JPS6132411B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a heat treatment method in which thermoplastic multifilaments are introduced at high speed into a residence chamber, the filaments are heated in the form of a pack by a heating medium, and then treated by a gas flow through a treatment chamber. The present invention relates to a method and apparatus for crimping a plastic multifilament.

Known crimping devices for thermoplastic multifilaments have a retention chamber into which one or more filaments are fed at high speed by means of a feeding device and are formed into a filament pack and thereby crimped. Textile and industrial filaments from 40 to 3000 deniers are processed. The essential problem of this crimp method lies in the heat treatment of the filament, which is a heating and cooling treatment to fix the crimp. "Heat treatment" as used in this specification includes not only heat treatment but also cooling treatment.

The known crimping device (see German Patent Publication No. 12 45 912) has a treatment chamber through which the filament pack formed in the retention chamber passes for heat treatment. In this case, the filament pack rests entirely against the walls of the processing chamber, and the processing medium (hot or cold air) flows through it approximately perpendicular to the direction of feed of the filament pack. In this case, it is particularly undesirable for the filaments on the outside of the filament pack to come into contact with the walls of the processing chamber. Contact will result in non-uniform heat treatment over the length of the filament. Furthermore, important disadvantages arise due to compression of the filament pack by the walls of the processing chamber. That is, the heat treatment causes the filament and the filament pack to shrink, so that the treatment medium does not flow through the filament pack and instead flows around it, or the filament pack swells, increasing its density and disadvantageously reducing the gas permeability of the filament pack. .

The object of the invention is to form a filament pack in a residence chamber whose density and residence time can be controlled in the residence chamber and in a subsequent heat treatment zone;
It is also an object of the present invention to provide a crimping method and apparatus of the above type that can perform effective and uniform heat treatment in a treatment zone.

The object of the invention is to sandwich the filament pack at the outlet of the retention chamber between roller gaps suitable for hooping the filament pack of a set of supply rollers.
It is withdrawn at a speed V2 which is significantly lower than the introduction speed V1 and is fed into a gas-permeable guide channel adapted to the cross-section of the filament pack, generating a gas flow perpendicular to the running direction of the filament pack, which permeates through the filament pack. and is pressed against the guide channel, and the filament is withdrawn by a withdrawal device at the outlet end of the gas-permeable guide channel with a speed V3 significantly greater than V2 and approximately equal to V1. resolved.

A feature of the device of the present invention for carrying out this method is that a set of supply rollers is arranged behind the retention chamber, and this roller has grooves on its outer periphery that are suitable for the cross section of the retention chamber, and the grooves are parallel to each other. A processing tube is arranged to form a passage having a size less than or equal to the cross section of the chamber, and is arranged behind the supply roller, and this tube has a guide passage for the filament pack on its outer periphery, and the bottom of this passage is gas permeable. The cross section of the passage approximately corresponds to a segment of the cross section of the retention chamber, and the inside of the processing tube, which is airtight except for the bottom of the passage, is connected to the suction device.

An advantage of the present invention is that although heat treatment of the filament pack requires low processing speeds due to the pack density and relatively large cross-section of the filament pack, the filament pack is not laterally restricted by the processing chamber in the heat treatment zone and therefore The reason is that it can expand freely. The method of the invention is based on the surprising possibility that filament packs can also be fed without lateral restrictions. Furthermore, the invention has the advantage that significantly lower mechanical outlays are required for the heat treatment than with known crimping devices. In the case of known devices, the production of a treatment chamber that is gas-permeable and at the same time has very smooth walls requires high costs. Furthermore, a filament pack with unrestricted sides is advantageous because it can freely shrink or swell under the action of the heat treatment medium and the density of the pack can be controlled by the sporadic filaments and the speed applied to the filament pack.

Next, the present invention will be explained with reference to the drawings.

In FIG. 1, monofilaments 2 are spun from a spinning chamber 1 and assembled into one multifilament. The monofilament is taken off from the spinning chamber 1 in a gullet 4 at a constant speed, guided after the gullet 4 via a heating device 5 and then captured in a drawing gullet 6. Gullets 4 and 6 are driven at different speeds so that the filament is drawn between these gullets in a known manner.

Behind the gullet 6, the filament is fed to the processing nozzle 9 at a speed V1. The filament is exposed to hot gas or steam in the processing nozzle 9,
A filament pack 12 is formed in the residence chamber 10, which leaves the residence chamber at a constant velocity V2.
The supply of filament packs is carried out by supply rollers 11. The peripheral speed of the average diameter of the supply roller is V
It is 2.

Filament pack 1 behind supply roller 11
2 is fed into a linear guide channel running along the wall of the tube 13. The guide passage is gas permeable and the tube 13
is connected to the suction device 22. The filament pack is held and cooled or optionally heated in the guide channel by means of a suctioned air or gas stream;
The gas flow then passes through the walls of the guide channel. The filament is then taken off by take-off rolls 14 at a speed V3 so as to unpack the filament. The filament is attached to a chainient device 17 on a spool 18 driven by a drive roll 19.
It is wound up through.

Details of the crimping device are shown in FIGS. 2 and 3.

For example, hot air or other hot gas or heated steam is sent to the crimping nozzle 9 from a supply pipe 21 . Heating of the gas is performed by a heating device 23. The supply pipe 21 opens into a ring passage 25 . This ring channel 25 is connected to a filament guide channel 27 via a channel 26 delimited by a conical surface.

Retention chamber 1 to processing nozzle 9 concentrically with guide passage 27
0 connects. The residence chamber has a slit 28 in its wall, through which the air or gas or vapor entering the residence chamber 10 from the nozzle 9 escapes.

The medium fed into the retention chamber forms a filament pack in the retention chamber with the same diameter as this chamber, the heated filament being crimped.

A supply roller 11 is arranged next to the retention chamber. This supply roller is driven at one constant circumferential speed, that is, at an average circumferential speed V2. The supply rollers 11 create a gap between the pair of rollers suitable for the cross-section of the filament pack, at which point the filament pack leaves the retention chamber. For this purpose, the supply roller 11 is provided with a groove having a substantially semicircular cross section on its periphery. The supply roller can also be provided with projections on its cylindrical surface, such as needles or fins 29, which engage the filament pack, as shown in FIG.

The filament pack 12 is fed into the guide channel 24 by the feed roller 11. The guide passage 24, shown in cross section in FIG. 3, is formed by a recess in the processing tube 13. The bottom of the recess has a slit 28 leading into the interior of the processing tube 13. The slit 28 extends from a point 30 at the entrance of the processing tube 13 immediately after the supply roller 11 to a point 31 just before the exit end of the processing tube 13.

The processing tube 13 is completely hermetically closed up to the slit 28 and is connected via a connecting tube 22 to a suction device (not shown). As a result, a gas or air flow 32 is created in the filament pack in the region of the recess approximately perpendicular to the direction of travel of the pack.

This gas flow 32 serves two functions: The filament pack 12 provides resistance to this gas flow. The gas flow thereby serves to keep the filament pack adhered also to the vertically arranged tubes. Furthermore, a gas stream flows through the filament pack, thereby effecting the heat treatment, in particular the cooling.

It is also an embodiment of the present invention to cool the filament pack by drawing indoor air. The process tube 13 or other gas-permeable guide channel is surrounded by a substantially closed vessel on the side of the guide channel, which vessel is filled with a medium other than room air, such as air enriched with water mist, heated or saturated steam, heat It is also within the scope of the invention if these gases flow through the filament pack due to pressure on the side of the running surface of the filament pack or under reduced pressure on the side opposite the running surface of the guide channel. It is likewise possible to carry out different heat treatments over the length of the guide channel.

After the heat treatment has been carried out in the treatment tube 13, the filament is taken off by a taking-off device 14 (for example, a set of rolls) at one constant speed V3.

Adjustment of the various speeds V1 to V3 of the filament or filament pack has a great influence on the product obtained.

For this reason, the main drive 7 is connected to the supply elements of the crimper (gallets 4, 6; supply rollers 11; take-off device 14; drive rollers 19) and the transmissions 8, 15, 16.
and 20.

The transmission 8 is adjusted by the stretching rate. The transmission 15 that adjusts the circumferential speed V2 of the supply roller 11 is empirically determined by the following formula: V2/V1=1.42・10 ^-4・den/P・γ・D ² [Here, V1 is the circumferential speed of the galette 6, in other words Then, the speed at which the filament is fed to the processing nozzle 9, den is the fineness in g/9000m, and γ is the specific gravity kg/dm ³ , D
is the diameter of the retention chamber in mm. ] is adjusted to satisfy. Pack density P is a factor of integrity and is used as a measure of the density of the filament pack formed in the residence chamber. The pack density of the filament pack in the residence chamber is dependent on the flow rate and temperature of the processing medium, in particular the heated air. There is a relationship between the pack density and the crimp achieved; there is a general tendency for higher pack densities to produce stronger crimp. However, a large pack density also increases the resistance of the gas flowing through the filament pack for heat treatment. With increasing pack density, there therefore arises the risk of non-uniform heat treatment over the cross section of the filament pack.

Due to the increased resistance due to the increase in the density of the filament pack, the compression and friction in the guide path of the filament pack becomes high, the stagnation becomes longer and the pack density increases again, and the process becomes unstable.

To avoid this drawback, the circumferential speed V of the supply roller 11 is
2 needs to be carefully adjusted. This is because the pack density can thereby be effectively controlled without significantly affecting the crimping result, as is clear from the above equation. If the peripheral speed V2 is low, the pack density will be high, and if the peripheral speed V2 is high, the pack density will be low. In order to adjust the crimping device, the optimal pack density from the textile industry and process technology point of view is determined by experiment, and this pack density is then used in industrial production by adjusting the circumferential speed V2 according to the above formula. It is necessary to.

The filament velocity V generated by the take-off machine 14
3 is significantly greater than the feeding speed of the filament pack or the circumferential speed V2 of the feeding roller. V3 is approximately equal to V1, but as small as required by the crimp or other crimp properties achieved.

In any case, V3 is selected at such a height that the filament pack is unwound at the outlet of the processing tube or guide channel 24. On the other hand, the filament speed V3 must be adjusted so that the filament pack unwinding position does not fall within the range of the slit 28 between points 30 and 31 and does not move.

With the device of the invention, the packing density can be adjusted independently of the working parameters in the retention chamber, which can only be varied within limits, since they have a lasting influence on the deformation of the filament in the retention chamber and thus on the crimping result, and independently of the working parameters in the retention chamber. This can be controlled by a simple mechanical adjustment of the transmission 15, regardless of the friction occurring between the gear and the pack.

As is clear from the foregoing description, the advantage of the present crimping device is, inter alia, that the tension-free heat treatment of yarns is possible without the risk of operational difficulties that arise in the treatment of tension-free filaments, especially at high production speeds; At the same time, the various speed control and heat treatment methods make it possible to finely adapt the process to the textile and process-technical requirements of crimping.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing an outline of a continuous spinning, drawing, and crimping device according to the present invention, Fig. 2 is a longitudinal sectional view of the crimping device, Fig. 3 is a cross-sectional view of a filament processing tube, and Fig. 4 is a diagram showing an outline of a continuous spinning, drawing, and crimping device according to the present invention. FIG. 7 is a longitudinal cross-sectional view of another embodiment of the supply roller. DESCRIPTION OF SYMBOLS 1... Spinning chamber, 2... Monofilament, 3... Multifilament, 4, 6... Galette, 9... Processing nozzle, 10... Retention chamber, 11... Supply roller, 12...
Filament pack, 13...processing tube, 14...take-up roll.

Claims (1)

[Claims] 1. A method for crimping the thermoplastic multifilament by introducing a thermoplastic multifilament into a retention chamber at a speed V1 and forming the filament into a pack, in which a filament pack 12 is inserted into the retention chamber 10.
At the exit of the filament pack 12, the filament pack is sandwiched between a pair of supply rollers 11 in a roller gap suitable for circling the filament pack, drawn out at a speed V2 significantly lower than the introduction speed V1, and fed into a gas-permeable guide passage 24 suitable for the cross-section of the filament pack 12. , a gas flow 32 is generated perpendicular to the running direction of the filament pack, which gas flow passes through the filament pack 12 and presses against the guide channel 24, so that the filament is removed at the outlet end of the gas-permeable guide channel 24 by a withdrawal device. 14. A method for crimping a multifilament, characterized in that the multifilament is drawn at a speed V3 significantly greater than V2 and approximately equal to V1. 2 The supply roller 11 is driven at a circumferential speed of V2, at which time the following formula: V2/V1=1.42・10 ^-4・den/P・γ・D ² [V1 is the speed at which the filament enters the retention chamber, den is The fineness of the filament is g/9000m, γ is the specific gravity of the filament Kg/dm ³ , D is the diameter of the retention chamber, P is the pack density of the filament pack, and P<1]
The method according to claim 1, which satisfies the speed ratio condition of: 3 In an apparatus for introducing a thermoplastic filament into a retention chamber at high speed, forming the filament into a pack, and crimping a thermoplastic multifilament, a set of supply rollers 11 is installed at the rear of the retention chamber 10.
are arranged, the rollers have grooves on their outer peripheries that are suitable for the cross section of the retention chamber 10, and are arranged parallel to each other so that the grooves form a passage having a size smaller than the cross section of the retention chamber 10, and the supply roller 11 Processing tube 1 behind
3 is arranged, this tube has a filament pack guide passage 24 on its outer periphery, the bottom of this passage is gas permeable, the cross section of the passage approximately corresponds to a segment of the cross section of the retention chamber, and the passage is airtight except for the bottom. processing tube 13
A device for crimping multifilament, characterized in that the inside of the device is connected to a suction device.