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).
Suggested design for a combined delivery and relief valve on an air pump, using small sylphons.
| Identifier | ExFiles\Box 78\1\ scan0255 | |
| Date | 25th September 1920 | |
| SUGGESTED USE OF SMALL SYLPHONS FOR COMBINED DELIVERY AND RELIEF VALVE ON AIR PUMP RELIEF VALVE SET TO BLOW OFF AT SAY 6 LBS VENTS [ORDINARY FORM OF RELIEF VALVE MIGHT BE USED] PIPE TO OUTSIDE AIR, TO CARRY GAS FUMES AWAY FROM ENGINE PUMP HAS SMALL CLEARANCE VOLS. DELIVERY VALVE LIMITS PRESSURE. To TANK. DELIVERY VALVE AREA OF PORT A IS TO AREA OF SYLPHON AS 2 1/2 TO 1. IT TAKES 5LBS TO LIFT VALVE BY AREA OF PORT A ON DELIVERY STROKE WHEN TANK HAS NO PRESSURE. 2LBS AT A AND B TOGETHER WILL LIFT VALVE [THUS LIMITING WORKING PRESSURE OF TANK]. WHEN PUMP IS STATIONARY AND NO PRESSURE AT A, TANK WILL BLOW OFF AT 3.3LBS. IF PISTON DOES NOT LEAK FAST ENOUGH TO CARRY AWAY THE PRESSURE, RELIEF VALVE WILL OPEN AT 6 LBS. [BY THIS SYSTEM THERE IS STILL ONLY ONE VALVE TO LEAK AIR OUT OF THE PETROL TANK, AS AT PRESENT] VENTS Oy | ||