CONTROL DEVICE FOR COMPRESSION IGNITION-TYPE ENGINE

摘要

A control device for a compression ignition engine includes a controller configured to operate an engine body by compression ignition combustion when the engine body operates in a predetermined compression ignition range. When the engine body operates in a predetermined high load range of the compression ignition range, the controller maximizes a filling amount of the cylinder using a gas state adjustment system, and lowers an EGR ratio so that the air-fuel mixture in the cylinder is lean with an excess air ratio λ higher than 1 in a lower speed range, and maximizes the filling amount of the cylinder, and increases the EGR ratio so that the air-fuel mixture in the cylinder has the excess air ratio λ of 1 or lower in a higher speed range than the lower speed range.

主权项

1. A control device for a compression ignition engine
an engine body including a cylinder; a fuel injection valve configured to inject fuel into the cylinder; a gas state adjustment system configured to adjust a ratio of an amount of fresh air introduced into the cylinder to an amount of exhaust gas to adjust a gas state of the cylinder; and a controller configured to operate the engine body by compression ignition combustion of an air-fuel mixture in the cylinder when the engine body operates in a predetermined compression ignition range, wherein when the engine body operates in a predetermined load range of the compression ignition range, which is higher than a predetermined load, the controller
fully opens a throttle valve using the gas state adjustment system, and lowers an EGR ratio, which is a ratio of an amount of the exhaust gas to an entire amount of gas in the cylinder so that the air-fuel mixture in the cylinder is lean with an excess air ratio λ higher than 1 in a lower speed range, in which an engine speed is lower than a predetermined speed, andfully opens the throttle valve, and increases the EGR ratio so that the air-fuel mixture in the cylinder has the excess air ratio λ of 1 or lower in a higher speed range, in which the engine speed is higher than that in the lower speed range.