A cantilever-mounted piezoelectric bender includes apparatus for forcing the bender to approach straightness when in a blocked position, e.g. when meeting a contact in an electrical relay. As a result, the potential energy recoverable from the bender is maximized without requiring additional piezoelectric material. A first preferred embodiment comprises a bender extension mounted on the free end of the bender. A normal load force is applied to the free end of the extension, rather than the free end of the bender, resulting in the application of a moment to the end of the bender which tends to straighten the bender when in a blocked position. A second preferred embodiment comprises a back-up plate disposed adjacent one surface of the bender. The degree to which the bender is straightened in a blocked position depends on the location of the point of tangency between the back-up plate and the extension.
A flexural actuator is fitted with an actuator means, the flexural actuator being fitted at its functional section with a sensor means for determination of the longitudinal stretch. This sensor means is placed at a position, and/or is placed in the longitudinal direction symmetrically on either side of such position, at which there is a constant longitudinal stretch independent from the setting force when the functional section is thrusting against a resistance.
A dicing tape attaching unit that can attach both a pre-cut dicing tape and a general dicing tape to a wafer in a semiconductor package assembling process, and an in-line system used in a semiconductor package process including the dicing tape attaching unit are provided. The dicing tape attaching unit supplies one of the pre-cut dicing tape and the general dicing tape and attaches it to a wafer according to the direction of rotation of a tape loader. Accordingly, without an additional pre-cut dicing tape attaching unit, either of the pre-cut dicing tape and the general dicing tape can be attached to the back side of the wafer by one and the same unit.
An electronic device (100) includes a housing (222) and a piezo-bender (400). The piezo-bender (400) includes a metal beam (402) having at least a portion of a surface mechanically coupled to a piezo-ceramic layer (304). The piezo-bender (400) is flexibly coupled to the housing (222) at an end of the metal beam (402) forming a cantilever structure. A vibratable body (404) is mechanically coupled to the other end of the metal beam (402). A tuning slide (604) is slidably coupled to the piezo-bender (400) for mechanically tuning the resonant frequency of vibration of the piezo-bender (400) by varying the length of the piezo-bender (400) that can vibrate. An electrical drive circuit (708) is electrically coupled to the piezo-bender (400) for electrically driving the piezo-bender (400) with a drive signal to generate vibratory motion in the piezo-bender (400) for providing a vibratory alert.
A low frequency flex-beam underwater acoustic transducer has a base, a flexible beam having one end cantilever mounted on the base, and piezoelectric driving means, for flexurally driving the beam. The piezoelectric driving means operates in the k.sub.31 and/or the k.sub.33 mode.
A piezoelectric actuator, which has a large displacement rate and a relatively simple structure, is capable of providing an output without the need for a specific support and can be manufactured at low costs, is provided. The piezoelectric actuator 10 takes a planar plate-like form and has first and second layer regions 11 and 12 lying one upon the other. The first layer region 11 is formed comprising a piezoelectric ceramic material and contains electrodes 13-1 to 13-n for receiving an actuation voltage to cause this first layer region to contract in a plane parallel thereto. The second layer region 12 is formed integrally with the first layer region 11 and comprises a ceramic material.
