Evaporated fuel treatment device for engine

An evaporated fuel treatment device for an engine, the evaporated fuel treatment device comprising:

• an intake passage leading intake air to a combustion chamber of the engine;
• a throttle valve provided in the intake passage;
• a supercharger provided on a downstream side of the throttle valve in the intake passage;
• a bypass passage connecting an upstream side with a downstream side of the supercharger in the intake passage on a downstream side of the throttle valve and opening when the supercharger is not acting;
• and
• a purge passage leading evaporated fuel produced in a fuel tank to a section in the intake passage on a downstream side of the throttle valve and on an upstream side of the supercharger, the evaporated fuel treatment device being characterized in that
• when the supercharger is not acting, the intake passage generates a forward flow in which the intake air flows from the throttle valve toward the supercharger and a bypass-directed flow in which the intake air is reversed due to blockage of forward movement by the supercharger and flows from a side of the supercharger toward a connection port, of the bypass passage, opening in the intake passage on an upstream side of the supercharger, and
• an evaporated fuel introduction opening of the purge passage opens in a wall surface, on which the bypass-directed flow is generated, in the intake passage.