Fuel injector with rate shaping control through piezoelectric nozzle lift
AssigneeCaterpillar Inc.
InventorsRonald D. Shinogle, Senthilkumar Rajagopalan
Life of this patent
Estimating the term…
Abstract
A fuel injector includes an injector body that defines a nozzle outlet. A needle valve member is mounted in the injector body and moveable a lift distance between an open position in which the nozzle outlet is open, and a closed position in which the nozzle outlet is blocked. A piezoelectric actuator is mounted in the injector body and is moveable a piezo distance between an off position and an on position. A coupling linkage interconnects the needle valve member to the piezoelectric actuator such that a movement of the piezoelectric actuator is multiplied into a larger movement of the needle valve member.
Claims19
A fuel injector including:
- an injector body defining a nozzle outlet;
- a needle valve member mounted in said injector body and being movable a lift distance between an open position in which said nozzle outlet is open, and a closed position in which said nozzle outlet is blocked;
- a piezoelectric actuator mounted in said injector body and being movable a piezo distance between an off position and an on position;
- a coupling linkage interconnecting said needle valve member to said piezoelectric actuator, and said coupling linkage multiplying movement of said piezoelectric actuator into a larger movement of said needle valve member;
- said needle valve member being stoppable at a plurality of different partially open positions between said open position and said closed position;
- and
- said coupling linkage including said needle valve member having a closing hydraulic surface.
A fuel injector including:
- an injector body defining a nozzle outlet;
- a needle valve member movably mounted in said injector body;
- a piezoelectric actuator movably mounted in said injector body;
- a coupling linkage interconnecting said needle valve member to said piezoelectric actuator, and said coupling linkage multiplying movement of said piezoelectric actuator into a larger movement of said needle valve member;
- a flow area past said needle valve member to said nozzle outlet being a function of a voltage applied to said piezoelectric actuator;
- and
- said coupling linkage including said needle valve member having a closing hydraulic surface.
A fuel injector including:
- an injector body defining a nozzle outlet;
- a needle valve member movably mounted in said injector body;
- a piezoelectric actuator movably mounted in said injector body;
- a coupling linkage interconnecting said needle valve member to said piezoelectric actuator, and said coupling linkage multiplying movement of said piezoelectric actuator into a larger movement of said needle valve member, and said coupling linkage including said injector body defining a needle control chamber;
- and
- said needle valve member including a closing hydraulic surface exposed to fluid pressure in said needle control chamber;
- and
- a flow area past said needle valve member to said nozzle outlet being a function of a voltage applied to said piezoelectric actuator.
Dependencies are inferred from the claim text.