Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
270 words
THE METHOD OF FORMING A HOLLOW STRUCTURE HAVING A SHAPE WITH A NONCIRCULAR CROSS SECTION WHICH COMPRISES: PREPARING A WINDING MANDREL BY MOUNTING CIRCULAR END PLATES ON SHAFT MEANS, SECURING FLEXIBLE SHEET MATERIAL ABOUT THE PERIPHERY OF SAID END PLATES AND EXTENDING THEREBETWEEN, FORMING A SEALED ENVELOPE WITHIN SAID MANDREL AND ESTABLISHING A POSITIVE DIFFERENTIAL FLUID PRESSURE THEREIN TO DEFINE A MANDREL HAVING A CIRCULAR CROSS SECTION AND AN ARCUATE EXTERIOR SURFACE, PREPARING A CONTINUOUS FILAMENT WRAPPING ABOUT SAID WINDING MANDREL BY ROTATING SAID MANDREL SAID WINDING FILAMENTS OF FIBROUS REINFORCEMENT MTERIAL IN A HELICAL PATH ABOUT SAID MANDREL BY GUIDING SAID FILAMENTS IN A MANDREL END-TO-END TRAVERSING PATH TO APPLY A PLURALITY OF LAYERS OF CIRCUMFERENTIALLY AND HELICALLY WOUND FILAMENTS THEREON WITH A HELIX ANGLE FROM 0* TO ABOUT 90*, CONTROLLING THE POSITIVE DIFFERENTIAL FLUID PRESSURE IN SAID SEALED ENVELOPE TO MAINTAIN THE ARCUATE EXTERIOR SURFACE OF SAID MANDREL DURING SAID WINDING, EMBEDDING SAID LAYERS OF WOUND FILAMENTS IN A BONDING RESIN, RELIEVING SAID POSITIVE DIFFERENTIAL PRESSURE TO COLLAPSE SAID MANDREL AND RELEASE SAID WRAPPING AS A FLEXIBLE SHEATHING OF CONTINUOUS FILAMENT WRAPPING, PLACING SAID FLEXIBLE SHEATHING OF CONTINUOUS FILAMENT WRAPPING IN A MOLD CAVITY BEARING DIE FACES WITH AN INTAGLIO FORM OF THE EXTERIOR SURFACE OF SAID HOLLOW STRUCTURE OF NONCIRCULAR CROSS SECTION, ESTABLISHING A POSITIVE DIFFERENTIAL PRESSURE IN THE INTERIOR OF SAID FLEXIBLE SHEATHING OF CONTINUOUS FILAMENT WRAPPING TO EXPANDING SAID SHEATHING INTO SURFACE-CONFORMING CONTACT WITH SAID DIE FACES, CURING SAID BONDING RESIN TO BOND SAID SHEATHING INTO SAID HOLLOW STRUCTURE, TRIMMING SAID END PLATES AND SAID FLEXIBLE SHEATHING, AND REMOVING SAID HOLLOW SHAPE FROM SAID MOLD.
Claim 2
Independent Claim
270 words
THE METHOD OF FORMING A HOLLOW STRUCTURE HAVING A SHAPE WITH A NONCIRCULAR CROSS SECTION WHICH COMPRISES: PREPARING A WINDING MANDREL BY MOUNTING CIRCULAR END PLATES ON SHAFT MEANS, SECURING FLEXIBLE SHEET MATERIAL ABOUT THE PERIPHERY OF SAID END PLATES AND EXTENDING THEREBETWEEN, FORMING A SEALED ENVELOPE WITHIN SAID MANDREL AND ESTABLISHING A POSITIVE DIFFERENTIAL FLUID PRESSURE THEREIN TO DEFINE A MANDREL HAVING A CIRCULAR CROSS SECTION AND AN ARCUATE EXTERIOR SURFACE, PREPARING A CONTINUOUS FILAMENT WRAPPING ABOUT SAID WINDING MANDREL BY ROTATING SAID MANDREL SAID WINDING FILAMENTS OF FIBROUS REINFORCEMENT MTERIAL IN A HELICAL PATH ABOUT SAID MANDREL BY GUIDING SAID FILAMENTS IN A MANDREL END-TO-END TRAVERSING PATH TO APPLY A PLURALITY OF LAYERS OF CIRCUMFERENTIALLY AND HELICALLY WOUND FILAMENTS THEREON WITH A HELIX ANGLE FROM 0* TO ABOUT 90*, CONTROLLING THE POSITIVE DIFFERENTIAL FLUID PRESSURE IN SAID SEALED ENVELOPE TO MAINTAIN THE ARCUATE EXTERIOR SURFACE OF SAID MANDREL DURING SAID WINDING, EMBEDDING SAID LAYERS OF WOUND FILAMENTS IN A BONDING RESIN, RELIEVING SAID POSITIVE DIFFERENTIAL PRESSURE TO COLLAPSE SAID MANDREL AND RELEASE SAID WRAPPING AS A FLEXIBLE SHEATHING OF CONTINUOUS FILAMENT WRAPPING, PLACING SAID FLEXIBLE SHEATHING OF CONTINUOUS FILAMENT WRAPPING IN A MOLD CAVITY BEARING DIE FACES WITH AN INTAGLIO FORM OF THE EXTERIOR SURFACE OF SAID HOLLOW STRUCTURE OF NONCIRCULAR CROSS SECTION, ESTABLISHING A POSITIVE DIFFERENTIAL PRESSURE IN THE INTERIOR OF SAID FLEXIBLE SHEATHING OF CONTINUOUS FILAMENT WRAPPING TO EXPANDING SAID SHEATHING INTO SURFACE-CONFORMING CONTACT WITH SAID DIE FACES, CURING SAID BONDING RESIN TO BOND SAID SHEATHING INTO SAID HOLLOW STRUCTURE, TRIMMING SAID END PLATES AND SAID FLEXIBLE SHEATHING, AND REMOVING SAID HOLLOW SHAPE FROM SAID MOLD.
Claim 3
Dependent Claim
16 words
The method of claim 1 wherein said filaments comprise wound and twisted filaments of glass fibers.
Claim 4
Dependent Claim
14 words
The method of claim 1 wherein said filaments comprise twisted strands of carbon fibers.
Claim 5
Dependent Claim
13 words
The method of claim 1 wherein said bonding resin is a polyester resin.
Claim 6
Dependent Claim
13 words
The method of claim 1 wherein said bonding resin is an epoxide resin.
Claim 7
Dependent Claim
35 words
The method of claim 4 wherein said resin is cured by heating said sheathing in said mold cavity to a temperature from 75* to 400* F. for a period of 10 minutes to 7 days.
Claim 8
Dependent Claim
34 words
The method of claim 5 wherein said resin is cured by heating said sheathing in said mold cavity to a temperature from 100* to 225* F. for a period of 60 to 300 minutes.
Claim 9
Dependent Claim
21 words
The method of claim 1 wherein said filaments are applied to said mandrel at a helix angle from 5* to 90*.
Claim 10
Dependent Claim
29 words
The method of claim 1 wherein said bonding resin is applied to said filaments by coating said resiN on said filaments as the filaments are wound onto said mandrel.
Claim 11
Dependent Claim
24 words
The method of claim 1 wherein said filaments are wound on said mandrel at a tension of from 0.1 to 10 pounds per filament.
Claim 12
Dependent Claim
36 words
The method of claim 1 including the steps of placing a container of an elastomeric material within said mandrel to form said sealed envelope and removing said container from said hollow structure after said curing step.
Claim 13
Dependent Claim
24 words
The method of claim 1 wherein said step of trimming said end plates from said continuous filament wrapping is performed before said curing step.
Claim 14
Dependent Claim
32 words
The method of claim 1 wherein said flexible sheathing is sealed to said end plates to define said envelope and said end plates are trimmed from said sheathing after said curing step.
Claim 15
Dependent Claim
18 words
The method of claim 1 wherein said mold defines a hollow structure with an air foil cross section.
Claim 16
Dependent Claim
65 words
The method of claim 1 wherein said mold is formed by joining mold sections bearing die faces that mate together to form a mold cavity of an intaglio pattern of the desired article and wherein said sheathing of continuous filament wrapping is oversized for said cavity and the oversized portion thereof is looped outside said mold cavity along a mating edge of said mold sections.