Patent ID: 8675287

Claim:
A piezoelectric driving module for lens, defining a photographic optical axis and comprising: a housing having a receiving space therein; a driven object received in the receiving space; at least a piezo member provided on the housing and adjacent to a first lateral surface of the driven object; a rubbing element provided on the housing and adjacent to a second lateral surface of the driven object, wherein the second lateral surface may or may not coincide with the first lateral surface, and the photographic optical axis is parallel to the first lateral surface and the second lateral surface; wherein when a voltage is applied to the at least a piezo member, the at least a piezo member drives the driven object to move along the photographic optical axis such that a predetermined frictional force is generated between the rubbing element and the driven object to reduce a speed difference of the driven object that results from a force of gravity acting on the driven object while the driven object is moved; a pre-pressing element provided on the housing so as to apply a pre-pressing force to the at least a piezo member and thereby keep the at least a piezo member in contact with the driven object; and a cover for positioning the driven object in the receiving space and limiting a position of the pre-pressing element with respect to the housing; wherein the pre-pressing element is a metal plate provided behind the at least a piezo member, and the pre-pressing element has two end portions each provided with a resilient member, the two resilient members being respectively and resiliently fitted in two recesses on an outer lateral surface of the housing so as for the pre-pressing element to apply a predetermined pressing force to a back of the at least a piezo member to ensure constant contact between the at least a piezo member and the driven object.