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 report on the performance and testing of Peregrine brakes.
| Identifier | ExFiles\Box 179b\2\ img198 | |
| Date | 10th December 1932 | |
| R.{Sir Henry Royce} From Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls} c. to SG.{Arthur F. Sidgreaves - MD} c. to SoT. c. to K.{Mr Kilner} c. to Ry. c. to De. c. to Hdy.{William Hardy} PEREGRINE BRAKES. The attached sketch shows the arrangement of the brace layout tried out on 3. Peregrine car. The brakes proved to be very effective requiring only a light pedal pressure. The brake clearances were set at .015 at the shoe centre. This was in order to reduce as much as possible lost movement at the brace pedal and servo. The set up of the pilot shoes was reduced from .020 to .007 considerably reducing the sponginess of the system. The amount of direct bracing was increased from that shown on the N.scheme to the same as both the 40/50 and 21/25. The amount of front bracing was also greatly increased, with by altered leverages and the use of a 4" servo cam. The total brace units for a given pedal pressure were therefore higher than we have previously had on any car. The amount of wear of the linings measurable after a run of 500 miles including the worst hills in Devon and North Wales was .0015 at the front shoe centres and Nothing on the rear brakes, and hence nothing at the brake pedal. The toggles in the brake drum between the cam and the shoes were found to be buckled after the run. We are stiffening these and also the rear brace cam shafts and the shafts in the front axles. The sponginess in the system should then be very small. Coupled with the increased stroke of the larger servo we should be able to run with the amount of bracing tried on this car without the necessity of frequent adjustment, or the possibility of the servo reaching the end of its travel, which on this car it was very near to doing. Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls} | ||