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).
The engagement issues of starter motor gears and methods of chamfering.
| Identifier | WestWitteringFiles\T\2July1928-December1928\ Scan277 | |
| Date | 20th December 1928 | |
| A.{Mr Adams} FROM R.{Sir Henry Royce} C. to HJ. HS.{Lord Ernest Hives - Chair} (crossed out) EFC. ORIGINAL STARTER MOTOR ENGAGEMENT. EL/M20.12.28. X7625/B We have always been impressed that with the conventional method of chamfering starter gear teeth, even if applied to both the pinion and the gear ring on flywheel, there is a definite and considerable period during which blockage of engagement takes place. FIG: 1. .050" The usual method of chamfering is somewhat as shewn in fig. 1. in which a narrow band about .050" wide of the original end face of the tooth is left to form the leading edge. FIG: 2. If the body of the tooth be washed out the front face of gear then appears as shewn in fig. 2. as a number of curved facial edges spouting from the rim of the wheel. If now the engaging edges of the pinion and flywheel gear teeth respectively were always parallel the blocking period would be limited to the width of the leading edges of the teeth. They are however disposed radially round different centres with the result that engagement can be impeded over a more extended period as illustrated in fig. 3. FIG: 3. (1) | ||