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 items for the electrical system of the 19-EX, including a voltage-regulated dynamo, universal battery, and starter motor.
| Identifier | ExFiles\Box 178\4\ img032 | |
| Date | 20th April 1932 | |
| To R.{Sir Henry Royce} from Hs{Lord Ernest Hives - Chair}/Wst. c. SG.{Arthur F. Sidgreaves - MD} c. WOR.{Arthur Wormald - General Works Manager} E.{Mr Elliott - Chief Engineer} c. Ev.{Ivan Evernden - coachwork} R.{Sir Henry Royce} Hs{Lord Ernest Hives - Chair}/Wst.6/AD20.4.32. EXPERIMENTAL ITEMS ON ELECTRICAL SYSTEM OF 19-EX. Voltage Regulated Dynamo. We have converted one of our standard 40/50 dynamos to a plain shunt machine by rewinding the field coils with 21 S.W.G. wire and replacing the taper poles with concentrically ground poles. The third brush has been removed and the field connected straight across the armature main brushes. In conjunction with this dynamo we are running a standard C.A.V-Bosch B.2 regulator which has been adjusted suitably to run with our dynamo. This regulator is similar to the Bosch regulator on the Alpha dynamo and consists of a voltage shunt wound coil and current compensating series coil operating two sets of contacts. One pair of contacts open first, as the voltage rises, and inserts a resistance in series with the field and as the voltage rises still further the second pair of contacts close and short circuit the field. This is the same operation in principle as the Bosch. The idea of this test is to gain experience of the consistency of a voltage regulated system in maintaining the battery at the correct state of charge. Universal type battery. One of these batteries prepared by the National Accumulator Co. (P & R) in a moulded Dagenite case has been fitted. This battery has the same long life features incorporated as in our standard battery. The moulded container, however, is of the correct dimension which allows the battery to be serviced at any time in emergency with a standard 6-volt battery unit stocked universally in every country by battery service agents. Starter Motor. We have fitted experimentally a standard motor arranged with bearings which are self lubricating. A spring loaded felt pad is let into the bearing bush and this felt pad is fed with lubricant from a reservoir of oil soaked cotton packed in a circular recess round the bearing. This idea is similar to the bearing lubricating feature on all Bosch motors. | ||