Patent ID: 8217553

Claim:
A linear motor system comprising: an ungrounded element with a threaded passage; a threaded shaft with an axis of rotation which extends through and is at least partially engaged with at least a portion of the threaded passage; and a driving system comprising at least two planar members directly connected to respective outer planar surfaces of the element substantially along a length of the element, each of the two planar members comprises a pair of opposing members, two or more interconnected piezoelectric layers and a first set of interwoven electrodes and a second set of interwoven electrodes which are coupled to opposing surfaces of each of the piezoelectric layers and arranged to extend along the length of the axis of rotation of the shaft, wherein each set of interwoven electrodes is separately coupled to one of the pair of opposing members and the first and second sets of interwoven electrodes are coupled to a full bridge drive system, the planar members are configured to expand and contract in a direction along the axis of rotation, the driving system is configured to subject the element to vibrations causing the threaded shaft to simultaneously rotate and translate in the direction along the axis of rotation through the element and apply an axial force in the direction along the axis of rotation.