The last two months have been both a time of difficulty and of growth for Gear Technology. Unexpectedly, I found myself in the hospital having surgery, and consequently out of commission for several weeks. At the same time, two individuals on our staff lost family members, and most of this period saw us getting ready for this preshow IMTS issue while being seriously short-staffed.
Below are listed a variety of commonly used constants arranged numerically to permit ease of reference. Wherever an asterisk (*) is shown, the constant is exact as given, it being generally a mathematical constant or one fixed by definition. In cases where the first constant listed is followed by another in parenthesis, the first is the round number generally used, while the second is the more exact value.
Gears are currently run at high speed and under high load. It is a significant problem to develop lubricants and gears with high load-carrying capacity against scoring. The particles of molybdenum disulfide have been considered to increase the scoring resistance of the gears. The wear characteristics and the scoring resistance of the gears lubricated with MoS2 paste and MoS2 powder have been investigated. (1) However, there are few investigations on the performance of the gears coated with MoS2 film with respect to scoring.
Mechanical efficiency is an important index of gearing, especially for epicyclic gearing. Because of its compact size, light weight, the capability of a high speed ratio, and the ability to provide differential action, epicyclic gearing is very versatile, and its use is increasing. However, attention should be paid to efficiency not only to save energy, but sometimes also to make the transmission run smoothly or to avoid a self-locking condition.
Since we are a high volume shop, we were particularly interested in Mr. Kotlyar's article describing the effects of hob length on production efficiency which appeared in the Sept/Oct issue of Gear Technology. Unfortunately, some readers many be unnecessarily deterred from applying the analysis to their own situations by the formidabilty of the mathematical calculations. I am making the following small suggestion concerning the evaluation of the constant terms.
September 3-11 the 1986 International Machine Tool Show, "The World of Manufacturing Technology", will be held at the McCormick Place Exposition Center in Chicago. More that 1000 exhibits from over thirty countries are planned. These exhibits will present a complete range of machine-tool products from 2-story high presses to complete manufacturing systems, lathes, lasers, CAD/CAM systems and robotics.
October 5-8, 1986 AGMA Fall technical Conference & Gearing Exhibit
September 17-19, 1986 Ohio State University Gear Noise Seminar
November 11-13, 1986 SME Gear Processing and Manufacturing Clinic
November 19-21, 1986 Seminar: Gear System Design for Minimum Noise
The most conclusive test of bevel and hypoid gears is their operation under normal running conditions in their final mountings. Testing not only maintains quality and uniformity during manufacture, but also determines if the gears will be satisfactory for their intended applications.