Patent ID: 6923422

Claim:
A valve for controlling the flow of a fluid through a tube comprising: a valve body including a passage having a longitudinal axis and sized to receive the tube, and a cavity that opens into the passage and includes a closed end; a bar attached to the body and extending through the passage adjacent the longitudinal axis and opposite the cavity; a plunger movable within the cavity away from the bar to an open position where the fluid can flow through the tube, and toward the bar to a closed position where the plunger pinches a portion of the tube against the bar to prevent or substantially prevent the flow of fluid through the tube; a spring disposed within the cavity between the closed end and the plunger and operable to bias the plunger toward the bar; a spring adjustment plate disposed between the closed end of the cavity and the spring and movable within the cavity to adjust the spring compression when the plunger is in the closed position; and a spring adjustment member operable to move the spring adjustment plate.