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 The British Thermostat Co. Ltd. discussing thermostat design and the lack of an adjustment feature.
| Identifier | ExFiles\Box 156\1\ scan0098 | |
| Date | 20th May 1935 | |
| X1328 Telephone: SUNBURY 456 (4 LINES). Codes: BENTLEY'S, WESTERN UNION. Telegrams & Cables: THERMOSTAT, SUNBURY COMMON. [Logo: FBI THE FEDERATION OF BRITISH INDUSTRIES INCORPORATED BY ROYAL CHARTER] THE BRITISH THERMOSTAT CO., LTD. Makers of Scientific Instruments. [Logo: MEMBERS OF THE NATIONAL UNION OF MANUFACTURERS NUM] TEDDINGTON WORKS. Windmill Road, Sunbury, Middlesex. DIRECTORS: M. {Mr Moon / Mr Moore} PAYNE. W. A. {Mr Adams} PAYNE. J. {Mr Johnson W.M.} E. {Mr Elliott - Chief Engineer} SHERLOCK. L. S. SWINNERTON-DYER. W.M.H/GN: Your Ref: Hs {Lord Ernest Hives - Chair} /Std.1/KW: May 20th, 1935. [Signature] STEADMAN Messrs. Rolls-Royce Limited, DERBY. Dear Sirs, We thank you for your letter of the 17th May. We will deal with your points in turn - (1). The remarks contained in our letter dated May 16th, relative to the bad feature in your design, namely that no adjustment is provided, referred to your thermostats E.86612 and EB. 667. If in the case of these units, you are agreeable to incorporate an adjustment, we withdraw our remarks, but we would point out that your latest order for these units incorporates no such adjustment. It is possible, of course, that it is your intention to provide some adjustment in the rest of your mechanism, but we would point out that the whole object of providing an adjustment is to enable the operator to set the valve head in such a position relative to the top plate of the bellows, that opening takes place at the required temperature. To do this, it is obvious that the bellows must have a greater total movement than the minimum lift of valve head required, and this feature we cannot see is incorporated in your design. | ||