VANE PUMP

• Main Authors: TSUCHIYA KEIJI, SASAYA HIDEAKI, NARA AKIO
• Format: Patent
• Language: English
• Published: 14.12.1982
• Subjects: BLASTING; ENGINE PLANTS IN GENERAL; HEATING; LIGHTING; MACHINES OR ENGINES IN GENERAL; MECHANICAL ENGINEERING; POSITIVE DISPLACEMENT MACHINES FOR LIQUIDS; 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

PURPOSE:To raise the volumetric efficiency of a vane pump, by reducing leakage of oil by increasing the sealing area at the position where a cylindrical rotor is held in sliding contact with the inner surface of a cam-shaped cylinder, by constituting the inner surface of the cylinder with cycloidal curves connected to each other, and shaping the inner surface of the cylinder at the regions near the contact lines between the rotor and the inner surface of the cylinder to have arcuate sealing surfaces. CONSTITUTION:The inner surface 6a of a cam-shaped cylinder is constituted with six cycloidal curves connected to each other at the intervals of pi/3. By employing such an arrangement, it is enabled to lower the differential value dR/ dtheta near three sliding contact lines (theta=0.2pi/3.4pi/3) formed between the inner surface 6a of the cylinder and the outer surface of a cylindrical rotor 1 (where R is the moving diameter and is equal to a+d/2+d/2Xsin(3theta-pi/2)), and substantially area seal can be obtained instead of line seal at the contact regions, so that the volumetric efficiency can be raised since leakage of oil can be reduced. Further, since dR/dtheta and d R/d theta are both zero at each connecting point of the cycloidal curves, vanes 3 can be moved smoothly along the inner surface 6a of the cylinder.