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).
Damper and oil performance tests, comparing different oils and analysing road comfort.
| Identifier | WestWitteringFiles\O\2April1926-June1926\ Scan154 | |
| Date | 26th May 1926 | |
| Exhd. Report (Contd) -3- Hs{Lord Ernest Hives - Chair}/RmL/T26.5.26. damper compared with "Price's Motoring C". The former does not cease to flow until -15°C. The latter at -6°C, approx. We do not think that with "Lovejoy" oil and our present size passages we should ever get harsh riding in cold weather such as is associated with "Houdailles", and obviously should not get the ineffectiveness in hot weather inherent in this type due to our fixed loading by valves. The main trouble occasioned by thin oil is the increase in oil leaks. We are making somewhat comprehensive tests with various oils and flows to obtain all the information possible about fluid damping. The "Lancia" people seem to employ quite a normal type of oil with success. We have approached Price's and Wakefield's with a view to getting what we require. We attach a chronograph record of the worst portion of our test stretch of road used for low speed riding comfort tests. Two contacts were arranged between the axle and frame, one of which actuated a pen when the distance between the axle and frame decreased by .500", the other when the distance decreased by .750". It appears that about 75% of the bumps are less than .750". The spring seems to be absolutely following the contour of the road as the frequency of the contacts reaches 7/sec. and is always much higher than the natural spring period. The viscous damping with the present shock dampers and an oil having a time of efflux of about 500 secs. would appear to be about 30 lbs. | ||