Stringent NVH requirements, higher
loads and the trend towards miniaturization to save weight and space are forcing transmission gear designers to increasingly tighten the surface finish, bore size and bore-to-face perpendicularity
tolerances on the bores of transmission
gears.
It’s happened to most manufacturers at one point or another. A defective
product comes back from a customer in
need of repair. Perhaps a bearing or a
gear drive has failed, and the customer
simply needs a replacement. Upon further
examination, the company realizes it was never one of its products in the
first place, but a fabricated copy that
snuck into the market. The manufacturing
community has been dealing with
counterfeit products for decades, but
used machinery dealers and Internet
shoppers seem to continuously get hit
by scam artists.
In this paper, the potential for geometrical cutting simulations - via penetration calculation to analyze and predict tool wear as well as to prolong tool life - is shown by means of gear finish hobbing. Typical profile angle deviations that occur with increasing
tool wear are discussed. Finally, an approach is presented here to attain improved profile accuracy over the whole tool life of the finishing hob.
Easily one of the central issues
affecting U.S. manufacturing is what one might call the exports deficit—the inability of American companies to sell products to, for instance, Asian markets, developing countries and other ports of call—due to what they perceive to be unfair trade agreements and or policies.
The machine element package by KISSsoft for the design and optimization of components like gears, shafts, bearings and others is now available in the new version 04/2010.
This paper shows an experimental study on the fatigue lifetime of high-heat polyamide (Stanyl) gears running in oil at 140°C. Based on previous works (Refs. 1–2), an analysis is made correcting for tooth bending and calculating actual root stresses. A comparison with tensile bar fatigue data for the same materials at 140°C shows that a good correlation exists between gear fatigue data and tensile bar fatigue data. This insight provides a solid basis for gear
designers to design plastic gears using actual material data.
Several innovations have been introduced to the gear manufacturing industry in recent years. In the case of gear hobbing—the dry cutting technology and the ability to do it with powder-metallurgical HSS—might be two of the most impressive ones. And the technology is still moving forward. The aim of this article is to present recent developments in the field of gear hobbing in conjunction with the latest improvements regarding tool materials, process technology
and process integration.