James B Pritchard

55628834, Oct 8, 1996

May 5, 1995

8/436002

Wayne C. Salisbury - Middleton NH
James R. Pritchard - Somersworth NH
William M. Humphrey - Dover NH
Michael J. Provencher - Barrington NH

Davidson Textron Inc. - Dover NH

B01F 502
B01F 504

422133

A solvent flush reaction injection molding mixhead has a mixing chamber with a solvent inlet port in one end and a chemical outlet port in an opposite end. A pair of hydraulically operated chemical injectors are connected to the mixing chamber between the solvent inlet port and chemical outlet port to inject liquid reaction molding chemicals at high pressure through injector ports into the mixing chamber. The mixed chemicals are delivered through the chemical outlet port to a spray wand on the mixhead for application to a mold surface or an object requiring a foam coating. A flush valve is associated with the solvent inlet port and is moveable from a closed position to block the solvent inlet port while the chemicals are injected into the mixing chamber, and an open position where liquid solvent under a high pressure is supplied through turbulator ports into the mixing chamber to clean and flush any remaining mixed chemicals from the flush valve, the mixing chamber including the chemical injector ports, and the spray wand.