Letter detailing an investigation into a clanking noise produced by servo-operated brakes upon release.
| Identifier | ExFiles\Box 12\5\ 05-page122 | |
| Date | 12th July 1929 | |
| OY-10 Mr. A. {Mr Adams} F. {Mr Friese} Sidgreaves, Rolls Royce Ltd., London, England. cc - Mr. Bailey Mr. Hives July 12th, 1929. Dear Mr. Sidgreaves: BRAKES Clank on release. (1) As you are no doubt aware one of the persistent minor complaints regarding the servo operated brakes is that they are liable to produce a loud clank on release. Height of suspension point on tee lever. Some time ago we investigated this as thoroughly as we could (and I recall that Mr. Hives also sent us a report on the same subject at about the same time.) As a result we found that the presence or absence of "clank" depended on the relative closing of the stops for front and rear brakes when pedal was released that is - If the front brakes came against their stop before the rear brakes, no clank would occur, and vice versa. (2) It was then easy to see the reason, that is that as soon as the rear stop "closes" the driven lever of the servo cam-levers ceases to move, and further release of the pedal causes the servo halos to separate, when the front brakes (operated by servo only) "collapse" against their stop. We found that the actual noise came from various pieces, the front stop, the driving pins and bent pulling levers on the servo, etc. so that to cushion this noise out of the mechanism was scarcely practical. --continued-- X7420 | ||
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).