Simulative Analysis of Piston Posture and Piston/Cylinder Interface Leakage of EHA Pumps by the Influence of Rotating Speed

doi:10.3901/JME.2018.20.123

Abstract

Abstract: As the significant component of EHA(electro-hydrostatic actuator), bent-axis type piston pumps can realize miniaturization and light quantification by high rotating speed and high working pressure. Piston/cylinder pair is one of the two important friction pairs of bent-axis type piston pumps, which directly affects the working condition of the pump. As the cylinder rotating, the posture of the piston in the cylinder bore is changing in all directions constantly, and the leakage flow of piston/cylinder interface is changing. So the aim of this paper is to get the leakage flow of piston/cylinder interface in high speed and high pressure accurately and offer the explanation. The force on the piston is fully taken into account, disperse the Reynolds equation of the Piston/cylinder pair oil film and iterative solve the force/moment equation, get the offset of the piston end faces to exactly describe the posture of the piston in the cylinder bore with rotating speed changing, the model of piston/cylinder interface leakage flow is given on the base, and analyzed the piston/cylinder interface leakage by the influence of rotating speed. The conclusion provides the appropriate theoretical guidance when design EHA pumps.

Key words: bent-axis axial piston pumps, electro-hydrostatic actuator(EHA), leakage, piston-cylinder pair, posture

CLC Number:

TH137

LÜ Fei, XU Bing, ZHANG Junhui. Simulative Analysis of Piston Posture and Piston/Cylinder Interface Leakage of EHA Pumps by the Influence of Rotating Speed[J]. Journal of Mechanical Engineering, 2018, 54(20): 123-130.

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