Vacuum pump

Abstract

A heater 29 is mounted on the outer peripheral surface of a base 6 to heat the base 6 . A heat shutoff wall 24 b is provided on a motor housing 24 to prevent the radiation heat of the base 6 heated by the heater 29 from transferring to a pump inside substrate 25 . A gap portion 27 is formed by providing a gap between the motor housing 24 and the base 6 to prevent the heat of the base 6 heated by the heater 29 from transferring to the motor housing 24 . Also, a water cooled tube 28 is installed under the motor housing fixing portion 24 c and cooling water is circulated in the tube to efficiently cool the pump inside substrate 25 . By constructing a vacuum pump in this manner, the accumulation of solid product of process gas in the vacuum pump is restrained, and thus the pump inside substrate can be cooled efficiently.

What is claimed is:  
     
         1 . A vacuum pump comprising: 
 a body which has a casing and a base and is provided with a gas intake port and a gas discharging port;    a rotor pivotally supported in said body so as to be rotatable;    a motor for driving said rotor;    a motor housing which is located in said body and is fixed to said base;    gas transfer means, which is provided between said casing and said rotor, for transferring gas sucked through said gas intake port to said gas discharge port;    heating means for heating a gas discharge path for the gas transferred by said gas transferring means;    a pump inside substrate which is disposed in said base and said motor housing and is mounted with a predetermined circuit; and    heat shutoff means for shutting off heat transfer from said base to said pump inside substrate and motor.    
     
     
         2 . The vacuum pump according to  claim 1 , wherein said heat shutoff means is a heat shutoff wall integrally formed at the end on the base side of said motor housing, and 
 said motor housing is fixed to said base via said heat shutoff means.    
     
     
         3 . The vacuum pump according to  claim 2 , wherein said heat shutoff wall has a flange portion on the end face opposite to said motor housing, and 
 said motor housing is fixed to said base via said flange portion.    
     
     
         4 . The vacuum pump according to  1 , wherein said vacuum pump further comprises cooling means for cooling said motor housing.  
     
     
         5 . The vacuum pump according to  2 , wherein said vacuum pump further comprises cooling means for cooling said motor housing.  
     
     
         6 . The vacuum pump according to  3 , wherein said vacuum pump further comprises cooling means for cooling said motor housing.  
     
     
         7 . The vacuum pump according to  claim 4 , wherein said cooling means is a water cooled tube provided on said motor housing to circulate cooling water.  
     
     
         8 . The vacuum pump according to  claim 5 , wherein said cooling means is a water cooled tube provided on said motor housing to circulate cooling water.  
     
     
         9 . The vacuum pump according to  claim 6 , wherein said cooling means is a water cooled tube provided on said motor housing to circulate cooling water.  
     
     
         10 . A vacuum pump comprising: 
 a body which has a casing and a base and is provided with a gas intake port and a gas discharging port;    a rotor pivotally supported in said body so as to be rotatable;    a motor for driving said rotor;    a motor housing which is located in said body and is fixed to said base;    gas transfer means, which is provided between said casing and said rotor, for transferring gas sucked through said gas intake port to said gas discharge port;    heating means for heating a gas discharge path for the gas transferred by said gas transferring means;    a pump inside substrate which is disposed in said base and said motor housing and is mounted with a predetermined circuit; and    heat insulating means provided on the opposing surface of said motor housing and said base.    
     
     
         11 . The vacuum pump according to  claim 10 , wherein said heat insulating means is a gap or a heat insulating material.  
     
     
         12 . The vacuum pump according to  claim 10 , wherein said vacuum pump further comprises heat shutoff means for shutting off heat transfer from said base to said pump inside substrate and motor.  
     
     
         13 . The vacuum pump according to  claim 11 , wherein said vacuum pump further comprises heat shutoff means for shutting off heat transfer from said base to said pump inside substrate and motor.  
     
     
         14 . The vacuum pump according to  claim 12 , wherein said heat shutoff means is a heat shutoff wall integrally formed at the end on the base side of said motor housing, and 
 said motor housing is fixed to said base via said heat shutoff means.    
     
     
         15 . The vacuum pump according to  claim 13 , wherein said heat shutoff means is a heat shutoff wall integrally formed at the end on the base side of said motor housing, and 
 said motor housing is fixed to said base via said heat shutoff means.    
     
     
         16 . The vacuum pump according to  claim 14 , wherein said heat shutoff wall has a flange portion on the end face opposite to said motor housing, and 
 said motor housing is fixed to said base via said flange portion.    
     
     
         17 . The vacuum pump according to  claim 15 , wherein said heat shutoff wall has a flange portion on the end face opposite to said motor housing, and 
 said motor housing is fixed to said base via said flange portion.    
     
     
         18 . The vacuum pump according to  claim 10 , wherein said vacuum pump further comprises cooling means for cooling said motor housing.  
     
     
         19 . The vacuum pump according to  claim 18 , wherein said cooling means is a water cooled tube provided on said motor housing to circulate cooling water.  
     
     
         20 . The vacuum pump according to  claim 19 , wherein said water cooled tube is provided on said motor housing so that solder or a paste material for heat conduction is additionally provided.