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).
Investigation into gear knocks on the Goshawk 11 engine, proposing experiments with gear slack.
| Identifier | WestWitteringFiles\K\June1923\ Scan23 | |
| Date | 25th June 1923 | |
| TO HS.{Lord Ernest Hives - Chair} FROM R.{Sir Henry Royce} c. to RG.{Mr Rowledge} c. to CJ. ORIGINAL GOSHAWK 11. - HALF TIME GEARS. X6569 It has not been clearly demonstrated to my mind whether gear knocks are due to the camshaft alone or to a combination of the speed variations of both the crankshaft and the camshaft. Generally our troubles are due not to one cause alone but to a combination of 2 or more causes. I would therefore like you to try the following experiments with slack and no slack in the wheel teeth:- [Table] EXPERIMENT. | TEST. | REPORT. NO SLACK ANYWHERE. | Try a set of gears carefully fitted up without slack anywhere. This should not suffer from knocks. | No Knocks SLACK. NOSLACK. | Try now introducing slack into the pump drive. This might be permissible owing to the pump drive having sufficiency of steady load to follow a speed variation and not much inertia. | No Knock SLACK. NOSLACK. | Try now introducing slack in the dynamo pinion. If as I think there is a crankshaft speed variation this should be subject to gear knocks. | We want to know if it is possible to have slack in all the other gears if the crankshaft and camshaft are coupled together without slack. [Signature] R.{Sir Henry Royce} | ||