Variable displacement oil pump cavitation control method and device

Abstract

The invention relates to a variable displacement oil pump cavitation control method and device, and relates to the technical field of oil pumps. The method comprises the following steps: determining acavitation engine rotating speed range and a cavitation oil pump displacement range; obtaining a cavitation corresponding relation table among the rotating speeds of all engines, corresponding oil pump displacement limiting values and corresponding oil pump electromagnetic valve duty ratio threshold values in the cavitation engine rotating speed range; acquiring the corresponding current oil pumpdisplacement limiting value and the current oil pump electromagnetic valve duty ratio threshold value; when the current oil pressure value does not reach the target oil pressure value, increasing theoil pump displacement by reducing the current oil pump electromagnetic valve duty ratio; and when the current oil pump displacement reaches the oil pump displacement limiting value and the oil pressure value of a main oil way is reduced to the oil pressure alarm threshold value, sending out oil warning information. According to the variable displacement oil pump cavitation control method and device, the oil pump electromagnetic valve duty ratio is adjusted in real time by controlling a variable displacement oil pump, the oil pump is limited to reach the displacement prone to cavitation, and the oil pump is prevented from running in a cavitation area.

Description

technical field [0001] The invention relates to the technical field of oil pumps, in particular to a cavitation control and device for variable displacement oil pumps. Background technique [0002] At this stage, in order to comply with the requirements of energy saving and emission reduction of engines, the following three changes have occurred in engines: 1. More and more engines use vane-type variable displacement oil pumps; The displacement is getting bigger and bigger; 3. Considering the good carrying performance of the engine, the volume requirements for the oil pump and other parts tend to be stricter. [0003] The above three restrictions will lead to a smaller volume of the oil pump and a larger displacement. At this time, the oil pump is prone to cavitation at the normal speed of the engine, resulting in damage to the oil pump and engine bearing bush. [0004] The cavitation of the oil pump is generally caused by the following reasons: 1. The pump suction flow rat...

AI Technical Summary

Problems solved by technology

Once the engine works at the oil pump cavitation speed, the oil pump will be damaged and the engine bearing bush will be damaged in just a few hours.

[0005] In order to achieve the above purpose, in the existing improvement technical scheme, the oil pump suction port must be designed very large to ensure that the resistance of the oil pump suction port is small enough, and the internal structure of the oil pump needs to be optimized to avoid cavitation caused by excessive local flow velocity; but It will make the volume of the oil pump larger, and it often cannot achieve the purpose in the current compact engine. It cannot guarantee that the oil pump will not produce cavitation at the maximum engine speed and the maximum displacement of the oil pump.

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