GB1481206A - Centrifugal advance device for the ignition distributor of an internal combustion engine - Google Patents

Abstract

1481206 Shaft couplings DUCELLIER ET CIE 26 Nov 1974 [11 Dec 1973] 51104/74 Heading F2U [Also in Division F1] A centrifugal ignition advance device which advances the ignition as engine speed rises in a first, lower, range of engine speeds and retards the ignition as the engine speed rises in a second, higher, range of speeds comprises a distributer shaft 1 to which a plate 2 is fixed, a sleeve 7 rotatably mounted on shaft 1 and carrying a plate 6 on pins on which are pivoted an auxiliary pair of weights 10, 11 and a main pair 14, 15 the auxiliary pair 10, 11 carrying pins 12, 13 engaging arcuate slots in plate 2 and the main pair 14, 15 carrying pins 18, 19 engaging arcuate slots of a plate 16 fixed for rotation with the contact breaker cam 17, a spring 22 interconnecting plates 2 and 6, a spring 28 interconnecting the pin 18 of weight 14 and plate 16 and a spring 25 interconnecting plate 6 and plate 16. The masses of the weights 10, 11, 14 and 15 and the strengths of springs 22, 25 and 28 are such that above a first engine speed the ignition advances due to weights 14 and 15 pivoting to move pins 18 and 19 in slots 20 and 21, this rotating plate 16 relative to shaft 1. The ignition stops advancing at a higher engine speed and remains constant until the speed is sufficient to move weights 10 and 11, which moves pins 12 and 13 in slots 3 and 4 and so retards the ignition as engine speed continues to rise. Weight 15 may also have a spring such as spring 28, but of different elasticity, to give a different function of ignition advance on rise of engine speed in the lower range.