US3339357A

US3339357A - Process and apparatus for producing impregnated fiber material

Info

Publication number: US3339357A
Application number: US434139A
Authority: US
Inventors: Marzocchi Alfred; Lorraine C O'flahavan
Original assignee: Owens Corning Fiberglas Corp
Current assignee: Owens Corning
Priority date: 1965-02-19
Filing date: 1965-02-19
Publication date: 1967-09-05
Anticipated expiration: 1984-09-05

Description

Se t. 5, 1967 A. MARZOCCHI ETAL 3,339,357

PROCESS AND APPARATUS FOR PRODUCING IMPREGNATED FIBER MATERIAL Filed Feb. 19, 1965 2 Sheets-Sheet 1 JAMES M OHAH/WA/V K015654550) A T TOR/V5 vs PROCESS AND APPARATUS or: PRODUCING IMPREGNATED FIBER MATERIAL Filed Feb. 19, 1965 Sep 5.. 6 'A. MARZOICCHI ETAL 2 Sheets-Sheet 2 a w m ,4 M m 3 CW5 y @M M f m Q Mm 0 40 W 0 M k C A 5W W TM m N B a e PVEESO NZ L A Y Ad h United States Patent 3,339,357 PROCESS AND APPARATUS FOR PRODUCING IMPREGNATED FIBER MATERIAL Alfred Marzocchi, Cumberland, R.I., and James M.

OFlahavan, deceased, late of Manville, R.I., by Lorraine C. OFlahavan, administratrix, West Chelmsford, Mass., assignors to Owens-Corning Fiberglas Corporation, Toledo, Ohio, a corporation of Delaware Filed Feb. 19, 1965, Ser. No. 434,139 12 Claims. (Cl. 57-35) ABSTRACT OF THE DISCLOSURE An apparatus for impregnating twisted yarns which includes rotatably mounted means for contacting a section of the twisted yarn to cause the fibers of the section to assume a generally exposed untwisted condition and subsequently for contacting the untwisted fibers of the section of said strand to cause the fibers of the section to assume their initial untwisted condition, and means for applying an impregnating fluid to the fibers of the yarn while in their exposed untwisted condition.

The present invention relates to a process and apparatus for producing an impregnated fiber material, but more particularly it relates to a method and apparatus for impregnating and coating the fibers of a composite twisted yarn of fibers of a high strength material with a fluid material capable of controlled solidification.

The invention particularly lends itself to a process for the continuous production of textile strand structures consisting of either continuous filament or stable fibers and a flexible synthetic resin, which are suitable for end uses requiring high tensile strength, resistance to abrasion, corrosion and electrical conduction, resistance to mildew, rot and staining and has adaptability for direct substitution in existing machinery for the fabrication of end products.

It is well known that glass fibers have many inherent characteristics which are desirable for textile purposes, among which are inertness to deterioration of the base material, high tensile strength and a high modulus of elasticity. However, if glass fibers are for-med into a composite twisted strand or yarn, it is necessary to provide a protectivecoating for the fibers which will function to protect the usually low abrasion-resistant glass filaments and to limit the inter-filament abrasion so as to impart a longer life to the composite structure than is otherwise obtainable with bare glass fiber yarns. Because of interfilament abrasion, the flex life of bare glass fibers is extremely limited. In addition to being limited by high inter-filament abrasion, the flex life of bare glass fiber strands and yarns is short because of the crushing effects of localized stress concentration and the lack of means effecting stress relief.

In order to effect efiicient impregnation of the twisted strands or yarn with the protective coating, it has been found desirable to untwist the yarn or strands more or less to expose all of the individual fibers of the composite structure prior to or simultaneously with the impregnation thereof. Then, after impregnation of the strands or yarn, it is desirable once again to effect the twist thereto prior to the solidification of the impregnating material.

3,339,357 Patented Sept. 5, 1967 In view of the foregoing discussion, it is an object of the present invention to produce a process and apparatus for impregnating the twisted strands or yarns of fibrous material which includes means for untwisting the fibrous material to expose the substantial portion of the fibers thereof, applying a protective coating to the exposed fibers, and retwisting the material before the protective coating solidifies.

Other objects and advantages of the invention will become manifest from considering the following description of several embodiments thereof in the light of the accompanying drawings, in which:

FIGURE 1 is a perspective view of apparatus for impregnating twisted tsrand or yarn;

FIGURE 2 is an enlarged fragmentary view of the apparatus illustrated in FIGURE 1 for untwisting the strand or yarn, applying the protective coating thereto, and retwisting the strand or yarn;

FIGURE 3 is a sectional view of the apparatus illustrated in FIGURE 1 taken along line 3-3 thereof;

FIGURE 4 is a perspective view of a modified form of the apparatus illustrated in FIGURES 1 to 3;

FIGURE 5 is a perspective view of apparatus similar to that illustrated in FIGURES 1 to 3 but showing a further modified apparatus designed for carrying out the process of the invention;

FIGURE 6 is a perspective view of another modified apparatus capable of carrying out the process of this invention; and

FIGURE 7 is a perspective view of apparatus similar to the apparatus illustrated in FIGURE 6 wherein the contact elements are disposed to peripheral contact with the textile fiber strand being treated.

Referring to FIGURES 1, 2 and 3 there is illustrated one of the preferred embodiments of the invention wherein there is a supply package 10 containing twisted yarn or twisted strands 12 of textile fibers. For the purposes of the following description, the terms yarn or strands include textile fibers which are made typically from two basic forms: either continuous filament or staple fiber which has been twisted prior to being wound upon the package by any of the well known procedures of the type employed in the textile industry. The difference between continuous filaments and staple filaments can best be illustrated and described with reference to the glass fiber industry, although it will be understood that the present invention is likewise advantageously used in treating other textile fibers, such for example as natural fibers like cotton, or synthetic materials such as nylon and Dacron and others. Accordingly, the difference between continous filaments and staple filaments is the manner in which they are drawn from the furnace. Both forms begin with the same manufacturing process. Various ingredients are mixed together to make a batch of a specified formulation. The batch is then fed into a furnace where it is melted at high temperatures to form glass. Then, precisely controlled filaments are attenuateddrawn or pulled rapidly-from the molten glass. These filaments may then be sized and wound on packages ready for further fabrication. The continuous filament is an individual fiber of a continuous filament strand which is typically composed of many continuous fine filamentsfrom 51 to 408depending upon the specific requirements. These continuous filaments are drawn from the furnace at a speed of more than two miles a minute. A staple fiber is an individual fiber8 to 15 inches long-which is formed by jets of air which pull the glass filaments from the furnace and gather them into a strand on a revolving drum.

The twisted yarn 12 is directed along a path in the direction of the arrow A, A (FIGURES 1 and 2) and caused to be paid off of the supply package and wound upon another take-up package 14 similar to package 10. Intermediate the supply package 10 and the take-up package 14, there is disposed a pair of

contact elements

10 and 18 having driving

shafts

20 and 22, respectively. The driving

shafts

20 and 22 are coupled to a source of power (not shown) capable of imparting rotary movement to the

contact elements

16 and 18 in such a manner that the elements rotate in opposite directions. Substantially flat contact surfaces 24 and 26 are provided on the adjacent surfaces of the

contact elements

16 and 18, respectively. The rotating

contact elements

16 and 18 are partially overlapped and have their respective contact surfaces 24 and 26 spaced adequately from one another to provide an engaging passage of the yarn 12 therebetween.

A coating material or impregnant is applied to the contact elements by means of a pair of

spray nozzles

28 and 30, the former being directed to apply the impregnant to the contact surface 24 of the element 16, while the latter is directed to apply the impregnant to the contact surface 26 of the element 18. The contact surfaces 24 and 26 may be surfaced wih a felt-like or napped material in order to enhance both the characteristic of the surfaces to carry the impregnating material to the yarn being treated and the tractive effect of the surfaces upon the yarn being treated, as will be explained in greater detail hereinafter. Both liquid coating and impregnating materials, such as resin plastisols and particulate substances, such as cotton linters, alumina, carbon black, etc. may be applied to the contacting surface of the rotating elements.

It has been found that plastisols or organsols such as those formed from polyvinyl chloride embody suitable characteristics for use in the method and apparatus herein described and illustrated. Also, latices or elastomeric compositions such as a copolymer of the vinyl pyridine and a condensate of resorcinol and formaldehyde which yields a latex having approximately 30% solids has been found useful and is particularly advantageous for impregnating fibrous yarns which are designed for reinforcement of natural rubber stock.

It will be manifest to those skilled in the art that the

spray nozzles

28 and 30 are coupled to a source of coating material (not shown) which is typically maintained under pressure and a controlled amount thereof is allowed to flow to the nozzles by suitable metering valve means (not shown).

In operation, the yarn 12, which is shown on the drawing (FIGURES 1 and 2) as having an S twist, is caused to be passed along a path between the overlapped revolving

elements

16 and 18 which are rotating in the direction of the arrows. The rotating contact surfaces 24 and 26 contact opposite surfaces of the yarn and apply forces thereto which act against the forces of sizing material which was applied to the fibers when the yarn was initially formed and twisted. Thus, the yarn 12 is untwisted from its normal set condition by the cooperative action of the

counter-rotating elements

16 and 18. In untwisting the structure of the yarn 12 from the original twisted condition tends to flatten out the yarn and more or less expose all of the fibers of that section of the yarn within the zone defined by the overlapping of the elements.

Since the contacting surfaces 24 and 26 of the

elements

16 and 18 are saturated with the selected impregnant, a certain portion of the impregnant is deposited on the exposed surfaces of the fibers as the contact surfaces pass over the multitude of fibers of the yarn. As the yarn 12 passes the midpoint of travel within the zone defined by the overlapped sections of contact surfaces, the forces caused by the cooperating

counter-rotating elements

16 and 18 reverse and tend to retwist the yarn into its original configuration. When the yarn 12 has completed its travel. between the counter-rotating elements, it is completely retwisted into its original set condition with the individual fibers being coated with the impegnant to a degree determined by the amount of impregnant which is applied to the contact surfaces by the nozzle arrangement per unit of time.

After the above described impregnating and coating operation, the curing or setting of the impregnant is achieved by causing the yarn 12 to travel a sufiicient distance to allow the impregnant to solidify or polymerize as the case may be. The system could employ a sizing or curing oven through which the yarn would be caused to travel after being impregnated but before being applied to the package 14.

In the light of the above description, it will be manifest that the initially twisted fibrous product, for example glass fiber filaments, is untwisted against the forces of the original sizing material, to expose a substantial portion of the fibers thereof. The product is maintained in the untwisted condition while the impregnant is applied to the exposed fibers and thereafter forces are applied to cause the product to approach or assume its original twisted condition. Subsequently, the impregnant is allowed to cure or set, resulting in a composite twisted product wherein the fibers are substantially coated with the desire-d impregnating material.

Similar results may be achieved with the apparatus disclosed in FIGURE 4 wherein therein there is a twisted yarn product 32 comprised of textile fibers of the type explained in detail in connection with the method and apparatus illustrated in FIGURES l, 2 and 3. The twisted yarn 32 is passed through a pair of guiding

eyelets

34 and 36 which are arranged to guide the yarn in the direction of the arrows B-B' across the contact surface 38 of a rotating element 40. The element 40 has an integral driving shaft 42 which is coupled to a source of energy capable of imparting rotation thereto.

It will be understood that as the yarn 32 contacts the upper peripheral edge portion of the contact surface 38, forces are applied to the yarn to cause the same to be untwisted. Then, as the yarn travels downwardly, it is untwisted more completely to expose the interior fibers and as the yarn travels through the horizontal plane of the rotating axis of the contact surface 38, the forces applied to the yarn tend to retwist the yarn to its initial twisted form.

When the yarn 32 is untwisted by the frictional engagement of the rotating surface 38, a spray nozzle 44 is directed to apply an impregnant on the exposed fibers of the yarn 32, as illustrated in FIGURE 4, Also, it must be recognized that the guiding

eyelets

34 and 36 are disposed in such a fashion that the yarn passing therethrough is caused to travel along a path which will enable adequate frictional engagement between the yarn 32 and the rotating contact surface 38 of the element 40. In certain instances, the

eyelets

34 and 36 may be adjustably mounted to accommodate yarns of various types and diameters.

FIGURE 5 illustrates a modified form of the apparatus for applying the impregnant to the yarn when it is in the untwisted condition. The appratus includes a pair of partially overlapping

rotating elements

47 and 48 having integral driving shafts 50 and 52, respectively, which are adapted to operate in the same manner as the corresponding elements illustrated in FIGURES 1, 2 and 3. However, in this instance, the rotating elements are immersed in a tank or container 60 containing a fiuid impregnating material 62. The twisted yarn 46 is introduced into the impregnating material 62 and caused to be held immersed therein by a pair of spaced rotatably mounted

guide rods

64 and 66. The contact surfaces of

rotating elements

47 and 48 effectively apply frictional force to the twisted yarn as it passes therebetween and thereby permits the impregnating fluid 62 to coat the exposed surfaces of a substantial portion of the fibers which make up the composite yarn 46.

It will be observed that the yarn 46 travels in the direction of the arrows C-C and is actuated by any suitable means such as having the take-up package (not shown) power driven, while the supply package (not shown) disposed at the inlet side of the container 60 is freely rotatable allowing the yarn 46 to be removed therefrom.

FIGURE 6 shows a further modified form of the apparatus for untwisting and impregnating textile fiber yarn materials wherein there is a pair of spaced oppositely rotating frusto-conically shaped elements 76 and 78 having suitable driving shafts therefor. The twisted textile fiber yarn 72 is guided in the direction of the arrows D-D' across the contact surfaces 84 and 86 of the elements 76 and 78 respectively by a pair of spaced guiding members 80 and 82. As the yarn 72 is caused to travel over and across the rotating contact surface 84, frictional forces are applied to the yarn 72 which tend to untwist the yarn to expose a substantial portion of the fibers thereof. Thereafter spray nozzles 88 and 90 are'arranged to direct an impregnating fluid upon the exposed fibers. After the fibers are adequately coated, the untwisted yarn passes in frictional engagement over the rotating contact surface 86 of the rotating element 78 which effectively applies forces to the yarn tending to retwist the yarn 72 so that it returns to its original twisted condition. Due to the oppositely inclined disposition of the contacting

surfaces

84 and 86, the transient yarn 72 is maintained centrally of the ends of the elements thereby retaining the yarn centered throughout its travel between the guiding means 80 and 82.

A further modied form of the invention is illustrated in FIGURE 7 wherein a normally twisted textile fiber yarn 92 is caused to travel from a supply package (not shown) to a take-up package (not shown) in the direction of the arrows E-E' across the rotating peripheral contacting

surfaces

94 and 96 of spaced oppositely

rotating elements

98 and 100. The

rotating elements

98 and 100 are typically caused to rotate in the direction of the arrows on the respective elements.

The contact surface 94 is effective to apply frictional forces to the twisted yarn 92 to cause the yarn to untwist from its normal set condition and thereby expose a substantial portion of the fibers which comprise the yarn. A spray nozzle 102 is disposed to apply a fluid irnpregnant to the exposed fibers of the yarn and thereafter the contact surface 96 which is rotating in an opposite direction from the direction of the contact surface 94 applies frictional forces to the yarn 92 causing the same to be returned to its normal twisted state.

It will be understood from the foregoing description that we have provided an improved method of impregnating twisted strands or yarns of fibrous material and a number of new and improved devices for accomplishing the method. The method and apparatus are clearly universal in their application and may be satisfactorily employed for the treating or handling of many fibrous materials other than glass fibers.

It will be understood that changes may be made in the method of the invention and the associated apparatus without departing from the spirit of the invention especially as defined in the following claims.

What we claim is:

1. Apparatus for impregnating a normally twisted strand of textile fibers comprising:

means for directing the twisted strand along a path;

a pair of contact counter-rotatin g elements having strand contact surfaces mounted to rotate about spaced parallel axes, the contact surface of one of said con- 6 tact elements contacting a portion of the twisted strand and the contact surface of the other of said contact elements contacting at least a downstream portion of the twisted strand;

means for imparting counter rotation to said contact element; and

means for applying an impregnating fluid to the fibers of said strand while it is in the untwisted condition, whereby the contact surface of said one of said said contact elements untwists the strand to expose the fibers thereof as it travels thereacross and the contact surface of said other of said contact elements causes the strand to return the yarn to its normally twisted condition.

2. Apparatus for impregnating a normally twisted strand of textile fibers as defined in claim 1 wherein the contact surfaces of said contact elements are of substantially planar disk-like configuration.

3. Apparatus for impregnating a normally twisted strand of textile fibers as defined in claim 2 wherein the contact surfaces of said contact elements are arranged to at least partially overlap one another.

4. Apparatus for impregnating a normally twisted strand of textile fibers as defined in claim 2 wherein said contact surfaces of said contact elements are disposed peripherally thereof.

5. Apparatus for impregnating a normally twisted strand of textile fibers as defined in claim 4 wherein said contact elements are mounted to rotate about the same axis.

6. Apparatus for impregnating a normally twisted strand of textile fibers as defined in claim 1 wherein the contact surfaces of said contact elements are of substantially conical configuration.

7. Apparatus for impregnating a normally twisted strand of textile fibers as defined in claim 1 wherein said means for applying an impregnating fluid includes a bath of fluid in which said contact elements are immersed.

8. Apparatus for impregnating a normally twisted strand of textile fibers as defined in claim 1 wherein said means for applying an impregnating fluid includes means for spraying the fluid onto the fibers of the untwisted strand.

9. Apparatus for impregnating a twisted strand of textile fibers comprising:

means directing the twisted strand along a path;

rotatably mounted means for contacting a section of the twisted strand to cause the fibers of said section to assume a generally exposed untwisted condition and subsequently for contacting the untwisted fibers of the section of said strand to cause the fibers of said section to assume their initial twisted condition; and

means for applying an impregnating fluid to the fibers of said section while in their exposed untwisted condition.

10. Apparatus for impregnating a twisted strand of textile fibers as defined in claim 9 wherein said rotatably mounted means for contacting a section of the twisted strand includes a substantially fiat strand contacting surface disposed to rotate within a plane substantially parallel to the path of said strand.

11. Apparatus for impregnating a twisted strand of textile fibers as defined in claim 10 wherein the axis of rotation of said contacting surface is offset from the path of said strand.

12. A method for impregnating a twisted strand of textile fibers including:

directing a twisted strand of yarn along a path;

applying a first force to said yarn to untwist a section thereof to expose the substantial portion of fibers in V said section;

impregnating said yarn while in the untwisted state with a fluid material capable of controlled solidification; and

7 thereafter applying a second force to the untwisted section of said yarn downstream of said first force causing said yarn to return to its original twisted state before the impregnating fluid solidifies.

References Cited UNITED STATES PATENTS 1,745,285 1/1930 Whifi'en 118-420 X 2,577,793 1/1951 Miller 57164 X Hansen 5777.4 X

Horn 5735 X Tissot et a1 57157 Fox 118-420 X Cecchi 57-35 Van Dijk et a1 5777.5 Gori 5735 FRANK J. COHEN, Primary Examiner.

J. PETRAKES, Examiner.

Claims

1. APPARATUS FOR IMPREGNATING A NORMALLY TWISTED STRAND OF TEXTILE FIBERS COMPRISING: MEANS FOR DIRECTING THE TWISTED STRAND ALONG A PATH; A PAIR OF CONTACT COUNTER-ROTATING ELEMENTS HAVING STRAND CONTACT SURFACES MOUNTED TO ROTATE ABOUT SPACED PARALLEL AXES, THE CONTACT SURFACE OF ONE OF SAID CONTACT ELEMENTS CONTACTING A PORTION OF THE TWISTED STRAND AND THE CONTACT SURFACE OF THE OTHER OF SAID CONTACT ELEMENTS CONTACTING AT LEAST A DOWNSTREAM PORTION OF THE TWISTED STRAND; MEANS FOR IMPARTING COUNTER ROTATION TO SAID CONTACT ELEMENT; AND MEANS FOR APPLYING AN IMPREGNATING FLUID TO THE FIBERS OF SAID STRAND WHILE IT IS IN THE UNTWISTED CONDITION, WHEREBY THE CONTACT SURFACE OF SAID ONE OF SAID SAID CONTACT ELEMENTS UNTWISTS THE STRAND TO EXPOSE THE FIBERS THEREOF AS IT TRAVELS THEREACROSS AND THE CONTACT SURFACE OF SAID OTHER OF SAID CONTACT ELEMENTS CAUSES THE STRAND TO RETURN THE YARN TO ITS NORMALLY TWISTED CONDITION.

12. A METHOD FOR IMPREGNATING A TWISTED STRAND OF TEXTILE FIBERS INCLUDING: DIRECTING A TWISTED STRAND OF YARN ALONG A PATH; APPLYING A FIRST FORCE TO SAID YARN TO UNTWIST A SECTION THEREOF TO EXPOSE THE SUBSTANTIAL PORTION OF FIBERS IN SAID SECTION; IMPREGNATING SAID YARN WHILE IN THE UNTWISTED STATE WITH A FLUID MATERIAL CAPABLE OF CONTROLLED SOLIDIFICATION; AND THEREAFTER APPLYING A SECOND FORCE TO THE UNTWISTED SECTION OF SAID YARN DOWNSTREAM OF SAID FIRST FORCE CAUSING SAID YARN TO RETURN TO ITS ORIGINAL TWISTED STATE BEFORE THE IMPREGNATING FLUID SOLIDIFIES.