Pressure compensator and lubricating reservoir with improved response to substantial pressure changes and adverse environment

摘要

Improved lubricant pressure compensation is achieved in apparatus operative between substantially different changing pressures, for example earth drilling tools and deep submergence ocean machinery, by a flexible hermetically sealed gas-containing chamber which is operative to apply ambient pressures through the interiorly contained gas to a flexible wall membrane which at least partially defines a lubricant containing reservoir. The pressure exerting chamber and the lubricant containing reservoir may both be defined by flexible bladder-like structures with the lubricant containing reservoir contained within the interior of the pressure exerting chamber. In earth drilling apparatus, the reservoir and chamber structures are preferably operatively positioned on a drill collar in adjacency to a rotary drill bit, and lubricant is communicated through passageways from the reservoir to the bearing and seal assemblies operative between the drill bit body and the rotationally mounted cutter wheels.