EP0754790B1 - Method and apparatus for heating a synthetic yarn - Google Patents

Description

The invention relates to a method and a device for heating a synthetic thread according to the preamble of claims 1 and 19, respectively.

This method and apparatus are known by e.g. U.S. Patent 3,103,407.

In the method and the device, a freshly spun synthetic thread (polyester) is conveyed by means of a Abzugsgalette from a spinning zone in a drawing zone and stretched between the Abzugsgalette and a Verstreckgalette. Here, the thread is heated by means of the heated withdrawal godet and a directly adjacent heated metal plate in two stages by contact. The withdrawal godet is in this case heated to a temperature of 60 to 90 ° C and the metal plate to a temperature of 160 to 200 ° C. The take-off speed is in the range of less than 1,000 m / min.

In this method, it is disadvantageous that the heating of the thread depends exclusively on the contact between the heated surfaces and the thread. In addition, the large contact length and the contact force leads to increased yarn friction, which adversely affect the quality of the thread. These effects increase rapidly at higher take-off speeds, so that even heat transfer is not possible.

The object of the invention is the thermal treatment of a running synthetic thread - it may be polyester, but in particular also polyamide, polytrimethylene terephthalate and polypropylene act - to achieve a uniform heating of the thread with a correspondingly uniform stretching and uniform, well-adjustable thread properties.

The solution of the problem arises from the claims 1 and 19.

It is envisaged that the surface temperature of at least one of the heating surfaces is higher than the melting temperature of the thread material, preferably higher than 100 Kelvin above the melting temperature of the thread material and that the thread is subjected to a thread tension required for plastic deformation.

Due to the high temperature of the heating surface, a shock-like heating of the thread is effected immediately after entering the heating zone. On the one hand, this allows the so-called draw point to be precisely located. The draw point is a very narrow portion of the thread where plastic deformation begins by smooth flow. On the other hand, the shock-like heating causes structural transformation to take place preferentially. The friction-induced mechanical stress of the thread is reduced to a minimum, so that the yarn tension, which is required for plastic deformation, has a stable course.

A particular advantage is that in the continuous drawing and fixing the yarn tension does not need to be increased but can remain substantially constant. Due to the shock-like heat treatment, a sufficiently good fixing effect is achieved with the draw tension. Another advantage is that means such. As godets, can be omitted to increase the yarn tension between the individual stages of the heat treatment.

The process variant according to claim 3 can be used advantageously wherever materials are processed, such as. As polypropylene, which require a Nachverstreckung.

The process variant according to claim 4 has the advantage that the heat treatment in the first stage can be done in particular by a heated draw pin such that despite low contact length and high take-off speeds, the high surface temperatures cause a formation of the draw point on the draw pin. The draw pin may have a curved surface with a radius of, for example, 10 cm or even higher. It is stationary and not rotating. His coat is partially touched or entwined by the thread. Due to the high surface temperatures, the contact length and the contact force can be kept very small. As a result, the wear of the draw pins is reduced. In addition, very low frictional forces on the thread, so that thread damage can be avoided.

It is expressly understood that the draw pin can also be replaced by a plate which is touched by the thread.

The invention consciously turns away from the "only" contact-free thread guide. According to claim 5, the heat transfer takes place in the first stage by contact, which is designed so that only small frictional forces on the thread arise. The first stage of the heat treatment can be carried out in particular by a hot galette, through which the thread is withdrawn from the spinneret. This galette is located at a point where the freshly spun thread is again significantly cold (about 40 ° C). This galette can be heated to a temperature of 70 to 120 ° C. By a subsequent Verstreckgalette the thread is withdrawn from the first godet with such a thread tension that immediately at the expiration of Thread from the galette of the draw point trains. Alternatively, take the place of the deduction godet from an internally heated draw pin or a heated plate. The contact length on the draw pin is so small that the resulting frictional forces are just sufficient that the flow occurs for the first time at the draw pin and accordingly forms a draw point. The draw pin thus acts as a braking surface, similar to DE 38 23 337 = bag. 1590. In the second stage, however, the thread is substantially contactless, that is guided with very precise guidance at a close distance to a heating surface, which is heated to a temperature between 350 and 550 ° C. The distance between the thread and the heating surface is in the range of 0.5 to 3.5 mm, so that when entering the heating zone, the thread is heated in a shock.

The leadership of the thread is done by thread guides, on the one hand for a smooth running of the thread, on the other hand, but also ensure the exact distance to the heating surface.

In a third stage, the thread may then also be guided without contact and in close proximity to another heating surface, which is heated to a temperature between 300 and 500 ° C in another embodiment.

The embodiment according to claim 8 allows a very accurate adjustment of the stretching ratio. The directly heated draw pin reliably guides the draw point even at take-off speeds above 5,000 m / min.

The process variant according to claim 9 has the advantage that larger wrap angles for generating high yarn tension forces are possible. The method modification according to claim 11 offers the advantage that the entrained spinning heat can be used already in the first stage of the heat treatment. The leadership of the thread over a curved heating surface can be omitted here. With this, take-off speeds in the range of 6,000 to 7,500 m / min can be achieved.

The development according to claim 12 results in a very simple procedure.

The process variant according to claim 14 has the advantage that the yarn forms a precisely localized draw point at low draw tension and. already undergoes a preferred microstructural transformation in the first stage of drawing due to the shock-like heating.

The method can be applied to all common types of polymers. For the mechanical properties of threads, it may be advantageous that they are spun from a recipe of different polymers. For example, it is known that the addition of up to 5% PBT (polybutylene terephthalate) to PET improves the spinnability and elastic properties of the fibers.

Polypropylene having a narrow molecular weight distribution in the range of less than 3, in particular metallocene-based, types can preferably be processed by this process.

The device is characterized in that here a very short heater is made possible, but on the other hand has the advantage of its design that a very targeted, matched to the speed of the thread temperature control in the thread and over the length of the thread very uniform heating is possible. The shock-like heat supply at the onset of flow prevents disturbance of the crystal structure and thus allows optimal orientation of the thread molecules.

The shock-like heat supply in the first stage of heating leads abruptly to reach the drawing point and also reduces the contact length and contact force.

The development of the device according to claim 22 has the advantage that it can be easily operated, in particular, the thread can be easily inserted. The monitoring is also possible.

The embodiment according to claim 23 ensures a quiet thread guide and also allows a customized temperature control. As a result, the strength, extensibility and shrinkage tendency of the thread can be very largely influenced and adjusted to desired values.

The embodiment according to claim 24 serves to fix the yarn path relative to the heated surface but also to calm the yarn path.

The embodiment according to claim 25 and 26 is shown in terms of machine technology. The looping of the thread on the draw pin can be very easily adjusted by the positioning of the draw pin that, taking into account the temperature of the draw pin, the yarn tension is increased so that forms on the draw pin of the draw point. In this embodiment, it is also possible to work without Abzugsgalette, which is on the one hand technically simple, but on the other hand also allowed to use the entrained heat from the spinning zone in the thread already for the formation of the drawing point.

If the hiding according to claim 29, there are very extensive adjustment options for the draw ratio and thereby caused Orientation and other properties of the thread.

Fig. 1

zeigt schematisch ein Spinnverfahren und die dazu erforderlichen Vorrichtungsteile in dem Verfahren und Vorrichtung nach dieser Erfindung angewandt werden;

Fig. 2

zeigt eine Modifikation des Verfahrens und der Vorrichtung;

Fig. 3

zeigt eine Ausführungsform einer Heizeinrichtung;

Fig. 4

zeigt eine Modifikation der Verstreckzone und deren Vorrichtung;

Fig. 5

zeigt eine weitere Modifikation der Verstreckzone und der Vorrichtung;

Fig. 6

zeigt eine galettenlose Verfahrensvariante und deren Vorrichtungsteile.

Soweit nicht anders gezeigt, gilt folgendes für Fig. 1 + 2.In the following embodiments of the invention will be described with reference to Figures 1 to 6.

Fig. 1

Fig. 12 schematically shows a spinning process and the apparatus parts required therefor in the method and apparatus according to this invention;

Fig. 2

shows a modification of the method and the device;

Fig. 3

shows an embodiment of a heater;

Fig. 4

shows a modification of the drawing zone and its device;

Fig. 5

shows a further modification of the drawing zone and the device;

Fig. 6

shows a galettelose process variant and its device parts.

Unless otherwise shown, the following applies to Fig. 1 + 2.

A thread 1 is spun from a thermoplastic material. The thermoplastic material is fed by a filling device 2 to the extruder 3. The extruder 3 is driven by a motor 4. The engine 4 is controlled by a motor controller 49. In the extruder 3, the thermoplastic material is melted. This is done on the one hand, the deformation work (shear energy), which is introduced by the extruder in the material. In addition, a heater 5, z. B. in the form of a Resistance heating provided, which is controlled by a heating controller 50. Through the melt line 6, in which a pressure sensor 7 is provided for measuring the melt pressure for a pressure-speed control of the extruder, the melt passes to the gear pump 9, which is driven by the pump motor 44. The pump motor is controlled by the pump control 45 such that the pump speed is sensitive adjustable. The pump 9 conveys the melt stream to the heated spin box 10, on the underside of which the spinneret 11 is located. From the spinneret 11, the melt exits in the form of fine filament strands 12. The filament strands pass through a cooling shaft 14. In the cooling shaft 14, an air flow 15 is directed transversely or radially onto the filament bundle 12 by blowing. This cools the filaments.

At the end of the cooling shaft 14, the filament bundle is combined by a preparation roller 13 or a preparation pin to form a thread 1 and provided with a preparation liquid.

Only for the embodiment according to FIG. 1:

The thread is withdrawn from the cooling shaft 14 and from the spinneret 11 through a take-off godet 16. The thread wraps around the withdrawal godet 16 several times. The purpose of this is an overflow roller 17 arranged in an interlaced manner to the godet 16. The overflow roller 17 is freely rotatable. The godet 16 is driven by godet motor 18 and frequency generator 23 at a presettable speed. This take-off speed is many times higher than the natural exit speed of the filaments 12 from the spinneret 11 and higher than the filament speed after solidification in the pristine.

Only for the embodiment according to FIG. 2:

The thread is withdrawn from the cooling shaft 14 and from the spinneret 11 through a Abzunggalette 54. The thread wraps around the withdrawal godet 54 several times. The purpose of this is an overflow roller 55 arranged in an interlaced manner to the godet 54. The overflow roller 55 is freely rotatable. The godet 55 is withdrawn by a godet motor at a presettable speed. This take-off speed is many times higher than the natural exit speed of the filaments 12 from the spinneret. From the withdrawal godet 54, the thread passes through the heating device 20b to the further godet 16, which is referred to herein as the drawing godet. The draw godet 16 is driven at a higher speed than the previously described godet 54. As a result, the thread between the two godets 54 and 16 is stretched.

For both versions applies again:

From the draw godet 16 in FIG. 2 and the draw godet 16 in FIG. 1, the yarn 1 passes to the so-called "head thread guide" 25 and from there into the traversing triangle 26. In FIG. 1, the traversing device 27 is not shown. These are oppositely rotating wings, the thread 1 over the length of the coil 33 back and forth. In this case, the thread wraps behind the traversing device 27, a contact roller 28. The contact roller 28 rests on the surface of the coil 33 at. It is used to measure the surface speed of the coil 33. The coil 33 is formed on a sleeve 35. The sleeve 35 is clamped on a winding spindle 34. The spindle 34 is driven by the spindle motor 36 and spindle control 37 so that the surface speed of the coil 33 remains constant. For this purpose, the speed of the freely rotatable contact roller 28 is scanned on the contact roller shaft 29 by means of a ferromagnetic insert 30 and a magnetic encoder 31 as a controlled variable.

It should be noted that the traversing device 27 may also be a conventional Kehrgewindewalze with a in the Kehrgewindenut over the traversing area reciprocating traversing yarn guide.

In FIG. 1, the diameter of the coil 33 is continuously detected as a state parameter or a variable derived from the diameter. To measure the diameter, the rotational speed of the spindle 34 and the rotational speed of the contact roller 28, which rests on the surface of the coil measured. Ferromagnetic inserts 30, 38 serve in the spindle 34 as well as the contact roller 28 and corresponding pulse generators 31, 39. While the rotational speed of the contact roller 28 serves as a control variable for the adjustment of the spindle motor 36 via spindle control 37, the rotational speed of the spindle 34 what is not discussed here, related to the control of the traversing device 27.

As the embodiment of FIG. 1 shows, 16 stretching pins 56 and a heater 20 b lie between the cooling shaft 14 and the godet godet. The last of the draw pins 56 has a heated heating surface 32. The draw pins are preferably not rotatable and preferably fixed. They are partially wrapped by the thread. By adjusting the first pin perpendicular to the yarn path, the wrap angle and thus the contact length on the surfaces of each pin can be reduced or enlarged in the desired manner. In the case of an arrangement of three draw pins (FIG. 5), the middle draw pin is preferably adjusted. In Fig. 1, 4 and 5, the offset is exaggerated. In fact, a small offset is sufficient. At least one of the draw pins, preferably the last, is - as I said - heated. The temperature to which the filament is heated is higher than the glass transition temperature of the filament, which is 55 and below 120 ° C for polyester.

With a surface temperature of the heating surface 32 of the heated draw pin 56, which is above the melting temperature of the thread material, take-off speeds of up to more than 5,000 m / min are achieved. In this case, driving is carried out with very short contact lengths on the stretching pins 56.

In the embodiment of FIG. 2, the heater 20b is located between the godet godet 54 and the godet godet 16. In this embodiment, the surface 32 of the godet godet 54 is heated so that the draw point of the yarn forms immediately behind or on the godet. For further heat treatment, the thread is passed through the heater 20b.

Fig. 4 shows a modification of the embodiment of FIG. 2. Here, the withdrawal godet 54 is not heated. Instead, there are stretching pins 56 in front of the heating device 20b, of which at least one has a heated heating surface 32. Otherwise, these stretching pins correspond in their design and temperature control to the stretching pins which have been described in connection with FIG.

An advantageous development of the arrangement of FIG. 4 is given when the stretching pins 56 are arranged in the thread inlet region of the heating device 20b. The draw point of the thread will form immediately behind the last draw pin 56, so that the stretching and fixing takes place in the immediately following heat treatment.

Fig. 5 also shows a modification of the embodiment of Fig. 2. The withdrawal godet 54 is not heated. In front of the heater 20b, the unheated draw pins 56 are arranged. Opposite the wrap of the middle draw pin is a heated plate 58, so that both the thread and indirectly the draw pins are heated.

In this embodiment, the method is modifiable to the effect that the draw pins 56 can be omitted. The thread is then passed over the heated plate 58 with little contact or without contact.

In the embodiments according to FIGS. 4 and 5, which in each case replace the bordered part according to FIG. 2, are stretching pins and heating means - in this regard, reference is made to FIG. 1 - between withdrawal godet 54 and drawing godet 16.

In the embodiment according to FIG. 2, the withdrawal godet 54 is heated to a temperature in the range between 70 and 120 °.

In both cases, the withdrawal godets 16 may be heated at a temperature of about 150 ° ± 40 ° C to achieve a shrinkage and heat fixation of the thread. However, this is not the subject of the invention.

In the modification shown in Fig. 6, the thread is taken up galettly at a take-off speed of more than 5,000 m / min directly from the winding shown by the contact roller 28 and the spool 33. The stretching starts already in the spinning zone. The first stage of the heat treatment is formed by the entrained spin heat. The leadership of the thread over a curved surface can be omitted. The thread is then passed through an eyelet or thread guide 8 to the second stage of the heat treatment by means of the heater 20b. The heat treatment takes place in that the thread 1 is guided essentially over the heating surface 117. The heating surface 117 has a surface temperature that is above the melting temperature of the thread material. After stretching, the thread is wound directly onto the spool 33. With this modification, take-off speeds in the range between 6,000 to 7,500 mm / min can be achieved.

The heater 20b may be formed in two stages, with both stages of approximately the same length, i. Are 300 to 500 mm long or deliberately short in the feeder and longer in the following zones, so that a strong increase of the intake temperature compared to the following zones is possible. The temperature control is done so that in the input-side stage, the surface temperature is 450 to 550 ° C and in the output side stage, the surface temperature is 400 to 500 ° C. The thread is guided at a small distance to the respective surface, for example at a distance of 0.5 to 3.5 mm.

The heater 20b will be described with reference to FIG.

As shown, the heating device 20b may consist of several, here two track sections 114a and 114b lying one behind the other in the thread running direction. These are of different length, but otherwise the same cross-sectional shape. The purpose of such a two-part arrangement may be to heat the heater 20b differently in different length ranges in order to treat the thread 1 at a heat profile that satisfies its properties. This means that more than the two sections shown can be used. It is of particular importance that the angle formed by the two heating rails 114 to each other, is set identically at each processing point of the spinning-stretching machine, so that threads of the same quality are produced on all processing points. For fixing the two heating rails 114 is a mounting rail 158. This is a rail that has the length of the two heating rails. The mounting rail has a U-shaped cross section. The heating rails 114 are secured to the bottom of the mounting rail with spacers 160. By dimensioning the spacers and their position relative to the heating rail 114, the inclination of the heating rail 114 with respect to the straightened Fixed mounting rail 158. In this case, the two heating rails 114 with respect to the mounting rail opposite slope and form together an obtuse angle. The mounting rail 158 thus serves for a precise attachment of the two heating rails. Since the mounting rail 158 has a U-shaped profile, but it also surrounds the two heating rails. Therefore, the mounting rail 158 also serves the temperature equalization over the length and width of the heating rails. The mounting rail is surrounded by insulation.

It can be provided rod-shaped spacers 140, the longitudinal groove 112. Nutengrund, d. H. bridge the heating surface 117 and set the yarn path at an exact distance from the bottom of the groove. Alternatively or additionally, some or all yarn guides 132 with a circumferential leading edge, for. B. a circumferential groove 142 (Fig. 3a) may be provided, the height of the groove bottom is tuned with the predetermined by the guide bodies 140 height of the thread path. In this way, the thread, which is guided in the groove, additionally guided by the side edges of the groove. The circumferential grooves have the same depth over the circumference, so they are concentric with the yarn guides 132. However, it is also possible to form the circumferential grooves with varying in the course of the circumference depth, z. B. in that the groove bottom is indeed circular cylindrical but eccentric to the thread guides 132 is cut. In this case, the possibility of a fine adjustment of the contact between the thread 131 and thread guides 132 and the zigzag threadline is given by turning the thread guide. For this purpose, the yarn guides 132 could, for example, via a connecting linkage (not shown) rotate together and to the same extent.

Moreover, the heater is housed in an insulating box (not shown) in which it is in a heat-insulating material, eg

Glass fibers, embedded. The insulating box can be provided with a flap that allows it to open to provide access to the heater and insert the thread. Furthermore, the insulating box with its laying over the heater parts for axially fixing the yarn guide 132 in the rail 114. In this case, the insulating box is provided with slots that are aligned with the center plane and bevels 134 of the yarn guide 132 and allow it to be treated Insert thread 138 between the thread guides 132. The slots are provided on their side walls with wear-resistant insulating.

Also for. the heating elements 124, 126 necessary electrical contacts are optionally housed in the insulating box 144.

The contact surfaces with which the yarn guides touch the yarn have a relatively large diameter. In contrast, has the zigzag line, in which the thread is guided by the overlap U of the successive yarn guide, a relatively small amplitude, at a relatively large distance (A) between two adjacent yarn guides. This ensures that the wrap angle at which the thread wraps around the thread guides or the contact surfaces formed on them, even in the sum is small.

The heating rail has on its side remote from the longitudinal groove 112 side two grooves which lie substantially below the thread guide grooves 112. In these grooves heating elements 124 and 126 are inserted. The heating elements are clamped by a mounting rail 159, which extends over the entire length of the heating rail. For this purpose also has the mounting plate grooves, which surround the heating elements 124, 126. By loosening the mounting plate 159, the heating elements 124, 126 can be easily replaced.

The distance of the thread to the heating surface 117 is very small. The distance is in the range between 0.5 to 5 mm. Preferably, the upper value is not more than 3.5 mm in order to achieve a good heat transfer and an accurate trouble-free temperature control.
This results in the correspondingly high temperature of the heating rail of more than 350 ° C shock-like heating. The yarn guides 132 may be at least partially omitted or removed if they have a negative influence. On the one hand, they contribute to calming the yarn path and heating of the yarn by running contact and, on the other hand, have only a slight friction on the yarn as a result of the low looping.
The essence, however, is the non-contact guide in close proximity to the highly heated heating surface.

LIST OF REFERENCE NUMBERS

1

thread

2

filling

3

extruder

4

engine

5

heater

6

melt line

7

pressure sensor

8th

thread guides

9

Pump, gear pump

10

Spinning head. spin box

11

Nozzle, spinneret

12

Filaments, filament strand

13

Preparation roller, preparation device

14

cooling shaft

15

Injection, airflow

16

godet

17

Guide roll

18

drive motor

19

casing

20

heater

21

exit lock

22

frequency generator

23

frother

24

thread channel

25

Head thread guide, thread guide

26

Traversing triangle

27

Traversing device

28

contact roller

29

Contact roller shaft

30

ferromagnetic insert

31

pulse

32

Heating surface, surface

33

Kitchen sink

34

spindle

35

winding tube

36

drive motor

37

spindle control

38

ferromagnetic insert

39

pulse

40

entry lock

41

vapor channel

42

Heizdampferzeuger

44

pump motor

45

pump control

46

computer unit

47

water nozzle

48

Overflow body

49

extruder control

50

heating control

51

cooling control

52

exit lock

53

entry lock

54

Galette

55

Guide roll

56

draw pin

58

plate

112

longitudinal groove

114

rail

116

lower part

117

heating surface

118

wall

120

partition wall

122

wall

124

heating element

126

heating element

128

recess

130

slot

132

Thread guide, guide body

134

bevel

136

groove

140

Thread guide, spacers

142

circumferential groove

158

mounting rail

159

mounting plate

160

spacer

Claims (29)

1. Method for spinning, drafting and winding a multifilament synthetic thread (1), in which the thread (1), during drafting in a drafting zone, is subjected to multi-stage heat treatment by heated heating surfaces (32, 117), and in which the first heat treatment serves for heating the thread (1) to the region of the glass transition temperature of the thread material, the thread (1) being guided with partial looping (galette, plate or drafting pin) over a heating surface (32), and in which, immediately thereafter, the thread (1) is guided, in the second stage, along an elongate heating surface (117), characterized in that the surface temperature of at least one of the heating surfaces (32, 117) is higher than the melting temperature of the thread material, preferably higher than 100 Kelvin above the melting temperature of the thread material, preferably between 200 and 300 Kelvin above the melting temperature of the thread material, and in that the thread (1) is subjected in the drafting zone to a thread tension force which is required for plastic deformation in or directly downstream of the first stage of heat treatment.
2. Method according to Claim 1, characterized in that the thread tension force is essentially constant within the drafting zone.
3. Method according to Claim 1, characterized in that the thread tension force is increased within the drafting zone.
4. Method according to one of Claims 1 to 3, characterized in that the surface temperature of the first heating surface (32) is higher than the melting temperature of the thread material.
5. Method according to one of Claims 1 to 4, characterized in that the surface temperature of the second heating surface (117) is higher than the melting temperature of the thread material.
6. Method according to Claim 5, characterized in that the thread (1) is guided along the second heating surface (117) at a distance and essentially without contact.
7. Method according to Claim 6, characterized in that the thread (1) is guided along the second heating surface (117) by one or more short guide bodies (132) which are distributed along the heating zone.
8. Method according to one of Claims 2, 4 to 7, characterized in that drafting takes place between two galettes (54, 16) and the first of the galettes (54) is unheated, and in that the first stage of heat treatment takes place downstream of the first galette (54) by means of a fixed drafting pin (56) which the thread (1) partly loops around or at least touches.
9. Method according to Claim 8, characterized in that the first stage of heat treatment takes place downstream of the first galette (54) by means of a heated plate (58) along which the thread (1) is guided contactlessly.
10. Method according to one of Claims 3 to 7, characterized in that drafting takes place between two galettes (54, 16) and, for carrying out the first stage of heat treatment, the first of the galettes (54) is heated at a temperature in the region of the glass transition temperature of the respective polymer, preferably at a temperature of between 60 and 120°C.
11. Method according to one of Claims 3 to 7, characterized in that drafting commences in the spinning zone, the take-up speed of the winding lying above 5000 m/min.
12. Method according to one of the preceding claims, characterized in that drafting takes place by means of a galette (16) which takes up the freshly spun thread directly at a high speed of more than 3500 m/min from the spinneret, and in that the first stage of heat treatment takes place by means of a fixed drafting pin (56) which the thread partly loops around or at least touches.
13. Method according to Claim 12, characterized in that the first stage of heat treatment takes place by means of a fixed plate (58), along which the thread is guided contactlessly.
14. Method according to Claim 8 or 12, characterized in that the first stage of heat treatment is formed by a drafting pin (56), the drafting pin being arranged directly at the thread entry within an elongate heating surface (117), and the heating surface temperature being higher than the melting temperature of the thread material.
15. Method according to one of the preceding claims, characterized in that the synthetic thread consists of polyester, in particular polyethylene terephthalate.
16. Method according to one of Claims 1 to 13, characterized in that the synthetic thread consists of a polyamide (PA 6 or PA 6.6 or a blend of PA types).
17. Method according to one of Claims 1 to 13, characterized in that the synthetic thread consists of a polypropylene.
18. Method according to one of Claims 1 to 13, characterized in that the synthetic thread consists of a polytrimethyleneterephthalate.
19. Spinning, drafting and winding machine for spinning, drafting and winding a multifilament synthetic thread (1), in which the thread (1) is heated in the drafting zone by means of a heating device (20) in a plurality of stages with a thread tension force leading to plastic deformation, characterized in that the heating device (20a) of the first stage is a preferably curved heating surface (32) of which the thread (1) is guided, and in that the heating device (20b) of the second stage is an elongate heating surface (117) with thread guides (132), by means of which the thread (1) is guided contactlessly but in close proximity to the heating surface (117), and in that at least one of the heating surfaces (32, 117) is set at a temperature which is higher than the melting temperature of the thread material, preferably higher than 100 Kelvin above the melting temperature of the thread material, preferably more than 150 Kelvin above the melting temperature of the thread material.
20. Device according to Claim 19, characterized in that the heating device (20a) of the first stage of heating is set at a higher temperature than the melting temperature of the thread material.
21. Device according to Claim 19 or 20, characterized in that the heating device (20b) of the second stage of heating is set at a higher temperature than the melting temperature of the thread.
22. Device according to one of Claims 19 to 21, characterized in that the heating device (20) is formed by an elongate U-shaped or V-shaped rail, in the longitudinal groove of which the thread is guided in an essentially contact-free manner.
23. Device according to either one of Claims 19 and 21, characterized in that the heating device (20b) of the second stage is divided in two and is formed from two elongate U-shaped or V-shaped rails (114) which form an obtuse angle between them, and in that thread guides (132) are arranged in the region of the adjacent ends between the two rails (114) and serve for guiding the thread (1) in the longitudinal groove (112) of the two rails (114) in an essentially contact-free manner.
24. Device according to either one of Claims 22 and 23, characterized in that the thread (1) is guided along the heating surface (117) by one or more short guide bodies (132, 140) which are distributed along the heating zone.
25. Device according to one of Claims 20 to 24, characterized in that the heating device (20a) of the first stage is a heated drafting pin (56), around which the thread (1) is guided with partial looping, and in that the heating surface (32) of the drafting pin is set at a temperature higher than the melting temperature of the thread material, preferably higher than 150 Kelvin above the melting temperature of the thread material.
26. Device according to one of Claims 20 to 24, characterized in that the heating device (20a) of the first stage is a heated plate (58), past which the thread (1) is guided contactlessly, and in that the heating surface of the plate is set at a temperature higher than the melting temperature of the thread material, preferably higher than 150 Kelvin above the melting temperature of the thread material.
27. Device according to either one of Claims 25 and 26, characterized in that the drafting zone directly follows the spinning zone, without a take-up device, galette or the like being interposed.
28. Device according to either one of Claims 25 and 26, characterized in that the drafting zone is arranged between a take-up device, galette (54) or the like and a galette (16).
29. Device according to one of Claims 21 to 24, characterized in that the thread (1) is taken up by a take-up device, galette (54) or the like from the spinning zone and is conveyed into the drafting zone, and in that the take-up device is heated as the first stage of heat treatment.

Images