To resolve a problem of decreasing a heat exchange rate of a refrigerating cycle owing to a large amount of a refrigerator oil delivered from a discharge pipe to the refrigerating cycle, there is provided a sealed compressor driven by a motor having a compressor unit and a motor unit in which a ring is provided at an outer periphery of a coil end of a stator on a side of the compressor unit to reduce the amount of delivering the refrigerator oil to the refrigerating cycle and a shape of a balance weight of a rotor on the side of the compressor unit is formed in a cylindrical shape a portion of a side face of which is opened and an end face of which is flat to thereby reduce stirring of fluid.