US2916779A - keyser - Google Patents

Description

J. J. KEYSER Dec. 15, 1959 DOUBLE-BELT DRAWING UNIT FOR SPINNING MACHINES 3 Sheets-Sheet 1 Filed July 29, 1957 Fig. 2

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lNVENTOR Taba.nn Jieob a e/J A-w/ g .J. J. KEYSER Dec. 15, 1959 DOUBLE-BELT DRAWING UNIT FOR SPINNING MACHINES Filed July 29, 1957 3 Sheets-Sheet 2 INVENTO F? aann 3340197 6 J. J. KEYSER Dec. 15, 1959 DOUBLE-BELT DRAWING UNIT FOR SPINNING MACHINES Filed July 29, 1957 3 Sheets-Sheet 3 //v VENTOI? J2me b fyftr Pale United States Patent The present invention relates to improvements in apron drafting roller units for spinning machines, particularly for slubbing and finespinning machines.

It is well-known in the art of spinning that a fiber strand may be subjectedto an adequatebacking within the drafting unit if it is passedbetweentvvo endless revolving aprons, as is done, for example, in a Casablanca drafting frame of aknown design.

However, all of the known apron drafting units have the disadvantage that such retaining action is not uniformly exertedfuponall ofthefibers within the cross-sectional area of-a fiber strand. This is due to the factthat Although each of these two different trends of development led .to certain advantages, both of them had certain disadvantages. Even though no efforts have been spared in the past to overcome these disadvantages, these efforts have sofar been unsuccessful.

. It is the principal object of the present invention to provide a suitable apparatus which while combining the above mentioned two different principles and-advantages inherent thereto, will completely overcome their individual disadvantages.

According to the present inventiomthis object has been materialized by providing the lower and/or the upper guide rollers of the belts with at least one recess within the area of travel of the fiber strand. These recesses may be provided in the guide rollers in alternate succession of the latter, and either in'the guide rollers for only one apron or in the associated rollers of both aprons. They may also be providedin someof the associated rollers of both aprons, while in-others they may beentirely omitted.

Another feature of the invention consists in making the distance, the number, and/ or the weight of the guide rollersof each-drafting unit adjustable. All of the guide the fibers directly engaging with the two aprons are retained to a greater extent than those disposed at the in side of the beltsfandthat the inner fibers mightstart to float when the other fibers while being drafted are pulled out of the fiber. strand. This disadvantage becomes noticeable particularly if the floating fibers are considerably fabric will result. p

Many efforts have been made in the past to overcome shorter than the average staple so that an uneven yarn or these disadvantages of the known apron drafting units. These efforts progressed primarily in two differen t dixfections which tosome extent were opposed to each other and which maybe described as follows: f

(a) The drafting aprons are'exposed to considerable wear, the extent of which depends upon the material of which they are made, the type and quantity of the fibrous material being processed, and the pressure at which the aprons act upon each other and upon-the fiber strand between them. With three-roller draftingunits with double aprons it has, therefore, been tried to provide theguide rollers of the aprons underneath the path for the-fiber strand with a recess. This allows the aprons to form passages betweenithe pressurepoints which 'also permit longer fibers to be drafted properly without the danger that such fibers might break; This also increases the elasticyieldability"ofthe aprons,while reducing the wear of the aprons. Also a softer retaining action will be obtained which, however, is less than that produced by smooth rollers without such recess. A 5

(b) Independently of this procedure to protecting the material of the aprons, various attempts-have been rhade to improve the-retaining action, that is, to equalizeand increase such action, by passing the fibers through the drafting field not in" a straight direction but along a curved path so that the frictional retainingaction onthefapron the fibers 'inside the fiber strand. This is brought about will be increased by the looping angle thus formed.

Even the very first Casablanca drawing frame'provided for such deflection of the aprons and the path of travel of the .fibers. However, such a rigid defiecti o hbf the aprons between rollers involved considerable difilculties in that the aprons could not be made to run quietly, and that the repeated deflection between rigid rollers easily increased the retaining action to such an extent asto lead to a breaking of the fibers and, that last but not least; the aprons were WOl'l'litO aagraterextent than was warranted by suchincreased retainingraetion'. i i

rollers of one drafting unit may also be made either of thesame weight orof different Weights. --By means of the present inventon it is possible to attain advantages which previously were unattainable either in the manufacture of spinning "machines or in their operation any of the numerous branches: of thespinning n; i: i a

The present "invention permits a uniform manufacture of the individual parts of a drafting unit which will'be applicable in place of all other types of drafting units previously used and thus a universal application of such units to all types of fibers in the various branches of spinningfl p i In a view of the. great adaptability and operational flexibility: of the drafting unit according to the inventionawhich isdue to the adjustability of the distance between the guide rollers and the possibility of applying guide rollers eitherwith or without recesses, depending upon the type of fibrous material to be proc-' essed, the drafting'unit according to the invention may be" applied without difiiculty either for processing long staple fibers, for example, worsted, or-short staple fibers,

for example, East Indian cotton. This is due to the fact that, in accordance with the larger or smaller disguided in such a manner duringthe drafting of the individual=fibers that the short staple fibers will be prevented fiorh floating which considerably affects the quality of the spuniyarn. As a matter of fact, a floating of fibers in a drafting unit designed and properly adjusted according to the invention will be absolutely prevented since nolonger only the fibers directly engaged bythe aprons are subjected to a proper retaining action but also by the undulated back and forth movement of the fiber strand is. when due to this movement the crosssectional shape of the fiber strand is being changed between'two points ofpassage throughthe guide rollers which are provided with an upper or lower recess, respectively. In this way, it is also possible to exert a better retaining action upon short fibers than was previously attainable so' that the quality of the 'yarn will also be improved.

These and other advantages may be realiz ed particularly and in the most simple manner in wide-apron drafting units, that is, in units having revolving aprons which extend over several spinning stations and possi bly fromroller stand to roller stand. Such advantages could'not be attained by the use of wide-ribbon drafting units offprevious design. a

These and further objects, features, and advantages of the present invention will now be described in detail with reference to the accompanying drawings, in which- Fig. 1 illustrates a section of a drafting unit with a recessed guide roller according to the prior art;

Fig. 2 shows a diagrammatic side view of a part of a drafting unit according to the prior art, in which the material is drafted along a curved path;

Fig. 3 shows a partial perspective view of the guide rollers according to the present invention for use with a double apron;

Pig. 4 illustrates a cross section of a double-apron drafting unit according to the invention;

Fig. 5 illustrates a cross section of the same drafting unit as shown in Fig. 4, but with the pairs of cooperating guide rollers spaced differently from each other;

Fig. 6 shows a cross section of the same drafting unit as in Figs. 4 and 5.but a different arrangement of the rollers of each pairs of guide rollers; while Fig. 7 illustrates an arrangement which differs from that of Fig. 4 in that two grooved end rollers (directly preceding the delivery rollers not shown) are employed instead of one only.

Referring to the drawings inwhich similar parts are designated by the same reference numerals, Fig. 1 illustrates a grooved apron guiding roller as used prior to the invention. The lower guide roller 1 has a recess; or groove into which the belt can deflect, while the fiber strand passes through thedrafting area formed between the upper and lower aprons by means of the upper and lower guide rollers. v

' Fig. 2' shows the heretofore known manner of mount elastic flexibility and the deflection of the aprons, and no longer, as in the conventional drafting frames, by the amount of pressure of the upper apron upon the lower apron, that is, by the weight of the individual upper rollers, one spinning point can no longer be influenced by an adjacent spinning point. When previously several spinning points, particularly more than two, were loaded by one upper roller (either with or without an upper apron), and a thicker slubbing or sliver portion was drawn through the rollers at one spinning point, the other point at the same upper roller could be released so that the retaining action upon the fibers was also released atthispoint. The upper rollers have for this reason in the past been designed for no more than one or two spinning points, and it was therefore necessary also in wide-belt drafting'units to mount these upper rollers in special supports between the normal individual bearing supports. The present invention renders such intermediate supports unnecessary. Now, not only the lower guide rollers including the lower apron may extend from roller stand to roller stand and may be mounted therein or in common pivotable frames on said roller stands, since the new manner of guiding the aprons prevents the transmission of any influence from one drawing point to another due to the fact that a possible thicker slubbing or sliver .portion can only produce an increasing bulging of the apron at this particular spinning point but cannot result in a lifting of the upperroller. Furthering the guide rollers for the upper and lower aprons within the same horizontal plane. This results in a drafting field in which the fiber strand to be draftedis passed along a'curved path so that the. frictional retain ing force will ,be-increasedj. Figs. 3 and 4 illustrate the principle according to the present invention. Guide rollers 1, 2, 3, and 4 for the lower apron and the corresponding guide rollers 1, 2., 3', .and d for the upper apron have alternating recesses or grooves at the different spinning points. These grooves alternate both in .their horizontal succession as well as vertically between the associated upper and lower rollers. vThe width of the grooves substantially corresponds; to the Width'Of' the grooved rollers so that the transverse. motion of the apron being drawn into the apparatus can be retained in the usual form. For a-better illustration of the invention, the cross section according to Fig. 4 and the succeeding figures are taken through the grooved portion of the guide rollers. Fig. .4 illustrates the superimposed aprons as being rigidly sup ported in an alternating succession between the guide rollers only either at the upper or lower side, while at the' respective opposite side they are free and can deflect into the recesses.

By such an arrangement the followingadvantages will be attained:

1) The fibers will be subjected to a very soft elastic retaining action which is caused along the entire drafting length solely by the elasticity of the material of the aprons;

more, it is no longer necessary toapply several upper loadrollers of different weights in accordance with the material to be processed but, generally speaking, the rollers may all. beof, equal weight since the control of the retaining force will be 'attainedby the number of or the distance between the guide rollers. Also, any changes in thedimensions tO'WhlCh the apronsmight, be subjected after. acertti'nlength of timeofoperation, for example, by swelling, and their effect upon the spinning process will be alleviated by the new manner of guiding the aprons.

The location and depth of the recesses within the individual upper or lower guide rollers may be varied in many different ways. Thus, for example, if desired, the recesses may be entirely omitted in some of the associated pairs of rollers, for example, in the very first pair of rollers 1, 1', and they may be provided only in the following pairs.

Such modifications are illustrated in Figs. 5 to 7 in similar crosssections as shown in Fig. 4.

Fig. 5, shows thelower guide roller 1 adjacent to the spinning roller as Well as the upper guide roller 1' as being without any recesses or grooves, while the lower guide rollers land 4 and the upper guide roller 3' are each provided with a recess or groove. Furthermore,

(2) The aprons andthus also the fiber-strandsare subjected to an undulated, soft deflection so that-'the fibers will be uniformly embedded within the resilient material of the aprons throughout the entire drafting field;

which means that the retaining action will be entirely,

uniform as well as increased because atthe moment of deflection, i.e. when the fiber strandchanges over, for

example, from the lower to the upper embedding POSi provided with grooves.

the distances between theindividual guide rollers are made smaller than those shown in Fig. 4 so that a drafting unit of this kind may also be used for drafting fiber strands with short staple fibers.

According to Fig. 6, the first guide rollers. 1 and 1' are likewise without grooves, while the succeeding lower guide roller 3 and the upperguide rollers 2 and 4' are The distance between the. individual guide-rollers is still less thanin Fig. 5. Furthermore, this, drafting unit includes another non-grooved pair of; guide rollers 6 and 6-which forms the rear end of the drawingarea so that this arrangement of the draftingunitwill be suitable for processing short fibers.

Fig. 7 shows an arrangement substantially similar to that of Fig.- 4, except for the fact that the two first guide rollers; 1 and 1' are provided with grooves. Such roller arrangement is suitable particularly for drafting very longstaple fibers, and' it is thus no longer necessary to provide a special machine which is designed exclusively for drafting such long fibers.

Theabove examples also showthat numerous variations in the relative arrangement: of the. guide rollers may be attained by employing guide rollers of different diameters. The distance between the rollers may be adjusted in any convenient manner for instance in the manner shown in U.S. Patent No. 1,644,747 or U.S. Patent No. 2,741,801.

In this manner it is possible to employ a drafting unit of a single basic design for various branches of spinning and for all types of fibers to be processed inasmuch as it is very simple to adapt the drafting unit to the respective purpose by merely changing the relative position of the guide roller pairs with regard to each other or the number of guide roller pairs, and/or the diameter of the guide rollers, since the possibilities of variation are so numerous as to permit any variations of such drawing units in accordance with the type of fibers used.

Although my invention has been illustrated and described with reference to the preferred embodiments thereof, I wish to have it understood that it is in no way limited to the details of such embodiments, but is capable of numerous modifications within the scope of the ap pended claims.

Having thus fully disclosed my invention, what I claim 1. A drafting unit for spinning machines, which includes: an upper apron, a lower apron for cooperation with said upper apron, and more than two pairs of mating guide rollers with one guide roller of each pair of guide rollers located in said upper apron and the other guide roller of each pair located in said lower apron, said pairs of guide rollers being arranged one behind the other in spaced relationship to each other, each of at least two successive pairs of said pairs of mating guide rollers being composed of a grooved guide roller in one of said aprons and a mating roller with a continuous cylindrical surface extending over the width of said aprons located in the other apron, the grooves of said grooved rollers being located within the respective apron intermediate the side edges thereof, the arrangement being such that the grooved rollers of said successive pairs of rollers are alternately located within said upper apron and said lower apron respectively.

2. A drafting unit for spinning machines, which includes: an upper apron, a lower apron for cooperation with said upper apron, more than two pairs of mating guide rollers with one guide roller of each pair of guide rollers located in said upper apron and the other guide roller of each pair located in said lower apron, said pairs of guide rollers being arranged one behind the other in spaced relationship to each other, each of at least two successive pairs of said pairs of mating guide rollers being composed of a grooved guide rollers in one of said aprons and a mating roller with a continuous cylindrical surface extending over the width of said aprons located in the other apron, the grooves of said grooved rollers being located within the respective apron intermediate the side edges thereof, the arrangement being such that the grooved rollers of said successive pairs of rollers are alternately located Within said upper apron and said lower apron respectively, and an additional pair of mating rollers arranged as end rollers of and within said upper and lower aprons respectively, each of the rollers of said additional pair of mating rollers being grooved, the grooves of all of said rollers being located at a point within the width of said aprons.

3. A drafting unit for spinning machines, which includes: an upper apron, a lower apron for cooperation with said upper apron, more than two pairs of mating guide rollers with one guide roller of each pair of guide rollers located in said upper apron and the other guide roller of each pair located in said lower apron, said pairs of guide rollers being arranged one behind the other in spaced relationship to each other, each of at least two successive pairs of said pairs of mating guide rollers being composed of a grooved guide roller in one of said aprons and a mating roller with a continuous cylindrical surface extending over the width of said aprons located in the other apron, the grooves of said grooved rollers being located within the respective apron intermediate the side edges thereof, the arrangement being such that the grooved rollers of said successive pairs of rollers are alternately located within said upper apron and said lower apron respectively, and an additional pair of mating rollers arranged as end rollers of and within said upper and lower aprons respectively, each of the rollers of said additional pair of mating rollers having a continuous cylindrical surface extending from one side of said aprons to the opposite side thereof.

References Cited in the file of this patent UNITED STATES PATENTS 1,644,747 Roth Oct. 11 1927 2,255,821 Schlipp et a1 Sept. 16, 1941 FOREIGN PATENTS 741,449 Germany Nov. 11, 1943

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