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 Harrison Radiator Division discussing fan blade pitch control, pressure cooling issues, and copper brazing of radiators.
| Identifier | ExFiles\Box 149a\3\ scan0237 | |
| Date | 7th February 1939 | |
| HARRISON HARRISON RADIATOR DIVISION GENERAL MOTORS CORPORATION LOCKPORT NEW YORK February 7, 1939 Ed.{J. L. Edwards} Rolls-Royce Limited Derby, Derbyshire England Attention: Mr. C. S. Steadman Dear Mr. Steadman: Have been attempting since receipt of your letter of November 17 to get copies of patents which have been issued in the past showing ways and means for controlling fan blade pitch by the use of a thermostatic element in the jacket water. This type of control is used in conjunction with a water pump bolted to the front of the cylinder block. We have no drawings available for the variable pitch fan which we made here, and to date nothing further has been done other than preliminary tests. The internal friction was found to be very high and due to pressure of other work we have not had an opportunity to take this matter up again. Regarding the pressure cooling and the valve difficulty which you speak of, we too ran into the same trouble over here. It was corrected to a great extent, however, by the use of an auxiliary tank on the dashboard, this tank being mounted as high as possible and the overflow pipe from the radiator proper being connected to this tank. The pressure valve was fitted in the top of this auxiliary tank with an overflow pipe from the atmospheric side being so located as to discharge water underneath the car. The radiator was filled in the usual manner through the filler cap on the radiator proper. By moving the position of the valve from the radiator to the auxiliary tank, the valve was taken away from an area in which the water was in rapid circulation. In the new position at the top of the auxiliary tank there is no active agitation of the water and to some extent the tank itself acts as a precipitating device. We have not found it necessary to provide means for reducing or relieving the vacuum when the engine cools down. The copper brazing of radiators was discussed with your Doctor Smith upon the occasion of his recent visit here, and would like to take this opportunity to say that as far as we have gone, this project does not appear to be available for production for a few years. RADIATORS . HEAT EXCHANGERS . OIL TEMPERATURE REGULATORS . THERMOSTATS . HEATERS | ||