Piston-type water pump

Abstract

A pump apparatus is provided comprising: a housing; a water chamber in the housing; an hydraulic chamber in the housing; a rod member extending at least partially into each of the water chamber and the hydraulic chamber; a first piston member mounted on the rod member and contained within the hydraulic chamber; a second piston member mounted on the rod member and contained within the water chamber; hydraulic means for alternatively forcing the first piston member in first and second directions; fluid inlet means extending through the housing adjacent an end of the water chamber; and fluid outlet means extending through the housing adjacent the end of the water chamber; wherein when the hydraulic means force the first piston member to move in the first direction, the second piston member is forced to move in the first direction, and fluid is drawn through the fluid inlet means into the water chamber; and wherein when the hydraulic means force the first piston member to move in the second direction, the second piston member is forced to move in the second direction, and fluid is forced through the fluid outlet means.

1 . A pump apparatus comprising: 
 a housing;    a water chamber in the housing;    an hydraulic chamber in the housing;    a rod member extending at least partially into each of the water chamber and the hydraulic chamber;    a first piston member mounted on the rod member and contained within the hydraulic chamber;    a second piston member mounted on the rod member and contained within the water chamber;    hydraulic means for alternatively forcing the first piston member in first and second directions;    fluid inlet means extending through the housing adjacent an end of the water chamber; and    fluid outlet means extending through the housing adjacent the end of the water chamber;    wherein when the hydraulic means force the first piston member to move in the first direction, the second piston member is forced to move in the first direction, and fluid is drawn through the fluid inlet means into the water chamber; and    wherein when the hydraulic means force the first piston member to move in the second direction, the second piston member is forced to move in the second direction, and fluid is forced through the fluid outlet means.    
   
   
       2 . The pump apparatus of  claim 1  wherein the hydraulic means comprise: 
 a first hydraulic tube in fluid communication with the interior of the hydraulic chamber on a first side of the first piston member; and    a second hydraulic tube in fluid communication with the interior of the hydraulic chamber on a second, opposite side of the first piston member;    wherein when hydraulic fluid is forced through the first hydraulic tube, the first piston member is forced to move in the first direction; and    wherein when hydraulic fluid is forced through the second hydraulic tube, the first piston member is forced to move in the second direction.    
   
   
       3 . The pump apparatus of  claim 1  wherein the fluid outlet means comprise a fluid exhaust passage within the housing.  
   
   
       4 . The pump apparatus of  claim 1  wherein the fluid inlet means and fluid outlet means comprise check valves to control fluid flow.  
   
   
       5 . The pump apparatus of  claim 1  wherein the fluid inlet means comprise an aperture opening in a downstream direction, such that when the fluid is drawn through the fluid inlet means into the water chamber, the fluid is drawn in an upstream direction to avoid undue fines and gas build-up in the fluid inlet means.