| 摘要 |
An ignition system is described for an engine having four cylinder (51 to 54). Cylinders (52, 53, 54) lag cylinder (51) by 180 DEG , 90 DEG and 270 DEG of camshaft rotation. Each cylinder has a pair of spark plugs (55, 56). The system includes a pair of primary windings (60, 61) coupled respectively to a first and second pair of secondary windings (62 to 65). Winding (62) is connected to plugs (55) in cylinders (51, 52) and winding (63) is connected to plugs (56) in cylinders (51, 52) Windings (64, 65) are connected to the plugs in cylinders (53, 54) in a similar manner. Windings (60, 61) are connected to a power supply (70) through switches (73, 74) operated by a control unit (75) so as to produce sparks in each cylinder at appropriate instants during compression strokes. When, for example, sparks are produced in cylinder (51) during a compression stroke, sparks will also be produced in cylinder (52) which will be executing an exhaust stroke. Because of the lower pressure associated with an exhaust stroke, the voltage required in windings (62, 63) is less than twice that required to produce the spark in cylinder (51). |
