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).
Design specifications for a 20HP hypoid rear axle.
| Identifier | WestWitteringFiles\T\March1929-December1929\ Scan135 | |
| Date | 29th May 1929 | |
| FROM DA.{Bernard Day - Chassis Design} C. to HS.{Lord Ernest Hives - Chair} SECRET DA{Bernard Day - Chassis Design}1/M29.5.29. X2066 X 5350 20HP. HYPOID REAR AXLE. Herewith we send N. sch. 2886. shewing the hypoid rear axle casing for the 20HP. We have followed the lines of SS.{S. Smith} as closely as possible, and we have shewn that this axle is as strong, or stronger, in every respect than SS.{S. Smith} In order to make the gear teeth comparable we have disregarded the conventional diametral pitch, and fixed on a 10" dia. crown with 41 gear teeth, making the pitch to correspond. We understand that this is permissible. We do not wish to tie down the manufacturers of the hypoids in any way except as to number of teeth, and the approximate diametral pitch, but we have ascertained geometrically that these gears can exist. The New Departure type thrust bearing is made on the lines of the SS.{S. Smith}, that is to say, it is not a standard bearing, but all the dimensions are standard dimensions. The lubrication of this bearing we suggest should be made by coring a hole into the recess, which itself is sealed by the bearing housing. Should insufficient oil get through this hole we will provide a scoop, but it appears as though sufficient should get in. DA.{Bernard Day - Chassis Design} | ||