US3457596A - Fiber drafting and blending system - Google Patents

Description

July 29, 1969 J. R. WHITEHURST FIBER DRAFTING AND BLENDING SYSTEM 5 Sheets-Sheet 1 Filed May 4, 1967 INVENTORZ AORNEYS july 29, 1969 J. R. WHITEHURST 3,457,595

FIBER DRAFTING AND BLENDING SYSTEM 5 Sheets-Sheet 2 Filed May 4, 1967 INVENTOR;

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ATTORNEYS July 29, 1969 J. R. WHITEHURST FIBER DRAFTING AND BLENDING SYSTEM Filed May 4, 1967 5 Sheets-Sheet 5 I NVENTOR.

ATTORNEYS July 29, 1969 J. R. WHITEHURST FIBER DRAFTING AND BLENDING SYSTEM 5 Sheets-Sheet 4.

Filed May 4, 1967 90% elk-v INVENTOR.

ATTORNEYS July 29, 1969 J. R. WHITEHURST FIBER DRAFTING AND BLENDING SYSTEM 5 Sheets-Sheet 5 Filed May 4 1967 mT I H E w H w DRv J A BYbdm, Wlwwl ATTORNEYS United States Patent 3,457,596 FIBER DRAFTING AND BLENDING SYSTEM Joe R. Whitehurst, Kings Mountain, NC, assignor, by mesne assignments, to The Warner & Swasey Company, Cleveland, Ohio, a corporation of Ohio Continuation-impart of application Ser. No. 565,580, July 15, 1966. This application May 4, 1967, Ser. No. 636,169

Int. Cl. D01h 5/00 U.S. Cl. 19243 4 Claims ABSTRACT OF THE DISCLOSURE A row of side-by-side primary drafting units are arranged to deliver respective textile webs of different types of fibers to a common conveyor means where they are superimposed and directed to a common processing machine or secondary drafting unit, and wherein all the drafting units and the conveyor means are driven by a common prime mover, with means interconnecting the primary drafting units and the prime mover in such a manner as to permit correlating the speed of delivery rolls of different primary drafting units relative to each other to obtain substantially the same rate of delivery of the webs therefrom to compensate for inherent differences in the delivery rate of different types of fibers.

This application is a continuation-in-part of my copending US. application Ser. No. 565,580, filed July 15, 1966, and entitled Method and Apparatus for Blending Textile Fibers.

This invention relates to the art of blending masses of textile fibers by drafting the same wherein the masses may differ from one another by having fibers of different lengths and/or kinds or, in the case of cotton fibers, they may come from different bales or from different areas of the world. As regards the kinds of fibers, they may differ as to physical characteristics and may include animal fibers, natural or man-made cellulosic fibers, mineral fibers and/or synthetic fibers; i.e., any textile fibers capable of being drafted and blended according to the instant invention.

Textile machinery capable of drafting simultaneously and independently a number of separate masses of like textile fibers as webs and superimposing said webs and delivering the same to a common winding machine or other processing machine is generally known. Ribbon lap and sliver lap machines are typical of such machinery. US. Patent No. 3,013,313 of Catling et al., issued Dec. 19, 1961, also is representative of various patents embodying this principle.

Until recently; i.e., prior to the development of the method and apparatus disclosed and claimed in my said copending application, the blending of masses of different types of fibers effectively on a single machine by drafting was impracticable because each primary or breaker drafting unit in a row must be capable of individual adjustment to accommodate staple fibers of different average lengths at different times, to impart different amounts of draft to different masses of fibers at different times, and to compensate for well known inherent differences in the delivery rate of different types of fibers consequent to differences in the traction or slickness between the fibers and the rolls of respective drafting units so as to impart substantially the same delivery rate to the webs emerging from all the primary drafting units in a row, All of these conditions are satisfied to a substantial degree in the ap paratus of my said copending application which is pri-- marily directed to the use of primary or breaker drafting, units having fluted intermeshing delivery rolls generally known as metallic rolls.

Patented July 29, 1969 Usually, in a metallic roll type of drafting unit, all the pairs of drafting rolls are metallic; i.e., they are of the intermeshing fluted type. Many drafting units, which may be termed as cushion roll type drafting units, are equipped with a smooth-faced or cushion top delivery roll and a fluted bottom delivery roll. At least the No. 2 top roll; i.e., the top roll immediately rearward of the delivery rolls, of a cushion roll type drafting unit is also a cushion roll resting upon a fluted roll, and the remaining top rolls preferably are metallic, but may be either metallic or cushion type rolls.

As is generally accepted, better processing results in utilizing intermeshing metallic drafting rolls where the stock being produced is of standard or relatively heavy weight. This is especially true with most all synthetic fibers except the fine denier fibers, since the intermeshing fluted rolls permit obtaining the desired control engagement of the fibers during the drafting thereof. Additionally, the delivery rolls result in imparting desirable crimp to the synthetic fibers which aids in further processing thereof by enhancing the cohesiveness of the fibers relative to each other. On the other hand, where the stock being produced is of relatively light weight or is of fine denier fibers or combed stock, it is accepted that cushion top rolls are most desirable, at least at the front portion of the drafting unit, for obtaining the proper engagement and control of the fibers. Thus, it is readily apparent that in a blending system it is most desirable, if not imperative, that the system lend itself for utilizing at any given time either or both types of drafting units in order to enable the system to properly produce any desired type of blend.

Some mills would prefer to use metallic roll drafting units but to eliminate the necessity for changing the extent of intermeshing relationship of fluted delivery rolls to effect desired changes in delivery speed of primary drafting units of a blending system. Also, other mills, irrespective of whether or not metallic roll type units may produce a better quality product from the particular textile material to be drafted, are Wedded to cushion roll type drafting units. Thus, these additional considerations point up the desirability of being able to utilize either type of drafting unit to satisfy customer requirements.

It is desirable to provide separate means for advancing the web from each of the successive primary drafting units to obtain the desired tension draft in each individual web in accordance with the dictates of the characteristics of the fibers forming the same. Further, it is desirable to advance the webs along the row of primary drafting units and to the common processing unit without affecting the tension draft being applied to the individual webs emerging from the primary drafting units.

Therefore, it is an object of this invention to provide a fiber blending system of the general type disclosed in said copending application, in which the primary or breaker drafting units in a row may include either or both the metallic roll type and the cushion roll type heretofore described, with all the units being driven by a common prime mover, and wherein driving connections are so arranged between the prime mover and the units that the speed of the delivery rolls of each primary drafting unit may be correlated relative to the speed of the delivery rolls of another unit or other units in the row to obtain substantially the same delivery rate of the webs emergi therefrom, and wherein the webs are individually tensioned and then superimposed and directed to a common processing unit by conveyor means common to all the primary drafting units and driven by said prime mover.

Another object is to provide a drafting system of the type last described wherein a pair of fluted calender rolls driven by the aforementioned prime mover is provided above the conveyor means and adjacent each primary drafting unit for individually advancing and crimping each respective web and maintaining the same under optimum tension in its course from the delivery rolls to the conveyor means.

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 perspective view of a preferred arrangement of drawing frames or drafting units for drafting and blending textile fibers according to the present invention;

FIGURE 2 is an enlarged fragmentary and elevation taken substantially along line 22 in FIGURE 1 and showing driving connections for rotating the primary calender rolls;

FIGURES 3 and 3A are, collectively, a somewhat schematic, enlarged, top plan view of the drafting and blending system shown in FIGURE 1 with the various drafting units thereof being uncovered for purposes of clairity;

FIGURE 4 is an enlarged front elevation of one of the drafting units showing how the corresponding web is directed to the conveyor means and superimposed upon webs from preceding drafting units, and being taken substantially along line 4-4 in FIGURE 3A;

FIGURE 4A is an enlarged detail of the mounting means for the fluted calender rolls 120, 121 of FIGURE 4;

FIGURE 5 is an enlarged vertical sectional view taken transversely of the drafting rolls of the unit shown in FIGURE 4 and substantially along line 55 in FIGURE 3A;

FIGURE 6 is an enlarged front elevation, partially in section, of the gearing shown in the right-hand portion of FIGURE 4; and

FIGURE 7 is a right-hand side elevation of the gearing shown in FIGURE 6 with corresponding support brackets being shown in phantom lines.

Referring more specifically to the drawings, the preferred embodiment of the fiber drafting and blending apparatus of this invention comprises a row of a plurality of individual side-by-side primary drafting units, there preferably being three or more such primary drafting units, and four of which are shown in FIGURE 1 and in combined FIGURES 3 and 3A, respectively, generally designated at I, II, III and IV. Fibers from the primary drafting units are directed to a common processing machine or secondary drafting unit V. Although all the drafting units I-V are directly interconnected and driven by a common prime mover embodied in an electric motor 10, each primary drafting unit may be self-contained to the extent that (a) each unit may draft a different type of fibrous material than the others, (b) each unit may impart a different amount of draft to the fibrous material than the others, and (c) the weight per unit length of the material being received by and delivered from each primary drafting unit may be different from that of the other primary drafting units. By directly interconnecting and driving all the primary drafting units from a common prime mover, uniform output speed of fibers from the primary units is obtained with respect to each other, even though periods of acceleration and deceleration of the drafting units may occur when starting and stopping the same.

As shown in FIGURES 1, 3 and 3A, a separate mass of textile fibers or textile material is introduced into each primary drafting unit I-IV in the form of a plurality of slivers S, such as card slivers, drawn from a suitable creel including supply cans C. Primary drafting units I-IV deliver the textile material, in the form of respective thin, veil-like, broad, flat, fibrous primary webs W1, W2, W3, W4 onto respective curled guide plates 11 which curve downwardly and beneath themselves to invert the respective webs and change their direction of movement by about 90 as they are deposited upon a supporting means in the form of a primary endless belt conveyor 12. The The upper run of conveyor 12. extends along the row of primary drafting units and below the level of the delivery rolls thereof to be later described, and toward the secondary drafting unit V. Thus, the webs are successively arranged into stacked or superimposed relationship to form, ultimately, a common multi-layered or composite web W5.

Endless belt conveyor 12 is driven, in a manner to be later described, to direct the webs W1-W4 along the row of primary drafting units and to direct the composite web W5 onto the upper run of a secondary belt conveyor 14 which extends upwardly and forwardly at an angle to direct the composite web W5 into secondary drafting unit V.

A calendering and crimping device 15 is provided above primary conveyor 12 and adjacent the discharge end of each curved plate 11 to aid in preserving the relationship of the fibers in each respective primary web W1-W4 while effectively pulling and advancing the respective primary web toward conveyor 12. Additionally, following the crimping and subsequent superimposing of the primary webs Wl-W4, and before the resultant composite web W5 enters the secondary drafting unit V, the composite web is compacted by means of a secondary calendering device 16. As shown, the secondary drafting unit V is arranged to blend and draft the composite web and deliver the same in the form of a web which may be taken up on a suitable roll, not shown, or which may be condensed into a blended sliver S (FIGURE 3A) and coiled into a can 20 for further processing.

Each drafting unit IV may comprise a plurality of sets of top and bottom drafting rolls, there being four sets of such rolls provided for each drafting unit in this instance, indicated at 31-34 and 31'34', respectively. Rolls 31-34 are generally known as No. 4, No. 3, No. 2 and No. 1 top rolls, respectively. The drafting rolls of all drafting units I-V may be arranged as shown in FIG- URES 4, 5 and 6, wherein portions of drafting unit IV are shown.

As stated earlier, however, it is desirable that the blending system is capable of accommodating either or both metallic roll type and cushion roll" type drafting units. Accordingly, the drafting units I-V may be of either or both types and, as shown in FIGURES 3 and 3A, for example, primary drafting units I, II and secondary unit V are each of the metallic roll type in which all the top rolls 31-34 are fluted and mesh with the respective bottom fluted rolls. On the other hand, primary units III, IV are shown as being of the cushion roll type in which all the top rolls may be of the cushion type or, as shown and is more generally the case, in which the delivery or No. 1 top roll 34 and the No. 2 top roll 33 are of the cushion type resting upon fluted bottom rolls; and the No. 3 and No. 4 top rolls 32, 31, respectively, are fluted metallic rolls meshing with the respective fluted bottom rolls 32', 31' (see FIGURE 5).

An explanation as to the reasons why each of these two types of drafting units has certain advantages over the other will now be given. A metallic roll type drafting unit is desirable for drafting and producing standard weight and heavy weight fibrous material of from 50 to 600 grains per yard or heavier whose fibers are of standard or greater coarseness (8 denier and more) because, even though the pressure applied to fluted top rolls may be as little as 16 pounds (which is about 5 percent of the pressure applied to cushion top rolls), the intermeshing flutes of metallic rolls, due to the bulk of the mass, grip such material very firmly so there is very little if any slippage of fibers between a pair of intermeshing fluted rolls. If such heavy weight and coarse denier fibrous material is being drafted through a cushion roll type drafting unit, the fibers in the core of the material will slip to a considerable extent relative to the outer fibers, even though a pressure of 200 to 320 pounds or more is being applied to the top cushion roll. It is apparent that the relatively lighter weighting required on fluted rolls reduces the wear metallic intermeshing rolls. The later types of fibrous ma- I terials are not grasped as firmly by a pair of metallic rolls because such rolls must not bottom against each other and, therefore, a small clearance is maintained between the ridges and valleys of the intermeshing flutes, which clearance is not filled by the small mass and thus permits some slippage of the latter types of fibrous materials between a pair of metallic intermeshing No. 1 or No. 2 rolls of a metallic roll drafting unit.

Metallic No. 3 and No. 4 top and bottom rolls are desirable in a cushion roll drafting unit because of the greater weight of the stock, the relatively small amount of draft being imparted thereto, and the relatively slow linear speed of the stock passing through these particular rolls as compared to the stock passing through the front drafting zone and between the delivery or No. 1 and the No. 2 drafting rolls. Thus, the earlierdescribed advantages of metallic roll drafting are applicable in the rear drafting zones of a cushion roll drafting unit.

All the bottom drafting rolls of the drafting units are driven by the prime mover 10 in a manner to be later described, and all the top drafting rolls are driven by contact with the textile material passing between the top and bottom drafting rolls. It is preferred that the fluted feed roll 31 of each primary drafting unit normally rests upon the slivers passing over the respective bottom feed roll 31' so that the feed rolls 31, 31 are in relatively deep intermeshing relationship upon a relatively thin place in the textile material passing therebetween, thus advancing such thin place at a relatively faster than normal speed. Conversely, upon a relatively thick place in the textile material passing between feed rolls 31, 31', the intermeshing relationship of the feed rolls 31, 31' is reduced so that the textile material is delivered to the succeeding intermediate drafting rolls 23, 32' at a relatively slower speed. Thus, the weight per unit of time of the material being received by the intermediate drafting rolls 32, 32 is substantially uniform, although the material being received by feed rolls 31, 31 may be of varying weight along its length. The feed rolls of the secondary drafting unit should not be capable of performing the evening action last described because they must take up all the webs W1-W4 in composite web W5 at a constant linear speed during normal operation of the system.

With the important exception that all the drafting units I-V are driven by a common prime mover, each primary drafting unit I-IV is arranged for independent operation to the extent that the fibers being drafted by each primary drafting unit may differ in one or more respects relative to the fibers being drafted by another or other primary drafting units. As to the differences in relative slipperiness of different kinds of fibers or slippage thereof relative to drafting rolls, tests have shown that, in a typical drafting unit utilizing a set of delivery rolls rotating at a given speed, the delivery speed of separately drafted different kinds of fibers varied from about 100 f.p.m. (feet per minute) to about 110 f.p.m. For example, a web formed only of Acrilan fibers (acrylic staple) issued from delivery rolls at about 100 f.p.m., a web formed only of Dacron fibers (polyester staple) issued from delivery rolls at about 104 f.p.m., and a web formed only of cotton fibers issued from delivery rolls at about 110 f.p.m. A blend of about 50 percent cotton fibers and about 50 percent synthetic fibers issued from corresponding delivery rolls at about 105 f.p.m. Further variation in delivery speed of the webs has also been experienced in changing from one denier and/ or staple length to another. It is axiomatic that such variations in delivery speeds cannot be tolerated if the required weight per unit length and distribution of fibers are to be achieved in the composite web W5 and the resultant drafted material made therefrom. Conversely, if it is assumed that the fibers being drafted through each primary drafting unit I-IV are of a different kind than the fibers being drafted through the other drafting units, it may be necessary to pull the webs W1-W4 from the respective units at slightly different speeds to allow for differences in cohesiveness of the fibers and stretchability of the different webs while providing for sufficient tension draft therein.

For the purposes of this disclosure, reference to various types of fibers, unless otherwise qualified, shall mean that the fibers in one or more masses differ from those fibers in another or other masses with regard to average staple length, relative slipperiness of adjacent fibers, and/ or slippage of the fibers relative to the corresponding drafting rolls, such that the roll spacing, the amount of draft effected in the drafting zone between adjacent sets of drafting rolls, and/or the speed of the delivery rolls 34, 34' required to effect a given delivery speed of the web at any one or more of the primary drafting units I-IV must differ with respect to another or others of the primary drafting units.

To provide for independent adjustment of the spacing of the drafting rolls of each drafting unit, the stepped bearings 36, 36' (Figure 6), in which opposite ends of each pair of top and bottom drafting rolls are journaled, are supported in substantially U-shaped bearing blocks 37, there being a separate bearing block 37 supporting each end of each pair of top and bottom drafting rolls. The bearing blocks 37 at each side of each drafting unit are relatively adjustable on corresponding roll stands 40, suitably secured to the frame 41 of the corresponding drafting unit. As shown in FIGURES 5 and 6, each roll stand 40 may be provided with a longitudinal slot 43 in its upper bridging portion through which a screw 44 for each bearing block 37 extends for securing the bearing blocks in the desired adjusted positions in accordance with the staple length of the fibers in the particular mass being drafted by the particulardrafting unit.

As heretofore stated, all the drafting units I-V are driven by prime mover 10.

As shown, a common jack shaft 50 extends along the row of primary drafting units I-IV and is drivingly connected to the front drafting rolls of each primary drafting unit by an individual transmission means or gear train including a drive gear 51 fixed on shaft 50 and meshing with one of a pair of change gears 53 (FIGURE 6). The other of the change gears 53 engages a gear 54 fixed on one reduced end of the corresponding bottom delivery drafting roll 34'. It is important to note that the change gears 53 provide means for adjustably controlling the speed of each pair of delivery rolls 34, 34' independently of the other pairs of delivery rolls, as well as adjustably controlling the speed of all the rolls of each respective primary drafting unit, even though all the primary drafting units are driven by jack shaft 50.

The change gears 53 associated with each primary drafting unit are fixedly interconnected in axial relationship and are mounted on a stub shaft 58 adjustably secured to a pivoted bracket 59 whose lower portion is pivotally supported on jack shaft 50. Each pivoted bracket 59 is provided with an arcuate slot 60 therein (FIGURE 7) penetrated by an adjustment screw 61 for adjustably securing the same to a standard 62. Each standard 62 is fixed upon the frame 41 of the corresponding primary drafting unit. Jack shaft 50 is journaled in standards 62 and may extend through the roll stands 40 of primary drafting units I-IV so that it may be positioned beneath and adjacent bottom delivery rolls 34', as is preferred. If so desired, jack shaft 50 may be manufactured in short sections with suitable couplings 64 (FIGURES 3 and 3A) interconnecting adjacent sections thereof at the junctures of adjacent primary drafting units.

The end of jack shaft 50 adjacent secondary drafting unit V is connected to the output side of a gear box 66 whose input side has a sprocket wheel 67 fixed thereon engaged by an endless sprocket chain 70. Sprocket chain 70 is also mounted on a sprocket wheel 71 fixed on a shaft 72 connected by a train of gears 73 to the drafting rolls of secondary drafting unit V. The drafting rolls of secondary drafting unit V are interconnected, in a conventional manner, by the usual draft gearing and the front bottom drafting roll 34 of secondary drafting unit V is connected to electric motor or prime mover 10, preferably by means of an electromagnetic clutch 76 which may be energized and deenergized in a well-known manner for starting and stopping secondary drafting unit V and thus for starting and stopping the entire drafting and blending system of the present invention.

The means for varying the amount of draft and transmitting rotation to the intermediate and back drafting rolls of each primary drafting unit I-IV from the respective front or bottom delivery roll 34 may be similar to that disclosed in my said copending application. Accordingly, the means for transmitting rotation from the bottom delivery roll 34 of each primary drafting unit to the intermediate and back drafting rolls will not be described in detail, it being deemed sufficient to state that each gear 54 is connected to one of the intermediate drafting rolls through a gear train including change gears 80, and the other end of the latter intermediate bottom drafting roll is connected by a gear train 81 to the other intermediate bottom drafting roll and to the bottom feed roll 31' of the corresponding drafting unit. Change gears 80 are secured in fixed axial relationship and mounted on a stub shaft 83 adjustable in a slotted bracket 84 (FIG- URE 7) to enable the use of change gears 80 of different sizes for changing the relative speeds of the intermediate drafting rolls 32, 32 and 33, 33' of each primary drafting unit and thereby to change the amount of draft effected by the corresponding drafting unit without the necessity of changing the speed of delivery rolls 34, 34'.

Any suitable means may be employed for applying yieldable downward pressure to each end of each top drafting roll 31-34, such as is shown in United States Patents Nos. 2,412,357 and 3,143,772, for example. Such pressure-applying means may include a separate springloaded plunger 90 bearing against each bearing 36. The spring-loaded plungers at each side of each drafting unit may be carried by supports 91 overlying the corresponding bearings 36.

The enlarged portions of those bearings 36 (FIGURE which support any intermediate and front top rolls 32, 33, 34 which are of the metallic fluted type (as is the case with respect to primary units I, II) bear against the respective bearings 36 therebeneath to ensure a predetermined depth of intermeshing relationship of the respective pairs of rolls, and thereby to prevent bottoming of the fluted rolls and to ensure that the stock leaves each such pair of fluted rolls at a constant linear speed relative to the peripheral speed of the corresponding rolls. This is also true with respect to the feed rolls 31, 31' of the secondary drafting unit V.

The endless belt conveyor 12, upon which webs W1- W4- are successively superimposed, and the secondary or ramp belt conveyor 14 which conveys the composite web W5 from conveyor 12 to secondary drafting unit V, are mounted on respective pairs of pulleys 100, 101; 102, 103 suitably rotatably supported by the frames of adjacent drafting units. Adjacent pulleys 101, 102 of belt conveyors 12, 14 may be drivingly interconnected by a pair of sprocket wheels 105, 106 and an interconnecting endless sprocket chain 107 at one end thereof (FIGURE 3A). The other end of conveyor pulley 101 is connected to one of the output sides of gear box 66 by means of a pair of sprocket wheels 110, 111 and an interconnecting endless sprocket chain 112, thus operatively connecting the conveyors 12, '14 to prime mover 10.

In order to maintain the upper runs of belt conveyors 12, 14 in substantially straight condition during operation thereof, suitable support plates or platforms 115, 116 may be provided therefor. Platform may be supported by cantilever arms 117 secured to and projecting outwardly from the frames of adjacent primary drafting unils. Platform 116 may be similarly supported by the frame of secondary drafting unit V.

The primary calendering devices 15 (see FIGURES and 4A) are provided to ensure the desired degree of adjustment of the rate of travel of the primary webs W1- W4, under the desired tension, from the respective primary drafting units to the belt conveyor 12, especially when cushion-type top delivery drafting rolls are used. In this connection, space limitations and economy in manufacture dictate that the gears 5254 (FIGURE 6) should be relatively small. The range of change gears, such as gears 53, which may be used does not always permit the fine adjustment of tension draft needed for best results.

Therefore, as best shown in FIGURES 4 and 4A, each primary calendering device comprises a pair of top and bottom fluted intermeshing calendering rolls 120, 121 which may be of the same type as illustrated feed rolls 31, 31' of each drafting unit. As will be later explained, it is important that the depth of intermeshing relationship of each pair of primary calender rolls 129, 121 is accurately controlled. Therefore, reduced opposite ends of rolls 120, 121 are rotatably mounted in respective top and bottom bearings 120a, 121a (FIGURE 4A) mounted in substantially U-shaped bearing stands 123. The bearings 120a bear against the bearings 1210. Various diameters of bearings 120a may be employed to permit changing the depth of mesh of each top calender roll 120 with the respective bottom roll 121 to impart the desired rate of travel to each web Wl-W4 from the delivery rolls 34, 34' to conveyor '12. Bearings 120a may be engaged by suitable spring weighting devices or spring pressure devices 125 mounted in the respective bearing stands 123 so as to maintain the top calender rolls 120 in pressure engagement with the primary fibrous webs passing between respective pairs of calender rolls 120, 121.

To aid in effectively directing each web onto belt conveyor 12 or onto another or other webs on the belt conveyor 12, as the case may be, the discharge end of each curved plate 11 terminates closely adjacent the nip of the respective pair of primary calender rolls 120, 121, and, additionally, the calender rolls 120, 121 are arranged in angular positions; i.e., an imaginary line extending through and perpendicular to the axes of the calender rolls 120, 121 extends at an acute angle with respect to the forward direction of movement of the upper run of belt conveyor 12. Bearing stands 123 may be suitably secured to corresponding cantilever arms 117 heretofore described (FIG- URES 3, 3A, 4 and 5).

The bottom calender rolls 121 of the primary calendering devices 15 are drivingly connected to a calender drive shaft by suitable gearing, not shown, in respective gear boxes 131 suitably secured to the respective cantilever arms 117. Calender drive shaft 130 is common to all the primary calendering units 15, is rotatably supported in gear boxes 131, and is driven by suitable driving connections with jack shaft 50, such as are shown in FIGURE 2. Accordingly, the end of shaft 130 adjacent the first primary drafting unit I has a gear 133 fixed thereon which meshes with an idler gear 134 suitably supported by the frame of drafting unit I and fixed in a axial relation to a pulley 135. Pulley 135 is engaged by an endless belt 136 which also engages a pulley 137 fixed on the corresponding end of jack shaft 50. It is thus seen that prime mover 10 is drivingly connected to the bottom rolls 121 of the primary calcndering devices 15.

Prime mover 10 is also drivingly connected to a pair of smooth-faced calender rolls 140 of secondary calendering device 16 by means of a pair of sprocket wheels 141, 142 and an interconnecting endless sprocket chain 143. Sprocket wheel 141 is fixed on one reduced end of the bottommost of the smooth-faced calender rolls 140, and sprocket wheel 142 is arranged in fixed axial relation to sprocket wheel 111. The calender rolls 140 of secondary calendering device 16 may be mounted in the same manner as rolls 120, 121 of the primary calendering devices 15 and, therefore, a further description of the calendering device 16 is deemed unnecessary.

Generally, any drafted fiber web is thicker longitudinally of its central portion than it is at its outer edges. This results in the web gradually increasing in width when it is being pulled from delivery rolls 34, 34 between the primary calender rolls 120, 121 (FIGURE 4) and while the webs are being advanced by the conveyor means 12, 14. I have discovered that, owing to the fact that synthetic fibers have slicker or smoother and more slippery surfaces than natural fibers, such as cotton fibers, synthetic fiber webs spread laterally when being pulled, to a greater extent than cotton webs. Therefore, when blending synthetic and cotton fibers according to this invention, the slivers S may be so arranged upon entering the respective primary drafting units I-1V that any synthetic fiber web or webs emerging therefrom are compensatively narrower than any cotton web or webs emerging therefrom so that, by the time that the composite web W formed therefrom reaches the secondary drafting unit V, the synthetic fiber web or webs will have increased in width to a greater extent that the natural fiber web or webs so that all the webs of the composite web W5 will be of substantially the same width, thus further contributing to uniformity of the blend.

In accordance with this invention, it can be appreciated that each primary drafting unit (1) is capable of drafting textile fibers of a different type (different kind and/or average staple length) than that of the fibers being drafted by the other primary drafting units, (2) is capable of applying a different amount of draft to corresponding fibers than that applied by the other primary drafting units, and (3) may deliver the corresponding primary web therefrom at substantially the same speed as that at which the primary webs are delivered from the other primary drafting units and in accordance with the speed at which the webs are to be drawn into the secondary unit V.

Even though the bottom delivery rolls 34' of all the primary drafting units I-IV are driven by the jack shaft 50 and may be of the same diameter, and the fibers being drafted by any one of the primary units may slip relative to corresponding drafting rolls to a greater or lesser degree than the fibers being drafted by another or others of the primary units, it should be noted that the change gears 53 provide means for adjusting the speed of each pair of delivery rolls so the delivery speed of all the primary webs may be substantially the same, thus providing a basis for determining the rate of travel of each primary web in its course to belt conveyor 12. Such changes in the speed of the delivery rolls are automatically reflected in the speed of all the rolls of the respective primary drafting units without changing change gears 80.

The primary calender rolls 120, 121 serve the function of imparting added crimp to each primary web when fluted delivery rolls are used or impart initial crimp when composition top delivery rolls are used at the drafting units LIV. More importantly, the primary calender rolls 120, 121 provide means for facilitating proper tension draft for each one of the different types of webs emerging from the primary drafting units, while providing for the proper rate of feed of each one of the webs onto primary conveyor 12. The latter function of fluted calender rolls 120, 121 may be appreciated by comparison of the action of the fluted calender rolls upon two different types of webs; namely, a synthetic web and a cotton web, both of the same weight and emerging at about the same linear speed from delivery rolls 34, 34 of different primary drafting units.

By proper selection of gears 133, 134 (FIGURE 2) optimum surface speed of all calender rolls (about equal to that of delivery rolls 34, 34') may be obtained. The tension draft in each primary web must be held to a minimum, but must be sufficient to ensure proper conveyance of each web to the conveyor 12. If the tension draft is too high, the primary web may be subjected to undesirable false draft, or it may be pulled apart, or holes may be formed therein, as it is being pulled around the respective curved guide plate 11. However, due to differences in cohesiveness of synthetic and cotton fibers, a synthetic fiber web may tend to sag more than a cotton fiber web. Consequently, with the two webs emerging from delivery rolls 34, 34' at about the same linear speed, the rolls 120, 121 for the synthetic web would have to be in deeper intermeshing relationship than the fluted calender rolls for the cotton web so as to advance the synthetic web faster than the cotton web.

Although this results in a greater length of the synthetic web emerging from corresponding fluted calender rolls 120, 121 per unit of time than that of the cotton web, the crimping effect of the fluted calender rolls causes both types of webs to emerge from the respective pairs of calender rolls in somewhat corrugated or undulated form, and the linear speed of the upper reach of conveyor 12 is such as to impart a small amount of tension to the webs as they are deposited and/or superimposed thereon. Elasticity is imparted to the primary webs by virtue of the crimp imparted thereto by the fluted calender rolls 120, 121.

Thus, the pull of the conveyor acting on the corrugated synthetic and cotton webs removes only a relatively small amount of the undulations or crimp from the faster moving synthetic web as compared to the amount removed from the slower moving cotton web to avoid excessive accumulation or pile-up of the faster moving web on conveyor 12 and to ensure proper successive superimposing or stacking of the different types of webs on conveyor 12.

In the event of the synthetic web being delivered to conveyor 12 so much faster than the cotton web that the weight per unit length of the synthetic web layer of the composite web W5 is too great with respect to the cotton web layer, the delivery speed of the synthetic web at corresponding delivery rolls 34, 34' may be reduced by use of appropriate gears 53. or preferablv bv increasing the draft of the corresponding rimary drafting unit, so the weight of the synthetic web approaching corresponding calender rolls 120, 121 will have been reduced compensatively.

Another important feature of the instant invention is that the composite web W5 formed by superimposing the plurality of primary webs =W1-W4 passes directly from the primary units into the secondary drafting unit V which drafts and reduces the composite web to the final desired weight per unit length, either in the form of a web which may be rolled up or which is condensed into a final sliver and coiled into a can for further processing. The superimposing of primary webs, wherein one one or more of the webs may be formed of a different type of fibers than the other webs, eflects a uniform distribution of the fibers of each web throughout the width of the composite web and the drafting of the composite web through the secondary drafting unit blends and intersperses the various types of fibers with each other in a homogenous manner to produce a thorough blending of the various fibers and a highly uniform Weight of the fibrous material issuing from the secondary drafting unit.

As an example of one type of blend of fibers which may be obtained utilizing the system of the present invention, it may be assumed that a secondary sliver S weighing 60 grains per yard is to be obtained having 20% 20% combed cotton fibers of about one one-eighth inch combed cotton fibers of about one and one-eighth inch average staple length, 30% Orlon fibers of about one and nine-sixteenths inches average staple length, and 40% Acrilan fibers having three inches average staple length therein. It may be assumed further that the slivers S fed into the primary units each weigh 60 grains per yard, with all the slivers S except the combed cotton slivers being card slivers. Although there are various ways in which the various types of slivers may be arranged in the primary drafting units I-IV to obtain the desired blended sliver S therefrom, one example as to how the slivers may be arranged will now be given.

In setting up the apparatus, thirteen ends of card slivers of Acrilan fibers having three inches average staple length may be directed from separate cans C into metallic roll primary drafting unit I; ten ends of Orlon fibers having an average staple length of two inches may be directed from separate cans into metallic roll primary drafting unit II; five ends of Dacron fibers having two inches average staple length may be directed into cushion roll primary drafting unit III; and eight ends of combed cotton fibers having one and one-eighth inches average staple length may be directed into cushion roll primary drafting unit IV. The total draft imparted to the fibers at the primary drafting units I-V would be 4.07; 4.16; 6.25 and 5, respectively. Thus, the primary webs Wl-W4 is suing from the drafting units I-IV would weigh about 192, 144, 48 and 96 grains per yard, respectively, and the composite web W5 formed thereform thus would weigh about 480 grains per yard. The 480 grain-per yard composite web W5 would then be subjected to a draft of 8 as it is passed through secondary drafting unit V to form the blended sliver S weighing 60 grains per yard.

It will be noted that primary units I, II of this example are of the metallic roll type, as is desirable in producing the heavier webs of synthetic fibers. 0n the other hand, primary units II, III of this example are of the cushion roll type, as is desirable in producing the very light (48 grains per yard) Dacron web and the highly parallelized combed cotton web.

It can be appreciated that the delivery speed of and amount of draft imparted to the fibers by the secondary drafting unit V are substantially greater than that of each primary drafting unit. Also, since the composite web is quite heavy and is formed largely from synthetic fibers, the secondary unit preferably is of the metallic roll type.

Heretofore, and prior to the development of the system disclosed in my said copending application, the only method I am aware of by which different types of slivers could be blended in accurate proportions to obtain blends having a wide variance in the components thereof, such as that described, has been to produce slivers of different weights per unit length and then draft several such different types of slivers through a common drafting unit. Even then, many proportions of different types of fibers could not be obtained. Obviously, variation in the size of slivers has undesirably reduced the production capabilities of one or more sliver-producing machines in the mill, such as carding machines. In producing a 60 grainper-yard blended sliver of the type mentioned in the foregoing example, but practicing the prior art method, as many as four or more different sizes of slivers varying from about 44 to 60 grains per yard may be required. Also, the various types of fibers would not be distributed, intermixed or drafted with the uniformity or efficiency obtainable according to the instant method where the blending is by thin webs instead of slivers.

It is important to note that the primary webs Wl-W4 are compacted and crimped individually by the fluted calender rolls 120, 121 associated with the primary drafting units to lend tensile strength thereto to assist in preventing rupture of the thin primary webs as they are superimposed, and to effect an efficient transition of the webs to the conveyor means. A further compacting of the webs occurs at the secondary calendering device 16 which not only lends tensile strength to composite web W5, but also intermixes the fibers of adjacent superimposed webs in the composite web W5, thus further assisting in the homogenous distribution of the various types of fibers throughout the blend.

Although the fibrous material or stock is shown in the accompanying drawings being directed to the primary drafting units I-IV in the form of slivers being drawn from individual cans, it is contemplated that the incoming stock may be taken from sliver lap rolls or ribbon lap rolls. However, since it is necessary that all the fibers are withdrawn from any one sliver lap roll or ribbon lap roll at a given speed, the enlarged inner portions of those bearings 36 (FIGURE 6) associated with the feed rolls 31, 31' of any primaly drafting units receiving stock from a sliver lap roll or ribbon lap roll would have to be of such diameter that they would remain in engagement with the enlarged portions of the corresponding bottom feed roll bearings 36' at all times during operation of a corresponding primary drafting unit or units, since a variation in the rate of feed of various portions of the webs coming from the ribbon lap rolls or sliver lap rolls to a particular drawing frame could not be tolerated.

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 only and not for purpose of limitation, the scope of the invention being defined in the claims.

Iclaim:

1. A drafting system for blending a plurality of masses of textile staple fibers comprising a row of primary drafting units arranged to produce simultaneously from respective masses respective fibrous webs; each drafting unit comprising a series of drafting rolls including a front pair of drafting rolls; a common processing unit adjacent said row of drafting units; means for arranging the webs emerging from said drafting units in superimposed relationship and for directing the superimposed webs to said common processing unit and comprising endless conveyor means extending along said row of drafting units to said common processing unit and respective fluted calender roll means operatively associated with each drafting unit and cooperating with said conveyor means for directing the webs onto the conveyor means in superimposed rela tionship; and drive means connected to said drafting units, said conveyor means, said calender roll means and said common processing unit, said drive means including transmission means-connected to each drafting unit and controlling the speed of rotation of the front drafting rolls of the drafting units independently of each other and independently of the speed of said common processing unit.

2. A structure according to claim 1 wherein said common processing unit is a secondary drafting unit, and a pair of driven calender rolls are positioned adjacent said secondary drafting unit for compacting all of said superimposed webs before their entry into said secondary drafting unit.

3. A structure according to claim 1 in which said means for arranging the webs in superimposed relationship further comprises a curved slide member situated to support and guide the web from each primary drafting unit downwardly to a point closely spaced above said conveyor means.

4. A drafting system for blending a plurality of masses of textile staple fibers comprising a row of primary drafting units arranged to produce simultaneously from respeE- tive masses respective fibrous webs; each drafting unit comprising a series of drafting rolls including a front pair of drafting rolls; a common processing unit adjacent 13 said row of drafting units, means for arranging the webs emerging from said drafting units in superimposed relationship and for directing the superimposed webs to said common processing unit; a common prime mover drivingly connected to all said drafting units and to said common processing unit for driving the same; transmission means interposed in driving connections between said prime mover and each drafting unit for controlling the speed of rotation of the front drafting rolls of the drafting units independently of each other and independently of the speed of said common processing unit; and said means for arranging the webs comprising an endless belt conveyor extending along said row of drafting units, a pair of fluted intermeshing calender rolls arranged to impart crimp to each respective web and maintain tension draft in each respective web in its course from each drafting unit to said belt conveyor, and means drivingly connecting said prime mover to said calender rolls and said belt conveyor such that the linear speed of the belt conveyor causes the belt conveyor to pull and partially remove the crimp from the webs in their course from the calender rolls to said belt conveyor.

References Cited UNITED STATES PATENTS 630,813 8/ 1899 Meats 19-243 1,351,678 8/1920 Nuckols 19288 XR 1,994,174 3/1935 Fossel 19258 2,878,527 3/1959 Whitehurst 19159 3,063,101 11/1962 Andreani 19-243 FOREIGN PATENTS 498,148 1/ 1939 Great Britain.

OTHER REFERENCES Saco-Lowell bulletin, 1932, September-October, p. 6.

20 DORSEY NEWTON, Primary Examiner zgxgfi UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 595 D t d July 29, 1969 Inventor) Joe R. Whitehurst It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 3, Line '74, after the numeral "121' omit the word "The". Column 5, Line 34, after "fluted" insert top--; Column 5,

Line 44, "23, 32'" should be --32, 32'-. Column 10, Line 63,

omit the first occurrence of "one". Column 11, Line 2, omit "20%"; Column 11, Lines 2 and 3, after the first occurrence of "one" omit "one-eighth inch combed cotton fibers of about one"; Column 11, Line 4, after "length" insert --10% Dacron fibers of about two inches average staple 1ength-; Column 11, Line 27, "I-V" should be IV-; Column 11, Line 31, "thereform should be --therefrom Column 12, Line 31, "purpose" should be --purposes.

SIGNED 'AND SEALED APH28B70 (SEAL) .Attest:

Attesting Officer WILLIAM E. Commissioner: 0

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