Pump

Abstract

A pump.

1 . A pump comprising:
 a plurality of pump rotor housings, each having a work rotor and a sealing rotor that cooperate to compress fluid in the respective pump rotor housing between a first chamber and a second chamber;   at least one inlet to the pump and at least one outlet to the pump; and   at least one shaft that together drives the work rotor and sealing rotor.   
     
     
         2 . The pump of  claim 1  where each of the plurality of pump rotor housings are isolated from each other such that fluid that enters a first chamber of one of the plurality of pump rotor housings does not enter a first chamber of any other of the plurality of pump rotor housings. 
     
     
         3 . The pump of  claim 2  where each pump rotor housing has an inlet and an outlet different from those of any other pump rotor housing. 
     
     
         4 . The pump of  claim 1  where the second chamber of one of the plurality of pump rotor housings releases fluid into a first chamber of another one of the plurality of pump rotor housings. 
     
     
         5 . The pump of  claim 4  having a plurality of outlets that each exhaust compressed fluid that has not intermixed with compressed fluid exhausted from the other ones of the plurality of outlets. 
     
     
         6 . The pump of  claim 4  having a member interposed between the plurality of pump rotor housings that defines a path through which the fluid flows between the second chamber of one of the plurality of pump rotor housings and the first chamber of another one of the plurality of pump rotor housings, the path comprising an elongate portion and opposed first and second openings on either side of the elongate portion, the first opening receiving fluid from the second chamber and the second opening releasing fluid into the first chamber. 
     
     
         7 . The pump of  claim 1  where the work rotor includes a vane, and the sealing rotor includes a notch into which the vane engages during rotation of the sealing rotor and the work rotor, and where the vane is shaped to cause negative feedback on the entry of fluid into the notch as the vane released from the notch. 
     
     
         8 . The pump of  claim 1  including at least one seal, and where the pressure ratio of the pump seals improves the effectiveness of the at least one seal in containing pressurized fluid within the at least one pump rotor housing. 
     
     
         9 . The pump of  claim 1  includes a vane, and the sealing rotor includes a notch into which the vane engages during rotation of the sealing rotor and the work rotor, and where the vane and the notch have respective curved surfaces with the same radius of curvature. 
     
     
         10 . The pump of  claim 1  where the work rotor is housed in a cavity having generally cylindrical surface with a first radius of curvature and a second radius of curvature smaller than the first radius of curvature, and where the second radius of curvature of the cylindrical surface is limited to an area slightly offset from a centerline of the work rotor. 
     
     
         11 . A method of assembling a pump, the method comprising:
 (a) attaching a first rotor housing to a second rotor housing, each having a work rotor and a sealing rotor that cooperate to compress fluid in the respective pump rotor housing between a first chamber and a second chamber, where at least one of the first and second rotor housings has an inlet and at least one of the first and second rotor housings has an outlet;   (b) attaching end caps that surround the first rotor housing and the second rotor housing; and   (c) providing a drive system for the work rotor and the sealing rotor of each of the first rotor housing and the second rotor housing.   
     
     
         12 . The method of  claim 11  where each of the plurality of pump rotor housings are isolated from each other such that fluid that enters a first chamber of one of the plurality of pump rotor housings does not enter a first chamber of any other of the plurality of pump rotor housings. 
     
     
         13 . The method of  claim 12  where each pump rotor housing has an inlet and an outlet different from those of any other pump rotor housing. 
     
     
         14 . The method of  claim 11  where the second chamber of one of the plurality of pump rotor housings releases fluid into a first chamber of another one of the plurality of pump rotor housings. 
     
     
         15 . The method of  claim 14  having a plurality of outlets that each exhaust compressed fluid that has not intermixed with compressed fluid exhausted from the other ones of the plurality of outlets. 
     
     
         16 . The method of  claim 14  including the step of attaching the first rotor housing and the second rotor housing to respective sides of a wall member, the wall defining a path through which the fluid flows between the second chamber of one of the plurality of pump rotor housings and the first chamber of another one of the plurality of pump rotor housings, the path comprising an elongate portion and opposed first and second openings on either side of the elongate portion, the first opening receiving fluid from the second chamber and the second opening releasing fluid into the first chamber. 
     
     
         17 . A pump comprising:
 an inlet for providing fluid to the pump;   a rotatable sealing rotor defining a cavity; and   a rotatable work rotor defining a vane that engages with the cavity during rotation of the work rotor and the sealing rotor, the vane having a tip shaped to provide negative feedback on fluid entering the cavity as the vane clears the cavity.   
     
     
         18 . The pump of  claim 17  where the shape of the tip creates turbulence. 
     
     
         19 . The pump of  claim 17  where the tip is U-shaped. 
     
     
         20 . The pump of  claim 17  where the tip is V-shaped.