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 of the Rotor, Cam, Condenser, and Advance Mechanism of an ignition system.
| Identifier | ExFiles\Box 37\1\ scan 107 | |
| Date | 25th May 1921 guessed | |
| Oy2 - G 25521 Sheet #2. (2) ROTOR: The rotor is a disc of molded Bakelite having a nickel conductor molded in it or fixed by screws in a recess in it (as in the Bosch). The hole in the distributor for the spindle is circular, with a flat one side, and is often finished by a drift after molding to insure a tight push fit on the spindle which is ground circular and flattened one side. This hole is generally not quite deep enough to satisfy one that the rotor will not wobble, but it can be made as deep as desired. The circular form of the rotor makes for balance and sheds off any moisture without allowing it to get on the points. (Like the American Bosch rotor) (3) THE CAM: The rotor spindle is hollow and advances around the center spindle, which is driven directly by the timing gears, the advance being effected by the automatic advance mechanism which is always used on American ignitions. Below the rotor and formed on the rotor spindle comes the cam, and around this is the chamber containing the contact breaker rocker and condenser. (4) CONDENSER: This is always enclosed in a sealed metal container and is made of two strips of tinfoil and two strips of thin paper, treated with "Halowax" - a special insulating wax made by the Condensite Co. The four strips are wound together on a circular spool and the roll is then squeezed into the desired shape and sweated into the metal condenser case. The Westinghouse Co. allows about 30 seconds for winding a condenser. Condensers made in a similar way are used by all American makers, and I have never heard of a case of trouble arising with them, though I have asked a number of persons who have used American cars daily for years. (A sample of a dismantled condenser made by the Westinghouse Co. is enclosed.) (5) ADVANCE MECHANISM: This is in the chamber below the contact breaker. The American Bosch advance is not considered as good as some of the others which use two centrifugal weights on vertical pivots, which move out horizontally and operate the advance by means of | ||