Patent ID: 8166830
Filing Date: 2012-05-01
Classification: G01F

Abstract:
1. A meter device for measuring volume flow of gas, comprising: a flow meter housing having an inlet and an outlet through which a fluid flows to rotate first and second impellers; first and second shafts in the housing that rotates in response to rotation of the first and second impellers, the first shaft being rotatably supported in the housing by at least a first roller bearing, the second shaft being rotatably supported in the housing by at least a second roller bearing, wherein each of the first and second roller bearings includes metal raceways that engage with ceramic rolling elements; and first and second timing gears having an exterior ceramic coating and that rotate in response to rotation of the first and second shafts, wherein the timing gears engaging one another along the exterior ceramic coating in an oil-less environment in which space surrounding the timing gears is free of oil.