US Patent 7438062 Flow passage switching valve

A flow passage switching valve provided with a swing arm type valve element comprises a housing formed with a first passage communicated with an inlet port, a second passage communicated with an outlet port, a bypass passage for providing communication between the first passage and the second passage, an introduction port through which a fluid flowing in the first passage is introduced into an external part, and a discharge port through which the fluid introduced into the external part is discharged into the second passage.