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).
Two schemes for a Bensports timing gear layout, including details for overhead camshafts and a gear-driven blower.
| Identifier | ExFiles\Box 136\1\ scan0032 | |
| Date | 28th June 1932 | |
| X411 To R.{Sir Henry Royce} from E.{Mr Elliott - Chief Engineer} c. Sg.{Arthur F. Sidgreaves - MD} Wor.{Arthur Wormald - General Works Manager} Hs.{Lord Ernest Hives - Chair} E.6/HP.28.6.32. re Bensports Timing Gears. We attach herewith a blueprint of a rough lay-out showing the timing gear you described on the 'phone, and the scheme we had got out here for driving the overhead camshafts, and leaving provision for a gear driven blower alongside of the engine. The former scheme is shown in dotted lines, and the latter in full. The dynamo and water pump pinion is common to both. Each system of driving has the same number of gears, but we want to get the camshaft drive wheel down as low as possible, because the lower driven bevel is above the centre, and the upper driven bevel is below the centre. This gives the right relation for the camshafts to turn inwards on top. This latter is desirable as being the best mechanical direction for the rockers, and for retaining the oil in the camshaft casings, also the upper driving bevel, being below the centre can be run in an oil bath. It is undesirable for the camshaft driving wheel to project above the detachable cylinder head face. We would like the water pump rotation to be opposite to that of the crankshaft, as this gives direct tangential entry from the water pump volute into the cylinder block. With the dynamo pinion driven from the camshaft drive wheel three toothed contacts are loaded up with the oil pump torque instead of two. With the 5" diameter idler wheel the centre of the wheel comes low enough in position to avoid fouling the flywheel casing. The smaller idler wheel also cuts away less of the flywheel casing. The height of the cylinder block shown on | ||