According to the working principle of the vane pump, whether it is an unbalanced vane pump or a balanced vane pump, the following conditions must be met in order to ensure its normal operation:

1. While the blade rotates with the rotor, it should be able to move flexibly in the groove of the hand blade without jamming. The purpose is to make the length of the blade protruding out of the outer circle of the rotor can be changed with the change of the curve in the stator, and the change of the sealing volume of the oil suction chamber and the pressure oil chamber is formed to achieve oil absorption and oil discharge.

2. The top of the blade is in close contact with the inner surface of the stator, sliding along the inner surface of the stator, and no voiding occurs to form a sealed working volume.

3. Each relative sliding surface, including the blade and the rotor blade groove, the rotor end face, the stator face and the blade end face and the two side plates (distribution plate) must have a reliable seal to limit the oil pressure chamber and the oil suction chamber The leak between. To this end, the matching clearance of these surfaces must be strictly controlled.

4. When the sealing volume between two adjacent blades gradually expands to the maximum in the oil absorption zone, it should first be cut off from the oil suction chamber and then quickly transferred to the pressure oil chamber to prevent direct communication between the pressure oil chamber and the oil suction chamber. For this purpose, the circumferential spacing between the suction and discharge windows of the distribution plate is required, that is, the two oil sealing angles should be equal to or slightly larger than the angle between the adjacent two blades. At the same time, in order to avoid the phenomenon of oil trapping, the volume between the two oil blades should be kept constant within the range of angles of the two oil sealing angles.

5. When the pump starts, it must have enough rotation speed to generate the necessary centrifugal force to pry the blade out so that the blade can also adhere to the inner surface of the stator under the condition that there is no oil pressure at the root to form a sealed volume. The pump enters the suction and pressure oil working state

6. The oil suction chamber should be filled with oil, and no suction should occur. Otherwise, the air will be mixed and the pressure chamber will not establish pressure properly. In order to ensure continuous oil absorption, there are certain limits on the maximum speed and oil viscosity. When the rotational speed exceeds 1800r/min, the oil may be insufficiently supplied due to the excessive oil absorption rate, unless structural measures are taken to enlarge the oil absorption passage; the oil is too thick and the flow resistance is large, which may easily cause insufficient oil absorption.