Compact injector drive

A method of pressurizing a fluid at a powered fluid injector, the method comprising the steps of:

• actuating a drive assembly of the powered fluid injector to supply a motive force for moving a tip of the drive assembly between a retracted position and an extended position, the tip being configured to be secured to a plunger that is within an internal volume of a reservoir, the motive force being transmitted to the tip by a telescoping member that comprises a first segment portion having a first diameter and a second segment portion having a second diameter that is greater than the first diameter, wherein the first segment portion extends out from a first nesting position within the second segment portion when the motive force is supplied;
• moving the tip from the retracted position to the extended position by moving a portion of the drive assembly from a first location to a second location;
• and
• moving the tip from the extended position to the retracted position by moving the portion of the drive assembly from the second location to the first location.

A powered fluid injector comprising:

• a sleeve configured to receive a reservoir that includes an inner reservoir diameter and a reservoir length L defining an internal reservoir volume and a plunger within the internal reservoir volume;
• a drive assembly configured to pressurize the internal reservoir volume, the drive assembly comprising:
• a tip having a central longitudinal axis and configured to be secured to the plunger, the tip having a retracted position and an extended position,
• an actuator configured to supply a motive force to the tip for moving the tip between the retracted position and the extended position, and
• a telescoping member configured to transmit the motive force from the actuator to the tip, the telescoping member comprising a first segment portion having a first diameter and a second segment portion having a second diameter that is greater than the first diameter, the first segment portion being configured to extend out from a first nesting position within the second segment portion when the actuator supplies the motive force;
• and
• a drive assembly housing having a housing length in a direction parallel to the central longitudinal axis, a housing width in a first direction perpendicular to the central longitudinal axis, and a housing height in a second direction perpendicular to the central longitudinal axis, wherein the actuator is positioned within the drive assembly housing, and wherein the first segment portion and the second segment portion are positioned within the drive assembly housing when the tip is in the retracted position, and
• wherein the housing length and the reservoir length L define a package length extending in the direction parallel to the central longitudinal axis and the package length is less than 2 L.