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).
Analysis comparing Hypoid and spiral bevel gear ratios, stresses, and loads for an axle assembly.
| Identifier | ExFiles\Box 123\3\ scan0013 | |
| Date | 14th July 1933 | |
| - 2 - casing we can get in a considerably higher ratio in Hypoids viz. 13/37 = 2.845, in which though the crown wheel is 9", the load per in. is not high. Ratio. MPH at 3150. Crown wheel dia. D.P. Stress lbs Load per in. of face /lbs 13/37 =2.845. 98.9. 9.1875. 4.03.97600 7640. This seems to be about the best we can do in hypoids. We have shown the proposal on N. Sch.3755 herewith. For the Continental sports type of body it is understood that a spiral bevel gear would be suitable, the seats being always forward. We can get a spiral bevel of 11/31 = 2.82 ratio of which the particulars are as follows: Ratio. MPH at 3150. Crown wheel dia. D.P. Stress lbs. Load per in. of face./lbs. 11/31 99.6 10 3.1 98500 7440 10/31 This has been shown on N. Sch.3764, herewith, and as the load and stress is reasonable, with a big D.P. it is suggested that this should be the one made now. A new centre casing, new side plates, bridge piece, and differential casing, are needed, but the bulk of the axle pieces are as J.3. Da.{Bernard Day - Chassis Design} | ||