When the rotor of vane pump rotates, the tip of the vane is close to the inner surface of the stator under the action of centrifugal force and pressure oil. In this way, the working volume formed by the two blades, the rotor and the inner surface of the stator first absorbs oil from small to large, and then discharges oil from large to small. When the blades rotate for one cycle, the oil absorption and discharge are completed once.
1, Working principle of single acting vane pump
The pump is composed of rotor 1, stator 2, blade 3, oil distribution plate, end cover and other components. The inner surface of the stator is a cylindrical hole. There is eccentricity between rotor and stator. The blade can slide flexibly in the slot of the rotor. Under the action of the centrifugal force when the rotor rotates and the pressure oil flowing into the blade root, the top of the blade is close to the inner surface of the stator, so a sealed working cavity is formed between the two adjacent blades, the oil distribution plate, the stator and the rotor. When the rotor rotates in the counterclockwise direction, the right blade extends outward, and the volume of the sealing working chamber gradually increases to generate vacuum, so the oil is sucked through the oil suction port 6 and the upper window of the oil distribution plate 5. On the left. The blade is retracted, the volume of the sealing chamber is gradually reduced, and the oil in the sealing chamber is pressed out through another window of the oil distribution plate and the oil pressure port 1 and output to the system. This kind of pump absorbs and presses oil once during the rotor rotation, so it is called single acting pump. The rotor is subjected to radial hydraulic unbalanced force, so it is also called non balanced pump, and its bearing load is large. The displacement of the pump can be changed by changing the eccentricity between the stator and the rotor, so this kind of pump is variable displacement pump.
2, Working principle of double acting vane pump
Its working principle is similar to that of single acting vane pump, except that the stator surface is composed of two long radius arcs, two short radius arcs and four transition curves, and the stator and rotor are concentric. When the rotor rotates clockwise as shown in the figure, the volume of the sealing working chamber gradually increases at the upper left corner and the lower right corner, which is the oil suction area, and gradually decreases at the lower left corner and the upper right corner, which is the oil pressure area; There is an oil sealing area between the oil absorption area and the oil pressure area to separate them. The rotor of this pump rotates once, and each sealing working chamber completes oil suction and oil pressure twice, so it is called double acting vane pump. The two oil suction zones and the two oil pressure zones of the pump are radially symmetrical, and the hydraulic pressure acting on the rotor is radially balanced, so it is also called balanced vane pump.
The instantaneous flow of double acting vane pump is pulsating, and the pulsation rate is small when the number of vanes is a multiple of 4. Therefore, the number of blades of double acting vane pump is generally 12 or 16.
