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).
Letter to Mr. Bentley discussing design modifications for small 2-pole motors and DC/AC brush holders.
| Identifier | Morton\M6\ img008 | |
| Date | 24th November 1929 | |
| (1) West WitteringHenry Royce's home town Nov 24/29 Sunday Dear Mr Bentley Re small 2 poles for 400v. The difficulty was thought to be due to the unreliability of thin sections of thick castings so that a wrought tubular yoke. If this is not so there is no need of a short, thick ring. My object of making the ring short & thick was to enable the feet to be cast on the outside. I intended to drill into the thick yoke not long studs, unless these are thought less expensive or bolts. Re. D.C. brush holders. I rather thought you had given up bushes and washer insulation for brush holder, because of the low voltage & the presence of copper & carbon dust. Re. AC brush holder I think your square spindle is not big enough to get hold of firmly & be rigid, it is much more rigid if one works my way, by forcing into a drop forging. PTO | ||