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).
Different types of chassis lubrication systems, including continuous feed and vacuum-operated oil pumps.
| Identifier | ExFiles\Box 27\1\ Scan329 | |
| Date | 10th September 1929 guessed | |
| - 4 - B. OTHER TYPES OF CHASSIS LUBRICATION (1) Continuous feed systems, are having to be developed by Bijur as well as others for the cheaper cars. The worst is probably the type which uses a "jiggle-pump" worked by a rough road. This is found very uncertain in its action, varies with weather etc. Main trouble with continuous feed system is their inability to feed drip plugs satisfactorily in warm weather unless all the plugs are about on the same level. In zero weather as much as 100 lbs./sq.in. pressure may be read in the line, and at 100°F it may be impossible to find any pressure at all. By using a very heavy oil it is possible to get a minimum of 1 lb. pressure in summer. All these systems drip with car standing. Such a heavy oil is useless in cold weather as we know from our own experience. By restricting the discharge ranges of the drip plugs (No 5 to No 0) from 30 to 1, to about 4 to 1, and making the total drip plug resistance not less than 4 times that of a normal system, also by keeping all the drip plugs about the same level, continuous systems can be made to work well enough for cheap cars. The drip plugs have unloaded flap-valves without spring tension instead of present non return valves. (However, as the result of experience with continuous systems, Bijur have recently reduced the back pressure of their non return valves in standard drip plugs from 10-15 lbs./sq.in. to 3.5 lbs./sq.in.) With regard to continuous feed T. agrees that our idea of giving a much larger shot of oil at much longer intervals than even present standard system, is desirable where parts are well made, but considers the average shackles are not sufficiently well made to run for more than 50-100 miles without oil. (2) Vacuum Operated Oil Pump - The Bijur Vacuum-operated diaphragm-pump is being used with continuous feed systems, as well as with accumulator systems. The diaphragm is connected either to the vac. feed tank or direct to the manifold, on cars without vac-feed. In the latter case the oil pump plunger is 3/16" dia. x 1/8" stroke giving .056 cc per stroke, against about double this when connected to the vac. feed. - continued - | ||