Hughes Aircraft Company

Raytheon Company

Kirk E Johnson

Raymond L Turner

David F Ciambrone

Edward Modzelewski

Hossien Ahmad

Larry L Kimmel

A system and method for vacuum bag assembly fabrication via the vacuum bag method which reduces the amount of trapped air. The inventive system includes a chamber adapted to contain a vacuum bag and first and second evacuating mechanisms. The first evacuating mechanism serves to evacuate the bag and vent to atmosphere. The second evacuating mechanism serves to evacuate and vent the chamber to atmosphere. Thus, generally, the inventive method includes the steps of placing a vacuum bag lay up in an air tight chamber; and evacuating the vacuum bag lay up and the air tight chamber at the same time. In practice, the assembly would consist of at least two components and a heat curable composition. The components can be parts to be bonded together or layers of cloth to be made into a laminate. In this case, the heat curable composition would be a catalyzed adhesive or resin.

System and method for vacuum bag fabrication

An improved process for the fusing a tin-lead solder mixture deposited to form a finished circuit on a printed circuit or wiring board. The method comprises the rapid or flash fusing of the circuit board having the tin-lead solder mixture deposited thereon by immersing into the vapor of an inert fluid having a boiling point just above the melting point of the solder alloy. Problems with 'weak knee' conditions are avoided by adjusting the heating time-at-temperature to that which allows the desired tin-lead solder alloy to form only as a thick 'mush' rather than as a molten fluid. By so doing, the solder alloy is formed without the necessary degree of fluidity that causes it to draw away from the edge or rim of plated holes in the board.

Vapor phase flash fusing of printed wiring boards

A non-toxic, non-corrosive water-soluble soldering paste comprises at least about 80 wt % of particulate solder and the balance a thixotropic flux base. The flux base has a viscosity of at least about 200,000 cp and comprises (a) a botanical oil, (b) an aqueous emulsion of a thickening agent, such as corn starch or an ethoxylated linear alcohol in water, and (c) an organic acid having at least two carboxylic acid groups, such as citric acid. The paste of the invention produces solder joints of high metallic luster and excellent quality. Clean-up of paste residues is ac complished using only water.

Growing community of inventors

Diamond Bar, CA, United States of America

Kirk E Johnson