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).
Nomogram blueprint for determining the cubic capacity of engine cylinders.
| Identifier | ExFiles\Box 77\5\ scan0124 | |
| Date | 27th April 1918 | |
| To R.{Sir Henry Royce} from EFC. c. to CJ. " " E.{Mr Elliott - Chief Engineer} " " By.{R.W. Bailey - Chief Engineer} " " FP.{F. Potts} " " Da.{Bernard Day - Chassis Design} " " EH. EFC1/AT27.4.18. X.3290.-RE NOMOGRAMS. Herewith please receive a blueprint of a "Nomogram" for the determination of the cubic capacity of engine cylinders. We think this will be found useful as a direct graphical comparison between the bore, stroke and cubic capacity of any cylinders which it may be desired to represent on this chart. The scales are logarithmic and are so arranged and placed, that the determination of the cubic capacity of a cylinder, of known bore and stroke, involves nothing more than the ruling of a fine line with a straight edge from a point on the bore scale, corresponding to the bore, to a point on the stroke scale, corresponding to the stroke. It will be found that the point where this line intersects the cubic capacity scale gives, as accurately as may be reasonably expected, graphically the cubic capacity of the cylinder. It will be noticed that each of the three scales is given in both English and Metric units, so that direct conversions are automatically carried out when required. We have represented on the Nomogram lines corresponding to the "Falcon", "Eagle", "Condor" and Mercedes engines, and it will be noticed that the stroke bore ratios are also represented graphically by the inclinations of these lines. (Contd). | ||