Stator for a vacuum pump

Abstract

At least a part of a stator for a vacuum pump, comprising: a first wall and one or more sidewalls extending therefrom, the first wall and the one or more sidewalls define an internal cavity, and an outlet channel formed through a sidewall of the one or more sidewalls, the outlet channel having an opening at an internal surface of one or more of the sidewalls, the outlet channel being for allowing a fluid to flow from the internal cavity to an outside of the at least a part of the stator. The internal surface of the first wall is contiguous with the opening. Thus, liquid and particulate matter within the at least a part of a stator will tend to flow, due to gravity, out of the stator via the outlet channel.

1 . At least a part of a stator for a vacuum pump, comprising:
 a first wall;   one or more sidewalls extending upwards from the first wall, wherein the first wall and the one or more sidewalls define an internal cavity; and   an outlet channel formed through a sidewall of the one or more sidewalls, the outlet channel having an opening at an internal surface of the sidewall of the one or more sidewalls, the outlet channel being for allowing a fluid to flow from the internal cavity to an outside of the at least a part of the stator; wherein   an internal surface of the first wall is contiguous with the opening of the outlet channel.   
     
     
         2 . The at least a part of a stator for a vacuum pump according to  claim 1 , wherein a lowest point of the internal surface of the first wall is contiguous with the opening of the outlet channel. 
     
     
         3 . The at least a part of a stator for a vacuum pump according to  claim 1 , wherein the outlet channel extends from the opening of the outlet channel in a direction having a downwards-oriented component. 
     
     
         4 . The at least a part of a stator for a vacuum pump according to  claim 1 , wherein the internal surface of the first wall slopes towards the opening or is substantially flat. 
     
     
         5 . The at least a part of a stator for a vacuum pump according to  claim 1 , wherein the first wall comprises one or more through bores, each of the one or more through bores being for receiving a respective rotor shaft. 
     
     
         6 . The at least a part of a stator for a vacuum pump according to  claim 1 , wherein the first wall comprises an external surface opposite to the internal surface, the external surface of the first wall comprising one or more recesses. 
     
     
         7 . The at least a part of a stator for a vacuum pump according to  claim 6 , wherein the one or more recesses in the external surface of the first wall comprise one or more recesses selected from the group of recess consisting of a loop-shaped groove for receiving an O-ring and a recess configured to receive a thermally insulative spacer. 
     
     
         8 . A stator for a vacuum pump, comprising:
 a first stator part, the first stator part being a part of a stator according to  claim 1 ; and   a second stator part comprising:   a second wall; and   one or more further sidewalls extending downwards from the second wall; wherein   the one or more side walls of the first stator part are attached to the one or more further sidewalls of the second stator part such that the first wall, the one or more sidewalls, the second wall, and the one or more further sidewalls define an internal chamber; and   the stator further comprises an inlet channel formed through a sidewall of the one or more sidewalls or the one or more further sidewalls, the inlet channel being for allowing a fluid to flow into the internal chamber from the outside of the stator.   
     
     
         9 . The stator according to  claim 8 , wherein the second wall comprises one or more through bores, each of the one or more through bores being for receiving a respective rotor shaft. 
     
     
         10 . The stator according to  claim 8 , wherein the second wall comprises an external surface, the external surface of the second wall comprising one or more recesses. 
     
     
         11 . The stator according to  claim 10 , wherein the one or more recesses in the external surface of the second wall comprise one or more recesses selected from the group of recess consisting of a loop-shaped groove for receiving an O-ring and a recess configured to receive a thermally insulative spacer. 
     
     
         12 . The stator according to  claim 8 , wherein the stator further comprises a pressure relief valve disposed within either the first wall or the second wall. 
     
     
         13 . The stator according to  claim 12 , wherein:
 the stator further comprises a channel formed within either the first wall or the second wall;   the channel comprises a first opening at a first end of the channel and a second opening at a second end of the channel;   at least one of the first opening or the second opening of the channel is formed in an internal surface of either the first wall or the second wall; and   the pressure relief valve is disposed within the channel.   
     
     
         14 . A vacuum pump comprising:
 a stator according to  claim 8 ;   one or more rotor shafts extending through the internal chamber of the stator between the first wall and the second wall; and   one or more rotors, each rotor being mounted on a respective one of the rotor shafts.   
     
     
         15 . The vacuum pump of  claim 14 , wherein:
 the one or more rotors defines a suction side of the internal chamber and an exhaust side of the internal chamber;   the stator further comprises a channel formed within either the first wall or the second wall;   the channel comprises a first opening at a first end of the channel and a second opening at a second end of the channel;   the first opening of the channel is formed in an internal surface of either the first wall or the second wall at the exhaust side of the internal chamber;   the second opening of the channel is formed in the internal surface of either the first wall or the second wall at the suction side of the internal chamber; and   the vacuum pump further comprises a pressure relief valve disposed within the channel.   
     
     
         16 . The vacuum pump of  claim 14 , wherein
 the first wall comprises an external surface, the external surface of the first wall comprising one or more recesses formed therein;   the vacuum pump further comprises:   a first O-ring and/or a first thermally insulative spacer disposed within the one or more recesses formed in the external surface of the first wall; and   a first headplate for supporting the one or more rotor shafts, the first headplate being disposed facing the external surface of the first wall and against the first O-ring and/or the first thermally insulative spacer such that the first headplate is spaced apart from the external surface of the first wall.   
     
     
         17 . The vacuum pump of  claim 14 , wherein
 the second wall comprises an external surface, the external surface of the second wall comprising one or more recesses formed therein;   the vacuum pump further comprises:   a second O-ring and/or a second thermally insulative spacer disposed within the one or more recesses formed in the external surface of the second wall; and   a second headplate for supporting the one or more rotor shafts, the second headplate being disposed facing the external surface of the second wall and against the second O-ring and/or the second thermally insulative spacer such that the second headplate is spaced apart from the external surface of the second wall.