Patent ID: 7806173

Claim:
An apparatus, comprising: a downhole tool configured for conveyance within a wellbore extending into a subterranean formation, wherein the downhole tool comprises: an electronics system comprising: a controller configured to execute instructions based on received data; a memory configured to store machine accessible instructions executed by the controller; and means for communicating information with a surface-located communications subassembly; wherein at least one of the controller, the memory, and the information communicating means is a heat-generating source; a heat-dissipating apparatus comprising: a chassis having a surface configured to thermally engage the heat-generating source and comprising a fluid passageway formed therethrough to allow a fluid to flow through the chassis to draw heat from the chassis and the heat-generating source; a radiator comprising a surface configured to thermally engage the chassis to enable thermal transfer from the chassis to the radiator, wherein the radiator is exposed to the wellbore so that the radiator can dissipate heat from the chassis into the wellbore, and wherein the radiator forms at least a portion of a housing of the downhole tool; a pump configured to move fluid through the passageway of the chassis, wherein operation of the pump is controlled by the controller; a first temperature sensor electrically coupled to the controller and configured to sense the temperature of the chassis, wherein the data received by the controller includes the sensed temperature of the chassis; a second temperature sensor electrically coupled to the controller and configured to sense the temperature of the wellbore, wherein the data received by the controller includes the sensed temperature of the wellbore; and a compensator comprising a spring and piston assembly configured to cooperatively regulate the pressure of the fluid in the passageway to be substantially equal to the atmospheric pressure inside of the housing; wherein the controller is configured to: acquire temperature information from the first and second temperature sensors and control the pump based on the temperature information; start the pump when the temperature of the chassis meets or exceeds a predetermined temperature threshold and stop the pump when the chassis falls below the same threshold or another threshold; start the pump when the temperature of the wellbore exceeds the temperature of the chassis and stop the pump when the temperature of the wellbore is lower than the temperature of the chassis; and increase the pump rate as the temperature of the chassis increases and decrease the pump rate as the temperature of the chassis decreases.