Gear Dynamics and Gear Noise Short Course
(June 2 - 5, 2025)

2018 R&D 100 Award Finalist

Innovative Product: Quasi zero stiffness disk spring isolator (QZS-DSI) to improve comfort in automobiles

Developers: NVH & Gear Education, LLC and Toyota Motor Engineering & Manufacturing North America, Inc.
Year: 2018

Link to R&D 100:

Innovative vibration isolation device has been designed based on coned disk elements in order to exploit their nonlinear load-deflection characteristics. It consists of a series stack of conned disk springs with specially designed fixtures that allow its springs to invert. Such nonlinear displacements facilitate their quasi-zero stiffness regime(s) to be leveraged to achieve highly desirable isolation at very low frequencies which are not otherwise possible. The frequency range is specific to the targeted application. The nonlinear disk spring isolator could be scaled to work in several different situations, but it must be tailored to fit the needs or specifications. There is an extreme loading limit of the device. Due to the nature of the mating conditions between the washers and coned disks, the springs can buckle and be pushed through the supporting fixture. Therefore, knowledge of loading condition(s) that the isolator will be subjected to is critical. This innovation achieves a low cost, robust and adaptable design to approach nearly zero stiffness regime(s) using a cascaded arrangement of coned disks and fixtures.

Scientific Articles
  1. N.P. Mastricola, R. Singh, Nonlinear Load-Deflection and Stiffness Characteristics of Coned Springs in Four Primary Configurations, Mechanism and Machine Theory, 116, 513-528, 2017 (doi: 10.1016/j.mechmachtheory.2017.06.006).
  2. N.P. Mastricola, J.T. Dreyer and R. Singh, Analytical and Experimental Characterization of Nonlinear Coned Disk Springs with Focus on Edge Friction Contribution to Force-Deflection Hysteresis, Mechanical Systems and Signal Processing, 91, 215-232, 2017 (doi: 10.1016/j.ymssp.2017.01.009).

• Three patent applications have been filed.

Contact for more details: Dr. Raj Singh [email:]