Loader hydraulic system and loader

Abstract

The invention relates to a loader hydraulic system and a loader, and belongs to the technical field of engineering machinery. The loader hydraulic system comprises a hydraulic oil tank, a duplex gearpump, a third hydraulic pump, a working hydraulic cylinder and a steering hydraulic cylinder, wherein the duplex gear pump comprises a first hydraulic pump and a second hydraulic pump; the first hydraulic pump, the second hydraulic pump and the third hydraulic pump all communicate with the hydraulic oil tank; the steering hydraulic cylinder is connected with a steering gear; the third hydraulic pump is connected with the working hydraulic cylinder through a multi-way valve; a priority valve is connected with the multi-way valve; and a priority unloading valve is connected between the duplex gear pump and the priority valve. The loader hydraulic system and the loader overcome the defects in the prior art, prevent heavy low-rotating-speed and idling of an engine and excessive energy loss, guarantee the power of the engine and the operation efficiency of the whole machine, reduce the complexity of the hydraulic system, and are more convenient to manufacture, maintain and repair.

Description

technical field [0001] The invention relates to a loader hydraulic system and the loader, belonging to the technical field of construction machinery. Background technique [0002] The loader hydraulic system is generally composed of a working hydraulic system and a steering hydraulic system. The working hydraulic system is generally composed of a working pump, a multi-way valve, a working hydraulic cylinder and its pipelines; the steering hydraulic system is generally composed of a steering pump, a priority valve, a steering and its pipeline composition; [0003] In the prior art, there are generally 5 schemes for the hydraulic system of the loader: [0004] The first solution is a two-pump non-converging system, that is, the working pump is separately supplied to the working hydraulic cylinder in the working device, and the steering pump is separately supplied to the steering cylinder; [0005] The second solution is a double-pump confluence system. The steering pump supp...

AI Technical Summary

Problems solved by technology

[0009] Among the above five schemes, the hydraulic systems of Scheme 4 and Scheme 5 are relatively complex, and the cost of manufacturing, maintenance, maintenance, etc. is relatively high;

[0010] Scheme 1 has a simple hydraulic system, but the displacement of the pump will be large, the hydraulic system will occupy a large amount of power, and the power loss will be large;

[0011] Solution 2 is to solve the problem of heavy steering when the engine is idling. The displacement of the steering pump should not be too small, but when the engine is running at high speed, the energy loss will be relatively large;

[0012] Solution 3 solves the problem of heavy idling at low engine speed and energy loss, but existing users are getting heavier and heavier, and have higher and higher requirements for the efficiency of the whole machine. However, due to the limitation of engine power, it is difficult to make further improvements

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