Electro-hydrostatic actuator （EHA） pumps are usually characterized as high speed and small displacement. The tilting inertia moment on the cylinder block produced by the inertia forces of piston/slipper assemblies c...Electro-hydrostatic actuator （EHA） pumps are usually characterized as high speed and small displacement. The tilting inertia moment on the cylinder block produced by the inertia forces of piston/slipper assemblies cannot be ignored when analyzing the cylinder block balance. A large tilting inertia moment will make the cylinder block tilt away from the valve plate, resulting in severe wear and significantly increased leakage. This paper presents an analytical expression for the tilting inertia moment on the cylinder block by means of vector analysis. In addition, a high-speed test rig was built up, and experiments on an EHA pump prototype were carried out at high speeds of up to 10,000 r/min. The predicted nature of the cylinder block tilt at high speeds corresponds closely to the witness marks on the dismantled EHA pump prototype, It is suggested that more attention should be given to the tilting inertia moment acting on the cylinder block of an EHA pump since both wear and leakage flow between the cylinder block and the valve plate are very much dependent on this tilting moment.展开更多
Increasing the rotating speed is considered as an efficient approach to upgrade the power-to-weight ratio in an axial piston pump,but penalized by more leakage and more severe wear resulting from the adverse cylinder ...Increasing the rotating speed is considered as an efficient approach to upgrade the power-to-weight ratio in an axial piston pump,but penalized by more leakage and more severe wear resulting from the adverse cylinder block tilt.Previous studies mainly focused on the bearing characteristic of the valve plate/cylinder block pair,but the spline coupling also plays a key role in the undesired cylinder block tilt,which has been little studied.A theoretical model for the rotating assembly is presented to investigate the effect of the spline coupling length on the cylinder block tilt and the performance of the valve plate/cylinder block pair.A typical high-speed axial piston pump with the displacement of 5.2 mL/r at 10000 r/min was studied by simulation and experiment.It shows that the optimal spline coupling length is one value increased by 2 mm from the original,bringing a remarkable leakage reduction under the high-speed condition by decreasing the cylinder block tilting angle.The experiment result matches well with the simulation.The influences of the spline coupling on the cylinder block tilt and the leakage were demonstrated.展开更多
基金the National Basic Research Program of China(No.2014CB046403)the National Natural Science Foundation of China(No.U1509204)for their financial supports
文摘Electro-hydrostatic actuator （EHA） pumps are usually characterized as high speed and small displacement. The tilting inertia moment on the cylinder block produced by the inertia forces of piston/slipper assemblies cannot be ignored when analyzing the cylinder block balance. A large tilting inertia moment will make the cylinder block tilt away from the valve plate, resulting in severe wear and significantly increased leakage. This paper presents an analytical expression for the tilting inertia moment on the cylinder block by means of vector analysis. In addition, a high-speed test rig was built up, and experiments on an EHA pump prototype were carried out at high speeds of up to 10,000 r/min. The predicted nature of the cylinder block tilt at high speeds corresponds closely to the witness marks on the dismantled EHA pump prototype, It is suggested that more attention should be given to the tilting inertia moment acting on the cylinder block of an EHA pump since both wear and leakage flow between the cylinder block and the valve plate are very much dependent on this tilting moment.
基金This study was co-supported by the National Key R&D Program of China(No.2019YFB2005101)National Outstanding Youth Science Foundation of China(No.51922093)+2 种基金the National Natural Science Foundation of China(No.52105075)the National Natural Science Foundation of China(No.51890882)the Natural Science Foundation of Zhejiang Province(No.LQ21E050022).
文摘Increasing the rotating speed is considered as an efficient approach to upgrade the power-to-weight ratio in an axial piston pump,but penalized by more leakage and more severe wear resulting from the adverse cylinder block tilt.Previous studies mainly focused on the bearing characteristic of the valve plate/cylinder block pair,but the spline coupling also plays a key role in the undesired cylinder block tilt,which has been little studied.A theoretical model for the rotating assembly is presented to investigate the effect of the spline coupling length on the cylinder block tilt and the performance of the valve plate/cylinder block pair.A typical high-speed axial piston pump with the displacement of 5.2 mL/r at 10000 r/min was studied by simulation and experiment.It shows that the optimal spline coupling length is one value increased by 2 mm from the original,bringing a remarkable leakage reduction under the high-speed condition by decreasing the cylinder block tilting angle.The experiment result matches well with the simulation.The influences of the spline coupling on the cylinder block tilt and the leakage were demonstrated.
