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).
Technical description of a servo mechanism's operation, adjustment, and maintenance.
| Identifier | ExFiles\Box 178\1\ img086 | |
| Date | 8th July 1924 | |
| - 5 - The 3 pins (G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 72459) are to prevent the two plates rotating independently of each other. These pins should work perfectly freely and accurately in the bushes because they have to transmit half of the torque given out by the servo. Every part must work quite freely - anything which tends to bind must be corrected. A stop to limit the angular movement of the servo is fitted to the top of the outer plate and is to prevent damage to the mechanism in case it is operated with some part of the brake linkage disconnected or breakage of pull ropes. It has 68° backward travel from its mean position and 84½° forward. This stop may also be used to check the adjustment of the pull ropes. There should be no free movement of this stop, if there is, it indicates slack in the pull ropes and should be corrected. Oilers are fitted to those parts requiring lubrication but great care must be exercised to keep oil away from the friction linings as the correct working and proportioning of the whole system relies upon these friction linings running dry. It is very improbable that oil will reach these linings under normal conditions. Adjustment. An adjustment nut is provided at the end of the servo shaft. By turning this nut the inner servo plate can be moved in relation to the outer plate. Therefore by this means the clearance of the plates can be adjusted. The nut has a serrated locking device which, when the required clearance is contd. | ||