33, driven by the second drive 30, rotates the sliver can turntable 41. Drives 21 and 30 can be configured as servo drives, thus eliminating the need to change gears when changing the draft zone width or draft ratio according to the fiber to be processed.

[0042] List of reference numerals

[0043] 1. Drafting mechanism

[0044] 2. Cover

[0045] 2a, 2b wings

[0046] 3. Flip-top

[0047] 3a Opening

[0048] 4a, 4b Driver housings

[0049] 5 First Funnel

[0050] 6, 6a, 6b Input measuring roller pairs

[0051] 7 First lower roller

[0052] 8 First upper roller

[0053] 9 Second lower roller

[0054] 10 Second upper roller

[0055] 11a First Cylinder Block

[0056] 12a Second Cylinder Block

[0057] 13 Compression bars

[0058] 14 Second Funnel

[0059] 15a and 15b output measuring roller pairs

[0060] 16. Peeler

[0061] 17 Sensors

[0062] 21 First Driver

[0063] 23 Adjustment elements

[0064] 24 Guide Board

[0065] 26 First Belt

[0066] 27 Sensors

[0067] 28 Second belt

[0068] 29. Steering rollers

[0069] 30 Second drive

[0070] 31 First Belt

[0071] 32 Second belt

[0072] 33 Third Belt

[0073] 34 Steering Rollers

[0074] 35 tensioning elements

[0075] 36b lever

[0076] 37 tubes

[0077] 40 coils of tubing

[0078] 41-slot rotary table

[0079] A coiler

[0080] FB fiber strips

[0081] K-type carding machine

[0082] R steering roller

[0083] S-type storage tank

[0084] V offset

[0085] W-type skein changer

[0086] x, y, z directions.

Claims

1. Method for adjusting the grammage of a fibre band (FB) in an integrated drafting mechanism (1) of a carding machine (K) having an input measuring roller pair (6a, 6b) located before a main drafting zone of the drafting mechanism and having an output measuring roller pair (15a, 15b) located after the main drafting zone, wherein, The grammage of the fibre band (FB) at the input measuring roller pair (6a, 6b) forms a given parameter, and the draft ratio of the drafting mechanism forms a manipulation parameter, wherein a change in the grammage of the fibre band (FB) at the input measuring roller pair (6a, 6b) results in a change in the manipulation parameter in the controller of the card (K), and the amount of change in the manipulation parameter is stored in the controller of the card (K) by a graph or a curve, which is formed by at least two parameters.

2. The method of claim 1, wherein, A first parameter of the graph or curve is formed by the adjusted draft ratio of the drafting mechanism (1) at a given parameter, and at least one second parameter is formed by the changed draft ratio at an increased or decreased grammage of the fibre band (FB) at the input measuring roller pair (6a, 6b).

3. The method of claim 2, wherein, A third parameter is formed by the changed draft ratio at a changed grammage of the fibre band (FB) at the input measuring roller pair (6a, 6b), which is different from the grammage of the fibre band (FB) at the second parameter.

4. The method of claim 1, wherein, The change in the manipulation parameter is made directly in the event of a deviation from the given parameter, or after a preset time, which is adjustable in the controller of the card (K) depending on the supply speed.

5. The method of claim 2, wherein, The grammage of the fibre band (FB) at the input measuring roller pair (6a, 6b) can differ by ±50% from the preset grammage of the fibre band (FB) at the input measuring roller pair (6a, 6b) in order to determine the graph or curve, preferably by ±30%.

6. Drafting mechanism for drafting individual combed sliver (FB), wherein The fibre band is produced in a card (K) and enters the drafting mechanism (1) without interruption, which has one input measuring roller pair (6a, 6b) in the material flow direction, which has a sensor for determining the grammage of the fibre band (FB), only one 2 over 2 under drafting mechanism or one 2 over 3 under drafting mechanism downstream in the material flow direction, which has one main drafting zone and one output measuring roller pair (15a, 15b) arranged downstream in the material flow direction, which has a sensor for determining the grammage of the fibre band (FB), wherein the drafting mechanism (1) is controlled by the controller of the card (K) and is configured to run the method according to any one of claims 1 to 5.

7. Drafting mechanism according to claim 6, characterized in that The drafting mechanism has a first drafting roller pair (7, 8) and a second drafting roller pair (9, 10), wherein each of the drafting roller pairs (7, 8; 9, 10) is assigned its own controllable drive for adjusting the draft ratio.

8. Drafting mechanism according to claim 6, characterized in that The output measuring roller pair (15a, 15b) is configured to transport the fibre band into a can changer.

9. The drafting mechanism of claim 6 wherein, The drafting mechanism does not have a pre-drafting zone.

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