DE854690C - Method and device for the production of artificial threads dried in the form of a thread sheet - Google Patents

Description

(WiGBl. P. 175)

ISSUED NOVEMBER 6, 1952

A4664 FII / 2p a

When producing artificial threads using the wet spinning process, ζ. B. made of viscose, has already been proposed that washed and post-treated threads together in the form of a thread sheet dry.

For this purpose one led the thread sheet, in which the individual threads at a distance of about 4 to 10 mm apart, mostly via one or more series-connected Drying drums or drying rollers.

However, drying rollers of this type are uncomfortable when drying severely swollen threads Appearances in these threads. In this way, the threads can be flattened in the form of a ribbon while drying and when the threads are dried in this state, the end product becomes undesirable Properties. As a result of the tension with which the threads are guided over the rollers, they get these threads hardly have an opportunity to shrink. This disadvantage also remains ao stand when the circumferential speed of the rollers connected in series is mutually regulated, d. H. the peripheral speed of successive rollers is reduced.

It has also already been suggested to use hot air to seal artificial silk as thread sheets in the open slope dry.

The methods and devices used up to now have the particular difficulties which occur when drying layers of artificial silk thread, only partially overcome.

It is Z. B. known for this purpose simple, lidded horizontal drying boxes to use, through which the thread sheet in hori-

zontal direction and which boxes with heating pipes arranged under the thread sheet and fans are equipped. However, such drying devices have the disadvantage that the hot air cannot be distributed effectively enough, especially when the thread speed is high get a considerable length. In addition, the inclusion of a single thread in the thread sheet very difficult, so ίο more so when the number of threads in a thread sheet is great. With these devices it is also not possible to use the desiccant simultaneously and quickly to bring into contact with all threads.

According to the invention it has now been possible to develop a new method and a new device, which overcome the difficulties encountered up to now when drying sheets of thread, the invention also offers numerous and surprising advantages. The new procedure differs in that that the wet thread sheet is passed through a flat slit-shaped drying chamber, the dimensions of which correspond to the flat and thin thread sheet as much as possible, and that preheated air in the chamber is guided, preferably in countercurrent to the running direction of the thread sheet, while the air as it flows through the drying chamber in a direction opposite to the running direction of the threads Direction is also gradually reheated.

By adapting the slit-shaped flat drying chamber to the dimensions of the thread sheet on the one hand and guiding the drying air along the threads in countercurrent on the other hand a particularly intensive contact between the thread sheet and the dry air is achieved. The warming of the Air before it enters the drying chamber offers important advantages over this according to the invention the use of heating elements, such as heating pipes, to the extent that harmful when preheated Temperature differences in the air flow can be almost completely eliminated.

The gradual reheating and even a gradual increase in temperature of the dry air can be carried out according to the invention in such a way that one part between the stages the drying air from one zone is discharged from the drying tunnel and immediately thereafter as a stream of higher heated air supplies a subsequent zone of the drying tunnel.

However, it is also possible to use the air discharged from the drying tunnel in a specific zone outside of the channel to be heated higher and then to be fed to another zone.

By gradually increasing the air temperature in an opposite direction to the moving sheet of threads Direction it is on the one hand possible, the already partially dried and thereby for Overheating to protect sensitive thread sheet at the end of the drying chamber, while on the other hand is possible, the still wet, not particularly sensitive thread array in the first zones of the Treat the drying tunnel with highly heated air in order to increase the efficiency of the drying process the changing properties of the thread sheet during drying to be able to customize.

According to the invention, the drying can be accelerated and improved in that at least in the first zone of the drying tunnel, in which the thread sheet is still wet or not completely is dry, heat radiation is applied, which is so uniform over the width of the thread sheet should be directed as possible and perpendicular to the thread sheet. The thermal radiation is preferred used in the zone in which the thread sheet still contains a lot of water and of water vapor is surrounded. Next, the direct action of the rays on the threads and on the adhering ones Water, this radiation also increases the temperature of the dry air in these zones.

After the thread sheet has left the drying tunnel, it can be rearranged before it or conditioned before the winding or twisting of the individual threads.

The last zone of the drying tunnel can also be used for conditioning for this purpose. The new drying apparatus has the following features.

Their shape is adapted to that of the thread sheet, ie it corresponds to the threads lying in one plane and therefore has only a small height; it has a width corresponding to the width of the coulter, a bottom that can be folded down and support devices for the threads as well as devices for heating and forward movement of the hot drying air, if necessary conditioning air, which are provided outside the drying chamber, by means of which the air can pass through openings in the upper drying chamber. _lO o wall can be supplied and removed.

The bottom of the drying chamber as well as the level in which the threads in the drying chamber forward are moved, run approximately parallel to the floor surface. You don't need to be horizontal, however to run away.

The output of the chamber can e.g. B. be arranged lower than the entrance, so that Differences in level between successive devices for treating the thread sheet no can easily be bridged.

The operation of such a drying device with a hinged bottom is even with a large one Width of the thread sheet very light.

The supporting and guiding _{organs for n 5} the threads can be designed in various ways. However, it is advisable to design the support organs as a comb at the beginning and at the end of the drying chamber, which has interchangeable teeth, so that when breaking or cutting ζ. Β. A completely new comb does not need to be arranged on a tooth.

According to the invention, the support and guide members for the threads can be several perpendicular to the thread sheet, articulated

Form well-ordered combs, which are also folded down after opening the bottom can. The teeth of the comb are arranged close together and serve to the To keep threads at a certain mutual distance, with the chamber closed stand at an angle on the floor in such a way that the tips of the teeth are farther than their lower ends from the point of articulation are away.

ίο Due to the inclined arrangement, the threads get caught when introducing, while the combs are in the vertical position, not out of the combs. The latter are individually articulated, but they can just as easily be articulated together. The latter can be carried out in that all combs on a single, along the drying chamber extending shaft are arranged.

After opening the bottom and the combs, the rayon threads can easily be pulled in insert the combs, whereupon the same through an auxiliary roller set up behind the drying device be included. However, you can also close the thread sheet in front of the drying device unite a thread bundle and this bundle on an auxiliary roller behind the drying device run up, whereupon the threads are laid one after the other in the combs.

As soon as all threads are inserted, the same are secured by locking bars between the Kept combing. The combs are swiveled together with the thread sheet into the chamber, and on it the floor is folded up.

Now it starts with the ventilation set

Dry all threads at the same time and at once. The emerging dry thread sheet can now undergo further treatment; it can be reared up on the whole, or the threads can be wound individually or fed to a ring or bell twisting machine will.

According to the invention, the operation, monitoring, etc. of the drying chamber and thread bundle can be by the fact that the floor of the drying chamber is not made of a single piece, but is made of several, independently hinged parts.

In practice, the flat lower edges of the comb bridges can be used as sealing surfaces use for the bottom edges. It must then be ensured that the lower edge of the comb bridges in the folded-up position with the lower sealing surfaces of the longitudinal walls of the chamber comes to lie in one plane. The edge now comes to both ends of the drying chamber of a bottom part to lie on the relevant ridge bridge, while a ridge bridge is the same Time is used to seal two adjacent bottom part edges.

According to the invention, the devices for heating and circulating the air Arrange above the drying chamber. This ensures that the air supply into the drying chamber as well as their distribution over the entire cross-section of the chamber and their removal considerably be relieved. At the same time, the opening of the drying chamber floor is blocked and the combs in discontinuation.

In order to create different heating zones in the drying devices, input and Outlets for the air are provided at the transition points between the zones on the upper side of the drying chamber. So you can z. B. when drying in countercurrent, some of the air used the last Lead the zone via a radiator with a higher temperature into the penultimate zone, etc. The exhaust air the first drying zone can be discharged outside or for indirect preheating the fresh air can be used for the last zone.

Despite the constant absorption of water through the air, it is possible in this way to maintain its temperature to hold up and even to increase gradually.

In the event that the countercurrent principle and a drying chamber consisting of three zones are used, one can use this way, for. B. Adjust the first zone, in which the wet filaments occur at 150 ^0, the middle zone to 120 to ⁰ and the last zone, from which the yarn sheet comes out in dry state, to 8o ° C.

For heating and circulating the dry air and, if necessary, for circulating, temperature control and humidification of the conditioning air can be used already known devices. The fresh air and the air extracted from the drying chamber between the zones can be carried out by means of known apparatus prior to their supply or re-supply Steam or combustion gases are heated indirectly.

If necessary, metal plates are used as heat radiators, which are inserted into the upper wall of the Dry ducts can be installed, these plates according to the invention above by gas flames can be heated. The exhaust gases from these flames can be used as indirect heating for the Dry air serve both for the fresh air and for the air introduced between two zones.

A thread catching device at the entrance to the drying tunnel has proven to be particularly advantageous shown. As soon as a thread broke in the drying tunnel, it was the dry end of the thread pulled out of the drying chamber by the pull-off element, but the wet part remained lie. The air flow could, if it is opposite to the running direction of the threads, this Slide the wet end into a ball, which can then cause disruptions. A thread catcher At the entrance of the drying channel, however, the thread immediately pulls out of the channel before the thread causes any problems can.

For the purpose of easy implementation of the various treatments, the arrangement of Avoid supports directly under the drying chamber by placing the drying 1 * 5 The device hangs up, for which purpose racks are used

whose feet are as far apart as for easy access to the lower side of the Drying device is required.

By means of these drying devices, heavily swollen rayon threads, such as these z. B.

occur in the viscose rayon process, even at high take-off speeds of 60, 80, Dry well 100 m and more per minute.

By a precisely working feed device for the transport of the thread sheet to the drying device and by an automatic or manually adjustable, arranged behind the drying machine The thread tension can be adjusted with the puller. This makes it possible to shrink the filaments during the drying process.

Figs. 1 to 6 illustrate an embodiment

the device with two variants. The Fig. ι to 3 relate to the variant in which

ao none, and FIGS. 4 and 5 show the variant in which Find heat radiation body use.

Fig. Ι shows the closed device in the longitudinal direction;

Fig. 2 shows the associated section according to as the line AA;

Fig. 3 is a vertical longitudinal section through the device, showing the floor and the comb bridges are folded down with combs together with the thread sheet;

Fig. 4 is a vertical longitudinal section through the device provided with radiant panels, and Fig. 5 shows a vertical section along the line BB;

Fig. 6 is a side view of a comb bridge, a comb and a lock rod;

Fig. 7 is a side view of the comb bridge in the folded down position.

Referring to Figs. 1 to 3, 1 is a driven one Removal and feed system for the thread sheet 2, which is only illustrated in FIGS. 1 and 4 in a longitudinal view has been.

The feed device can consist of four horizontally arranged rollers, of which at least some may be driven. The rollers 3 and 4 form a pair of pressure rollers at the same time, to press water out of the threads, which relieves the load on the drying machine. The thread sheet goes through the gap-shaped drying chamber 5 over the back of the combs 6 (for the clarity of the Drawings shown only in Fig. 2), which are arranged on the comb bridges 22, and leads between the teeth 17 and 17 'through to the driven slip roller 7. Through pipes 8 is hot air is blown in and blown off through pipes 9 so that the air moves in one direction the threads move forward in the opposite direction. However, direct current is also possible. The comb bridges 22 are articulated.

The fold-down floor 11, which is composed of several parts is attached to the sites 13 rotatably on the pivot lever 12, which is connected at the pivots 14 with the frame \, so that the floor parts, self-adjusting, sealingly attached to the edges 15 and 16 of the drying tunnel. The teeth 17 and 17 'are arranged obliquely on the back of the comb 6 in such a way that the tooth tips are further away from the pivot point 10 than the lower ends. The end of the comb 6, which is furthest from the pivot point 10, terminates with the comb bridge 22 in a recess in the channel edge, so that when the bottom 11 is closed, each end of the comb bridge is sealed at the same time.

The channel is divided at the places where there is a ridge, and each channel part seals up the lower edge of the comb bridge 22, so that each channel part is independent of the other Channel parts is hinged.

In Fig. 3 you can see how the threads of the coulter 2 are distributed by means of the teeth 17 and 17 'and as when folding down the comb bridges, the thread sheet from the horizontal position into the vertical position Position comes without disturbing the grain.

The thread catching device is denoted by 28 in FIG. 1.

4 and 5 show how the radiation plates 18 are embedded in the upper wall of the drying tunnel 5 are which their heat rays immediately at a short distance on the thread sheet (not in Fig. 5) can be transferred and heated as through the tubes 19 with gas flames 20 will.

The exhaust gases are discharged upwards through the hood 21, possibly via a radiator to serve for the warming of the fresh air or the already used dry air coming through the tubes 8 is introduced into the drying chamber.

Fig. 6 illustrates the construction of the combs in detail. The ridge bridge 22 is pivotable about the joint 10. The threads of the thread sheet 2 run over the smooth back 23. There are two parallel rows of teeth, which are arranged in a zigzag shape and through which the threads of the thread sheet 2 are kept at a small distance from each other. The two Rows of teeth are so far from each other that after distribution of the threads through the teeth the securing rod 24 pivotable about the bolt 25 is pivoted between the two rows of teeth and can be attached. As a result, the thread sheet is in every position of the combs recorded unchanged. The rows of teeth 17 and 17 ', the guide back 23 and the safety rod 24 end, as shown in FIGS. 2 and 5, in the vicinity of the point 26 still within the drying chamber 5, so that the turned away from the pivot point Comb end only through the comb bridge 22, which is sealingly in the side wall of the drying tunnel 5 closes, is formed.

Between every two combs there can be smooth rods and 27 'perpendicular to the direction of the thread sheet be arranged, as illustrated in FIG. 4. The rods 27 are then on the upper part

of the channel 5 and the rods 27 'attached to the fold-down channel parts 11. The mentioned Rods are vertically adjustable so that they can possibly force the thread sheet into a zigzag shape to run away. This prevents the thread sheet 2 back and forth between two combs fluctuates and thereby comes into contact with the plates 18, whereby what is even greater It is important that the threads do not break due to vibration.

Claims (1)

Patent claims: i. \ ^A learn about the production of artificial threads, which are in the form of a thread array > S are dried, characterized in that the thread sheet leads through a drying chamber, the dimensions of which correspond to the external dimensions correspond to the flat thread sheet, while at the same time preheated air in the longitudinal direction, preferably in countercurrent, blows through the drying chamber, and with the drying air in one of the running directions of the threads in the opposite direction is gradually reheated. »5 2. The method according to claim i, characterized in that that at the transition from one temperature zone to the other a part of the dry air from one zone, which is further from the entrance of the drying device, is discharged and immediately afterwards a stream of higher heated air of the closest, closer to the entrance of the drying tunnel lying zone is fed. 3. The method according to claim 1 and 2, characterized in that the drying, at least in the first zones of the drying tunnel, in which the thread sheet is still moist, by thermal radiation is accelerated, which radiation is evenly distributed over the thread sheet, by standing perpendicular to it. 4. The method according to any one of claims 1 to 3, characterized in that the im Drying tunnel used and reheated drying air from zone to zone by exhaust gases from the Jet burner is heated indirectly. 5. Device for performing the method according to one of claims 1 to 4, characterized through a flat slit-shaped drying chamber, the bottom of which is hinged downwards can be opened, while support and guide elements are provided for the threads in the chamber, and those outside the drying chamber with means for heating and ventilating the drying air, the is guided in the chamber along the threads is provided. 6. Apparatus according to claim 5, characterized by support means for Artificial silk threads in the form of combs, which run perpendicular to the thread sheet, pivotable are fixed in the drying chamber and after opening the drying chamber floor can also be folded down, the mutual spacing of the teeth of this Combs is small and the teeth are arranged at an angle on the back of the combs, so that the tips of the teeth are further than their lower ends from the pivot point of the combs. 7. Device according to one of claims 5 or 6, characterized in that the combs are connected so that they can be folded down together. 8. Device according to one of claims 5 to 7, characterized in that the bottom the drying chamber consists of several hinged parts. 9. Device according to one of claims 5 to 8, characterized in that the comb bridges, on which the combs are provided, are formed at the two ends so that the folded-up bottom parts of the chamber when closing on the lower edges of these bridges close tightly. 10. Device according to one of claims 5 to 9, characterized in that the devices are provided for heating and supplying the air above the drying chamber. 11. Device according to one of claims 5 to 10, characterized in that the last Zone of the chamber is set up as a conditioning room for the dry thread sheet, in which Chamber part the moist conditioning air flows in the same direction as the thread run. 12. Device according to one of claims 5 to 11, characterized in that the Drying device at the entrance of the drying chamber with a thread catching device see is. 13. Device according to one of claims 5 to 12, characterized in that the drying device is suspended from a frame is, which is set up in such a way that no supports directly under the drying chamber are provided. 1 sheet of drawings © 5444 10.