In one example embodiment, a method includes depositing one or more thin-film layers onto a substrate. In a final stage of the insertion, the female and male couplers are connected with each other with the first and second sealing rings being kept covered by the front end portions of the primary movable valve member 38 and the movable valve member 15, respectively. The producing method further includes a molding of a second casing to seal the second face of the circuit board and the electronic parts mounted on the second face.