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).
Trials on a pinion for a sequence starter, observing jamming faults and comparing it to a Bosch design.
| Identifier | WestWitteringFiles\T\2January1929-June1929\ Scan120 | |
| Date | 7th February 1929 | |
| To R.{Sir Henry Royce} from EFC. c. SG.{Arthur F. Sidgreaves - MD} E.{Mr Elliott - Chief Engineer} c. Wor.{Arthur Wormald - General Works Manager} By.{R.W. Bailey - Chief Engineer} ORIGINAL EFC2/T7.2.29. SS.{S. Smith} SEQUENCE STARTER. X7625 X4562 We will arrange to make a trial of a pinion with all corners rounded. We have, however, considerable hope that the backed-off pinion, which we are at present awaiting, will eliminate the jamming faults we have experienced. We have made, and are making, on our rig, systematic observations of engagement by gradually reducing the supply voltage until the first fault occurs. Alternately we allow the main current to come on and rotate the crankshaft (on the other end of which we have a brake wheel and brake) and then prevent the main current coming on by opening the switching circuit which is normally closed by the motion of the motor armature. The results of these tests will be reported in due course. In regard to your query respecting what Bosch does with his pinion teeth, these are left sharp on both sides with the exception of a very small chamfer. It is however to be remembered that in the Bosch case the motor is adapted, by comparatively simple changes in the electrical connections, to run in either direction as required. Therefore, the pinion teeth are symmetrical forwards and backwards which includes the fact of being parallel. An impression of the profile of the Bosch teeth accompanies this note. Contd. | ||