scholarly journals Compensation of Input Shaft Torque on Indexing Cam Mechanisms. 3rd Report. Correction by Inertia Term for Compensating System with Deminaut Spring Force.

1994 ◽  
Vol 60 (576) ◽  
pp. 2830-2836 ◽  
Author(s):  
Masao Nishioka ◽  
Masatsugu Yoshizawa
Keyword(s):  
Inertia Term ◽  
Input Shaft ◽  
Spring Force ◽  
Shaft Torque

Torque Ripple Attenuation of an Axial Piston Pump by Continuous Swash Plate Adjustment

2005 ◽  
Author(s):  
Viral S. Mehta ◽  
Noah D. Manring
Keyword(s):  
Noise Level ◽  
Torque Ripple ◽  
Primary Objective ◽  
Piston Pump ◽  
Control Law ◽  
Axial Piston Pump ◽  
Input Shaft ◽  
Swash Plate ◽  
Shaft Torque ◽  
Axial Piston

One of the major drawbacks of a hydraulic system is the disturbing noise generated by the hydraulic pump. Based on the accepted theory about noise generation in an axial piston pump, various studies suggesting modification of the port-plate relief groove geometry and addition of hydraulic attenuators have shown a limited success in reducing the noise. The noise level is still high and may not be acceptable for future applications. A recent industrial study shows that the noise apparently has relation with the torque acting on the input shaft of the axial piston pump. The primary objective of this paper is to describe a new method to reduce the noise level by varying the swash plate of the pump continuously to eliminate the torque ripple. The paper begins by deriving the equation of torque acting on the input shaft as a function of the average torque and the total number of pistons that are used within the rotating group. A control law is derived according to which if the swash plate is dithered, should give a constant shaft torque. By attenuating the torque ripple characteristics of the pump, other vibrational aspects of the pump are also expected to be reduced. The secondary objective of this paper is to present a Simulink® model of a nine piston pump to describe a functional pump. The swash plate control law earlier derived will be applied to this model to see the behavior of the output parameters like the shaft torque, output flow and pressure. The results will be investigated to see if any relationship exist between the pump torque ripple and pressure ripple, and the theory of pump noise attenuation by reduction in torque ripple will be corroborated.

Modeling and Experimental Study of a Novel Power Split Hydraulic Transmission

2018 ◽  
Author(s):  
Haoxiang Zhang ◽  
Feng Wang ◽  
Bing Xu
Keyword(s):  
Flow Rate ◽  
Experimental Studies ◽  
Friction Torque ◽  
Output Shaft ◽  
Mechanical Power ◽  
Vane Pump ◽  
Input Shaft ◽  
Power Split ◽  
Outlet Flow ◽  
Shaft Torque

The characteristics of a novel power split hydraulic transmission are studied in this paper. The new hydraulic transmission is built from a balanced vane pump with a floating ring. By coupling the floating ring to the output shaft, it becomes a hydraulic transmission, converting the mechanical power on the input shaft into the hydraulic power at the outlet and the mechanical power on the output shaft. By controlling the pressure at the outlet (control pressure), the power ratio transferred through mechanical and hydraulic path can be adjusted. One important feature of the new transmission is that the internal friction torque of the transmission, e.g., friction torque between vane tips and floating ring, helps to drive the output shaft whereas is wasted and turned into heat in a conventional vane pump. This increases the transfer efficiency from input shaft to output shaft. In this study, the characteristics of the input shaft torque, output shaft torque and the outlet flow rate are investigated through experimental studies. Results show that the shaft torques and the outlet flow rate are functions of control pressure and differential shaft speed. The mathematical models have been developed from the analytical and experimental results. The study provides a comprehensive understanding of the new transmission.

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