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).
Technical notes and specifications for the Goshawk dynamo, including details on armatures, current-density, brush-gear and brush spans.
| Identifier | ExFiles\Box 50\5\ Scan314 | |
| Date | 5th June 1924 | |
| X 4-383 5.6.24. GOSHAWK DYNAMO NOTES. X4383 X4633 ----- Expl. Std. and thick carcase armatures. Resis. std. .347 ohm "Th.C" .365 ohm. Diff. .018 ohm Ratio 1.05. Armature active length, standard 2.8" (helically). Th.C. 2.75". ----- Gos. dynamo brush current-density. Area = .75" x .3" = .225 sq.". Main current (+) = about 16A ". Density about 70A/sq." ----- Gos. dynamo pressed brush-gear, clearance from comm. by drawing - .075" Ditto Scintilla on actual machine (2057) approx. .125". ----- First Gos. dynamo with retarded comm. No.383. Goshawk brush spans. On one coil per slot machine .3"(main)= 1.32 segments. " two " " " " .2"(control)= .88 " " " " " " " .3"(main) = 2.59 " " " " " " " .2"(control &) 1.73 " (mod'fd. {Frank Dodd - Bodies} main) " " " " " " .125"(modif'd) 1.08 " (controb) Goshawk pole-shoe displacement. .25" of pole-shoe, equiv. to .374" on carcase (for brush adjustment). Goshawk 2 coil/slot brush position is 3.5° less retarded than std. 29 segment arm: = 3.5° more than old 29 segment. Correct std. brush (main) position on Gos. dynamo. Contd. | ||