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).
Description of a variable speed gear mechanism using oil pressure to create a coupling and drive for an automobile.
| Identifier | ExFiles\Box 147\4\ scan0161 | |
| Date | 16th May 1941 guessed | |
| continuous to set up a pressure or resistance in the oil impelling the rotor to increase the speed of the latter. When this pressure or resistance exceeds the inertia or resistance to motion of the driven shaft the crown wheel of the latter is forced to rotate through the drive from the bevel pinions and said shaft accelerates until it is revolving in unison with the drive shaft, rotor and differential gear. If required reverse gear of appropriate design may be interposed in the drive or driven shaft. The mechanism described provides a uniform and smooth transmission under all conditions and the oil pressure or resistance creating coupling comprising the combination of the fixed casing and vaned rotor may be designed in accordance with the horse power of a particular engine to effect a gear ratio commensurate with the capacity of the engine. The mechanism hereindescribed has a wide range of selective speeds between the drive and driven shaft variable from the lowest gear ratio for automobile driving purposes up to approximately 2 to 1. oOo | ||