| 主权项 |
1. A control device for a spark-ignition engine, the device comprising:
an engine body configured to run with a fuel including an unconventional fuel, of which the vaporization rate is lower, at or below a specific temperature, than that of the gasoline; a fuel feeder configured to feed the fuel into a cylinder provided for the engine body; and a controller configured to operate the engine body by controlling at least the fuel feeder, wherein if the engine body is under a load greater than a predetermined load, the controller is configured to:
select a first fuel feeding mode in which a larger amount of the fuel is fed during a compression stroke than during an intake stroke if the engine body has a temperature which is equal to or below a predetermined temperature; andselect a second fuel feeding mode in which a larger amount of the fuel is fed during the intake stroke than during the compression stroke if the engine body has a temperature which is higher than the predetermined temperature, the amount of the fuel to be fed by the fuel feeder is obtained by making an augmenting correction to a basic fuel feeding amount to be set based on a running state of the engine body, using a correction factor which has been set in advance based on a vaporization rate of the fuel, the vaporization rate being a ratio by weight of the fuel contributing to combustion to the fuel fed into the cylinder, and in response to a fall in the vaporization rate immediately after a switch from the first fuel feeding mode to the second fuel feeding mode as the temperature of the engine body rises so much as to exceed the predetermined temperature, the controller is configured to set the correction factor immediately after the switch to be greater than that before the switch. |
