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).
Proposed body suspension designs, experimental body construction, and patent considerations.
| Identifier | ExFiles\Box 14\8\ Scan293 | |
| Date | 2nd March 1931 guessed | |
| - 4 - Possibly the English rear body suspension which can add lateral loads to the frame is a contributory cause of this, and this will be absent with our proposed 4 point suspension, where our rearmost point of body suspension is much further forward and is taken at a point much closer to the torsional neutral axis of the straight portion of the frame. We believe we should get some valuable information on this matter if we mounted a body of this type designed for a wide axle on a chassis fitted with a narrow axle. We are now building at Brewsters two experimental bodies of this type. In the first the sill is carried over the brake drum as sketched in pencil in enclosed print of DL-89, and the second is more in conformity with DL-89. In the first it is necessary to move the point of suspension forward to clear the brake drum, so this is moved forward to a point corresponding to the crossmember of the subframe which passes over the middle of the battery and this crossmember is inserted for support. The sills are being made 5-1/2" deep on the first and the overhang from the rear end is considerably higher than we should get with the second type as drawn on DL-89. The second one is now being laid out and will have the support 9" ahead of the axle on the heelboard crossmember. In the first, I think there is little doubt that with the increased rear end overhang and comparatively shallow sill, the latter will be very highly stressed, but we are particularly interested in seeing how far we can go in raising the stresses in the sill without disastrous effect on the body. In the second, the sill will be made to approximate to the flexural rigidity of the subframe. In this case, it is to be noticed that the body crossmember over the battery can be omitted altogether as unnecessary giving us the possibility of using an American 12 volt battery in a single unit in this location, which will save us from the necessity of importing batteries for replacements. In this new type of body construction, we believe we have something which is a very big advance over anything done yet. You will notice it is a combination of Mr. Royce's original ideas, the subframe and other schemes. We are very anxious to do whatever we can in covering this with patents but nothing has yet been done in this direction. While it is necessary for us to submit this to England to illustrate the reasons for changes, we are likely to ask for, and also to get their sympathy with our views, yet in view of any possible patent situation it is not desirable to broadcast these ideas unnecessarily, particularly to English Coachbuilders who may at some future date be operating in competition with ourselves. M / Encl. Btn. | ||