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).
Investigation into change gear lever vibration and audible noise on the 20 HP model.
| Identifier | ExFiles\Box 6\4\ 04-page182 | |
| Date | 3rd December 1927 | |
| Hs{Lord Ernest Hives - Chair}/GWH{George W. Hancock - Head Chateauroux}/LG3.12.27. 20 HP. CHANGE GEAR LEVER. There have been complaints of the change gear lever vibrating and causing an audible noise when running in 3rd. gear at speeds of 38 to 42 m.p.h. Our investigations have proved that the noise comes from the plunger, this being caused by the compression rod G.51852 vibrating lengthways at a high speed which is transmitted to the plunger. We found after a series of tests that the only way to prevent the compression rod conveying the vibrations to the plunger was to fit a radox rubber block inside the plunger, thus preventing a metallic contact between the two. This damps down the vibrations and no audible noise can be heard from the plunger. To prevent loss of movement of the compression rod, we filed away the portion that is tapered, making the end spherical. A piece of rubber the diameter of the hole in the plunger and approx. .125" thick was fitted. We have successfully damped the noise complained of on two of the Test Dept. cars by this method. We give a sketch showing how this has been obtained. Hs{Lord Ernest Hives - Chair}/G.W.Hancock. | ||