Hydraulic working system and control method of loader without overflow loss

Abstract

The invention discloses a hydraulic working system of a non-overflow-loss loader. On the original structure basis of an engine, a transmission shaft, a filter, an oil tank, a metering pump, a multi-way valve, a rotating bucket oil cylinder, a boom cylinder, a safety valve and a double-action safety valve, a first two-position three-way reversing valve and a high-pressure energy accumulator are additionally arranged between the multi-way valve and the metering pump, a low-pressure energy accumulator and a second two-position three-way reversing valve are additionally arranged on an oil return oil way, and the pressure values of the energy accumulator are measured through a pressure sensor. The first two-position three-way reversing valve and the second two-position three-way reversing valve are controlled so that the output flow of the metering pump can be matched with the required flow of loads (the outer loads and the energy accumulators), energy consumption caused by the overflow loss is completely avoided, energy consumption caused by the throttling loss is reduced, and the whole machine efficiency is improved. The descending potential energy of a boom is recovered through the low-pressure energy accumulator for driving a steering mechanism, and the energy use rate is further increased.

Description

technical field [0001] The invention relates to the technical field of engineering machinery, in particular to an energy-saving hydraulic working system and a control method for a loader without overflow loss Background technique [0002] The hydraulic working system is an important part of the loader, which is widely used in mining, road administration, construction and other fields. At present, small and medium-sized loaders generally use quantitative pumps. During the working process, there will be a phenomenon that the flow rate of the pump does not match the load demand, resulting in overflow loss, resulting in a decrease in fuel economy and an increase in the temperature of the hydraulic oil. This is not conducive to environmental protection and will reduce the service life of the hydraulic oil, thereby affecting the reliability and efficiency of the entire hydraulic system and components. Large loaders generally use variable displacement pumps, which are expensive an...

AI Technical Summary

Problems solved by technology

At present, small and medium-sized loaders generally use quantitative pumps. During the working process, there will be a phenomenon that the flow rate of the pump does not match the load demand, resulting in overflow loss, resulting in a decrease in fuel economy and an increase in the temperature of the hydraulic oil.

This is not conducive to environmental protection and will reduce the service life of hydraulic oil and affect the reliability and efficiency of the entire hydraulic system and components

Large loaders generally use variable displacement pumps, which are expensive and sensitive to pollution

[0003] At present, the energy-saving technologies mainly used in the product include double-pump confluence technology and double-pump confluence equivalent unloading technology, but neither of them has completely solved the overflow problem, so the energy-saving effect is very limited

Although variable displacement pump technology can reduce power loss, it is currently difficult to popularize due to its high cost

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