Evaporated fuel processing device

An evaporated fuel processing device configured to supply evaporated fuel evaporated in a fuel tank to an intake pipe, through which air is supplied to an internal combustion engine, the intake pipe including a supercharger and a throttle valve provided at a position downstream of the supercharger, the evaporated fuel processing device comprising:

• a canister configured to adsorb the fuel evaporated in the fuel tank;
• a purge passage that connects the canister and the intake pipe, and through which a purge gas sent from the canister to the internal combustion engine passes;
• a purge control valve provided on the purge passage;
• and
• an ejector provided on the intake pipe in parallel to the supercharger,
• wherein
• the purge passage branches into a first branch passage and a second branch passage at a position downstream of the purge control valve,
• the first branch passage is connected to the intake pipe at a position downstream of the throttle valve,
• the second branch passage is connected to a suction port of the ejector,
• an intake port of the ejector is connected to the intake pipe at a position between the supercharger and the throttle valve,
• an exhaust port of the ejector is connected to the intake pipe at a position upstream of the supercharger,
• the evaporated fuel processing device is configured to obtain a flow rate of the purge gas passing through the second branch passage based on a first pressure in the intake pipe downstream of the throttle valve, a second pressure in the intake pipe between the supercharger and the throttle valve, and a third pressure in the intake pipe upstream of the supercharger, and
• the flow rate of the purge gas passing through the second branch passage is obtained by multiplying a flow rate and a correction coefficient, the flow rate being obtained based on a table related to the flow rate of the purge gas with the differential pressure between the second pressure and the third pressure as a variable, and the correction coefficient being obtained based on a table related to the correction coefficient of the purge gas with the differential pressure between the first pressure and the third pressure as a variable.