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).
Advantages and implementation of larger pitch bevel gears for the 20HP chassis axle.
| Identifier | ExFiles\Box 49\2\ Scan161 | |
| Date | 1st May 1923 | |
| R.R. 199 (250T) (S.D.676 19-7-17) MP 180865 X4256 BJ. c. WOT. c. Hs.{Lord Ernest Hives - Chair} BY1-P1.5.23. 20HP CHASSIS. RE LARGER PITCH BEVEL GEARS FOR AXLE. Referring to BJ2/H28423 and further to my previous correspondence on this subject, we think that the conclusions arrived at in this memo are, in view of the facts, too severe. (1) All the Technical people at Derby are satisfied that since the pitch increases the strength, the wearing surface and the oil film, the gear cannot possibly be less trustworthy than the present one. This conclusion is also confirmed by R.{Sir Henry Royce} independently in his memo R7/M26423, of which you have a copy. (2) The 10,000 miles trial is actually in hand already and is being pushed through with the object of saving all possible time in this connection. He is quite certain that he will get the test through before any cars to which large pitch axle bevels are fitted reach customers hands. (3) The design of the gear as a whole is unaltered, the only two points which have been modified being that the Rim is strengthened and the tooth is strengthened - the result is that we have obtained quiet gears with much less effort, the gears themselves being actually better than any gears we have produced with the standard smaller type tooth. (4) We must point out that the small pitch teeth which are at present standard are failing on the dynamometer for two reasons;- a/- The tooth itself is being cut into. b/- The gears themselves are developing noisy. so that even from this point of view the present gear cannot be considered satisfactory. The unanimous conclusion of the technical people at Derby is, that we should at least provisionally pass the gears and go ahead producing this type of gear without delay, as it makes it considerably easier to produce larger numbers of quiet bevel gears whilst maintaining the full standard of quietness. ...contd | ||