Patent ID: 8549840

Claim:
A fluid injector assembly comprising: an injector body having a distal end and a proximal end; a fluid inlet disposed towards the proximal end of the injector body; a fluid outlet disposed towards the distal end of the injector body; a fluid pathway extending between the inlet and the outlet; a needle rotatably disposed at least partially in the injector body and being moveable between an open and closed position, the needle having a tip at a proximal end thereof, the tip being configured to sealably close the fluid outlet; a first threaded region that cooperates with a corresponding threaded region on the needle; and first and second cooperating coupling members arranged axially of the needle, the first coupling member being attached to a motor, and the second coupling member being attached to a distal end of needle, wherein at least one of the coupling members includes at least one connecting member that is slidingly inserted into a corresponding cavity on the other coupling member, wherein rotation of the first coupling member by the motor also rotates the second coupling member and the needle, which in turn causes the threaded region of the needle to be threaded through the first threaded region so that the needle is rotably driven between the opened and closed positions, and wherein driving of the needle causes the at least one connecting member to slide in or out of the corresponding cavity.