Valving system for infusion cassette

A system for actuating a valve, the system comprising:

• a base portion;
• a shaft extending from the base portion and configured to extend through a surface of a cassette recess of an infusion pump system to operate a valve in a fluid passageway of a cassette mounted in the cassette recess;
• a spring disposed on the shaft and extending along a portion of the shaft, wherein the spring is configured to be disposed interior to the surface;
• a rotatable member disposed on the base portion;
• and a cam structure configured to periodically bear against the rotatable member to cause movement of the shaft in a direction substantially parallel to the shaft, wherein the cam structure comprises a rotating cam having a protrusion or eccentricity that is configured to slide against the rotatable member to cause linear movement of the shaft in the direction substantially parallel to the shaft.

A method of operating an infusion pump system, comprising:

• providing a pump cassette in a cassette recess of the infusion pump system;
• and operating a valve of a controllable fluid passageway in the pump cassette by actuating a valve actuator that extends through a back surface of the cassette recess to contact a membrane of the pump cassette, wherein the valve actuator comprises:
• a base portion;
• a shaft extending from the base portion through the back surface;
• a spring disposed on the shaft and extending along a portion of the shaft, wherein the spring is disposed interior to the back surface;
• and a rotatable member disposed on the base portion, wherein operating the valve comprises periodically bearing against the rotatable member of the valve actuator with a cam structure to actuate the valve actuator in a direction substantially parallel to the shaft, wherein periodically bearing against the rotatable member comprises sliding against the rotatable member with a protrusion or eccentricity of a rotating cam of the cam structure to cause linear movement of the valve actuator in the direction substantially parallel to the shaft.