Patent ID: 7329108

Claim:
A scroll fluid machine comprising: a housing; a motor behind the housing; a driving shaft having an eccentric axial portion at one end and driven by the motor; a fixed scroll fixed in the housing and having a fixed wrap; an orbiting scroll having an orbiting wrap to form a sealed chamber between the fixed wrap and the orbiting wrap, said orbiting scroll being eccentrically revolved with the eccentric axial portion of the driving shaft so that the orbiting scroll is operable to compress a gas sucked in the sealed chamber from an outer circumference or a center of the housing towards the center and so that the orbiting scroll is operable to decompress and discharge the gas towards the outer circumference; a covering tube covering the housing such that a space is created between the covering tube and the housing; a blowing fan mounted to the driving shaft in the housing; and a primary sucking aperture opening to a primary passage formed in the space between a front face of the housing and the covering tube to communicate with the blowing fan, and a secondary sucking aperture opening to a secondary passage formed in the space between a rear part of the housing and the covering tube to communicate with the blowing fan and the primary passage, the primary passage being configured and positioned to introduce primary external air under decompression owing to rotation of the blowing fan, and the secondary passage being configured and positioned to introduce secondary external air under decompression owing to discharge of the primary external air to mix with the primary external air to cool the eccentric axial portion and parts of the driving shaft.