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).
Report comparing two sequence starter schemes (No.1 and No.2A) and their performance regarding jamming.
| Identifier | WestWitteringFiles\R\2October1927-November-1927\ 179 | |
| Date | 26th November 1927 | |
| To R.{Sir Henry Royce} from EFC. c. BJ. E.{Mr Elliott - Chief Engineer} c. BY.{R.W. Bailey - Chief Engineer} ORIGINAL EFC4/T26.11.27. SEQUENCE STARTER. X7650 X7655 A/B In our EFC2/T26.8.27, which was the last report on the sequence starter No.1 scheme, we explained why we were of the opinion that in the avoidance of jamming in engagement the engaging corners of the teeth of the pinion and wheel should be as sharp as available material will allow. In the No.1 scheme as finally arranged on 9-EX with a 20° spiral, it is now very rare for a jam to occur; the entering corners of the teeth in this case are comparatively sharp. It was explained that it was possible to have a jam, and we did sometimes have such a case before we altered the angle of the helix. When a jam did occur, on releasing the push button the relative position of the pinion and wheel would not alter and the jam could not be usually cleared, except by using the starting handle. In the No.2A scheme which we have had up to the present on 14-EX, there has never been any necessity to use the starting handle, the reason being that the scheme is fundamentally better in the sense that if a jam does occur on the engaging corners of the teeth, on removal of the thumb from the press button, the armature movement under action of the spring allows the pinion to recede from the wheel and another chance is afforded. It is a fact that the apparatus frequently does not function upon the first press of the button, but that it can always be made to function by releasing and trying again. As in the case of the No.1 | ||