Patent ID: 9705430
Date: 2017-07-11
CPC Classifications: H01L,H02N,Y10T

Claim:
1. A method of forming an energy harvesting device for harvesting vibrational energy from an external vibration structure, the method comprising: supporting, using a support element, an outer peripheral edge of a first disc spring, wherein the support element is configured to allow oscillations of the first disc spring relative to the support element, the oscillations responsive to vibrational energy received from the external vibration structure; applying a first preload force to the first disc spring directed along an axial center of the first disc spring; fixedly securing, during application of the first preload force, a first piezoelectric material with a surface of the first disc spring; and applying a second preload force to the first disc spring to thereby provide a predetermined reduction of a stiffness of the first disc spring, wherein the reduction of the stiffness corresponds to an increased sensitivity to low-frequency components of the vibrational energy received from the external vibration structure.