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).
Response to a query addressing issues with battery discharge, dynamo operation, and drive belt adjustments.
| Identifier | ExFiles\Box 36\4\ scan 131 | |
| Date | 24th September 1920 | |
| X3014b ROLLS Royce of America Inc. Springfield, Mass. By3/P24.9.20. X.3014b X.3770 X.376 X.3735 Referring to Qy5/G3.9.20, the actual facts X4211 of the case are as follows:- (1) It is quite agreed that if cars are used persistently at night on town service so that the lighting and starting units are used regularly, they will in the end run down the battery. The remedy suggested for this by Mr. Royce was, that a charging current should be used during the day taken from the town main. As a matter of fact full instructions to cover this particular weakness are being included in the Instruction Book. In order to make the matter quite clear I am sending herewith an extract from the book in question covering this point. The Instruction Book has not been published, but copies of same will be sent to America as soon as they are available. In regard to paragraph (3) we feel quite sure that this statement is a mistake - as a matter of fact when the outfit is hot the actual current taken is so small that there is not the slightest chance of a belt slipping at cut in speed, as a moments reflection will make it plain that just at the point of cutting in there is approximately no resistance of the turning of the dynamo, and therefore there cannot be slip. Otherwise the dynamo would not drive at all at high speeds. The real reason for the later cut-in is that the cut-in itself, in conjunction with the dynamo, when hot, actually cuts in and prevents the dynamo cuttin in until a slightly higher speed is reached. From experiments carefully carried out the cuttin in speed in miles per hour with the whole outfit hot is 16 miles per hour with the whole outfit hot is 16 miles per hour. In regard to paragraph (4) it is not considered desirable to include ridges on the driving faces of the vee pulleys. The remedy for paragraph (5) is to notify all owners that there is no need to tighten up the belt in the manner indicated in the letter, so that it twangs like a bow string, but to explain the points raised above, when we feel confident that the complaints will disappear. Contd. | ||