US2285584A - Twister cap - Google Patents

Description

TwIsTER cAP f- June 9, 1942.

' rotation.

the bobbin is full, the

around the lower end of the cap, being in con- Patented June 9, 1942 Ivern J. Jordan,

mann, Lakewood,

and Alden H.

OFFICE Richard F. Berg- Burkholder,

Cleveland, Ohio, assignors to Industrial Rayon Corporation, Delaware Cleveland, Ohio, a corporationfof Application June 3, 1941, Serial No. 396,420

This invention relates to caps for use in captwisting apparatus of the kind employed in twisting thread or the like.

In the operation of cap-twisting apparatus, the thread or the liketo be twisted is drawn from a suitable source, through a` thread guide dislower edge of thel cap, the outside of the cap in what is known as a Twist is imparted to the thread by thread as it leaves the source.

When the twisting operation is rst begun; i. e.. with the bobbin empty, the thread travels about Y ,the `cap in a path bowed laterally outward from the side of the cap but otherwise extending sub- As the bobbin iills, the threadpath becomes progressively more bowed, particularly in the vitime, the path of the thread between the thread the lower edge of the cap assumes an increasingly pronounced spiral form imposed by relative lateral displacement of the upper and lower portions of the thread path. By the time thread is in eiect wrapped tact with the side of the capforseveral inches above the edge thereof. A

In the meanwhile, the angle between the length of thread passingfrom the edge of themap to the surface of the bobbin and an imaginary tangent to the cap at the point where the thread passes under the edge of the cap gressively smaller. As the angle is decreased, the component of force operating to cause the the thread travels about upper edgev of the cap. At the same becomes pro- 1a claims. (cl. 57-127) thread onto the bobbin mers dimcumyy @mybeside and lower edge of the cap isincre'ased .to a degree as to cause a drag in the thread itself.

y Inasmuch as vconsiderable friction is developed as the thread moves around the cumbersome and 4costly to manufacture. They do, of` course, have the importantadvantage lof being rigid in construction. f v

Heretofore, `most twisting operations have been over.v It is worn away even more quickly when,

cap are of great importance. In apparatus of the kind f disclosed in Patent 2,225,642, as many as 10,000

may be employed simul eously in a single between the thread and the' cap, the partv or v often the case, it is a pigmented thread thatv cap-twisting units V phere.

2 l plant. When it is desired to remove a completely fllled bobbin from one of these units, the opf era'tor grasps the top of the twister cap with one hand, removing it from the spindle assembly by lifting it upward. With the other hand he grasps the top of the filled bobbin, removes it from the spindle assembly, places it in a rack, and replaces it with an empty bobbin. This done, he replacethe twister cap. Since the operator continues to hold the twister cap in the same hand throughout these operations, it is desirable to employ a cap that islight in weight; however, it

is no less important that the: cap berigid.

In order to keep down the weight of the cap, it should obviously be as small as possible. Where, however, the amount of thread being twisted in one length is an important factor, it is necessary to wind a package as large as possible at the highest practicable speed. In such circumstances, a two-fold desideratum is presented; viz., keeping the twister cap as small as possible while winding the largest possible thread package. Y

The necessary combination of rigidity, light weight and satisfactory wearing qualities is to be found in the capof the present invention, which cap is highly resistant to corrosion, strongly con- `structed, yet very light -in weight. The surfaces of the cap in contact with the thread are so constructed as to reduce toa minimum the fricgtional drag upon a the a yarn passingfthereover. fThe cap as a whole, including the parts thereof coming into contact with thread, is of materials which are particularly adapted to use` in captwisting apparatus operated in a humid atmos- Without intending to limit the invention thereto, a particularly satisfactory embodiment of the invention is4 illustrated in the accompanying drawing. Figure 1 is a `sectional elevation of a portion of a cap-twisting apparatus showing the twister cap of the present invention, the bobbin,

Yand the parts 'of `the spindle assembly normally associated therewith. Figure 2 represents a side elevation of the apparatus from line 2-2 of Figure l. Figure 3 is a portion of the sectional elevation of Figure 1-.on a greatly enlarged scale, the portion being from the lower edge of the cap.

'As shown in Figure 1, the apparatus as a whole comprises a stationary spindle shaft I surrounded by a sleeve, 2 capable of reciprocating lengthwise of spindle shaft I, the sleeve being shown in its uppermost position. A collar 3 fixed to sleeve 2 serves to carry rotary whorl and bobbin support 5. Bobbin 6 is mounted on support 5, rotational movement from a belt (not shown) being transmitted thereto by means of Iwhorl 4 and support 5. Thus while spindle shaft I remains stationary,` sleeve 2 can reciprocate vertically and whorl 4, support 5 and bobbin 6 can rotate about sleeve 2 as it reciprocates.

Cap 1` is mounted in the usual way on the upper end of spindle shaft I in such manner that the movable parts ofthe spindle assembly can reciprocate and rotate within the cap.

The cap itselfk includes a boss 8 to which is attached a dome 9, such dome serving to support skirt I0. ,Ring II is attached to the lower lend of skirt I0 to guide the thread A in the manner hereinafter explained as it is being wound in package form on bobbin 6. Boss 8 has formed therein a ltapered bore I6 which seats cap 1 upon tapered surface I1 of spindle shaft I tohold the cap in place, the weight of the cap being sufcientto hold it on the` spindle dome 9. Shoulder 2I on dome 9 and shoulder 22 on skirt Ill also assist in holding the, partsof the cap in assembled relation, particularly if a cementitious material is employed to bind the parts together. Such ya construction makes it possible to assemble and disassemble the cap with ease and rapidity.

4Skirt III is of laminated construction, being made of a synthetic plastic such as Bakelite whichl is reinforced with sheets of flber,'cloth,

paper or other suitable material. One laminated plastic of this type is sold under the trade-name Micarta. Such materials not only are resistant to corrosive fumes but take on a high polish which is maintained during and in some cases even improved with use. Since, according to the present invention, no thread comes into contact with boss 9 or dome 9, both of the latterl may be painted with lacquer or otherwise coated to prevent corrosion.

Ring II is fitted on the end of skirt I0, shoule der 29 on skirt III serving to locate ring II on said skirt; preferably, ring II is cemented to the ,skirt I0.

`inasmuch as the greatest wear takes place where the thread passes around the edge of ring II, such ring is preferably made of a'high grade stainless steel such as the hardened nickel-free chrome alloy steel known in the trade and under SAE specifications as stainless steel alloy 420 or Carpenter 2 vstainless steel. This alloy,

`whichis of the same quality as high grade cutlery steel, is not only capable of being hardened but of taking on a high polish. An analysis of this alloy shows that it contains about .30% carbon and about 13.00% chromium. In lieu thereof, various other alloys which are equally or more resistant to abrasion may be employed.

As appears from Figure 3, ring I I is beveled to provide a definite relationship between outer surface 24 and inner surface 25, arc 25 serving to join the two surfaces. Preferably inner surface 25 is at an angle of approximately 30 to outer surface 2B. Arc 2B is tangent to both outer surface 24 and inner surface 25. The radius'of arc 26 should be less than .01 inch whenthe twister cap on which it is mounted is approximately ten Y inches long and five inches in diameter and the collecting bobbin on which the thread is being wound is approximately 2% inches in diameter. This radius serves adequately for thread having a denier as low as or lower than one hundred.

The radius of the arc joining the beveled inner surface 25 of ring II with thev outer surface 2l thereof is determinative of the path of the thread in the balloon, this following from the fact that, by decreasing the tension in the thread, the reduced radius allows the thread to be bowed farther outward from the cap.

If, because of rapid wear, the radius changes within a relatively short time, the critical character of such radius becomes even more critical. With a hardened steel alloy of high quality, it is possible to machine the rings down to a tolerstainless steel variety may be ever features oi' Lto which they are subjected.

3 what is calmed is:

d l. A twister cap comprising ametal dome; a

when thread of o denier, 4o filaments, 1s

being twisted, the preferred radius of the arc 26 is approximately .005 inch, plus or minus .002 inch. The diameter of the empty bobbin should in such case be approximately 2% inches. Under these conditions, the balloon will completely miss the upper portion of twister cap l from the very start of the winding operation, being far enough from the upper edge of the cap to be free from contact therewith even in the twisting of thread of low denier. This is due to the relatively low tension in the thread between the edge of the ring and the surface of the collecting bobbin, as well as between the lower edge oi' the cap and the thread guide above the cap.

At the same time, the tension in the thread between the lower edge of the cap and the periphery of the bobbin is substantially reduced.

The apparatus of the invention is particularly suitable for use in high speed winding operations. For instance, when the thread to be twisted passes from the source at a linear speed of approximately 76 meters per minute, the bobbin upon which the thread is collected is rotatedat an angular velocity of approximately 8,000 revolutions per minute. This impartsa twist of approximately two and one-half turns per inch to the thread. Operations at such high speed necessitate apparatus which is durable and yet efiicient in operation: these requirements the apparatus of the present invention amply satises.

The twister cap illustrated in the drawing represents the preferred embodiment of the invention as it is employed in the twisting of pigmented thread at comparatively high speeds. However, modications as to construction and use of materials may be made without departing from the spirit of the invention. Skirts made according to the invention may be constructed of plastic material which has sumcient strength in and of itself without laminae incorporated therein; also, the ring may be made of other types of wear-resistant material than that described herein. For instance, if the apparatus is not operated in an atmosphere of a wear-resistant metal not necessarily of the employed. It is intended that the patent shall cover, by suitable expression in the'appended claims, whatinvention.

high humidity, etc..

patentable novelty reside in the on-metallic skirt attached to said dome; and. attached to the lower end of said skirt, a beveled ring of wear-resistant material, the inner and outer surfaces of said ring being joined by an arc tangent to both of said surfaces.

2. A twister cap comprising a metal dome, said domeincluding a mounting boss; a substantially4 cylindrical non-metallic skirt attached to said dome; one or mcreannular ridges adjacent the lower edge of said dome; one or more annular grooves adjacent the upper edge of said skirt. said grooves cooperatingwith said ridges to hold said dome and said skirt in assembled relation; and a wear-resistant ring mounted at the lower edge of said skirt.

3. A twister cap comprising a. metal dome; a non-metallic skirt attached to said dome; and a hardened metal ring mounted at the lower edge of said skirt.

4. A twister cap comprising a metal dome; a substantially cylindrical molded plastic skirt; and, mounted at the lower end of said skirt, a hardened metal ring. A

5. A twister caplof the character described in claim 4 wherein the skirt is made of plastic material having a non-metallic reinforcing material incorporated therein.

6. A twister cap of the character described in claim 4 wherein the ring is made of a hardened steel alloy. A l

7. A ring for twister caps comprising a bevv eledl annular ring, the inner and outer surfaces of said ring being joined by an arc having a radius not greater than .01 inc 8. A ring of the character described in claim 7 which ring is made of a stainless steel alloy..` a

9. A ring of the character described in claim 'I in which the inner and outer surfaces thereof are inclined to each other at an angle of approximately 30.

l0. A ring of the character described in claim 7 in which vthe arc is tangent to at least one of said surfaces.

il. A ring of the character described in claim 7 in which the radius of the arc is from .003 to .Lai/EBN J. JORDAN.

1:1 F. BERGMANN. 1 H. BURKHOLDER.

hardened, nickel-free.

Images