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 memorandum discussing issues with fitting Marles Weller steering components and proposing alternative damping solutions.
Identifier | ExFiles\Box 28\2\ Scan194 | |
Date | 24th May 1933 | |
K2094 To Sg.{Arthur F. Sidgreaves - MD} from E.{Mr Elliott - Chief Engineer} c. Wcr. Hs.{Lord Ernest Hives - Chair} By.{R.W. Bailey - Chief Engineer} Ba. RR. type Marles Weller Steering. Referring to Hs.{Lord Ernest Hives - Chair}5/MJ.23.5.33, we should like to point out that we were only able to make a thread and nut with Marles Weller pads to fit in an existing RR. steering box. To make the best of this scheme it would have been necessary to alter the whole box to increase the lead angle, and also to lower the steering ratio. This nut, having been tested on the rig, shows a lower efficiency than we think can be used in the existing box. As the nut has been put up with line contacts instead of the pads being hollow ground, as specified, the bearing of the pads is very attenuated and in consequence the efficiency is less than it should be. The Marles Weller steering box itself is somewhat unmechanical. All the pads taken from the steering on 58-GN were cracked right through rather indicating high loading from shocks. We feel that the steering box is too late in the system for the application of damping and that there should be an adequate damper on the axle itself. This would go a long way to subdue the axle without noticeably interfering with self centreing and reversibility. The present damping surfaces we have on the RR.cross steering ball pads are hardly suitable for this duty and do not stay put on cars habitually driven at high speed. We suggest that a well damped axle and efficient steering is to be preferred to using a less efficient box and is safer for use with a side steering tube provided with more definite control for improved selectivity. The tendency we have towards a self damping steering box and no springs in the side steering tube appears to be open to serious objection in respect to the stresses thrown on the steering mechanism. | ||