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).
Description of the R.R. Automatic Boost Regulator and its operation.
| Identifier | ExFiles\Box 179\2\ img151 | |
| Date | 11th January 1932 | |
| ORIGINAL BP. From Ha/FRL c. to Dr. Rs.{Sir Henry Royce's Secretary} c. to DV. Fl. c. t Lr.{Mr Ellor} Ha/FRL.3/MA.11. 1. 32. Y4033 DESCRIPTION OF R.R. AUTOMATIC BOOST REGULATOR. The boost regulator is a device by which the boost of the supercharger is controlled, and automatically maintained to its rated pressure, up to the rated altitude of the particular engine. Briefly, the system consists of an operating, or relay piston, working in a cylinder, and being able to traverse the range of the cylinder. The relay piston is coupled to the throttle operating shaft, through the medium of a differential gearing, which will allow independent movement of either the relay piston or throttle lever, or both, according to the movement or fixture of the pilots operating lever. For the power medium of the relay piston, the pressure difference across the supercharger is utilised, excepting at small throttle opening when the pressure side of the blower falls below atmospheric, and a changeover cock in the system opens a port to atmospheric pressure. The relay piston movement is controlled by an aneroid operated piston valve, which regulates the ports in the piston valve bush, to exert suction or pressure of the supercharger to either side of the relay piston, and regulate the throttle opening according to the boost requirements. The aneroid unit is a sylphon tube, exhausted to ½ lb/sq.in. press. abs., and is then balanced by a spring against atmospheric pressure, in order to ensure deflection of the sylphon for the slightest variation of the boost pressure with which the sylphon is in direct contact. The deflection of the sylphon being transmitted to the piston valve, to operate the suction and pressure ports to the relay piston. OPERATION. The aneroid or sylphon is permanently open to the boost or pressure side of the supercharger, and at small throttle openings this pressure is lower than atmospheric, resulting in the aneroid due to its balance, exerting a downward pressure, and lowering the piston valve. | ||