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 evaluating a third-party shock absorber design and its claimed performance.
| Identifier | ExFiles\Box 152\2\ scan0186 | |
| Date | 8th April 1940 | |
| 1293 Rm{William Robotham - Chief Engineer}/Clm.{D. D. Clapham}7/JH. 8th. April. 1940. Clinton D Cory Esq., Clutsum & Kemp, Coalville, LEICS. Dear Mr. Cory, It was very kind of you to bring Mr. Piazzolla over to see us, and we have now examined the claims made for his shock absorber. We are sorry to say we do not believe it could work as he claims. It must be realized that there are two very different frequencies with which a damper has to deal. One is the frequency of the car about the axles which is about 80 - 100 cycles per minute and occurs when traversing a wavy road. The other is the frequency of the axles about the car, such as over potholes or similar obstacles, this is a much higher frequency, about 500 - 600 cycles per minute but the amplitude may be quite considerable still so that in this damper the damping load would be very high, much too high in fact. We ourselves are convinced that it is impossible to make a satisfactory damper without a blow off valve to take care of the high frequency large amplitude movements and so prevent the damping from becoming excessive under these conditions. We return Mr. Piazzollas literature herewith together with a short note indicating what we consider are the faults of the damper. Cont'd.{John DeLooze - Company Secretary} | ||