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 Lockheed-Gates Booster types and a performance comparison chart against conventional vacuum servos.
| Identifier | ExFiles\Box 120\2\ scan0346 | |
| Date | 22th June 1938 guessed | |
| LOCKHEED FLUID BRAKE EQUIPMENT Sheet 20. system. The master cylinder has a suitable balance chamber on the forward side connected to the pedal master cylinder and thus the pressure exerted on the brake pedal is added to that generated by the boost, whilst this arrangement also provides a hydraulic balance which permits perfect control of the Booster and at the same time automatically compensates for any variation in the co-efficient of friction of the plates and their followers owing to changes in atmospheric conditions. The Lockheed-Gates Booster is made in three different types :— (1) The “Gear Box” type, where the booster is coupled direct to the rear end of the gear box. (2) The “Transmission” type, which is mounted round the propeller-shaft and takes the place of the centre bearing where a divided shaft is employed. (3) The “Separate” type for an independent drive. This form is intended for use on trolley buses, where it would be coupled to the end of a motor shaft, or in cases where it is impossible to employ either of the propeller-shaft types. Installation drawings of all three types are shown on the attached sheets. It will be appreciated that by simply altering the number of plates, the clutch cylinders and or the main master cylinder, a wide variety of efforts can be obtained from the same model of booster. The performance curve opposite clearly illustrates the increased boost given by the Lockheed-Gates Booster, as compared with normal vacuum boosters. As the amount of torque obtained is in completely linear ratio to the pedal pressure, it is necessary to snub the booster off when a certain line pressure has been generated in order to avoid the possibility of damage occurring ; the curve clearly shows the point at which the snub valve functions. Made under one or more of the following British Patents:— 439882, 439923, 457085, 476559, 477137 and equivalent Foreign Patents. Other Patents pending. LOCKHEED FLUID BRAKE EQUIPMENT Sheet 20. TYPICAL OUTPUT CURVES FOR LOCKHEED-GATES BOOSTER AND CONVENTIONAL VACUUM SERVO Graph Labels: Y-Axis: MAIN LINE PRESSURE LBS. ☐. X-Axis: PEDAL EFFORT LBS. Curves: BOOSTER SNUB VALVE ACTS, BOOSTER. USING 5 PLATES, L.G. BOOSTER (OLD), VACUUM BOOSTER, LINE PRESSURE WITHOUT BOOSTER. | ||