Internal Gears

GEAR TALK WITH CHUCK | 2018-07-03

Planetary Gears: Inside Information

The Story So Far

GEAR TALK WITH CHUCK | 2018-06-28

Suns and Planets

The first planetary drive I helped take apart had three stages of through hardened spur gears encased in a simple cast iron tube with plates on both ends. Both input and output shafts rotated on taper roller bearings, but everything else had simple bronze bushings.

GEAR TALK WITH CHUCK | 2017-02-14

Faster is Not Always Better

That old “Overhead” article reminded me of what a shock it was when we first moved into cellular manufacturing. After years of investigating ways t...

FEATURE ARTICLES | 2016-08-01

IMTS 2016 Booth Previews

Comprehensive descriptions of what you will find in the booths of many leading gear industry suppliers at IMTS 2016.

FEATURE ARTICLES | 2015-01-01

Getting in Gear with the Chain of Innovations

At the dawn of the Industrial Revolution, so-called mechanics were tasked with devising the precise methods that would make mass production possible. The result was the first generation of machine tools, which in turn required improved tooling and production methods.

ASK THE EXPERT | 2014-08-01

Importance of Contact Pattern in Assembly of Bevel vs Cylindrical Gears

Why is there so much emphasis on the tooth contact pattern for bevel gears in the assembled condition and not so for cylindrical gears, etc?

TECHNICAL ARTICLES | 2012-10-01

Center Distance Variations for Internal Gears

While external involute gears are very tolerant of center distance variations, what are the center distance constraints for internal gears?

TECHNICAL ARTICLES | 2012-06-01

FZG Rig-Based Testing of Flank Load-Carrying Capacity Internal Gears

Micropitting, pitting and wear are typical gear failure modes that can occur on the flanks of slowly operated and highly stressed internal gears. However, the calculation methods for the flank load-carrying capacity have mainly been established on the basis of experimental investigations of external gears. This paper describes the design and functionality of the newly developed test rigs for internal gears and shows basic results of the theoretical studies. It furthermore presents basic examples of experimental test results.

INDUSTRY NEWS | 2006-04-30

Sterling Instruments New Precision Internal Gears Selectable by Inches or Millimeters

New precision internal gears from Sterling Instrument are available from stock in inch and metric sizes. The 20? pressure angle inch ...

TECHNICAL ARTICLES | 2006-01-01

Investigation of the Noise and Vibration of Planetary Gear Drives

With the aim of reducing the operating noise and vibration of planetary gear sets used in automatic transmissions, a meshing phase difference was applied to the planet gears that mesh with the sun and ring gears.

INDUSTRY NEWS | 2005-04-13

New North American Subsidiary for Atlanta GmbH

Atlanta GmbH in Bietingheim-Bissingen, Germany, announced the formation of its new North American subsidiary, Atlanta Drive Systems Inc.,...

TECHNICAL ARTICLES | 1990-05-01

The Geometric Design of Internal Gear Pairs

The paper describes a procedure for the design of internal gear pairs, which is a generalized form of the long and short addendum system. The procedure includes checks for interference, tip interference, undercutting, tip interference during cutting, and rubbing during cutting.

TECHNICAL ARTICLES | 1989-07-01

On The Interference of Internal Gearing

Since size and efficiency are increasingly important considerations in modern machinery, the trend is gear design is to use planetary gearing instead of worm gearing and multi-stage gear boxes. Internal gearing is an important part of most of planetary gear assemblies. In external gearing, if the gears are standard (of no-modified addenda), interference rarely happens. But in an internal gearing, especially in some new types of planetary gears, such as the KHV planetary, the Y planetary, etc., (1) various types of interference may occur. Therefore, avoiding interference is of significance for the design of internal gearing.

PUBLISHER'S PAGE | 1989-01-01

Leonardo, the Engineer

These lines, interesting enough, are from the notebooks of an artist whose images are part of the basic iconography of Western culture. Even people who have never set foot in a museum and wouldn't know a painting by Corregio from a sculpture by Calder, recognize the Mona Lisa. But Leonardo da Vinci was much more than an artist. He was also a man of science who worked in anatomy, botany, cartography, geology, mathematics, aeronautics, optics, mechanics, astronomy, hydraulics, sonics, civil engineering, weaponry and city planning. There was little in nature that did not interest Leonardo enough to at least make a sketch of it. Much of it became a matter of lifelong study. The breadth of his interests, knowledge, foresight, innovation and imagination is difficult to grasp.

EVENTS | 1988-11-01

Technical Calendar

November 1-3. SME Gear Processing and Manufacturing Clinic, Sheraton Meridian, Indianapolis, IN. November 5-10. international Conference on Gearing, Zhengzhou, China

TECHNICAL ARTICLES | 1988-09-01

Crowned Spur Gears: Optimal Geometry and Generation

Involute spur gears are very sensitive to gear misalignment. Misalignment will cause the shift of the bearing contact toward the edge of the gear tooth surfaces and transmission errors that increase gear noise. Many efforts have been made to improve the bearing contact of misaligned spur gears by crowning the pinion tooth surface. Wildhaber(1) had proposed various methods of crowning that can be achieved in the process of gear generation. Maag engineers have used crowning for making longitudinal corrections (Fig. 1a); modifying involute tooth profile uniformly across the face width (Fig. 1b); combining these two functions in Fig. 1c and performing topological modification (Fig. 1d) that can provide any deviation of the crowned tooth surface from a regular involute surface. (2)

TECHNICAL ARTICLES | 1988-05-01

Computer-Aided Design of the Stress Analysis of an Internal Spur Gear

Although there is plenty of information and data on the determination of geometry factors and bending strength of external gear teeth, the computation methods regarding internal gear design are less accessible. most of today's designs adopt the formulas for external gears and incorporate some kind of correction factors for internal gears. However, this design method is only an approximation because of the differences between internal gears and external gears. Indeed, the tooth shape of internal gears is different from that of external gears. One has a concave curve, while the other has a convex curve.

TECHNICAL ARTICLES | 1988-01-01

The Use of Boundary Elements For The Determination of the AGMA Geometry Factor

The geometry factor, which is a fundamental part of the AGMA strength rating of gears, is currently computed using the Lewis parabola which allows computation of the Lewis form factor.(1) The geometry factor is obtained from this Lewis factor and load sharing ratio. This method, which originally required graphical construction methods and more recently has been computerized, works reasonably well for external gears with thick rims.(2-6) However, when thin rims are encountered or when evaluating the strength of internal gears, the AGMA method cannot be used.