Behavior Of Gear System Research Articles

Vibration characteristics of spur gear system with non-linear damping under no lubrication condition

Gear rattle induced by backlash between meshing gears results in excessive vibration and noise in many gear systems. A dynamic model of a light-loaded spur gear pair with non-linear damping under no lubrication condition is presented in this paper. Unlike previous models, the effect of backlash on damping is considered, so the damping is not linear. In order to illustrate the effect of non-linear damping on the dynamic response, the dynamic behaviors of gear system with non-linear damping (GSND) and linear damping (GSLD) under different impact status are compared by using the numerical integration method. The results show that the behavior of gear pair with non-linear damping is different from that with linear damping, and the impact vibration of GSND is much greater than GSLD under some conditions. The influences of parameters such as load ratio, load value, meshing stiffness, and damping ratio on the dynamic responses of GSND are also discussed, and some suggestions to reduce impact vibration of gear system are proposed. The results provide a theoretical basis for the design and manufacture of gear system.

Global behavior of gear system using mixed cell mapping

In some mechanical nonlinear systems, the transient motion will be undergoing a very long process and the attractor-basin boundaries are so complicated that some difficulties occur in analyzing the system global behavior. To solve this problem a mixed cell mapping method based on the point mapping and the principle of simple celll mapping is developed. The algorithm of the mixed cell mapping is studied. A dynamic model of a gear pair is established with the backlash, damping, transmission error and the time-varying stiffness taken into consideration. The global behaviors of this system are analyzed. The coexistence of the system attractors and the respective attractor-basin of each attractor with different parameters are obtained, thus laying a theoretical basis for improvement of the dynamic behaviors of gear system.

Dynamic Behavior of Gear Systems and Variation of Coefficient of Friction and Efficiency During the Engagement Cycle

In this work, the instantaneous and average efficiency and coefficient of friction of gear drives operating at low, medium, and moderately high speeds were experimentally and analytically investigated. First, using the gear testing machine specially designed for this type of investigation, the frictional losses in gearing during the engagement period were obtained experimentally. Based upon the obtained data, the values of efficiency and coefficient of friction were evaluated. A mathematical model simulating the gear testing machine was then developed and employed for the analysis of the dynamic behavior of the gear train system and analytical evaluation of gear system efficiency. The results obtained from this model were compared to those obtained directly from experiments, and a close correlation was achieved. The influence of such factors as diametral pitch, contact ratio, magnitude of transmitted load, and speed upon the efficiency of gear drives and the coefficient of friction in gearing was investigated. This investigation showed that the suggested method may be used to predict the dynamic behavior and efficiency of gear systems if a coefficient of friction is known or assumed. This investigation also gives some promise for power gear transmission design with improved capacity when scoring is the limiting criterion for capacity.

Closure to “Discussion of ‘Dynamic Behavior of Gear Systems and Variation of Coefficient of Friction and Efficiency During the Engagement Cycle’” (1975, ASME J. Eng. Ind., 97, p. 1280)

Closure to “Discussion of ‘Dynamic Behavior of Gear Systems and Variation of Coefficient of Friction and Efficiency During the Engagement Cycle’” (1975, ASME J. Eng. Ind., 97, p. 1280)

Discussion: “Dynamic Behavior of Gear Systems and Variation of Coefficient of Friction and Efficiency During the Engagement Cycle” (Radzimovsky, E., and Mirarefi, A., 1975, ASME J. Eng. Ind., 97, pp. 1274–1280)

Discussion: “Dynamic Behavior of Gear Systems and Variation of Coefficient of Friction and Efficiency During the Engagement Cycle” (Radzimovsky, E., and Mirarefi, A., 1975, ASME J. Eng. Ind., 97, pp. 1274–1280)