From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Analysis of the cause of jamming between pinion and wheel teeth due to the design of their corners.
| Identifier | WestWitteringFiles\T\2January1929-June1929\ Scan070 | |
| Date | 26th January 1929 guessed | |
| -2- Contd. The nature of the jam observed was immediately arrived at by noticing the fact that when the jam occurred the leading sharp corners of the pinion teeth were not presented to the following sharp corners of the wheel teeth at all, but that the rounded or disengaging corners of the pinion teeth were presented to the corresponding corners of the wheel teeth. The fact of the existence of a radius entered the wheel longitudinally, but in a enables the pinion to have slightly/later position angularly than it should be, the consequence being that the top surface of a wheel tooth, in attempting to enter between two pinion teeth, catches on the top of the pinion tooth just in advance of it, because the pinion tooth is a little late. The effectiveness of the jam of course depends upon the exact chance positional relation of the pinion to wheel and in some cases the application of an assisting turning moment to the wheel will free the wheel. In other cases, however, it is possible to apply a very big force to the wheel without clearing the jam, and as g big a force as would be quite unreasonable to expect from a teazer turning moment. This has been up to the present an unsuspected cause of jamming, but there is no doubt about the nature of this from the observations we have made, and it appears to result directly from the disengaging radius having been provided on both pinion and wheel teeth. Contd. | ||