Outer rings to planetary gears

The outer rings of planetary gears are often considered to be difficult to manufacture. The reasons are that you often need very expensive tools to manufacture the rings and complex holders or fixtures, since distortions during heat treatment is often a serious problem in gear manufacturing. The goal for this hypothesis project is to improve the manufacturing of outer rings to planetary gears by studying the design of the rings in order to ease the manufacturing and to study the possibility to use loose teeth in the outer rings.

Since outer rings of planetary gears are both difficult and expensive to manufacture we want to study the possibility to manufacture the rings more efficient. Today we often need complex  tools in order to suceed with the manufacturing. Alternative design of the outer rings and/or alternative gear teeth form is perhaps a possibility to make the manufacturing more efficient. We also will study the possibility to use lose gear teeth in order to keep performance/precision and thereby prevent difficult form errors during heat treatment. This solution is used in robots for industry. The gear teeth are then cylindrical pins, which probably are pressed into particular growes in the ring.

In order to reach the goals this work is divided into the following moment: 1.Analysis of the manufacturing of planetary gears. 2.Study if it is possible to manufacture alternative outer rings more efficient. 3.Study if lose teeth can be an interesting solution. 4.Make and functionally test a planetary gear with lose teeth.  5.Make a general investigation of the patent situation.