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).
Analysis of a C.A.V.-Bosch shunt wound dynamo and regulator.
| Identifier | ExFiles\Box 178\4\ img055 | |
| Date | 1st April 1932 | |
| To E.{Mr Elliott - Chief Engineer} from Hm{Capt. W. Hallam - Head Repairs}/Pgt. c.c. Fg. W.R. c.c. Fa. c.c. Sa. W.L. Hs{Lord Ernest Hives - Chair}/Sgt.1/ADST.4.32. X4562 X6092 C.A.V.-BOSCH SHUNT WOUND DYNAMO AND REGULATOR. We recently obtained a C.A.V.-Bosch shunt wound dynamo fitted with a regulator. This was obtained, partly on account of our investigations into dynamo output regulators and partly as the result of a suggestion that the complete dynamo and regulator may possibly prove a suitable unit for the Pensport. This machine, although presumably representing the combined technical knowledge of the two manufacturers, and made in this country, is based mainly on Bosch design. It is suitable in size for the 20/25 car having the same carcase diameter as the smaller of our dynamos. The regulator, like the Bosch, is mounted on the dynamo. It is not, however, combined with the cutout, the latter being a separate unit mounted elsewhere on the chassis. DYNAMO. The dynamo itself very closely resembles the Bosch. No rated output is stated on the machine but from our bench tests we should say that it is 175 watts at 13.0 volts. The brush gear is similar to that on our 20/25 dynamo in that single brushes are used in pressed sheet metal holders. Pressure on the brushes, however, is applied in a different manner, a pressed sheet metal finger which is controlled by a wire spring, being used. Like our own machine it is insulated on both poles. REGULATOR. This unit appears to be the same as that made by Bosch previous to the cheapened type recently introduced and in which the armature is in the form of a bell-crank lever. It is of the vibrating contact type with the whole of the contacts and mechanism enclosed and sealed in a cylindrical casing. From this it is clear that the contacts are not intended to be cleaned or adjusted. In operation it is the same as the Bosch i.e. resistance is inserted in the first stage and the field winding short circuited in the second. It is neat and strong in appearance and the operating voltages are not so affected by temperature as in the case of the Bosch. On the other hand, smoothness of operation is affected by temperature, being more unsteady when hot. | ||