The "heart" of the hydraulic system

As the heart of the hydraulic system, the hydraulic pump provides power for the hydraulic system, and its performance plays an important role in the normal operation of the system. This article mainly introduces the structure and basic principle of gear pump, plunger pump and vane pump.

1. The structure of the gear pump mainly includes: driving and driven gears, drive shaft, pump body, side plate, etc. The meshing line of the two gears divides the pump body into two chambers: the oil suction chamber and the oil pressure chamber.

2. The piston pump generally changes the volume of the closed cavity through the reciprocating movement of the piston to absorb and discharge oil. It has the characteristics of small leakage and high volumetric efficiency, and is widely used in high-pressure systems. Including axial piston pump and radial piston pump, axial piston pump has two kinds of swash plate type and inclined shaft type. The piston pump has complex structure, high technical content, many variable modes, and high requirements for materials, processes and heat treatment. At this stage, the technical level of piston pumps in my country is still far behind foreign countries. Taking the common swash plate axial piston pump as an example, the principle of the piston pump is described. The main structure of the swash plate axial piston pump is: pump body, piston, swash plate, cylinder block, flow plate, etc.

3. There are two types of vane pumps: single acting and double acting. Double-acting vane pumps are quantitative pumps, and single-acting vane pumps are capable of variable displacement. Vane pumps are widely used in machine tools, engineering machinery, metallurgical equipment and other fields. It is characterized by small flow pulsation, low noise, and stable operation, but it has higher requirements for oil cleanliness. The main structure of the pump is: stator, rotor, vane, distribution plate, etc.