Patent ID: 6953330
Filing Date: 2005-10-11
Classification: F04C

Abstract:
1. A scroll vacuum pump comprising: a housing; a driving shaft along a center of the housing, said driving shaft having an eccentric portion, a fixed scroll fixed in the housing, said fixed scroll having a fixed wrap; and an orbiting scroll rotatably mounted around the eccentric portion of the driving shaft and having an orbiting wrap, the orbiting scroll being revolved eccentrically by the driving shaft so that a gas sucked through an outer circumference of the housing is compressed toward the center of the housing in a compression chamber between the fixed and orbiting wraps engaged with each other and discharged, thereby sucking a gas into the compression chamber, said driving shaft having a ventilating hole that communicates with outside and extends axially therein, a valve bore that radially extends communicating with the ventilating hole at one end and opening to the compression chamber at the other end, said valve bore having a check valve that opens by centrifugal force when the driving shaft rotates thereby introducing external air into the compression chamber for cooling, while the check valve closes when the driving shaft stops thereby preventing the gas from being leaked from the compression chamber to the outside.