Compressor with oil-mist separator

A compressor for compressing a mixture gas including a mist of lubrication oil and a gas to be taken out of the compressor with a pressurized condition, comprising,

• a pair of compressing members movable with respect to each other so that the mixture gas is compressed therebetween,
• a motor for driving at least one of the compressing members to generate a relative movement between the compressing members for compressing the mixture gas, and
• an oil-mist separator for separating the mist of lubrication oil from the mixture gas to collect the lubrication oil,
• wherein the oil-mist separator includes an inner surface forming a chamber for receiving the mixture gas, an inlet passage for directing a flow axis of the mixture gas when the mixture gas reaches the chamber, and a discharge passage including a discharge port opening in the chamber to discharge the gas from the chamber through the discharge port, wherein the inner surface of the oil-mist separator includes a groove having a spiral shape whose axis extends vertically, the spiral shape being formed in such a manner that the mixture gas is urged vertically downward by the groove when the mixture gas whose flow axis is directed by the inlet passage proceeds circumferentially in the chamber, and wherein an imaginary extension line of a lower end of the inlet passage traverses the groove having the spiral shape as seen in a direction perpendicular to the axis of the groove having the spiral shape.