| 摘要 |
According to the present invention, a piezo actuator comprises a fixing part, a piezo, a vibration plate, a weight, and a frequency control part. The fixing part provides an inner space having a predetermined size. The piezo is arranged in an interior space of the fixing part and is contracted and is expanded by applied voltage. The vibration plate allows an end of one side thereof in a longitudinal direction to be fixed to a part of the fixing part and is coupled to the piezo to generate vibration due to contraction and expansion of the piezo. The weight is coupled to a weight fixing part formed on an end of the other side of the vibration plate to amplify vibration generated by the vibration plate. The frequency control part is positioned on a part of the vibration plate, which is not in contact with the piezo. Resonant frequency of the piezo actuator is controlled by changing a spring constant of the vibration plate or a weight of the weight to correspond to a frequency range of a device used in the piezo actuator, thereby securing optimum vibration force. Moreover, an external electrode capable of being provided with power from the outside is included in the exterior of the fixing part to allow a surface mounting technology to be applied or to be in contact with a spring electrode to electrically be connected. Accordingly, the piezo actuator is electrically connected simultaneously when the piezo actuator is assembled, and an automation process is allowed, thereby simplifying an assembling process. Thus, the piezo actuator can maximize the vibration force in a very small space, allow the amount of consumed current to be significantly reduced, can minimize electromagnetic noise, and can simplify an assembling process. |
