Leak recovery structure of screw compressor in shaft seal

摘要

Problem to be solved: to provide a leakage oil recovery structure in a shaft seal of a screw compressor capable of efficiently recovering leakage oil.Solution: an oil storage space 34 for sealing lubricating oil leaked from the shaft sealing device 60 is provided around the drive shaft 20 at a position closer to the outer side of the casing 30 to the shaft sealing device 60 by sealing the inner circumference of the shaft hole 32 provided in the casing 30 and the outer circumference of the drive shaft 20 by the shaft sealing device 60.A small diameter portion nd of the drive shaft 20 disposed in the oil reservoir space 34 is provided with a small diameter portion Nd on the side of the shaft sealing device 60, a large-diameter portion WD close to the outside of the casing 30, a step portion 23 is provided at a boundary portion of a small diameter portion nd and a large diameter portion WD, and a tapered portion 24 is formed in the large diameter portion WD which is located outside the casing 30 to narrow the diameter gradually toward the outside of the casing An end 24a of the tapered portion 24 on the large diameter side is disposed in the oil reservoir space 34.Diagram