PROBLEM TO BE SOLVED: To provide a compressed air flow control valve device for a compressed air driving type handpiece, capable of highly accurately machining a flow control valve element to prevent unevenness in the compressed air flow for each product, and having a structure without requiring flow control whenever the handpiece is assembled.SOLUTION: The compressed air flow control valve device 50 for the air driving type hand piece 10 includes a valve element 62 which slides along a valve seat 56 with a compressed air outlet opening 60. An arc-shaped notch 66 is formed in the valve element. The notch 66 can be formed by working by connecting spot facing holes 66A, 66B and 66C with different spot facing depths D on three stages connected to an NC milling machine. As the compressed air flow is determined by the spot facing depth D of one of the spot facing hole 66A, 66B or 66C facing the outlet opening 60 of the valve seat 56, flow control at the time of assembly is not necessary if only numerical control of the spot facing depth of each spot facing hole is closely managed.COPYRIGHT: (C)2013,JPO&INPIT【課題】製品毎に圧縮空気流量のバラツキが生じることがないように流調弁要素を高精度で機械加工することができ、組立時にいちいち流量調節をする必要のない構造を有する、圧縮空気駆動式歯科用ハンドピースの圧縮空気流調弁装置を提供する。【解決手段】空気動式歯科用ハンドピース10の圧縮空気流調弁装置50は、圧縮空気出口開口60を備えた弁座56に沿って摺動する弁体62を有し、この弁体には円弧状に切欠き66が形成してある。切欠き66は、NC制御フライス盤により3段階に異なる座ぐり深さDを有する座ぐり孔66A、66B、66Cを繋げて加工することにより形成することができる。圧縮空気流量は弁座56の出口開口60に対面するいずれかの座ぐり孔66A、66B、66Cの座ぐり深さDにより定まるので、夫々の座ぐり孔の座ぐり深さを精密にNC管理しさえすれば組立時の流量調節が不要になる。【選択図】図2
