Abstract: The present invention provides a method of manufacturing piezoelectric transducers that improves performance by reducing the mechanical losses in the component interfaces. The method involves the epoxy impregnation and encapsulation of the components within the piezoelectric stack assembly. Impregnation is achieved by capillary action that results in a chemical bond. The encapsulation method results in an epoxy conformal coating that provides a high degree of protection from harsh operational environments and reduces the risk of high voltage electric breakdown.

Abstract: The present invention relates to methods for velocity control of transducers that can compensate both for age related changes as well as the more immediate changes that occur during operation. In one aspect of the invention, the non-motional reactive current is measured at two predetermined frequencies, one below (Ilf) and one above the resonance frequency (Ihf). A correction factor is calculated from these measured currents is used to maintain a specified value of end effector velocity or displacement. In another aspect of the invention, methods are provided for the detection of secondary resonances that could be indicative of end effector fault conditions. In another aspect of the invention, velocity control is achieved.

Abstract: The present invention provides for single use ultrasonic transducers for use in surgical and dental applications. Specifically, the invention provides transducers comprising one or more of the following features, an active piezo ceramic material that contains less than 2% lead; piezo materials with a low Curie temperature, a high compressive bias force applied to the piezo ceramic elements, a bias bolt sub-assembly that includes a component assembled with a low-temperature glass-transition point filled epoxy material, and/or a permanently attached end effector with a self-locking taper.