Patent ID: 8511338

Claim:
A water flow detection device comprising: a main body having a valve body that employs a structure of a swing check valve; a detection rod provided so as to pass through the main body from the inside of the main body to the outside, the detection rod being rotatably supported by a pin having an axial direction that orthogonally intersects a direction in which water flows; an urging unit that urges the detection rod such that the detection rod contacts the valve body; a switch that outputs signals in response to the rotation of the detection rod, wherein the pin that supports the detection rod is provided inside a hollow retainer, the retainer is disposed between the main body and the switch, and the retainer has a holding unit that holds the pin at a position at which the axial direction of the pin intersects the direction in which water flows; and an extended block provided between the main body and the switch, the extended block having a receiving portion that mates with an engagement portion formed on a surface of the retainer as the holding unit, wherein the engagement portion is provided in the form of any of a protrusion, a hole, and a cutout.