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).
Technical drawing detailing the specifications and dimensions for a valve spring with variable coil spacing.
| Identifier | ExFiles\Box 96\2\ scan0198 | |
| Date | 5th January 1936 guessed | |
| SPACING OF COILS. DIMN'S A.{Mr Adams} B. & C. SHOW HOW THE SPACING BETWEEN COILS GRADUALLY INCREASES. IT IS ONLY THE SPACING OF THE FIRST THREE COILS THAT VARIES IN THIS WAY. THE SPACING BETWEEN THE REMAINING COILS SHOULD BE EQUAL TO ONE ANOTHER. 1.940 FREE LENGTH A.{Mr Adams} = .050 B. = .100 C. = .200 1.100 DIA (INSIDE) .975 DIA (INSIDE) THE END COILS TO BE GROUND SQUARE WITH AXIS OF SPRING. TO PRODUCE A GROUND FINISH OVER ALMOST THE COMPLETE DIA OF THE END COILS. RIGHT HAND WINDING. NO ENAMELLING. TABLE: DIA. OF WIRE: .160 Nº OF WORKING COILS: 5 TOTAL Nº OF COILS: 6 1/2 VALVE COMPRESSED LTH.: 1.525 CLOSED LOAD IN LBS: 45 +1/4oz -1/4oz RATE LBS/INS: 109 LENGTH OF WIRE: 24.5 INS VALVE SPRINGS MATERIAL Nº PER SET 12. RM.{William Robotham - Chief Engineer} 260 | ||