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).
Testing two schemes, a pneumatic damper and friction plates, to overcome clanking in a braking system.
| Identifier | ExFiles\Box 16\3\ Scan065 | |
| Date | 18th September 1929 guessed | |
| -3- We have tried out two schemes of our own to overcome the clank. The first was to use a pneumatic damper between the 'T' arm and the front brake equalizing shafts. The one tried was too small in diameter to give satisfactory results the strokes being too great to give the results required. The idea is to offer no resistance to the movement of the brakes on application, but to damp the return of the front brakes, a release of the compressed air gradually allowing the leverages to come to rest obtaining the desired effect that Mr. Olley wishes to with his arrangement. The swinging arm as in all cases plays an important part, and adequate friction must be maintained. A load of 20 lbs. as at present used is sufficient. This scheme presents many possibilities and is worth going into with a correct designed damper. The other test tried was friction plates fitted to the 'T' arm making a definite load for the return of the levers on to the servo stops. The disadvantage of this method is that the same friction load for damping effects has to be overcome when applying the brakes, consequently more friction load has to be applied to the swinging arm to make the 'T' arm friction effective, otherwise it remains stationary and the friction arm along with the levers, operates instead. We found to overcome a quick release of the brakes a friction load of 20 lbs. on the 'T' arm and 25 lbs. load on the swinging arm was needed. With this setting there was no noise when the brakes were released but it was found to be too excessive for slow speed braking, the brake return springs | ||