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).
Dynamo specifications, suppliers, and design modifications, including diagrams.
| Identifier | ExFiles\Box 4\5\ 05-page173 | |
| Date | 1st March 1921 | |
| Contd. -2- El/GS1.3.21. (e) Can we afford to use the Bleriot cutout? What is the difference in cost? It is very rarely that the differences in cost are sent to Mr. Royce for his consideration. (f) We have gone off Smiths because they cannot quieten their machines or give us a regular and sufficient supply of machines. We might consider what the Rotax Company could do for us. (g) Modify all the experimental dynamos being dealt with into third brush machines if possible. (h) We want the following models of dynamos for our large and small cars :- At ordinary working temperatures. { 6" carcase 12 volts 10 amperes cut-in 500 full output 750 for 40/50 H.P. (12 amps max) (10 miles) (15 miles per (8 amps min) (per hour) (hour). { 5 1/4" carcase 12 volts 7 amperes cut-in 600 for 15 a 20 H.P. (8 1/2 amps max) (5 1/2 amps min) It is permissible for the dynamo to have a falling characteristic, provided its first rise is sharp enough. What can we buy to fit these specifications? (i) The 40/50 H.P. dynamo made from starter motor parts should be finished as 3rd. brush machine, as Mr. Royce thinks we may learn something from it. (j) If we fix our standards as 6" and 5 1/4" for our two dynamos, we can easily put in other makers' smaller machine for test. (k) Mr. Clark to find out what are the proportions of other people's armature and carcase diameters. The R.R. table of dynamos and motors is as follows :- OUTSIDE DIA OF ARMATURE CARCASE [Diagram 1 dimensions: inner 3.5, outer 6] [Diagram 2 dimensions: inner 3, outer 5.25] [Diagram 3 dimensions: inner 2.75, outer 4.75] Contd. | ||