PROBLEM TO BE SOLVED: To provide an oxygen concentrator by which noise reduction can be realized when oxygen supplying amount is small.SOLUTION: The oxygen concentrator includes two sets of three-way selector valves 109a and 109b which are connected between the inlet sides of two adsorbing cylinder bodies 108a and 108b and a compressor 105, a pressure-equalizing valve 107, an oxygen supplying amount setting portion 8 to set an oxygen supplying amount of 0.1-3 L/min, a first vacuum break valve 120 which exhausts when the flow amount of oxygen is set to be in the range of 1-3 L/min and, in addition, a second vacuum break valve 121 which is opened and exhausts for pressure equalization when the flow amount of oxygen is set to be less than 1 L/min.COPYRIGHT: (C)2008,JPO&INPIT【課題】 酸素供給量が小さいときに低騒音化を実現可能にした酸素濃縮装置の提供。【解決手段】2本の吸着筒体108a、108bの入口側とコンプレッサ105の間に接続される2組の3方向切換弁109a、109bと、均等圧弁107と、酸素供給量を毎分0.1~3リットルの範囲で設定する酸素供給量設定部8と、酸素流量が毎分約1~3リットルに設定されると排気を行う第1負圧破壊弁120に加えて、酸素流量が毎分1リットル未満に設定されると均等圧化を行うときに開状態にされて排気を行う第2負圧破壊弁121とを備える。【選択図】 図7
