PURPOSE: To reliably prevent leak of vibration and noise, caused by intake air pulsation, to the outside, by a method wherein a supercharging intake air cooling means is disposed to the interior of a surge tank located in the middle part of an intake air passage situated down a line from a mechanical supercharger.
CONSTITUTION: An airflow meter 4, a throttle valve 5, a root blower type supercharger 6, a surge tank 7, and a fuel injector 8 are situated, in order named, from the upper stream side in an intake air passage 3 leading from an air cleaner 1 to an intake air port 2. In the engine with a supercharger, an intercooler 18, adapted to cool supercharging intake air, is disposed in the surge tank 7, and vibration noise, generated resulting from vibration of the fin of the intercooler 18 occasioned by pulsation of supercharging intake air, is prevented from leak to the outside. The intercooler 18 is connected to a radiator 21 for an intercooler, and is situated so that the supercharging intake air is cooled by means of cooling water circulated through driving of a water pump 22.
MORITA YASUYUKI
TOMINAGA KAZUNORI
