System, method and apparatus for reducing frictional forces and for compensating shape memory alloy-actuated valves and valve systems at high temperatures

摘要

A valve system including a number of shape memory alloy (“SMA”)-actuated valves for controlling the flow of fluids is disclosed as is a variety of types of SMA-actuated valves and methods of operation. In one embodiment, a valve system includes a housing having a substantially closed cavity as well as a second port for communicating a fluid. Further, the valve system includes a first SMA actuator configured to control the position of the first seal to vary fluid flow through the firs port, and a first temperature compensator for adjusting the position of the seal by an amount proportional to temperature. A second SMA-actuated valve, driven by either a unidirectional or a bidirectional SMA actuator, controls the position of the second seal to vary fluid flow through the second port, and a second temperature compensator for adjusting the position of the second seal by another amount proportional to temperature.