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 modifications for Michelin wheel axles, hub nuts, locking mechanisms, and brake components.
| Identifier | WestWitteringFiles\F\March1921\ Scan15 | |
| Date | 8th March 1921 | |
| TO DA.{Bernard Day - Chassis Design} from E.{Mr Elliott - Chief Engineer} -2- E2/C8/3/21 Contd. it will be discharged through the over-flow passage in the cast aluminium brake cover. (8) The Michelin wheel axle Mr. Royce thinks is more urgent than the one for the wire wheels, since we have not got the wire wheels and are not likely to get them for some time. Mr. Royce would therefore like the hubs for the Michelin wheels prepared first. (9) The hub nut for the inner ball bearing should be locked by a plate secured with a single bolt, and a differential adjustment should be obtained by drilling extra holes through the brake drum and hub flange between the securing bolts. The number of castell-lations on the nut must, of course, if necessary, be altered to produce a differential effect. The locking plate may be prevented from rotating by forming it with two horns at a suitable distance apart, which reach down into the undercut behind the thread. (10) It appears difficult, Mr. Royce considers, to operate the sheet metal lock washer shewn for securing the axle tube nut. He would therefore like this nut to be locked by means of a set screw passing through it into the washer behind, the washer being in turn locked to the axle tube by castellations, as in sketch- * GROOVES THRU THREAD ON AXLE TUBE Two such screws should be used placed on a diameter, and a differential adjustment should be provided by having a number of tapped holes in the nut, and a number of plain holes in the washer, each number being a multiple of two for the convenience of the two screws. (11) The pin for securing the brake pull-off springs to the brake shoes should be made with a smaller head, and a larger pin. It is only necessary to have a small head to prevent the pin going too far, whereas the pin should be large enough to be conveniently gripped by a pair of pliers. This alteration should be made retrospective to "Goshawk I" if the same pin is being used. (12) The inner ball bearing outer race should not be gripped by the hub nut. The hub should stand proud of the outer race, and a wide fibre washer about .032" thick should be introduced before screwing on the nut which is believed to be our standard practice for the 40/50. E.{Mr Elliott - Chief Engineer} | ||