US2471057A - Method and apparatus for drafting textile fibers - Google Patents

Description

May 24, 1949. F. B R 2,471,057

METHOD AND APPARATUS FOR DRAFTING TEXTILE FIBERS Filed Dec 18, 1945 E E I. E Elk: 6 2 36 "a 47 I"- INVENTOR WH/TWORTH F 2 BY jfRiY Patented May 24, 1949 METHOD AND APPARATUS FOR DRAFTIN G TEXTILE FIBERS Whitworth F. Bird, Swarthmore,

Pa., assignor to Collins & Aikman Corporation, Philadelphia, Pa., a corporation of Delaware Application December 18, 1945, Serial No. 635,642

41 Claims.

This invention is directed to a novel method of and apparatus for the drafting of textile fibers. It has wide application in drafting processes, which includes the drafting of untwisted as well as twisted stock and textile fiber stock having fiber length variations of severa1 hundred and sometimes over a thousand per cent. This degree of variation in fiber length will be found in the long worsted forming type of wool or mohair stock and blends of this wool or mohair with other fibers such as cotton or synthetic fibers, or in combination with both.

Common current procedures are to blend cotton and wool fibers by selecting short fiber wools which have a fiber length nearly that of cotton or of cutting wool top into lengths so that the cut fibers may be spun with cotton on what is commonly described as the cotton system. This system of drawing is generally characterized by the use of a short ratch for the draft stage, as is well understood throughout the industry.

These procedures are uneconomic in that proper short wool fibers are not readily available and the price of worsted top stock is considerably higher. .In addition, the highly important benefits of the long wool staple, both in processing and in the finished yarn, are obviously lost by the prior cutting step.

The use of extremely long and short wool blended with short fibers such as cotton will not draft evenly on known drafting equipment.

Also, if untwisted sliver of such stock is used, conventional slip rolls and an apron will not control the short fibers properly. They will pull through in bunches and the front slip rol1 will often have a surface speed higher than that of the supporting apron. If the weight of the front roll, i. e., that slip roll nearest the usual nose bar, is increased in an attempt to better control the short fibers, the weight will have to be increased to such an extent that the fibers under the roll will not turn it and the frictionally driven apron will actually stall. The area just behind the nip or contact point of the front rolls is the critical drafting area. In this area the fibers engaged by the front rolls are being rapidly separated from the others.

By the present improvements and according to the illustrated embodiments of the invention, I have overcome these economic and manufacturing difficulties. I have done this by providing pairs of draft rolls, operating at progressively higher speeds to produce a draft stage or drafting area, in combination with an apron located wholly or partially within the draft stage arate from the apron.

and a pin roller with or without collars for controlling the fibers as they approach the front nip of the draft stage. The pin roller may be driven by a leather, rubberized, metal, or other flexible apron, or by means such as gears sep- The manner of driving the pin roller is determined by the stock being processed, and when desired the'pin roller may function as a pressure roller as well as a comb, as will be more fully set forth. When collars are used on the pin. roller, the outer pin surface diameterwill usually be slightly less than or equal to the collar diameter.

Pin rollers or porcupine rolls of relatively large size have been used in the known French system and in some other devices for straightening textile fibers in textile processing. It is be-- lieved that in no case have they been used in the environment, combination, or for the purposes of the present invention.

An object of invention is to provide a nonr-atch forming slip draft fiber control roller cooperating with a supporting apron at a point close to the nip of the front rolls of a draft stage, said roll being driven at a predetermined rate by the apron or separate means other than the stock being drafted.

Another object of the invention is to provide a method of and apparatus for the control of textile fibers by means of a continuous supporting apron co-acting with combining means.

Another object is to provide a method of and means for combing fibers being drafted on a cotton or worsted type drafting unit with a minimum of modification to drafting unit.

Another object is -to provide in combination, a depressed support and depressing pin roll in pressure contact witha support at a point close to the forward nip of a draft stage.

Another object is to provide a pin roller and apron combination in which the pin roll is r0- tated at the same surface speed as the speed of the apron.

Another object is to provide a combing action for textile fibers together with improved feed control in the draft stage.

These and other objects of invention will be manifest from a consideration of the description, claims and drawings in which:

Figure 1 is a diagrammatic side elevational view of draft stage components including an apron driven pin or porcupine roll.

Figure 2 is a diagrammatic side elevational view of draft stage components including a depressed apron and a pin or porcupine roll separately driven at the same rate of speed as the apron.

Figure 3 is a diagrammatic side elevational view of draft stage components including a depressed apron and a pin or porcupine roll having collars for cooperating in frictionally driving the depressed apron.

Figure 4 is a diagrammatic sub-assembly view of a simple gear drive for alternate type porcupine collar rolls, either of which may be associated with four adjacent spindles of the frame illustrated in Figures 2 and 3, together with a cooperating roller for driving the apron as in Figure 3. The pins of the pairs of rollers to the right extend slightly short of the collar diameters. This view further shows sections of the aprons 36 which are in running contact with the control rollers in the manner shown in Figures 2 and 3.

Fig. is similar to Fig. v3 except for the passage of the apron about a single driving spool type roll. Like parts have the same reference numerals in Fig. 3 and Fig. 5 except for the short apron, 36', and spool roll 60, Fig. 5.

Referring to Figure 1 in which pairs of rolls Ill, II and l2, 13, respectively, are the front and back rolls of a draft stage. Rolls 10, ll rotate at several times the speed of back rolls I2 and I3 to reduce or draft the fiber stock. A supporting belt or apron l4 maintained under tension by the weight roll I6 is frictionally driven by driven roll I3 against which the apron I4 is pressed by roll [2. Depending on the length of ratch or distance between the nips of the front and back rollers, a supporting roller or rollers l1 and cooperating slip rollers such as l8 may operate to partially control the stock prior to its reaching the comb. The ratch may be slightly in excess of the length of the longest fibers, as is conventional.

The critical drafting area is close to the nose bar [9 which may be triangular in cross section. At or close behind this point, and in accordance with this invention, a porcupine pin roll is mounted so that the ends of the pins 2| rest on the apron l4, and will be rotated by the apron during the drafting operation. It will be seen that the ends of the pins or needles 2| will completely penetrate the stock, bear on the apron, and be rotated by the apron and not by the stock, as is the roller 18. It will be understood that the use of fiber condensers as at the rear of the feed rolls and between the nose bar and front rolls is contemplated in the several figures and has been omitted to emphasize the present improvements.

I have obtained very satisfactory results with anapron and a porcupine pin roll having a 5% inch pin surface diameter, and alternately staggered rows of pins 29 to the inch mounted in 28 rows on a inch roll. Shorter pins or those round at their points may be used when desired. The use of shorter pins enables penetration of the fiber stock for combing and creates additional control of the fibers by pressure of the pin base roll on the fiber stock. This variation is adaptable to both apron and independently driven pin rolls. The pins are mounted at an angle of about 47 to a tangent at the point of pin entry to its sleeve base. These dimensions are illustrative of successful practice and are not considered critical, nor is the particular shape of the comb teeth.

Figures 2 and 3 show somewhat more complicated modifications in that a pin roll is positive-- 17 driven and the apron is tensioned and depressed a subtsantial extent by contact with the pin roll and other tensioning means. In Figure 2 the front rolls 30, 3t and back drafting rolls 32, 33 form a draft stage forwardly of optional feed rolls 34, 35. Apron 36 is looped about nose bar 31, driven roller 33, support roller or cylinder 38, and roll 39 to which a spring 40 anchored at 4| is attached for strongly tensioning the apron 36. A step shaft 42 having porcupine roll 50 with collars 5| keyed thereto as by sunken screws H is so positioned relative to the apron that the ins 45 and collars5l will depress the apron and give a curved path to the stock just prior to its leaving the nose bar 31; The shaft 42 is horizontally and vertically adjustable to fixed positions relatively to the apron 38 and nose bar 31. Carrier roll 21 and slip roll 28 are similar to rolls l1 and I8, Figure 1.

In Figure 2 the pins 45 and collars 5| are .shown as both being in depressing contact with the apron 36. The pin rolls with or without collars are interchangeable in the illustrated embodiments of Figures 1 and 2. There is some preference for the collar roller as it reduces the number of pins required to be set, provides a gauge for pin setting inspection or measurement as by a rule, and facilitates handling without injury to the pins or operator. They do not interfere with the combing of the fibers because they are positioned laterally of the combing area.

Figure 3 is similar to Figure 2 and like parts are given like reference numerals for the sake of brevity. It differs from Figure 2 in that the support roller or cylinder 38 has been removed and adjustable roller 60 is introduced somewhat forwardly of the mere apron supporting position of cylinder 38. The roller 60 presses on the underside of apron 31 at points so as to form frictional nips with the collars 5| of pin rolls 5!], and thus constitute all or part of the frictional apron driving means. In this modification the pins 45 project outwardly slightly. short of the collar diameter 50 as not to be pressed by the roller 60. The difference in diameter of the pin surface and that of the collars is preferably small so that the great bulk of the fiberswithin the combing area are within the pins and the remainder which are in frictional contact with the apron tend to be drawn into the pins as they move upwardly and around the nose bar 31. This movement of fibers into the pins results from the proper relative positioning of the combing members and nose bar and also because the angular disposition of the pins tends to cause contacting fibers, moving at a relatively high rate as in the critical drafting area, to move upwardly along the pins toward the pin support until such time as they are positively drawn out of the combing area by the front rolls of the device. With this construction a shorter apron which does not loop about roll 33 but moves directly from roll 39 to the roller 60 may sometimes be used if the fiber length or type warrant it. As will be seen in Fig. 4 the adjustment of the slip draft rolls and connected drive may be accomplished in any convenient manner such as pairs of screws BI and G2 in fixed journals such as 63. No claim is made to the well known type of adjustment structure shown in the case.

These constructions definitely control the short fibers and in long fiber drafting prevent pulling through of medium length fibers which extend into the critical drafting area, but which are no longer held by the back rolls of the draft stage.

The above described depressed apron embodiapproximate inch more or less.

ments, Figures 2 and 3 of the present invention, are illustrative of the complete fiber control possible for the fibers of stock types most 'difllcult to draft. In general, when the length or type variations among the fibers are somewhat less than maximum, the extent of apron depression may be smaller. It will be often sufiicient to rely on combing the bulk of the fibers with roll pin diameters shorter than that of the collars and on the frictional drag of the supporting apron for the small percentage not definitely pressed into the comb. The difierence in diameters may This construction used in Figure 2, for example, permits small differences in apron and pin roll speed. Depending on the stock being processed, all three types of pin rolls may be used in Figure 1, the pin roll of Figure 1 may be used in the modification of Figure 2 and the collar pin rolls of Figures 2 and 3 are interchangeable for use in the modifications of Figures 2 and 3. If a collar roller having equal pin and collar diameters is used, I prefer to form the roll 60 as a spool to provide clearance in the portion opposite the pins. The spooled roll is shown in Fig. 5 and designated 60'.

Figure 4 shows gear 46 at the end of pin roll shaft "which is driven by gear 41 on shaft 48 connected to a source of power and driven at a rate so that the speed of the pin roll surface is equal to the speed of the tensioned apron. Gears 49 are a booster gear or end gear assembly positioned along the shaft 42. The necessity and number of such gears are of course dependent on the length, weight, etc., of the shaft 42. This figure illustrates two types of pin rollers which may be used.

Types of machines in which my improvements may be used are cotton or worsted roving frames, final spinning frames, or any device in which the drafting of twisted or untwisted slivers or stock is contemplated.

Very superior results have been obtained with the depressed roller and belt or apron 36 especially on stock which has heretofore been considered very difiicult to draw because of fiber length variation of /2" or less to considerably in excess of 5 inches as normally will result from the blending of cotton and wool which has not been cut from top; Nine inch wool or mohair fibers are not uncommon. A typical cotton fiber diagram will show fibers of to 1% inches more or less, whereas wool stock containing fibers of 8 or more inches similarly contains shorter fibers down to a fraction of an inch.

The present improvements have been described in connection with a single draft stage. Their use in multiple stages in a line of draft stages which includes these improvements in one or more stages is within the scope of the invention, as are structural changes including modifications of the length of the pins of the porcupine, the angle of the pins to their point of support, rounding pin ends as by burnishing, and variations in driving arrangements.

The method and apparatus of the invention herein described and illustrated provide positive control of the fibers in the critical drafting area, Control of all, or essentially all, the fibers in this area is insured by positively confining all or the great bulk of the fibers within the path of the preferably angularly disposed teeth of the comb. The confining means .being' flexible functions similarly to an elastomer and its resilience, together with that of the pins, insures eificient operation without damag to operatingparts.

The flexibility of a continuous band of material such as an apronor endless chain type belt depressed by a toothed roller results in a relatively large combing area and fiber control hitherto unattainable as above set forth. Another advantage is that when a positively driven roller is used it does not stall the apron and may operate as a pressure roller which cannot be rotated by movement of fibers with consequent lack of adequate fiber control.

The drafting of the fibers of twisted stock removes the twist before the nip of the front rolls is reached by the short fibers, and hence these fibers may be controlled and combed as above described.

I have described my invention in connection with preferred embodiments thereof, but donot wish to be limited thereto, but rather by the scope of the dependent claims.

I claim:

1. In a drafting device for textile fibers, a pair of front drawing off members, stock feeding means including an endless looped apron having a stock supporting portion, supporting means for the apron including a nose bar close behind the front drawing oif members, an apron tensioning roll yieldingly positioned within the apron loop, a pair of rolls forming a driving nip for the apron, a slip draft roll positioned forwardly of the said apron driving nip and above the apron to provide a restricted fiber passageway, means -for positively driving the slip roll, said slip roll having firm end portions which may press on the tensioned apron and aid in driving it, and a central fiber control portion, said central fiber control portion forming a pressure slip draft passage with the apron for textile fibers being processed, said central fiber control portion being the only fiber control portion of the slip draft roll and being more readily deformable than the firm end portions which aid in driving the apron.

2. In a drafting device for textile fibers a pair of front drawing off members forming a nip, stock feeding means including an endless looped apron,

' supporting means for the apron including a nose bar close behind the front drawing off members, an apron tensioning device for yieldingly tensioning the apron, a pair of rolls forming a driving nip for the apron, a slip draft unit positioned forwardly of the apron driving nip and above the apron to produce a restricted fiber passage, a positive driving element connected to the slip draft unit, said slip draft unit being adjustable both horizontally and vertically of said apron, said slip draft unit having firm end portions which may press on the apron to depress it under tension and aid in driving the apron, and a central fiber control portion, said central fiber control portion forming a curved slip draft passage with the apron for textile fibers being processed, said central fiber control portion being the only fiber control portion of the slip draft roll and being more readily deformable than the firm end portions which aid in driving the apron.

3. In a drafting device for textile fibers, a pair of front drawing off members forming a nip, stock feeding means including an endless looped apron rearwardly of the said nip, yieldable tensioning means for the apron, supporting means for'the apron, apron driving means, said driving means including a slip draft roll positioned close to the drawing 01f nip and being in pressure contact with the tensioned apron, said slip draft roll having firm end portions which contact the apron and aid in driving it and a central fiber control portion, said central fiber control portion being more subject to deformation than the end portions and comprising means secured within a recess between the apron driving end portions so that the fiber control portion may exert yielding fiber restraining forces including pressure of less than breaking force on the textile stock in order that either long or short fibers or combinations may be processed without excessive fiber breakage and without deleterious operating effect on the central fiber contacting control portions and means operatively connected to th slip draft roll to rotate it.

4. In a drafting device for processing various lengths of textile fibers, a pair of front drafting members forming a front drawing ofi nip, stock feeding means including an endless apron, a nose bar and apron tensioning means within the apron loop, a roller in contact with the apron, a pressur slip draft roll having an apron contacting portion which forms a firm apron driving nip with the said roller and a central fiber contacting slip draft control portion of more fragile construction with respect to deformation than the nip forming portion, said central fiber contacting slip draft control portion being substantially unaffected by pressure from the tensioned apron when textile stock is not being run through the drafting device, but responsive to apron pressure to compress strands of fibers during processing and driving means for the apron driving nip forming members.

5. In a drafting device for processing textile strands having a wide variation in fiber length, a pair of front drafting members forming a front drawing off nip, stock feeding means including an apron, a nose bar and tensioning means for the apron, a roller in contact with the apron, a pressure slip draft roll having an apron contacting portion to depress the apron into a curved path under tension and which forms a firm apron driving nip with the said apron contacting roller, said pressure slip draft roll having a central slip draft portion, extending to approximately flush with the nip forming portion but forming only a yielding restraint on the fibers being processed, said restraint being less than sufficient to break the fibers and driving means connected to the apron nip forming unit.

6. In a drafting device for textile fibers, a pair of front drawing off members forming a nip, stock feeding means including an endless looped apron, means closely rearwardly of the front drawing on, members for supporting the apron, rotatable means for forming an apron nip to drive the apron, said means including an apron driving roll within the loop of the apron and a portion of a slip draft unit superposed to the apron, said slip draft unit having end portions which cooperate with the said apron driving roll to form a driving nip for the apron and a central slip draft control portion, positive driving means connected to one of the apron driving nip forming rotatable members, said central fiber control portion comprising slip draft means inserted in a recess between the apron driving end portions so as to exert a yielding fiber restraining force on the fiber stock being processed in order that stocks containing fibers of a length considerably greater than the distance between the front nip and said driving nip may be processed without excessive fiber breakage.

7. In a drafting device for long and short textile fibers, a pair of front drawing off members forming a nip, stock feeding means including an endless looped apron, supporting and tensioning means for the apron, rotatable means positioned in the critical drafting zone close behind the front drawing off nip to drive the apron, said means including an apron driving roll within the loop of the apron and a portion of a slip draft unit superposed to the apron, said slip draft unit having end portions which form an apron driving nip with the said apron driving roll and a central slip draft fiber control portion, positive driving means connected to the apron driving means, said central slip draft fiber control portion comprising slip draft means positioned in a recess between the apron driving end portions :10 as to exert a slip pressure and intimate fiber control forces on the fiber stock being processed and said end portions providing a guard for the slip draft means.

8. In a drafting device for processing various lengths of textile fibers, a pair of front drafting members forming a front drawing off nip, stock feeding means including an endless looped apron, means for driving the apron, apron supporting and tensioning means positioned within the apron loop and in contact with the apron, a slip draft roll having firm collar portions which contact the apron, but not the fibers being processed, and a central slip draft control portion for contacting and controlling the fibers during processing, said central slip draft control portion being more readily deformable than the firm apron contacting portion and being protected by the firm collar portions against undesirable deformation. 9. In a drafting device for long and short textile fibers, a pair of front drawing off members forming a nip, stock feeding means including a short endless looped apron, supporting and tensioning means for the apron, rotatable means positioned in the drafting zone close behind the front drawing off nip to drive the apron, said means including a single apron driving roll within the loop of the apron and a slip draft roll superposed to the apron and centered forwardly of the apron driving roll, said slip draft roll having end portions which form an apron driving nip with the said apron driving roll and a central slip draft portion, said central slip draft portion comprising slip draft means positioned in a recess between the apron driving end portions so as to exert slip pressure and intimate fiber control forces on the fiber stock being processed and positive driving means connected to the apron driving means.

10. In a drafting device for textile fibers, a pair of front drawing off members forming a nip, means closely rearwardly of the front drawing off members for supporting the apron, rotatable means for forming an apron nip to drive the apron, said means including an apron driving r011 within the loop of the apron and a centrally recessed slip draft roll superposed on the apron, said slip draft roll having relatively firm end portions which cooperate with the said apron driving roll to form an apron driving nip for the apron and a central fiber contacting slip draft control portion, said central fiber contacting slip draft control portion comprising a slip draft means secured in the recess between the end apron driving portions of the slip draft roll, said means being more readily deformable than the relatively firm apron driving portions.

' 11. In the combination set forth in claim 10 further characterized in that the more readily deformable slip draft means are pins and that both pressure and intimate fiber control and 9 straightening of untwisted stock may be effected.

12. In a drafting device for long and short textile fibers, a pair of front drawing off members forming a nip, stock feeding means including an endless looped apron, supporting and tensioning means for the apron, rotatable means positioned in the drafting zone close behind the front drawing oif nip to drive the apron, said means including an apron driving roll within the loop of the apron and a slip draft roll superposed to the apron and centered forwardly of the apron driving roll, said slip draft roll having end portions which form an apron driving nip with the said apron driving roll and a central slip draft portion, said central slip draft portion constituting the fiber contacting and control part of the roll and together with the apron forming a slip draft passage for the fibers, said central slip draft portion. being more readily deformable than the end apron driving portions, and positive driving means connected to the apron driving means.

13. In the combination set forth in claim 10, further characterized in that the apron driving roll is formed like a spool and clearance is provided between the spool and the apron at that portion of the apron which is opposite the central fiber contacting slip draft control portion of the slip draft roll.

14. In a drafting mechanism for textile fibers, front and back rollers defining a drafting area, a movable supporting apron for the fibers as they pass longitudinallythrough said drafting area, said apron being positioned rearwardly of the front rollers, a pin roll combing member in running contact with said supporting apron, said pin roll member being driven by the supporting apron in its forward movement.

15. In the combination set forth in claim 34 further characterized in that the pin roll fiber controlling member is connected to a source of power other than the supporting apron.

16. In a drafting mechanism for textile fibers, front rolls forming a front drawing off nip, a movable supporting apron for said fibers, said apron being positioned rearwardly of the front rollers, tensioning means positioned partially within the confines of the apron, a pin roll combing member in pressure contact with the outer surface of said apron, said pin roll combing member cooperating with said tensioning means to introduce additional tension to the apron and to depress it into a curved path in the area of contact of the apron and pin roll.

17. In a drafting device having a drafting area for textile fibers, a pair of front rolls forming a front drawing ofi nip for textile fibers, a supporting apron for fiber stock passing through said drafting area, said apron being positioned rearwardly of the front rollers, means for frictionally driving said supporting apron, a roller for pressing on the surface of the fibers being drafted as they move between the roller and apron said roller having short pins for penetrating the stock and controlling the pressed fibers, and means other than the stock for driving said pressure roller at a predetermined rate.

18. In a drafting device having a drafting area for textile fibers, a pair of front rolls forming a front drawing oif nip for textile fibers, a supporting apron for fiber stock passing through said drafting area, said apron being positioned rearwardly of the front rollers, means for frictionally driving said supporting apron, a roller in the critical draft area for pressing on the surface of the fibers being drafted as they move between the roller and apron said roller having short pins for penetrating the stock and controlling the fibers being pressed by the surface of the roller and supporting apron and means for positively driving said pressure roller at a predetermined rate, regardless of the separation rate of the fibers being drafted.

19. In a drafting mechanism having a drafting area for textile fibers, a front pair of rolls which forms a front drawing off nip, a movable supporting apron for the fibers as they pass through the drafting area, said apron being positioned rearwardly of the front rollers, tensioning means including a weight roll and spring assembly for the supporting apron, a pin roll combing member inpressure and apron deflecting contact with the surface of said apron, said pin roll combing member cooperatingwith said tensioning means to produce tension and curvature in the apron in the critical draft area at the rear of the front pair of rolls.

20. In a drafting mechanism having a drafting area for textile fibers, a front pair of rolls to form a front drawing off nip, a movable supporting apron for the fibers as they pass through the drafting area, said apron being positioned rearwardly of the front rollers, a combing roller having collars, means for positively driving the combing roller and means forming a nip with a roller collar to create an apron driving means.

21. In a method of drafting textile fibers, the steps which consist of feeding a strand of fibers to and through a drafting area, providing a continuous support lengthwise of the fibers, simultaneously and progressively penetrating the strand of fibers being fed by inserting fiber control teeth the full width of the stock but only at points opposite to points of continuous sup-' port, withdrawing the fiber control teeth after substantially complete penetration of the stock, said insertions and withdrawals being in a rotary path, the outer perimeter of said rotary path of the fiber control teeth touching or being closely spaced from. the said points of support so that the initial penetration of the fibers is effected without substantial distortion of the strand by the teeth, and the fibers are controlled without localized strand deflections within the penetrated area. a p

22. In a method of drafting textile fibers having a wide variation in length, the steps which consist of feeding a stock of fibers to and through a drafting area, providing a continuous support lengthwise of the fibers in a predetermined position in the drafting area, simultaneously and progressively penetrating through the stock of fibers being fed by inserting and withdrawing fine fiber control teeth, said insertions and withdrawals being in a rotary path and the insertions being only at points opposite to points of continuous support, the outer edge of said rotary path of the fiber control teeth touching or being closely spaced from the points of support in the predetermined area so that the fine teeth will enter the stock without substantial compression or localized deflection of the fibers by the individual teeth and the support.

23. In the combination set forth in claim 21, further characterized in that the teeth are inserted at an angle to the fibers being fed whereby the drafting of the fibers will cause the fibers to move into the area of the teeth, and wild fibers will be controlled.

24. In a method of drafting textile fibers, 'thej steps which consist of feeding fibers to and through a drafting area, providing a continuous support lengthwise of the fibers for those fibers which have reached a forward portion of said drafting area in which the fibers are being rapidly moved relatively to one another, progressively inserting and withdrawing fine teeth through the stock from above the fibers, said insertions and withdrawals being in a rotary path and the insertions occurring only where the fibers are continuously supported against downward deflection at points which are at or closely spaced from the outside perimeter of the rotary'path of the penetrating ends of the fine teeth, moving the fine teeth and support simultaneously in the gen-' eral direction of stock travel while simultaneously feeding, drafting, and controlling the penetrated fibers so that the penetrated stock is uniformly controlled, and wild fibers are effectively prevented from leaving the mass of fibers in the said forward drafting area.

25. In the combination set forth in claim 21, further characterized in that the fibers being penetrated, confined against separation from the mass, and combed, are substantially simultaneously with these operations subjected to a top and bottom pressure and are caused to follow the rotary path of the teeth for a predetermined distance,

26. In a method of drafting textile fibers, the steps which consist of feeding fibers to and through a drafting area, providing a continuous support lengthwise of the fibers for those fibers which are being moved relatively to one another in the drafting area, progressively inserting and withdrawing groups of fine teeth from above the fibers, said insertion and withdrawal being in a rotary path and the insertions occurring only at points where the fibers are continuously supported against downward deflection from the mass of fibers along a path which contacts the penetrating ends of the fine teeth as they move through their rotary path, moving the teeth and contacting support simultaneously in the general direction of stock travel while simultaneously feeding, drafting, and combing the penetrated fibers whereby the penetrated stock is controlled and wild fibers are effectively prevented from leaving the mass of fibers in the said drafting area.

27. In a method of drafting twisted textile strands, the steps which consist of feeding fibers to and through a drafting area, removing the twist of th strand as it moves forwardly in the drafting area, providing a continuous support lengthwise of the fibers for those fibers or portions of fibers which have reached a forward portion of said drafting area in which the fibers are being rapidly moved relatively to one another, then progressively inserting and withdrawing groups of fine teeth from above the fibers, said insertion and withdrawal being in a rotary path and the insertions occurring only while the fibers are continuously supported by said support against downward deflection from the mass of fibers along a path which contacts or is closely spaced from the outside of the rotary path of the penetrating ends of the teeth. moving the teeth and support simultaneously in the general direction of stock travel while simultaneously feeding, drafting, and combing the penetrated fibers so that the penetrated stock is approximately uniformly controlled and wild fibers are effectively prevented from leaving the mass of fibers in the said forward drafting area.

28. In a drafting device for textile fibers, feeding means, means providing a front drawing of! nip for fibers being drafted, a fiber supporting guide means which extends lengthwise along the path of the fibers being processed as they move to the front drawing ofi nip, a rotatable fine tooth control roller, said control roller and said guide means defining a fiber passage which is substantially through the teeth of the control roller, and said guide means being in sufliciently close proximity to the ends of the teeth at the points of first contact between the teeth and strand of fibers being processed so that the initial point of penetration of the stock by the fine teeth is always opposite a point of support for the fibers. I

29. In a drafting device suitable for the drafting of textile fibers, means to provide a front drawing off nip for fibers being drafted, means for controlling the uniformity of the drafting, said means including a relatively smooth resilient supporting means, a rotatable finetooth control roller which, together with the resilient support defines a fiber control passage for the fibers to be drafted, said resilient support means being in contact with the fine tooth control roller, and positioned for supporting the stock as it approaches the ends of the teeth in order that penetration of the stock by the teeth is always affected directly opposite a point of support for the fibers, means for driving the resilient support, and means for driving the rotatable fine tooth control roller, whereby the fibers will be positioned within the area of the teeth during operation of the device by means of the coaction of the toothed roll and the uninterrupted surface of the resilient support without localized vertical deflection of the strand as it moves through the fine teeth.

30. In a drafting device suitable for the drafting of textile fibers, means to provide a front drawing off nip for fibers being drafted, means for controlling the fibers rearwardly of the front drawing off nip, said means including a movable apron for contacting the fibers as they pass toward the front nip, a rotatable control roller having penetrating pins closely superposed to said movable apron to form a fiber control passage which is substantially wholly within the pinned area of said roller, whereby a strand of fibers being processed will be confined within the zone of the penetrating pins without distortion of the strand within the pinned area.

31. In a drafting device suitable for the drafting of textile fibers means to provide a front drawing off nip for fibers being drafted, means for controlling the fibers rearwardly of the front drawing off nip, said means including a movable apron for contacting the fibers as they pass longitudinally toward the front nip, a rotatable pressure control roller having penetrating short pins closely superposed to said movable apron to form a fiber control passag which is substantially through the pinned area of said roller, whereby the strand of fibers being processed will be simultaneously pressed evenly across its width while confined within the zone of the penetrating pins without distortion of the strand in the pinned area.

32. In the combination set forth in claim 31, further characterized in that the pins are inserted in the control roller at an angle of such size that an obtuse angle is formed by the pins and the advancing fibers as these fibers initially contact the pins.

33. In a drafting device suitable for the drafting of untwisted or twisted textile fibers, means to form a front drawing off nip for the fibers, means for controlling the fibers during drafting, said means including a frictionally driven apron for supporting a strand of fibers as they move longitudinally toward the front nip, a rotatable control roller having fine teeth for penetrating through the strand positioned above the apron close to the front nip, said control roller and apron being in pressure contact with each other and forming a fiber control passage through the device, means for driving the rotatable pin roller and movable apron whereby a continuously fed strand of fibers will be positioned substantially within the area of the fine teeth during operation of the device.

34. In a drafting mechanism for textile fibers, front rollers which form a front nip to draw off the fibers as they are drafted, a movable supporting apron for fibers as they pass forwardly to the front nip, a rotatable pin roll fiber controlling member in running contact with the supporting apron and defining a fiber passage therewith, said pin roll having a surface speed equal to the surface speed of the supporting apron.

35. In a drafting mechanism for textile fibers, front rollers which form a front nip to draw off the fibers as they are drafted, a movable supporting apron for fibers as they pass forwardly to the front nip, a rotatable pin roll fiber controlling member for penetrating the supply of fibers as it moves forwardly along the apron and approaches the front nip of the drafting mechanism.

36. In a drafting mechanism for textile fibers, a front drawing ofi' means for the fibers, a movable supporting apron rearwardly of the front drawing off means, a rotatable pin roll combing member in pressure contact with the supporting apron and causing it to take a curved path, said pin roll combing member and apron forming a fiber passage for stock being fed and operating together at a predetermined surface speed for each.

37. In a drafting mechanism for textile fibers, front members which form a front nip to draw oil the fibers as they are drafted, a movable supporting apron for the fibers as they pass forwardly to the front nip, a vertically adjustable rotatable pin roll fiber controlling member for penetrating the supply of fibers as it moves forwardly along the apron and approaches the front nip of the drafting mechanism, a fixed bar support for the movable apron and stock, said fixed bar being positioned between the pin roll and the front members at a height which will deflect the stock in the opposite direction to the deflection caused by the vertically adjustable pin roll in different adjusted positions.

38. In a drafting mechanism for strands of textile fibers, a front drawing of! means forming a nip for fibers being drafted, a vertically adiustable rotatable pin roll close to the nip of the drawing 011' means, a flexible strand guide positioned close to the pin roll to support the strand directly opposite a point of initial strand penetration by the pins, a fixed bar between the pin roll and the drawing or: nip, said fixed bar being positioned at a height so as to provide a vertical deflection in the path of the strands as the strands move from the pin roll to the drawing ofl. nip in different adjusted vertical positions of the pin roll. said deflection varying d positioned close to the front in extent depending on the particular vertical position of the pin roll.

39. In a drafting mechanism for strands of textile fibers, a front drawing oif means having a nip for fibers .being drafted, a rotatable pin roll close to the nip of the drawing 011 means, a forwardly feeding guide means positioned sufiiciently close to the pin roll to support the strand directly opposite to a point of initial strand penetration by the pins, a fixed support bar positioned between the pin roll and the drawing off nip, said fixed bar being positioned at a height so as to provide a vertical deflection in the path of the strands as the strands move from the pin roll to the drawing off nip, said vertical deflection varying in extent in accordance with the particular vertical adjustment of the pin roll.

40. In a drafting device for textile fibers, feeding means, means providing a front drawing ofi nip for fibers being drafted, a guide means having a relatively smooth surface, said surface extending lengthwise the path of the fibers being processed as they move to the front drawing ofi nip, a single rotatable fine tooth control roller, drawing ofi nip, said control roller and said guide surface defining an elongated fiber passage which is substantially through the teeth of the control roller, and said guide surface being in close proximity to the ends of the teeth at the points of first contact between the teeth and stock being processed so that the initial point of penetration of the stock by the fine teeth is opposite a point of support for the fibers.

41. In a drafting device for textile fibers, feeding means. means providing a front drawing ofl. nip for fibers being drafted, a flexible support and guide means having a relatively smooth surface which extends lengthwise of the path of the fibers to be processed as they move to the front drawing off nip, a rotatable and adjustable fine tooth control roller, said control roller and flexible support defining a fiber passage in several adjusted positions, all of which are substantially through the teeth of the control roller, said flexible support being in close proximity to the ends of the teeth at points of first contact between the teeth and stock being processed, so that the initial point of penetration of the stock 0 by the fine teeth is opposite a point of support for the fibers.

WHITWORTH F. BIRD.

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

UNITED STATES PATENTS Number Name Date 461,855 Thompson Oct. 27, 1891 755,347 Bietenholz Mar. 22, 1904 849,812 Perrin Apr. 9, 1907 1,748,712 Gminder Feb. 25, 1930 1,795,351 Stell Mar. 10, 1931 1,933,222 Rooney Oct. 31, 1933 2,079,122 Lawton May 4, 1937 2,091,822 Kraft Aug. 31, 1937 2,233,963 Shaw Mar. 4, 1941 FOREIGN PATENTS Number Country Date 457,557 Great Britain Dec. 1, 1936 510,336 France Dec. 2, 1920 674,084 Germany Apr. 4, 1939

Images