Abstract: A blending apparatus for continuously and accurately blending a plurality of diverse, normally gaseous or volatile liquid components, preferably two or three, at low pressures. In a preferred embodiment, the apparatus blends a first stream of volatile liquid component, preferably carbon dioxide with a liquid stream of any suitable hydrocarbon (including halogenated hydrocarbons) blowing agent in accordance with any predetermined ratio desired by those skilled in the art before introducing the blend into a suitable extrusion process for preparation of polymeric foams and the like. The apparatus combines the liquid components at a pressure substantially lower than the elevated pressure required during the extrusion process.

Abstract: A coupling between a direct drive valve motor and a spool for converting rotary-to-linear motion. A bushing is coupled to the spool and defines an opening therein. An end of a shaft carried by the rotor of the motor is received within an opening in the busing. The bushing is outwardly expandable upon the receipt of the end of the shaft to couple the shaft to the spool with minimal frictional forces and near zero backlash.