Patent ID: 7781937

Claim:
A device for producing electric energy comprising: a first piezo element converting mechanical energy into electric energy, the level of the electric energy being variable according to the variations of the mechanical energy; a controller block connected to the first piezo element for providing measurement data on the basis of the electric energy produced by the first piezo element; a detector block to examine the electric energy produced by the first piezo element to determine the moment of a triggering point on the basis of the level of the electric energy produced by the first piezo element; a second piezo element on the same substrate with the first piezo element converting mechanical energy into electric energy, the level of the electric energy being variable according to the variations of the mechanical energy; and a first energy storage unit for storing electric energy produced by the first element and for providing the electric energy for the operation of the controller block; wherein the control block comprises a controlling unit for controlling the voltage conversion to convert electric energy produced by the second piezo element when the triggering point is detected.