Heat Pipe Technology Spinoffs
A Bellows Heat Pipe
(G.P. Peterson and S. Oktay - U.S. Patent No. 4,951,740 issued August 28, 1990)
A novel bellows heat pipe to conduct heat away from electronic components to a heat sink has been developed. The heat pipe operates as a thermal switch to cool electronic components and insures that the temperatures in the components do not fall below or exceed predetermined levels. This design can be used as a stand-alone mechanism for individual microelectronic components in multicomponent modules or on a larger scale as a flexible thermal contact for electronic equipment or systems.
Heat Transfer Cylinder
(L.S. Fletcher and G.P. Peterson - U.S. Patent No. 5,119,886 issued June 9, 1992)
A heat transfer cylinder using heat pipes to provide a constant temperature surface has been developed for use in the paper industry for drying, rolling, or otherwise processing a work piece. The heat transfer cylinder includes a plurality of heat pipes around the periphery of the cylinder wall, or the heat transfer cylinder may be treated as a large heat pipe with the cylindrical surface serving as the condenser. The use of such a heat transfer cylinder could lead to a more energy efficient drying process. In addition, such a cylinder could be used for dissipation of heat in rolling mills where the work piece is a hot ingot.
Vapor Deposited Micro Heat Pipe
(M.H. Weichold, G.P. Peterson, and A.K. Mallik - U.S. Patent No. 5,179,043 January 12, 1993)
A technique has been developed by which very small micro heat pipes, approximately 35µm in diameter can be fabricated as an integral part of semiconductor devices. These heat pipes function as highly efficient heat spreaders collecting the heat from localized hot spots and dissipating over the entire chip surface. Incorporation of these heat pipes as an integral part of silicon wafers has been shown to significantly reduce the maximum wafer temperature and reduce the temperature gradients occurring across these devices.
Micro Heat Pipe Catheter for Local Tumor Hyperthermia
(L.S. Fletcher and G.P. Peterson - U.S. Patent No. 5,190,539 March 2, 1993)
A micro heat pipe catheter the size of a hypodermic needle (~1 mm) may be charged with an appropriate working fluid to assure constant temperature operation within a therapeutic temperature range of 42.5°C (108.5°F) to 43°C (109.4°F) for use in hyperthermia cancer treatments. The micro heat pipe will provide a controllable heat rate at constant temperature and may be matched to the thermal conductivity of the tissue and the degree to which the cancerous tumor is perfused. The micro heat pipe catheter may be used to treat cancerous tumors in body regions which heretofore could not the treated by other means. The micro heat pipe catheter may also be used for cryosurgery applications with appropriate support facilities.
Temperature Control Mechanisms for Micro Heat Pipe Catheters
(G.P. Peterson and L.S. Fletcher - U. S. Patent No. 5,417,686, May 23, 1995)
Temperature control mechanisms for use in conjunction with heat pipe catheters have been designed and developed. These control mechanisms include passive techniques such as gas loading, excess liquid charging, vapor flow modulation, and liquid flow modulation; and more active systems that utilize thin film technology such as a vapor deposited thermocouple for use with active feedback control mechanisms. These passive and/or active temperature control mechanisms will allow temperature control to within ± 0.02°C. These techniques when coupled with a micro heat pipe catheter constructed from any one of a number of materials and working fluids could successfully be used for tissue cauterization in surgical applications or the destruction of cancerous tissue.
Micro Heat Pipe Panels and Method for Producing Same
(C.J. Camarda, G.P. Peterson, and D.R. Rummler - U.S. Patent No.5,527,588, June 18, 1996)
A technique has been proposed for fabricating a series of micro heat pipes into thin, flat or curved panels made of refractory materials. These panels would exhibit an extremely high effective thermal conductivity and could be used as a highly conductive outer skin for the leading edge of engine cowling or wing surfaces on hypersonic vehicles. The resulting high effective conductivity of the exterior skin would serve to spread and dissipate the heat generated by local stagnation heating on these surfaces. (Currently ITAR restricted).
Treatment Method Using a Micro Heat Pipe Catheter
(G.P. Peterson and L. S. Fletcher - U.S. Patent No. 5,591,162, January 7, 1997)
Micro heat pipes are capable of providing an acceptable method for isolating and eliminating cancerous tissue in a number of applications where traditional surgical removal is not possible. A number of new methods for applying this technology have been developed and are currently under further investigation. These techniques may provide significantly improved treatment techniques for both operable and inoperable cancerous tissue.
Coupled Flux Transformer Heat Pipes
(G. P. Peterson and S. Oktay - U.S. Patent No. 5,647,429, January 15, 1997)
A new technique has been developed to overcome the capillary limitation normally encountered in extremely long heat pipes. This technique, when combined with the advantages of flexible heat pipes with variable cross-sections can provide a highly efficient method for removing and dissipating the heat generated in the high power electronic packages developed for the computer industry.
Micro Heat Pipes with Variable Channels and Variable Contact Angles
(G. P. Peterson and H. B. Ma - Patent Pending)
A novel heat pipe design has been developed which allows the contact angle and cross-sectional area to both be varied along the axial length of a heat pipe. This concept, which has particular application in the electronics industry has the potential to significantly increase the heat transport capacity of conventional and micro scale heat pipes.