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).
Modifications and troubleshooting for the J. 3. Engine Unit, focusing on half time gear issues.
| Identifier | ExFiles\Box 178\3\ img107 | |
| Date | 15th March 1932 | |
| ORIGINAL. R1/M12.3.32. Sent from WW. 15.3.32. X5770 E.{Mr Elliott - Chief Engineer} BY.{R.W. Bailey - Chief Engineer}) FROM R.{Sir Henry Royce} HS.{Lord Ernest Hives - Chair} (At Le CanadelHenry Royce's French residence.) C. to Sir. WDH. FG. [text crossed out] J.{Mr Johnson W.M.} 3. ENGINE UNIT. (REFERS ALSO TO J.{Mr Johnson W.M.} 1.) Any modifications that are thought necessary to this unit should be work for Mr. Elliott at Derby, where he should have from four to six assistants working on car engine design, which he will send to me from time to time as he thinks profitable. [text crossed out] You started well, though you are now into many troubles, but do not lose heart; we ought by our experience to expect it. Anyway we have J.{Mr Johnson W.M.} 1. to go on with. (1) HALF TIME GEARS. I am sorry these are troublesome, more than I am sorry that we cannot potter with them by repeated changing etc on the engine. It is of primary importance that we have a test rig where we can prove (marry) or do all that is necessary before putting them into the engine. Perhaps a second test can be made after the pinion is on the crankshaft - i.e. a skeleton crankchamber. (2) They can be thoroughly proved before the pistons etc are fitted. One believes it may be a microscopic difference in the spiral angle, and possibly it is less critical the greater it is. Try up to 45°. (3) The first thing occurring to me is that the camshaft wheel is too flexible sideways, and may slide along the teeth, or it may vibrate. Make this wheel very stiff and well damped. Perhaps it could be damped with a side plate of aluminium, with damping material between, such as bakelite sheet paper. (4) Perhaps the overhanging camshaft does not support its wheel stiffly enough, so that even a stiff wheel may vibrate by bending the shaft. Try a bearing on the other side of the wheel. There is a cover there which can be made into a blind bearing. (I am only going by memory about this, and the carburetter, and where you have trouble and expect me to give help, send drawing of the piece complained of.) (5) Naturally this may be an easy way out, if there is any material that we could trust. The nearest I know is bakelite, and it might be tried as an experiment, but not adopted unless we are forced to. (1) [Side Annotations] TEST RIG. TRY INCREASED SPIRAL ANGLE. CAM WHEEL GREATER SIDE STIFFNESS. SUPPORT OF CAM WHEEL. NON-METALLIC CAMWHEEL. | ||