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).
Design and mechanics of the Bensport change gear tower and lever.
| Identifier | ExFiles\Box 86\4\ scan0020 | |
| Date | 28th October 1932 | |
| 228. BY.{R.W. Bailey - Chief Engineer} FROM HDY.{William Hardy} HDY.{William Hardy}/1/M.28.10.32. C. to SG.{Arthur F. Sidgreaves - MD} WOR.{Arthur Wormald - General Works Manager} HS.{Lord Ernest Hives - Chair} E.{Mr Elliott - Chief Engineer} DA.{Bernard Day - Chassis Design} BENSPORT - CHANGE GEAR TOWER AND LEVER. We send herewith N.sch.3556. which shews the above. The leverage of actuation of the synchro mesh cones is 3.9 compared with 5.5 on Peregrine, 5.28 on the 25HP., and 4.85 on the Phantom. With the direct operation of the cones from the sliders all of the leverage has to be found in the lever, and with a ball mounted lever the lateral movement at the knob becomes undesirably large with a high leverage. We anticipate that the engine clutch will have less inertia than that for the Peregrine. The gate is different laterally from our standard arrangement in that top and 3rd. positions are central, with 2nd. and 1st. away from the driver, and reverse towards the driver. There are no centralising springs for the lateral movement, but friction is provided on the ball to prevent rattles. The springs is intended to give .5 lb. of friction load at the lever knob. The lever being straight there can be no tendency to rotate the ball around a vertical axis, and for this reason the ball is located in the manner shewn, which is less perfect than our usual method, but is cheaper, and simplifies the whole ball joint. The tubular part of the lever is to be made from parallel tube ground taper on the outside. We imagine that this griding and the machining at the upper end of the tube will be done after the tuber has been presed into the ball, and consequently no great amount of adjustment for length need be provided on the reverse stop rod. The reverse stop is operated by lifting the knob, and is self-contained in that it needs no accurate setting with the exception of the adjustment of the length of the rod. HDY.{William Hardy} | ||