May/June 2001

Core Competency

May 1, 2001

Rodgers and Hammerstein produced some of America's most memorable and lasting songs in musical theater. Lyricist Oscar Hammerstein II once said of composer Richard Rodgers, "I hand him a lyric and get out of his way," Hammerstein knew what Rodgers was good at, and vice versa, and each trusted his partner. Their partnership was so successful that you can scarcely think of one man without the other.

Taking On Nature: Three Gear Companies And Their End-Products

May 1, 2001

Many gear companies make parts, build assemblies...and stop there. But, some don't stop; they go a step further and create end-products. Three gear companies have taken that step, and taken on nature with their creations.

Load Distribution in Planetary Gears

May 1, 2001

Two-shaft planetary gear drives are power-branching transmissions, which lead the power from input to output shaft on several parallel ways. A part of the power is transferred loss-free as clutch power. That results in high efficiency and high power density. Those advantages can be used optimally only if an even distribution of load on the individual branches of power is ensured. Static over-constraint, manufacturing deviations and the internal dynamics of those transmission gears obstruct the load balance. With the help of complex simulation programs, it is possible today to predict the dynamic behavior of such gears. The results of those investigations consolidate the approximation equations for the calculation of the load factors...

Design Formulas for Evaluating Contact Stress in Generalized Gear Pairs

May 1, 2001

David B. Dooner

A very important parameter when designing a gear pair is the maximum surface contact stress that exists between two gear teeth in mesh, as it affects surface fatigue (namely, pitting and wear) along with gear mesh losses. A lot of attention has been targeted to the determination of the maximum contact stress between gear teeth in mesh, resulting in many "different" formulas. Moreover, each of those formulas is applicable to a particular class of gears (e.g., hypoid, worm, spiroid, spiral bevel, or cylindrical - spur and helical). More recently, FEM (the finite element method) has been introduced to evaluate the contact stress between gear teeth. Presented below is a single methodology for evaluating the maximum contact stress that exists between gear teeth in mesh. The approach is independent of the gear tooth geometry (involute or cycloid) and valid for any gear type (i.e., hypoid, worm, spiroid, bevel and cylindrical).

Gearbox Field Performance From a Rebuilder's Perspective

May 1, 2001

Charles D. Schultz

The major focus of the American Gear Manufacturers Association standards activity has been the accurate determination of a gearbox's ability to transmit a specified amount of power for a given amount of time. The need for a "level playing field" in the critical arena was one of the reasons the association was formed in the first place. Over the past 85 years, AGMA committees have spent countless hours "discussing" the best ways to calculate the rating of a gear set, often arguing vigorously over factors that varied the resulting answers by fractions of a percentage point. While all that "science" was being debated in test labs and conference rooms all over the country, out industry's customers were conducting their own experiments through the daily operation of gear-driven equipment of all types.

Gear Fashion

May 1, 2001

Combining involute curves and body curves, merging factory and fashion, Winzeler Gear has transformed one of its products into gear haute couture. Winzeler Gear has created a plastic gear dress.

Product News

May 1, 2001

Complete Product News for May/June 2001.

Technical Calendar

May 1, 2001

Complete Technical Calendar for May/June 2001.

Industry News

May 1, 2001

Complete Industry News for May/June 2001.

Revolutions

May 1, 2001

Welcome to Revolutions, the column that brings you the latest, most up-to-date and easy-to-read information about the people and technology of the gear industry.

Calculating Dynamic Loads, Sizing Worm Gears and Figuring Geometry Factors

May 1, 2001

Robert Errichello

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