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).
Concluding page of a letter discussing a solution to a valve gear problem by using spring loading.
| Identifier | ExFiles\Box 147\1\ scan0037 | |
| Date | 2nd April 1935 guessed | |
| - 3 - so far as it provides a cushioning effect between impacting parts. As an instance I mention the Armstrong Siddeley "Special" where the oil pressure, except as a lubricant, is clearly intended only to take up the slack in the valve gear due to tappet clearance for in this model the rocker arms are provided with the usual tappet adjusting screws. In my opinion the same effect could be arrived at more simply and at less initial cost in that unit by adopting the system of spring loading which I advocate and eliminating the complicated oil passages and ball valves. In conclusion I suggest that commercially and practically speaking this particular problem can only be dealt with by some form of spring loading and by grouping the additional springs about the valve stem itself as I have shown them so that they do not diminish the strength of the valve spring when closing the valve, a criticism which I think can be levelled at designs hitherto put forward. I had hoped to be able to send you a sample before now and hope to do so shortly. Yours faithfully, (Signed) A.{Mr Adams} B. BUCKLEY. | ||