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).
Gearbox and sideshaft failure on a 25-EX left hand chassis.
| Identifier | ExFiles\Box 178\4\ img100 | |
| Date | 24th May 1932 | |
| ORIGINAL To R.{Sir Henry Royce} from Hs{Lord Ernest Hives - Chair}/Lid.{A. J. Lidsey} c. to Sg.{Arthur F. Sidgreaves - MD} Wor.{Arthur Wormald - General Works Manager} c. to E.{Mr Elliott - Chief Engineer} Da.{Bernard Day - Chassis Design} c. to By.{R.W. Bailey - Chief Engineer} Hs{Lord Ernest Hives - Chair}/Lid.{A. J. Lidsey}2/KT.24.5.32. x 310 P.II. GEARBOX - SIDESHAFT FAILURE. We have experienced a failure in the gearbox on 25-EX (left hand chassis). The sideshaft gears in use had a helix angle of 40° and it is possible that the consequent increased thrust was the cause of the failure. The attached photographs illustrate the nature of the breakage. The second motion shaft continuous gear was allowed to rock by the fracture of the gear and of its retaining piece. Both the gear and the retaining piece are very small in section where the fracture occurred and it may be advisable to stiffen these up, the radii at the point of fracture are very sharp. The rocking of the gear allowed it to foul the front ball bearing of the 1st motion shaft, damaging the gear teeth and breaking up the outer ball race. The flange of the gear retaining piece was fractured in several places as shown, and one of its bolts was broken. The 40° helix angle gears have been running in the car for a considerable time in conjunction with tests on sideshaft gear noise. Hs{Lord Ernest Hives - Chair}/Lid.{A. J. Lidsey} 2 - photographs attached. | ||