Vacuum pump

Abstract

A vacuum pump has a main pump, a booster pump and a coupling member. The main pump has a first housing and a first pump mechanism accommodated in the first housing. The booster pump has a second housing and a second pump mechanism accommodated in the second housing. The booster pump and the main pump are coupled in series such that gas is sent from the booster pump to the main pump. The coupling member couples the first housing and the second housing to each other. The coupling member is directly coupled to a portion of the first housing that surrounds a last stage of the first pump mechanism such that transmission of heat to the portion is permitted.

1 . A vacuum pump comprising: 
 a main pump, wherein the main pump has a first housing and a first pump mechanism accommodated in the first housing, the first pump mechanism being of a multi-stage type;    a booster pump, wherein the booster pump has a second housing and a second pump mechanism accommodated in the second housing, wherein the booster pump and the main pump are coupled in series such that gas is sent from the booster pump to the main pump; and    a coupling member for coupling the first housing and the second housing to each other, wherein the coupling member is directly coupled to a portion of the first housing that surrounds a last stage of the first pump mechanism such that transmission of heat to the portion is permitted.    
     
     
         2 . The vacuum pump according to  claim 1 , wherein the coupling member is integrally formed with at least one of the first housing and the second housing.  
     
     
         3 . The vacuum pump according to  claim 1 , wherein the coupling member is formed separately from the first housing, and wherein the coupling member abuts on an outer surface of the portion of the first housing that surrounds the last stage of the first pump mechanism.  
     
     
         4 . The vacuum pump according to  claim 3 , wherein a thermal-conductance improver is provided at the joint between the coupling member and the first housing.  
     
     
         5 . The vacuum pump according to  claim 4 , wherein the thermal-conductance improver is located between the coupling member and the first housing such that adhesion of the coupling member to the first housing is improved.  
     
     
         6 . The vacuum pump according to  claim 1 , wherein the coupling member supports one of the main pump and the booster pump such that the supported pump is located above the other pump.  
     
     
         7 . The vacuum pump according to  claim 1 , wherein the coupling member has a communication passage, wherein the communication passage connects a gas exhaust port of the booster pump to a gas suction port of the main pump.  
     
     
         8 . The vacuum pump according to  claim 1 , wherein the gas is a gaseous reaction product generated at a semiconductor machining apparatus.  
     
     
         9 . A vacuum pump comprising: 
 a main pump, wherein the main pump has a first housing and a first pump mechanism accommodated in the first housing, the first pump mechanism being of a multi-stage type;    a booster pump, wherein the booster pump has a second housing and a second pump mechanism accommodated in the second housing, wherein the booster pump and the main pump are coupled in series such that gas is sent from the booster pump to the main pump; and    a coupling member for coupling the first housing and the second housing to each other, wherein the coupling member has a first portion and a second portion, wherein the first portion forms a gas passage for guiding gas from the booster pump to a foremost stage of the first pump mechanism, and the second portion extends from a portion of the first housing that surrounds the foremost stage of the first pump mechanism to a portion of the first housing that surrounds a last stage of the first pump mechanism, and wherein the second portion is directly coupled to the portion of the first housing that surrounds the last stage of the first pump mechanism such that transmission of heat to the portion is permitted.    
     
     
         10 . The vacuum pump according to  claim 9 , wherein the second portion of the coupling member is integrally formed with the first housing.  
     
     
         11 . The vacuum pump according to  claim 9 , wherein the second portion of the coupling member is formed separately from the first housing, and wherein the second portion abuts on an outer surface of the portion of the first housing that surrounds the last stage of the first pump mechanism.  
     
     
         12 . The vacuum pump according to  claim 9 , wherein a thermal-conductance improver is provided at the joint between the coupling member and the first housing.  
     
     
         13 . The vacuum pump according to  claim 12 , wherein the thermal-conductance improver is located between the coupling member and the first housing such that adhesion of the coupling member to the first housing is improved.  
     
     
         14 . The vacuum pump according to  claim 9 , wherein the coupling member supports one of the main pump and the booster pump such that the supported pump is located above the other pump.  
     
     
         15 . The vacuum pump according to  claim 9 , wherein the gas is a gaseous reaction product generated at a semiconductor machining apparatus.