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).
Wiring issue with Lucas Wind Tone Horns and a proposed new scheme to ensure they sound loud in emergencies.
| Identifier | ExFiles\Box 59\3\ Scan355 | |
| Date | 17th October 1935 | |
| E.{Mr Elliott - Chief Engineer} From Hs{Lord Ernest Hives - Chair}/Wst. c. to By.{R.W. Bailey - Chief Engineer} c. to Ev.{Ivan Evernden - coachwork} c. to Mx.{John H Maddocks - Chief Proving Officer} c. to Cx.{Major Len W. Cox - Advertising Manager} 86066 Hs{Lord Ernest Hives - Chair}/Wst.5/MA.17.10.35. LUCAS WIND TONE HORNS. As you are aware the present arrangement of the wiring of these horns as sent out by Messrs.Lucas suffers from the disadvantage that when the button is squarely depressed as it generally is in a sudden emergency, the horns only sound soft. This is considered by the Experimental Dept., to be detrimental to the success of these horns fitted to high speed cars and might prove dangerous. As Messrs.Lucas did not appear to have any alternative we examined the scheme in our Laboratory and evolved a new scheme would enables the horn to always sound "Loud" in any position of the button except when it is definitely rocked over to the "Soft" position. It will also sound loud if the button is rocked over from the "Soft" position to the "Loud" position should the button not be released sufficiently to break the contacts in the "Soft" position. The scheme is shewn on the attached diagram and consists of an additional winding on the operating relay wound in series with the de-magnetizing winding on the relay which inserts the resistance for "Soft" sounding. We have approached Messrs. Lucas with the scheme and it is now being tried out in their Research Laboratories. Hs{Lord Ernest Hives - Chair}/Wst. | ||