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 Messrs. Joseph Lucas Ltd. reporting a failure of an LR.7 regulator unit during testing.
Identifier | ExFiles\Box 166\2\ img198 | |
Date | 14th April 1938 | |
6092 - Rm{William Robotham - Chief Engineer}/RC.{R. Childs}10/JH. 14th April. 1938. Messrs. Joseph Lucas Ltd., Great King Street, Birmingham. For the attention of Mr. Toulmin. Dear Sirs, We regret to report a failure of one of the two LR.{Mr Ellor}7 regulator units mounted on R.R. bases which we recently received from you for test. The unit in question was as received connected up on the bench for test. At this point it was noticed that one of the low springs supporting the contact point on the cutout was bent in such a manner as to hold the two contacts together. This was rectified and the test commenced. It was then found that running both on open circuit and on load the regulator operated satisfactorily up to a certain point only. At speeds before this point the armature of the regulator got into a low frequency vibration with corresponding oscillations of the volt-meter and ammeter needles. This was accompanied by a loud metallic noise as the armature clicked back-wards and forwards between the pole face and the contact points. Finally in the case of the open circuit running, the armature remained in contact with the pole, while the voltage measured at terminals D and E fell to about 10 volts. We are returning under separate cover, this unit to you without tampering with it in any way; apart from what was done to the cutout contact spring. Perhaps you will let us have your comments after you have examined and tried it. To us it appears that the armature travels so near to the pole face that the springs are unable to control it. Yours faithfully, FOR ROLLS-ROYCE LTD. | ||