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).
Solutions for radiator jellying, body mounting, and reducing frame vibration using rubber insulation and dampers.
| Identifier | WestWitteringFiles\U\2January1930-September1930\ Scan103 | |
| Date | 5th May 1930 | |
| HS{Lord Ernest Hives - Chair}/RM.{William Robotham - Chief Engineer} ) FROM R.{Sir Henry Royce} (At Le CanadelHenry Royce's French residence.) ORIGINAL! x7380 x457 x5380 x2250. x7830 x7005. x5830 x7005. CAR WORK - RADIATOR JELLYING, BODY MOUNTING, ETC. Apparently this difficult problem has now been solved sufficiently well for the present by HS{Lord Ernest Hives - Chair} idea of mounting the radiator flexibly as regards lateral control at the top, that is, I understand if one goes up to the radiator and gives it a powerful push sideways it can be pushed over without taking the frame with it all the way. This, E.{Mr Elliott - Chief Engineer} points out, is the principle of an inertia damper, and does not of necessity require friction, and should give two small periods instead of one big one. I think HS{Lord Ernest Hives - Chair}/RM.{William Robotham - Chief Engineer} has done well on this and it now seems only necessary to make it into a lasting design, if it is not already so. My dampers have always seemed to require friction and perhaps this scheme would be better for general use if we added some friction somewhat in the same way as the engine dampers used with the 3 point suspension. One would suppose that the frame had torsional period rather high when the radiator is removed, and when the radiator is spring mounted still higher. If this is so we ought to see that it is not out of step with the axle with tyres at all pressures, because there is little doubt we ran into this trouble by the period of the frame etc matching that of the tramping speed of the road wheels at normal tyre pressures, and we could only get away from it by lowering the natural torsional period below that of the axle. Even when we had done this certain stiff bodies raised this speed until we were approximately the same as with the cross in the frame. This brings us to the point that we ought to have some uniformity in body mounting, and I am convinced that the underframe EV{Ivan Evernden - coachwork} introduced with complete rubber insulation of the body from the frame is extremely valuable, and should be universal. It reduces the engine and road vibrations that reach the body from the frame. We have then:- (1) The power unit and gearbox insulated from the frame (rubber.) (2) The body insulated from the frame (rubber.) (3) The passengers insulated from the body (good cushions.) All of which are possible, and should be uniformly carried out. This has not much bearing on booming, which may come through the air. R.{Sir Henry Royce} | ||