Sealed compressor and refrigeration unit comprising sealed compressor

A sealed compressor comprising:

• an electric component including a stator and a rotor;
• a compression component actuated by the electric component;
• a sealed container which accommodates the electric component and the compression component and stores lubricating oil therein;
• wherein the compression component includes a shaft including a main shaft section to which the rotor is fastened and an eccentric shaft section, a cylinder block having a compression chamber, a piston reciprocatable inside the compression chamber, a connecting member for coupling the piston to the eccentric shaft section, and a main bearing unit mounted to the cylinder block and supporting the main shaft section such that the main shaft section is rotatable, a thrust ball bearing mounted to a thrust surface of the main bearing unit;
• and the thrust ball bearing includes a plurality of balls held in a cage, an upper race having main surfaces one of which is in contact with upper portions of the balls;
• and a lower race having main surfaces one of which is in contact with lower portions of the balls and;
• at least one limiting means for limiting a displacement of the upper race with respect to the shaft;
• wherein raceway grooves formed by annular grooves are provided on the main surface of the upper race and the main surface of the lower race, respectively, the main surfaces facing each other;
• and
• wherein the balls are placed on the raceway groove of the upper race and the raceway groove of the lower race.