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).
Experiments with three modified 20 HP dynamos featuring two coils per slot.
| Identifier | WestWitteringFiles\L\July1924-September1924\ Scan62 | |
| Date | 25th August 1924 | |
| To R & E.{Mr Elliott - Chief Engineer} from EFC. c. CJ. & PN.{Mr Northey} c. BY.{R.W. Bailey - Chief Engineer} EP.{G. Eric Platford - Chief Quality Engineer} Wor.{Arthur Wormald - General Works Manager} c. Da.{Bernard Day - Chassis Design} Rg.{Mr Rowledge} EFC2/T25.8.24. X.4610. 20 HP. DYNAMO ARMATURE WITH TWO COILS PER SLOT. Three 20 HP. dynamos with this modification from standard, designated respectively B, E and 161, have been experimented upon. Dynamo 161. Preliminary bench tests of this machine, when first fitted with this special armature gave promising results, the commutation appearing to be excellent. The machine, with output set according to our production test, was then instructed to be fitted to 5-GII, which almost immediately went to R.{Sir Henry Royce} at W.W., subsequently to which it has been in the hands of Sales. Since that time we have not seem the chassis. On request for inspection and report on the condition of this machine, we have received the following report from Bk.{A. Birkett - Commercial Manager} :- "The appearance of the commutator is 100% "Brushes are in good condition and measure .813" "(original measurement would be .815" - EFC). "Maximum output is 8-3/4 amperes running on battery ignition. The machine generally is quite "satisfactory. Car has done 11,338 miles." (Speedometer reading when car left Derby 403 miles - EFC.) Dynamo B. With this machine attempts were made on the bench to prove that the noisiness was less than the standard armature, but nothing definite could be arrived at in this direction. In any case, it is known from other experiments that results on the bench in this direction do not carry any weight. Contd. | ||