Internally controlled gear pump used in pressurized control system, has axial grooves that extend axially over entire length of inner rotor, where ratio of radius of outer tooth root surface and radius of groove is of specific value

摘要

The gear pump (10) has inner rotor (14) that is rotatably mounted in gear chamber, and an outer tooth (20) that is accommodated in gear chamber race (18). An internal tooth (25) is in a meshing engagement with outer tooth, so that fluid can be conveyed from inlet ports by relative movement between inner rotor and race to outlet. The ratio of radius of root surface of outer tooth in area between adjacent teeth (22) and the radius of axial grooves (46) extending axially over entire length of inner rotor is 1.1 to 3.0.