US2892336A - Apparatus for wet-treating threads, particularly viscose rayon threads - Google Patents

Description

June 30, 1959 p so l A L2Y,892,336

2 Sheets-Sheet 1 APPARATUS FOR WET-TREATING THREADS, PARTICUL VISCOSE RAYON THREADS Filed Jan. v 51, 1955 INVENTOR: Ambrogiio Agnnt h 2 S 9 .r 8 t ,Y e m m m s U 2 C I June 1959 A. PENSOTTI APPARATUS FOR WET-TREATING THREADS, PART VISCOSE RAYON THREADS Flled Jan 51, 1955 INVENTOR: Ambg/ggia y ensolll't M Y IQ Agent l l l l i United States Patent 2,892,336 APPARATUS non WET-TREATING Trni jAos}, PARTICULARLY vrsc osn RAYON THREADS Ambrogio Pensotti, Busto Arsizio, Italy 1 Application January 31, 1955, Serial No. 4s's,1'7s Claims priority, application Italy February 2,1953

Claims. or; 68-19) The" present invention relates to the manufacture of artificial threads, particularly viscose rayon threads; and at providing an improved apparatus by which artificial yarn as it comes from the spinneret can be subjected to one or a number of wet treatments such as washing, desulphurizing, bleaching, dyeing, soaping and dressing, in a continuous manner. p

The methods at present known for treating such threads require rather cumbersome mechanisms' which take up' considerable space and are subject to the fur ther disadvantage that it is very diflicult toprevent undesired contact between the various treating fluids used when the same thread is subjected to a series of wet treatments. It is also difficult to manufacture reliable electric motors capable of running at the very high speeds required for driving the centrifugal spinning boxes ordinarily used for collecting the treated threads.

, The object of the present invention is to provide an improved apparatus for wet-treating artificial threads, which is compact, uses relatively few moving parts, and is completely reliable in operation. 7

The apparatus according to the invention includes upper and lower rotatable rollers for supporting a flat tened helicoidal run of the thread to be treated having ascending and descending portions, means forming a plurality of separate channels for receiving said ascending portions of said flattened helicoidal run of thread, and

means for feeding at least one treating fluid to at least one of said channels, the said channel having at least one transverse ridge or projection over which the fluid flows by gravity and by which it is brought into contact with the ascending thread. 7

The invention and its subsidiary features will be fully understood from the following more detailed descripion with reference to the accompanying drawing, which illustrates one example of a machine according to the invention, and in which:

Figure 1 is a diagram illustrating the flattened helicoidal form of thread path and showing three rollers by which a thread is supported in this path,

Figure 2 is a diagrammatic vertical sectional view showing the principal working parts of the apparatus for applying one treating fluid to a thread at one point,

Fig. 2a is a perspective fragmentary view of the chanhelled washing plate shown in Fig. 2,

Figure 3 is a fragmentary sectional view of a part of the apparatus shown in Figure 2,

, Figure 4 is a perspective view of a hatchel provided on the machine for controlling the operation of threading the machine,

. Figures 5 and 6 are a front elevation and vertical section respectively of the substantially complete machine,

Figure 7 is a reproduction of part of Figure 6 on a larger scale, and s Fig, 7a is a perspective view of a detail sho'whin Fig. 7, drawn to a larger scale.

In the machine shown in the drawing, a viscose mix ture, mi-tered by means of a gear pump 1, is propelled through a filter 2 and a platinum spinneret 3 into a coagulating bath B, where the cellulose present in the Viscose in liquid state coagulates and takes on a solid form in the usual way, freeing itself of the other substances which make up the viscose mixture. However, part of these substances continue to adhere to the cellulose, forming a rayon fiber. The thread is moved on towards a first glass roller 4, and from this it passes to a second roller 5, also of glass. The two rollers 4 and 5 are driven by means of the gear mechanism 6, 7 in such-a way that roller 5 has a higher peripheral velocity than the roller 4, so that the thread, which has only just been formed, undergoes permanent stretching suitably adapted to direct the component fibers along the axis of the thread, thus increasing its tenacity and reducing its elasticity. The yarn passes from the second roller 5 to a thread guide 8, which determines the exact point at whichthe yarn is fed to the upper roller 9 of a group ofthree rollers 9, 10 and 11 (see Figs. 1, 5 and 6), of which the upper and lower ones, 9 and 11, are relatively skew by having their axes slightly inclined to one another both vertically and horizontally so that a thread F, wound helicoidally on the two rollers, will advance along the length of the rollers with a pitch which is determined by the angle of relative inclination of the two rollers.

The intermediate roller 10 has its axis parallel to the lower roller 11 and serves to displace adjacent ascending portions of successive convolutions of a thread F wound on the drums 9 and 10, so that they all he in one plane. Supported behind this plane and parallel to it is a washing plate 12, serving as a guide means for the thread, the front surface of which is formed with a series of separate longitudinal channels 13, having transverse ridges or projections 14 which extend completely across the channels 13, over the side walls 15 of the channels and across the spaces between the channels as shown most clearly in Figures 2, 2a and 3. Owing to the V-shaped upper outline of the ridges each ridge has within the respective channel an edge which is lower than the edges of the side walls of the channels, so that the liquor may flow along the respective channel without overflowing to the adjacent channels. The plate 12 may have an internal space 16, in which hot water and steam may circulate, entering by means of an orifice 17 and flowing out through another orifice numbered 18, as shown by the arrows p (Fig. 2). The portions of thread extending between the rollers 10 and 11 are arranged to lie in the channels 13, the side walls 15 of which prevent movement of the thread portions from one channel to another. However, in order to enable the helicoidal winding to be formed in the initial threading of the machine the apparatus is fitted with two deflecting bars 19 and 19, which are mounted eccentrically on control shafts 20 and 20' respectively, and which are originally set in such positions as to support the threads in front of the plate in a plane spaced from the guide plate 12 as indicated at P in Figure 7. When the deflecting bars are in this position an auxiliary elastic belt (not shown) is mounted, only during the initial period, on the cylinders 9 and 11, in line with the guide 8. Owing to the relative inclination of the rollers, the rotation of the rollers causes the belt to move along the axis of the roller until it reaches the other extremity of the latter, the displacement being at a rate equal to the distance between successive convolutions of the helicoid for each complete revolution of the belt. The end of the thread coming from the rollers 4 and 5 is attached to this belt, and the thread therefore wraps itself round the rollers 9 and 11, the leading convolution formed at every revolution of the band obviously advancing along the cylinder through a distance equal to the spacing of the convolutions. As the thread F is free at the other end, a continuous helix will be formed on the rollers 9 and 11, until the yarn is completely threaded onto the whole length of the rollers 9 and 11. In order to ensure regular spacing of the convolutions of the thread on the rollers, the apparatus is equipped with a rotating hatchel 21 (Fig. 4) consisting of a shaft formed on one side with teeth extending part way round the shaft and on the other side with a flat face. This shaft is rotated by a suitable driving mechanism so that the teeth thereon move alternately into and out of engagement with the thread F. The intermittent disengagement of the teeth enables the endless belt used for threading the machine to advance along the length of the rollers and also permits the convolutions of thread immediately following it to move into position for correct engagement with the teeth of the hatchel which finally brings them to their correct positions along the length of the rollers. A hand device (not shown in the drawing) is provided by which the hatchel 21 can be disconnected from its driving mechanism when the threading process is completed and stopped in a position such that its teeth are in mesh with the thread convolutions. When this has been done the shafts 20 and 20' are rotated to retract the deflecting bars 19, and 19 thereby allowing the threads to take up their position in the channels 13 of the guide plate 12. The hatchel 21 may now be manually rotated to a position in which its teeth are out of engagement with the threads, since the latter are now guided by the channels 13.

The plate 12 is arranged so that there are no channels 13 for the first few convolutions of the winding, thus providing an initial length of path in which the thread is untreated suflicient to allow time for the coagulation process to be completed. A zone of coagulation is thus provided which is so regulated by adjustment of the linear speed of the thread and the length of its path through the zone as to allow the time necessary for completing the coagulation. After leaving this zone, the thread passes into the series of channels 13, which are subdivided into a number of zones in each of which a definite treatment or process takes place, channels belonging to different zones being fed with different solutions. In more detail, a group of pipes 22, partially enclosed in a main conduit 23, continuously feed separate collection and, at the same time, distribution tanks or receptacles, as in 24 of Figs. 2 and 7, each of which has a front wall 24' carrying a glass rod 25, bent in the form of an inverted J, the external extremity of which glass rod projects beyond the bottom of the tank or receptacle 24, terminating just above an inclined surface 12' of the plate 12, which leads to a channel 13. The liquid in the tank 24 creeps up the rod 25 by surface tension and is fed to the channel 13 beneath at the rate of a few drops per second, thus insuring a self-regulating feed of constant flow. As is shown in Fig. 2, the plate 12 is steeply inclined so that the liquids flow downwards over the ridges 14, whilst the thread F advances in the opposite direction. The thread makes contact with the tips of the ridges but is held away from the bottom of the channel. Consequently, as the thread passes over the first ridge, it imbibes liquid part of which is carried over in excess by the thread, as shown by the arrow f. A scraping hatchel 26 acting as a wiper is arranged to remove excess liquid from the thread and return it to the tank 24 from which it came. The liquid which flows down over the first ridge 14 without being picked up by the thread F continues to flow downwards in the bottom of the channel until it reaches the second ridge 14 where part of it impregnates the thread and the other part is carried over in excess, the function of removing the excess from 4 5 the thread being performed by the first ridge 14 in a similar manner to that of the scraping hatchel 26. This is repeated for the further ridges 14 which thus act as scrapers for the liquid fed by the lower ridges to the thread and ascending with said thread from the lower ridges and as liquid feeders for the lengths of thread extending immediately in-contact with them. That is, there is a true and proper continuous replacement of exhausted liquid by new active liquid on the thread and therefore the liquid is fully utilized. The final excess of liquid flowing along the plate is collected by a drip vessel 28 which directs it into the lower collecting and recovery channels 29. i

The spacing of the threads away from the bottoms of the channels 13 eliminates excessive friction which would lead to intolerable permanent stretching of the thread.

After leaving the scraping hatchel on comb 26, each thread passes completely round both rollers 9 and 11 and time is thus allowed for a condition of equilibrium inthe concentration of liquid to be reached in the interior of the thread by osmotic diffusion before the thread passes into the next channel 13. A number of different treatments may be applied to the thread by supplying different treatment fluids to the different channels 13 along which the thread passes in successive phases of its movement.

In general, the processes which make up the treatment of the thread in the channels 13 consists of a washing with water to eliminate acidity, desulphurizing to eliminate sulphur and sulphides, bleaching, washing to eliminate the bleaching agents, dyeing, soaping and sizing when required. Additional treatments may be provided for if required, an appropriate number of channels 13 being provided.

From its last convolution round the rollers 9 and 11, the thread F is delivered to a collecting device such as the centrifugal spinning box 30 shown in Figure 5 or to bobbins. The cakes or spools thus obtained are dried in suitable channel dryers.

According to a subsidiary feature of the present invention, an electric motor having an internal stator and an external rotor is .used for driving the centrifugal spinning box. A motor having a rotor which revolves round the stator thus replaces the normal electric motor designed for high speeds of the order of 12,000 revs./minutes, the rotor 34 being shaped as a pulley so as to control the counter-pulley 35 of the centrifuge basket shaft. In this way, by making use of an electric motor designed to give the usual number of revolutions, and thus of relatively simple construction and satisfactory functioning, the centrifuge basket is made to operate at the required speed. In Figure 5, 31 indicates a threadguide for distributing the thread to the spinning box 30 and 32 indicates the control means of the shaft 33 and of other collecting and centrifuging devices.

The apparatus described may be modified in many ways. For example, some or all of the channels 13 in the washing plate 12 may have only one ridge 14 and the plate may be heated by electric resistors instead of by hot water or by steam. Oscillating thread guides may replace the rotating hatchel 21. Although the system of controlled distribution of the liquids from the tanks by means of the rods 25 is preferred, it may sometimes be advantageous to use other systems. The scraping hatchel or comb 26 may be totally eliminated and its function taken over by an appropriate ridge 14 suitably shaped and distant from the lower ridges 14 of the plate 12. In this way, it might be convenient to incorporate the receptacles 24 in the plate 12 and possibly to equip the latter with suitable internal tubes joining up with those from the receptacles. Although it is preferred to use deflecting devices such as the devices 19, 19', 20 and 20' for initially holding the threads away from the channels 13, the same result could be obtained by supporting the guide ascaaee plate 12 so that it can be moved away from the threads.

While there has been herein described the preferred embodiment of the invention, various modifications and substitutions may be eflected without departing from the inventive concept as properly comes Within the scope oi the appended claims.

I claim:

1. An apparatus for the wet treatment of thread, comprising a pair of spaced-apart rollers positioned above each other and defining a multi-convolution path for said thread having a series of substantially parallel ascending and descending reaches; guide means for the convolutions of said thread, said guide means forming a plurality of sloping, substantially parallel channels positioned to receive respective ones of said ascending reaches, said guide means further comprising a plurality of thread-supporting projections in each channel spaced apart in longitudinal direction thereof, said projections being adapted to keep said thread clear of the channel bottom; and a source of treatment liquor positioned adjacent said guide means and adapted continuously to discharge said liquor at a controlled rate into at least one of said channels, said source including a rod of inverted J-shape having a longer depending leg terminating at an adjacent channel of said guide means and a receptacle for said liquor receiving another, shorter leg of said rod.

2. An apparatus according to claim 1, wherein said source is positioned for delivery of said liquor to the upper end of a channel of said guide means.

3. An apparatus according to claim 1, further comprising wiper means adapted to remove excess liquor from said thread and positioned above said guide means for engagement with a thread portion ascending from a liquor-supplied channel.

4. An apparatus according to claim 3, wherein said wiper means is positioned adjacent said receptacle for returning said excess liquor to the latter.

5. An apparatus according to claim 1, wherein said guide means comprises a hollow board formed with said channels and provided with internal heating means.

References Cited in the file of this patent UNITED STATES PATENTS

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