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).
The mechanical efficiency of a Marles Type L.7. R.H. Steering Box.
| Identifier | ExFiles\Box 28\3\ Scan023 | |
| Date | 11th October 1934 | |
| X4094 11.10.34: Mechanical Efficiency of Marles Type L.7. R.H. Steering Box. The figures given below were taken on the steering box as received from the makers, i.e., before it had been run in. It was noticed that the roller which engages with the worm threads was rather stiff in its bearings and did not roll on the threads with pendulum lever loads below 50 lbs. Therefore the figures obtained for the load on pendulum lever to rotate wheel with the wheel free are likely to vary as the gear becomes "run in". All loads and efficiencies were measured at the mid position. Overall turns of steering wheel = 2¾ + 10°. Overall movement of pendulum shaft = 68°. Overall ratio of box (i.e. lock to lock) = 14.75. Mid. position ratio = 15.0 Pendulum lever length = 10.15. With steering wheel free load required at end of pendulum lever to start rotation of wheel = (1) With Mobiloil D in box 8.81 lbs. = (2) With Mobiliol EP{G. Eric Platford - Chief Quality Engineer} in box 8.06 lbs. | ||