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 The one or more pins are movable within the oneor more tracks with movement of the cam sleeve between a first or withdrawn position, wherein the one or more pins are radially withdrawn into the piston head and a second or extended position, wherein the one or more pins protrude radially outward relative to an outer surface of the piston head. 流体注入器系统具有带有活塞头的至少一个可往复操作的活塞，以及与活塞头相关联的柱塞接合机构。柱塞接合机构具有凸轮套筒，凸轮套筒设置在活塞头内且相对于活塞头可移动，凸轮套筒具有限定凸轮表面的一个或多个轨道。柱塞接合机构还具有致动器以及设置在凸轮套筒内的一个