US Patent # 6,844,054 THERMAL MATERIAL,DEVICES AND METHODS THEREFORE
The present invention provides thermal devices, materials and methods for use in transferring heat from heat sources. One embodiment comprises a thermal transfer body that has first and second end portions and includes a thermally anisotropic material that conducts more thermal energy in a longitudinal direction than in a direction transverse thereto, wherein at least one of the first and second end portions includes a projection having a surface area oriented obliquely to the longitudinal direction. Multiple projections may be provided of various geometries, such as pyramids, cones, triangular prismoids and domes. The thermally anisotropic material may include an ensemble of longitudinally thermally conductive fibers, such as carbon fibers derived from precursors such as petroleum or coal pitch, which may be embedded in a support matrix of various materials.
The patent covers angular pin/fin geometries when produced from anisotropy materials that conduct more thermal heat energy in one direction than other directions. With these advanced nano and micro conductive fibers and fiber array devices, as with conventional conductive metals, you still need a higher surface area on the heat transfer side of a thermal device and on the individual fiber ends themselves. A good way to achieve this is with pin/fins. Independent testing has proven that with conventional straight pin/fins, a carbon heatsink has less heat transfer (higher resistance) than a aluminum heatsink of the same configuration whereas with the angular pin/fins (same transfer surface area) the carbon has superior transfer-lower resistance.
These nano and micro fibers can provide superior thermal management than metals, which sink the heat into the metal material and then dissipate at a different rate or flux. A equivalent ThermoComposite heat sink(transfer) device doesn't sink or flux heat but transfers heat between environments with lower thermal resistance, providing for cooler heat source device operation than a metal heat sink.
This technology offers superior thermal capabilities than existing metal heat sink/heat pipe systems and can enhance or even eliminate the use of "in-situ" thermal management assistance devices such as fans, liquid cooling/radiators and TEC approaches.
ThermoComposite technology further allows the manipulation of the directional transport of thermal energy from heat generating elements and/or systems to remote dissipation or collection areas with minimal thermal contamination of operating environments along the path(s) of transfer. The technology also enables manipulation of thermal energy by connectors, switches and the spreading or concentration of thermal heat energy.