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).
Tests conducted on a 'USA' 4-speed gearbox, focusing on modifications to the reverse gear.
Identifier | ExFiles\Box 6\4\ 04-page038 | |
Date | 29th January 1925 | |
EXPERIMENTAL REPORT Exptl. No. REF: HS{Lord Ernest Hives - Chair}4/LG29.1.25. S E C R E T. 'USA' 4-SPEED GEARBOX. To R.{Sir Henry Royce} From Hs.{Lord Ernest Hives - Chair} c. to CJ. BJ. c. to RG.{Mr Rowledge} E.{Mr Elliott - Chief Engineer} c. to DM.{D. Munro} AJS. c. to SY. Wor.{Arthur Wormald - General Works Manager} We carried out a test using the original reverse shaft and gears, the only modification being that the forks were relieved. With this arrangement the reverse worked out immediately. If the gear was held in, the fork being relieved, allowed it to work out further, and actually the selector mechanism was sprung so that the load came on the edge of the teeth and stripped them. We have carried out a further test by taking a standard reverse shaft and reducing the diameter so that it was .900" throughout the whole length instead of having a step up of 1.050". This was tested and it was found that there was no tendency for the reverse to work out. The car was run for half an hour full power maximum torque on reverse. The parts when dismantled were in excellent condition. The results of our tests so far shew that relieving the forks has not caused the improvement - that the stiffer shaft has not caused the improvement. It is when we have had a parallel shaft that we have had no trouble. Hs.{Lord Ernest Hives - Chair} | ||