Vacuum pump

Abstract

The present invention provides a vacuum pump capable of suppressing the structure from becoming complicated and improving the damping effect. The vacuum pump includes: a holding mechanism for clamping an outer race of the ball bearing in an axial direction and holding the outer race so that the outer race moves along a radial direction; and an elastic member disposed at an outer circumferential side of the outer race. The elastic member is disposed in contact with or close to the outer circumferential side of the outer race. Oil or grease is injected into a gap between the elastic member and the outer race. Through holding the outer race against the elastic member, the elastic member is deformed to suppress vibration. Furthermore, through injecting oil or grease into the gap, the damping effect can be further improved.

What is claimed is: 
     
         1 . A vacuum pump using a ball bearing for supporting a rotor formed with an exhaust function portion and using a motor to make the rotor rotate for vacuum exhaustion, comprising:
 a holding mechanism, clamping an outer race of the ball bearing in an axial direction and holding the outer race in a manner that the outer race is adapted to moves along a radial direction;   a housing, formed on a pump seat and accommodating the holding mechanism; and   an elastic member, located in the housing and disposed in contact with or close to an outer circumferential side of the outer race.   
     
     
         2 . The vacuum pump according to  claim 1 , wherein
 the elastic member is a ring-shaped elastic member disposed in a manner of surrounding an outer circumference of the outer race through a gap; and   at least oil or grease is injected into the gap.   
     
     
         3 . The vacuum pump according to  claim 2 , wherein
 an outer circumferential side gap is formed between the outer circumference of the elastic member and the housing; and   the oil or the grease is injected into the outer circumferential side gap.   
     
     
         4 . The vacuum pump according to  claim 1 , wherein
 the elastic member is a ring-shaped elastic member disposed in a manner of contacting with an axial centre of an outer circumferential surface of the outer race and arranged in a manner of forming a gap between the outer circumferential surface of the outer race and the housing; and   at least oil or grease is injected into the gap.   
     
     
         5 . The vacuum pump according to  claim 1 , wherein:
 the elastic member is made of metal.   
     
     
         6 . The vacuum pump according to  claim 1 , wherein
 the holding mechanism includes:   a pair of pressure plates, respectively disposed at two axial ends of the outer race; and   an elastic support member, disposed between each of the pair of pressure plates and the housing.