초록 ▼

In a turbocharged internal combustion engine, in order to optimize engine torque output spark timing control and boost pressure control are coordinated in such a manner that spark advance angle is adjusted only when the measured boost pressure equals a predetermined value and is allowed to vary only

In a turbocharged internal combustion engine, in order to optimize engine torque output spark timing control and boost pressure control are coordinated in such a manner that spark advance angle is adjusted only when the measured boost pressure equals a predetermined value and is allowed to vary only within a specified range advanced from a reference value derived from an empirical memory table on the basis of engine speed and boost pressure. When engine operating conditions are such that spark advance angle would fall outside of the specified range, spark advance angle is then held at the empirical value and boost pressure is adjusted in order to optimize engine torque. The coordinated control system can also be designed to respond to exhaust gas temperature on a first-priority basis, i.e., when exhaust temperature is sensed to be dangerously high, boost pressure is reduced regardless of other engine conditions.

대표청구항 ▼

An engine control system for a turbocharged internal combustion engine for controlling spark ignition timing and charge pressure in an air induction passage, comprising: first means for measuring engine speed and producing a first signal having a value representative of the engie speed; second means

An engine control system for a turbocharged internal combustion engine for controlling spark ignition timing and charge pressure in an air induction passage, comprising: first means for measuring engine speed and producing a first signal having a value representative of the engie speed; second means for measuring charge pressure in the air induction passage of the engine and producing a second signal having a value representative of the charge pressure; third means for detecting an engine knocking condition and producing a third signal indicative of the engine knocking condition; fourth means for controlling charge pressure relative to a given optimum pressure, said fourth means including an electrically-controlled valve for controlling said charge pressure; fifth means for controlling a spark advance angle within a predetermined variation range defined by predetermined extremes for defining the spark ignition timing; and sixth means for operating said fourth and fifth means in order to independently control charge pressure and spark ignition timing in accordance with the engine operating conditions represented by said first to third signals, said sixth means being responsive to said third signal to selectively operate one of said fourth and fifth means for knock prevention, said sixth means defining said variation range of said spark advance angle and said optimum charge pressure value and operating said fourth means to adjust said charge pressure while holding said spark advance angle at an angle adjacent one of said extremes and said fifth means to adjust said spark advance angle while holding said charge pressure at said optimum charge pressure value.