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 a 'B failure' related to spring tension, gear engagement, and resulting operational issues.
| Identifier | ExFiles\Box 64\4\ scan0093 | |
| Date | 17th October 1928 guessed | |
| -2- Contd. The B failure appeared to occur only with the stronger spring because with the weaker spring the excess of longitudinal traction over spring pressure was sufficient to overcome the slight friction and to pull the armature right into gear. To overcome this fault with the stronger spring it has been necessary to ease the teeth slightly. The stronger spring which has been included in the present arrangement is somewhat better in other respects, one of which has already been referred to. Another respect in which the stronger spring is better is that the end thump on engagement is, as previously reported, considerably reduced. The end thump on disengagement has been experimentally almost eliminated by putting in a rubber washer. It is not suggested that these modifications are necessarily those that are required for the final arrangement, the intention is only to inform you of the results of observation in various circumstances. The present phenomena in the operation which are of an undesirable nature are :- (1) Some thump on engagement. (2) Some gear noise when motor is driving engine which has of necessity been slightly increased by easing the teeth manually. (3) A short and sharp gear scream on disengagement. (4) A possibility of failure on the first press though no possibility apparently of complete failure. The above results do not apparently affect the desirability of the armature taper modification to which we refer in our previous report. EFC. | ||