| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent accidental fire by EGR gas during deceleration in an engine with a supercharger having an EGR device. <P>SOLUTION: An exhaust pressure reduction control for reducing an exhaust pressure during deceleration of an engine 11 (for example, a control for opening a waste gate valve 27 or a control to delay the closing timing of an exhaust valve to the vicinity of a top dead center, or the like) is carried out, and thereby promoting exhaust of an internal EGR gas (combustion gas remaining in a cylinder) to reduce an amount of the internal EGR gas. Thereby, even when an external EGR gas remaining in an intake pipe 12 during deceleration (EGR gas refluxed by an EGR device 28) is excessively present, increase in the amount of the total EGR gas, with which the inside of the cylinder is filled, (sum of the external EGR gas amount and the internal EGR gas amount) is suppressed or the amount of the total EGR gas, with which the inside of the cylinder is filled, is reduced to prevent accidental fire by the EGR gas during deceleration even under such conditions that a control of cutting a fuel cannot be carried out. <P>COPYRIGHT: (C)2012,JPO&INPIT |
