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).
Page of calculations for engine connecting rod balancing, considering centre of mass and moment of inertia.
| Identifier | WestWitteringFiles\M\2October1924-December1924\ Scan3 | |
| Date | 6th October 1924 | |
| Contd. -15- EFCL /T6.10.24. The centre of mass G of the con. rod is in the line XP and at a distance b beyond P and the division of the total mass for the purpose of complete linear balance is such that Mp = a / (a - b) M (i.e. greater than M) Mx{John H Maddocks - Chief Proving Officer} = b / (a - b) M (i.e. negative) a being the distance XG and b being the distance PG, the con. rod length now being a - b. The Mx{John H Maddocks - Chief Proving Officer} mass, being negative, can, by suitably placing G, be made to compensate the positive mass of the actual pure reciprocating parts (which have not previously entered into consideration) so that reciprocating balance is effected. Revolving balance is then effected by balancing Mp. (see diagram) The equi-momental system of three massive particles for this case is Mx{John H Maddocks - Chief Proving Officer} = k^2 / (a(a - b)) M (positive) Mp = k^2 / (b(a - b)) M (negative) Mg = (1 + k^2/ab) M (positive) so that in effecting complete linear balance in this case we have left unbalanced a moment of inertia about G of masses Contd. | ||