Dynamics of early planetary gear trains

A method to analyze the static and dynamic loads in a planetary gear train was developed. A variable-variable mesh stiffness (VVMS) model was used to simulate the external and internal spur gear mesh behavior, and an equivalent conventional gear train concept was adapted for the dynamic studies. The analysis can be applied either involute or noninvolute spur gearing. By utilizing the equivalent gear train concept, the developed method may be extended for use for all types of epicyclic gearing. The method is incorporated into a computer program so that the static and dynamic behavior of individual components can be examined. Items considered in the analysis are: (1) static and dynamic load sharing among the planets; (2) floating or fixed Sun gear; (3) actual tooth geometry, including errors and modifications; (4) positioning errors of the planet gears; (5) torque variations due to noninvolute gear action. A mathematical model comprised of power source, load, and planetary transmission is used to determine the instantaneous loads to which the components are subjected. It considers fluctuating output torque, elastic behavior in the system, and loss of contact between gear teeth. The dynamic model has nine degrees of freedom resulting in a set of simultaneous second order differential equations with time varying coefficients, which are solved numerically. The computer program was used to determine the effect of manufacturing errors, damping and component stiffness, and transmitted load on dynamic behavior. It is indicated that this methodology offers the designer/analyst a comprehensive tool with which planetary drives may be quickly and effectively evaluated

Report on model study of a trapezoidal flume for measurement of stream discharge

CER59ARR57.January 1960.Prepared for the Rocky Mountain Forest and Range Experiment Station.Includes bibliographical references

Orifice plates for furrow flow measurement

CER59ARR24.December 7, 1959.Research Report No. 323.At the request of the Soil Conservation Service, Western Soil and Water Management Research Branch, Soil and Water Conservation Research Division, Agricultural Research Service, United States Department of Agriculture

Annual report, 1956

CER56AAR18.Includes bibliographical references

Flow measurement in open channels

CER62ARR-ARC4.Paper to be presented at National Meeting, American Society of civil Engineers, Houston, Texas, Feb. 19-23, 1962.Joint contribution from Colorado State University and the Soil and Water Conservation Research Division, Agricultural Research Service, U.S. Dept. of Agriculture, Fort Collins, Colorado

Measuring seepage from irrigation channels

CER59-47.Literature cited: pages 81-82.6 folded charts in pocket

Interceptor drains

CER 58 ARR 32.September 1955.Includes bibliographical references.A contribution from the Western Soil and Water Management Research Branch, ARS, and Colorado Agricultural Experiment Station, Fort Collins, Colo

Discussion of Unification of Parshall flume data

CER62ARR21

Dynamic effects of internal spur gear drives

Static analysis, dynamic analysis, and computer programs are discussed. Spur gear formulae and involute profile development and deflection are also discussed