Patent ID: 6123533
Filing Date: 2000-09-26
Classification: F04C

Abstract:
In a gear pump for pumping liquids having dissolved air therein with meshed gears from an input to an output, the improvement comprising:a pump housing having surfaces;a drive gear within the pump housing having a plurality of symmetrical driving gear teeth, wherein each symmetrical driving gear tooth has a driving working surface and a non-working surface, each of the tooth surfaces have an arcuate profile; andan idler gear within the pump housing having a plurality of asymmetrical idler gear teeth, wherein each asymmetrical idler gear tooth has a driven working surface contacted by the driving working surface of a complementary symmetrical drive gear tooth and a non-working idler surface, the driven working surface having an arcuate profile similar to the actuate profile of the driving working surfaces and the non-working idler surface having profile less convex than that of the other surfaces for preventing damage to the surfaces by increasing backlash so that the formation of air bubbles is precluded and localized pressure spikes which cause pitting are avoided.