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 decisions and proposed modifications for front flywheels, magneto, and air pump.
| Identifier | ExFiles\Box 181\M11\ img105 | |
| Date | 18th December 1918 | |
| To BY.DA.{Bernard Day - Chassis Design}& EH. from R.{Sir Henry Royce} -6- R7/G181218 Contd. (7) FRONT FLYWHEELS. The absence of balance weights, the lighter crank-shaft, lighter connecting rods, and lighter pistons, all help towards the reduction in size of the front flywheels. It is understood from Mr. Hives that these have been reduced successfully to about 11" diameter. Mr. Royce would like Mr. Bailey to make a new design of this part for the engine, shewing the existing friction damper rings, existing springs, washers, and studs, but the smaller flywheels to dimensions supplied by Mr. Hives, and a smaller flywheel casing to suit. (8) MAGNETO. Mr. Royce wishes to avoid the use of long cams on the low tension mechanism of the magneto. Since it is very possible that Watford magnetos will be adopted for the chassis engine, this point will be met since the Watford cam is of the short flat type. (9) AIR PUMP. It does not seem possible or desirable at the present time to depart from the pressure feed system on the car. Some improvements might be made to the air pump which is located on the governor casing by - (a) Applying experimentally aero relief valve as the delivery valve of the pump. This valve under test was considered to be noisy, but with limited lift and the limited delivery of the chassis engine pump, it may be quite satisfactory. (b) Raising the limit of pressure of the pump to three pounds per square inch, so as to increase its pumping rate. (c) Increasing the diameter of the bore of the pump 40% for the purpose of doubling the pumping rate. Will Mr. Bailey get these moving. (Contd.) | ||