Motion coupler for a piezoelectric actuator

A fuel injector, comprising:

• a casing substantially aligned along a central axis of the fuel injector;
• a piezoelectric element disposed within the casing and configured to expand a first distance along the central axis;
• a control element disposed along the central axis, the control element configured to move a second distance and affect a flow of fuel through the fuel injector, the second distance not equal to the first distance;
• and
• a piston slidably disposed between the piezoelectric element and the control element, the piston configured to transfer motion from the piezoelectric element to the control element.

A method of injecting fuel, comprising:

• pressurizing fuel;
• selectively energizing a piezoelectric element to translate a first distance;
• absorbing a portion of the first distance and reducing shock within the piezoelectric element;
• and
• translating a piston a second distance to affect a flow of pressurized fuel to be injected, the second distance having a magnitude that is less than the magnitude of the first distance.

A power system, comprising:

• an engine;
• a pump fluidly connected to the engine and configured to pressurize fuel;
• a fuel injector disposed between the pump and the engine, the fuel injector configured to receive a pressurized fuel from the pump and to deliver an injection of the pressurized fuel to the engine;
• a piezoelectric element disposed within the fuel injector and movable a first distance;
• and
• a motion coupler coupled to the piezoelectric element, the motion coupler configured to move a second distance, the second distance having a magnitude less than the magnitude of the first distance.