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).
Letter from Adamant Engineering comparing the features and potential efficiency of Marles Gear versus Worm and Nut steering.
| Identifier | ExFiles\Box 28\3\ Scan035 | |
| Date | 1st November 1934 | |
| Messrs. Rolls-Royce Ltd. Contd 2. 1.11.34. We would like to point out, however, that there is one feature in the Marles Gear which is not present in an ordinary Worm and Nut type of Steering, such as that which we understand you fit as standard, and that is, that in the Marles Gear the gear ratio inside the box is constant throughout the movement of the rockershaft. In a Worm and Nut Steering this is not the case, the gear ratio being increased at the locks and lowest in the straight ahead position. The effect of this gives the Marles Gear a greater mechanical advantage than the Worm and Nut Steering at the lock position, which is where the heaviest work has to be done. No doubt you are well aware of this point, but we think perhaps it is a point relative to the matter we are discussing, i.e. ease of steering. As regards increasing the efficiency, we have not carried out any specific experiments on the exact size of gear we sent you, but we feel confident that this efficiency can be increased by fitting Needle Roller Bearings on the rockershaft journal instead of plain bushes. We are wondering whether you would like the writer to come up and see you on this matter generally, and if so, perhaps you will be good enough to fix an appointment. Assuring you of our best attention at all times, We are, Yours faithfully, for ADAMANT ENGINEERING COMPANY LIMITED. F.G.Matravers. Director. | ||