One of the current research activities here at California State University at Fullerton is systematization of existing knowledge of design of planetary gear trains.

The bevel gear grinding process, with conventional wheels, has been limited to applications where the highest level of quality is required.

Up until approximately 1968-69, pinion cutter-type gear shaping machines had changed very little since their conception in the early 1900's.

This paper presents two new techniques for aligning and maintaining large ring gears. One technique uses lubricant temperature analysis, and the other uses stop action photography.

Hobbing is probably the most popular gear manufacturing process. Its inherent accuracy and productivity makes it a logical choice for a wide range of sizes.

Your May/June issue contains a letter from Edward Ubert of Rockwell International with some serious questions about specifying and measuring tooth thickness.

The effect of load speed on straight and involute tooth forms is studied using several finite-element models.

The fundamental purpose of gear grinding is to consistently and economically produce "hard" or "soft" gear tooth elements within the accuracy required by the gear functions. These gear elements include tooth profile, tooth spacing, lead or parallelism, axial profile, pitch line runout, surface finish, root fillet profile, and other gear geometry which contribute to the performance of a gear train.

As we approach the problem of hard gear processing, it is well to take a look at the reason for discussing it at this time. In our present economic atmosphere throughout the world, more and more emphasis is being placed upon efficiency which is dictated by higher energy costs.

The gear hobbing process is a generating type of production operation. For this reason, the form of the hob tooth is always different from the form of the tooth that it produces.