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).
Acceleration testing machines and various types of shock absorbers.
| Identifier | ExFiles\Box 43\2\ Scan094 | |
| Date | 8th February 1926 | |
| Oy3-E-2826 -3- February 8, 1926 which may either be set on the floor or carried on the knees of the passenger. The Newton machine measures total reversal of acceleration per mile, (the unit being a "Newt" equivalent to 2g or 64.4 ft./sec.2). The Norton machine draws a picture of accelerations (not displacements) on a photographic film. Both are useful. The Newton is the more practical for routine testing. The Norton brings out most clearly certain specific defects. For example, it showed by the difference between floor and seat readings on a given stretch of road that the cushions in particular instances were building up or exaggerating the vertical accelerations of the car. Why not let us get a couple for you? We are discussing getting at least a Newton machine for our own use. Front Shock Absorbers. Since the date of the Mack riding test we are making the front shock absorbers carry 50 lbs. on the ball by means of a longer and stronger compression spring A-7352 (attached print). This has been an improvement which we believe is necessary with 33x6-3/4 6 ply tires on 21" wheels, which we now fit on all cars. We are also trying to get Thermoid shock absorber cups of a hardness such that they will not squeak. Flentje Shock Absorbers. You will notice the reference to "Flentje" front shock absorbers. This is a double-acting hydraulic shock absorber made by a small concern in Boston. It is well made and effective and does not produce such violent jerks as the Houdaille, but is poorly designed. I do not think we could possibly use it standard, but we are going to try it on 12-MC and if it is effective in making it ride better and curing "shimmy" I will send you a pair. In common with the Houdaille it has the defect that for very rapid agitations like driving over car tracks at a fair speed it produces a rough feeling as though one had no springs on the car at all, and causes rattles in the radiator and bonnet. | ||