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).
The design, characteristics, and anti-wear qualities of a steering gear.
Identifier | ExFiles\Box 15\6\ Scan109 | |
Date | 27th May 1930 guessed | |
2. 6. Produce a gear that for a given steering load capacity carries the minimum of material and labour charges, both on machining and assembly; and which can therefore be produced on a competitive basis. An examination of the design, which has been standardised on the Acedes, and Acedes Magna cars, will indicate the principles involved, and why it fulfils to a remarkable extent the conditions already laid down. 1. Characteristics in use. In practice these gears have, after prolonged road tests, proved extremely successful. The action is smooth, light, and positive, with no sign of "Kick back". The frictional losses are low owing to the maintained oil film, and the absence of end thrust on the cover. The correct degree of reversibility sufficient to bring about a self centring action, yet still damp out road shocks, is obtained by varying the helix angle of the thread. This can be done without altering the ratio. 2. Anti-wear qualities. The contacting surfaces of the cam and follower have considerable area and load carrying capacity; infinitely more than the theoretical line contact normal to similar types of gear. In use the flattened surfaces of the half ball elements assume the mean shape of the adjacent sides of the cam track. In addition, an automatic oil feed takes place between the surfaces, on the principle of the Michell thrust block. Pressures on all bearings are kept well within normal engineering practice. | ||