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).
Confidential letter to Messrs. Borg & Beck, Ltd. regarding the design and dimensional constraints of a 16' twin disc clutch for a tank project.
| Identifier | ExFiles\Box 130\3\ scan0146 | |
| Date | 20th December 1940 | |
| CONFIDENTIAL. 1110 20th December, 1940. Rm{William Robotham - Chief Engineer}/GB.4/CT. A.M. SHINKINS, Esq., Messrs. Borg & Beck, Ltd., Tachbrook Road, LEAMINGTON SPA, Warwickshire. Dear Sir, We are finding that space is very restricted in our tank project, and so we have made a drawing of a 16" twin disc clutch embodying dimensions which we hope will not be exceeded in your drawing. We enclose a print of our drawing (RL.463). The difference between the overall diameter and the spinner diameter is the same as on your 14" twin disc clutch. This gives an overall diameter of 19" which is the largest we can accommodate without cutting holes in the tank floor and increasing other centres. We sincerely trust that you will be able to keep down to this dimension. The dotted line (marked by red arrow) over the pressure plate spring cover shows the limit to which these covers can be extended if more space for the springs is required. We would like some idea of the loads falling on the two ball bearings which support the hub on which the clutch discs slide. The only condition under which these bearings can have more than the hub and disc weight is when the nip of the pressure plate is uneven when taking up the drive. We would like to know the probable magnitude of the bearing loads produced in this way. Yours faithfully, | ||