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).
Letter from an inventor offering a new 'torque booster' transmission system for consideration and trial.
| Identifier | ExFiles\Box 15\6\ Scan073 | |
| Date | 29th October 1928 | |
| JOHN F.{Mr Friese} N. CRAIG. TELEPHONE, GERRARD 2968. 6421. X728. 9, REGENT STREET, LONDON, S.W. 1. October 29th 1928. For attention of Mr Hines. Messrs. Rolls-Royce Ltd., Derby. Dear Sirs, I should like to offer some preliminary details of a new transmission system for your consideration. Then if you are interested in what the invention will do, it can be fitted to one of your cars for comparative tests. The torque booster, which replaces clutch and gear-box, is arranged to transmit direct drive under all ordinary loads and conditions. There are actually no gears or ratchet mechanism, but there is a hydraulic drive which assists the effort of dealing with exceptional loads and permits relative motion between driving shaft and driven. The differential feature ensures that only the additional load is dealt with by the booster, as in every case the full torque produced by the engine is directly transmitted. The fact that only a proportion of the power is transmitted indirectly means a saving in size of the transmission, and a very efficient device. Further, the fact that in direct drive not a single part of the "gear-box" is in motion, finally overcomes the objection to the use of a gear which is variable. As there is a neutral position when engine revolutions are allowed to drop sufficiently, and as the bridled control-spring puts the gear into action when the normal direct-drive torque is exceeded, you have a quite perfect transmission element superseding clutch and gearbox. The only external control is a reverse rod which may be pedal operated. As an inventor I do not expect drawings to be taken very seriously, because a critic has no time to go into facts as fully as a good designer. But if you feel that the device could be used in your production, I should be pleased to provide a booster unit for trial, which would be made to suit your chassis and power-curve. You would then be very well able to increase the gap which exists between the Rolls-Royce and other first-class cars, as no details of the new device have been circulated. | ||