FLUIDIC TYPE GAS METER

PROBLEM TO BE SOLVED: To facilitate mass production through molding of a valve disc 42. SOLUTION: A pressure change removing means 37 and a fluidic flowmeter 36 are provided sequentially in this order along a gas passing direction at the gas channel of a as meter body 35. One end 112 of a connecting rod 70 is mounted oscillatingly at a valve disc 42 which can be seated a valve seat 82, and the other end of the rod 70 is coupled to the diaphragm 43. The diaphragm 43 approaches the disc 42 to a valve seat 48, as the pressure difference between the pressure of an upstream side from a valve hole 41 and the pressure of a gas exhaust port side becomes smaller. An annular protrusion 132 of the disc 2, a contact surface 135 perpendicular to an axis 42a of the disc 42 and a circular arc surface 136, having a quadrant sectional shape connected to the surface 135, are formed. In this case, a radius Rc of the surface 136 is selected to be in the range of 0.3 to 1.0 mm.