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 changes for the revised 20 HP chassis, focusing on the rear springs and brake gear.
| Identifier | WestWitteringFiles\E\November1920\ Scan15 | |
| Date | 1st November 1920 | |
| To Da.{Bernard Day - Chassis Design} from E.{Mr Elliott - Chief Engineer} Copy to Gd. " " HS.{Lord Ernest Hives - Chair} " " EPC. " " EY. ORIGINAL. E3/G27/11/20. (4) X.4256 X.4262 RE REVISED 20 H.P. CHASSIS. We send you herewith blue print of drawing Lec.1313 which shews the chassis as far as it has been completed. You will observe the general arrangement of the brake gear in which it has been necessary to use the double lever reduction on the rear axle on account of the underslung springs. The rear road springs can be detached from the chassis by dropping them at the rear end of the axle until they clear the brake drums. They can then be slipped off their forward pins sideways. Mr. Royce wishes to use two leaf clips on each half of the spring with the object of tying all the shorter leaves to the longer ones for the purpose of resisting axle torque. He also wishes to make the spring stiffer pro rata in the centre to meet the increased bending moment load due to the axle torque. This torque we have taken at twice the low gear torque; this amount being fixed by Mr. Royce when considering the maximum that the springs are likely to carry. Mr. Royce would like you to work out the particulars of the rear road springs. The side channels on the frame can be ordered from Lec.1313. E.{Mr Elliott - Chief Engineer} DEC 1 C RECEIVED. | ||