Citations
- 323 F.2d 1016
Full opinion text
RICH, Judge.
This appeal is from the Patent Office Board of Appeals affirming the rejection -of claims 9, 10, and 12-16 of application Serial No. 440,369, filed June 30, 1954, ■entitled “Hollow Glass Fiber Shaft.”
The invention relates to hollow fiberglass rods of uniform outside diameter, ■particularly suitable for use as archery .arrow shafts. The claims on appeal are ■directed to both the rods and the method •of making them.
The novelty of appellant’s invention resides in using a paper tube as the core ■of the rod. The paper tube is cylindrical and consists of helical windings of paper tape, like an ordinary soda straw. The Ihollow fiber-glass rod is made by feeding ■strands of glass fibers coated with thermosetting resin longitudinally into .a rigid mold in surrounding relation to the paper tube. The tube remains inside the fibers and serves as a permanent mandrel supporting the fibers. While in the mold the rod is heated to cure the Tesin, thereby forming a permanently ^hardened mass. Because the mold is rigid, the finished rod is straight and has -a uniform outside diameter. Appellant -does not allege novelty in the process except for the use therein of the paper •core.
In describing his invention, appellant’s specification states:
“ * * * it is an object of the invention to provide a linear shaft consisting of a hollow core of soft, fibrous material of low rigidity and an outer tube fabricated of longitudinally-extending glass fibers held together by a bonding agent, said core having sufficient stiffness to constitute a former for the surrounding glass fibers in the assembling of the shaft.
“Another object is to provide a core which is soft and resilient to permit the resin employed to shrink during the curing thereof without the formation of cracks as is the ease many times when a hollow shaft is formed on a metal mandrel. ******
“ * * * the hollow paper core serves as a former during the assembly of the shaft but otherwise has a very little effect on the mechanical characteristics of the shaft, which characteristics are determined exclusively by the bonded glass fibers.” [Emphasis ours.]
Thus, the paper core is strong enough to circumferentially support the glass fibers during molding but will not distort the finished rod due to expansion and contraction c