Bi-directional bilge pump

Abstract

A pump with an outer housing defining an enclosure, an inlet for admitting fluid into the outer housing and an outlet for expelling fluid from the outer housing, a piston for selectively modulating a first fluid pressure, such that the first fluid pressure is associated with a location proximate the inlet, and a member that selectively isolates a second pressure associated with a location proximate the outlet from the first fluid pressure. The pump may also include a first chamber within the outer housing for receiving fluid admitted into the pump from an ambient environment and through an inlet to the pump, a second chamber within the outer housing for receiving fluid from the first chamber, and a piston that both (i) selectively controls the flow of fluid from the first chamber to the second chamber and (ii) selectively expels the fluid from the second chamber into the ambient environment.

What is claimed is: 
     
         1 . A pump comprising:
 (a) an outer housing defining an enclosure;   (b) an inlet for admitting fluid into a first chamber of said outer housing and an outlet for expelling fluid from a second chamber of said outer housing;   (c) a plunger, said plunger selectively isolating said first chamber from said second chamber by operating a ball of a valve having a length defined along the direction of flow of fluid through the valve, the plunger capable of a first directional movement and a second directional movement different than the first directional movement, where said fluid is admitted into said first chamber and expelled from said second chamber and out of the pump during said first directional movement, and said fluid is expelled from said second chamber and out of the pump, but not admitted into said first chamber during said second directional movement; where   (d) the ball is laterally retained over a major portion of its length by at least two support members of the valve and spaced from each other to thereby define an outlet of the valve, where the ball has a diameter that extends beyond the outlet.   
     
     
         2 . The pump of  claim 1 , wherein said inlet includes a primary check valve. 
     
     
         3 . The pump of  claim 1 , wherein the volume of said second chamber is approximately half of the volume of said first chamber. 
     
     
         4 . The pump of  claim 1 , wherein said plunger isolates a first fluid pressure associated with a location proximate to said inlet. 
     
     
         5 . The pump of  claim 1 , wherein said plunger isolates a second fluid pressure associated with a location proximate said outlet.