Donald C Curtis

US Patent:

H172, Dec 2, 1986

Filed:

Mar 26, 1986

Appl. No.:

6/845668

Inventors:

William J. Pribyl - Baltimore MD
Donald L. Curtis - Edgewood MD

Assignee:

The United States of America as represented by the Secretary of the Army - Washington DC

International Classification:

C09K 330
C06D 300
F41H 906

US Classification:

252305

Abstract:

An air purge system device for use with nozzle tubes carrying fuel oil to a iesel engine exhaust system for vaporization of the fuel oil. Provided is at least one nozzle tube for carrying fuel oil to the diesel engine exhaust system and an electrically controlled solenoid valve for controlling flow of fuel from a fuel supply source for the diesel engine to the nozzle tubes. An air purge line is provided for forcing air into the tube from the diesel engine air box. A one-way check valve is provided to permit air flow from the air purge line to the tube and prevent fuel flow from the fuel valve to the air purge line. The method described prevents coke build-up in nozzle tubes carrying the fuel oil, which fuel is vaporized during operation of a fuel supply valve. The method contemplates supplying air under pressure from a positive pressure air source to an air purge line positioned to force air into the nozzle tubes when fuel supply valve is closed and regulating flow in the air purge line by a one-way check valve on the purge line which permits air flow towards the tube and prevents fuel flow in the air purge line. Operation of the device in engine compartments having an operating temperature above the vaporization temperature of fuel oil purges the nozzle tubes and cools the interior of the nozzle tubes to prevent coking by volatilization of residual fuel oil in the system after the supply has been turned off.