Peristaltic pump with mechanism for maintaining linear flow.

摘要

A linear peristaltic pump (10) includes a mechanism for maintaining linear flow of fluid through an IV tube. The mechanism comprises a casing (22) carrying a rotatable camshaft (38) having a plurality of cams spaced therealong in helical arrangement and a plurality of fingers (30) coupled to the camshaft. A housing (24) for establishing linear reciprocal movement of the fingers in response to rotation of the shaft establishes a moving zone of occlusion along a tube (16) held against the fingers. Aligning means are included for establishing an axis or rotation of the camshaft which is slightly tilted with respect to the tube. This is accomplished by raising or lowering the upstream or the downstream end of the camshaft to prevent unwanted pressure from building up in the tube to reduce pulsatile flow and maintain linear flow. The aligning mechanism comprises a generally cylindrical bushing (60) having an eccentric hole therethrough for carrying the hinged connection between the casing and the housing. The bushing has a slot (65) therethrough for adjustably rotating the bushing for adjusting the amount of tilt. The adjustment can take place during operation of the pump, having a pressure sensor (50) against the tube, to achieve the optimal positioning of the camshaft depending on the tolerances of the pump mechanism (18) to establish linear flow of fluid through the tube.