Patent ID: 7784708
Filing Date: 2010-08-31
Classification: F02M

Abstract:
1. A fuel injection device, comprising: a cylindrical body including a front part and a rear part; a sleeve configured to fasten the front part to the rear part of the cylindrical body; a needle with a first end including a head acting as a valve on a seat borne by the front part of the cylindrical body; an electroactive material actuator comprising a rod and configured to cause the head to move to open the valve, the actuator being positioned in the rear part of the cylindrical body; a weight extending from the rod; and a preloading device to keep the needle and the weight pressed against opposite ends of the rod; wherein the needle runs coaxially with respect to the cylindrical body in a form of a bar, the needle configured to go into axial resonance when subjected by the actuator to axial impulses at a given excitation frequency, thus superimposing vibrational movement of the head on an overall movement of the needle.