Syringe Plunger Engagement Mechanism

A fluid injector system has at least one reciprocally operable piston having a piston head, and a plunger engagement mechanism associated with the piston head. The plunger engagement mechanism has a cam sleeve disposed within the piston head and movable relative to the piston head, the cam sleeve having one or more tracks defining a cam surface. The plunger engagement mechanism further has an actuator operatively connected to the cam sleeve for moving the cam sleeve relative to the piston head, and one or more pins disposed within the cam sleeve. The one or more pins are movable within the one or more tracks with movement of the cam sleeve between a first or withdrawn position, wherein the one or more pins are radially withdrawn into the piston head and a second or extended position, wherein the one or more pins protrude radially outward relative to an outer surface of the piston head.