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).
Methods for filling ignition coils, comparing liquid insulators with wax and proposing a new process for handling Seekay wax.
| Identifier | ExFiles\Box 61\1\ scan0295 | |
| Date | 23th April 1936 | |
| r6110 Hs{Lord Ernest Hives - Chair}/Wst. c. Hs.{Lord Ernest Hives - Chair} By.{R.W. Bailey - Chief Engineer} Sft{Mr Swift}/Mr Brock. By/RD. EJJ. E.3/HP.23.4.36. Exclusion of Air in Ignition Coils. Replying to your memo Hs{Lord Ernest Hives - Chair}/Wst.6/MJ.22.4.36, I see no harm in trying an experiment filling in the ignition coil with transformer oil, but I am personally against a liquid insulator which can leak out of a coil case when the latter is laid on its side on the bench, or inadvertently inverted. I note what you say about sealing up the top of the coil, but do not these liquid filled containers have to be ventilated, also one does not like to depend upon seals, even if it is permissible to shut the space in. We are committed for the present on the Exe engine to using an ignition coil in an inverted position, and I do feel that for general work it is desirable to persevere with a view to finding an insulator which has a higher melting point than paraffin wax. It appears to me that it would be possible to devise a scheme of a simple nature which might largely overcome the practical difficulties of handling and using Seekay wax. My proposal is to granulate the wax and place the requisite amount in a subdivided container fixed above each coil to be impregnated. The containers and coils complete could then be put in a vacuum pan and raised to a sufficient heat to drive out all moisture. After this the vacuum could be applied for withdrawing the air and the temperature could then be raised to the second stage, when the wax in the containers would be melted, and run into the coil cases below. After cooling down the operation would be complete, and there would be no question of having to use pipes and cocks and pumps for handling liquid Seekay, also the fumes would be shut in all the time. It might be argued that this process sounds as if it would be somewhat lengthy, but my view is that considerable time would be saved by the method suggested for melting the wax. E.{Mr Elliott - Chief Engineer} | ||