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 Adamant Engineering Company discussing the feasibility and characteristics of manufacturing a special steering gear cam.
| Identifier | ExFiles\Box 28\2\ Scan184 | |
| Date | 20th May 1933 | |
| XU094- Telegrams: “ADAMANT, Phone, Luton.” CONTRACTORS TO H.M. ADMIRALTY, WAR OFFICE & AIR MINISTRY. Telephone: LUTON 1818 (2 Lines). ADAMANT ENGINEERING COMPANY, LIMITED (Incorporating J.{Mr Johnson W.M.} C. THREADGOLD & SONS. Established 1878.) Engineers and Founders. SPECIALISTS in the DESIGN and MANUFACTURE of HIGH PRECISION TOOLS, JIGS, FIXTURES, etc. SPECIAL MACHINES, SPECIAL MACHINE TOOLS, and ACCURATE PRODUCTION WORK. SOLE MANUFACTURERS and SALES AGENTS for the MARLES and MARLES-WELLER STEERING GEARS. Directors: S. CARLTON SMITH, A.M.I.MECH.E., M.I.P.E. ENGR. LT.-COMMANDER F.{Mr Friese} G.{Mr Griffiths - Chief Accountant / Mr Gnapp} MATRAVERS, R.N., M.A. (CANTAB), A.M.I.MECH.E., A.M.I.E.E., M.I.A.E., M.I.P.E. O.{Mr Oldham} CARLTON SMITH, M.A. (CANTAB), F.I.S.A., M.I.P.E., Secretary. ALFRED SLATTER, M.I.E.E. J.{Mr Johnson W.M.} W. HAZEL, F.I.S.A. Your Ref/Rm{William Robotham - Chief Engineer}/7/IT. Our Ref/FGM/AGS/CB. Head Offices, Works and Design Dept. : DALLOW ROAD, LUTON. 20th. May, 1933. Messrs. Rolls-Royce Ltd., DERBY. Dear Sirs, For the attention of Mr. Robotham. We thank you for your letter of the 18th instant, as also of your two blue prints Ex.11209 and Ex.11226. We have very carefully considered the position as set forth in your letter, and would confirm that the gear ratio in question on the "J" Gear we have suggested to you would appear to be very difficult. We can, of course, cut you a special Cam for this gear giving a ratio of 16 to 1 in the box, but if this were done the helix angle would come out at approximately 8°45 mins, and although we have never cut a Cam with such a low helix angle, we are of the opinion that such an angle would not give a satisfactory performance on the road, due to the fact that it would be practically irreversible. The cutting of a Cam of this special ratio, however, would not be a very expensive operation, and we should be quite prepared to submit you a "J" Gear with such a Cam for you to test. The alternative suggestion you make that we should give you a box capable of 38 1/2° drop arm movement, but in other respects similar to our "J" Gear, we are afraid would not be at all satisfactory, as the rockershaft and follower at such an excessive angle from the perpendicular would introduce highly detrimental characteristics in the gear, and on lock the gear would be very inefficient. - 1 - | ||