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 the design of pistons used in the oil relay ignition governor.
| Identifier | ExFiles\Box 65\1\ scan0053 | |
| Date | 1st January 1924 | |
| X8685 To BY/Shn. from Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} Hs{Lord Ernest Hives - Chair}/Rn{Mr Robinson}1/LG2.1.24. OIL RELAY IGNITION GOVERNOR. X8685 The oil relay ignition advance is now a working proposition. We recommend the following points should be noted :- (1) Piston E.72503 is to be made of M.S., diameter .618". We have actually been running with oil grooves half the specified depth on this piston to facilitate cleaning. We recommend that the depth of these grooves is reduced therefore. Though this piston dia. is satisfactory from the oil relay point of view, it may cause unforeseen difficulties with the main oil pressure. We therefore suggest that no large quantity should be made unless the outside dia. is left at .624 for finishing. (2) We wish, if possible, to specify a length for rod E.72649 which will be satisfactory for all relays. <strike>piston E.72503</strike> We should therefore suggest that on piston E.72503 the limits for the distance between the ball seat which locates this rod, and the top of the piston trunk (which dictates the movement of the relay), should be kept as small as practicable. In addition, to conform with this, that on piston E.72509 the distance between the top of the inside exhaust groove and the bottom of the inlet groove in relation to the face locating this piston in its zero position, should be given reasonably fine limits. contd :- | ||