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).
Inquiry to Croft Engineering Co. about a suitable variable speed pulley drive for two test rigs.
| Identifier | ExFiles\Box 119\1\ scan0210 | |
| Date | 19th June 1939 | |
| 1024 Experimental Dept. Rm{William Robotham - Chief Engineer}/AFM.{Anthony F. Martindale}8/MH.{M. Huckerby} 19th. June, 1939. Messrs. Croft Engineering Co., BRADFORD. Dear Sirs, Variable Speed Pulley Drive. We have two test rigs in the works which we wish to alter to a variable speed drive. Vauxhall Motors have one of these which they say they bought from you and on which they report favourably. Our motors are 40 H.P. motors running at 725 r.p.m. which is at present stepped down in two stages to 120 r.p.m. by rows of Vee belts (Tex rope). We believe the Vauxhall motor is only 20 H.P. We should be glad to know if you have a suitable gear for our job and what its cost would be. We would want the minimum speed to be 100 r.p.m. (instead of 120) and the maximum to be about 300 r.p.m. (or more if it is possible). It is seldom that we use the full 40 H.P. as the rig does the same work as the Vauxhall 20 H.P. rig. Yours faithfully, for ROLLS-ROYCE LTD. | ||