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 to AC-Sphinx Sparking Plug Co. regarding noise issues with car heaters and requesting alternative motors for testing.
| Identifier | ExFiles\Box 137\2\ scan0163 | |
| Date | 6th October 1938 | |
| 1158 Experimental Dept. Rm{William Robotham - Chief Engineer}/Std.9/MH.{M. Huckerby} 6th. October 1938. AC-Sphinx Sparking Plug Co., Dunstable, BEDS. For the attention of Mr.Bennion Brown. Dear Sirs, Referring to our discussion re car heaters on Wednesday last, we have now carried our preliminary tests on the heaters left with us and these tests have been entirely concerned with the noise question. As the heater stands at the moment it is too noisy for our requirements and the noise complained of is both motor noise and fan noise. If the fan speed is reduced, however, by means of a rehostat, the noise is, of course, very much lessened, and we would like to try another motor which is (a) of the 1950 r.p.m. type if possible instead of the 2500 r.p.m. type which you are at present using, and (b) selected by you as representing a quiet motor. Could you please let us have such a motor for test, on receipt of same we will return one of the motors we already have. We are today sending you an order for the two heaters which you left as samples. We are just getting out a rough scheme for utilising your heater with the motor and fan isolated and will send you a print of it shortly - it will necessitate a motor with a | ||