Abstract: A direct fuel injection-type spark-ignition internal combustion engine is disclosed. The engine comprises a spark plug, a cavity formed on the top surface of the piston, and a fuel injection valve for injecting fuel into the cavity in nearly the flat fan shape having a relatively small thickness. An opposing side wall of the cavity opposite to the fuel injection valve, for leading the fuel to the vicinity of the spark plug, has an arcuate portion having a plurality of arcuate shapes in a plan view. The radius of arcuate shape at the both side parts of the arcuate portion in a plan view is smaller than the radius of arcuate shape at the center part of the arcuate portion in a plan view. The opposing side wall has a deflecting portion to deflect the fuel toward the inside of the cavity.

Abstract: A direct fuel injection-type spark-ignition internal combustion engine is disclosed. The engine comprises a cavity formed on the top surface of the piston, a spark plug facing the inside of said cavity, and a fuel injection valve for injecting fuel into the cavity in nearly the shape of a fan having a relative small thickness. The cavity has a bottom wall onto which the injected fuel impinges initially and a side wall facing to the fuel injection valve. The side wall has a deflection portion which is nearly the shape of a linear line and a circular arc portion which connects the deflection portion and the bottom wall smoothly in a vertical section. An angle of the deflection portion with the bottom wall is in a range from 50 to 80 degrees. A radius of the circular arc portion is in a range from 5 to 15 mm.

Abstract: A device for detecting deterioration of a catalyst in an internal combustion engine having a heater on the upstream side of a catalytic converter provided in an exhaust gas passage, the device being capable of expanding the deterioration determination conditions of the catalyst. It is determined whether the conditions, except the temperature condition, are all obtained among the conditions for detecting deterioration of the catalytic converter. When the conditions, except the temperature condition, are all obtained, an electric power is supplied from a power source to the heater to satisfy the temperature condition. Deterioration of the catalyst can be reliably detected if the electric power is supplied to the heater only when the engine is in the idling operation condition and if deterioration of the catalyst is detected when the time for supplying electric power to the heater has become larger than a predetermined period of time. The heater may be one contained in the electrically heated catalyst.

Abstract: An onboard load control apparatus and a method for detecting a fault of an onboard electrical load with high accuracy are disclosed. The control apparatus comprises an onboard battery mounted on an automotive vehicle, an electrical heater for electrically heating an electrical load such as an electrically-heated catalyst supplied with power from the onboard battery, an auxiliary relay for turning on/off the power to the electrical heater from the onboard battery, and an ECU for controlling the on/off operation of the auxiliary relay. The apparatus further comprises an engine speed detector for detecting the engine speed of the internal combustion engine and a fault judgement unit for judging whether the electrical heater is normal or faulty on the basis of the fluctuation amount of the engine speed of the internal combustion engine detected by the engine speed detector before and after switching the auxiliary relay.