Reciprocating pump

Abstract

A reciprocating pump including a sleeve comprising a first flow path element and a plunger receivable in the sleeve is provided. The plunger includes a fluid contact face and second flow path element in fluid communication with the fluid contact face. The sleeve and the fluid contact face define a compression chamber comprising an inlet and an outlet. The sleeve and the plunger are moveable relative to one another for adjusting overlap between the first flow path element and the second flow path element for diverting flow of fluid from the compression chamber and out of the second flow path element during a discharge stroke to control flow of fluid pumped out of the outlet.

1 . A reciprocating pump comprising: 
 (a) a sleeve comprising a first flow path element;    (b) a plunger receivable in the sleeve, the plunger comprising: 
 i. a fluid contact face and  
 ii. a second flow path element in fluid communication with the fluid contact face;  
 wherein the sleeve and the fluid contact face define a compression chamber comprising an inlet and an outlet;  
 and wherein the sleeve and the plunger are moveable relative to one another for adjusting overlap between the first flow path element and the second flow path element for diverting flow of fluid from the compression chamber and out of the second flow path element during a discharge stroke to control flow of fluid pumped out of the outlet.  
   
     
     
         2 . A reciprocating pump according to  claim 1 , wherein the sleeve comprises a sidewall, and the first flow path element comprises a control hole formed in the sidewall of the sleeve.  
     
     
         3 . A reciprocating pump according to  claim 2 , wherein the plunger comprises a sidewall, and the second flow path element comprises a channel formed in the sidewall of the plunger.  
     
     
         4 . A reciprocating pump according to  claim 1 , wherein the sleeve comprises a sidewall, and the first flow path element comprises a channel formed in the sidewall of the sleeve.  
     
     
         5 . A reciprocating pump according to  claim 4 , wherein the plunger comprises a sidewall, the second flow path element comprises a bore formed in the plunger, and a first end of the bore defines a control hole formed in the sidewall of the plunger.  
     
     
         6 . A reciprocating pump according to  claim 5 , wherein the sleeve and the plunger are rotatable relative to one another about a common axis for adjusting the overlap between the control hole and the channel.  
     
     
         7 . A reciprocating pump according to  claim 6 , wherein the overlap is adjustable between a range of no overlap, whereby no fluid is diverted away from the compression chamber, and complete overlap whereby fluid is completely diverted away from the compression chamber.  
     
     
         8 . A reciprocating pump according to  claim 7 , wherein the sleeve is rotatable.  
     
     
         9 . A reciprocating pump according to  claim 7 , wherein the plunger is rotatable.  
     
     
         10 . A reciprocating pump according to  claim 9 , wherein the channel is helical.  
     
     
         11 . A reciprocating pump according to  claim 3 , wherein the control hole is in fluid communication with an overflow chamber.  
     
     
         12 . A reciprocating pump according to  claim 6 , wherein the channel is in fluid communication with an overflow chamber.  
     
     
         13 . A reciprocating pump according to  claim 12 , wherein the overflow chamber is in fluid communication with a fluid port upstream of the inlet.  
     
     
         14 . A reciprocating pump according to  claim 13 , wherein the sleeve comprises a hollow cylinder with an opening for receiving the plunger.  
     
     
         15 . A reciprocating pump according to  claim 14 , wherein the plunger comprises a cylinder.  
     
     
         16 . A reciprocating pump according to  claim 15 , wherein the control hole is round.  
     
     
         17 . A reciprocating pump comprising: 
 (a) a sleeve comprising a sidewall, the sidewall comprising a control hole;    (b) a plunger receivable in the sleeve, the plunger comprising: 
 i. a fluid contact face and  
 ii. a helical channel in fluid communication with the fluid contact face;  
 wherein the sleeve and the fluid contact face define a compression chamber comprising an inlet and an outlet;  
 and wherein the sleeve and the plunger are rotatable relative to one another about a common longitudinal axis to adjust the overlap between the control hole and the helical channel for diverting flow of fluid from the compression chamber and out of the control hole during a discharge stroke to control flow of fluid pumped out of the outlet.  
   
     
     
         18 . A reciprocating pump according to  claim 17 , wherein the sleeve is rotatable.  
     
     
         19 . A reciprocating pump according to  claim 18 , wherein the control hole is in fluid communication with an overflow chamber.  
     
     
         20 . A reciprocating pump according to  claim 19 , wherein the overflow chamber is in fluid communication with a fluid port upstream of the inlet.  
     
     
         21 . A reciprocating pump according to  claim 20 , wherein the sleeve comprises a hollow cylinder with an opening for receiving the plunger.  
     
     
         22 . A reciprocating pump according to  claim 21 , wherein the plunger comprises a cylinder.  
     
     
         23 . A reciprocating pump comprising: 
 (a) a sleeve comprising a sidewall, the sidewall comprising a helical channel;    (b) a plunger receivable in the sleeve, the plunger comprising: 
 i. a fluid contact face;  
 ii. a sidewall;  
 iii. a bore in fluid communication with the fluid contact face, a first end of the bore defining a control hole formed in the sidewall;  
 wherein the sleeve and the fluid contact face define a compression chamber comprising an inlet and an outlet;  
 and wherein the sleeve and the plunger are rotatable relative to one another about a common longitudinal axis to adjust the overlap between the control hole and the channel for diverting flow of fluid from the compression chamber and out of the control hole during a discharge stroke to control flow of fluid pumped out of the outlet.  
   
     
     
         24 . A reciprocating pump according to  claim 23 , wherein the sleeve is rotatable.  
     
     
         25 . A reciprocating pump according to  claim 24 , wherein the helical channel is in fluid communication with an overflow chamber.  
     
     
         26 . A reciprocating pump according to  claim 25 , wherein the overflow chamber is in fluid communication with a fluid port upstream of the inlet.  
     
     
         27 . A reciprocating pump according to  claim 26 , wherein the sleeve comprises a hollow cylinder with an opening for receiving the plunger.  
     
     
         28 . A reciprocating pump according to  claim 27 , wherein the plunger comprises a cylinder.  
     
     
         29 . A reciprocating pump comprising: 
 (a) a sleeve;    (b) a plunger receivable in the sleeve, the plunger comprising a fluid contact face, wherein the sleeve and the fluid contact face define a compression chamber comprising an inlet and an outlet;    (c) an accumulator in fluid communication with the compression chamber for diverting flow of fluid away from the compression chamber during a discharge stroke to control flow of fluid pumped out of the output, the accumulator comprising: 
 i. a housing;  
 ii. a control element slidingly receivable in the housing, the control element comprising a fluid contact face, the fluid contact face and the housing defining an accumulation chamber;  
 iii. a moveable stop configured to adjustably define a maximum volume of fluid diverted to the accumulation chamber by restricting movement of the control element; and  
 iv. a force means biasing the control element away from the moveable stop.  
   
     
     
         30 . A reciprocating pump according to  claim 29  wherein the housing comprises a hydraulic cylinder.  
     
     
         31 . A reciprocating pump according to  claim 30  wherein the control element comprises a piston, and a travel of the piston is adjustably restricted by the moveable stop.  
     
     
         32 . A reciprocating pump according to  claim 31  wherein a first pressure exerted by the force means is less than a second pressure sufficient to pump fluid out of the outlet.  
     
     
         33 . A reciprocating pump according to  claim 32  wherein the force means comprises a spring.  
     
     
         34 . A reciprocating pump according to  claim 33  wherein the spring comprises a compression spring.  
     
     
         35 . A reciprocating pump according to  claim 32  wherein the force means comprises a source of fluid pressure.  
     
     
         36 . A reciprocating pump according to  claim 35  wherein the fluid pressure is air pressure.  
     
     
         37 . A reciprocating pump according to  claim 31  wherein the moveable stop comprises an annular ring disposed in the housing, wherein the travel of the piston is restricted by abutment of a bearing surface of the piston against the annular ring.  
     
     
         38 . A method of controlling flow of fluid pumped by a reciprocating pump during a discharge stroke, the method comprising: 
 (a) providing a reciprocating pump comprising a sleeve and a plunger receivable in the sleeve, the sleeve comprising a first flow path element, the plunger comprising a face and a second flow path element in fluid communication with the face, wherein the sleeve and the face define a compression chamber comprising an inlet and an outlet, and the sleeve and the plunger are rotatable along a common axis relative to one another; and    (b) rotatably adjusting overlap between the first flow path element and the second flow path element to divert flow of fluid from the compression chamber and out of the control hole.    
     
     
         39 . A method according to  claim 38  wherein step (b) comprises rotating the sleeve.  
     
     
         40 . A method according to  claim 38  wherein step (b) comprises rotating the plunger.  
     
     
         41 . A method according to  claim 40  further comprising: 
 (c) allowing fluid flowing out of the second flow path element to flow to an overflow chamber.  
 
     
     
         42 . A method according to aspect  claim 41  further comprising: 
 (d) allowing fluid from the overflow chamber to flow to a fluid port upstream of the inlet.  
 
     
     
         43 . A method of controlling flow of fluid pumped by a reciprocating pump during a discharge stroke, the method comprising: 
 (a) providing a reciprocating pump comprising a compression chamber and an accumulator in fluid communication with the compression chamber, the accumulator comprising: 
 i. a housing;  
 ii. a control element slidingly receivable in the housing, the control element comprising a fluid contact face, the fluid contact face and the housing defining an accumulation chamber; and  
 iii. a moveable stop configured to restrict movement of the control element to define a maximum volume of the accumulation chamber;  
   (b) moving the moveable stop to adjust the maximum volume of the accumulation chamber to control a volume of fluid diverted from the compression chamber to the accumulation chamber.    
     
     
         44 . A method according to  claim 43  wherein step (a) comprises providing a force means to bias the control element away from the moveable stop.  
     
     
         45 . A method according to  claim 44  wherein step (a) comprises maintaining a first pressure exerted by the force means to be less than a second pressure sufficient to pump fluid out of an outlet of the reciprocating pump.