Patent ID: 6017202
Filing Date: 2000-01-25
Classification: F04C

Abstract:
A fluid pump comprising:a pump housing defining a pump inlet adapted to receive fluid from a fluid source and which is in communication with first and second inlet chambers, an outlet chamber in communication with a pump outlet, a first flow path in fluid communication with said first inlet chamber and said outlet chamber, a second flow path in fluid communication with said second inlet chamber and said outlet chamber, and a pump chamber in fluid communication with said first and second flow paths;a stator ring supported for rotation in said pump chamber and having an aperture defining a series of internal lobes;a pump ring supported for rotation in said aperture of said stator ring and having an outer peripheral surface defining a series of external lobes;a first inlet valve retained in said first inlet chamber for movement between a first position preventing fluid communication between said pump inlet and said first inlet chamber and a second position permitting fluid communication therebetween;a second inlet valve retained in said second inlet chamber for movement between a first position preventing fluid communication between said pump inlet and said second inlet chamber and a second position permitting fluid communication therebetween; andan outlet valve retained in said outlet chamber for movement between a first position and a second position, said outlet valve operable in its first position to inhibit fluid communication between said first flow path and said pump outlet while permitting fluid communication between said second flow path and said pump outlet, and said outlet valve is operable in its second position to inhibit fluid communication between said second flow path and said pump outlet while permitting fluid communication between said first flow path and said pump outlet;wherein rotation of said pump ring in a first direction relative to said pump housing generates a pumping action between said pump ring and said stator ring for drawing fluid into said pump inlet and causing said first inlet valve to move to its second position, said second inlet valve to move to its first position, and said outlet valve to move to its first position, and wherein rotation of said pump ring in a second direction relative to said pump housing generates a pumping action between said pump ring and said stator ring for drawing fluid into said pump inlet and causing said second inlet valve to move its second position, said first inlet valve to move its first position, and said outlet valve to move to its second position.