Electro-hydraulic control mechanism

Abstract

The invention discloses an electrohydraulic control mechanism. The electrohydraulic control mechanism comprises a first servo unit, a second servo unit, a fixed value pressure-reducing valve, a two-position three-way reversing valve and the like, wherein the fixed value pressure-reducing valve generates pressure difference to generate a pressure signal and the pressure signal is converted into a mechanical signal of the first servo unit, so that the discharge capacity of a piston variable displacement pump is controlled. The fixed value pressure-reducing valve is provided and the system pressure and the piston variable displacement pump establish a servo relationship, so that the piston variable can be adjusted according to the column system pressure. The two-position three-way reversing valve enables the piston variable displacement pump to be switched between two discharge capacity adjusting modes.

Description

technical field [0001] The invention relates to the technical field of electro-hydraulic control, in particular to an electro-hydraulic control mechanism. Background technique [0002] In the hydraulic drive system and the hydraulic control system (the two may be collectively referred to as the hydraulic system), the system pressure or working pressure is controlled and determined by multiple units or systems. For example, usually, if the displacement of the variable pump does not occur large When changing, the system pressure of the hydraulic system is mainly limited by the relief valve. When the system pressure exceeds the control pressure of the relief valve, the relief valve returns the pressure to the set system pressure by draining oil to the oil tank, and the relief valve returns to the set system pressure through the relief valve. The pressure fluctuation of the valve control system is limited. In other words, when the displacement of the variable pump changes greatl...

AI Technical Summary

Problems solved by technology

However, this method only correlates the slope of the swash plate of the variable pump with the electrical signal of the controller, and the pressure of the hydraulic system is only used as the power to simply change the lateral movement of the piston, and is not related to the displacement of the variable pump. Therefore, this method cannot adjust the displacement of the variable pump according to the system pressure, so that the adjusted displacement can only roughly meet the system requirements, and the accuracy is poor.

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