Hydraulic gravity ram pump

Abstract

A piston type pumping apparatus comprises a vertically oriented cylinder having a top and a bottom with a first passageway for liquid in the cylinder adjacent to the top thereof. There is a second passageway for liquid in the cylinder adjacent to the bottom thereof A piston is reciprocatingly mounted within the cylinder. A hollow piston rod is connected to the piston and extends slidably and sealingly through the bottom of the cylinder. There is a reload chamber below the cylinder, the piston rod extending slidably and sealingly into the reload chamber and having a third passageway for liquid communicating with the reload chamber. The piston rod has a smaller cross-sectional area within the reload chamber than the piston, whereby liquid in the cylinder acting downwardly on the piston exerts a greater force on the piston than liquid in the reload chamber acting against the piston rod. There is a first one-way valve located in the third passageway which permits liquid to flow from the reload chamber into the piston rod and prevents liquid from flowing from the piston rod into the reload chamber. A fourth passageway for liquid extends from the reload chamber to a source of liquid to be pumped. A second one-way valve in the fourth passageway permits liquid to flow from the source of liquid into the reload chamber and prevents liquid from flowing from the reload chamber towards the source of liquid. There is means for storing pressurized liquid connected to the second passageway for storing pressurized liquid displaced below the piston, as the piston moves downwardly, and to assist in raising the piston and, accordingly, liquid contained within the piston rod, to pump liquid upwardly and through the first passageway.

1 . A piston type pumping apparatus, comprising: 
 a vertically oriented cylinder having a top and a bottom;    a first passageway for liquid in the cylinder adjacent to the top thereof;    a second passageway for liquid in the cylinder adjacent to the bottom thereof;    a piston reciprocatingly mounted within the cylinder and having an area against which pressurized fluid acts in the direction of movement of the piston;    a hollow piston rod connected to the piston and extending slidably and sealingly through an aperture in the bottom of the cylinder;    a reload chamber below the cylinder, the piston rod extending slidably and sealingly into the reload chamber and having a third passageway for liquid communicating with the reload chamber, the piston rod having a smaller area within the reload chamber upon which pressurized fluid in the reload chamber acts in a direction of movement of the piston and piston rod compared to said area of the piston, whereby liquid in the cylinder acting downwardly on the piston exerts a greater force on the piston than liquid in the reload chamber acting against the piston rod;    a first one-way valve located in the third passageway which permits liquid to flow from the reload chamber into the piston rod and prevents liquid from flowing from the piston rod into the reload chamber;    a fourth passageway for liquid extending from the reload chamber to a source of liquid to be pumped;    a second one-way valve in the fourth passageway which permits liquid to flow from the source of liquid into the reload chamber and prevents liquid from flowing from the reload chamber towards the source of liquid; and    means for storing pressurized liquid connected to the second passageway for storing pressurized liquid displaced below the piston, as the piston moves downwardly, and to assist in raising the piston and, accordingly, liquid contained within the piston rod, to pump liquid upwardly and through the first passageway.    
   
   
       2 . The apparatus of  claim 1  wherein the means for storing pressurized liquid includes a body of liquid.  
   
   
       3 . The apparatus of  claim 2 , including a pump connected to the body of liquid for pumping liquid into the cylinder below the piston to raise the piston.  
   
   
       4 . The apparatus of  claim 3 , wherein the pump is a piston type pump.  
   
   
       5 . The apparatus as claimed in  claim 4 , wherein the pump is above the second passageway.  
   
   
       6 . The apparatus of  claim 3 , wherein the pump is a centrifugal pump.  
   
   
       7 . The apparatus of  claim 6 , including a sixth passageway for liquid adjacent to the bottom of the cylinder, a first conduit connecting the sixth passageway to the pump and a second conduit connecting the second passageway to the body of liquid.  
   
   
       8 . The apparatus of  claim 7 , wherein the body of liquid is a receiver.  
   
   
       9 . The apparatus of  claim 8 , including a pressure release valve adjacent to the second passageway in the second conduit.