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).
Technical memo discussing manufacturing difficulties and design alternatives for rear springs, specifically plate thickness and eye types.
| Identifier | ExFiles\Box 49\3\ Scan099 | |
| Date | 10th May 1922 | |
| To BY. {R.W. Bailey - Chief Engineer} from Da. {Bernard Day - Chassis Design} c. to CJ. c. to Wor. {Arthur Wormald - General Works Manager} c. to Hs. {Lord Ernest Hives - Chair} X.4261. Da {Bernard Day - Chassis Design} 2/M10.5.22. FRONT (crossed out) RE REAR SPRINGS. X.4261. Y2628 Thank you for your telegram of yesterday. We are sorry to hear that you experience difficulty in getting top plates with solid eyes of less than 1/2" thick. We wonder what the extent of the difficulty is. Itis possible that a 1/2" plate could be obtained and this ground to the required thickness as an experiment? If the results were found to be very good it might then be worth while taking some additional steps to get these plates by a cheaper means. If we find that it is impossible to go below 1/2", then the only alternative is to limit the deflection of the spring by increasing the rating and thickening the buffers. We are going to send you instructions for this in the course of a day or two, and as Mr. Royce has often mentioned thickening the buffers, it may be that this will prove the best way out of the difficulty. With reference to the rolled central eyes, while they are not so good as solid eyes we should think they were better than rolled off-set eyes. There is a place on one side of the eye where there is a bending moment due to the radius rod tension but at this point there is no tension due to the deflection of the spring. In the case of the rolled eye on one side tension due to radius rod action and due to bending occur at approx: the same place and so the stress is certainly more. We think, however, that we should only fall back on rolled central eyes as a last resort. (DA {Bernard Day - Chassis Design} ). | ||