Patent ID: 8089197
Filing Date: 2012-01-03
Classification: F02D,H02N

Abstract:
1. A method for operating a piezoelectric element, the method comprising: applying a first voltage to the piezoelectric element to produce a first deflection of the piezoelectric element with a travel, wherein an electrical discharge of the piezoelectric element after applying the first voltage results in a first contraction of the piezoelectric element; after the first contraction, applying a second voltage to the piezoelectric element to cause a further contraction of the piezoelectric element, the second voltage having a polarity opposite that of the first voltage; and re-applying the first voltage after electrical discharge of the applied second voltage, wherein a deflection of the piezoelectric element has the same travel; wherein the piezoelectric element has a first dimension after the electrical discharge of the first voltage, and has a smaller second dimension after the electrical discharge of the second voltage; wherein the piezoelectric element has a third dimension after the further contraction, the third dimension being less than the first dimension and the second dimension; and wherein the second voltage has a lower absolute maximum value than the first voltage.