Adjustments to the Wraith II brake system, including servo cam lever angles and pedal travel.
| Identifier | ExFiles\Box 7\7\ X 606 Brakes-page026 | |
| Date | 11th September 1936 | |
| Martindale x1044 Do we agree? 606 Rm {William Robotham - Chief Engineer} C.S. Ba. Ha/Fm. RMC. E {Mr Elliott - Chief Engineer} /HDY. {William Hardy} 1/HP.11.9.36. Wraith II Brakes. We find that partly as the result of the use of servo cam lever stops, the angle of movement that we show for the rear brake equaliser on N.Sch.4869 must be reduced to 37° from 41°, as at present shown for the idler lever. With 37° and a fully worn servo, i.e. with the cam lever stops shown by N.Sch.4897 in contact, the travel of the centre of the pedal plate should be 4.750" leaving a distance of .5" between the pedal and the board which is to be provided to guard against the pedal descending to the board should the rear equaliser fail - See E {Mr Elliott - Chief Engineer} /Hdy. {William Hardy} 3/HP.31.8.36. None of the pieces shown by N.Sch's 4869 and 4892 should be altered in any way as we may find means to avoid reducing the travel before the Wraith goes into production. All that is necessary at this stage is to show the 37° angle on any arrangement drawings that may be made. As regards the setting of the stop clearance in the Works, it seems to us that there is only one safe means of doing this, namely to connect up the brake rods forward of the equaliser leaving those behind disconnected, to slacken off the servo adjustment so that the cam levers are on their stops and to adjust the rod lengths so that with the equaliser idler lever on its stop the pedal plate is .5" from the board. One such means referred to above is to transfer the hand brake from the back to the front brakes. With this scheme there would be no need for any stops, and, therefore, no loss of pedal travel nor any dependence on accurate setting for safety. We propose to send a scheme showing means to actuate the front brakes by the hand lever to be tied out in parallel with the rear brake actuation. E {Mr Elliott - Chief Engineer} /HDY. {William Hardy} | ||
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).