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).
Secret document detailing modifications and required corrections for the SS. press button starter switch.
| Identifier | WestWitteringFiles\T\March1929-December1929\ Scan131 | |
| Date | 25th May 1929 | |
| DY.{F R Danby} FROM E.{Mr Elliott - Chief Engineer} C. to <s>BG.</s> EPC. HS.{Lord Ernest Hives - Chair} g SECRET. SS.{S. Smith} PRESS BUTTON STARTER SWITCH MODIFICATIONS. We send herewith LeC. 2710. dealing with the above. R.{Sir Henry Royce} remarks - "This press button switch is alright if it is corrected. We must expect it to be corrected once. All the constituent parts are simple. There should be no fitting. The work consists of either mouldings or pressings. We will send the corrected dimensions for the spring. I do not like the spring washers used under the screws: they seem somewhat miserable. The section of the washer should be wider." The modifications shewn on LeC. 2710. are as follows:- (1) Longer, thinner, bow spring with modified anchorage permitting of more flexibility. (2) Slightly thicker base to switch to provide more clearance between front and rear features. (3) Coiled springs of flat section for holding up the fixed carbons. (4) Hexagon ends on inserts for fixing screws. The following points on the model switch sent to WW., do not follow the original design LeC. 2641: and require correction:- (a) The model shews depressions in tops of moving carbons for spring ends. These are not desired as they pull the carbon out of square when the switch is depressed. (b) The moving carbon springs are located in their correct position by tails engaging notches cut in the switch armature. These tails have not been made as long as specified, and the notches are unnecessarily deep. (c) The model is not furnished with a stop plate for the copper brushes as shewn on LeC. 2641. The brushes should be more flexible and set up against the stop plate. E.{Mr Elliott - Chief Engineer} | ||