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).
Technical description and comparison of American Bosch and Westinghouse condensers for battery ignition systems.
| Identifier | ExFiles\Box 34\1\ Scan265 | |
| Date | 1st December 1918 | |
| X.2512 Extract from Cy1-G 18721. X.4275 - RE: AMERICAN BOSCH BATTERY IGNITION. X.2512. (4) Condenser. This is of the standard American battery ignition type. A sample of a Westing-house condenser similarly made was sent to Mr. Royce with my letter Cy2/G25521 re "Distributor and Contact Breaker". The Westinghouse Co. use paper impregnated with "Halowax" made by the Bondensite Co. This wax has a high melting point and dielectric strength. The Bosch Co. use a double thickness varnished paper, sample of which is attached. Double thickness is used for increased dielectric strength and decreased chances of faults. The two strips of double thickness paper and two strips of tinfoil are wound on an oval shuttle by hand. Each strip passes under a rubbing contact which removes dust from the strip. The winding handle is connected to a Veeder counter, and at every so many turns the operator inserts a small strip of tinfoil for making the connections. Three connections are thuse made at equal distances along each plate. When the condenser is wound, it is pressed between dies to the "kidney" shape and inserted in the metal box. The wax which flowed on 4-EX was the black insulating wax on the condenser connecting strip which runs from the condenser to the L.T. terminal on the contact breaker casing. This wax is now replaced by one having a melting point of 220°F.{Mr Friese} R.R.C. 2397 (1000) 12.18. H.M. 104-74-325 (R.485). | ||