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).
Damper control system for the B.V. series, proposing a pressure-velocity effect using bi-metal strips.
| Identifier | ExFiles\Box 151\2\ scan0381 | |
| Date | 6th February 1939 | |
| 1292 & 442 To By. {R.W. Bailey - Chief Engineer} from Rm {William Robotham - Chief Engineer} /AFM. {Anthony F. Martindale} c. Da. {Bernard Day - Chassis Design} c. Da {Bernard Day - Chassis Design} /Hdy. {William Hardy} c. HPS {Horace Percy Smith - Experimental Factory Mgr} /WB. {Mr Brazier / Mr Bell} Rm {William Robotham - Chief Engineer} /AFM. {Anthony F. Martindale} 1/MH. {M. Huckerby} 6.2.39. DAMPER CONTROL - B.V. SERIES. We have for some years now controlled the dampers of our cars by a pump unit which gives more pressure at high speed than at low speed, the mechanism used to give this effect being a governor controlled valve. This feature has been dropped on B.V. as being unnecessary, but, chiefly at Hdy {William Hardy} 's instigation, we have ascertained that a pressure-velocity effect can be reintroduced without much complexity by utilizing valve characteristics and bi-metal strips. The system is briefly as follows:- The hand lever on the quadrant moves by rods a shaft to which is attached a spiral bi-metal strip immersed in gear box oil. The other end of the bi-metal strip loads up the valve spring by means of a specially shaped cam. The valve is changed from a ball valve to a special conical valve, with normal seat. Payne's report gives curves showing the behaviour of the unit and indicates what temperature correction is necessary, but it is assumed that the precise shape of cam and valve would be left to the Experimental Dept. The pressure of 0, 10, and 20 lbs/sq.in. are purely arbitrary. No action is necessary immediately. Rm {William Robotham - Chief Engineer} /AFM. {Anthony F. Martindale} | ||