US 2693844 A
Description (OCR text may contain errors)
Nov. 9, 1954 E. BAY 2,693,844
APPARATUS FOR REINFORCING SHEET MATERIAL Filed Dec. 30, 1950 2 Shee ts-Sheet 1 TEl INVENTORZ Ernesf B 0 v 1 [wu ATTO NEYS' NOV. 9, 1954 BAY 2,693,844
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United States Patent APPARATUS FOR REINFORCING SHEET MATERIAL Ernest Bay, Saylesville, R. I., assiguor to Owens-Coming Fiberglas Corporation, a corporation of Delaware Application December 30, 1950, Serial No. 203,742
3 Claims. (Cl. 154-176) This application relates to the material, for example, heavy paper and, more particularly, to that phase of the art having to do with the deposition of reinforcing fibers on the sheets to be reinforced.
Heavy reinforced papers usually are laminated and may sheets of paper between which art of reinforcing sheet consist in two or more a suitable bonding material such as asphalt may be spread to bond the sheets together and maintain in place such reinforcing fibers as also may be inserted between the laminations of paper. Machines and methods for inserting regular pattern reinforcing fibers as, for example, woven fabrics such as open mesh fabrics in laminated papers have been developed, but the cost of inserting regular pattern fabrics is substantially due to the necessity for first arranging the fibers and then weaving or otherwise orientating the strands in, the regular patterns. Other machines are known for feeding parallel strands or fibers which extend longitudinally of the sheet material being reinforced and for also laying transverse strands or fibers between the sheets. Such machines are costly and require careful control particularly where the widths of the papers being reinforced may vary from time to time. Other machines have been built for reinforcing sheet materials by the random deposition of fibrous materials between their laminations and it is to this latter class of machines that this invention is directed.
The structure shown in Patent No. 2,392,882 to Roberts is an example of a prior art structure which may be employed in carrying out the random deposition of fibers between laminated sheets. The invention set forth herein consists in an apparatus embodying improvements 'over the illustrative apparatus disclosed in Patent No; 2,392,882 and provides an improvement in the method disclosed therein.
An apparatus embodying the instant invention isshown in connection with a conventional paper laminating machine in the drawings in which:
Fig. 1 is a somewhat diagrammatic view, in elevation, of a machine embodying the apparatus portion of the present invention, shown in cooperation with a paper laminating machine and illustrating apparatus on which the method of the invention satisfactorily may be carried out.
Fig. 2 is a plan view of portions of apparatus shown in Fig. l and is broken to indicate the fact that a machine embodying the invention may be adapted for the reinforcement of papers of widths greater than that shown.
Fig. 3 is a fragmentary enlarged view in elevation taken substantially from the position indicated by the line 3--3 of Fig. 1 and illustrating particulars of struc ture embodying the invention.
Fig. 4 is a fragmentary detailed view partly in elevation and partly in section taken substantially on the line 44 of Fig. 3. v
Fig. 5 is a detailed, greatly enlarged, vertical sectional view of an air jet nozzle with which a machine embodying the invention is equipped.
Fig. 6 is a much further enlarged, fragmentary, sectional view of a portion of a sheet of reinforced laminated paper fabricated on the apparatus disclosed and through the practice of the method constituting the instant invention.
Fig. 7 is a fragmentary plan view of a portion of a sheet of laminated paper such as that shown in Fig. 6 and illustrating the random deposition of fibers resulting from the operation of the apparatus disclosed in the preceding figures and through the practice of the method herein disclosed.
In feeding continuous strands of fibers when each strand may be monofilament, or may consist in yarns, or twists, slivers or rovings, the problem of maintaining a supply of the individual strands being fed and of uniformly withdrawing the strands from the supply so that they can be freely fed at a high rate of speed, is one which has required considerable attention. Modern paper laminating machines operate at high rates of speed as, for example, in the order of to 200 lineal feet per minute and it is necessary, of course, to supply the reinforcing fibers to the paper laminating machine at a lineal speed sufficient with respct to that of the paper laminating machine, so that the deposition of the fibers thereon may follow the desired, at least general, pattern.
Where the reinforcing fibers are interlaid in a regular pattern as, for example, by the feeding of a fabric made up of longitudinally and transversely extending interwoven or overlaid fibers, the reinforcing mesh of fabric need be fed only at the same lineal rate as that of the webs of paper being laminated. Where, however, the reinforcing fibers are deposited in a more or less random manner and thus must extend both longitudinally and generally transversely of the webs of paper being reinforced, it is necessary that the lineal feeding speed of the fibers shall be greatly in excess of the lineal speed of the paper web on which they are deposited so that they can assume on such web a general random pattern such as may be desired.
Preferably the random pattern of continuous fibers which is fed between the sheets being reinforced should be deposited therebetween without the necessity for devices to control the direction of each of the fibers, i. e., mechanisms for depositing the fibers should not lnclude devices for mechanically moving the fibers laterally of the paper web to insure a random pattern, both because of the expense of constructing and maintaining such mechanisms and in order to eliminate the physical manipulation of such fibers which may break the fibrous strands.
The supplies of individual fibers used usually ex1st in the form of either random masses of strands or spools of strands, preferably the latter, inasmuch as no mechanism is then necessary for arranging the strands into condition to be fed longitudinally. If individual spools of strands are used as supply sources, means must be provided for feeding the fibers off the spools at a substantially uniform rate of speed with a sufficiently positive force to insure the removal of the strands from the spools and to maintain the necessary high rate of feed.
In an apparatus embodying the instant inventlon or designed for the practice of the method lncluded 1n the instant invention, spools 10 of strands or yarns are mounted upon spindles 11 which extend horizontally from a frame or bracket 12 and each spool 10 has associated with it a feeding eye 13 that is mounted upon an arm 14 also supported from the bracket 12. Each of the feeding eyes 13 is in line with the axis of the assoc ated spindle 11 on which the associated spool 10 1s mounted.
For the purpose of uniformly withdrawing a strand 15 from its spool 10, the apparatus is provided w th strand feeding means each of which consists 1n associated elements now to be described. The number of strand supply g spools 10 and of feeding means will, of course, depend upon the maximum width of the paper or other sheet material to be reinforced. A framework generally mdlcated at 16 is erected from the base of the apparatus and serves as a general frame for the mounting of various bearings and other elements which support the feeding means. In the apparatus illustrated in the drawings, there is provided an individual driving wheel 17 (see also Fig. 3) for each of the feeding means in the machine. Each wheel 17 is keyed to a shaft 18 which is, in turn, mounted in bearing blocks 19 on the frame 16. Inasmuch as the individual wheels 17 are all keyed to the common shaft 18, they may, if desired, be replaced by a single cylindrical driving member which would serve to drive all the feeding mechanisms. The shaft 18 is rotated at a h1gh rate of speed by means of a belt 20 engaged Wl'th a driving pulley 21 pinned or otherwise secured on the other end of the shaft 18, the belt also being engaged with the output of a speed change mechanism 22 which is motivated by a motor 23. Through the medium of the speed change mechanism 22, the speed of rotation of the driving wheels 17 may be varied ultimately to vary the linear speed of the strands 15 in accordance with the linear speed of operation of the paper laminating machine with which the apparatus is used.
Each of the driving wheels 17 is provided with a friction tire 24 (see Fig. 4) which is peripherally engaged with a lower feeding roller 25. The roller 25 for each of the feeding means for one of the strands 15 is rotatably mounted on the forward end of an individual rocker arm 26 that is supported on a transverse shaft 27 mounted in blocks 28 on the frame 16. Each of the rocker arms 26 is independently mounted on the shaft 27 so that its roller 25 can be lifted or lowered independently of the other rollers 25 associated with other strands 15. It will be noted in Fig. 4 that the axis of rotation of the lower feeding roller 25 does not lie in the same vertical plane as the axis of rotation of its associated driving wheel 17 but is located slightly in advance (with respect to the direction of movement of the engaged surfaces of the roller and wheel) of the vertical plane through the axis of the driving wheel 17 (to the right in Fig. 4).
The lower feeding roller 25 is, in turn, engaged with the periphery of an upper feeding roller 25 located above the roller 25 and similarly rotatably journalied in the end of its own individual rocker arm 30 which is mounted upon a second transverse shaft 31 supported on the front end of a frame arm 32. The location of the axis of rotation of the second feeding roller 29 with respect to the axis of rotation of the lower feeding roller 25 is similar to that obtaining between the axes of the lower feeding roller 25 and the driving wheel 17, i. e., it lies slightly in advance of the vertical plane of the lower roller, again with respect to the direction of movement of the adjacent surfaces of the rollers, to insure good frictional contact between the surfaces of the rollers 25 and 29.
Although in the embodiment of the invention shown in the drawings, the driving wheels are shown as having tires 24, the feeding rollers may also have friction tires. It may be desirable, indeed, under some conditions and depending possibly on the nature of the strands being fed, for the driving wheel 17 to have a smooth periphery such as a steel tire or rim and for the feeding rollers 25 and 29 to both be provided with friction tires, for example, tires made of rubber or other similar material.
The offset relationship between the axes of the three associated rotatable elements, i. e., the individual driving wheels 17 (or their cylindrical counterpart) and the two feeding rollers 25 and 29 eliminates the bumping or irregularity of contact that frequently occurs when wheels are arranged in peripheral driving engagement with their axes and the point of peripheral engagement all lying in the same vertical plane. By moving the axis of the driven wheel to one side, so that the surfaces of the wheels contact ahead of the vertical plane of the lower driving wheel, a smooth continuous engagement and drive results.
A strand 15 which is associated with the feeding appa ratus comprising the wheel 17 and rollers 25 and 29, is fed between the peripheries of the rollers 25 and 29 and frictionally gripped therebetween so that, as the rollers rotate, the strand is pulled through its feeding eye 13 and off its spool 10 at a rate of speed equal to the lineal speed of the feeding rollers 25 and 29 at their point of engagement. Even though the surfaces of the rollers 25 and 29 may be held together solely by the weight of the roller 29 on its rocker arm 30 a sutficiently positive feed is provided to avoid the development of lashback, kinks or snarls which might result in snapping the strand and to insure the feeding of the strand at a rate sufficient to result in the desired random pattern of the strand on the web of paper being reinforced. The points of engagement between the several lower feeding rollers 25 and upper feeding roller 29 preferably should lie on approximately the same horizontal plane as the center lines of the feeding eyelets 13 and spools 10 forming the supply of strands 15 which reduces friction and helps prevent snarls and entanglements of the strands with the mechanism.
For each of the feeding apparatuses comprising the driving wheels and two feeding rollers for the feeding of a strand 15, an apparatus embodying the invention also is provided with a secondary air feeding means consisting in a nozzle 33, each of which is mounted on a bracket 34 also supported on the frame arm 32 and depending therefrom. Each of the nozzles 33 (see also Fig. 5) is generally cylindrical in shape and consists of two telescoped, generally cup-shaped members 35 and 36 which have coaxial openings 37 and 38 respectively. The telescoping fianges of the members 35 and 36 are so shaped as to provide an interior annular space 39 communicating with a threaded inlet 49 into which is secured the end of an air supply hose 41.. The annular space 39 communicates with the coaxial openings 37and 38 in the members 35 and 36 to result in a jet of air (indicated by the arrows in Fig. 5) being emitted from the exit side of the axial opening 38. The entrance end of the axial opening 37 in the member 36 may be cone shaped as shown in Fig. 5 to allow the admission of substantial volumes of air and to facilitate the insertion of a strand 15 into the opening 37 and through the opening 33. Similarly, as shown in Fig. 5, the innermost end of the opening 37 may be of a diameter slightly less than thatof theopening 38 and the two openings may be slightly flared to facilitate both theinsertion of the strand 15 and to result in the creation of an ejector action tending to pull air through the orifice in addition to the blast of air forced therethrough from the pressure line 41.
The blast of air which is emitted from the orifice 38 generally surrounds the strand 15 which passes therethrough and maintains it out of engagement with the walls of the coaxial openings 37 and 38 forming the orifice thus eliminating frictional wear on the strands and subjecting each strand to a longitudinal flow of air which causes it to flutter, as it were, in much the same manner as a flag or pennant flutters in a high wind. The effect of the fluttering action of each strand in the blast of air through which it passes may be modified and/or amplified by the characteristics of the strands being used. If a neutral or balanced yarn or a strand of parallel straight fibers grouped together is employed, the resulting pattern is less involved. Such strands react to loss of tension and the blast of air taking place at the nozzle 33 to produce random swirled patterns of more or less wave shape rather than looped shape.
Preferably, at least when the reinforcing strands are glass, a so-called wild yarn is employed resulting in a much more involved pattern. A wild yarn is one in which a group of individual fibers are all twisted together and not neutralized by wrapping with other twisted fibers or strands. When tension on such a wild yarn is reduced or eliminated, as is the case after the strand leaves the nozzle 33, the stored energy in the twisted fibers causes the strand to coil on itself. This action combines with the flutter to produce irregular convolutions or loops in the strand.
The type of strand employed may depend on the degree of convolution desired, the material from which the strand is made or the per cent of reinforcement to sheet material desired.
As can be seen most clearly in Figs. 1 and 2, the nozzles 33 are spaced a considerable distance away from the converging paths of two webs of paper 42 and 43 which are being laminated together by pressure rollers 44 and 45 of a paper laminating machine generally indicated at 46. The horizontal level of the nozzles 33 and thus of the strand feeding means and strand supplies should be somewhat higher than that of the engagement plane of the pressure rollers 44 and 45 to compensate for the action of gravity which causes the strands to drop slightly while travelling across the space between the nozzles 33 and the rollers 44 and 45.
During the travel of the strands across the space bevolutions overlapping each other as can be generally seen in Fig. 2 and more particularly seen in Figs. 6 and 7 in which the individual strands and an illustrative relationship between them is shown.
A paper laminating machine generally indicated at 46 may comprise, among other parts, a framework 47 on which are mounted the rollers 44 and 45 and which is provided with sets of V blocks 48 and 49 for the reception of rolls of paper 50 and 51 respectively. The web of paper 42 which is fed off the supply roll 56 is led over an idler roller 52 mounted at the top of the frame 47 and then down and around the periphery of the pressure roller44. The pressure roller 44 preferably is mounted in bearing blocks 53 which are vertically slidable in ways 54 under the control, for example, of vertical feeding screws 55. The web of paper 43 is drawn off the paper roll 51 and led between rollers 56 and 57 and thence over the periphery of the roller 45 into engagement with the web of paper 42 as it passes over the roller 44. The roller 57 is a coating roller engaged with the surface of the web 43 for the purpose of spreading on such surface a thin layer of coating or adhesive material such as asphalt which may be transferred to the surface of the roller 57 from a heated supply 58 through the medium of intermediate rollers 59. The asphalt or other coating mate: rial is spread over the surface of the web 43 in order to adhere the webs 42 and 43 to each other, to hold the reinforcing strands in place and, if a proper material is used, to render the final reinforced laminated paper waterproof. Such waterproofed reinforced papers frequently are used for packaging articles and materials which may be harmed by moisture or other substances during shipment or storage as, for example, for the overseas shipment of materials easily corroded by sea air.
The upper roller 44 is adjusted by means of screws 55 or by similar mechanism, to squeeze the two webs of paper 42 and 43 together between the rollers 44 and 45 so that the thickness of the asphalt spread on the web 43 is reduced to a desired value, probably just sufficient to embed the reinforcing strands 15 and, in many instances, to prevent the paper webs from being rendered irregular on their surfaces due to the random overlapping of the reinforcing strands. When desired, the thickness of the layer of coating may be increased or decreased to accommodate strands of varying diameters or to actually embed the strands themselves in the paper webs. If, for example, the reinforcing material consists of strands of a hard substance such as glass, it may be desirable to maintain the thickness of the coating layer atslightly less than the average of the overlapped glass strands and thus to actually emboss the strands into the paper webs to some desired extent. The thickness of the asphalt coating must, of course, be carefully controlled in order to prevent the crushing of the reinforcing fibers. Where organic fibers such as sisal, ramie or hemp or cotton, linen or other soft materials are used, the spacing between the rollers 44 and 45, and the pressure thus acting against the laminated structure formed therebetween, may be so controlled as to tend to flatten the fibers when desired.
Other reinforcing materials and other sheet materials may be used in combination with those mentioned or in other combinations to produce finished laminated sheets of desirable characteristics. As examples, combinations of materials such as glass and wool, or nylon and wool, or cotton and burla may be stranded to give desired strength or other characteristics. Wholly synthetic fibers, such as nylon monofilaments, rayon threads or yarns or strands or combinations thereof may also be handled.
Similar variations in the material from which the sheets are made and in the coating or adhesive materials also are possible. For example, it may be desirable to stiffen the laminated structure as well as reinforce or moistureproof it. In such a case, the coating material may he one that sets up into a stiff layer, for example animal glue, water glass, synthetic resin, or other substance. The affinity of certain adhesive and coating compounds to certain fibrous materials may be taken into consideration to produce still other results.
The pressure rollers 44 and may be provided with heating means for instance where laminated sheeting is to be fabricated from heat softenable materials such as uncured rubber or synthetic resins or plastics. In these cases, separate coating materials might not be necessary, the heat of the rollers 44 and 45 serving to fuse the two webs of thinner material together around the reinforcing strands, forming an integral final structure in which the strands are embedded. Such an operation would be useful in making reinforced rubber sheeting, for example.
Sheets of heat softening material may be laminated with other materials by heating only one of the two rollers and the strands in such cases may be adhered by the sheet material itself or by adhesive material introduced as shown. Decorative sheet materials may be produced, as by using reinforcement of one color, a
transparent sheetand an opaque sheet of another color.
The strands 15 probably are deposited directly on the coated surface of the lower web 43 in most instances; although, of course, because of the random convolutions of the strands, it is possible that some of the strands may not be pressed into contact with the coating until the upper web 42 is laid over them and the two webs with the interlaid coating and strands pass between the pressure rollers 44 and 45. The general nature of the random pattern in which the strands 15 are laid upon the coated web 43 is apparent from Fig. 2 where each strand is shown as generally overlapping at irregular places its neighboring strands. Figs. 6 and 7, which are greatly enlarged, are copies from laminated paper fabricated as explained above and show the pattern actually assumed by glass yarns or strands deposited between webs of paper by a machine such as that illustrated in the drawings. It will be seen in Fig. 6 that many strands overlay others, either the same strand or neighboring strands and thus the average thickness of the reinforced layer probably is between 1 and 1 /2 times the diameter of the individual yarns or strands employed for reinforcement. The average thickness of the layer may be controlled not only by the spacing between the pressure rollers 44 and 45 and by the pressure placed on the roller 44 but also by varying the relative linear speeds of the strands 15 through their nozzles 33 and the 'webs 42 and 43 of material being reinforced. If the webs are increased in linear speed relative to the strands the convolutions of the strands are, of course, elongated and less time is allowed during which the strands may overlay each otherj Conversely, if the speed of the webs is reduced relative to the speed of deposition of the strands 1 5, the convolutions of the strands become more complex and there results a greater amount of reinforcement per linear measurement of the sheet material. Thus by the setting of the variable speed mechanism 22 the feed of the strands can be selected with respect to any given linear speed of the pressure rollers 44 and 45 and the webs of paper 42 and 43, to establish a desired percentage by weight between paper and coating and reinforcing material and the average strength of the re inforced paper can be controlled.
After the two webs of paper 42 and 43 pass between the pressure rollers 44 and 45, they are united into a laminated reinforced paper and pass as a single web between feeding rollers 61 and over rollers 62 between which they may be draped, as in loops 63, for a period of time suflicient to allow the drying or setting up of the asphalt or other adhesive material. The sheet 60 of laminated paper may then be wound on a roll 64, for example, by a pair of parallel driven rollers 65.
a The construction of the mechanism designed to feed the individual strands 15 off their spools 10 and to the nozzles 33 and comprising the three peripherally engaged wheels or rollers 17, 25 and 29, has many advantages. The fact that the axes of the two feeding rollers 25 and 29 lie in advance of the axes of the roller or wheel by which they are driven (i. e., the wheel 17 and roller 25 respectively), practically eliminates bumping or irregular engagement. Mounting the feeding rollers 25 and 29 on the ends of individual rocker arms 26 and 30 not only permits this construction but it has other advantages. If the wear on the surfaces of the rollers 25 and 29 or on a driving wheel 17 or on the tires on such wheel and rollers is not the same as it may be on others,
, the fact that each of the lower feeding rollers 25 is independently mounted on its own rocker arm 26, permits that roller 25 to independently follow the periphery of its driving Wheel without affecting the operation of other ones of the feeding rollers 25 in the machine. This also is true with respect to the upper feeding rollers 29.
As is indicated by the broken section in Figs. 2 and 3, a machine embodying the invention or a machine designed for the practice of the method of the invention may have considerable width for supplying reinforcing material to webs of sheet material of considerable widths. However, it may be desired to reinforce a web narrower than the maximum size for which the machine is designed. Under these conditions only that number of strands required to adequately cover the surfaces of the webs to be reinforced need be employed. The idle feeding devices may be disengaged and wear on the peripheries of the several Wheels and rollers eliminated by swinging the upper feeding roller 29 upwardly on its -7 arm 30- out of engagement with its associatedv feeding roller 25 and then swinging the lower feeding roller-25 on its arm 26 upwardly out of engagement with its associated driving wheel 17.
The provision for simple disengagement of each set of feeding rollers 25 and 29 greatly facilitates the insertion of a strand 15 either before or during a run-of reinforcing paper. If, for example, a strand 15 should be broken as by becoming snarled or jamming at its spool 10, the operation of the machine as a whole need not be stopped because an operator can quickly flip up the upper feeding roller 29 and reinsert the end of the strand into the associated nozzle 33, then re-engage the upper feeding roller 29 for continuing the feed of the strand.
Where a strand is fed between the surfaces of two rollers, there may from time to time, be a tendency for the strand to wrap around one or the other of the rollers. lf this occurs, the operator can easily disengage the roller involved (by swinging it out of driving engagement) and re-feed the strand without disturbing the operation of other strand feeding mechanisms. The arrangement of the two web feeding pressure rollers 44 and 45 with their axes parallel and thus with the converging space between the surfaces of the two webs 42 and 43 open for the reception of the projected strands, makes possible the several advantages discussed earlier. The simplification of the control of thickness of the layer of asphalt or other adhesive coating and/or waterproofing material, permits a close control of the finished laminated paper from a standpoint of its overall thickness and surface condition without resulting in the accumulation of the excess asphalt, for example, at an inaccessible portion of the machine as probably would be the case were pressure rollers located at a more remote point. Similarly, the thickness of the coating substance with respect to the average thickness of the layer of reinforcing material can be controlled directly at the point where the strands are being interlaid. When the sheet material is fused by the rollers to receive or adhere the reinforcing strands, the fusing, interlaying and laminating all are substantially simultaneous for ease of control. Observation-of all of the above operations is facilitated by the location of these cooperating rollers where the assembly of all of the elements of the finished laminated sheet takes place.-
The word strands as used herein and in the claims which follow, has been selected to cover an individually handled group of fibers or a single fiber as, for example, a monofilament of substantial cross section or more than one group of fibers as, for example, where several yarns or threads might be handled by each of the individual feeding mechanisms and it is to be understood that the word strands as so used is not intended to be limited to a single thread, yarn or filament of fibers.
'Although the operation of the apparatus has been explained in connection-with its employment for the reinforcing of paper with strands of glass fibers, it is to be -8 understood, of course, that it is equally adaptable for the reinforcement of other sheet material with strands of fibers of other material and its operation is equally useful under these other conditions.
1. A random pattern strand feeding machine for use in laying reinforcing material on a continuous web of sheet material, said machine comprising, in combination, means for supporting a supply of strands; a plurality of individual strand feeding mechanisms arranged adjacent each other transversely of the direction of movement of the sheet to be reinforced, each of said mechanisms including a. pair of coacting vertically arranged feeding rollers ournalled on parallel horizontal axes with their peripheries in line of engagement, a mounting arm for each of said rollers, said arms being pivoted on horizontal axes and adapted to be swung upwardly to separate said rollers, the upper one of said rollers being urged downwardly toward peripheral engagement with the lower one of said rollers, and a driving wheel having a fixed axis and peripherally engaging the lower one hf said feeding rollers when said lower feeding roller s swung downwardly on its arm; a variable speed power device for rotating all of said driving wheels at the sanie speed; and a plurality of individual strand, air blast feeding nozzles, eachof said nozzles having a longitudinal orifice into which a strand is fed from the associated one of said feeding mechanisms and out of which such strand is projected by the air blast toward and onto the web of the sheet to be reinforced at a linear speed in excess of that of the sheet.
2. A machine in accordance with claim 1 in which the axis of rotation of the lower one of the feeding rollers hes in a vertical plane ahead of the vertical plane of the axis of the driving wheel when the peripheries thereof are engaged and the axis of the upper one of said feeding rollers lies in a vertical plane ahead of the vertical plane of the axis of the lower one of said feeding rollers when said feeding rollers are in feeding position with the strand to be fed lying between the peripheries of said feeding rollers.
3. A machine in accordance with claim 1 in which the supply of strand, the point of engagement of the strand betwen the peripheries of the feeding rollers and the orifices in the air blast nozzles lie in substantially the same horizontal and vertical planes.
References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,085,908 Hoe Feb. 3, 1914 1,914,801 Chadwick June 20, 1933 1,981,229 Gillet Nov. 20, 1934 2,130,520 Bockius Sept. 20, 1938 2,392,882 Roberts Jan. 15, 1946 2,489,242 Slayter et al Nov. 22, 1949