No. 6007, zhenpu road, xiepu town, zhenhai district, Ningbo
What is the working principle of the micro hydraulic power unit
System with open and closed systems. Small tonnage crane usually adopt the open system with directional control valve control. Implementing actuators are. Reverse direction and braking requirements.. Large tonnage crane mostly adopts closed system, closed system adopts the bidirectional variable pump. Through variables change in the main oil of pump of hydraulic oil flow and direction. To achieve variable speed and the reversing of the actuator. This kind of control mode. You can fully embodies the advantages of hydraulic transmission.Large tonnage crane hydraulic working device. Usually the swashplate axial piston closed system composed of variable pump and quantitative motor. Swashplate variable plunger pump flow rate is proportional to the driving speed and displacement. And can be stepless variable. Closed loop variable pump connected to the motor oil outlet and inlet. The oil outlet and inlet of the pump motor. To form a closed hydraulic circuit. Without reversing valve. By adjusting the Angle of inclined plate of variable pump to change the direction of flow and pressure of pump oil. To change the motor rotation speed and direction of rotation. The variable pump flow change with swinging Angle of inclined plate can be increased from zero to the maximum. When the swash plate is placed through the median. CanChange the direction of liquid flow smoothly. Therefore, the fretting is good and the work is stable.Closed has oil leakage in the hydraulic drive system work (continuous drainage in the high pressure oil is inherent) of component design, hydraulic power unit spare parts in order to replenish these leaks and consumption. Maintain a closed system to work normally. You must give timely supplement oil closed system. Closed system flux on the main pump shaft with a smaller pump. Due to the main pump filling pump displacement and stress are very small. So the additional power loss usually only for 1% to 2% of the total power can suddenly cough up. In the closed system of the hydraulic device is equipped with oil overflow valve and check valve oil. Tonic fill the oil pressure relief valve limits the highest filling oil. OilCheck valve baseOn both sides of the hydraulic oil pipeline of high and low pressure. Choose oil compensating direction. To fill oil. On the low voltage side of the oil to offset due to the pump. Motor leakage flow volume loss, both sides of the main pump is equipped with two high pressure relief valve. There was a peak pressure of the inclined plate fast swing and maximum pressure by the high pressure relief valve protection. Prevent the pump and motor overload, the hydraulic device will also include a pressure cut-off valve. Pressure cut-off valve is equivalent to a kind of pressure regulation. When set pressure is reached. The correction of oil pump capacity to zero state. In addition, the filling pump outlet filter. Also has working medium for hydraulic system to filter. Improve the cleanliness of hydraulic oil.Closed system has the following advantages:
1, industrial hydraulic power unit is currently closed system structure of variable pump are integrated. Oil pump and oil tonic. Overflow. Integration on the hydraulic pump control valve group. Make the connection easier. Not only reduces the installation space. And to reduce the leakage and piping vibration caused by pipeline connection. To improve the reliability of the system. To simplify the operation process.2, lifting equipment accessories manufacturers of fill oil system can not only in the main pump displacement change guarantee the displacement response of the transmission. To improve action frequency of the system. Can also increase the main pump inlet pressure. Prevent large flow cavitation. Can effectively increase the pump rotation speed and prevent the pump suction empty. Improve the working life, filters are installed in the oil filling system. Increase the reliability of the transmission device and service life, in addition. Oil pump can also be convenient for some low voltage power auxiliary mechanism.
3. As only a small amount of oil is absorbed from the tank, the loss of the tank is reduced.
Address：No. 6007, zhenpu road, xiepu town, zhenhai district, Ningbo