Ignition distributor-breaker system having centrifugal timing adjustment

Ignition distributor-breaker system for the timing of an ignition event in internal combustion engines, with centrifugal timing adjustment having

• a shaft (10) driven by the crankshaft of the engine;
• a support plate (11) driven by the shaft;
• a timing cam (14) concentric with the shaft and rotatable with the plate (11) and hence with the shaft while being additionally rotatable with respect to the plate (11) and hence the shaft (10);
• bias means (17) resiliently biassing the timing cam to rotate in a direction tending to retard the spark;
• centrifugal timing means (18, 21) secured to the plate (11) and engaging the timing cam (14) to adjust its relative rotary position with respect to the plate (11) to effect spark advance or retard upon relative change of rotary position of the cam with respect to the shaft when the cam is engaged by ignition breaker contacts;
• and limit means (13) limiting excursion of the timing means (18, 21) under influence of centrifugal force
• characterized in that
• the centrifugal timing means comprises two link elements (18, 21), one (18) of which engages the timing cam (14);
• and a knee joint (22, 26) and spring means (24) connecting said link elements (18, 21), said link elements forming a single centrifugally deflectable unit below a critical speed, the centrifugal force above said critical speed overcoming the connecting force of said spring means and permitting the other (21) of said link elements to deflect about the limit means (13) and thus break the deflecting unity of the link elements (18, 21) and permit rotation of the said one link element (18) with respect to the other (21) and consequently rotation of the timing cam (14) in the direction of spark retardation under the influence of the bias means (17).