US1337258A - Device for forming filaments - Google Patents

Description

0. OHLSON.

DEVICE FOR FORMING FILAMENTSf APPLICATION FILED MAY19. 1919,

1 33732 Patented Apr. 20, 1920.

OLOF OHLSON, OF WEST NEWTON, MASSACHUSETTS.

DEVICE FOR FORMING FILAMENTS.

Specification of Letters Patent.

Patented Apr. 2%, 1920.

Application filed May 19, 1919. Serial No. 298,315.

To all whom it may concern:

Be it known that I, OLOF OHLsoN, a citizen of the United States, and resident of West Newton, in the countyof Middlesex and State of Massachusetts, have invented an Improvement in Devices for Forming Filaments, of whichthe following description, in Connection with the'accompanying drawings,- is a specification, like reference characters on the drawingsrepresenting like parts.

This invention relates to a device for forming filaments for the production of thread or yarn made from cellulose compounds or similar material.

In the manufacture of such threads or yarns, the cellulose compound is in liquid form, in solution, and the liquid is forced through a number of minute orifices into a coagulating bath which causes the material to solidify as its issues in the form of a jet from each orifice and thus produces a filament, which is associated with a number of similar filaments which are slightly twistedtogether and upon emergence from the coagulating bath constitute a strand of the yarn which may subsequently be utilized in the manufacture of thread or fabric.

The device which is used in this process and which contains a number of orifices corresponding to the number of filaments that are to be associated to form a single strand of the yarn or thread is commonly called a spinneret, and the present invention consists in a novel construction of the spinneret.

The production of a satisfactory spinneret is attended with considerable difiiculty as it must be strong enough to withstand considerable pressure, and the orifices by which the filaments are formed are extremely minute, but for a satisfactory product require to be of equal size in the same spinneret, and heretofore the spinnerets have commonly been made of glass and are thus fragile and liable to breakage.

In accordance with the present invention the main body of the spinneret is of metal, being in the form of a cup, the walls of which are thick enough to withstand the pressure to which the spinneret is subjected in the operation of forcing the solution through the same.

It has been found impracticable to form the minute orifices in the metal body of the spinneret by drilling or punching, but I have discovered that suitable orifices can be formed in small relatively thin plates or disks by punching, orwith some materials by drilling, and in accordance with the present invention the main bod of the spinneret is provided with a nuin er of relatively large perforations or holes corresponding in number to the number of filaments desired, and in each of said perforations is secured a relatively thin disk having the minute perforation which constitutes the jet orifice by which the filament is made.

Figure l is a side elevation of a spinneret embodying this invention;

Fig. 2, an end elevation thereof, and

Fig. 3, a sectional detail on line X Fig. 2 on a greatly enlarged scale to show the construction at one of the orifices.

The main body 2 of the spinneret may be of usual form and is composed of metal which may be drawn to the proper shape, which is that of a cup provided with a flange 3 around its open end, and having its closed end or bottom 4 (see Fig. 2) provided with the desired number of orifices to corresppnd to the numberof filaments to enter into a single strand of the yarn which is the product of the apparatus to which the spinneret pertains.

In the example illustrated, there are 16 such orifices and they are extremely minute, being scarcely visible to the naked eye in the actual structure.

The wall or body of the spinneret 2 has to be of considerable thickness in order to withstand the pressure under which the liquid is forced through the orifices and it has been found impracticable to provide suitable orifices by perforations formed directly in the wall of the spinneret when made of metal, and in accordance with the present invention the bottom portion 4 of the spinneret in which the orifices are to be contained is provided with relatively large perforations or openings 5, shown in Fig. 3 as counterbored to form a shoulder 6 between the inner and outer surfaces of the end wall of the spinneret.

In each of the openings 5 there is secured an orifice plate 7 which'as shown in Fig. 3 is pressed tightly into the counter bore and against the shoulder 6.

The orifice plate '2 is relatively thin as compared with the wall of the spinneret in which it is secured and it is preferably recessed as shown at 8 on one side to reduce the thickness at the middle, where it is provided with a minute perforation 9 that constitutes the orifice through which the solution is forced to form the filament.

It is to be understood that as shown in Fig. 3, the dimensions are greatly exaggerated as the passage or orifice 9 is too small to be capable of correct representation of its actual size by drawing.

The orifice plates themselves are so small that although the fluid pressure is large, the area of the orifice plate exposed to pressure is so small that the total pressure upon it is only very slight and is insufficient to distort or dislodge the orifice plate. lVith a pressure of two hundred pounds to the inch, the pressure on each orifice plate is less than a pound.

It is an advantage that the part in which the orifice is formed is very thin, as it makes the length of the bore quite short as compared with the usual construction, and the orifice is less likely to become clogged in use and is more readily cleared or freed if it should at any time become clogged.

The orifice plates being of uniform construction are capable of being manufactured economically and with the required degree of accuracy and uniformity and it is possible in some cases to replace one or more orifice plates in a spinneret if it becomes permanently clogged or damaged in any way without requiring a complete new spinneret as is the case when the orifices are formed in the body of the spinneret itself, with which construction a single defective orifice necessitates the discarding of the en tire spinneret, if a satisfactory product-is to be obtained.

What I claim is:

1. A spinneret or device for forming filaments from a liquid solution composed of a cup like metallic body having a plurality of relatively large passages through the bottom wall ofthe cup combined with relatively thin orifice plates secured in said passages each provided with a minute perforation or orifice, substantially as described.

2. A spinneret or device for forming filaments from a liquid solution composed of a cup like metallic body having a plurality of relatively large passages through the bottom wall of the cup combined with relatively thin orifice plates secured in said passages each being of reduced thickness at its middle part and provided with a minute perforation through said reduced portion.

3. In a spinneret or device for forming filaments from liquid solution, a cup like metallic body portion having a plurality of relatively large passages through the bottom wall of the cup, each counterbored to provide a shoulder between the inner and outer surfaces of said bottom wall, combined with relatively thin orifice plates contained in said passages and seated against said shoulders, each orifice plate being provided with a minute perforation, substan tially as and for the purpose described.

In testimony whereof, I have signed my name to this specification.

OLOF oHLsoN.

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