Four kinds of hydraulic pump construction style comparison and selection

Comparison of construction styles of four types of hydraulic pumps and selection of structural types of hydraulic metering pumps Hydraulic pressure pumps are the key components in the research and application of hydraulic transmission technology. General hydraulic pump according to the structure is divided into four categories: gear pump, vane pump, screw pump and piston pump, however, gear pump, vane pump, screw pump friction than the contact pressure is relatively large. Hydraulic quantitative pump structure type Hydraulic pump hydraulic transmission technology research and application of key components. General hydraulic pump according to the structure is divided into four categories: gear pump, vane pump, screw pump and piston pump, however, gear pump, vane pump, screw pump friction than the contact pressure is relatively large. For example, the vane pump reciprocates linearly and reciprocally with respect to the rotor guide groove during the rotation of the vane pump, and the lateral stress suffered by the vane pump is the maximum at the contact edge. In the high pressure region, the blade is pressed against the inner surface of the stator by the centrifugal force and the bottom high- Due to the contact area is small, the contact pressure is quite large. Based on the above analysis, we can see that the domestic and international water pressure pumps are used in the structure of the piston pump, one is the valve with the flow form, including the valve with the flow radial piston pump and swash plate valve axial piston pump; the other Species is a swash plate with axial flow piston pump. In addition to the use of piston pump type can reduce the friction of the contact pressure, but also because of the axial piston hydraulic motor (pump) mostly friction pair is designed using hydrostatic support method (and gear pump or vane pump There is a high line of contact Vice), greatly reducing the friction pair PV value, thereby reducing the friction pair of power loss and wear and tear, which is particularly important for the sea, fresh water hydraulic motor, because of poor lubrication of aqueous media, Elastic lubrication is difficult to form between friction pairs. Therefore, as a variable pump base pump part, will also use axial piston type. The valve-fitted axial piston pump offers high contamination resistance and, in some applications, for example as a bow-bottom drain pump, has a long life and high reliability. Valve variable displacement pump variable structure although a lot, but the structure is more complex, limited scope, making the manufacturing costs increase, technical and economic indicators are not reasonable, are not widely used. Swash plate type distribution plate with a variable axial piston pump type many, according to the type of operation can be divided into manual, motorized, electric, hydraulic and electro-hydraulic proportional control, but its basic principle is to change the inclination of the swash plate, Thus changing the pump displacement, to achieve the purpose of variables. For the swash plate with a flow distribution valve axial piston pump, in the structure of the swashplate rotating cylinder fixed and swashplate fixed cylinder rotation. For the former type, to change the inclination of the swash plate to realize the variable requires the swash plate to rotate and swivel. The variable piston needs to balance the axial thrust of all the plungers so that the structural design is difficult and the applicable surface is limited. For the latter type, the swash plate is relatively easy to achieve because it swings only.