US3370326A

US3370326A - Method and apparatus for forming a web of highly parallelized textile fibers

Info

Publication number: US3370326A
Application number: US488370A
Authority: US
Inventors: Marvin A Law
Original assignee: Fieldcrest Mills Inc
Current assignee: Fieldcrest Mills Inc
Priority date: 1965-09-20
Filing date: 1965-09-20
Publication date: 1968-02-27
Anticipated expiration: 1985-02-27
Also published as: GB1157014A; DE1510252A1

Description

Feb, 27, 196 8 M /\v LAW 3,370,326

METHOD AND APPAFAQGI: FOR FORMENG A WE OF HIGHLY PARALLEL-Elli?) TEXTILE FIBERS 2 Sheets-Sheet 1 Filed Sept. 20, 1965 INVENTOR. MAYZ\/\N A. LAW

ATTORNEYS Feb. 27, 1968 M. A. LAW 3,370,326

APPARATU OR PARA D T RMENG A WEB ILE FIBERS 2 Sheets-Sheet 2 METHOD AND S F OF HIGHLY LLELIZE Filed Sept. 20, 1965 INVENTOR. MARVIN A. LAW

ATTORNEYS ABSTRACT on THE DISCLOSURE r A 'method'and apparatus of obtaining high parallelization of textile fibers in a web coming from a doffer cylinder of a carding machine wherein the web is detached from the doffer cylinder and passed through the nip of a pair of drafting rolls at a linear speed considerably in excess of the surface speed of the doffer cylinder to impart draft to the web and parallelization to the fibers thereof, and wherein a combing action is imparted to the web prior to passage through the nip of the drafting rolls to increase the parallelization of the. fibers thereof by engaging the web with a slower moving toothed surface at such a location that the trailing ends of fibers of at least average staple=length are engaged by the toothed surface while their leading ends are passing through the nip of the drafting rolls.

This invention relates to the art of carding textile fibers, and it is an object of this invention to provide an improved method and apparatus for producing a card web wherein most of the fibers are arranged in a more parallel condition in the machine direction than has been attainable heretofore to my knowledge.

Heretofore, the parallelization of fibers has been largely effected subsequent to condensing the web into a ropelike structure or sliver on a carding machine, with very little parallelizing and straightening of fibers being effected during the carding operation, and wherein the sliver was processed by' combing, multiple gilling or other multiple processes of drafting with fiber control. The parallelization of the fibers of a card web is highly desirable because there are-instances in which uncondensed card webs are use'dfor various purposes, such as in making non-woven fabrics or for forming the same into rovings on a tape condenser. Also, once a normal card web has been con densed intoasliver, subsequent drafting, gilling or combing results an undesirable degree of broken fibers. Further, the combing of such sliver results in an abnormal removal of waste therefrom due to hooked fibers.

An uncondensed card web is in an ideal condition for parallelizing the fibers thereof, because the web more nearly approaches single-fiber thickness as it comes from the doffer cylinder than it does in any subsequent production condition, thus presenting a minimum of resistance to alignment of the fibers in the web so hooks may be easily removed from the fibers with a minimum of fiber breakage. a

While it is'known to draft a fibrous card web in its course from the dofier cylinder, as in Vargas US. Patent No. 3,003,195-for example, the method and apparatus of this invention not'only subjects the web to a longitudinal draftingand parallelizing action, but applies a further cooperating parallelizing action to the web being drafted at an area a lesser distance from the area at which the draftinducing pulling force is applied to the web than the average staple length of the fibers being drafted so as to more highly parallelize the fibers throughout the web.

It is a more specific object of this invention to provide a novel method and means for dofling or detaching a web of fibers from the doffer cylinder of a carding machine while aligning and parallelizing the fibers, wherein a continuous, moving, toothed surface, embodied herein in a combing roll covered with garnett wire or saw-toothed metallic clothing, detaches or receives the card web directly from the doffer cylinder and then the web passes through the nip of a pair of drafting rolls whose surface speeds are considerably greater than the surface speed of the toothed surface and wherein the nip of the drafting rolls is spaced a lesser distance from the point at which the web is withdrawn from between the teeth of the garnett wire or toothed surface than the average staple length of the fibers in the Web so the teeth comb the fibers and hold them back as they are drafted between the toothed surface and the drafting rolls so as to highly parallelize the fibers, after which the web is Wound into a convolute roll rotating at a surface speed complementing that of the drafting rolls.

Some of the objects of the invention having been stated, other objects will appear as the description proceeds, when taken in connection with the accompanying drawings, in which- FIGURE 1 is a partially schematic and partially crosssectional view of one representative embodiment of the invention;

FIGURE 2 is an enlarged view of the web detaching and par-allelizing elements defined 'within the broken-line area 2 of FIGURE 1;

FIGURE 3 is an enlarged fragmentary view of the garnett wire clothing within the area 3 of FIGURE 2 and showing a portion of the associated web detaching and combing roll; and

FIGURES 4 and 5 are views similar to FIGURE 2, but showing two additional representative embodiments of the invention.

Referring more specifically to the drawings, the numeral 11 designates a driven main cylinder or swift of a carding machine and from which a web W of carded textile fibers is transferred to a dofier cylinder 12 which may be conventional and whose periphery is covered with metallic saw-tooth card clothing or garnett wire 12a whose points are shown facing in the direction opposite from the directionof rotation of doffer cylinder 12.

In order to remove web W from dofter cylinder 12 and to parallelize the fibers without necessarily condensing the web into a sliver, the first embodiment of the novel apparatus comprises a web detaching and combing element or roll 13 and a pair of upper and

lower drafting rolls

14, 15 which direct the web W to a take-up-roll 20 driven by a pair of spaced substantially parallel package supporting auxiliary take-up rollers 21, 22 to form a convolute web roll or package P. Detaching roll 13 is provided with garnett wire or metallic saw-tooth clothing 13a, each tooth of which preferably has a back-angled leading edge facing toward the direction of rotation of detaching roll 13.

As shown in FIGURE 3, the leading edge of each tooth of the garnett wire 13a preferably extends inwardly at an angle of up to about 20 back-slant with respect to a corresponding radius line extending from the axis of detaching roll to the apex of the corresponding tooth. In other words the narrow or leading edge of each tooth extends from its root upwardly to its apex at a back angle. The angle of the back edge of each tooth may vary according to the number of teeth per inch and the height of each tooth. These tooth angles have produced the most favorable'res'ults, but are exemplary only and are not to be considered as limiting characteristics of the teeth. The height of each tooth from its root to its apex may be about inch.

Detaching roll 13 should be located in such relation to dofier cylinder 12 as to detach the web therefrom and 3 the surface speeds of doffer cylinder 12 and detaching roll 13 should be about the same. In practice, in processing acrylic fibers of about 4% inches average'staple length, for example, to produce a web W weighing about 0.35 ounce per square yard, the surface speed of doffer cylinder 12 was about 5% to faster than that of detaching roll 13 with a minimum clearance of about .607 of an inch between doifer cylinder 12 and detaching roll 13. Now, in order to parallelize the web W, the web is drafted and combed simultaneously thereby straightening and aligning the fibers in the card direction. To this end, the periphery of bottom drafting roll 15 may be fluted to form closely spaced ridges 15a throughout at least as much of the length thereof as is engaged by web W and is positioned in sufiiciently close proximity to the garnett wire 13a on detaching roll 13 to insure that the web is embedded between the annular rows of teeth on the roll 13 immediately before the web is dislodged or pulled tangentially from between the teeth by drafting

rolls

14, 15, the surface speed of which is greater than that of detaching roll 13. This arrangement causes the fibers to engage a substantial portion of the periphery of detaching roll 13 so the fibers are pulled past the teeth of garnett wire 13a and thereby combed by the pulling force exerted on the web by the

drafting rolls

14, 15.

To insure further that the fibers are maintained in engagement with garnett wire 13:: beneath detaching roll 13, a small web-supporting roll may be located adjacent and beneath the lowermost portion of detaching r01 13. Roll 25 may be a smooth-faced steel roll and may or may not be rotatable. In practice, roll 25 was stationary and its upper surface wasspaced about of an inch from the clothing 13a on roll 13. In a typical installation, the

rolls

13, 14, 15, 25 were about 3 4 /2, 5, and 7 inches in diameter, respectively, although their diameter and relative positions may vary in different installations provided that the distance between the nip of

rolls

14, 15 and the point at which the webleaves roll 13 is less than the average staple length of the fibers in the web. The relative proximity of

rolls

13, 15 and the support of the web effected by roll 25 make the apparatus self-threading. In this regard, it should be noted that, upon initial detachment of the web from the dotfer cylinder, the web clings to garnett wire'13a and its support is assisted by roll 25. Thereafter, the web drops away from garnett wire 13a onto fluted roll 15 which, in turn, carries the leading portion of the web to the nip of

rolls

14, 15. In order to pull the fibers through the teeth of garnett wire 13a, the surface speed of

drafting rolls

14, 15 is substantially greater than that of detaching roll 15, as heretofore stated. While some parallelizing of the fibers may occur solely as a result of pulling the web relative to garnett wire 13a, this does not, of itself, straighten particularly curly or'kinky fibers. Therefore, an additional important feature of this invention resides in the fact that the distance from the nip or juncture of the

drafting rolls

14, 15 to the point of tangency of the fibers leaving the points of the teeth of garnett wire 13a is less than the average staple length of the fibers in web W so the trailing portion of each of most of the fibers is being drawn between the teeth of garnett wire 13a while the leading portion thereof is gripped between and being advanced by the drafting rolls, to effect a slip draft to the fibers. In practice, it has been found that the larger the diameter of roll 13 and its clothing 13a, the closer web-supporting roll 25 should be located to roll 13. Also websupporting roll 25 may be located at increased distances away from roll 13, especially if the distance from the nip of

rolls

14, 15 to the

nipof rolls

13, 25 is less than the staple length of the fibers in web W. It follows therefore that the desired support to be obtained by websupporting roll 25 can best be determined empirically.

The amount of draft imparted to the web is preferably in the range of from about 1.5 to 3.0 or more; i.e., the surface or angular speed of

drafting rolls

14,15 is prefthat the maximum draft is dependent upon the amount of fibers which may be carried by doffer cylinder 12.

To further insure ample traction between

drafting rolls

14, 15, top drafting roll 14 may be in the form of a metal core or shaft provided with a resilient cover 14a of natural or synthetic rubber, cork or the like. Since Web W may be as much as inches or more wide, the top drafting roll 14 may be of sufiicient weight to provide the desired degree of tractionto web W upon bottom drafting roll. If desired, however, suitable weights or fluid pressure means, represented by the arrow 14b, may be used for applying downward pressure to roll 14 toward roll 15. Drive means (not shown) is provided for cylinders 11, 12 and rolls 13, 14, 15 with arrows'a-e in FIG- URES l and 2 indicating the respective directions of rotation thereof. Top drafting roll 14 may be driven independently of and in synchronism with fluted 'roll 15. Generally, however, roll 14 is driven by contact with roll 15 or by the stock passing between

rolls

14, 15.

The apparatus thus fardescribed effects a very high degree of parallelization of the fibers in Web V1 as compared to that of card webs processed by knownmethods. I have found that the straightening and parallelizing of the fibers may be further improved by brushing the fibers While they are still on the doffer cylinder 12. To this'end, there will be observed in FIGURE 1 a driven rotary brush 27 which rotates at a surface speed considerably greater than and in the opposite direction from dofier cylinder 12. In other words, the proximal portions of brush 27 and doffer cylinder 12 move in the same direction. Brush 27 may be provided with easily bendable bristles of wire, nylon, or any desired material and is located in close proximity to dolfer roll adjacent and downstream of the fiber transfer region between cylinders 11, 12. In this instance, rotary brush 27 is shown positioned between the arcs of cylinders 11, 12 below the fiber transfer region or juncture thereof. Since the surface speed of brush 27 is considerably faster than that of cylinder 12, brush 27 lays down the surface fibers on the doffer to improve the effec tiveness of the controlled drafting system heretofore described in straightening and parallelizing the fibers. It is contemplated that dofier cylinder 12 may rotate in the same direction as main cylinder 11 and in the opposite direction from that of detaching roll 13 with the teeth 12a pointing toward their direction of rotation, without departing from the spirit of the invention.

In the second embodiment, with the exception of the clothing covered or garnett wire covered web-supporting roll 25 of FIGURE 4, the remaining rolls shown therein are substantially the same as the rolls of FIGURE 2 and, accordingly, the same reference characters will apply to both FIGURES 2 and 4 with respect to similaroridentical elements. In the second embodiment, the garnettwire covered roll. 25 is substituted for the roll 25 of FIGURE 2 and may be of somewhat larger diameter than roll 25; Roll 25' may be driven in a clockwise direction, as represented by the arrow thereon, so that the proximal portions of the clothing 13a, 25a on

rolls

13, 25 move in the same direction and at the same surface speed. The garnett wire 25a may be identical to garnett wire 13a (FIGURE 3) with the teeth thereof preferably having their narrow edges pointing toward the direction of rotation of roll 25'; i.e., toward the direction in which the web W is advanced. The proximity of garnett wires 12a, 25a (FIGURE 4) may be such that both rolls 13, 25 of FIGURE 4 contribute to the parallelizing and combing of the fibers in their course from dotfer cylinder 12 to drafting rolls 14, 15 in FIGURE 4. It is thus seen that the web W may be combed from both sides thereof.

The embodiment of FIGURE 5 includes the dofier cylinder 12 with its clothing or garnett wire 12a and also includes

rolls

13, 14, 15 which may be identical to those of FIGURES 2 and 4. Therefore, the same reference characters shall apply to like parts in FIGURE 5. The embodiment of FIGURE 5 differs from those of FIG- URES 2 and 4 in that the detaching and combing element or roll 13 rotates in a clockwise direction in FIGURE 5 instead of in a counterclockwise direction as shown in FIGURES 2 and 4. Accordingly, a conventional oscillating dofier comb 30 may be positioned as shown in FIG- URE 5; i.e., closely above or subsequent to the web detaching and combing roll 13 with respect to the direction of rotation of doffer cylinder 12, for detaching the web from dofier cylinder 12 so that it may be picked up by or deposited upon detaching roll 13. In so doing, it will be observed in FIGURE 5 that the web W passes over detaching roll 13, instead of passing underneath the same as is the case in FIGURES 2 and 4, and then passes downwardly through the nip of the drafting rolls 14, 15. Since the construction and operation of dolfer combs are well known, a further description and illustration thereof is deemed unnecessary. If desired, a roll similar to roll 25 (FIGURE 2) may be positioned above roll 13 in the embodiment of FIGURE 5 to assist in laying web W on roll 13.

In all the described embodiments, it is to be noted that the distance between the nip of the

rolls

14, 15 and the point at which the web leaves the preceding detaching and combing roll 13 is always less than the average staple length of the fibers in web W, and that the surface speed of the drafting rolls 14, 15 is always greater than the surface speed of detaching roll 13.

Although the detaching and combing element 13 is illustrated, in each instance, as a roll covered with garnett wire, as is preferred, it is to be distinctly understood that other types of web-detaching and combing elements or combinations thereof may be used without departing from the spirit of the invention. For example, a pair of cooperating endless fiber control aprons, one or the other or both of which have radially projecting pins thereon, may be used.

Although the desirable positive combing action may not be effected on the web, it is contemplated that a smooth-faced slip roll or smooth-faced endless fiber control aprons or the like may be substituted for roll 13, along with a suitable dofiing means, such as a reciprocating doflfcr comb, so as to apply a slip draft to the fibrous web as it is advanced between

rolls

14, 15. In any event, it is important that the combing and/ or drafting of the web W takes place adjacent to and following detachment of the web from the doffer cylinder, since the web more nearly approaches single-fiber thickness at this region than it does in any subsequent processing, thus offering less resistance to the straightening of individual fibers and to the parallelization of the fibers in the web with a resultant minimum of fiber breakage.

From the foregoing description, it is apparent that the drafting rolls 14, 15 apply a sufiicient pulling force to and throughout the width of the web in a forward direction to impart a longitudinal drafting and parallelizing action to the web while the web is being detached from the doffer cylinder 12 by the detaching roll 13 and/or the doffer comb 30 (FIGURE 5) and, at the same time, the detaching roll 13 applies a further cooperating parallelizing action to the web being drafted at an area a lesser distance from the area at which the pulling force is applied than the average staple length of the fibers being drafted and throughout the width of the Web.

Important advantages result from parallelizing the fibers in web W to the high degree possible in practicing this invention. For example, tape robbing is minimized in processing long staple fibers, such as synthetic and wool fibers for carpet yarns, according to the woolen system, and the resulting yarns contain a greater proportion of long fibers, resulting in a minimum of shearing machine and brushing machine waste. Also, in instances in which the highly parallelized web is subsequently condensed into a sliver, the shedding of waste therefrom in subsequent processes, such as combing, is considerably reduced. Further, the-highly parallelized fibrous web made according to the present method may be rolled up tightly ina roll or"lap that may be easily unwound without adjacent convolutions thereof having become so co-mingledr or married as to tear the web. The winding and unwinding of the web without tearing the same is' of considerable advantages in the process of arranging fibrous webs in superposed relationship as in making non-woven fabrics of unspun fibers.

In the drawings and specification there have been set forth preferred embodiments-of the invention and, although specific terms are employed, they are used in a generic and descriptive sense onlyiand not for purposes of limitation, the scope of the invention being defined in the claims.

I claim:

1. A method of obtaining high parallelization of textile fibers in a web coming from a doffer cylinder of a card ing machine, said method comprising detaching the web from the doffer cylinder and passing the web through the nip of a pair of drafting rolls at a linear speed considerably in excess of the surface speed of the dofier cylinder to impart draft to the web and parallelization to the fibers thereof and while applying a combing action to the web prior to passage through the nip of the drafting rolls by engaging the web with a slower moving toothed surface between the dolfer cylinder and drafting rolls at such a location that the trailing ends of fibers of at least average staple length are engaged by the toothed surface while their leading ends are passing through the nip of the drafting rolls whereby the fibers are highly parallelized.

2. A method according to claim 1 including applying a longitudinal brushing action to the web on the doffer cylinder prior to detaching the web therefrom to impart parallelization to the fibers thereof.

3. A method of obtaining high parallelization of textile fibers in a web coming from a dofler cylinder of a carding machine, said method comprising doifing and initially moving the web away from the dotfer cylinder at a linear speed substantially the same as the surface speed of the dofi'er cylinder, and passing the dofied web through the nip of a pair of drafting rolls at a linear speed considerably in excess of the surface speed of the dolfer cylinder to impart draft to the web and parallelization to the fibers thereof while applying a combing action to the web prior to passage through the nip of the drafting rolls by engaging the web with a slower moving toothed surface between the dolfer cylinder and drafting rolls at such a location that the trailing ends of fibers of at least average staple length are engaged by the toothed surface While their leading ends are passing through the nip of the drafting rolls whereby the fibers are highly parallelized.

4. A method of obtaining high parallelization of textile fibers in a web coming from a doffer cylinder of a carding machine, said method comprising detaching the web from the doffer cylinder by moving a toothed surface at a surface speed substantially the same as that of the doffer cylinder closely adjacent the dofi'er cylinder, while drawing the web away from the toothed surface through the nip of a pair of drafting rolls at a substantially greater linear speed than the surface speed of said toothed surface to impart draft to the web and parallelization to the fibers thereof and while applying a combing action to the web prior to passage through the nip of the drafting rolls by engaging the trailing ends of fibers of at least average staple length with the toothed surface while their leading ends are passing through the nip of the drafting rolls whereby the fibers are highly parallelized.

5. Apparatus for parallelizing textile fibers in a card Web while removing the web from a rotating doffer cylinder, comprising a rotating web detaching roll covered with garnett wire clothing, a pair of drafting rolls spaced forwardly of and rotating at a substantially greater surface 1 7 speedthan that of said detaching roll with the nip of the drafting rolls being located closer to the point at which the web leaves the detaching roll than the average staple length of the fibers in the Web, said detaching roll being 8 References Cited UNITED STATES PATENTS 11/ 1927 Laurency 19106 6/ 1932 Laurency 19-106 12/1964' Reiterer 19-106 2/1966 Reiterer 19-106 11/1966 Kalwaites 19,-106 11/1966 Kalwaites 19--106 FOREIGN PATENTS 8/1956 France.

1887 Great Britain. 11/1963 Great Britain.

15 DORSEY NEWTON, Primary Examiner;