Patent ID: 8550310

Claim:
A pump assembly for use in pumping a viscous material through a pumping tube which can be engage by the pump assembly, the pump assembly comprising; a pump body; a rotor rotatably retained on the pump body; the rotor having a pair of plates for operatively retaining a plurality of rollers therebetween, the plates having generally rectangular shape and having rounded corners extending sufficiently to generally cover ends of the corresponding rollers retained between the plates and to support the rollers; a stator pivotably retained on the pump body; a lever arm operatively retained on the pump body; a cam assembly associated with the lever arm and the stator for use in engaging the stator to move the stator to an engaged position engaging a pumping tube between the rotor and the stator, and for use in disengaging the pumping tube from between the rotor and the stator; and the stator being pivotably retained on the pump body at a single pivot point and pivoting at that pivot point spaced from a rotation point of the rotor, the lever arm being movable relative to a fixed rotation axis on the pump body and spaced from the pivot point and the rotation point for engaging and disengaging the stator, the lever arm including a portion extending over a portion of the tube engaged between the stator and rotor in the engaged position.