US2737688A

US2737688A - Tow opening device

Info

Publication number: US2737688A
Application number: US356983A
Authority: US
Inventors: Wallace T Jackson
Original assignee: Eastman Kodak Co
Current assignee: Eastman Kodak Co
Priority date: 1953-05-25
Filing date: 1953-05-25
Publication date: 1956-03-13
Anticipated expiration: 1973-03-13

Description

March 13, 1956 w. T. JACKSON 2,737,688

TOW OPENING DEVICE Filed May 25, 1953 Wallace ZJackson INVENTOR.

United States Patent .Ofiice TOW OPENING DEVICE Wallace T. Jackson, Kingsport, Tenn., assignor to East man Kodak Company, Rochester, N. Y., a corporation of New Jersey Application May 25, 1953, Serial No. 356,983 3 Claims. (Cl. 19-66) The present invention relates to an apparatus for processing of textile filaments, and more particularly to the removal of shiners or married fibers in the tow. The term tow is used to designate a strand of yarn composed of a large number of continuous filaments. A single tow usually consists of from 500 to 5,000,000 single filaments which range in size from a fraction of a denier to 30 deniers per filament. The word shiners or married fibers are used, in the present instance, to'describe the condition where two or more filaments are stuck together and do not easily separate in textile processing. When tow is converted to various fiber lengths, if the shiners are not removed a staple of poor openness results, the disadvantages of which will be readily apparent to those in the art.

The idea of improving the openness of textile staple is not new. This has usually been accomplished in picking and carding machines; and, in some instances, in pin drafters. These machines primarily serve other purposes and consequently result in adding to costs and lower efiiciencies. When shiners and married fibers are removed from the staple previous to conventional textile processing machinery, the efiiciency of these machines has been increased considerably.

The present invention has as its principal object the provision of a new and simplified device for opening a tow.

Still another object of the invention is to improve the openness of synthetic filament textile yarn by removal of shiners and married fibers while the yarn is in tow form.

And yet another object of the invention is the provision of a tow opening device in which mechanically moving parts are absent.

Yet another object of the invention is the provision of a tow opening device which is simple in structure, relatively inexpensive to manufacture, comprises few parts of rugged construction, easy to operate and highly effective in use.

To these and other ends the invention resides in cer' tain improvements and combinations of parts, all as will be hereinafter more fully described, the novel features being pointed out in the claims at the end of the specification.

In the drawings:

Fig. 1 is a perspective view of a tow opening device constructed in accordance with the present invention.

Fig. 2 is a longitudinal sectional view through the tow opening device of the present invention and taken substantially on line 2-2 of Fig. 1, and showing the relation of the parts; and

Fig. 3 is a transverse sectional view taken through the tow opening device and taken substantially on line 3-3 of Fig. 1.

Similar reference numerals throughout the various views indicate the same parts.

In the tow opening device of the present invention, the tow 10, usually pretreated for correct amount of lubri- 2,737,688 Patented Mar. 13, 1956 cant and crimp, is drawn over a curved guide 11 and then into a thin rectangular slot 12 formed in a separating or opening device, generally indicated by the numeral 13. The latter is in the form of a hollow boxlike member formed with a top 14, a bottom 15, opposite end walls 16, a back 17 and a front 18. The slot 12 is formed by means of a pair of spaced

parallel wall members

19 and 20 which are positioned between and parallel to the top 14 and bottom 15, as shown in Figs. 2 and 3. The front wall 18 and back wall 17 are provided with

apertures

21 and 22 respectively, which are equal in size to and in alignment with the slot 12, as best shown in Fig. 3. The space 23 between wall member 19 and top 14 and the space 24 between wall member 20 and bottom 15 provides plenum chambers which are connected by means of

pipes

25 and 26, respectively, to a suitable source, not shown, of gas under pressure, such as an air compresser. A suitable take-up mechanism, not shown, such as ball warp or feed rolls of a staple machine controls the rate of speed that the tow 10 is drawn through the device 13 and slot 12 thereof. In order to open the tow 10 to separate the filaments thereof, the tow, while passing through slot 12,

is subjected to a fluid pressure, such as compressed air or other suitable gas.

To secure this result, each

wall member

19 and 20 is provided with a plurality of rectangular orifices 27 of the shape best shown in Fig. 3, and which extend the full width of the

members

19 and 20, as best shown in Fig. 2. The edges or side walls 28 of each orifice 27 are tapered towards the slot 12, as shown in Fig. 3, to form jets which serve to direct the streams of air or other suitable gas under pressure against the moving tow 10 in slot 12 and in a direction perpendicular to the direction of movement of tow 10 in slot 12, as is deemed apparent from an inspection of Fig. 3. While expansion of the air in slot 12, or upon issuing from slot 12 is inevitable, it is believed that it is the velocity of the air or gas streams impinging on the two 10 in slot 12 which brings about the separation of the filaments. After the air streams issuing from the orifices 27 impinge perpendicularly on the tow 10 in slot 12, the air then diverges in all directions in the plane in which the tow is moving. Approximately half the air exits or escapes from between

members

19 and 20 and through slot 22 in the back wall 17 and countercurrent to the direction of movement of the tow 10 through the slot 12. The end walls 16 close the ends of the slot 12, and prevent the escape of air from the slot at these points, as is deemed apparent.

Referring to Fig. 3, it is seen that the orifices 27 in the

members

19 and 20 are staggered or olfset in the direction of the tow movement so that each

wall

19 or 20 affords. a backing member or support for the tow opposite the orifice in the opposite wall member. Furthermore, this backing member for the tow is substantially at right angles to the air streams issuing from the orifices 27. Thus, the tow is supported opposite each orifice 27 so that the high velocity jets impinge on the tow in slot 12 and serve to shatter the multiplicity of filament bundles.

It has been found that this shattering effect is reduced when the width of slot 12 is increased beyond a nominal setting of A". Test trials have shown that the effectiveness is reduced appreciably with a slot width of It has been further determined that the effectiveness of the device is reduced when the slot 12 is reduced to Ms". It has also been determined that the rectangular orifices 27 are most effective with an opening of 0.008" when processing 80,000 denier (5 denier per filament) tow. When processing 5,000,000 denier tow an orifice setting of 0.020" is optimum. The optimum air pressure supplied to the device through

pipes

25 and 26 is '30 p. s. i. g. when processing 80,000 denier tow, and for 5,000,000

denier tow the optimum pressure is 60 p. s. i. g. While rectangular orifices 27 are shown and preferred, it has been found that a multiplicity of 0.010" diameter orifices are equally effective. Repeated tests have shown that the length of the rectangular orifices 27 is influenced only by the total denier. For 80,000 denier tow the length of the orifices preferably is 6", while for 5,000,000 denier a length of 25" is desirable.

As a specific example of the device of the present invention, the uncompressed cross'scctional area of the compact bundle of filament tow 10 might be, for example, 0.06 square inch. In such case, the length of the slot 12 might be 6", and the height or width y given an area of 1.125 square inches. The five air orifices 27 might be .008 with a combined area of 0.24 square inch (.008 x 5 x 6"). As mentioned above, the optimum air pressure is 30 p. s. i. g. when processing 80,000 denier tow. However, with the device of the present invention a pressure substantially below 20 p. s. i g. may be used. For example, a pressure of 5 p. s. i. g. is sufficient for a tow of 100,000 denier moving at 45 yards per minute. Larger tow and higher speeds require higher pressures, but primarily for the purpose of converting static pressure to velocity pressure. it is believed that the pressure in slot 12 is only slightly above atmosphere.

It is well known that when a tow or staple is processed to increase the openness on conventional textile machines, exceedingly great care must be taken to prevent the formation of neps which are imperfections in textile fibers, such as tangled or knotted filaments. With the device of the present invention, no mechanical fingers, pin, impact boxes, etc, are present. The air jets do not afford any opportunity for the tow to become tangled, and the close restriction of slot 12 prevents loops from being formed. The absence of mechanically moving parts is deemed of considerable advantage.

The present invention thus provides a tow opening device which eliminates the need of mechanically moving parts, and which is simple in structure, inexpensive to manufacture, rugged, easy to operate and highly effective in use.

While one embodiment of the invention has been described, it is to be understood that the inventive idea may be carried out in a number of ways. This application is, therefore, not to be limited to the precise details disclosed, but is intended to cover all variations and modifications therefor falling within the scope of the appended claims.

What I claim and desire to secure by Letters Patent of the United States is:

l. A tow opening device comprising, in combination, a hollow boxlike member, a pair of spaced parallel walls positioned in said member to form a narrow slot through which said tow is moved, said boxlike member comprising a plenum chamber positioned on at least one side of said slot, the wall adjacent said chamber having a narrow orifice which extends substantially the full width of said member for connecting said chamber in fluid communication with said slot, and said orifice having side walls converging toward said slot for directing air from said chamber and into said slot to impinge said tow in said slot in a direction perpendicularly to the direction of movement of the tow through said slot, and means for conducting air under pressure into said chamber.

2. A tow opening device comprising, in combination, a hollow boxlike member having a top, a bottom, opposite parallel end walls, a back and a front, a pair of spaced parallel Walls positioned between said top and bottom and extending between said end walls and between said front and back to provide a thin slot which extends the full length and width of the interior of said member and through which said tow is moved, said end walls closing the opposite side edges of said slot, said back having formed therein a tow entrance aperture in registry with said slot, said front having formed therein a tow exit aperture in registry with said slot, said apertures extending between said end walls so as to have a width equal to that of said slot, said boxlike member comprising fluid plenum chambers positioned between said spaced parallel walls and said top and bottom respectively, said spaced parallel walls having formed therein fluid openings having a width equal to that of said slot to supply fluid pressure to the tow in said slot to open the tow.

3. A tow opening device comprising, in combination, a hollow boxlike member, a pair of spaced parallel walls positioned in said member to form a narrow slot which extends substantially the full length and width of said member, said boxlike member comprising a plenum chamber positioned on at least one side of said slot, means for supplying a gas under pressure to said chamber, the wall on said one side having formed therein a narrow elongated aperture which extends across said slot for the full width thereof for directing a gas stream from said chamber into said slot to impinge the tow in said slot perpendicularly to the direction of movement of the tow through said slot, the wall on the other side backing said tow opposite the point of impingement of said stream.

References Cited in the file of this patent UNITED STATES PATENTS 1,607,220 Von Ehrenthal et al Nov. 16, 1926 2,244,203 Kern June 3, l94l 2,351,549 Schwartz June l3, 1944 2,657,433 Merriman Nov. 3, 1953

Claims

1. A TOW OPENING DEVICE COMPRISING, IN COMBINATION, A HOLLOW BOXLIKE MEMBER, A PAIR OF SPACED PARALLEL WALLS POSITIONED IN SAID MEMBER TO FORM A NARROW SLOT THROUGH WHICH SAID TOW IS MOVED, SAID BOXLIKE MEMBER COMPRISING A PLENUM CHAMBER POSITIONED ON AT LEAST ONE SIDE OF SAID SLOT, THE WALL ADJACENT SAID CHAMBER HAVING A NARROW ORIFICE WHICH EXTENDS SUBSTANTIALLY THE FULL WIDTH OF SAID MEMBER FOR CONNECTING SAID CHAMBER IN FLUID COMMUNICATION WITH SAID SLOT, AND SAID ORIFICE HAVING SIDE WALLS CONVERGING TOWARD SAID SLOT FOR DIRECTING AIR FROM SAID CHAMBER AND INTO SAID SLOT TO IMPINGE SAID TOW IN SAID SLOT IN A DIRECTION PERPENDICULARLY TO THE DIRECTION OF MOVEMENT OF THE TOW THROUGH SAID SLOT, AND MEANS FOR CONDUCTING AIR UNDER PRESSURE INTO SAID CHAMBER.