Pump for liquids

Claim 2

A pump for liquids comprising: a. a pump body having upper and lower inlets arranged one above the other, and an outlet, b. top and bottom walls within said body defining an impeller chamber communicating with said inlets and outlet, said lower inlet being in said bottom wall and said top wall having an opening communicating with said upper inlet, c. an impeller shaft extending into said body through said opening, d. means for rotating said shaft, and e. an upper and a lower impeller fixed to and rotatable with said shaft, said impellers being located within said chamber between said two inlets, said outlet being between said lower impeller and said bottom wall, said lower and upper impellers when rotated drawing liquid in through said lower and upper inlets, respectively, moving the liquid in opposite directions through said chamber, and discharging thE liquid through said outlet, whereby said upper impeller serves to both move liquid from said upper inlet to said outlet and prevent flow of liquid from said chamber upwardly along said shaft.

Claim 3

A pump as defined in claim 1, including a filter communicating with said outlet.

Claim 4

A pump as defined in claim 1, including an annular float surrounding the portion of said pump body having the upper of said inlets, surface liquid flowing over said float to said upper inlet.

Claim 5

A pump as defined in claim 1, wherein said pump body is formed of two telescoping parts, one of said inlets being formed in each of said parts, the inner of said parts being movable into the outer of said parts to close one of said inlets.

Claim 6

A pump as defined in claim 1, wherein the upper of said impellers is spaced closer to said top wall than the spacing between the lower impeller and said bottom wall.

Claim 7

A pump as defined in claim 5, wherein the upper of said inlets is located above said top wall, said upper inlet communicating with said chamber via said opening.

Claim 8

A pump for liquids comprising: a. a pump body having an inlet and an outlet; b. first and second walls within said body defining an impeller chamber communicating with said inlet and outlet, said inlet being in said first wall, c. an impeller shaft extending into said chamber through an opening in said second wall, d. means for rotating said shaft, and e. first and second independent impellers within said chamber and fixed to and rotatable with said shaft, said impellers being spaced apart along the length of said shaft, said first impeller being spaced relatively far from said first wall but said first impeller being closer to both said inlet and outlet than said second impeller and serving to draw liquid through said inlet and discharge liquid through said outlet, said impellers being arranged so that most of the liquid moves through only said first impeller as it flows from said inlet to said outlet and said second impeller being spaced relatively close to said second wall and urging liquid toward said outlet in a direction opposite to the direction in which said first impeller moves liquid, thereby preventing any liquid from moving through said opening from said chamber, the space between said impellers being filled with liquid which serves to prevent air, entering said chamber through said opening, from reaching said outlet.

Claim 9

A pump for liquids comprising: a. a pump body having an inlet and an outlet; b. first and second walls within said body defining an impeller chamber communicating with said inlet and outlet, said inlet being in said first wall, c. an impeller shaft extending into said chamber through an opening in said second wall, d. means for rotating said shaft, and e. first and second independent impellers within said chamber and fixed to and rotatable with said shaft, said impellers being spaced apart along the length of said shaft, said first impeller being spaced relatively far from said first wall but said first impeller being closer to both said inlet and outlet than said second impeller and serving to draw liquid through said inlet and discharge liquid through said outlet, said impellers being arranged so that most of the liquid moves through only said first impeller as it flows from said inlet to said outlet and said second impeller being spaced relatively close to said second wall and urging liquid toward said outlet in a direction opposite to the direction in which said first impeller moves liquid, thereby preventing any liquid from moving through said opening from said chamber, the space between said impellers being filled with liquid which serves to prevent air, entering said chamber through said opening, from reaching said outlet.