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).
Testing and approval of an over-running indicator in an A.T. rev-counter for fitment to a Bentley chassis.
| Identifier | ExFiles\Box 165\2\ img148 | |
| Date | 21th December 1937 | |
| To By.{R.W. Bailey - Chief Engineer} from Rm{William Robotham - Chief Engineer}/RC.{R. Childs} c. Sg.{Arthur F. Sidgreaves - MD} c. Hs.{Lord Ernest Hives - Chair} c. Da.{Bernard Day - Chassis Design} c. Mx.{John H Maddocks - Chief Proving Officer} c. Hd.{Mr Hayward/Mr Huddy} c. Sr. 6134 Rm{William Robotham - Chief Engineer}/RC.{R. Childs}1/MR.21.12.37. RE OVER-RUNNING INDICATOR INCORPORATED IN AN A.T. REV-COUNTER. The A.T. people have submitted for our test a rev-counter which will indicate when an engine has been over-revved. This device is in the form of a very light pointer which rests on a stop at the 4,500 mark. If this speed is exceeded, the pointer in its normal operation bears on this indicator and moves it to the maximum speed attained. It is agreed that this device is only for our use and should not be any more noticeable than is necessary. We have subjected this particular instrument to a bench test and find same quite satisfactory. The important points are:- (1) That the device is unobstrusive. (2) That it is not displaced by vibration or shocks, such as will be experienced in normal use. (3) That the resistance offered to the pointer is neglible. (4) That the accuracy of the instrument is not effected. With regard to (2) the instrument was subjected to 10 hours bench test running at an indicated speed of 3,500 followed by 4 hours, mounted on the dashboard of a chassis under-going bump tests. At the end of these tests no displacement of the device had taken place. We noticed, however, that this indicator could be displaced by a shock, such as obtained by thump-ing the side of the instrument with one's hand; however, it would be necessary to remove the instrument to displace the indicator in this way. In all other respects the device is quite satis-factory, and we feel that this type of instrument may be recomm-ended for fitment to the Bentley chassis without further test. Rm{William Robotham - Chief Engineer}/RC.{R. Childs} | ||