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).
Promotional and technical document for the Wimperis Accelerometer, detailing prices, users, operational principles, and a user testimonial.
| Identifier | ExFiles\Box 113\2\ scan0020 | |
| Date | 14th November 1922 guessed | |
| 12 WIMPERIS ACCELEROMETER PRICES Recording Accelerometer ... £ s. d.{John DeLooze - Company Secretary} 52. 0. 0. Paper ... per doz. rolls Ink ... per bottle Spare Pens ... each Indicating Accelerometer ... 9. 9. 0. Leather Case ... 12. 6. SOME USERS OF WIMPERIS ACCELEROMETERS GOVERNMENT DEPARTMENTS Admiralty Army Aircraft Factory Ceylon Government Crown Agents for the Colonies General Post Office London County Council New South Wales Government Nigerian Government Portsmouth Dockyard Swiss Government Uganda Government Union of S. Africa War Office RAILWAYS Buenos Aires & Pacific Railway Chemin de Fer du Midi Great Eastern Railway Great Western Railway Imperial Japanese Railways Lancashire & Yorkshire Rly. London Electric Railways London & North-Western Rly. London & South-Western Rly. Metropolitan Railway Midland Railway Nigerian Railways South African Railways MOTOR CAR MANUFACTURERS Adams Manufacturing Co. Albion Motor Car Co. Armstrong, Whitworth & Co. Austin Motor Car Co. Barford & Perkins Calthorpe Cars Crossley Motors Drewry Car Co. Itala Cars Lacre Motor Car Co. Leyland Motor Car Co. Milnes-Daimler-Mercedes Napier Motors Tilling-Stevens Thornycroft & Son Thomas Transmission White & Poppe Wolseley Tool & Motor Car Co. EXTRACT FROM LETTER FROM MESSRS. WHITE & POPPE, COVENTRY, MAKERS OF THE WHITE & POPPE ENGINES "WIMPERIS ACCELEROMETER.—As far as we can say, it is the only instrument that can be bought at a reasonable price with which the rolling resistance can be measured. It is very useful for us to be able to measure the rolling resistance of a car instead of guessing it. On several occasions, before we had this instrument, we had to take the engine and carburettor out of the car and put it on the test stand to see if the power was in the engine. Since using this instrument, half of such cases have disappeared. We have a piece of good road, very little influenced by the wet, on which we run cars from 15 to 20 m.p.h., and a good car usually shows about 60 lbs. per ton rolling resistance. We have had cars which customers complained would not pull, and have found by your instrument a rolling resistance of up to 120 lbs. per ton, so that the car was asking for twice the power necessary, and we had to find the reason for this heavy rolling resistance before touching the engine or carburettor. The instrument has been very useful to us in finding the difference between the rolling resistance on wet, dirty roads and dry roads, and by its aid we have been able to prove to our customers the difference in power asked for by wet, dirty roads and dry roads. It has surprised us how little is known about it. With the help of our “K” table, we have been able to calculate the petrol consumption within one or two miles of the real performance on the road." ELLIOTT BROTHERS, (LONDON) LIMITED. Established 1800. CENTRAL BUILDINGS, WESTMINSTER, LONDON, S.W., AND CENTURY WORKS, LEWISHAM, LONDON, S.E. WIMPERIS ACCELEROMETER 5 THE WIMPERIS ACCELEROMETER AND EQUILIBRISTAT A description of the indicating form of the Wimperis Accelerometer and of some measurements made with it was presented at the Sheffield meeting of the British Association and printed in The Engineer of September 16th, 1910. And a similar account of the Recording form of the instrument was published two years later by the Institution of Civil Engineers (Proc. I.C.E., Vol. 188). The Recording instrument is of especial use in railway work, where the permanent form of its indications is convenient. The charts it gives are of two kinds— (1) Those showing starting acceleration, braking and coasting ; enabling the tractive effort to be measured at all speeds ; and (2) Those showing the nature of the lay-out of the line ; the extent to which centrifugal force when rounding each and any curve is balanced by the super-elevation of the outer rail ; the safe speeds for negotiating the curves ; and the effectiveness of the transition curves. The Recording instrument is illustrated on page 3. The portion below the paper rolls is the usual clockwork mechanism for winding the paper along at a uniform rate, whilst the portion on the extreme left is the acceleration mechanism, which is arranged to read up to 8 ft. or 12 ft. per second per second. The latter mechanism is essentially identical with that of the direct-reading instrument shown on page 10, and diagrammatically in Fig. 2. [DIAGRAM OF ACCELEROMETER MECHANISM] LEG MAGNET HOLE IN DISC D K.SPUR WHEEL DISC CASE DIRECTION OF MOTION LEG ADJUSTABLE LEG FIG. 2. ELLIOTT BROTHERS, (LONDON) LIMITED. Established 1800. CENTRAL BUILDINGS, WESTMINSTER, LONDON, S.W., AND CENTURY WORKS, LEWISHAM, LONDON, S.E. | ||