Patent ID: 7692340
Filing Date: 2010-04-06
Classification: H02K,Y10T

Abstract:
1. A vibrational energy harvesting apparatus comprising: a substrate having a plurality of integral compliant regions; two ferromagnetic masses each coupled to a corresponding one or more of the integral compliant regions such that at least one of the ferromagnetic masses moves with respect to the substrate responsive to substrate acceleration, each ferromagnetic mass having an inner magnetic pole disposed such that the inner magnetic poles are separated from one another by a volume defined by the perimeters and opposing faces of the ferromagnetic masses, wherein the magnetic polarity of each inner magnetic pole is similar to the magnetic polarity of the inner magnetic pole on the opposing side of the volume; space wherein the ferromagnetic masses are disposed so as to form a steep flux gradient region in and around the volume between the inner magnetic poles; and a coil coupled to the substrate and disposed within the steep flux gradient region where the coil is exposed to a changing magnetic flux arising from motion of at least one of the ferromagnetic masses with respect to the substrate.