Patent ID: 7553294

Claim:
An injector system for injecting fluid from at least one syringe mounted thereon, the syringe having a plunger slidably disposed therein, the injector system comprising: a housing; at least one drive member at least partially disposed within the housing and operable to engage the plunger of the syringe; a controller in operative connection with the drive member; at least one syringe retaining mechanism associated with the housing, the syringe retaining mechanism adapted to releasably engage the syringe; and a first sensing pin positioned at a forward end of the drive member and extending forward of a forward surface of the drive member to sense contact of the first sensing pin with an inner surface the syringe plunger upon forward advancement of the drive member to engage the syringe plunger prior to contact of the forward surface of the drive member with the syringe plunger, the first sensing pin being forced rearward upon with contact with the inner surface of the syringe plunger without causing forward movement of the syringe plunger, the rearward motion of the first sensing pin causing data of proximity of the inner surface of the syringe plunger and the forward surface of the drive member to be transmitted to the controller before contact of the forward surface of the drive member with the inner surface of the syringe plunger to control forward advancement of the drive member, wherein the forward surface of the drive member is shaped to conform to the inner surface of the plunger.