Sealed compressor and vapor compression refrigeration cycle apparatus including the sealed compressor

A vapor compression refrigeration cycle apparatus comprising:

• a sealed compressor comprising:
• a sealed container that stores lubricant oil at a bottom thereof,
• a motor that is provided within the sealed container and has a stator and a rotor,
• a drive shaft attached to the rotor,
• a compression mechanism that is provided within the sealed container and configured to compress a refrigerant upon rotation of the drive shaft,
• a centrifugal impeller that is provided above the rotor and configured to rotate in synchronization with the rotor,
• a rotor air hole that penetrates the rotor in an up-down direction, and
• a discharge pipe configured to cause the refrigerant, upon flowing into a lower space of the motor, rising through the rotor air hole, and flowing into an upper space of the motor, to flow out from the upper space to an external circuit of the sealed container,
• wherein the centrifugal impeller includes:
• an oil separation plate and a lower surface partition plate that are provided on an upper side of an upper end of the rotor so as to be spaced apart from each other,
• a plurality of vanes that stand downwards from a lower surface of the oil separation plate and are provided from an inner peripheral side toward an outer peripheral side, and
• inter-vane flow passages each provided between two adjacent vanes of the plurality of vanes, and a vane inner flow passage that guides the refrigerant, upon flowing out from the rotor air hole, to inner peripheral entrances of the inter-vane flow passages,
• wherein the inter-vane flow passages are arranged along an entire circumference to guide the refrigerant from the inner peripheral entrances thereof to outer peripheral exits thereof, and cause the refrigerant increased in pressure while passing through the inter-vane flow passages to flow out from the outer peripheral exits into the upper space, and
• wherein the oil separation plate covers an upper surface of the inter-vane flow passages to close an upper end of the vane inner flow passage, and the lower surface partition plate covers a lower surface of the inter-vane flow passages to close a short-circuit passage through which the refrigerant that has risen through the rotor air hole directly flows out to the discharge pipe without passing through the inter-vane flow passages;
• a radiator that rejects heat from the refrigerant compressed by the sealed compressor;
• an expansion mechanism that expands the refrigerant, upon flowing out of the radiator;
• and
• an evaporator that causes the refrigerant, upon flowing out of the expansion mechanism, to receive heat.