초록 ▼

A control system for a dual fuel engine using primary diesel fuel and supplemental gas fuel such as propane or natural gas includes a control valve that controls supplemental fuel mixing with intake air by using an air deflectable member that controls the position of a valve controlling the admissio

A control system for a dual fuel engine using primary diesel fuel and supplemental gas fuel such as propane or natural gas includes a control valve that controls supplemental fuel mixing with intake air by using an air deflectable member that controls the position of a valve controlling the admission of supplemental gas to the engine intake airstream. A damper is provided on the air flow responsive member to improve valve operation and a lost motion connection is provided between the air flow responsive member and the control valve element to permit independent movement of the elements. Normal flow of supplemental fuel to the control valve is further modulated in response to certain engine operating conditions using an engine condition comparator that generates a control signal used by the supplemental fuel pressure regulator to further modulate the supply of supplemental fuel to the intake airstream. The system includes a supplemental fuel shut-off system that restores full primary diesel fuel flow to the engine when the supply of supplemental fuel approaches depletion.

대표청구항 ▼

A supplemental gas fuel control system for a dual fuel supply system for an internal combustion engine having an air intake duct for conveying an intake airstream to the engine, an exhaust duct, and using a primary liquid fuel, the control system comprising a pressure regulator including a movable r

A supplemental gas fuel control system for a dual fuel supply system for an internal combustion engine having an air intake duct for conveying an intake airstream to the engine, an exhaust duct, and using a primary liquid fuel, the control system comprising a pressure regulator including a movable regulator valve positionable for controlling flow of supplemental gas fuel from a high pressure source to the intake airstream of the engine within said air intake duct, the position of the regulator valve normally governed by engine inlet airstream flow conditions, said flow conditions communicated normally to the pressure regulator by using an air intake duct suction pressure signal acting on a controller for the regulator valve; a condition comparator means; means for sensing exhaust gas rate of flow of the engine and communicating an exhaust flow signal corresponding to same to the condition comparator means; means for sensing a reference pressure in a reference pressure zone in the engine air intake duct and communicating a reference signal corresponding to same to the condition comparator means; means for sensing intake air rate of flow at an intake duct zone downstream of a source of said reference signal, and communicating an intake air flow signal corresponding to same to said condition comparator means; said condition comparator means including means for proportioning said exhaust flow, reference and intake air flow signals to produce a net control signal; means for communicating said net control signal to said supplemental fuel pressure regulator; said pressure regulator including means for modulating the position of said regulator valve in response to both said suction pressure signal and said net control signal.