Anti-galling pump rotor for an internal gear pump

• Main Author: HOSONO KATSUAKI
• Format: Patent
• Language: English
• Published: 15.12.2009
• Subjects: BLASTING; ENGINE PLANTS IN GENERAL; HEATING; LIGHTING; MACHINES OR ENGINES FOR LIQUIDS; MACHINES OR ENGINES IN GENERAL; MECHANICAL ENGINEERING; OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR; POSITIVE DISPLACEMENT MACHINES FOR LIQUIDS; POSITIVE-DISPLACEMENT ENGINES DRIVEN BY LIQUIDS; PRODUCING MECHANICAL POWER; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS; ROTARY-PISTON OR OSCILLATING-PISTON MACHINES OR ENGINES; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENTMACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENTPUMPS; STEAM ENGINES; WEAPONS; WIND, SPRING WEIGHT AND MISCELLANEOUS MOTORS

In pump rotors and used in an internal gear pump, which includes an inner pump rotor having outer gear teeth; an outer pump rotor having inner gear teeth that mesh with the outer gear teeth ; and a casing having a pumping-in port through which a fluid is pumped in, and a pumping-out port through which the fluid is pumped out, and pumps in and pumps out the fluid by changing the cell volume formed between gear tooth surfaces of the rotors and so as to carry the fluid when the rotors and mesh with each other and rotate, the rotors are formed from a sintered material of Fe-Cu-C and have a density of not less than 6.6 g/cm3 and not more than 7.1 g/cm3, and the outer circumferential surface of the outer pump rotor and the end surfaces perpendicular to rotation axes of the rotors and are non-grinded surface and have a ten point height of irregularities Rz of not less than 4 mum and not more than 10 mum.