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).
Notes concerning the design of valve springs as affected by spring coil vibrations.
| Identifier | ExFiles\Box 56\2\ Scan095 | |
| Date | 28th August 1930 | |
| NOTES CONCERNING THE DESIGN OF VALVE SPRINGS AS AFFECTED BY SPRING COIL VIBRATIONS. The following symbols are used :- Diameter of wire = d (") " " coil = D (") Number of effective turns = k Density of wires (lbs. per inch³) = w Free length of spring = L (") Set up length of spring = L₀ Fully compressed length of spring = L' Modulus of shear of material of wire = C (lbw/sq.") Load on spring = W (lbw) Set up deflection of spring = δ₁ Fully compressed deflection of spring. = δ₂ Stress on material = f (lbs/sq.") It can be shown that for the spring in the state of compressed rest f = (Cdδ)/(πD²k) W = (Cd⁴δ)/(8D³k) It has further been shown that the fundamental natural frequency vibration of a spiral spring fixed at one end is N = ¼ √(E/M) | ||