Patent ID: 9689359
Date: 2017-06-27
CPC Classifications: B05B,F02M

Claim:
1. A piezo injector, comprising: an injector body; an actuator chamber formed in the injector body; a piezo actuator comprising a fully active piezo stack arranged in the actuator chamber; a nozzle body downstream of the injector body; a control piston bore formed in the nozzle body, a control sleeve arranged in the control piston bore, a control piston arranged in the control sleeve, wherein a first face side of the control sleeve facing toward the piezo actuator sealingly adjoins an intermediate plate, wherein the control piston has a first face side, wherein the first face side of the control piston facing toward the piezo actuator and the first face side of the control sleeve facing toward the piezo actuator define a first control chamber, a nozzle needle with a second face side, wherein the nozzle needle is guided displaceably in a central, cylindrical bore in the control piston, wherein the central bore in the control piston and the second face side of the nozzle needle define a second control chamber, at least one connecting bore formed in the control piston and extending between the first control chamber and the second control chamber, to transmit a change in pressure between the first and the second control chamber, a leakage pin arranged between the piezo actuator and the first face side of the control piston in a leakage pin bore in the intermediate plate, the leakage pin configured to transmit an actuator stroke directly to the control piston, a spring chamber located at an end of the control piston and of the control sleeve facing away from the first control chamber and, a control sleeve spring arranged in the spring chamber, the control sleeve spring forcing the control sleeve into abutment against the intermediate plate.