High Inertance, Low Mass Free Piston

Summary

Vanderbilt inventors propose a free piston system that provides high inertance and tunable dynamics.

Free piston engines tend to have prohibitively fast cycle rates. Such high cycle rates currently limit the usefulness and applicability of these devices, in addition to making them difficult to control. The proposed device provides 1) slower operational speeds for the same piston mass, or 2) a lighter weight free piston machine for the same operational speed when compared to traditional free piston machines. In the context of free piston machines, the effect of slowing down the operational speed solves several problems associated with the high cycle rates typically encountered with free piston devices. Solutions to such problems include, among others, 1) the reduction in size and speed of intake valves, exhaust valves and other flow valves, 2) mitigating challenges associated with the control of such machines, 3) the capability of a balanced engine with only one piston, and 4) reduction in velocity dependent sliding piston friction.

The invention is not limited to free piston engines or machines, per se. Other applications that could benefit from this concept include, among others, absorbing recoil in guns, jackhammers and other high impulse machines.

The current stage of development of this technology is the incorporation of the device into a prototype free piston engine / air compressor.

Solicitation of Interest

Vanderbilt University intends to continue research and development of this concept utilizing funding from NSF's Engineering Research Center for Compact and Efficient Fluid Power. Concurrently, Vanderbilt solicits licensing and technical interest from industrial members of the ERC for protection and eventual commercialization of this technology.

A provisional patent application has been filed by Vanderbilt University.