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).
Modifications and specifications for thin leaf type front springs.
| Identifier | WestWitteringFiles\M\October1924-December1924\ Scan7 | |
| Date | 10th June 1924 | |
| TO BY.{R.W. Bailey - Chief Engineer} FROM R.{Sir Henry Royce} Copy to - OJ. Copy to - HS.{Lord Ernest Hives - Chair} Copy to - DA.{Bernard Day - Chassis Design} Copy to - E.{Mr Elliott - Chief Engineer} re. FRONT SPRINGS. X2628 X9410 THIN LEAF TYPE. With regard to the sample front spring (Woodhead) brought here by HS.{Lord Ernest Hives - Chair} last Friday, and which was examined by DA.{Bernard Day - Chassis Design} and E.{Mr Elliott - Chief Engineer} we think we should try if possible to do without the facing operation on the lugs carrying the clips, and its consequent reduction of section. We cannot see why these lugs should not be sufficiently good and flat from the forging operation. We agree to the adoption of the pattern of spring as inspected, as I understand it conforms in other ways to our requirements, such as in number of leaves and thickness of top plate, and I agree that we can postpone until a more suitable time the adoption of the taper and with lugs set further back. With regard to HS.{Lord Ernest Hives - Chair} experience of the front axle coming on to the buffers too frequently, we ought to make the following modifications:- (1) Use as much rubber as it is possible to get in, that is to say, no packing plates between the rubber and the frame. (2) Adopt an average clearance of 1 1/4". This will require a 2 1/4" rubber. If the car still bumps too much we must have more initial deflection or a stiffer spring. We do not desire excessive friction in the shock dampers. We prefer the friction within the spring so as to steady and control the axle torsionally. We believe that for safety in steering the 20% stiffer spring is preferable, and which we have arranged for the high speed cars. It will be remembered that we have suggested two ratings for each strength of spring stocked. I understand that on cars which have run in France the frame becomes somewhat bent up on the lower flange where it carries the buffer. Therefore we have asked Mr. Day to design some form of stiffener for this point. R.{Sir Henry Royce} | ||