Its working principle is similar to that of a single-acting vane pump. The difference is that the stator surface is composed of eight parts of two long radius arcs, two short radius arcs and four transition curves, and the stator and rotor are concentric. . In the case that the rotor rotates clockwise in the figure, the volume of the sealed working chamber gradually increases at the upper left and lower right corners, which is the oil suction area, and gradually decreases at the lower left and upper right corners, which is the oil pressure area; There is a section of oil seal area between the oil pressure area and separate them. Each time the rotor of this pump rotates, each sealed working chamber completes oil suction and oil pressure twice, so it is called a double-acting vane pump. The two suction zones and two pressure zones of the pump are radially symmetrical, and the hydraulic pressure acting on the rotor is radially balanced, so it is also called a balanced vane pump.
The instantaneous flow of the double-acting vane pump is pulsating, and the pulsation rate is small when the number of vanes is a multiple of 4. For this reason, the number of blades of a double-acting vane pump is generally 12 or 16.
