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).
Design and analysis methods for 'Goshawk II+' road springs.
| Identifier | ExFiles\Box 49\3\ Scan035 | |
| Date | 1st March 1921 | |
| X.426$1 To R.{Sir Henry Royce} from Da.{Bernard Day - Chassis Design} c. to BN.{W.O. Bentley / Mr Barrington} c. to E.O. De4/CBS.3.21. X.4261 X.426$1 ROAD SPRINGS - "GOSHAWK II"+ We have made two schemes N.sch.788 rear springs and 790 - front springs, both of the heaviest weight, namely, 1100 and 660 lbs. respectively, based on a car of 35 cwts. The method by which these springs have been designed has been shewn on N.sch.771 and N.sch.789 and again both have been analysed by the method shewn on N.sch.779. We wish to point out that though the building up of the spring is not so very difficult a job, there is a considerable amount of trial or error involved. While in the case of the analysis of the spring, there is a very great deal of arithmetical work called for. Particularly so if an exact account is taken of the ends of the leaves by the method shewn on N.sch787. Because of this latter we have found that it is a great convenience to assume that the ends are square and that this approximation is very nearly true in the case of leaves shaped as we propose they should be shaped, namely, to the nearest approximation to the parabolic shape which gives constant stress. That can be obtained by a simple grinding process. We should like to remark that we know that the methods of building up the spring are not strictly accurate, but we think that the method of analysis is accurate and Contd. | ||