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).
Motor experiments concerning spring rates, dampers, and engaging/disengaging thump.
| Identifier | ExFiles\Box 64\4\ scan0152 | |
| Date | 22th December 1928 | |
| EFC/T22.12.28. -2- Contd. If, therefore, we apply the main current earlier it would appear that we could use a rather lower rated spring and still have little engaging end thump, but at the same time have less disengaging end thump. This is not a modification that can be done by adjusting the contact gap, because that gives too limited a range. In regard to the air damper with which we experimented this, as previously stated, was partially effective in the short motor on chassis 9-EX, because on that motor we were able to get a longer damper stroke. On the lengthened motor we did not get the same length of effective damper stroke and that, together with the fact of the increased mass of the armature, also the fact that we have to be quite clear of any solid frictional effect, rendered almost ineffective a similar arrangement tried on one of these longer motors. For the time being we are concentrating on making all other features, as referred to, as O.K. as possible, i.e. except end thump on disengagement. EFC. | ||