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).
Letter from Ferodo discussing brake servo motor test results, including torque and temperature, and arranging to examine clutch discs.
| Identifier | ExFiles\Box 141\3\ scan0205 | |
| Date | 25th August 1933 | |
| x719. All Communications to be addressed to the Company. FERODO LIMITED BRAKE & CLUTCH LININGS CHAPEL-EN-LE-FRITH, VIA STOCKPORT, ENGLAND. TELEPHONE: 19 CHAPEL-EN-LE-FRITH (4 LINES) TELEGRAMS: FRICTION, PHONE, CHAPEL-EN-LE-FRITH. CODES: WESTERN UNION FIVE LETTER EDITION, BENTLEY'S COMPLETE & 2ND PHRASE, MARCONI INTERNATIONAL, LIEBER'S CODE, LIEBERS LATEST CODE, A.B.C. 5TH & 6TH EDITIONS. Depots:- LONDON 222, TOTTENHAM COURT RD W.1. ABERDEEN 26, GUILD STREET. BELFAST 8, 10 & 12, MONTGOMERY ST BIRMINGHAM 202, CORPORATION ST BRIGHTON 84, QUEEN'S ROAD. BRISTOL 19, PARK STREET. CARDIFF 39, CHARLES ST DUBLIN 120, UPPER ABBEY ST GLASGOW 70, WATERLOO ST LEEDS 25, HUNSLET RD LIVERPOOL 1-3, BERRY STREET. MANCHESTER 32, CATHEDRAL ST NEWCASTLE-ON-TYNE WORSWICK CHAMBERS, 10, WORSWICK ST OFF PILGRIM ST August 25th 1933 YOUR REF. Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls}3/MA OUR REF. FJF/WAC. Messrs. Rolls-Royce Ltd., DERBY. Dear Sirs, We thank you for your letter of the 22nd instant and may say at once that we shall welcome your assistance in the matter of the test of your brake servo motor - so, if convenient, perhaps your representative will call here on Monday morning or on any other day that suits you. We have already run a number of trials with different linings taking brake torque readings from an arm fixed to the outside plate of the servo. So far the force erected at the friction surface is 667 lbs, which corresponds to 1350 lbs-ins torque, pressure on linings 1100 lbs hence μ=0.3. According to our calculations 1350 lbs-ins torque will produce 937 lbs divided between the brake rod operating levers. The outstanding feature of the trials was the high temperature generated after a few seconds' engagement of the servo motor. Referring to the clutch discs mentioned in your letter, when these come to hand we will examine them and will advise you of our findings. Yours faithfully, FERODO LIMITED CHIEF ENGINEER. | ||