Closed lubrication system for bearings

Abstract

A closed lubrication system for use in bearing housings subject to a range of temperatures which isolates the air and lubricant within the bearing housing from potential contamination arising from exposure to ambient air. The invention includes a liquid-displacement expansion chamber assembly which is responsive to temperature changes in the bearing housing to accommodate volumetric expansion and contraction of supply air. A constant level lubricator is provided to maintain the quantity of lubricant at a constant sump level. A lubricant circulation assembly, including a lubricant filter, a lubricant cooler, a lubricant pump, and a sight gauge is also provided. The lubricant circulation assembly and the constant level oiler may form part of the self-contained, integral unit adapted to be selectively connected to the bearing housing. The lubricant pump may be a gear pump. The liquid-displacement expansion chamber assembly includes first chamber open to supply air and isolated from contact with ambient air, and a second chamber open to ambient air, but isolated from contact with supply air. In one embodiment, the first chamber is disposed generally below the second chamber. In a second embodiment, the first chamber is disposed generally laterally of the second chamber.