Ford Global Technolgoies, LLC

Ford Motor Company Limited

Edward G Rychlick

Patrick Joseph Curran

David Chester Waskiewicz

Douglas Joseph Mancini

Bryce Andrew Schwager

Robert Joseph Pace

Michael A Panganis

Juliette J McCoy

A fuel canister (18) and fuel tank (14) are purged of any fuel vapors formed therein through a purge valve (22). A method (32) is used to purge the fuel canister (18) and fuel tank (14) in a manner which maintains the stoichiometric balance of fuel and air to be combusted by an internal combustion engine (12). Fuzzy logic is used to correlate the ratio of fuel to air (in mass per unit volume) to a duty cycle in which the purge valve (22) is opened. The fuzzy logic correlation includes the use of triangle functions having substantially similar period which are offset or skewed from each other by fifty percent. This allows each ratio value to be generated by two membership values which provides for a more accurate reading in a less complex manner.

Method for controlling rate of purging of evaporative fuel vapors

A method and system for determining a level of vapor generated by an evaporative system. The evaporative system is closed to atmosphere. An initial pressure in a fluid-filled tank is sensed and, after a predetermined amount of time, a second pressure in the tank is sensed. A pressure difference is determined based on the sensed initial pressure and the sensed second pressure. The level of vapor generated by the evaporative system is determined based on the pressure difference.

Method and system for controlling a flow of vapor in an evaporative

A method and system for monitoring an evaporative purge system for malfunctions and leaks. First, a plurality of predetermined entry conditions are checked for satisfaction. If the plurality of predetermined entry conditions have been met, a flow of vapor in the evaporative purge system is determined. The evaporative purge system is then sealed from atmosphere so as to pull a vacuum on the fuel tank. The vacuum is compared to a predetermined vacuum range. If the vacuum is within the predetermined vacuum range, the vacuum is allowed to stabilize to obtain a stabilized vacuum level. A decrease in the stabilized vacuum level is determined after a predetermined amount of time to obtain a vacuum bleed-up. A vacuum bleed-up acceptance threshold is then determined based on the determined flow of vapor and the vacuum bleed-up is then compared to the vacuum bleed-up acceptance threshold. If the vacuum bleed-up exceeds the vacuum bleed-up acceptance threshold, atmosphere is provided to the evaporative purge system until stabilization. The evaporative purge system is then sealed again to create a pressure build. The pressure build is compared to a pressure threshold. Finally, a malfunction signal is generated if the pressure build is less than the pressure threshold.

Method and system for monitoring an evaporative purge system

An evaporative purge flow monitoring system is provided for use in a motor vehicle having an internal combustion engine, a fuel tank, and an evaporation canister in communication with the fuel tank and the engine for trapping and subsequently reusing fuel vapor dispelled from the fuel tank. The evaporative purge flow monitoring system includes a vapor management valve interposed between the engine and the evaporation canister. An Electronic Engine Control (EEC) assembly is further provided in communication with the vapor management valve and the engine wherein the EEC assembly is provided with a test logic to determine satisfactory operation of the vapor management valve. The test logic determines whether the vapor management valve is defective based on either the presence of significant fuel vapor as determined by the test logic or a change in an engine performance parameter generated within the EEC assembly without requiring a separate sensor when the vapor management valve is temporarily closed.

Growing community of inventors

Dearborn, MI, United States of America

Edward G Rychlick