Peristaltic pump having a spiral cam and straight peristaltic tube

A peristaltic pump comprising a central suction port, an annular discharge chamber surrounding said suction port in spaced relationship thereto, three peristaltic tubes extending outwardly from said suction port to said annular discharge chamber at angular intervals of approximately 120.degree., each of said tubes defining a lumen extending from a suction end to a discharge end of the tube, and a rotatable spiral cam engaging each of said tubes and closing the lumen thereof.

A method of peristaltically pumping a fluid comprising the steps of providing a source of fluid to be pumped, providing at least one peristaltic tube means defining a lumen extending from a suction end in fluid communication with said source to a discharge end of said tube means, engaging said tube means with an at least essentially planar, spiral cam to compress said tube means at at least one point along the length thereof to close its lumen and effecting relative rotational movement between said tube means and said cam to progressively advance the point of closure of the lumen in the direction of the discharge end of the tube means to pump fluid from said source through said tube means.