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).
Recommendations for a car's gearbox, oil pump, and control system.
| Identifier | ExFiles\Box 99\3\ scan0044 | |
| Date | 29th December 1937 | |
| - 2 - Da{Bernard Day - Chassis Design}/Hdy.{William Hardy}18/C.29.12.37. (3). cont'd.{John DeLooze - Company Secretary} to the 25/30. We think that this car, being obsolete, should be left out of consideration. (4). We think that the recommendations given in Rm{William Robotham - Chief Engineer}/Les.8/AP. 7.12.37. should be tried out, with the exception of the use of the gearbox oil. We consider that the advantages attached to the use of a separate reservoir for the control oil are important enough to justify the cost of the reservoir. [Handwritten note in the left margin] Cost of reservoir would not be much? Rm{William Robotham - Chief Engineer} [/Handwritten note] We suggest that the gear oil pump is embodied in the reservoir above the oil level in order to avoid trouble with glands. The driving spindle can pass through the pump and out of the reservoir to provide a drive for the speedometer. In this case the spindle will have to run at approximately one quarter engine speed and can be driven by a spiral gear mounted above the centre line of transmission and meshing with the servo worm on the 3rd motion shaft. No extra gears are required for the control pump and the height of lift of the oil for priming is only about three inches at the most (i.e. reservoir nearly empty). It appears likely that a small leak will have to be provided to allow the pump to prime, as except for the hand control valve, the circuit on the delivery side is closed and consequently with no leak the pump would have to generate whatever pressure was set on the control valve which it would probably not be able to do when full of air. If it is found that a velocity pressure rise characteristic in the control system is desirable (in addition to whatever velocity pressure there may be in the dampers) there is the kinetic energy restriction tried by Rm.{William Robotham - Chief Engineer} on the dampers some ten years ago, which was, we believe, relatively free from viscosity effect. This restriction consisted of a number of baffles in series, each having a hole offset from the preceding hole for the passage of the oil. For a given restriction pressure the holes were larger than the diameter required with a single hole. Such a restriction might prove to be a satisfactory substitute for the governor. Da{Bernard Day - Chassis Design}/Hdy.{William Hardy} | ||