EP0173118B1 - Cylindrical cross-wound bobbin - Google Patents

Description

The invention relates to a method for producing a cylindrical cheese in a wild winding from a textured, in particular false-twisted, textured thread. The end faces of such cylindrical cross-wound bobbins can lie in a normal plane (winding with straight end faces) or can be erased relative to this normal plane (biconical winding).

In this application, a cross-wound bobbin is referred to as a bobbin in a wild winding, the winding ratio of which is constant or variable in the course of the winding travel. “Spool ratio” is the ratio of the spool speed (revolutions of the spool per minute) to the traversing speed (number of double strokes per minute).

Coils of the type defined at the outset are described in DIN 61800. They are manufactured on cross winding devices of texturing machines. Because of their treatment, in particular false twist texturing treatment, the threads have curl-elastic properties there.

The current technical development is aimed at larger spools and at increasing the running speed in the further processing machines.

In order to avoid the beads at the coil ends, it is known to breathe the traverse stroke by breathing, i.e. Modify periodic shortening and lengthening in the end area of these beads.

In systematic studies of the running behavior of bobbins, it was surprisingly found that flattening the cylindrical outer surface area of the package on the side facing away from the take-off side of the thread brings about a substantial improvement in the running properties of the thread. In contrast, bead-like thickening of the bobbin on the thread take-off side, in particular due to the inevitable depositing of an excessive amount of thread in the area of the reversal of stroke, had no disadvantageous consequences. This result was completely unexpected, because, based on the known experience with the running behavior of the threads of tapered bobbins, the opposite result had been expected.

It should be mentioned that the flattening of the cylindrical outer surface area of the package is not an oblique end face, as is obtained in the production of a biconical package by a uniform reduction in the thread guide stroke, but a deliberately brought about, in particular constant, reduction in diameter at least the end of the cylindrical winding area, which is opposite the thread take-off side. In the case of bobbins which have a thread reserve winding for connecting the beginning of the thread of a bobbin to the end of the thread of a following bobbin, the flattening lies on the side of the bobbin on which the thread reserve lies.

The thread take-off side of a bobbin is further defined in that the bobbin tubes have a rounded edge on their end face facing the thread take-off side.

The production of such bobbins can be accomplished, in particular, by substantially increasing the length of the breathing strokes in cross-winding devices, the traversing devices of which, in addition to the possibility of image interference to improve the edge structure, have devices for cyclically shortening and lengthening the thread guide stroke (breathing) 20 mm stroke reduction on one or both stroke ends with a basic stroke of the traversing thread guide of 250 mm.

However, coils created in this way have relatively soft end faces. Depending on the type of further processing, this is undesirable since soft coils are more easily damaged than hard coils. Thus, the spools with flattened ends turned out to be unfavorable in many cases, particularly because of the transport and handling problems that arise, despite their favorable running properties.

However, this invention was able to maintain the advantages of the flattened end coils. At the same time, too great a softness of the coil ends is avoided and a coil with the desired, adjustable hardness is produced with excellent running properties. The invention is based on the method known from EP-PS 27 173 = US Pat. No. 4,325,517, in which the breathing stroke is continuously changed from one breathing cycle to the other as the difference between the maximum and the smallest stroke length. This process has brought about a substantial leveling of the spool structure and improvement of the run-off properties.

The object is achieved by claim 1, despite large spool diameter and long spool length, to produce spools that can be used at high take-off speeds of e.g. 1000 m / min ensure a trouble-free run of the thread overhead.

The measure according to the invention can advantageously be applied to cylindrical cross-wound bobbins with straight end faces and those with obliquely cut end faces (biconical bobbins).

The known method is thus further developed in that breathing breaths (also referred to as maximum shortening in the context of this application) of clearly different orders of magnitude are carried out in constant alternation. According to this invention there are therefore two laying cycles on top of each other, the breathing stroke in the one laying cycle being greater than, i.e. at least twice the breathing stroke in the following cycle.

In one embodiment of the invention, several breathing cycles take place within one laying cycle. Within the laying cycle with a large breathing stroke, the breathing stroke is gradually increased from one breathing cycle to the next - e.g. B. in three stages - changed, preferably reduced. In the subsequent laying cycle with a small breathing stroke, this is less than 60%, preferably less than 50% of the large breathing stroke. Within this transfer cycle, a sequence of breathing cycles has the same breathing stroke and the next sequence of breathing cycles a smaller, but again the same breathing stroke.

It has turned out to be favorable that the time ratio of the laying cycles with a large breathing stroke on the one hand and a small breathing stroke on the other hand is between 1.8 and 1.2.

In this way, the coil is built up from different winding layers. During the laying cycles with great shortening, a soft winding layer is flattened at the ends.

During the laying cycles with a small shortening, the flattened end areas of the coils are essentially filled up again and covered with a hard layer, so that the hard layer takes over the protection of the soft layer, although the soft layer below causes the flattening to a certain extent is preserved and therefore the good run-off conditions are maintained even within the hard layer.

This creates a peculiar coil that has a good external appearance and is easy to handle and that has the good running properties achieved according to the invention.

In a further embodiment of the invention, the laying cycles with a large breathing stroke and the laying cycles with a small breathing stroke follow immediately. The small breathing stroke is in turn about 40 to 50% of the large breathing stroke. Here, a single breathing cycle takes place within the laying cycles with a large breathing stroke, while within the shortening cycles with a small breathing stroke, several breathing cycles of the same size follow one another, preferably with a dead time = rest time between the individual shortening cycles. In this dead time, the traversing is carried out without shortening the thread guide stroke. It can thereby be achieved that the time in which the traversing is carried out with a large breathing stroke has a certain ratio to the time in which the traversing is carried out with a small breathing stroke. This ratio is approximately in the range from 1.8: 1 to 1.2: 1.

This is an empirically found relationship, compliance with which can be important for the run-off properties.

In this development of the method, both the large breathing strokes and the small breathing strokes are reduced in stages from one laying cycle to the next but one, the largest small breathing stroke then being more than 50%, preferably between 60 and 80% of the smallest large breathing stroke. In this sense, 2 to 10 stages, each with a reduced breathing stroke, can follow one another.

A further possibility for favorably influencing the bobbin construction and for improving the running behavior of the thread is created according to the invention in that the shortening and / or lengthening speed of the thread guide stroke can be controlled. By controlling the shortening and / or lengthening speed of the thread guide stroke, the duration of the breathing cycle can be set independently of the size of the breathing stroke. Furthermore, rest periods of any length can be set between two breathing cycles or between two laying cycles, without the total duration of a laying cycle, i.e. the duration of a laying cycle including the rest periods must be changed.

In a further embodiment of the invention it is provided that the thread guide stroke maintained between the breathing cycles, which normally corresponds essentially to the bobbin length, is temporarily narrowed. This provides a further parameter for influencing the structure of the coil and the running properties. The traversing stroke is continuously changed between two outer and two inner boundaries, the outer and inner boundaries also being changed.

According to the invention, a large number of controllable process parameters are thus provided for the construction of an exactly cylindrical coil which has a constant hardness along its length. On the one hand, the maximum shortening of the thread guide stroke as well as the duration of the respective laying cycles for large and small maximum shortening are selected. One or more of the following parameters can also be set. The number of breaths per transfer cycle; the gradation of the large and small maximum reductions within a laying cycle and in the sequence of the laying cycles; the speed of shortening and lengthening of the thread guide stroke; the rest periods by duration and number; the narrowing of the thread guide stroke between two breathing hooks or laying cycles.

The selection of these parameters depends on the type of thread, the thread titer, the thread speed and winding speed, the bobbin length and the maximum bobbin diameter, the deposit angle of the thread on the bobbin and other conditions. In this respect, the selection is to be made on the basis of tests. The importance of the invention is that, on the one hand, decisive parameters and, on the other hand, a large selection of parameters are provided, in order in any case to achieve a satisfactory coil structure and good run conditions.

As is known, the quality of a thread spool is also dependent on the tensile force with which the thread has been wound onto the spool. A particular criterion for good running properties is the uniformity of this tensile force over the thread length and over the length of the bobbin. In order to ensure a uniform thread tension, according to the invention the last-mentioned method provides that the change in the traversing speed, carried out for the purpose of the mirror disturbance, takes place between a minimum value and a maximum value in such a way that the minimum value in each case approximately half of the laying cycle with a small breathing stroke and the maximum value of Speed occurs at halfway through the laying cycle with a large breathing stroke. This means that the decrease in the traversing speed, which is caused by shortening the traversing stroke, is compensated for by an increase in the frequency of the traversing speed speed specifying double strokes, ie the number of back and forth movements of the traversing thread guide per unit of time. This control of the double stroke number takes place in such a way that its maximum coincides with the maximum large breath stroke.

According to one aspect of the invention, a further possibility of equalizing the thread tension is given by temporarily and slightly reducing and increasing the peripheral speed of the bobbin in such a way that the thread tension remains constant. With the synchronization of breathing and mirror disturbance according to this invention, only very slight changes in the peripheral speed of the coil are required for this.

In this application, half the difference between the largest and the smallest traversing path = thread guide stroke of a breathing cycle is referred to as the breathing stroke or maximum shortening.

Breathing cycle is the time in which the traversing path = thread guide stroke is shortened from the maximum traversing path to a minimum traversing path according to a predetermined law and then extended again to the maximum traversing path. A breathing stroke thus takes place within the breathing cycle.

However - especially between small breaths, especially in the idle times between two breaths - it is also possible and advantageous not to traverse with the maximum traversing stroke, which essentially corresponds to the length of the thread on the spool, but with an intermediate traversing stroke that is slightly narrowed is. The narrowing, i.e. half the difference between the maximum traversing stroke and the intermediate traversing stroke is preferably between 20 and 50% of the smallest breathing stroke.

The laying cycle is the time in which large breathing strokes (laying cycles with a large breathing stroke) or small breathing strokes (laying cycles with a small breathing stroke) are carried out.

Another possibility of obtaining the change of the traversing stroke according to the invention is that the coil is constructed with a so-called stroke shift. The length of the traverse stroke remains constant when the stroke is moved. However, the traversing stroke is shifted relative to the coil. This shift is carried out either periodically or according to predetermined intervals and for a predetermined period of time.

With this method, too, a coil can be produced which is made of alternately soft and hard winding layers. For this purpose, a large and a small stroke installation is carried out in stages in analogy to the method described above and preferably the maximum installation width is graded again within the individual installation cycles.

Embodiments of the invention are described below with reference to the drawing.

• Fig. 1 das Bewegungsdiagramm einer der Ausführungen des erfindungsgemässen Aufwickelverfahrens;
• Fig. 2 den Längsschnitt einer Spule, die nach dem Aufwickelverfahren nach Fig. 9 hergestellt ist;
• Fig. 3 die Ausführung des Bewegungsgesetzes nach Fig. 9 für eine Spule mit bikonischer Wicklung;
• Fig. 4 das Bewegungsdiagramm einer weiteren Ausführung des erfindungsgemässen Aufwickelverfahrens;
• Fig. 5 das Bewegungsdiagramm einer weiteren Ausführung mit einstellbarer Ruhezeit;
• Fig. 6 das Bewegungsdiagramm einer weiteren Ausführung mit zeitweiliger Einengung des Fadenführerhubs gegenüber der Verlegungslänge des Fadens auf der Spule.
• Fig. 1 zeigt das Bewegungsdiagramm eines erfindungsgemässen Aufwickelverfahrens, durch das in Schichten aufgebaute Spulen nach Fig. 2 erhalten werden. Im oberen Teil des Diagramms ist dargestellt, dass zum Zwecke der Spiegelstörung die Changiergeschwindigkeit nC um einen Mittelwert nCM fortlaufend variiert wird.

Show it:

• 1 shows the movement diagram of one of the embodiments of the winding method according to the invention;
• FIG. 2 shows the longitudinal section of a coil which is produced by the winding method according to FIG. 9;
• 3 shows the execution of the motion law according to FIG. 9 for a coil with a biconical winding;
• 4 shows the movement diagram of a further embodiment of the winding method according to the invention;
• 5 shows the movement diagram of a further embodiment with adjustable rest time;
• Fig. 6 shows the movement diagram of another embodiment with temporary narrowing of the thread guide stroke compared to the length of the thread on the spool.
• FIG. 1 shows the movement diagram of a winding method according to the invention, by means of which coils according to FIG. 2 built up in layers are obtained. The upper part of the diagram shows that for the purpose of mirror interference, the traversing speed nC is continuously varied by an average value nCM.

The lower diagram shows that breathing is synchronized with the mirror disorder, which has a positive effect on the course of the thread tension.

Breathing is - as can be seen here - the shortening of the traversing stroke H. The greatest traversing stroke in cylindrical coils with straight end edges essentially corresponds to the coil length. For biconical bobbins that have conical end edges, the greatest traversing stroke corresponds to the length of the thread on the bobbin (Fig. 2). The traversing stroke H is also referred to as thread guide stroke in the context of this application. The jagged curves indicate the position of the reversal points U of the traversing thread guide and thus - measured from the abscissa - the shortening A of the traversing stroke H. Some reversal points U are marked. The shortening A on one side of the coil. i.e. half the difference between the largest and the smallest thread guide stroke within one breathing cycle is also referred to as the breathing stroke.

Several - shown and advantageous two - laying cycles are carried out. Within the first laying cycle, the traversing stroke H is shortened very much up to the greatest maximum shortening Amax / max = largest breathing stroke. However, this first laying cycle consists of several breathing cycles, whereby successive breathing cycles of the first laying cycle in turn have different maximum reductions = breathing strokes. Very good results were obtained when three breathing cycles were carried out within one laying cycle, with the largest breathing stroke, i.e. the greatest shortening Amax / max = 19.2 mm and the smallest breath, i.e. the smallest maximum shortening Amax / min was 13.8 mm. Good results were also achieved with four grades. Within a laying cycle, the smallest breath stroke Amax / min should be at least 50%, preferably more than 60% of the largest breath stroke Amax / max.

Following the laying cycle with a large breathing stroke Amax, there was a laying cycle with a small breathing stroke. Both relocation cycles have approximately the same length of time, so that the same layer thicknesses of yarn result in the two laying cycles. Here, however, there are possible variations through which the hardness or softness of the coil can also be influenced.

Within the installation cycle with a small breathing stroke Amin of the traverse stroke, the breathing strokes were again graded between amine / max and amine / min. Several breathing cycles with the same breathing stroke were carried out in succession before the shortening was taken back to the next level. It also applies here that the smallest of the small breaths amine / min should be at least 50%, preferably more than 60% of the largest of the small breaths amine / max. On the other hand, the small amine breaths are less than a third of the large Amax breaths, preferably less than a quarter of the large breaths. Here, too, there are possible variations through which the hardness of the spool and the running properties can be influenced.

It can also be seen from the diagrams that the laying cycles with the large breathing stroke take place synchronously with the mirror disturbance, and that the individual laying cycles merge into one another essentially without rest. For this purpose, the rate of shortening of breathing is changed from one laying cycle to the other laying cycle in such a way that synchronization with the mirror disturbance cycle is achieved. The shortening rate of breathing is the shortening of the thread guide stroke per one reciprocating movement (double stroke) of the traversing thread guide. The shortening speed is proportional to the pitch angle of the zigzag straight line shown in FIG. 1, which designate the respective reversal points of the thread guide stroke. Correspondingly, the extension speed is the increase in the thread guide stroke per one double stroke of the traversing thread guide and is proportional to the pitch angle of the descending branch of the straight line mentioned.

In the course of the laying cycle with a small breathing stroke, the switchover to a breathing cycle with the next smallest breathing stroke takes place synchronously with the cycle of the mirror disturbance; within the time period of a mirror disturbance cycle, however, breathing is performed with a constant breathing stroke.

The biconical coil constructed in this way, which is partially shown in axial section in FIG. 2, consists of a multiplicity of differently constructed layers, of which six layers are shown. The winding layers, which are made with a large breath stroke and accordingly have flattened but soft ends, are cross-hatched. The winding layers, which are made with a small breathing stroke and thus hard ends, are filled in. It can be seen that these hard winding layers essentially fill up the flattened end regions of the preceding winding layers, so that essentially hard winding layers are exposed on the end face of the coil, as can be seen in FIG. 2.

It should be emphasized that the coil shown in FIG. 2 is wound biconically. The modification of the breathing diagram required for this is shown in FIG. 3.

It differs from the diagram drawn in FIG. 1 only in that a further shortening B of the traversing stroke is superimposed on the breathing, ie the shortening A, for the purpose of biconical formation of the coil. The shortening B progresses in the course of the bobbin travel in proportion to the winding structure, so that the length of the thread on the bobbin also decreases in relation to the bobbin length.

4 shows the movement diagram of a further winding method according to the invention. The advantage of this method is that the thread layers, which were produced with a large breathing stroke and are therefore relatively soft or have relatively soft ends, are only very thin and, after the laying cycle with a large breathing stroke, are incorporated in an immediately following shortening cycle with a small breathing stroke and be determined. As a result, the homogeneity of the coil with regard to its hardness can be improved to an even greater extent than with the coil according to FIG. 2.

The end of the traversing stroke H is shown in the lower half of the movement diagram according to FIG. 4. In the upper half, the traversing speed NC is shown with the dimension double strokes per minute.

It can be seen from the lower half of the diagram that the traversing stroke H is continuously changed in length. On the one hand, there is a constant shortening B of the traversing stroke, which is required to produce a biconical coil. It should be mentioned here that this shortening is generally the same at both ends of the coil, so that a coil which is symmetrical with respect to the central normal plane is produced.

There is also a shortening called breathing A. The breathing strokes are divided into two size categories: Amax denotes the large breathing stroke, amine denotes small breathing strokes. Large and small breaths follow in constant change. One breathing stroke takes place during one laying cycle and several small breathing strokes take place in the following laying cycle. The small breaths of a laying cycle are the same size. Between the breathing cycles with small breaths there are dead times (rest periods) in which there is no shortening of the traversing stroke for the purpose of breathing (but probably for the production of biconicity).

The greatest shortening length of the large breaths, i.e. the largest large breathing stroke is designated Amax / max. The lower half of the diagram shows that the largest breaths do not remain constant, but decrease in steps. The smallest large breathing stroke is designated Amax / min.

The largest small shortening length, ie the largest small breathing stroke is with amine / max be draws. The lower half of the diagram shows that the small breathing stroke also decreases in stages. The smallest small breath is called amine / min.

The dead times between the small breaths are so long that the time ratio Tmax / Tmin - TT is between 1.8 and 1.2. A preferred value is 1.5. Tmax is the duration of the laying cycle with a large breathing stroke (Amax), Tmin is the duration of the laying cycle with a small breathing stroke and TT is the dead time between the small breathing strokes.

It can also be seen from the lower half of the diagram that the reduction of the large breaths between Amax / max and Amax / min and the reduction of the small breaths between Amine / max and Amine / min are carried out in the same sense. That means: Amax / max and Amin / max follow each other immediately and also Amax / min and Amin / min.

The overall diagram shows that the change in the traversing speed for the purpose of mirror interference is synchronized with the shortening of the traversing stroke in such a way that the tip of the large breathing stroke coincides with the maximum traversing speed. The minimum of the traversing speed, on the other hand, lies in the middle of the laying cycle Tmin with a small breathing stroke (amine). This type of synchronization achieves, on the one hand, the desirable result that the increase in the traversing speed for the purpose of mirror interference is compensated for by the lowering of the traversing speed, which tends to - i.e. for a given double stroke rate - is associated with the shortening of the traversing stroke.

On the other hand, it is avoided that the change in the traversing speed takes place asymmetrically for the purpose of the mirror disturbance, as is sketched into the diagram with dashed lines (line 1) at the right end of the upper part of the diagram. Such an asymmetrical law of motion has the disadvantage that the traversing speed is reduced very slowly and therefore there is a risk that possible mirror areas are passed through very slowly and therefore the mirror symptoms are not effectively prevented.

The shortening length of the large Amax breaths is between 10 and 20 mm. The shortening length of the small breaths amine is between 2 and 5 mm.

It should be mentioned that the laying cycles do not have to remain constant during the winding cycle. In particular, the duration of the shortening cycles can be increased. However, the time ratio Tmax / Tmin - TT preferably remains constant.

Another exemplary embodiment explained with reference to FIG. 5 is characterized in that by changing the shortening and lengthening speed of a breathing cycle, not only the time ratio Tmax / Tmin -TT, but also additionally the proportion of the dead time is predetermined and also a desired synchronization with the mirror disorder can be performed.

It can again be seen from the lower half of the diagram that the traversing stroke is shortened B over time in order to produce a biconical coil. There is also a shortening called breathing A. The breath strokes are again divided into two size categories, which follow one another in constant alternation. A laying cycle Tmax with a breathing cycle and a large breathing stroke is followed by a laying cycle Tmin with a breathing cycle with a small breathing stroke and a resting time TT. The duration of Tmax is not only determined by the size of the maximum breathing stroke, but also by the selection of the shortening and lengthening speed of the traversing stroke H. The duration of the breathing cycle with a small breathing stroke = Tmin - TT is also determined by the small breathing stroke and by appropriate selection of the shortening and lengthening speed, in such a way that the following synchronization with the mirror disturbance results. The mirror disturbance diagram is shown in the upper half of the diagram of FIG. 5. The closed zigzag curve shows the traversing speed, which is changed symmetrically by an average traversing speed nCM. The breathing parameters are now coordinated so that the largest breathing stroke with the highest traversing speed and the end of the breathing cycle with small breathing stroke coincides with the lowest traversing speed. As already mentioned, this kind of synchronization of mirror disturbance and breathing brings about an equalization of the thread tension.

The change in the shortening and / or lengthening rate from one breathing cycle to the other or one laying cycle to the other therefore gives the advantageous possibility of coordinating the temporal sequence of the mirror disturbance and the temporal sequence of breathing.

It has now been found that a particularly inexpensive, uniform coil structure with an even hardness and good running properties can also be produced by the fact that breathing does not always start from the traversing stroke ends that determine the coil length and coil shape. Rather, traversing stroke ends, i.e. the outer limits of the traversing stroke in this method are temporarily shifted towards the center of the spool, preferably with an amount between 1 mm and 10 mm. The breathing stroke - also referred to as "shortening length" in the context of this application - is based on this shifting stroke end. This means that the outer limit of the laying length of the traversing is temporarily narrowed. This narrowing preferably takes place during the laying cycles with a small maximum shortening, i.e. small breath. It is also possible to lay the inner limit of the traverse stroke in the same or opposite direction or to leave it constant.

Fig. 6 shows a traversing method, in which such a narrowing of the traversing stroke compared to the length of the thread on the bobbin takes place, namely both relocated the outer as well as the inner limits of the traverse stroke. This ensures that the breathing stroke, which is the distance between the inner and outer limits of the traverse stroke, can be carried out on the one hand over changing areas of the coil length and on the other hand with changing size.

The end region of the traverse stroke H is again shown in the lower half of the movement diagram according to FIG. 6. The traversing speed nC is shown in the upper half with the dimension double strokes per minute. The process of mirror disorder, i.e. the change in the traversing speed nC for the purpose of mirror interference is identical to the method described for FIGS. 4, 5.

It can be seen from the lower half of the diagram that the traversing stroke H is continuously changed in length. On the one hand, there is a constant shortening B of the outer limit of the traversing stroke, which is necessary to produce a biconical coil. This shortening B defines the outer limit of the traversing stroke in the diagram according to FIG. 6. It should be mentioned here that the shortening B is generally the same at both ends of the coil, so that a coil is formed which is symmetrical with respect to the central normal plane. The traversing stroke between these ends of the coil is referred to as the installation length. This laying length or the shortening B also determines the edges and at least the desired ideal shape of the coil in the method according to FIG. 6.

While a method is described with reference to FIGS. 1.3 to 5, in which the traversing stroke is shortened on the basis of this laying length, the laying length is temporarily narrowed according to FIG. the outer limit of the traversing stroke was also temporarily shifted inwards. In Fig. 6 the breathing cycles are again divided into two size categories: Amax denotes the large breathing stroke, Amin denotes small breathing strokes. Breathing cycles with large and small breathing strokes follow in turn. Several small breaths are made during a laying cycle. The greatest shortening length of the large breaths, i.e. the largest large breathing stroke - also known as the breathing amplitude - is designated Amax / max. The largest small shortening length, i.e. the largest small breathing stroke - also known as a small breathing amplitude - is called amine / max. This means that - as in the method according to FIG. 5 - the inner limit of the traversing stroke is continuously changed.

In the method according to FIG. 6, the laying length is now also temporarily narrowed and thus the outer limit of the laying is shifted inwards, namely the laying length is initially very strongly narrowed after the laying cycle with a large breathing stroke. The amount V of the restriction is measured at one end of the coil and is e.g. 8 mm. The subsequent laying cycle with a small breathing stroke now takes place on the basis of this narrow laying length. The traversing stroke is carried out over the entire restricted installation length during the dead times TT.

This is followed by a laying cycle with a large breathing stroke, but the shortening length overall is smaller than the shortening length in the previous shortening cycle with a large breathing stroke. In the next laying cycle with a small laying length, the amount V by which the laying length is narrowed, i.e. the laying limit is laid e.g. to 6 mm. Breathing takes place on the basis of this installation length. The breathing stroke of this laying cycle is smaller than the breathing stroke of the previous laying cycle with a small breathing stroke.

In the following laying cycles, the large breathing stroke, the small breathing strokes and the narrowing V of the laying length continue to be reduced. Such a breathing section with a narrow installation length can in turn be followed by a breathing section according to the diagram shown in FIG. 4 or 5.

This method enables breathing to be carried out in the area of the coil end in which this is necessary or desirable in order to achieve a good, uniformly hard coil structure and good run-off properties. This significantly extends the winding technology.

Fig. 7 shows an apparatus for winding a thread on a bobbin according to the inventive method. In this figure, reference is made to U.S. Patent No. 3,730,448, which is shown in FIG. 3 of the German patent 1 916 580 essentially coincides. To the reference numerals in FIG. 3 of US Pat. No. 3,730,448, 100 were added to identify identical parts in FIG. 7 of this invention.

Short description:

7, a coil 102 is formed on the coil sleeve 101. The spool is driven by friction roller 105 on shaft 106. The shaft is driven by motor 50 via a frequency converter 51. The changer 107 consists of a thread guide 108 with an angle lever 109 which is rotatably mounted on pins 110. The pin 110 is fastened to a slide 111 which is driven by the sliding shoe 113. The sliding block 113 moves in a screw-shaped or spiral-shaped groove 114 on a cam drum 115. The sliding block 117 is guided in the guide rail 118 and is rotatably mounted on the pin 116 at the other end of the angle lever 109. The guide rail 118 is rotatably mounted in the pivot point 120. The traversing stroke of the thread guide 108 is dependent on the inclined position of the guide rail 118.

Cam head 135, which is fastened to rod 126, is used to adjust the inclined position of guide rail 118. Rod 126 is associated with a series of rewinder units arranged side by side and has a central drive which will be described below. The working surface 136 of the cam head 135 acts on the guide rail 118 via transmission cams 128 and transmission link 129 and thus determines the inclined position of the guide rail 118 and consequently the length of the traversing stroke. With the help of the transmission link 129, coils 102 with biconical ends manufactured by shortening the traversing stroke depending on the increasing diameter of the coil 102. In this connection, reference is made to the description of the aforementioned U.S. Patent 3,730,448. To produce spools with straight edges, the guide rail 118 is moved to the left and locked (this will be discussed later), so that the cam head 123 is operatively connected to the shoulder 138 on the guide rail 118 via its working surface 137. In this position, the transmission link 129 is out of operation due to the greater inclination of the guide rail 118.

In addition to what is shown in FIG. 3 of US Pat. No. 3,730,448, devices for driving and adjusting the rail 126 are shown in the left part of FIG. 7 of this description. These devices (shown schematically) consist of a program unit 18, a signal / current converter 19, an electromagnet 20, the magnetic force of which is transmitted to a hydraulic control valve 21, a spring 22 and to the piston of the cylinder-piston unit 23. The piston rod 24 is connected to the end of the adjusting rod 126. The group consisting of magnet 20, control valve 21, spring 22 and cylinder-piston unit 23 is arranged on slide 25. This group is shown in detail as unit 26 in FIG. 8.

The unit 26 comprises the electromagnet 20, the hydraulic control valve 21, the spring 22 and the cylinder-piston unit 23. The iron core 27 of the magnet 20 acts on the piston rod 28 of the control valve 21. The piston rod 28 has three control collars 29, 30, 31 , which serve to control the connecting lines between the pump 32, tank 33 and the rear 34 of the cylinder-piston unit 23. The spring 22 acts on the other side of the piston rod 28 via a corresponding spring plate 35. The other end of the spring 22 acts on the spring plate 36 and the piston 37 of the cylinder-piston unit 23. The piston 37 is a differential piston because of its end face 38 is reduced by the area of the piston rod 24. The end face 38 of the piston 37 is permanently connected to the pump 32 via channel 39. The rear 34 of the piston 37 is connected both to the pump 32 via channel 40 and to the tank 33 via channel 41. This connection is controlled by moving the control collar 30, which connects the channel 41 to both channel 40 and channel 42.

One arm 43 of the channel 42 leads to the rear 34 of the cylinder-piston unit 23. The other arm 44 serves to compensate for the pressure that prevails on both sides of the hydraulic control valve. It should be noted that piston 37 abuts a shoulder 45 of the cylinder in its outer left position. As a result, the outermost stroke ends of the coil are mechanically fixed.

In FIG. 8 it can also be seen that the unit 26 is mounted on a slide 25. The carriage is fastened on two parallel rods 49 which slide in slide bearings 46. The carriage 25 is displaceable between two positions, one position being limited by a stop 47 and the other position by a stop from flange 48 to slide bearing 46.

In operation, one of the winding programs shown in the previous drawings and diagrams is stored in the program unit 18. The program unit generates an output signal which corresponds to a certain traverse stroke length in accordance with one of the traverse programs according to this invention. This output signal is converted by the converter 19 into an electrical current, which activates the magnet 20. The magnetic force is transmitted to the piston rod 28 of the control valve 21, to the spring 22 and to the piston 38 and piston rod 24.

The function of the unit 26 will be described with reference to the position of the control valve 21 shown in FIG. 8. A specific output signal is converted into a current which exerts a force on the iron core 27, which then pushes the piston rod 28 with the control collar 30 into the position shown. In this position, channel 42 is closed. Consequently, the end face of the cylinder-piston unit 23 is acted upon by the liquid flow coming from the pump 32. The back 34 is closed. as a result, piston 37 and piston rod 24 are locked in the position shown.

If the output signal of the program unit is changed in such a way that a stronger current acts on the electromagnet 20, a stronger force in turn acts on the iron core 27, which moves the iron core 27 to the right. Channel 42 then opens to channel 41, which leads to tank 33. A pressure drop now arises on the rear side 34 of the cylinder-piston unit 23, and the pump pressure acting on the front side 38 displaces the piston 37 and the piston rod 24 to the left. As a result, the spring 22 is compressed, and the resulting spring force causes the piston rod 28 of the control valve 21 to be displaced to the left, whereupon the control collar 30 interrupts the connection of the channel 42 to the channel 41 and thus to the tank. Thus, the force of the iron core 27 is balanced by the spring 22. Conversely, when the current is decreased, the spring 20 moves the piston rod 28 to the left, and collar 30 opens the channel 42 to the arm 40 leading to the pump. The pump pressure is now applied to both sides of the piston 37. Since the active area on the rear side 34 is larger than the active area on the front side 38, the piston 37 is moved to the right. As a result, the spring 22 expands and the spring force acting on the piston rod 28 decreases. Due to the magnetic force acting on the iron core 27, the piston rod 28 is now moved to the right, so that collar 30 closes the connection between channel 42 and pump channel 40.

From this description it can be seen that the input current acting on the electromagnet 20 causes a certain position of the piston 37, the piston rod 24 and consequently the rod 126 and thus the inclination of the guide rail 118. The traversing stroke length of the thread guide 108 shown in FIG. 7 is thus controlled by the output signal of the program unit 18.

As already mentioned, unit 26 is on slide 25 stored. In the position shown, in which the flange 48 bears against the stop 37, the unit 26 and the rod 126 are positioned in such a way that the inclined position of the guide rail 118 is now determined by means of the cam head 135 on the rod 125. If the slide 25 and the unit 26 are in this position, biconical coils 102 are produced. If the slide is in the other position, in which the flange 48 bears against the sliding bearing 46, the cam head 123 of the rod 126 is in operative connection with the shoulder 138 on the guide rail 118, as a result of which coils 102 with flattened end regions are formed.

FIG. 7 also shows that shaft 106 on friction roller 105 is driven by motor 50. Motor 50 is controlled by the output signal of frequency converter 51. The cam drum 115 is driven by motor 52. Motor 52 is controlled by the program unit 53, whereby the traversing speed is changed to prevent unwanted mirrors on the formed roll. The frequency converter 51 is controlled on the one hand by the output signal of the program unit 18, by which the breathing is influenced according to this invention, and on the other hand by the output signal of the program unit 53, by which the traversing speed is changed. As a result, changes in the tension of the thread to be wound on the bobbin 102, which are caused either by breathing and / or the change in the traversing speed, can be compensated for by slight changes in the peripheral speed of the friction roller 105 and the bobbin 102. Timer 54 coordinates the output signals of the program units 18 and 53, via which the breathing and the change in the traversing speed are controlled according to this invention and in particular according to the diagrams shown.

Claims (23)

1. Process for the production of a cross wound bobbin (102) in irregular winding by traverse motion of the thread with the thread guide stroke (H) shortened from time to time (breathing A), the maximum shortening (Amax/max, Amin/max) (breathing stroke), of the thread guide stroke (H) changing from one breathing phase to another, characterised in that the thread guide stroke (H) takes place with varying maximum shortening (Amax/max, Amin/max) in such a manner, especially at the end of the bobbin (102) remote from the reeling off end, that deposition or traversing cycles with large maximum shortening (Amax) and small maximum shortening (Amin) continuously alternate, the small shortenings (Amin) amounting to less than 60% of the large shortenings (Amax) and the large shortening (Amax) preferably amounting to 10 to 20 mm and the following, small shortening (Amin) preferably amounting to 2 to 5 mm.

2. Process according to claim 1, characterised in that the speed of shortening and/or lengthening of the thread guide stroke is controllable.

3. Process according to claim 2, characterised in that the speed of shortening and/or lengthening of the thread guide stroke (H) is controllable in such a manner that the duration of the deposition cycles (Tmax, Tmin) with large maximum shortening (Amax) and with small maximum shortening (Amin) is constant.

4. Process according to one of the claims 1 to 3, characterised in that a resting period (TT) in which traversing takes place with a constant thread guide stroke (H) occurs between two breathing strokes (A) and/or between two deposition cycles (Amax, Amin).

5. Process according to claim 3 or claim 4, characterised in that the speed of shortening and/or of lengthening can be controlled so that the duration of the deposition cycles with small maximum shortening (Tmin) including the predetermined resting period (TT) is equal to the duration of the deposition cycles with large maximum shortening (Tmax).

6. Process according to claim 4 or claim 5, characterised in that between two breathing phases and/or deposition cycles (Amax, Amin), the thread guide stroke (H) during at least some of the resting periods (TT) takes place with a constant constriction (V) compared with the length of deposition (L) of the thread on the bobbin (102), this constriction (V) being less than the small maximum shortening (Amax/min) of the breathing stroke (Amax).

7. Process according to one of the preceding claims, characterised in that several breathing phases are carried out within the deposition cycles with maximum shortening (Amax) and/or within the deposition cycles with minimum shortenings (Amin).

8. Process according to claim 7, characterised in that the maximum shortening (Amax/max, Amin/ max) of the breathing phases successively taking place within one deposition cycle (Amax, Amin) increases or decreases step wise and within such a deposition cycle (Amax, Amin) the smallest maximum shortening (Amax/min) preferably amounts to 50 to 100% of the greatest maximum shortening (Amax/max).

9. Process according to claim 7 or 8, characterised in that a single breathing phase takes place within a deposition cycle with large maximum shortening (Amax) and several breathing phases are carried out within the next following deposition cycle with small maximum shortening (Amin).

10. Process according to claim 9, characterised in that within the deposition cycles with small maximum shortening (Amin), the maximum amount of shortening (Amin/max) decreases or increases from one breathing phase to another.

11. Process according to claim 10, characterised in that within the deposition cycle containing several breathing phases with small maximum shortening (Amin), a resting period (TT) occurs between individual breathing phases, during which resting period the traverse motion is carried out without shortening of the thread guide stroke (H).

12. Process according to claim 11, characterised in that the proportion of time taken up by resting periods within the deposition cycle with small maximum shortening (Tmin) is such that the time ratio TG/TK is in the range of from 1.8 to 1.2, TG being the duration of a deposition cycle with large maximum shortening (Tmax) and TK being the sum of the durations of individual breathing phases within a deposition cycle containing small maximum shortenings (Amin), i.e. the duration (Tmin) of the deposition phase with small maximum shortening (Amin) minus the resting periods (TT).

13. Process according to one of the preceding claims, characterised in that the shortening time and lengthening time of the thread guide stroke (H) within one breathing phase (Amax, Amin) follow one another substantially without a resting period (TT).

14. Process according to one of the preceding claims, characterised in that shortening of the thread guide stroke (H) is more frequent and/or of longer duration in the region of one end face of the bobbin (102) than in the region of the other end face.

15. Process according to the preceding claims, characterised in that for the construction of an exactly cylindrical bobbin (102) with the hardness distributed uniformly along the length of the bobbin (102), the magnitude of the large (Amax) and small (Amin)maximum shortenings and the duration (Tmax, Tmin) of the deposition cycles for large (Amax) and small (Amin) maximum shortenings and the time ratio (TG/TK) in relation to one another are predetermined and in addition at least one of the following parameters is laid down: number of breathing strokes (A) per deposition cycle (Amax, Amin); gradation of the large and small maximum shortenings within a deposition cycle (Amax, Amin); speed of shortening and speed of lengthening; resting periods (TT) as to duration and number; constriction (V) of the thread guide stroke (H) between two breathing phases (Amax. Amin) compared with the (total) length of deposition of the thread on the bobbin (102).

16. Process according to one of the preceding claims, characterised in that breathing (A) is accompanied by a continuous change in the traverse motion speed (nC) between a minimum value and a maximum value, the minimum value invariably occurring halfway through a deposition cycle with small maximum shortening (Amin) and the maximum value of the traverse motion speed occurring halfway through the deposition cycle with large maximum shortening (Amax), i.e. when the maximum large shortening (Amax/max) takes place, the deposition cycles (Amax, Amin) having substantially the same duration (Tmax, Tmin + TT).

17. Process according to claim 16, characterised in that the speed of shortening and the speed of lengthening of the thread guide stroke (H) are predetermined so that the frequency of breathing (A) is equal to the frequency of depatterning.

18. Process according to one of the claims 15 to 17, characterised in thatthe circumferential speed of the bobbin is controlled or regulated in dependence upon the breathing parameters and the depatterning so that the thread tension remains substantially constant.

19. Apparatus for winding textile threads to form a bobbin (102) on a tube (101), comprising devices (105) for driving the bobbin (102) at a substantially constant circumferential speed and traverse motion devices (107) for reciprocating the thread over the length of the bobbin and a breathing device by which the thread guide stroke (H) of the traverse motion device (107) is shortened from time to time and the maximum amount of shortening (Amax, Amin) changes from one breathing phase to the next, characterised in that the breathing device contains a control device (18, 19, 25, 26, 126) by which the breathings is sub-divided into deposition cycles (Amax, Amin) with large and small maximum shortening constantly alternating.

20. Apparatus according to claim 19, characterised in that the breathing device contains a program memory (18) for storing a series of signals representing the continuous shortening and subsequent lengthening of the thread guide stroke (H).

21. Apparatus according to claim 20, characterised in that the output signal of the program memory (18) is fed as current to an electromagnet

(20) the magnetic force of which deflects a guide rail (118) in which the free end of the traverse motion thread guide (108) which is in the form of a toggle lever (109) is slidably guided.

22. Apparatus according to claim 21, characterised in that the magnetic force is transferred by a hydraulic or pneumatic control device (26) by means of the magnetic force first acting directly on the piston (29-31) of a control valve (21) and the piston (28-21) of the control valve (21) being in force transmitting connection by means of a spring (22) with the adjustment piston (37) which is hydraulically or pneumatically activated by the control valve (21).

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