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).
Experimental work on Goshawk dynamos to reduce noise and improve commutation.
| Identifier | WestWitteringFiles\K\November1923\ Scan1 | |
| Date | 1st November 1923 | |
| To R.{Sir Henry Royce} & E.{Mr Elliott - Chief Engineer} from EFC. c. CJ. & PN.{Mr Northey} c. EY. EP.{G. Eric Platford - Chief Quality Engineer} DA.{Bernard Day - Chassis Design} c. WOR.{Arthur Wormald - General Works Manager} ORIGINAL EFC1/T1.11.23. X.4383 - GOSHAWK DYNAMOS. X.4333. We have a good deal of experimental work on Goshawk dynamos in progress, the experiments being with one of two objects in view :- (1) To reduce the noise of dynamos. (2) To improve the commutation. (As regards output and temperature rise, in cases where the commutation is satisfactory, this feature is O.K.). The more recent features, as regards the present brush gear, which we have, to improve the commutation are :- (a) The bevelling of brush tops to receive the spring pressure in an inclined direction causing every brush to run in plane contact with one side of the brush holder. (b) Improved method of undercutting by which no stray mica remains flush. (c) Brushes in other materials. (d) Heavier brush spring pressure. (e) Armature with two coils per slot and one dummy, using commutator of 57 segments. The experiments which we have on hand to reduce noise are :- (e) Armature with two coils per slot and one dummy, using commutator with 57 segments. (f) Armature with straight slots. (g) Trailing edges of field poles eased off. (h) Cast iron end bracket. Contd. | ||