Combustible gas compressor

1. A combustible gas compressor comprising:

a compressor housing;

an impeller disposed in the compressor housing and configured to rotate to compress a combustible gas;

a motor housing;

a motor disposed in the motor housing and configured to drive the impeller disposed in the compressor housing;

a partition wall disposed between the compressor housing and the motor housing;

a rotational shaft connecting the motor and the impeller and configured to transmit rotation driving force of the motor to the impeller; and

a first bearing configured to support the rotational shaft; and

a second bearing configured to support the rotational shaft,

wherein the first bearing and the second bearing are disposed in the motor housing, and the motor is interposed between the first bearing and the second bearing,

wherein the first bearing is spaced from the partition wall and disposed between the partition wall and the motor, the first bearing being configured to lift the rotational shaft such that a bearing gap is formed between the first bearing and the rotational shaft,

wherein the compressor housing and the motor housing are integrally formed and partitioned by the partition wall,

wherein there is a leakage gap between the partition wall and the rotational shaft,

wherein the compressor housing is in fluid communication with the motor housing through the leakage gap between the rotational shaft and the partition wall configured to allow the combustible gas to leak from the compressor housing to the motor housing through the leakage gap between the rotational shaft and the partition wall such that the combustible gas received in the motor housing causes a pressure inside the motor housing to be higher than atmospheric pressure and inhibit external oxygen from flowing into the motor housing.

2. The combustible gas compressor according to claim 1 , wherein the motor is driven by a high speed frequency inverter and the impeller is directly connected to the motor without a separate set-up gear.

3. The combustible gas compressor according to claim 1 , further comprising a secondary compressor housing and a secondary impeller disposed in the secondary compressor housing, wherein the impeller and the compressor housing is disposed at one of both sides of the motor housing, and the secondary impeller and the secondary compressor housing are disposed at the other of both sides of the motor housing.

4. The combustible gas compressor according to claim 3 , wherein the compressor housing and the secondary compressor housing are connected to each other such that the combustible gas compressed while passing through the impeller is cooled by an intermediate cooler and then supplied to the secondary impeller such that the combustible gas is additionally compressed by the secondary impeller.

5. The combustible gas compressor according to claim 1 , wherein the partition wall between the motor housing and the compressor housing comprises a heat insulating member.

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

a pressure sensor configured to detect a pressure of an interior of the motor housing.

7. The combustible gas compressor according to claim 1 , wherein the motor housing comprises a supply hole through which an inert gas is supplied from an exterior to the motor housing and a vent hole through which an interior gas is discharged.

8. The combustible gas compressor according to claim 1 , wherein an interior of the motor housing is filled with the combustible gas.

9. The combustible gas compressor according to claim 1 , wherein the first bearing is a self-lubricating type bearing not using lubricant oil.