Valve device with cleaning wire

A valve device comprising:

• a valve body configured to open and close a valve hole allowing communication between a primary side and a secondary side of a flow path;
• a back pressure chamber positioned at a back side of the valve body;
• a small hole in the valve body to allow communication between the primary side of the flow path and the back pressure chamber;
• and
• a pin comprising a straight portion inserted into the small hole to clean the small hole by relative motions of the small hole and the straight portion,
• wherein
• the pin has a contact portion that extends radially at a first end of the straight portion, that extends circumferentially to wind around the straight portion by one or less turns, and contacts a peripheral edge of the small hole,
• the contact portion is inclined in a direction from the straight portion first end to a straight portion second end, and
• the pin comprises a retaining portion that bends at the straight portion second end and extends toward a leading end.