Patent ID: 7578662

Claim:
A peristaltic roller pump comprising: a housing with an internal circular opening, said opening including a first half and a second half, a first elastic tubing section placed along and in contact with said first half of said circular opening, said first elastic tubing section having a first inlet and a first outlet, a second elastic tubing section placed along and in contact with said second half of said circular opening, said second elastic tubing section having a second inlet and a second outlet, said first outlet is not connected directly to said second inlet, and a rotor assembly including a rotor having a rotor center placed in the center of said circular opening, said rotor being driven by a shaft attached at said rotor center, said rotor also having a first arm and a second arm extending from said center in the opposite directions, said first arm carrying a freely rotating occluding roller, said second arm carrying a freely rotating pumping roller, said occluding roller comprising a central portion and a plurality of protrusions extending therefrom, said protrusions are spaced apart to allow a portion of said elastic tubing between adjacent protrusions to regain at least part of its non-compressed shape when compressed by said adjacent protrusions, whereby said roller pump is adapted for alternating pumping in two phases, a first phase defined by progressive squeezing of said first elastic tubing section by said pumping roller to cause flow therein from said first inlet to said first outlet and occluding of said second elastic tubing section by said occluding roller to prevent any flow therein from said second inlet to said second outlet, and a second phase defined by progressive squeezing of said second elastic tubing section by said pumping roller to cause flow therein from said second inlet to said second outlet and occluding of said first elastic tubing section by said occluding roller to prevent any flow therein from said first inlet to said first outlet.