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).
Failures of 20/25 HP chassis dynamos and proposed improvements.
| Identifier | ExFiles\Box 168a\3\ img173 | |
| Date | 22th March 1935 | |
| To [redacted] and Wors from E.{Mr Elliott - Chief Engineer} c. Hs.{Lord Ernest Hives - Chair} Hy{Tom Haldenby - Plant Engineer}/Wst By/RD. E.6/HP.22.3.35. re 20/25 HP. Chassis Dynamos. The following memo is to record discussion between Hs{Lord Ernest Hives - Chair}/Wst. By/RD. and E.{Mr Elliott - Chief Engineer} on the 20/25 dynamo position. The troubles being considered are:- (1) The failure of the dynamo on 21-C-IV during 10,000 miles test in France. (2) A certain number of failures of the voltage controlled 20/25's in customers hands due to vibrator contact sticking. Referring to No.1. it is agreed that the dynamo was running an overload test with 60 watt. head lamps in place of the 48 watt. we officially recommend, and 6 watt. side and tail in place of the 4 watt. we recommend, and that there was a large percentage of night time running at very high speeds. It is known also that there was considerable sparking at high speed and that this, combined with the overheating of the armature would result in the solder being melted. It is agreed that there should be little likelihood of a breakdown on a customer's car because although he may have a wireless set fitted it would mean running at night time at high speed with the head lamps on and with the wireless set in operation to produce the worst overload results. Nevertheless it is felt that improvements we already know of should be brought in as soon as possible. These improvements are as follows:- (a) Ventilated dynamo. | ||