VANE PUMP

• Main Authors: KAWAHARA MAKOTO, MORI KATSUHISA, TANAKA TSUNEO, YAMAMOTO TATSUYA
• Format: Patent
• Language: English
• Published: 01.10.1991
• Subjects: BLASTING; HEATING; LIGHTING; MECHANICAL ENGINEERING; POSITIVE DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENTMACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENTPUMPS; WEAPONS

PURPOSE:To reduce the extent of pump pulsation by making a leakage flow rate variation so as to decreased by way of varying the radial width of an end-face sealing part lying between a side plate and a rotor. CONSTITUTION:When a rotor 22 rotates as far as theta and a vane is moved from an A position to a B position, at this A position, two pump chambers are opened to an inlet port 25, whereby such a stage as producing a leakage of pressure oil from a vane back pressure groove to this inlet port 25 becomes lessened. In contrast with this, at the B position, the inlet port 25 and three pump chambers are all opened whereby such a stage as producing the pressure oil leakage becomes increased. Thus, according to a variation in the stage, a leakage flow rate is little at the A position but much at the B position. At the A position, however, a vane recess groove 50 and an oil inlet part of vane back pressure come to the same position and width of a side clearance is (a), but at the B position, it shifts to some extent so that width grows larger as (b). Therefore the leakage flow rate variation being produced by a change in the stage number is offset by a relative position variation between the vane recess groove 50 and the oil inlet part 51 and thus reducible as a whole.