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).
Page from a document explaining brake servo operation, fault diagnosis, and pedal pressure variation.
| Identifier | ExFiles\Box 178\1\ img094 | |
| Date | 1st July 1924 | |
| - 3 - Hs{Lord Ernest Hives - Chair}2/LGS.7.24. brake ropes, this is maintained until the brakes are released, although the servo is not going round. If there is any noticeable variation as regards equali- sation, or the amount of pedal pressure required, experimental test experience has been that this is most probably due to differences in the brakes themselves. Servos, once fitted up correctly, remain consistent and require very little attention. The leverage ratios are such that in the event of reasonable variation in the efficiency of the servo, the proportion of braking will not depart to any extent from the ratio before mentioned. If, however, the servo efficiency varies appreciably through some fault, then the distribution and braking may be seriously upset. Attached will be found instructions for testing the servo efficiency if found necessary. It should be remembered that if the front brakes are very effective on a car, the fault most probably will be due to the rear brakes. For instance, the rear brakes may have some oil on them, if this occurs, then more pressure will be put on the servo and so a greater pressure will be put on the front. Likewise, if the rear brakes are very effective, it may be that the front brakes are at fault. We expect that there will be variation within reasonable limits in the amount of pedal pressure required on various cars to obtain maximum braking. It is known on cars with rear (contd). | ||