WO1993009280A1 - Method and device for determining the diameter of a bobbin at a spinning point on a spinning machine - Google Patents

Abstract

The invention concerns a method for determining the diameter of a bobbin at a spinning point on a spinning machine processing slivers, plus a device for carrying out this method. The aim is to avoid the disadvantages described in the application and to determine the diameter of each bobbin simply and without any direct contact with the bobbin.

Description

 Method and device for determining the diameter of a bobbin at a spinning position of a spinning machine

The present invention relates to a method for ascertaining the diameter of a bobbin at a spinning station of a spinning machine, in which a sliver of known strength is fed to the spinning station at a certain speed, spun there into a thread and then from there with one to Strip feed speed is deducted in a defined ratio of the take-off speed and is wound up on the spool with a matching winding speed, as well as a device for carrying out this method.

In order to determine the diameter of the coil, it is known to implement a variable stop with respect to the coil surface. The variable stop is a mechanical measure to determine the changing coil diameter at the desired times. In this context, the use of mechanical sensors that continuously or discontinuously contact the coil surface is common.

As practice shows, the prerequisite for accurate functioning is that hard-wound bobbins are always produced, which is a limitation. In the case of softly wound coils, the solution mentioned has the disadvantage that by pressing in the variable stop on the coil

REPLACEMENT LEAF Surface the signal to be formed for the coil diameter is falsified. This fact leads to inaccuracies which reduce the probability of success for detecting a thread end after thread break in the first attempt or otherwise initiate the bobbin change inaccurately. The mechanical scanning of the coil diameter by means of a button (DE-OS 38 27 345) does not eliminate the disadvantages shown in the prior art.

With the use of non-contact sensors, a second way of detecting the diameter of the bobbin is recognizable. An optical sensor continuously determines the changing diameter of the coil without having to mechanically touch the surface. An optical scanning (DE-OS 36 17 151, Fig. 3) has the disadvantage that the optics on the textile machine can become dirty with dust, fibers and other particles, which has the consequence that the signal obtained is falsified.

A third possibility (US Pat. No. 3,877,309) according to the prior art consists in detecting the speed of the take-off roller or winding roller, on the basis of which the yarn length and thus the diameter of the package are determined.

This solution has not been used in particular for the positioning of a thread take-up device with respect to a bobbin surface, since practical influencing factors remain unconsidered, which falsify the constant gap formation between the surface of the package and the thread take-up device. However, these influencing factors also lead to inaccuracies in determining the point in time for initiating the coil change.

Such influencing factors are differently hard, possibly run-in pressure rollers, which leads to different slip on the take-off rollers;

unevenly worn driving rubbers on the friction rollers, which results in a different winding tension.

As a result of the variety of spinnable materials and different manufacturing parameters (yarn strength, winding tension), different yarn thicknesses and winding hardness are common, which make a sensorless determination of the bobbin diameter as a reference variable for the control appear inaccurate than when using diameter-sensing sen ¬ sensors.

It is an object of the present invention to provide a method and a device which avoid these disadvantages and make it possible to determine the respective diameter of the coil in a simple manner without directly scanning the coil.

This object is achieved according to the invention by empirically determining the yarn thickness corresponding to a specific bobbin diameter under predetermined conditions (yarn strength, winding tension), that taking into account possible production interruptions at this spinning station, the yarn length produced is measured such that the product of the tape thickness with the quotient of the tape feed speed and the thread take-off speed, the yarn thickness is determined, that from the quotient of the wind-up speed and the take-off speed, a parameter for the winding hardness of the bobbin is determined, that the determined yarn thickness and the winding tension corresponding to the determined winding hardness with the yarn thickness and the winding tension, that of the empirical yarn length determination for the specific bobbin diameter have been compared, and any deviation that may arise is used as a correction factor for the yarn length when determining the actual bobbin diameter. The empirical determination of the yarn length serves to create a reference value. Can the length of the yarn be measured during the production of a bobbin by direct scanning of the yarn fed to the bobbin? Of course, even after the production of a bobbin, ie after it has reached its desired size, the yarn can be unwound from this bobbin and measured in a suitable and customary manner.

Now it is important to produce the same length of yarn during production, since this - if not any influences which lead to falsifications - have to be taken into account - produces the same bobbin size. It is important to ensure that any production interruptions such as B. Fix thread breakage, take into account when determining the yarn length. For this reason, the yarn length produced is measured, which is done, for example, by measuring the revolutions of a take-off roller - taking into account its diameter - and - taking into account such production interruptions - the actual yarn length generated is calculated therefrom. Since the bobbin diameter depends on the thread thickness, this is determined from the diameter of the spun fiber ribbon and the distortion, ie the quotient of the ribbon feed speed and the thread take-off speed. The bobbin diameter also depends on how tightly the bobbin is wound, ie on the winding tension, which is why this is also determined from the quotient of the winding speed and the take-off speed. Now the yarn thickness specified as a reference value and the winding tension specified as a reference value are measured with the measured actual values compared values.

From the deviations that result, a correction value is then formed, which is taken into account in the determination of the actual bobbin diameter and leads to an increase or decrease in the yarn length - in comparison to the reference yarn length - which leads to the corresponds to certain coil diameter. It goes without saying that the computer carrying out the corresponding correction was programmed beforehand, when the reference values were entered, so that the corrections lead to the correct end values. The correction values are to be determined empirically once and can then be used in the same way for all machines be entered.

In order to rule out inaccuracies, in particular in the production of conical coils, it is further expediently provided that a cone-shaped coil is based on a coil diameter based on a specific surface line as a reference.

It may be that after a long period of time the pressure roller of the pair of draw rollers runs in. The same applies to the winding roller for driving the bobbin to an even greater extent.

For this reason, it can be provided in a further advantageous embodiment of the method according to the invention that the actual yarn length for a specific bobbin diameter is checked at predetermined time intervals and, if the actual yarn length deviates from the theoretical yarn length to be expected taking into account the correction factor, the correction factor is corrected. In this way, the wear that has occurred in the meantime is taken into account from time to time, so that the coil size, despite wear, affects the coil diameter Drive elements can be kept constant within relatively small tolerances.

The measurements of the yarn length can in principle be carried out with any bobbin diameters, which is also particularly useful when determining the reference values. When checking the coil diameter later, however, it is generally sufficient if the desired diameter of the full coil is selected as the specific coil diameter.

Since the twist of the yarn causes the yarn to become harder or softer, when the twist is mechanically given the twist - which e.g. in the case of rotor or frit spinning machines - in a further advantageous embodiment of the method according to the invention it is provided that the yarn rotation is taken into account, for which purpose the rotation of the yarn per unit length is determined from the quotient of the speed of the spinning element and the take-off speed and the Ab ¬ deviation from a predetermined reference value is taken into account as a correction factor when determining the actual coil diameter. The predefined reference value has already been fed during the programming of the computer, so that a comparison with this known reference value is now possible. The measurement of the yarn twist can be carried out in addition to the determination of the yarn thickness, since - as said - the actual yarn thickness depends not insignificantly on the twist contained in the yarn.

In the case of spinning rotors, the speed of the spinning element is exactly the same as the number of twists generated in the thread per unit of time. In the case of friction spinning elements, however, the diameter of which is a multiple of the diameter of a thread and whose rotation is achieved by rolling the thread on the circumferential surface of at least one friction spinning element. folt, on the other hand - based on the speed of the frit spinning element - a much higher speed is generated in the thread, which must be taken into account when determining the yarn twist per unit length. According to the invention, in devices in which the rotation is transmitted from the circumferential surface of the rotating spinning element to a thread which is rolling thereon and is being formed, provision is made for the rotation transmission ratio between the spinning element to be determined for the length of the thread per unit length and thread is taken into account.

In spinning processes in which the yarn twist is effected pneumatically, the yarn twist and thus the hardness of the yarn depends on the strength of the excess pressure which is brought to bear on the thread. This also applies to a pneumatic open-end spinning process, in which the individual fibers are integrated in a rotating yarn end, as well as to a pneumatic false-wire spinning process, in which a fiber band is drawn into a fiber band, rotated incorrectly and by spreading and re-integrated fibers ends in the wrongly rotated position.

For pneumatic spinning processes it is therefore provided in a further advantageous embodiment of the subject matter of the invention that the overpressure which causes the yarn rotation and acts in the spinning element is measured and the deviation from a predetermined reference value is taken into account as a correction factor in determining the actual bobbin diameter.

However, the overpressure does not have a directly proportional effect on the yarn twist and thus on the hardness and thickness of the yarn. The size of the supply bore for the compressed air supplied to the spinning element, the position of these supply bores with respect to the central passage in the spinning element and their Inclination with respect to the longitudinal axis of the spinning element cause the overpressure in the spinning element to have a greater or lesser effect, so that the overpressure more or less influences the yarn thickness accordingly. This different influence intensity of the overpressure due to different geometric modifications of the spinning element is taken into account according to the invention in that when the spinning element is replaced by one having a different geometry, the geometric deviations from a given geometry of the spinning element are taken into account as a correction factor in determining the actual spool diameter ¬ is viewed. The size of the correction factor is determined empirically beforehand and can then be input directly without further tests if necessary, by providing appropriate markings for the correction factor at the entry point or by taking the corresponding value from a table and as a numerical value is entered.

Another factor that can affect the bobbin diameter is the properties of the fiber material that is spun. Natural fibers are usually much more elastic and fuller than synthetic fibers. Here, too, a reference value is formed when feeding the computer. Furthermore, according to the invention, it will later be provided during production that fiber material properties which have an effect in the bobbin diameter are taken into account as a correction factor for determining the actual bobbin diameter.

Determining the current coil diameter is important for a wide variety of purposes. Advantageously, a signal for initiating a coil change is triggered, for example, as a function of reaching a predetermined coil diameter, taking the correction factors into account. On the other hand, determining the bobbin diameter is also very important in connection with the removal of a broken thread. According to the invention, in connection with the removal of a thread break, the determined bobbin diameter is fed to the drive of a thread take-up device as a signal parameter for determining an actuating value, and the thread take-up device is brought into a defined distance from the outer surface of the bobbin under construction.

The thread take-up device and its drive can also show signs of wear which have an effect on the individual spinning positions as adjustment inaccuracies and thus also impair the thread take-up safety. According to the invention, it is therefore expediently provided that such a play occurring at the individual spinning positions and acting at a distance from the thread take-up device to the lateral surface of the bobbin is taken into account as a correction factor.

Such play can change over time as a result of wear and thus also lead to a change in the delivery accuracy of the thread take-up device to the bobbin. To compensate for such changes in play, it is provided in a further advantageous development of the method according to the invention that the play occurring at the individual spinning positions, which acts at a distance from the thread take-up device to the outer surface, is checked at predetermined time intervals and, when this play changes, corresponds to the play ¬ correction factor be corrected.

To carry out the method according to the invention, in order to determine the current spool diameter of the tape feed device, the take-off device and the winding device, according to the invention a speed pick-up device which determines their speed of rotation is associated with the a common control device is connected in terms of control, into which the yarn length corresponding to a certain bobbin diameter can be entered, which can be corrected in the form of correction factors which are calculated on the basis of the determined speeds of the tape feed device, take-off device and on device.

In order to be able to take the yarn rotation into account when determining the respective bobbin diameter, in a further advantageous embodiment of the device according to the invention, when the spinning element rotates for the manufacture of the yarn, a measuring element measuring its speed is assigned to the spinning element or its drive, or zu¬ adjustable, which is connected in terms of control to the control device for generating a correction factor.

It is not a requirement for the present invention that the spinning element rotates. The invention can also be used when the spinning element is of a non-rotating nature and in it an air vortex rotates for yarn production, which is kept rotating by a compressed air supply with a tangential component. This can be an open-end spinning element or just a spinning element in which a false twist is given to a fiber ribbon to form a thread. According to the invention, in such a case it is provided that the control element has at least one compressed air supply opening opening laterally into a thread formation zone from which the thread forming is drawn off and a compressed air line ending in this at least one compressed air supply opening or a compressed air supply opening Generating compressed air source is assigned a signal transmitter determining the level of the excess pressure, which is connected in terms of control to the control device for generating a correction factor. The control device is preferably connected in terms of control to a bobbin changing device, so that when a predetermined bobbin size is reached, an exchange of a full bobbin for an empty tube can be initiated.

Furthermore, it is advantageous if the control device is connected in terms of control to a drive for a thread take-up device, by means of which it can be brought into a defined distance from the respective lateral surface of the bobbin under construction. Since a wide variety of correction values can be entered into the control device - in addition to the reference values - the thread take-up device can always be brought into an optimal position in relation to the bobbin under construction in order to receive the thread end required for re-spinning.

Since not all correction factors can be measured automatically, but in some cases have to be determined empirically, e.g. B. changing tolerances, the invention expediently provides that the control device is assigned an input device for the manual input of correction factors. In this case, the input device is advantageously divided into a plurality of partial input devices, one of which is for the input of fiber material properties which have an effect on the bobbin diameter and the other is for the input of a game which has an effect on the delivery of the thread take-up device to the bobbin at the respective spinning station serves.

In order not to have to assign individual input devices to each spinning station, it is provided in a further advantageous embodiment of the subject matter of the invention that the control device has a separate memory for each spinning station, to which the input device can optionally be assigned. “Correction factor” in the sense of the present invention is understood to mean any value that changes the values entered as the basic setting in the control device. It is irrelevant whether the theoretical yarn length, any play anywhere, wear in the transport and transmission elements and the like. Like. takes into account.

The bobbin diameter is required as a signal parameter for the control both of the bobbin change at the right time and for the control of a thread take-up device. The technical facts are described below until the coil diameter is determined, i. H. until a corresponding signal parameter is obtained, which is ultimately used as an input variable for controlling the above-mentioned processes.

As already stated above, the method according to the invention and the device according to the present invention enable a precise and precise determination of the current coil diameter in a simple and safe manner without contact and in adaptation to a wide variety of variables including different wear, which for different tasks during of the spinning process is essential. So the spool change can be carried out exactly in time. In addition, even in the case of conical bobbins, the length of thread required for piecing can be measured more precisely when the bobbin size is known than without knowledge. In addition, for the precise thread take-up from the bobbin, it is essential that the bobbin size is known, so that the thread take-up nozzle is set precisely in relation to the bobbin for the take-up, so that the thread take-up nozzle is as close as possible to the spool without damage To bring the coil surface. The inventive solution can be used both in the case of open-end spinning devices with mechanical and also in the case of fiber spinning devices with pneumatic swirl division. It is not even necessary for the spinning device to be one that works according to the open-end spinning principle, such as rotor spinning, friction spinning or electrostatic spinning, but the invention can also be used for false wire spinning with pneumatic twisting bring to use.

The subject matter of the invention can be implemented economically, since as a rule all the driven elements have a central drive to which the rotary knives can be assigned. As a result, the subject of the invention can also be retrofitted inexpensively to existing machines with a large number of similar workplaces.

Embodiments of the invention are shown in the drawing. Show it:

Figure 1: Sequence of signal acquisition and processing according to the invention for determining the coil diameter in rotor spinning or in spinning with pneumatic twist distribution;

FIG. 2 shows a schematic cross section through a spinning station of a rotor spinning machine designed and constructed in accordance with the invention;

3 shows a schematic cross section with a partial top view through a spinning station of a false-wire spinning machine designed according to the invention. Since the rotor spinning machine in particular has found its way into practice, a first exemplary embodiment of the object of the invention will be explained with the aid of an open-end spinning machine designed as a rotor spinning machine.

FIG. 2 shows a cross section through a work or spinning position of such a rotor spinning machine with only the essential elements that are absolutely necessary for understanding the invention? on the other hand, for the sake of clarity of the drawing, the other elements required for spinning or piecing have been omitted.

The spinning device 1 of the rotor spinning machine has a feed device 2, a dissolving device 3 and a spinning element designed as a spinning rotor 4. Downstream of the spinning device 1 are a take-off device 5 and a winding device 6.

The feed device 2 has a driven feed roller 20 and a feed trough 21 which cooperates with it. A sliver B stored in a can 22 is fed to it. The feed roller 20, which usually extends over a large number of spinning positions, is located at a suitable location, e.g. in the drive end frame of the machine, a sensor 23 is assigned, which detects the speeds of the feed roller 20.

The opening device 3 has a opening roller 30, which is arranged in a housing 31, from which a fiber feed channel 40 extends into the spinning rotor 4, around the fibers F that emerge from the leading end of the rotating opening roller 30 through the feed device 2 fed sliver B are combed out, fed to the spinning rotor 4, where they are tied into the end of a thread G. the .

The thread G leaves the spinning rotor 4 arranged in a housing (not shown) through a thread draw-off tube 41, for which purpose it is continuously pulled out of the spinning rotor 4 by the draw-off device 5. The take-off device 5 consists in the usual way of a driven take-off roller 50, which extends over a large number of spinning stations, and one pressure roller 51 per spinning station.

The thread G is fed through the take-off device 5 to the winding device 6, which has a winding roller 60 which extends over a plurality of spinning positions and on which the forming bobbin 61, which is held rotatably between two swivel arms 62, rests for each spinning position. The winding device 6 has a traversing thread guide 63 for the chan- ning laying of the thread G.

Like the feed device 2, the spinning rotor 4, the take-off device 5 and the winding device 6 are each assigned a sensor 42, 52 or 64. The sensor 42 scans the spinning rotor 4 itself or its shaft 43 or its drive (e.g. support disks - not shown - which rotate in a fixed speed ratio to the spinning rotor 4). The sensors 52 and 64 sense the draw-off roller 50 and winding roller 60, respectively, which extend over a plurality of spinning positions and are located at a suitable location, e.g. as well as the sensor 23, arranged in the drive end frame of the machine.

The sensors 23, 42, 52 and 64 are connected via lines 24, 44, 52 and 65 to a control device 7 which carries out various processes such as e.g. control the replacement of a full bobbin 61 for an empty tube or a piecing event after a machine stoppage or a thread break.

REPLACEMENT T An input device 70 with several setting devices 71, 72 and 73 is connected to the control device 7 via a line 74, the meaning of which will be described in detail below.

On the OE spinning machine described, four different speeds are thus detected using conventional sensors 22, 42, 52 and 64. These are:

the speed of the feed roller 20 (sensor 23) _?

the rotor speed (sensor 42);

the speed of the take-off roller 50 (sensor 52);

the speed of the winding roller 60 (sensor 64).

Furthermore, the thickness of the incoming sliver B is determined by a sensor 25 for thickness measurement. The sensor 25 is connected to the control device 7 via a line 26.

Various constants that influence the coil size are manually entered via a keyboard or by means of rotatable adjusting knobs (input devices 71 to 74) of the input device 70. These include e.g. Material constants which influence the thread size. These material constants result from the diversity of the material to be processed, e.g. B. elasticity and strength of the cotton or plastic fibers. In connection with the signal detection, the signals coming in via sensors 23, 25, 42, 52 and 64 are detected and fed to further processing.

There are three basic processing levels which, in their combination, lead to the determination of the yarn length. In a first level, the signal detection ΞE2 detects the number of the fiber sliver B fed (sensor 25), the speed of the feed roll 20 (sensor 23) and the speed of the take-off roll 50 (sensor 52).

The yarn strength can be determined as the product P from the number of the fiber sliver B and the quotient of the feed roller speed to the speed of the take-off roller 50. The properties of different materials influencing the yarn strength (such as fiber strength, inter alia) are known material parameters, which are also used as a signal parameter be taken into account when forming the signal for the thread strength. These material parameters are entered manually via a keyboard or a different sorting device 71 of the input device 70, for which purpose the memory has a separate memory for each spinning station, to which the input device 70 can be optionally assigned. For this purpose, a numerical keyboard is provided, for example, by means of which the desired spinning position can be set.

The starting point for the determination of the voltage, which is a measure of the winding hardness of the coil 61, are the rotational speed for the take-off roller 50 (sensor 52) and the rotational speed of the winding roller 60 (sensor 64). The signals obtained via the signal detection SEI are processed into a quotient Q1 from the speed of the winding roller 60 to the speed of the take-off roller 50. The signal parameter SKI for this quotient forms the wind-up voltage.

The starting point for determining the yarn twist is the detection of the rotor speed (sensor 42) and the speed of the take-off roller 50 (sensor 52) in the signal detection SE3. A signal parameter is determined by forming the quotient Q2 from the rotor speed to the speed of the take-off roller 50 SK3 determined, which represents the yarn twist.

When the OE spinning machine is started up for the first time, the signal parameters for yarn size SK2, winding tension SKI and yarn twist SK3 are determined. In order to further minimize the influencing factors on these signals, corresponding correction values are determined. The correction values result from reference methods, in that the yarn strength, winding tension and yarn twist determined at any later times are compared with the respective quantities which were the basis for the first start-up for the specific bobbin diameter, and deviations as correction factors for the yarn length be used as a basis for determining the actual coil diameter. The correction values of the winding tension KF1, the yarn strength KF2 and the yarn twist KF3 obtained by reference methods are linked to determine the yarn length SK-GL. Taking into account possible production interruptions at a spinning station, the yarn length generated is to be determined.

The signal parameter SK-GL for the yarn length is checked in the reference method with regard to the formation of a correction factor. When a correction factor for the yarn length KF-GL is formed, this is taken into account in the subsequent determination of the bobbin diameter.

The bobbin diameter which can be corrected in this way is used as the signal parameter SK-SD for the control S of the bobbin change in accordance with the point in time or the control S of a thread take-up device 66 (FIG. 2) with respect to the bobbin surface, the bobbin target size for the bobbin change by the Setting device 73 is entered via a line 73.

Such a thread take-up device 66 is shown in broken lines in FIG. 2 and is usually used as a suction nozzle formed, which is arranged on a maintenance device which is movable along the spinning machine. The suction nozzle is pivotally mounted and can be pivoted from a rest position, in which it is pivoted away from the coil 61, into a working position, in which its mouth is arranged at a predetermined distance from the circumferential surface of the coil 61, by a thread break while simultaneously turning back the spool 61 to suck in the end of the thread on the spool 61. If the distance is too large, the suction force acting on the bobbin surface is too weak to take up the thread G; if, on the other hand, the distance is too short, the mouth of the suction nozzle at least partially abuts the layers of the spool 61, so that there is a risk that these layers or the wound thread G will be damaged or become damaged. The suction nozzle of the thread take-up device 66 is connected via a coupling housing 67 to a drive 68 which can bring the suction nozzle into a defined position with respect to the bobbin 61. For example, the drive 68 is assigned a stop and a slip clutch (not shown), the stop being set by the control device 7 via a line 69 in accordance with the current coil size. For this purpose, the suction nozzle is also movably mounted at its end facing the suction air source via a pivotable intermediate tube piece.

If a game is determined at a constant distance during the positioning of the thread take-up device 66 by means of checks carried out from time to time against the bobbin surface, this game can be compared directly in the distance position by manually entering a correction value via the keyboard (adjusting device 72, line 74a) the control can be corrected.

The method and / or the device can be used in a variety of ways within the scope of the present invention. be changed, for example by exchanging individual characteristics with equivalents or with other combinations. It is thus possible, for example, to distribute the adjusting device 71, 72 and 73 to different input devices 70 which are arranged at different locations and / or which are different from one another. The input devices can also be designed for the input of digitally selectable numbers or as rotary knobs for the input of analog values.

As already stated above, the invention is not limited to spinning machines with mechanical twist distribution. Rather, it can be used on all spinning machines on which a sliver B is spun into a thread G. Such a spinning machine is e.g. also a wrapping spinning machine, on which a core yarn is produced, around which a wrapping yarn is looped. It goes without saying that the strength of the wrapping yarn, the number of wraps per unit length and the tension with which the wrapping thread is wrapped around the core yarn must be taken into account. Appropriate sensors and / or setting devices must be provided for this.

If the spinning element, for example a spinning rotor 4, receives rotation, which it then passes on to the thread G being formed, the yarn twist can be determined very easily directly from the speed of the spinning element. In the case of a spinning rotor 4, the number of rotations is predetermined directly by the rotor speed. In the case of a friction spinning element, the ratio between the diameter of the driven friction spinning element and the thread G must be taken into account when calculating the yarn twist. In such a case, the relevant diameter ratio must also be taken into account when calculating the quotient of the speed of the spinning element and the take-off speed. With others Expressed in words, this means that when the twist is transmitted from the circumference of the spinning element to the thread rolling on it, which is being formed, the twist transmission ratio must be taken into account for determining the twist per unit length.

As already mentioned above, the method can also be used in spinning machines in which the thread is twisted in a pneumatic way. Such a spinning device is shown in FIG. 3. In this case, a drafting device serves as feed device 8, which, with its pairs of rollers 80, 81 and 82, warps the supplied sliver B into a sliver which is spun into a thread G in the spinning element 9.

In the exemplary embodiment shown, the spinning element 9 consists of a first nozzle, an injector nozzle 90, and a swirl nozzle 92 arranged downstream of it, leaving a gap 91. The injector nozzle 90 and the swirl nozzle 92 each have compressed air supply openings 900 and 920, which emanate from an annular channel 901 or 921 which surrounds the injector nozzle 90 or the swirl nozzle 92 and which essentially tangentially terminate with axial component in the axial bores 902 or 922 of the injector nozzle 90 or the swirl nozzle 92. The two ring channels 901 and 921 are above two.

Lines 903 and 923 with a common line 93 and via this to a common pressure source 94 in connection. A manometer 95 is connected to line 93 and is connected in a control manner to control device 7 via line 96.

Two sensors 83 and 85 are also connected to the control device 7 via lines 84 and 86, each of which has a roller at the outlet or at the inlet of the stretching device.

REPLACEMENT LEAF factory 8 located roller pair 82 or 80. Furthermore, sensors 25, 52 and 64 are connected via lines 26, 53 and 65, which - as explained using the example in FIG. 2 - scan the fiber sliver B, the take-off roller 50 and the winding roller 60.

An input device 70 is also in control-related connection with the control device 7 via lines 74, 74a, 74b, 74c, which has an adjusting device 71 (line 74b) for adjusting the processed material, an adjusting device 72 (line 74a) for adjusting an Correction factor for the wear affecting the mechanics of the thread take-up device 66 (see FIG. 2), an adjusting device 73 (line 74) for setting the desired nominal bobbin diameter for the full bobbin 61 and an adjusting device 76 (line 74c) for setting a correction factor to take into account the geometry of the spinning element 9 consisting of the injector nozzle 90 and the swirl nozzle 92.

The manometer 92 measures the overpressure which prevails in the line 93 and is therefore present in the compressed air supply opening 900 or 920, which opens laterally into the thread formation zone. In the device described, the thread formation zone is formed by the two axial bores 902 and 922 of the injector nozzle 90 and the swirl nozzle 92. The manometer 95 thus detects the excess pressure applied to the spinning element 9 and emits a corresponding signal to the control device 7. As shown, the signal transmitter (manometer 95), which determines the level of the effective overpressure, can be assigned directly to the line 93 or the overpressure source 94.

To determine the actual coil diameter, the control device 7 is continuously - apart from the signals coming from the sensors 25, 85, 83, 52 and 64 - measured by the nometer 95 signals are fed, which are compared with a value registered in the control device 7 as a reference value. If the signal from the manometer 95 deviates from the target value, a corresponding correction factor is formed to correct the value for the coil diameter.

The distortion of the fiber sliver B is calculated from the signals coming from the sensors 85 and 83 and can be corrected by the signal coming from the sensor 52.

The reference values, for the setting of which only the setting device 73 is shown in the input device 70, are all set in the input device 70 by means of additional setting devices, the input device 70 or part of the control device 7 integrated therein can be.

If the spinning element 9 is replaced - either completely or only the injector nozzle 90 or the swirl nozzle 92 - against a spinning element of a different geometry with regard to dimensioning and / or arrangement or orientation of the compressed air supply openings 900 and / or 920, then of course also changes the effect of the compressed air on the thread G, and there is a different rotation. This must be taken into account when calculating the bobbin size, since this changes the yarn hardness and thus the yarn cross-section.

This influence is thus determined by experiments for each spinning element 9 in question and recorded in the form of a correction factor which can either be stored in the control device 7 for later retrieval by means of the adjusting device 76 or entered in a table, from which it can be removed for input into the input device 80 (adjusting device 76) if necessary. In the case of conical coils 61, the value of a specific surface line is used as the reference value. In principle, any surface line can be used here, but it has proven to be expedient to select the diameter of the length range on which the drive takes place as a reference in the case of coils 61 which are driven over their outer circumference.

Since the rollers conveying the fiber material or the rollers driving them are subject to wear, deviations occur over time between the desired target value for the coil diameter and the actual coil diameter. In order to keep these deviations within acceptable limits, it is checked from time to time, preferably at predetermined time intervals, whether deviations occur and how large they are. If necessary, a correction factor is to be entered by means of a setting device (not shown) of the input device 70.

In principle, any desired coil diameter is suitable for determining setpoints. However, since the scatter is smaller when a longer yarn length is selected, it is particularly expedient to use the full bobbin 61 to determine the bobbin size to be assigned to a specific yarn length.

Claims

P a t e n t a n s r u c h e Method for determining the diameter of a bobbin at a spinning station of a spinning machine, in which a sliver of known strength is fed to the spinning station at a certain speed, spun there into a thread and then from there at a defined ratio to the belt feed speed the take-off speed is drawn off and wound onto the spool at a winding speed which is matched to this, characterized in that under given conditions (yarn strength, winding tension), the yarn length corresponding to a certain bobbin diameter is determined empirically, taking into account possible production interruptions at this spinning station, the yarn length produced is measured, the yarn thickness is determined from the product of the strip thickness using the quotient of the strip feed speed and thread take-off speed, - that from the quotient of the wind-up speed and the take-off speed a parameter for wind-up wind voltage is determined - That the determined yarn thickness and the ascertained winding tension are subsequently compared with the yarn thickness and the winding tension which have been based on the empirical yarn length determination for the specific bobbin diameter, and a resultant deviation as a correction factor for the yarn length when determining the actual Coil diameter is used as a basis. 2. The method according to claim 1, characterized in that in the case of conical coils, a coil diameter based on a specific surface line is used as a reference. 3. The method according to claim 1 or 2, characterized gekennzeich¬ net that the actual yarn length is checked for a specific bobbin diameter at predetermined time intervals and if the actual yarn length deviates from the theoretical yarn length to be expected taking into account the correction factor, the correction factor is corrected . 4. The method according to one or more of claims 1 to 3, characterized in that the desired diameter of the fully wound coil is selected as the specific coil diameter. 5. The method according to one or more of claims 1 to 4, characterized in that the rotation of the yarn per unit length is determined from the quotient of the speed of the spinning element and the take-off speed and the deviation from a predetermined reference value as a correction factor in the determination of the actual Coil diameter is taken into account. 6. The method according to claim 5, characterized in that in the transmission of rotation from the circumference of the rotating spinning element to the rolling thereon, in the formation located thread for determining the rotation of the thread per unit length, the rotation transmission ratio between the spinning element and the thread is taken into account becomes. 7. The method according to one or more of claims 1 to 4, in which the yarn rotation is generated pneumatically, characterized in that the yarn rotation effecting in the spinning element is measured and the deviation from a predetermined reference value is used as a correction factor in determining the actual coil diameter is taken into account. 8. The method according to claim 7, characterized in that when replacing the spinning element with one having a different geometry, the geometric deviation from a given geometry of the spinning element is taken into account as a correction factor when determining the actual spool diameter. 9. The method according to one or more of claims 1 to 8, characterized in that fiber material properties which have an effect in the bobbin diameter are taken into account as a correction factor for determining the actual bobbin diameter. 10. The method according to one or more of claims 1 to 9, characterized in that, depending on the achievement of a predetermined coil diameter determined taking into account the correction factors, a Si signal to initiate a coil change is triggered. 11. The method according to one or more of claims 1 to 10, characterized in that, to eliminate a thread break, the determined bobbin diameter is supplied to the drive of a thread take-up device as a signal parameter for determining an actuating value and the thread take-up device is at a defined distance from the jacket surface are brought to the coil under construction. 12. The method according to claim 11, characterized in that occurring at the individual spinning positions, which in the distance of the thread take-up device to the outer surface of the bobbin, play is taken into account as a correction factor. 13. The method according to claim 11 or 12, characterized gekennzeich¬ net that the occurring at the individual spinning positions, acting in the distance of the thread take-up device to the mantle surface game is checked at predetermined time intervals and the corresponding correction factor is corrected when this game changes. 14. Device for determining the diameter of a bobbin at a spinning station of a spinning machine, with one spinning element each, one controllable sliver feed device for feeding a sliver, one controllable take-off device and one controllable winding device per spinning station, for carrying out the method according to one or more of claims 1 to 13, characterized in that the tape feed device (2, 8), the take-off device (5) and the winding device (6) each have a speed pick-up device (23, 85, 83, 52) which determines their speed of rotation , 64) assigned, which are connected in terms of control to a common control device (7), into which the yarn length corresponding to a certain bobbin diameter can be entered, which in the form of correction factors, the take-off device based on the determined speeds of the tape feed device (2,8) (5) and updraft device (6) can be calculated, can be corrected. 15. The apparatus according to claim 14, characterized in that the spinning element (4, 3) or its drive a des¬ sen speed measuring element (42) is assigned or deliverable, which is connected to the control device (7) for generating a correction factor in terms of control . 16. The apparatus according to claim 14, characterized in that the spinning element (9) has at least one compressed air supply opening (900, 920) opening laterally into a thread forming zone from which the thread (G) being formed is drawn off axially and to a compressed air line (93) terminating in this at least one compressed air supply opening (900, 920) or to a compressed air source (94) producing the compressed air, a signal transmitter (95) determining the level of the excess pressure is assigned, which is connected to the control device (7) is connected in terms of tax to generate a correction factor. 17. The device according to one or more of claims 14 to 16, characterized in that the Steuerervorrich¬ device (7) is in terms of control in connection with a bobbin changing device. 18. The device according to one or more of claims 14 to 17, characterized in that the Steuerervorrich¬ device (7) in terms of control with a drive (68) for a Fa is connected to the receiving device (66), by means of which it can be brought into a defined distance from the respective surface of the coil (61) under construction. 19. The device according to one or more of claims 14 to 18, characterized in that the control device (7) is assigned an input device (70) for the manual input of correction factors. 20. The apparatus according to claim 19, characterized in that the input device (70) is divided into mehre¬ re part-input devices, one of which is the input of fiber material properties affecting the bobbin diameter and another is the input of an input a thread take-up device (66) serves to play the spool (61) at the respective spinning position. 21. The device according to one or more of claims 14 to 20, characterized in that the Steuerervorrich¬ device (7) has a separate memory for each spinning station, to which the input device (70) can be optionally assigned.