William Jeremy Higdon

US Patent:

55781578, Nov 26, 1996

Filed:

Sep 28, 1994

Appl. No.:

8/314479

Inventors:

William R. Higdon - Pleasanton CA

Assignee:

Microsensor Technology, Inc. - Fremont CA

International Classification:

B29C 6502
B29C 6554

US Classification:

156278

Abstract:

A detachable column cartridge for a gas chromatograph is disclosed. The cartridge column contains analytical and reference columns, a heater and a thermocouple, and connects via detachable connectors to a base unit containing an injector, a detector and other components normally found in gas chromatographs. The cartridge arrangement permits a substitute column to be connected to the base unit easily, in the field, when different gases are to be separated and analyzed. Also included are specific connectors for detachably connecting the columns with capillary tubes in the base unit of the gas chromatograph.

US Patent:

59642394, Oct 12, 1999

Filed:

May 23, 1996

Appl. No.:

8/652878

Inventors:

Alan D. Loux - Livermore CA
William R. Higdon - Pleasanton CA
Timothy G. Slater - San Francisco CA

Assignee:

Hewlett-Packard Company - Palo Alto CA

International Classification:

F16K 4300
F16K 2700

US Classification:

137 15

Abstract:

A housing for a (silicon) micromachined body (for instance an injector valve system, a detector or a stream selector for a gas chromatograph instrument) is field assemblable and disassemblable and mechanically self-aligning so that the micromachined body may be replaced in the field without tools and without adhesives or permanent bonding. The housing includes a top plate and a bottom plate spaced apart by two side rails and accommodating the micromachined body. The various tubes carrying fluids and pneumatic pressure to and from the micromachined body are attached to the housing by adhesives or brazing or by detachable screw-type fittings. The housing is held in alignment by alignment pins passing through it and is clamped together by a spring clamp which also clamps the housing to a printed circuit board and associated planar heater element. In addition to easy field assembly, this assembly allows manufacturing without precision alignment tools, adhesives, or welding.

US Patent:

61020680, Aug 15, 2000

Filed:

Sep 23, 1997

Appl. No.:

8/936044

Inventors:

William R. Higdon - Pleasanton CA
Alan D. Loux - Livermore CA

Assignee:

Hewlett-Packard Company - Palo Alto CA

International Classification:

F16K 1100

US Classification:

137341

Abstract:

A selector valve assembly has reduced size, reduced cost, and increased repeatability with improved reliability and reduced maintenance expense due to use of a silicon micromachined valve body held in a releasable housing which in turn is mounted on a manifold plate to which are attached inlet and outlet fluid carrying tubing. The manifold plate includes two metal plates bonded together by an intervening polymer film and defining thread female connection inlets for tube fittings. The micromachined valve body is connected to a pilot valve assembly providing pneumatic operation of the micro-valves in the micromachined valve body. Also, a heater is mounted on the manifold plate to maintain temperature. The micromachined valve body is held on the manifold plate by a releasable spring-loaded assembly allowing quickly replacement of the micro-valve body in case of its failure.

US Patent:

56017855, Feb 11, 1997

Filed:

Mar 28, 1994

Appl. No.:

8/218605

Inventors:

William R. Higdon - Pleasanton CA

Assignee:

Microsensor Technology, Inc. - Fremont CA

International Classification:

B01L 1100

US Classification:

422103

Abstract:

A detachable column cartridge for a gas chromatograph is disclosed. The cartridge column contains analytical and reference columns, a heater and a thermocouple, and connects via detachable connectors to a base unit containing an injector, a detector and other components normally found in gas chromatographs. The cartridge arrangement permits a substitute column to be connected to the base unit easily, in the field, when different gases are to be separated and analyzed. Also included are specific connectors for detachably connecting the columns with capillary tubes in the base unit of the gas chromatograph.

US Patent:

52366685, Aug 17, 1993

Filed:

Dec 23, 1991

Appl. No.:

7/812532

Inventors:

William R. Higdon - Pleasanton CA

International Classification:

G01N 3054

US Classification:

422 89

Abstract:

A detachable column cartridge for a gas chromatograph is disclosed. The cartridge column contains analytical and reference columns, a heater and a thermocouple, and connects via detachable connectors to a base unit containing an injector, a detector and other components normally found in gas chromatographs. The cartridge arrangement permits a substitute column to be connected to the base unit easily, in the field, when different gases are to be separated and analyzed.

US Patent:

52982254, Mar 29, 1994

Filed:

Jul 30, 1993

Appl. No.:

8/100022

Inventors:

William R. Higdon - Pleasanton CA

Assignee:

Microsensor Technology, Inc. - Fremont CA

International Classification:

G01N 3054

US Classification:

422 89

Abstract:

A detachable column cartridge for a gas chromatograph is disclosed. The cartridge column contains analytical and reference columns, a heater and a thermocouple, and connects via detachable connectors to a base unit containing an injector, a detector and other components normally found in gas chromatographs. The cartridge arrangement permits a substitute column to be connected to the base unit easily, in the field, when different gases are to be separated and analyzed.