Patent ID: 7832656

Claim:
A fluid injector comprising: a housing, a valve body, and an actuator unit that is inserted into the housing, wherein the valve body comprises: a cartridge with a recess that takes in a needle, a hollow body, which is arranged in a fixed position to the needle and forms a first spring rest, a valve cap which takes in the cartridge and forms a second spring rest, a return spring, that rests on the first spring rest and on the second spring rest, a first axially extendable interface between the housing and the valve cap configured to allow axial extension at least during a calibration, a second axially extendable interface between the valve cap and the cartridge configured to allow axial extension at least during the calibration, a first seal maintained within the first axially extendable interface, and a second seal maintained within the second axially extendable interface, wherein the housing and the cartridge stay in a fixed position relative to each other during the calibration.