Composite Structural Members.

Reference: International Patent WO 01/64570 A1, 7 September 2001.

This patent claims "a method for making a fiber reinforced resin composite" structure by filament winding around structural inserts.

This invention provides reduction of weight of mechanical systems by use of lightweight fiber reinforced composite material and reducing use of heavy metal.

Composite housing increases corrosion resistance by covering internal structural metal components.

By this patent, the filament winding material goes through a container with resin before being wound around the structural inserts.

Different shapes can be produced. The shape is determined by the location of the structural inserts. When the resin cures the inserts can stay bonded into the composite member or they can be removed.

Multiple layers of filament winding material provide required strength of the part. The structural inserts must be some round outside but this process does not limit the internal shape of the inserts. The internal area of the structural inserts can be machined to any form before or after curing of resin.

We have learned from this patent that the forming channels and forms can be used for holding the filament winding material wile the resin cures. Then the channels and form are removed.

We indeed agree with the statement of this patent that the invention allows producing different shapes of the mechanical components. The shape is determined by the location of the turning points.

United States Patent 5,875,693 is the most relevant to this invention. Steel ring gear is used as a structural insert, but the oriented filament winding material is mixed with randomly oriented fibers.

Using a metal ring gear as a structural insert proved to be reliable and successful on Snap-On Tools product, which is used for turning mechanical elements by applying substantial torque.

While US Patent 5,875,693 limits the use of composite housing only for a ring gear, the international patent WO 01/64570 A1 is much broader. It is absolutely obvious that the structural inserts do not have to be the ring gears like on composite product of Snap-On Tools, Inc.