High-pressure common rail pump high reliability and long service life single-way check valve

Abstract

The invention provides a high-pressure common rail pump high reliability and long service life single-way check valve which comprises an oil outlet hole, a spring base, a returning spring and a sealing ball, wherein a sliding guiding sleeve is additionally arranged between the returning spring and the sealing ball, the right end surface of the sliding guiding sleeve is provided with a ball body supporting surface, a reset oil hole in the bottom of the ball body supporting surface is communicated with a spring limit hole, a side surface oil inlet channel is arranged on the cone surface of a cone segment, the side surface oil inlet channel is communicated with the spring limit hole, and the sealing ball, the sliding guiding sleeve, the returning spring and the spring base are sequentially arranged inside the oil outlet hole. The sealing ball is in sealing contact with a sealing cone surface under the centering supporting of the ball body supporting surface under the effect of the returning spring, and an opening and closing distance of the check valve is axially formed between the sliding guiding sleeve and the spring base. The sealing ball is supported by the ball body supporting surface in the moving process in a centering mode, the sealing ball can guide and cannot be damaged, the sealing belt formed between the sealing ball and the sealing cone surface is stable and reliable, the flowing back of high pressure oil can be prevented, and the high-pressure oil supply performance and the service life of a common rail pump are improved.

Description

Technical field: [0001] The invention relates to a hydraulic component in a hydraulic system, in particular to a hydraulic check valve in a common rail pump assembly of a high-pressure common rail system of a diesel engine. Background technique: [0002] With the progress of society and the enhancement of environmental protection awareness, people’s requirements for energy saving and emission reduction of diesel engines are getting higher and higher. At present, China’s diesel engines have implemented Euro IV emission standards, and the mechanically controlled fuel injection systems previously commonly used in China cannot meet the above requirements. Requirements: According to the design requirements of the diesel engine high-pressure common rail fuel injection supply system, the fuel injection pressure must be above 160Mpa. Through the common rail injector, timing, quantitative and precise injection to the corresponding combustion chamber of the diesel engine, so as to ensure th...

AI Technical Summary

Problems solved by technology

[0006]First, the sealing ball 93 is not guided during the retraction process. Due to reasons such as bending and tremor after the return spring 92 is compressed, the sealing ball 93 is in contact with the sealing ball. The first contact point of the conical surface 52 is not on the sealing ring, and a gap is formed between the sealing ball 93 and the sealing conical surface 52 for a short time, causing the high-pressure fuel in the common rail pipe to flow back instantaneously, resulting in insufficient fuel supply of the common rail pump

[0007]Secondly, the sealing ball 93 hitting the sealing cone surface 52 irregularly for a long time with high frequency will destroy both the sealing cone surface 52 and the sealing surface of the sealing ball 93 , resulting in seal failure;

[0008]Third, the stroke of the sealing ball 93 is not mechanically limited, and the compression of the return spring 92 may occur and cause the sealing ball 93 to fail to reset and seal the cone surface 52 fit, resulting in seal failure;

[0009] Fourth, since the end faces of the return spring 92 need to be ground, there are sharp edges and cutting edges at the heads of the steel wires at both ends of the return spring 92, The sealing ball 93 is constantly in contact with the sharp edges and cutting edges at both ends of the return spring 92, which will scratch or cut the surface of the sealing ball 93, and cause scratches or grooves on the sealing surface of the sealing ball 93, thereby causing the seal to fail

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