US 4,294,655 AGranted

Method and apparatus for forming fiberglass mats

AssigneeConsolidated Fiberglass Products Company

InventorJohn R. Pfeffer

Life of this patent

Estimating the term…

Loading patent…

Abstract

A machine and method of forming fiberglass mats. Chopped glass fibers are mixed with water in a slurry and a movable screen is passed, generally upwardly, through a slurry. As the screen is moved, its surface is uniformly coated with the glass fibers in a uniformly increasing depth, dependent upon the length of travel of the screen through the slurry. Longitudinally oriented and randomly oriented continuous strands are projected onto the fibers captured on the screen at different locations in order to provide the resultant mat with tear strength in all directions. The screen passes over a vacuum for removal of most of the water from the workpiece; subsequently, a binder is added to the workpiece and the continuous mat is passed through an oven for curing of the binder. The mat is then wound upon a spool for later transport to a location in which the mat can be processed into a final product.

Claims14

Dependent claims

The method of making a wet process fiber mat comprising the steps of:

a. forming an aqueous body of chopped fiber slurry;
b. moving an endless screen upwardly through said slurry from an entrance position spaced substantially below said slurry surface and at a predetermined rate of movement to an exit position at the surface of said slurry;
c. applying suction to the lower surface of said screen, in a zone through which said screen moves in order to draw water of said slurry through said screen thereby;
d. collecting a first layer of chopped fibers on the surface of the screen with increasing thickness as the distance traveled by the screen through the slurry increases;
e. positioning a first reinforcement strand projecting means beneath the surface of the slurry;
f. projecting a plurality of first continuous reinforcement strands through said first strand projecting means below the slurry surface by propelling said first strands at approximately the same velocity as said screen onto said first chopped fiber layer at a first predetermined location intermediate the ends of the screen thereby depositing said first reinforcement strands in a longitudinally oriented configuration and in a first substantially horizontal plane within the resultant mat;
g. collecting a second layer of chopped fibers on top of said first layer and said first reinforcement strands with increasing thickness as the distance traveled by the screen through the slurry increases;
h. positioning a second reinforcement strand projecting means above the surface of said slurry at a location between the first projecting means and the exit position;
i. projecting a plurality of second continuous reinforcement strands onto the surface of said slurry by projecting said second strands from said second strand projecting means from above the slurry surface onto that slurry surface near said exit position at a velocity greater than the velocity of said screen such that the second strands assume a randomly oriented interengaged configuration upon entering said slurry;
j. allowing said random interengaged strands to migrate in an unconstrained manner from the slurry surface through the slurry and onto said second chopped fiber layer captured by the screen at a second predetermined location intermediate the ends of said screen thereby depositing said second reinforcement strands in a substantially horizontal plane within the resultant mat so that both random and longitudinal reinforcement strands will be present in the resultant mat;
k. continuing the movement of the screen past the point of randomly oriented strand installation to cover said strands with a third uniform layer of chopped fibers;
and
l. moving the screen out of the slurry, thus withdrawing the wet mat from the slurry.

10 more elements

The method of making a non-woven fiber mat comprising the steps of:

a. mixing chopped glass fibers with water to form a slurry;
b. moving an endless screen within said slurry in a position spaced a distance substantially below said slurry surface and at a predetermined rate of of movement;
c. applying suction to the lower surface of said screen, in a zone through which said screen moves in order to draw water of said slurry through said screen thereby collecting a first layer of said fibers on the surface thereof with increasing thickness as the distance traveled by the screen through the slurry increases;
d. projecting a plurality of continuous reinforcement strands through elongated tubes extending below the slurry surface by employing a fluid propellant to propel said strands onto said first layer of chopped fibers at a predetermined location intermediate the ends of the screen travel through the slurry;
e. controlling the velocity at which said strands enter said slurry by drawing said strands through braking means such that said strands' velocity is substantially the same as the velocity of said screen;
f. controlling the pressure of said propellant in said tubes and thereby controlling said strands' velocity such that said strands assume a generally longitudinal configuration within a predetermined single horizontal plane within the resultant mat;
g. continuing the movement of the screen past the point of longitudinal strand installation to cover said strands with a uniform second layer of chopped fibers;
h. projecting a plurality of continuous reinforcement strands onto the surface of said slurry by employing a fluid propellant to project said strands through elongated tubes positioned above the slurry surface at a velocity such that the strands assume a randomly oriented interengaged configuration upon entering said slurry;
i. allowing said randomly interengaged strands to be carried through the slurry and onto the second chopped fiber layer captured by the screen at a predetermined location intermediate the ends of said screen and thereby being deposited in a single horizontal plane within the forming mat;
j. continuing the movement of the screen past the point of randomly oriented strand installation to cover the randomly oriented interengaged strands with a uniform third layer of chopped fibers;
and
k. moving the screen out of the slurry thus withdrawing the mat from the slurry.

9 more elements

Apparatus for forming a non-woven mat including means for forming a slurry of substantially uniformly dispersed glass fiber means for separating the fibers from the slurry in a uniformly increasing thickness as said separating means is moved through the slurry, the thickness being dependent upon the distance and the rate of travel of said separating means through said slurry means for moving said separating means through and out of the slurry in a gradually rising movement;

the improvement comprising:
a. strand projection means positioned above the surface of said slurry for directing fluid propellant therethrough to project a plurality of continuous fiber strands onto the surface of said slurry at a predetermined location intermediate the travel extremities of said separating means through the slurry such that said strands will be carried through the slurry and onto said separating means;
b. means for controlling the fluid pressure of said propellant in such strand projection means thereby controlling the velocity at which said strands are projected onto the slurry surface, to project said strands onto said slurry surface at a velocity greater than the speed of said separating means such that said strands upon being carried through the slurry and deposited on said separating means assume a randomly oriented interengaged configuration in a predetermined single substantially horizontal plane within the resultant mat;
c. strand projection means positioned beneath the surface of said slurry for directing fluid propellant therethrough to project a plurality of continuous fiber strands onto the surface of the separated fibers at a predetermined location intermediate the travel extremities of said separating means;
and
d. means for controlling the fluid pressure of the last mentioned propellant in such strand projection means thereby controlling the velocity at which said strands are projected into the slurry to project said last mentioned strands into said slurry at a velocity approximately equal to the velocity of said separating means such that said last mentioned strands are deposited on said separating means in a longitudinally arranged configuration in a predetermined single substantially horizontal plane within the resultant mat.

3 more elements

Apparatus for forming a non-woven mat including means for forming a slurry of substantially uniformly dispersed glass fiber means for separating the fibers from the slurry in a uniformly increasing thickness as said spearating means is moved through the slurry, the thickness being dependent upon the distance and the rate of travel of said separating means through said slurry means for moving said separating means through and out of the slurry in a gradually rising movement;

the improvement comprising:
a. strand projection means for directing fluid propellant therethrough to project a plurality of continuous reinforcing strands against said chopped fibers deposited on said separating means at an essentially horizontal planar location within the slurry at a predetermined location intermediate the travel extremities of said separating means through the slurry, said projection means extending downwardly through said slurry to a position near the surface of said separating means, to project said strands toward said separating means;
b. means for controlling the velocity at which said strands enter said projection means such that said strands velocity is substantially the same as the velocity of said separating means;
c. means for controlling the fluid pressure of said propellant in said strand projection means thereby further controlling the velocity of said strands such that said strands can be made to assume a generally longitudinal configuration within a predetermined single essentially horizontal plane in the resultant mat;
d. additional strand projection means positioned above the surface of said slurry for directing fluid propellant therethrough to project a plurality of continuous reinforcing strands onto the surface of said slurry at a predetermined location intermediate the travel extremities of said separating means through the slurry;
e. means for controlling the fluid pressure of said propellant in said additional strand projection means thereby controlling the velocity of said strands to project strands onto said slurry surface at a velocity greater than the speed of said separating means such that said last mentioned strands upon being deposited on said separating means assume a randomly oriented interengaged configuration in a single essentially horizontal plane within the resultant mat.

3 more elements

Dependencies are inferred from the claim text.

Facts

Application: 06/097,776Filed 27 Nov 1979 · continuation
Priority: 15 Mar 1978
Granted: 13 Oct 1981
Term ends: Not estimatedThe source records don’t support an estimate.

Classification7 codes

D21H 15/06
Characterised by configuration: long fibres, i.e. fibres exceeding the upper length limit of conventional paper-making fibres; Filaments
D21F 9/00
Complete machines for making continuous webs of paper
D21H 5/1245
Characterised by the use of special fibrous materials: of long or continuous filaments
D21H 13/40
Siliceous: vitreous, e.g. mineral wool, glass fibres