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).
Faulty working brakes, specifically the seizing of the rear axle mechanism and related lubrication issues.
Identifier | ExFiles\Box 32\2\ Scan024 | |
Date | 25th April 1921 | |
X.3458 c.c. to Mr. [illegible] c. to Hs.{Lord Ernest Hives - Chair} c. to L. EP{G. Eric Platford - Chief Quality Engineer}1/F25.4.21. A.T. X3458 RE. FAULTY WORKING BRAKES. During the last few months we have had a considerable number of complaints from our Depots of the brake mechanism on the rear axle seizing up, but we have been unable to obtain a correct analysis of the cause of this trouble as we have not had similar trouble on cars with which we have come in contact, as the information we have obtained from the Depots is not satisfactory otherwise than to state that the bushes have seized on the actuating shafts. They request that more clearance be given, as they point out that the attention so far as lubrication is concerned has been satisfactory. We have recently had one or two post-war cars come into our hands for attention, on which the brakes have not been satisfactory. In one case the shafts were inclined to be seized up, and in the other case the brake links were overoiled, and a thorough investigation was therefore made. With regard to the fitting and the clearances of this mechanism, this appears quite satisfactory to drawing, but the lubrication of the bush in the brake bracket does not appear satisfactory. When new, the oil which is forced through the lubricator and passes through the toggle mechanism and the bush fairly freely, but when the car has been in service for some time, the external part of the bush seems to get clogged with road dirt, etc. and the oil then passes freely through the toggle mechanism and does not pass through the bush. Our general instructions in dealing with these features have been that this part should be lubricated fairly often, and not too literally, as if an oil film in the bush is maintained, water and dirt will be excluded. If, however, the oil and dirt get into this bush and the lubrication is then freely used, the oil passes too freely through the toggle mechanism and gets on to the brake shoes, causing the brakes to be ineffective. We feel that this feature is one which requires attention. Could not the oil supply to the toggle mechanism be restricted so that a more definite flow of oil may be maintained through the bearings? This might be obtained if the oil supply hole was directly on the part of the toggle which took the load, but the fixing of the hole in this position seems impracticable, and the only alternative seems to be a definite restriction unless such a feature was lubricated separately. | ||