US Patent 9118187 Vibrational energy harvester

Some examples include an energy harvester for use in an electronic device to convert mechanical energy associated with vibrations of the electronic device into electrical energy. For instance, an energy harvester including rows of piezoelectric cantilevers may be arranged around a proof mass and may be utilized to convert the vibrations into electrical energy. In some examples, the energy harvester may include an electromagnetic energy harvester in addition to, or in place of the piezoelectric energy harvester.