PROBLEM TO BE SOLVED: To provide a bathtub with a microbubble generator that does not reduce the amount of microbubbles in bath water discharged form a discharge port even when the rotation rate of a pump part is reduced.SOLUTION: The bathtub 1 includes: a circulating flow passage 2 provided between a suction port 11 and discharge port 12 thereof an air mixing part 4 connected to the middle of the circulating flow passage 2 the pump part 5 a gas-liquid dissolving part 6 a pressure control valve 7 and a control part 8 for controlling the rotation rate of the pump part 5. An opening adjuster is provided to set the opening of the pressure control valve 7 to be a predetermined opening when the pump part 5 rotates at a predetermined rotation rate, and to set the opening of the pressure control valve 7 to be smaller than the predetermined opening when the pump part 5 rotates at a lower rotation rate than the predetermined rotation rate.COPYRIGHT: (C)2012,JPO&INPIT【課題】ポンプ部の回転数を低下させて運転しても、吐出口から吐出される浴水中の微細気泡の量が減少してしまうことのない微細気泡発生装置付き浴槽を提供する。【解決手段】浴槽1の吸込口11と吐出口12との間に設けられる循環流路2と、前記循環流路2の途中に接続される空気混入部4とポンプ部5と気液溶解部6と圧力制御弁7と、前記ポンプ部5の回転数を制御する制御部8と、を備える。前記ポンプ部5が所定の回転数で回転する際に前記圧力制御弁7の開度を所定の開度とすると共に、前記ポンプ部5が前記所定の回転数よりも低い回転数で回転する際に前記圧力制御弁7の開度を前記所定の開度よりも小さい開度とする開度調節手段が設けられる。【選択図】図1
