METHOD FOR PROVIDING ACTUAL EXPANDING STROKE DURING EXPANSION STROKE LONGER IN TERMS OF STROKE THAN IN ACTUAL COMPRESSING STROKE DURING COMPRESSION STROKE FOR DIRECT INJECTION FOUR-CYCLE ENGINE AND COUNTERMEASURE FOR A CASE OF TOO LONG STROKE

摘要

PROBLEM TO BE SOLVED: To provide a method for providing an actual expanding stroke during an expansion stroke longer in terms of a piston stroke than in an actual compressing stroke during a compression stroke for a direct injection four-cycle engine the a countermeasure for when it is too long. ;SOLUTION: A valve is provided opening at a bottom dead center and closing just before a top dead center during the compression stroke {valve c [an exhaust valve may double this movement (valve b)]}. As a countermeasure when the valve opening at the bottom dead center and closing just before the top dead center during the compression process is opened too long, a valve is provided opening before a resistance of rotation occurs due to excessive expansion (atmospheric pressure becomes 1 atm or less) during the expansion stroke and closing at the bottom dead center {valve d [an intake valve may double this movement (valve a)]}.;COPYRIGHT: (C)2001,JPO