Estimation of reliability of devices of control of speed changes through gear differentials on the basis of their energy efficiency

Abstract

The theoretical study of the reliability of devices for speed change by gear differentials with closed circuit hydrosystems have been held, based on energy efficiency of such devices, defining efficiency coefficient. The analytical expressions have been obtained for determining the efficiency coefficient of the gear differential of the speed change device with various combinations of driving, driven and control links. To solve this problem, potential power method have been used, based on the frictional losses in each wheel engagement. These losses are proportional to the product of the circular force on the teeth and the velocity of the point on the satellite’s initial circle in relation to the carrier, or the product of the torque from this force and angular velocity. Using computer simulation of analytical expressions, using the MS Excel software package, the graphical dependencies of the performance efficiency from the gear ratio and the angular velocity of the control link – either sun gear, or ring gear or carrier, have been obtained. The example of the graphs have been given for the case when the driving element is a sun gear, driven is a carrier, and the ring gear controls the speed change. The obtained graphic dependences for the performance efficiency of the gear differentials graphically allow you to follow the change in the value of the efficiency, depending on the angular velocity of the control link and the gear ratio. This allows us to evaluate the perfection of a speed change device with gear differential and closed circuit hydrosystem in terms of energy consumption and possible self-braking, and also derive the conclusion about its reliability. The results obtained have practical application at the stage of development and when designing new speed control devices through the sun gear and provide the basis for further research. Recommended for implementation in engineering practice during the design of new speed changing devices through the gear differentials of drives of various techniques and in the educational process of higher technical schools in the discipline of machine science in the study of machine drives at the engineering disciplines in higher educational establishments.