SEALED COMPRESSOR AND REFRIGERATION UNIT INCLUDING SEALED COMPRESSOR

1 . A sealed compressor comprising:

an electric component including a stator and a rotor;

a compression component actuated by the electric component; and

a sealed container accommodating the electric component and the compression component and storing lubricating oil for lubricating the compression component;

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 accommodating a piston reciprocatable according to rotation of the shaft, a main bearing unit mounted on the cylinder block to support the main shaft section, and a thrust ball bearing disposed between a flange surface formed in the shaft and a thrust surface formed in the main bearing unit;

the main shaft section is provided with a first oil feeding passage to transport the lubricating oil from a lower portion of the main shaft section to an upper portion of the main shaft section;

the thrust ball bearing includes a plurality of balls held in a cage, an upper race disposed such that one of its main surfaces is in contact with upper portions of the balls; and a lower race disposed such that one of its main surfaces is in contact with lower portions of the balls;

the main surface of the upper race and the main surface of the lower race face each other;

at least one of the main surface of the upper race and the main surface of the lower race, the main surfaces facing each other, is provided with a raceway groove which is formed by an annular groove, and in which the balls are placed;

the thrust ball bearing is provided with a second oil feeding passage communicated with the first oil feeding passage and configured to feed the lubricating oil to the raceway groove and a discharge passage through which the lubricating oil fed to the raceway groove is discharged to outside of the thrust ball bearing and;

the thrust surface is provided with a discharge hole to discharge the lubricating oil.

2 . The sealed compressor according to claim 1 ,

wherein the thrust surface is defined by an inner bottom surface of a recess formed in a main surface which is an upper surface of the main bearing unit; and

the main surface of the main bearing unit is disposed below a lower surface of the cage.

3 . (canceled)

4 . The sealed compressor according to claim 1 , further comprising:

a snubber provided at a lower portion of an electric and compression component including the electric component and the compression component;

a shell snubber provided at an inner bottom surface of the sealed container to face the snubber; and

a coil spring through which the snubber and the shell snubber are inserted, the coil spring being configured to elastically support the electric and compression component;

wherein a distance between a lower end portion of the shaft and an inner bottom surface of the sealed container is greater than a distance between a lower end of the snubber and an upper end of the shell snubber.

5 . The sealed compressor according to claim 1 ,

wherein the cage has an inner diameter greater than an inner diameter of the upper race and an inner diameter of the lower race.

6 . The sealed compressor according to claim 1 , further comprising:

an inverter unit;

wherein the sealed compressor is actuated by the inverter unit by rotational speeds of two or more kinds, including a rotational speed lower than a power supply frequency.

7 . A refrigeration unit comprising the sealed compressor according to claim 1 .