Blow-by gas recirculation device

A blow-by gas recirculation device configured to recirculate blow-by gas to an intake passage of a turbocharged engine that includes a compressor installed in the intake passage and an intercooler installed at a portion of the intake passage on a downstream side of the compressor, the blow-by gas recirculation device being provided in a crankcase, and comprising:

• a first passage through which a first portion of the intake passage, on the downstream side of the compressor and on an upstream side of the intercooler, is communicated with the crankcase;
• a second passage through which a second portion of the intake passage, on a downstream side of the intercooler, is communicated with the crankcase;
• a third passage through which a third portion of the intake passage, on an upstream side of the compressor, is communicated with the crankcase;
• and
• a switching mechanism that is configured to switch between a first state and a second state, the first state being a state in which the first passage communicates the first portion of the intake passage with the crankcase, and the communication between the second portion of the intake passage and the crankcase via the second passage is blocked, and the second state being a state in which the communication between the first portion of the intake passage and the crankcase via the first passage is blocked, and the second passage communicates the second portion of the intake passage with the crankcase.