Abstract: An electromagnetic generator comprising a multilayer assembly of a first layer carrying at least one magnet, a second layer carrying at least one coil, and a third layer carrying at least one magnet, the at least one magnet of the first and third layers being configured to define therebetween a region of magnetic flux in which the at least one coil is disposed, at least one of the layers being shaped to define a respective displaceable portion thereof which is displaceable by vibration of the electromagnetic generator thereby to cause relative movement between the coil and the magnets and generate an electrical current in the coil.

Abstract: A triple beam resonator (10) is provided with three beams or tines (12, 14, 16) aligned in parallel alongside each other and joined at a decoupling zone (18) at each end, which is in turn connected to the surrounding material. The central beam (14) is twice the width of the two outer beams (12, 16). The resonating element has a length of 15.5 mm, a thickness of 0.25 mm and beam widths of 2 mm and 1 mm. The distance between the beams is 0.5 mm. Finite element analysis predicts the modal behavior with stress distribution and eigenfrequencies of the resonator (10). Thick-film PZT elements (20, 22) were printed on separate regions at each end of the central beam (14), where maximum stresses exist as the resonator (10) operates in its favored mode of vibration. The PZT element (20) at one end drives the vibrations, while the PZT element (22) at the other end detects them.