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).
The disadvantages of the Lentz Hydraulic Transmission system.
| Identifier | ExFiles\Box 136\4\ scan0010 | |
| Date | 15th January 1912 | |
| 524 January 15th. 1912. Lentz Hydraulic Transmission. -------------------- The main disadvantages to this system are as follows :- 1. The moveable ~~veins~~ vanes are kept in contact with the outer casing by means of a cam groove, and it is almost impossible to make an oil-tight joint between the edge of the ~~vein~~ vane and the inner face of the outer casing by this means. The accuracy necessary to make such a scheme an oil-tight job could not be obtained commercially, owing to the number of points and bearing surfaces which it is necessary to machine and fit exactly to obtain this result. 2. When the ~~veins~~ vanes are in their load-bearing position i.e. right out, they considerably overhang their supporting drum. The whole of the driving load is transmitted by these overhung ~~veins~~ vanes, and the slots in which they work would undoubtedly wear very badly. This point perhaps could be overcome by careful design, but the principle is not good. 3. A large amount of power is lost in hydraulic transmissions by the necessarily high velocity of the oil through the various ports and passages. This difficulty has been overcome for the top gear in several transmissions of this | ||