PAUL A. JOHNSON, MD
Osteopathic Medicine at State Farm Dr, Cotati, CA

5487313, Jan 30, 1996

Nov 30, 1993

8/158978

Paul H. Johnson - Oakland CA

Microsensor Technology, Inc. - Fremont CA

G01N 3000, G01N 100

7386371

An automated micro-valve assembly injects a fixed fluid volume fluid into a destination stream. The fluid to be injected (inject fluid) is conducted into a chamber. Flow of inject fluid out of the chamber is prevented by sealing the ends of the chamber using valves or by application of pressure. A fixed volume of inject fluid is injected into the destination stream by pressurizing the inject fluid in the chamber and opening an inject valve which connects the chamber to the destination stream. The pressurization of the inject fluid in the chamber above the destination stream pressure is effected by a T-valve which controls the flow of a purge fluid into the chamber. The purge fluid emitted by the T-valve flows toward the inject valve, forming a fluid-lock which establishes the fixed-volume to be injected. During the injection, the inject fluid is driven by the purge fluid pressure to flow through the inject valve into a destination passage which communicates with the destination stream. The inject fluid in the section of chamber between the T-valve orifice and the inject valve orifice is injected, as the purge fluid emitted at the T-valve displaces the inject fluid from that section of the chamber.

5544276, Aug 6, 1996

Nov 30, 1993

8/159185

Alan D. Loux - Livermore CA
R. Sjhon Minners - San Jose CA
Paul H. Johnson - Oakland CA

Microsensors Technology, Inc. - Fremont CA

H05B 102, G01N 3108, F24H 110

392480

A miniature gas chromatograph with thermostatically-controlled heating of its component parts which contact and conduct the sample to the analytical column. The microvalve assembly of the gas chromatograph is heated by passing a thermostatically-controlled electrical current through a metallic conductor formed on a surface of the microvalve assembly. The tubing which conducts sample from the gas chromatograph sample inlet to the microvalve assembly is heated by passing a thermostatically-controlled electrical current directly through the tubing or through a metal layer formed around the tubing. The sample inlet fitting is heated by a wire heater element wrapped around it. Each heater has an associated temperature sensor for controlling the amount of heating to maintain a predetermined temperature.