A multiple section heat pipe with swivel junctions between the sections. The individual sections are independent individual heat pipes configured to interlock with each other at rotatable joints filled with high heat conductivity liquid. The clearance between the sections is maintained small to establish capillary forces that maintain the conductive liquid in place and also to minimize the temperature differential across the rotating joint. When used in conjunction with several right angle heat pipes, the combination furnishes multiple possibilities for end to end relationship of a heat pipe system.

In a vacuum environment such as space, conductive ball and socket members are fixed to respective heat pipes for permitting orthogonal movement of one heat pipe relative to the other and the gap between the ball and socket members is maintained under a light gas pressure with the low pressure gas forming a low thermal impedance path across the gap.

The system in the present invention is an outside air ventilation cooling and room dehumidification system for use in commercial HVAC applications. The system includes a high-efficiency air filter, chilled water or evaporator precooling coil, a refrigeration compressor, an evaporator coil, a heat exchanger for removing heat and moisture from the air entering the evaporator coil and supplying heat to the air leaving the evaporator coil, a condenser coil located in the discharge airstream that reheats the air, and a fan to move the air through the coils. The heat exchanger can be a phase-change heat-pipe-type heat exchanger; a water cooling/heating coil "runaround loop"; an air-to-air plate-type heat exchanger; or a rotary heat exchanger.

An electrical apparatus, such as a distribution transformer, provided with heat pipes for cooling. The apparatus is provided with attachment wells, either extending into the cooling fluid of the apparatus or secured along the outside wall of the apparatus. Heat pipes are provided which fit into the attachment wells, with the evaporator section of the heat pipe mounted in the wells. The condenser section of the heat pipe extends away from the apparatus. Thermally conductive grease is placed in the wells to minimize the temperature drop from the wells to the evaporator section of the heat pipe.

A computer which possesses a bottom keyboard housing having a rear edge hingedly connected with the lower edge of an openable display assembly, and wherein heat-generating computer electronics contained in the housing has heat removed therefrom through the intermediary of heat pipes which are hingedly connected with at least one heat dissipator located in the display assembly. In essence, the computer incorporates an inexpensive construction of heat pipe hinges employed in the thermal interconnection of the bottom keyboard housing of the portable personal computer containing the keyboard and electronics with the display assembly, wherein the heat pipes are protected from bending stresses prior to assembling the major portions of the portable personal computer, such as the keyboard housing and the display assembly.