Thomas J Murdock

US Patent:

7068362, Jun 27, 2006

Filed:

Jan 22, 2003

Appl. No.:

10/348890

Inventors:

Thomas M. Murdock - Eldersburg MD, US
Kirk S. Decker - Catonsville MD, US
James T. Velky - Baltimore MD, US
Karen D. Rennich - Elkridge MD, US

Assignee:

The Johns Hopkins University - Baltimore MD

International Classification:

G01J 1/44
G01N 21/00

US Classification:

356226, 356432, 356218

Abstract:

The present invention provides apparatus for a beam transmissometer. In an embodiment, the beam transmissometer includes a LED signal source, collimating apparatus, a retroreflector that directs the projected beam, imaging apparatus that directs the beam onto a detector that converts the projected beam into an electrical signal, and signal processing circuitry that enhances the reception of the optical beam. The LED signal source is modulated in a pulsed fashion so that the effects of beam reflection are ameliorated. Signal processing circuitry amplifies, filters, and synchronizes to the electrical signal. A calculating unit uses the processed signal to determine a beam attenuation coefficient, which is indicative of the visibility of a medium in which the transmissometer is immersed. A method is also provided for aligning optics of a beam transmissometer. The method determines an offset and a rotation of a retroreflector housing that causes an optical beam to be centered.

US Patent:

50586939, Oct 22, 1991

Filed:

May 7, 1990

Appl. No.:

7/520028

Inventors:

Thomas G. Murdock - Northville MI
Steven G. Mixter - Howell MI

Assignee:

Industrial Strainer Co. - Plymouth MI

International Classification:

B60K 1500

US Classification:

180 694

Abstract:

A fuel vapor recovery system for a vehicle includes a charcoal canister connected to the fuel tank for collecting fuel vapors from the tank as it is being refilled. After the tank is filled and the engine started, the charcoal canister is purged of accumulated vapors. As the canister is being purged, it receives atmospheric air to fill the purged volume. A filter is remotely connected by a hose to the air inlet of the canister. The filter assembly removes dirt, dust, and water from the incoming air.