| 摘要 |
PROBLEM TO BE SOLVED: To provide a pump rotor that is capable of increasing a discharge amount without enlarging an outer diameter and a thickness in an axial direction of a rotor, and also capable of improving durability.SOLUTION: The pump rotor is provided, in a tooth profile of an inner rotor of an internal gear pump, three elliptical tooth-profile formation circles C constituting a half-tooth portion A1 of the tooth profile A. In the pump rotor: two of the tooth-profile formation circles C are a combination of a small tooth-profile formation circle and a large tooth-profile formation circle in which the small tooth-profile formation circle is inscribed and is entirely included; a portion of the small tooth-profile formation circle forms a tooth tip portion 1 in the half-tooth portion A1; a portion of the large tooth-profile formation circle in which the small tooth-profile formation circle is inscribed and is entirely included forms a meshing portion 2; and a portion of other tooth-profile formation circle that circumscribes the large tooth-profile formation circle forms a dedendum portion 3. |
