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).
Test report on the latest pattern of American-fitted Lovejoy delay-action shock absorbers.
| Identifier | WestWitteringFiles\Q\2-July1927-September1927\ 17 | |
| Date | 8th July 1927 | |
| To R.{Sir Henry Royce} from Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} c. to BJ. Wor.{Arthur Wormald - General Works Manager} c. to RG.{Mr Rowledge} E.{Mr Elliott - Chief Engineer} c. to DA.{Bernard Day - Chassis Design} BY.{R.W. Bailey - Chief Engineer} c. to OY. ORIGINAL Hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}7/LG1 8.7.27. LOVEJOY SHOCK ABSORBERS. X832 We have tested the latest pattern of these dampers as fitted in America. They are of the delay-action type. The delay action is obtained by preventing the high pressure valve coming into action until the axle has a movement of between 4 to 6", and also by allowing somewhat plentiful leakage around the valves. The maximum poundage obtained is high, being 200 lb.s approx. at the lever end up to 4" stroke - 275 lbs. approx. for greater movements. The only reason such a poundage can be endured on the rear of the car seems to be owing to the fact that such a load only exists momentarily during the stroke. Even at low speeds the working chamber does not fill up fully. This is what one would expect, as atmospheric pressure is relied upon to induce the oil to enter the cylinder. Therefore for low speed oscillations the axle is only damped for about 80% of its movement and at high velocities for about 50% of its movement. The actual peak maximum damping load is not affected appreciably by either temperature or speed of operation i.e. the fall off in volumetric efficiency about balances the increase in oil velocity. contd :- | ||