US2618021A

US2618021A - Apparatus for the continuous treatment of filamentary material

Info

Publication number: US2618021A
Application number: US86072A
Authority: US
Inventors: Lipscomb Robert
Original assignee: Imperial Chemical Industries Ltd
Current assignee: Imperial Chemical Industries Ltd
Priority date: 1948-04-19
Filing date: 1949-04-07
Publication date: 1952-11-18
Anticipated expiration: 1969-11-18
Also published as: GB649997A

Description

Nov. 18,1952 R. LIPSCOMB APPARATUS FOR THE CONTINUOUS TREATMENT OF FILAMENTARY MATERIAL Filed April 7, 1949 Inventor ROBERT LIPSCOMB Attorneys v Patented Nov. 18, 1952 APPARATUS FOR THE CONTINUOUS TREAT- MENT OF FILAMENTARY MATERIAL Robert Iaipscomb, Welwyn, England, assignor to Imperial Chemical Industries Limited, a corporation of Great Britain Application April 7, 1949, Serial No. 86,072 r In Great Britain April 19, 1948 p 14 Claims. (01. 190.46l

This invention relates to an improved process for subjecting continuous lengths of filamentary material to .a number of after-spinning treatments in one continuous'operation.

In the production of artificial filaments for use for such purposes as synthetic bristles or fishing lines,nit is necessary after the actual spinning operation to subject the filaments to various after spinning treatments. ,In the production of nylon filament, for example, the following steps are required. The filament after drawing undergoes a conditioning treatment in boiling wateror steam, drying and finally guillotining into short lengths. [At the present time this is commonly done by a number of separate steps. For example the nylon filament from the spinneret passes through a quenching bath and is then wound onto a bobbin. From this bobbin it is unwound and subjected to drawing. After drawing the filament is wound onto a beam on which it is subjected to a conditioning treatment. Finally the filaments are cut at one end of the beam and after removal from the beam the hank is dried and then the curled j ends are removed by a guillotine leaving a bundle of lengths of filaments, each about four feet long. It will be appreciated that the operation of all the above steps involves considerable manual labour and take 'a long time;

An object of the present invention is the provision .of a process wherein a continuous filamentary material may be subjected to a number of different treatments in one continuous operation.- A further object isthe provision of such a process which involves a minimum amount of manual labour. A still further object is the provision of one continuous process in which all the steps in the after-spinning treatment of continuous artificial filaments may be carried out.

According to the present inventionthes'e objects are accomplished by a process wherein a continuous artificial filament is laced in a zig-zag path between two lines of pegs, spaced apart and side by side, projecting from an endless conveyor which carries the pegs and the filament through various treating zones to a receiver- In the treatment of an artificial filament it is preferable to lace the filament around the pegs as it comes from the spinning orifice. This enables the spinning and treating of artificial filaments to take place in one continuous process.

In many cases the lines of pegs will be substantially parallel but this is by no means essential. Indeed, in a preferredmodification, particularly suited for the after-spinning treatment of nylon filament, the lines of pegs travel parallel for a l 2 I portionof their'journey, then diverge so that filaments laced around the pegs are drawn. They may also gradually diverge to draw the filament gradually, or converge to allow the filament to relax. I

In the following example, which illustrates but does not limit the scope of our invention, a nylon filament is treated on a preferred type of apparatus. The apparatus, which is shown in the attached drawings, takes the place of the drawing machine, beam winder, conditioning tank, guillotine and drying oven commonly used in the manufacture of nylon filament for use'in the production of artificial bristles. Figure 1 is a diagrammatic plan view of the apparatus, not to scale, Figure 2 is a vertical section through the line zv :r in Figure 1.

Example The conveyor'in this process consists of two heavy conveyor chains I, of 5 inch pitch driven

round sprockets

2 and 2A, mounted in pairs on vertical shafts 3, as shown in Figure 2, so as to rotate in a horizontal plane.

The upper surfaces of the two chains rotate in the same horizontal plane and the chains follow a path such that over a portion of their length they travel parallel and 2 feet apart then diverge to a distance of 8 feet apart and finally continue parallel and 8 feet apartfor a further portion of their length before passing round sprockets and returning to their starting point. On the upper surfaceof the chains, short steel pegsl, each two inches high, project upwards from the plates of the chain links. These pegs resemble bollards in shape being waisted in the middle to diameter and being larger in diameter above and below this waist.

Nylon filament 5, from the quenching bath, below the spinneret, passes through'the guide of a traverse feeder mechanism (not shown) to the pegs on the chain conveyor mechanism. The continuous filament is fastened round one peg and the pegs during this drawing operation and providing non-uniform filaments, two rubber wheels 6, mounted on the same shaft as the sprockets 2A, press the filament into contact with the pegs over the portion of the chain length where drawing commences as shown in Figure 2.

When drawing is completed the drawn filament is carried by the chains through a conditioning chamber 8 into which steam is passed and then into a second chamber 9, where a current of hot air dries the filament. At the end of this machine the filament leaves the drier and is conveyed to the receiver where the stretched span of the filament meets rotating knives 1, rotating in parallel planes at right angles to the filament, which cut the filament into short lengths. To prevent the filament slipping after cutting, the filament is again held against the pegs by means or rubber wheels 6 above the sprockets 2A and on the same shafts which press the filament on the pegs during the cutting operation. The cut lengths of straight filament fall into a tray and can be bundled without difficulty. The length of the cut pieces may be varied by variation of the position of the knives and additional knives may be mounted between the two shown if desired.

While in the foregoing description particular reference has been made to nylon it will be appreciated that the apparatus may be applied to all artificial filament forming material.

The type of treating zone used will obviously depend upon the filament being treated. The apparatus used for the construction of the zones, i. e. liquid bath or gas or vapour tunnels is that commonly used in the art.

While in the apparatus described the material comes direct from the spinneret to the conveyor this is not essential. The filamentary material may be reeled and then fed to the conveyor if desired.

The peg dimensions and constituent material will depend upon the filamentary material being treated and so too will-the material and construction of the conveyor. Pegs should be constructed of hard wearing material otherwisefrequent replacements will be required. For the treatment of filaments when no drawing operation is required broad conveyor bands carrying both lines of pegs may be used. If however a drawing operation is required or if the filament is subjected to a treatment which results in shrinkage, heavy conveyor chains mounted on sprockets are preferred as the forces used in the drawing operation and exerted during shrinkage, may be very great.

The shape of the peg is only limited by the fact that the filament must be laced from one line to the other. The waisted bollard shaped p'eg is preferred as it permits easy lacing and also prevents the filament slipping from the peg. The chains may follow any desired path and need not carry the filament in a horizontal plane.

The path may be accurately and firmly prescribed by means of sprockets and guides.

During the cutting or drawing operation utilising the apparatus described hereinbefore, rubber wheels are used to prevent the filament slipping over the peg surface. It will be appreciated that the wheels need not be made wholly of rubber or like resilient material but may have a metal centrepart with a resilient tyre.

Although only two cutting wheels are shown in the example any number may be used, depending upon the length of filament required.

Tapered filaments, which are used in the production of artificial bristles, may be treated using the apparatus of this invention. In treating tapered filaments the position of the filaments on the pegs is controlled so that the portion passing round a peg of the machine is always in the same part of the taper, e. g. midway along the thick portion of the filament (the width between the lines of pegs being made a multiple of the taper pitch) to ensure that the rotating knives are located so that they always out the strands at the same part of the taper, e. g. midway along the thick or thin portion and so that the cut pieces are all in phase with each other.

The process is particularly suited for treating artificial filaments of nylon or of one of the highly polymerised polymethylene terephthalates described and claimed in British specifications Numbers 578,079 and 590,451.

Utilising the process of this invention reduces the cost of the after-spinning treatment of artificial filamentary material considerably, the manual operationsbeing reduced to a' minimum. Furthermore the final product is homogeneous and is collected in a form very suitable for packaging with the minimum amount of waste.

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed I declare that what I claim is:

l. A process for the production of short lengths from artificial filamentary material of continuous character and capable of being cold drawn which comprises lacing a continuous filament in a substantially zig-zag path between two series of points the locus of which constitutes two lines lying in a plane, drawing the laced filament by causing said points to diverge at a position beyond the position of said lacing of the filament between said points then passing the drawn filament through treating zones to a position where the treated filament, while being held between said diverged points is cut in at least two places along the length of the filament portions held between said diverged points, the maximum length of filament cut being determined by the distance apart of said series of points.

2, A process according to claim 1 wherein the lines of points are parallel during at least part of the process.

3. A process according to claim 1 wherein the filament comes to the conveyor direct from the spinneret.

4. A process according to claim 1 wherein the filament is an artificial tapered filament and the distance between the lines of points is such that the portion of the filament in contact with the points is always the same part of the taper.

5. A process according to claim 1 wherein the filament is of nylon.

6. A process according to claim l'wherein the filament is composed of highly polymerised polymethylene terephthalate.

7. Apparatus for the continuous production of short lengths of cold drawn artificial filamentary material from a contniuous' lengthof undrawn material laced in zig-zag fashion between two lines of pegs in the same plane, which comprises a pair of endless conveyors which are spaced apart and sideby side, and which carry said two lines of pegs, means for causing said endless conveyors to diverge so that the distance between the lines of pegs increases to draw said filament, treating chambers through which the drawn filament is carried by said endless conveyors ta g I smash point where at least two cutting wheels, rotating in planes substantially at right angles to the filament, cut the filament into'short lengths, and a container to collect the cut lengths.

8. Apparatus according to claim 7 wherein the pegs are waisted to prevent the filament slippi s o 9. Apparatus according .to claim 7 wherein the lines 01' pegs are parallel during at least part of the time when they are conveying the filament.

10. Apparatus according to claim 7 wherein wheels having a perimeter of rubber or like re silient material press the filament against the pe s.

11. Apparatus according to claim 7 wherein the conveyor consists of two endless chains rotating in a plane, around sprockets with the pegs projecting in the same direction from plates of the links of eachchain. the chains being caused to diverge by the suitable positioning of the sprockets. v

12. Apparatus according to claim 7 wherein one 0! the treating chambers is a steam chamber. 13. Apparatus according to claim 7' wherein one of the treating chambers is a hot air oven. 14. Apparatus according to claim 7 wherein the cut lengths fall onto a moving band.

ROBERT LIPSCQMB.

REFERENCES CITED The following references are of record in the file of this patent: