Gary D Mitchell

US Patent:

56821450, Oct 28, 1997

Filed:

Jun 30, 1995

Appl. No.:

8/497943

Inventors:

Gerald Patrick Sweetman - Colorado Springs CO
Gary Ross Mitchell - Boulder CO
Marcus Leroy Caldwell - Colorado Springs CO
William Louis Witt - Broomfield CO

Assignee:

Sensor Tech Incorporated - Sioux Falls SD

International Classification:

G08B 1710

US Classification:

340632

Abstract:

The present invention is a carbon monoxide or other toxic gas detector. The detector of the present invention detects the presence of carbon monoxide in an air sample by measuring the time required for the sensor circuitry to charge. Such a measurement technique eliminates the inaccuracies inherent in prior art detectors which measure the resistance of the sensor circuitry upon exposure to carbon monoxide. The detector of the present invention is controlled by a microprocessor which enables the detector to retain in memory air sample readings of carbon monoxide or other toxic gas. If the detector registers four consecutive readings which indicate the presence of carbon monoxide in an air sample in a concentration greater than or equal to about 100 ppm, then the alarm of the detector will be triggered, thereby alerting the user to a dangerous concentration of carbon monoxide gas in the air. Such a detection cycle enables the detector to detect not only high level, lethal concentrations of carbon monoxide in the air, but also, chronic, low level harmful concentrations of carbon monoxide in the air.

US Patent:

50124609, Apr 30, 1991

Filed:

May 31, 1985

Appl. No.:

6/739514

Inventors:

Steve S. Popovich - Colorado Springs CO
Russell A. Meyer - Colorado Springs CO
William J. Stanis - Colorado Springs CO
Christopher Miller - Manitou Springs CO
Gary R. Mitchell - Woodland Park CO

Assignee:

Information Storage, Inc. - Colorado Springs CO

International Classification:

G11B 700
G11B 7007

US Classification:

369 32

Abstract:

A method and apparatus for positioning and tracking a Random Access Memory (RAM) optical head over an information storage media having a plurality of tracks formed by optically readable deformations ("pits") in the media including, a central controller, a laser diode optical-system carrying head which is movable transversely of the tracks in incremental steps for coarse positioning of the head over a selected band of tracks and a servomechanism which positions the laser's objective lens over a specifically addressed track and maintains it there until another track is addressed. Also discussed is a unique method of generating a tracking error signal as an input to the servomechanism which includes the asynchronous detection of a sector mark and the generation of an independent clocking signal from the synchronous detection of off-track pairs of pits spaced uniformly between other data in the track to produce the tracking error signal.