Turbo compressor and refrigerator

1. A turbo compressor comprising:

a case divided into a motor housing, a gear housing, and a compressor housing;

a plurality of compression stages which are disposed rotatably with respect to the case via sliding parts, each of the plurality of compression stages including an impeller;

an oil tank disposed in the gear housing, lubricant oil to be supplied to the sliding parts being stored in the oil tank;

a motor in the motor housing for rotating the plurality of the impellers included in the plurality of the compression stages via the sliding parts;

an oil cooler for cooling the lubricant oil;

primary piping connecting the oil tank with the oil cooler; and

secondary piping connecting the oil cooler with the sliding parts,

wherein the gear housing includes an accommodation space which is located above the oil tank and configured to communicate with the oil tank, and

the accommodation space is configured to accommodate a first part of the sliding parts, the oil cooler, part of the primary piping, and part of the secondary piping.

2. The turbo compressor according to claim 1 ,

wherein at least a part of the primary piping and the secondary piping is embedded into a wall surface of the case.

3. A refrigerator comprising:

a condenser that cools and liquefies a compressed refrigerant;

an evaporator which cools a material to be cooled by evaporating a liquefied refrigerant to take a vaporization heat from the material to be cooled; and

a turbo compressor which compresses a refrigerant evaporated by the evaporator to supply the refrigerant to the condenser,

wherein the turbo compressor according to claim 1 is used as the turbo compressor.

4. A refrigerator comprising:

a condenser that cools and liquefies a compressed refrigerant;

an evaporator which cools a material to be cooled by evaporating a liquefied refrigerant to take a vaporization heat from the material to be cooled; and

a turbo compressor which compresses a refrigerant evaporated by the evaporator to supply the refrigerant to the condenser,

wherein the turbo compressor according to claim 2 is used as the turbo compressor.

5. The turbo compressor according to claim 1 ,

wherein the sliding parts include:

a first bearing which is fixed to the motor housing and configured to rotatably support an output shaft of the motor,

a second bearing which is fixed to the gear housing and configured to rotatably support a rotational shaft of the plurality of the impellers via one end of the rotational shaft,

a third bearing which is fixed to the compressor housing and configured to rotatably support the rotational shaft of the plurality of the impellers via the other end of the rotational shaft, and

a gear unit which includes one gear fixed to the output shaft of the motor and another gear fixed to the rotational shaft of the plurality of the impellers, and

wherein the secondary piping includes:

a first piping which is configured to supply the lubricant oil to the first bearing,

a second piping which is configured to supply the lubricant oil to the second bearing, and

a third piping which is configured to supply the lubricant oil to the third bearing.

6. The turbo compressor according to claim 5 ,

wherein the compressor housing includes a space formed therein, and the space is configured to accommodate the third bearing.

7. The turbo compressor according to claim 6 ,

wherein the oil tank is configured to communicate with the space formed in the compressor housing.

8. The turbo compressor according to claim 1 ,

wherein the oil tank is configured to communicate with a space which is configured to accommodate a second part of the sliding parts.