Epicyclic Gear Systems: Application, Design and Analysis - December 3-5, 2019

Expected Student Learning (Course Level) Outcomes:

Calculate the total reduction ratio of an epicyclic system and that of a star system.

Restate exactly what makes a gear system an epicyclic system 

Identify differences and similarities between split power systems and true epicyclic systems.

Recognize when the use of a star drive system is preferred over a planetary system.

Understand the importance of equal planet/star gear spacing and how a system be designed with unequal planet spacing.

Interpret how the numbers of teeth selected for the individual gears in an epicyclic or star drive gear system affect the noise and vibration characteristics of the system.

Identify are the advantages of selecting odd numbers of teeth for the planet/star gears?

Evaluate the numbers of teeth on the sun, planet and internal ring gear not arbitrary and what are the relations that must be maintained among these tooth numbers and why

Explain how the design of the carrier affects the overall performance of these complex systems

Determine how does input speed affect the design of an epicyclic system and why are the speed concerns different for epicyclic and star drive systems

Restate how the selection of the “fixed” member in a planetary system affect the ratio and relative rotation directions of the input and output shafts?

Understand the design and use of load balancing systems including floating sun gears, and floating ring gears.

2.0 CEUs


Raymond Drago, P.E.

Chief Engineer - Gear Technologist, Drive Systems Technology

Raymond J. Drago is Chief Engineer of Drive Systems Technology, Inc. (DST), a mechanical power transmission consulting organization that he founded in 1976. Prior to this, Mr. Drago worked for the Boeing Company – Helicopters Division until his retirement after 37 years of service. Currently Mr. Drago is involved in the analysis, design, manufacture, assembly, and testing of many gear systems. In his role with DST, Mr. Drago is active in all areas of mechanical power transmission, including the design and analysis of drive systems in a very diverse field of application from heart pumps to very large mining & mill gears. He has also prepared and delivered more than 150 seminars dealing with various aspects of gear design and analysis.

Steve Cymbala

Senior Drives Engineer

Steve Cymbala has served as Senior Drives Engineer for Drive Systems Technology, Inc. for more than 40 years. In this capacity, Steve performs gearbox design functions as well as client drawing reviews prior to placement of orders. He performs field gearbox failure investigations as well as witnessing various Non-Destructive Examination inspections at gear manufacturing facilities on behalf of DST, Inc. clients. Steve was an employee of the Boeing Company for 34 years where he held a position of Staff Engineer.

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