Existing domestic and foreign loader hydraulic system technology:
With the gradual shift towards large tonnage and reasonable power distribution, an important manifestation of overall performance is the direction of the loader. At the same time, saving has become more and more important. Internationally, it is considered that the existing hydraulic system hydraulic power steering system hydraulic system, a shunt work, the method of combining shunts has the following two areas: a valve control circuit, the system has two A main hydraulic power source. With the addition of two priority valve systems, the steering system will not be separated from the safety valve. If it does not open, the pressure gradually rises P1 and promotes the priority valve to leave.
A diverter valve hydraulic system together
Supervise the working system pressure pump oil, double pump confluence. When the machine rises in the country, the working pressure increases sharply, exceeding the rated pressure, the overflow in the high-pressure hydraulic system causes a great waste of energy, and the sharp increase in the oil hydraulic system damages the entire fatal system. For another pump control, the hydraulic system has three main power sources.
When the loader lifts off the boom state, the on-off valve is left and the dual pumps merge, increasing the flow rate in the work unit, which increases the bucket high-speed elevator. The correct shut-off valve, fuel flow to reduce the work of the equipment, by switching the hydraulic oil flow to the pump back to the tank, reducing part of the hydraulic load, this part of the power is allocated to the driving wheels to improve traction. Although this system can save energy, it is difficult to achieve higher efficiency except for lifting the prosperity of the country, and the excavation is still in a high pressure overflow state, causing fatal damage to the machine. As a result, the system is more complex, at the expense of greater economic efficiency.
Two-pump controlled hydraulic system combined with shunt
In order to save energy, reduce costs, and reduce the damage to the hydraulic system, the temperature rises. Therefore, high-efficiency and reliable machine operating conditions are used to avoid work at pressure levels or above during cornering. The waste of energy, and the dramatic increase in fatal damage to the entire system in the hydraulic system, especially the invention of the hydraulic system, a low cost, high reliability system, can greatly improve the machine's high power utilization rate, automatic voltage overflow, and automatic shutdown. The temperature, protection system confluence, and greater breakthrough power. Improved loader of large tonnage, high performance and high flow hydraulic system, greatly improving power efficiency. Greatly improve the overall performance, intelligent control machine becomes possible.
Description of controllable double pump combined and split hydraulic system:
The hydraulic system is combined with the diverter valve system. There are two main power sources for the working pump and the steering pump. The steering and hydraulic system control valves plus a common isolation control. The working dual pump combined diverter valve electromagnetic control valve is shown in Figure 4. Interface for machine three with magnet alarm system.
This valve is normally open to P-phenolic, PF and T-port normally closed valves. When the phenolic pressure is the same as that of the main spool, if the steering system does not work, please go to the first control valve pressure oil pump combination two and enter The hydraulic system of the P-port provident fund working hydraulic system, the two pumps merge, improving the efficiency of the machine. When the machine rises or is overloaded by the correct throttle valve, the working hydraulic system pressure exceeds 18Mpa. Acting, if the force F is greater than the spring setting, Control the dual-pump diverter valve left, P and T port oil, low pressure overflow steering system, steering system to avoid overflow under high pressure to reduce power loss and hydraulic oil temperature.
If a long-term high-pressure overflow state machine, the oil temperature rises to the system setting, the oil temperature sensor signals to the controller through the alarm system at three levels, the controller sends an electronic signal to control the dual pump joint diverter valve solenoid when energized, it has the right Promote the communication of valve core 4, P port and T port, the pressure of steering system overflows. The confluence of the two pumps does not prevent the oil temperature from increasing, resulting in system damage.
Advantages and positive effects:
This system has the following advantages and positive effects:
a) For the large tonnage, the high pressure and large flow valve loader hydraulic system combines the performance of the system shunt system, which greatly reduces the heat dissipation capacity of the machine and can greatly improve power efficiency. Greatly improved overall performance.
2) In addition to the low cost of combining a three-pump parallel system, good economic efficiency.
C) The entire hydraulic system provides reliable pressure and temperature protection, which improves the life and reliability of the system.
4) Compact structure and easy manufacturing.
e) The implementation of intelligent control on the possible intelligent control machine and easy machine.