| 摘要 |
PROBLEM TO BE SOLVED: To provide a reliable screw compressor which, even if, for improving operation efficiency, a clearance between a screw rotor and a bearing support and a clearance between the screw rotor and a casing are each reduced, inhibits contact and seizure of them.SOLUTION: A screw compressor comprises; a screw rotor 2 which is housed in a casing 1 and has a plurality of spiral screw grooves 5 formed thereon; a gate rotor 3 that mates with the screw grooves 5 of the screw rotor 2 to form a compression chamber; a motor 20 that rotationally drives the screw rotor 2 connected thereto via a screw shaft 7; and a bearing support 4 that supports the screw shaft 7 via bearings 6 arranged on the discharge side of the screw rotor 2. At least one of oil and refrigerant liquid is injected from a flow passage formed in the casing 1 and in the bearing support 4 to communicate them, toward the screw rotor 2. A groove 13 is formed in a portion of the screw rotor 2 which is subjected to the injection of at least one of the oil and the refrigerant liquid.SELECTED DRAWING: Figure 1 |
