Thermally Conductive Vibration Isolation System for Cryocoolers

With the increasing demand for high temperature cryoelectronics and sensitive spaceborne multi-spectral imaging and detector systems, reliable mechanical cryocoolers have become an enabling technology. These cryocoolerscollers share two undesirable characteristics, vibration and heat generation. Vibration reduction has focused on multi-harmonic axial vibration cancellation using active counterbalance mechanisms; heat removal has relied upon heat sinking using heavy copper braid. Technology Applications has defined an integrated, thermally-conductive, vibration isolation system that fits between the cryocooler and instrument housing assembly. This system incorporates a six-axis vibration isolation system that employs compact, efficient electromagnetic actuators, force sensors, and passive dampers. A carbon-aluminum composite flange that attaches to the cryocooler interface flange preferentially conducts heat from the cryocooler to a flexible graphite fiber thermal strap that connects to the heat rejection interface. In Phase I, representative cryocooler thermal and vibration characteristics will be defined, preliminary designs and detailed analysis completed, and vibration isolation and heat transfer demonstration testing conducted to verify concept feasibility. This will provide a solid basis for the Phase II research and development effort that will ultimately provide simple, reliable and inexpensive, integrated cryocooler vibration isolation and heat removal system for a wide range of commercial and aerospace applications. Benefits: Effective and inexpensive vibration suppression and heat rejection and essential to many cryocooler applications ranging from multi-spectral imaging to high temperature superconductors (HTS). Potential applications include: portable fourier transform infrared (IR) spectroscopes for environmental pollution measurement; HTS filters for cellular communications/radars; tactical IR imaging; and HTS phase-array antennas.|