US3021255A - Method of and machine for forming strips of material from wet mixes, including fibers - Google Patents

Description

Feb. 13, 1962 A. D- SIMPSON 3,021,255 METHOD OF AND MACHINE FOR FORMING STRIPS OF 4 MATERIAL FROM WET MIXES, INCLUDING FIBERS 2 Sheets-Sheet 1 Filed June 27, 1958 INVENTOR.

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Feb. 13, 1962 A. D. SIMPSON 3,021,255 METHOD OF AND MACHINE FOR FORMING STRIPS OF MATERIAL FROM WET MIXES, INCLUDING FIBERS Filed June 27, 1958 2 Sheets-Sheet 2 INVENTOR.

3,021,255 METHOD OF AND MACHINE FOR FORMING STRIPS F MATE FROM WET MDiES, IN- CLUDENG FIBERS Alvan D. impson, Plainfield, N..I., assignor to The Forming Machine Company of America, Inc, Bound Brook, N.J., a corporation of Delaware Filed June 27, 1958, Ser. No. 744,940 7 Claims. (Cl. 162-156) This invention relates in general to the formation of strips of compositions of matter including fibers, for example, mixtures of glass fibers or filaments and synthetic resinous materials such as vinyl compounds; and more particularly the invention is directed to the production of such strips from mixes including a fibrous material such as glass fibers and a liquid such as Water, with or without other materials such as synthetic resinous compositions.

It is desirable that strips of material of this nature shall have the fibers matted in or extending in different directions in relatively overlapping or overlying relation, but it has been found that in attempting to produce such strip material from wet mixes, the fibers, and particularly glass fibers, tend to attract and adhere to each other in side by side relation and extend in the same general direction. Furthermore, the difficulty is aggravated by attempting to pass the mix through pipes or pumps or beaters because the fibers tend to fiocculate and prevent the formation of a strip in which the fibers are uniformly distributed.

A primary object of the present invention is to provide a novel and improved method and machine or apparatus for forming strips of material of the general nature described from wet mixes comprising fibers and liquids wherein the fibers shall be matted or disposed in crossed and overlapping relation to each other throughout the strip.

The invention also contemplates the formation of such a strip of fibrous material by depositing the solid material or fibers from the mix on a foraminous wall or screen, for example, as shown in my Patents No. 2,581,210 and No. 2,737,858; and another object of the invention is to provide a novel and improved method and means of forming the mix and feeding it to the forming screen with the fibers, particularly glass fibers, distributed haphazardly or in crisscross relation to each other throughout the mix.

A further object is to provide such a method and machine for feeding the fibers into the liquid in such a manner that the fibers are thoroughly dispersed or distributed at random throughout the mix and the mix shall be quickly fed to the point of deposit, such as a form screen, with a minimum of disturbance of the mix such as might be caused by strong currents or movement of the mix under pressure around sharp bends or through pumps.

Still another object of the invention is to provide apparatus for forming and feeding a wet mix, including glass fibers, which shall be devoid of pumps, mechanical agitators, long pipe runs and high velocities, and sharp turns in the flow of the mix to the forming element, whereby the tendency of the glass fibers to bunch up or stick together in parallel relation to each other or to fiocculate, is minimized.

Other objects, advantages, and results of the invention will be brought out by the following description in conjunction with the accompanying drawings in which FIGURE 1 is a partial side elevation and partial vertical sectional view of a machine for carrying out or practicing the invention;

' FIGURE 2 is a fragmentary transverse, vertical sectional view on the plane of the line 2-2 of FIGURE 1;

Stars act FIGURE 3 is a horizontal sectional view on the plane of the line 33 of FIGURE 2; and

FIGURE 4 is a view similar to FIGURE 1 showing a modification of the invention.

Specifically describing the embodiment of the invention illustrated in FIGURES 1 to 3 inclusive, I have shown a forming machine A of the same type as that disclosed in my Patent No. 2,581,210, which includes a tank in which is rotatably mounted about a horizontal axis, a hollow cylindrical rotor drum B carried by hollow trunnions 2 which are journaled in any suitable manner, for example, in bearings 2a, and are driven by any suitable source of power. The drum has a foraminous or screen-like peripheral wall 3 and is located in the tank so that the lower portion thereof will be submerged in the mix 4 that is disposed at the lower portion of the tank and fiows into the tank by gravity through an inlet pipe 5. Upon rotation of the drum in the direction indicated by the arrow in FIGURE 1, the liquid from the mix 4 will flow through the interstices in the screen 3 so as to cause a depositt of some of the fibers from the mix on the screen, and as the drum continues to rotate, this deposited solid matter is elevated out of the mix to the upper portion of the tank, which provides an upper chamber where the liquid drains from the deposited layer 6 downwardly into the drum from whence the liquid is drained off in any suitable manner as by suction pipes 7 extending into the drum through the hollow trunnions.

The deposited layer 6 is removed from the tank through an opening 8 in the wall of the tank above the level of the mix, and the spaces between the drum and the Walls of the tank at the edges of the opening are suitably sealed, for example, by means shown in my Patent No. 2,7 23,599. For illustration, I have shown a roller 9 at each end of the opening journaled in the tank which is contacted by a rubber strip 10.

Gas under pressure in excess of atmospheric pressure is supplied to the tank A above the level of the mix, for example, from a suitable pump through a pipe 11, and this pressure will be continuously exerted on the surface of the mix tending to accelerate the fiow of liquid from the mix through the drum and at the same time force the liquid from the deposited layer 6 on the upper portion of the drum.

This forming machine is simply illustrative of any suitable apparatus for handling the wet mix 4, and the invention is directed to the method and means for forming the mix and feeding it to the forming machine or other point at which the mix is to be operated upon.

As hereinbefore pointed out, the invention especially contemplates wet mixes, including glass fibers and filaments dispersed and suspended in a liquid. In accordance with the invention, short lengths of dry glass fibers or filaments are dropped in haphazard or random manner into the liquid of the mix and the mix is quickly conducted to the forming element with a minimum of agitation of the mix.

As shown in FIGURE 1, the glass fiber may be pro vided in spools C that may be journaled in any suitable manner, for example, on spindles 12 on a fixed support.- ing bracket 13. One or more spools may be utilized and the fibers therefrom may be passed through guides 14 and between feeding rollers 15 and 16 which pull the fibers between them from the spools C and one of which cooperates with a cutter roller 17 for cutting or breaking the fibers into short lengths or pieces 18. The fiber cutting mechanism may be of any suitable form, but as shown, the roller 17 has blades 19 between which and the periphery of the roller 16, the fibers are cut or broken. As shown, the roller 17 is driven from a suitable source through a shaft 20 and the rollers 15 and 16 are driven from said shaft from a suitable gear train 21. It will be noted that the short lengths of the fibers 18 leave the cutter in a haphazard manner and fall by gravity freely through the atmosphere into the liquid 22 of the mix which is contained in a tank 23 on which the fiber cutting mechanism and the guide 14 may be mounted for convenience above the liquid level of the mix. The fibers thus fall into the liquid and extend in different directions in crisscross or overlapping relation to each other. In some cases it may be desirable to provide a plurality of perforated pipes 24 near the bottom of the tank through which compressed air is forced to agitate the mix in the tank. The bottom of the tank has an outlet opening 25 connected to a pipe 26 through which the mix is conducted to the inlet of the forming machine. Pipe 26 may serve as a standpipe to provide a static head pressure on the mix 4 in the tank, the length of the pipe being varied to provide the desired pressure.

The fibers remain thoroughly and uniformly dispersed at random throughout the mix and are deposited on the screen 3 in crisscross or overlapping relation to each other so as to produce the layer or strip 6 in which the fibers are matted; and the excess liquid is forced from the layer by the compressed air that enters the upper portion of the tank through the pipe 11. Pressure rollers 28 may be used to smooth and compact the deposited layer.

The liquid to form the mix may be supplied to the tank 23 in any suitable manner, but as shown, a manifold pipe 29 is provided and has a plurality of branch outlets 30 spaced longitudinally thereof so that their lower ends may distllharge liquid from the pipe 29 continuously into the tan Other fibers may also be supplied to the mix in any suitable manner, for example, through a manifold pipe 31- having branch outlets 32 for discharging the fibers into the mix.

A modification of the invention is illustrated by FIG- URE'4. Here the glass fibers are pre-cut into short lengths 33 and deposited into a hopper 34 at the lower end of which is an outlet opening 35 beneath which is a guide plate or chute 36, the discharge end of which extends into a fiber distributing chamber 37. Beneath the discharge end of the plate 36 is a fiber distributor that is shown in the form of a shaft 38 rotatably mounting in the chamber walls and having a plurality of plates 39 projecting radially therefrom so that the fibers, as they drop by gravity from the plate 36, will fall onto the distributor and be whirled or thrown in various directions by the fiber distributor which is rotated by any suitable means in the direction of the arrow in FIGURE 4.

Preferably, the hopper and plate 36 will be constantly vibrated during operation of the machine, for example, by a well-known type of electrical vibrator 40 attached to the plate.

Preferably, the vanes or plates 39 of the fiber distributor will be formed of resilient material or covered by resilient material such as rubber so as to prevent any damage to the glass fibers.

In accordance with the invention, the dry fibers fall by gravity from the distributor 38, 39 freely through the atmosphere into the liquid 41 of the mix before the mix passes to the forming machine D. As shown, the lower end of the distributing chamber 37 is open and connected to a horizontal conduit 42 through which flows the liquid of the mix from any suitable supply. The horizontal conduit isconnected to the upper end of a standpipe 43, the lower end of which is connected to a tank 44 of the forming machine D which as shown is of the type described in my Patent No. 2,737,858. The standpipe 43 may be of any suitable length or height, for example, feet to feet, and the mix is deposited under the static head pressure from the lower open end of the tank D onto a forming screen 45 which continuously moves in its own plane upon any suitable support and by any suitable means such f. as shown in said Patent No. 2,737,858. The lower edges of the tank surrounding the open end thereof have attached thereto suitable sealing means 46, for example, such as the sealing means shown in said patent.

The fibers are deposited on the screen 45 and form a strip or mat E in which the fibers are uniformly distributed in overlapping, crisscrossed or interlaced relation to each other, and, of course, where other material such as synthetic resins are included in the mix, the fibers will be coated with such materials.

In some cases, it may be desirable to provide a water shower in the form of a perforated pipe 47 for directing a spray of water onto the surface of the mix to cause any floating fibers to sink into the mix.

An important feature of the invention is that it has been found that a large quantity of water in the mix tends to prevent the glass fibers from sticking together or gathering in bunches or clusters, and the rapid conduction of the mix to the forming screen through the straight standpipe without turbulence, causes the glass fibers to remain separated and uniformly dispersed in crisscross relation during the travel of the mix to the screen and throughout the mat or strip that is deposited on the screen.

Where large quantities of water are used in the mix, it may be desirable to form the strip or mat of material in a machine of the type shown in FIGURE 24 of my Patent No. 2,581,210 or by my pending application, Serial Number 740,377, filed June 6, 1958, so that the water that passes through the screen into the drum may be more v freely drained away from the drum than is possible by the drain pipe construction shown in FIGURE 1 of the present application.

It will be understood by those skilled in the art that after fiber strips of the nature described have been deposited on the forming element, the strips may be dried or otherwise treated, depending upon the compositions of the strips. For example, the strips may be heated or otherwise treated to cause proper bonding of resinous material with the fibers.

To avoid circumlocution, the term glass fibers is used in the specification and following claims to include all fibers that have the same general characteristics as glass fibers when mixed in a liquid with respect to the tendency to attract each other in side by side relation and to fiocculate.

It should be understood that while I have shown and described the now preferred method and types of apparatus in accordance with the invention, the steps of the method may be modified and changed and the method may be carried out by other types of apparatus within the spirit and scope of the invention.

What I claim is:

1. A method of forming on a screen a mat from a wet mix including a liquid and glass fibers suspended therein, said method including the steps of gravitationally dropping a multitude of short dry glass fibers haphazardly freely through the atmosphere into a body of liquid with the fibers pointing lengthwise in diiferent directions, conducting the resnltant mix with minimum turbulence to one side of said screen and causing the liquid from the mix to flow through the screen and deposit said fibers in crisscross relation to each other on said screen in matted condition.

2. A method as defined in claim 1 with the additional step of spraying liquid on the surface of said body of liquid to cause said fibers to sink into the body of liquid.

3. A method as defined in claim 1 with the additional step of injecting air jets into said body of liquid at the bottom thereof to gently agitate the fibers and prevent flocculation thereof.

4. A method of forming on a screen a mat from a wet mix including a liquid and glass fibers suspended therein, said method including the steps of gravitationally dropping a multitude of short dry glass fibers haphazardly freely through the atmosphere into a body of liquid at a point substantially higher than said screen With the fibers pointing lengthwise in different directions, causing the mix so formed to descend by gravity with minimum turbulence into contact with one side of said screen and causing the liquid from the mix to flow through the screen and deposit said fibers in crisscross relation to each other on said screen in matted condition.

5. A method of forming on a screen a mat from a wet mix including a liquid and glass fibers suspended therein, said method including the steps of gravitationally dropping a multitude of short dry glass fibers haphazardly freely through the atmosphere into a body of liquid at a point substantially higher than said screen with the fibers pointing lengthwise in diiferent directions, causing the mix so formed to descend by gravity through a substantially straight conduit in contact with one side of said screen and causing the liquid from the mix to flow through the screen and deposit said fibers in crisscross relation to each other on said screen in matted condition.

6. A method of forming on a screen a mat from a wet mix including a liquid and glass fibers suspended therein, said method including the steps of gravitationally dropping a multitude of short dry glass fibers haphazardly freely through the atmosphere into a body of liquid with the fibers pointing lengthwise in different directions, conducting the resultant mix to one side of said screen while maintaining said fibers haphazardly dispersed throughout the liquid and causing the liquid from the mix to fiow through the screen and deposit said fibers in crisscross relation to each other on said screen in matted condition.

7. Apparatus for forming a mat of material from a Wet mix including a liquid and glass fibers suspended therein, said apparatus including a container for liquid, means above the liquid level in said container for freely gravitationally dropping a multitude of glass fibers in separate dry condition through the atmosphere haphazardly and pointing in different directions into liquid in said container to form a wet mix, the container being of uniform cross-sectional area above the liquid level providing for unrestricted falling of the fibers from said means to the surface of the liquid a forming screen below said container and a substantially straight conduit extending downwardly from said container for conducting said mix from said container by gravity to said forming screen so that said fibers remain haphazardly dispersed throughout said mix.

References Cited in the file of this patent UNITED STATES PATENTS 1,708,724 Haug Apr. 9, 1929 1,799,685 Grninder Apr. 7, 1931 1,870,971 Sundstrom et al. Aug. 9, 1932 1,996,082 Powell Apr. 2, 1935 2,723,599 Simpson Nov. 15, 1955 2,762,081 Vivian Sept. 11, 1956 2,767,091 Hill et a1 Oct. 16, 1956 2,787,542 Labino Apr. 2, 1957

Claims (1)

1. A METHOD OF FORMING AN A SCREEN A MAT FROM A WET MIX INCLUDING A LIQUID AND GLASS FIBERS SUSPENDED THEREIN, SAID METHOD INCLUDING THE STEPS OF GRAVITATIONALLY DROPPING A MULTITUDE OF SHORT DRY GLASS FIBERS HAPHAZARDLY FREELY THROUGH THE ATMOSPHERE INTO A BODY OF LIQUID WITH THE FIBERS POINTING LENGTHWISE IN DIFFERENT DIRECTIONS, CONDUCTING THE RESULTANT MIX WITH MINIMUM TURBULENCE TO ONE SIDE OF SAID SCREEN AND CAUSING THE LIQUID FROM THE MIX TO FLOW THROUGH THE SCREEN AND DEPOSIT SAID FIBERS IN CRISSCROSS RELATION TO EACH OTHER ON SAID SCREEN IN MATTED CONDITION.

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