| 摘要 |
PURPOSE:To obtain an optimal ignition characteristic by making a switch-over, depending upon an engine parameter, between signals from angle sensors which have a constant advanced angle/constant fixed angle characteristics according to the change in the number of revolution. CONSTITUTION:An angle sensor output is switched-over by controlling a relay contact point 19 depending upon a engine parameter detected by a sensor 18. When said relay contact point 19 is off, this becomes a constant fixed angle shown by a characteristic (b) which is decided by a sensor 7a. When said relay contact point 19 is on, this becomes like a chracteristic (a) in the figure on the right which is decided by a sensor 7b. When relay contact point 19 is off, a transistor 13 is controlled only by said sensor 7a. When relay contact point 19 becomes on, owing to a self-hold characteristic of thyrister 10, said transistor 13 is controlled by said sensor 7b which has said characteristic (a) varying in relation to a change in the number of revolution. At a time when said transistor 13 becomes off, a thyrister 6 is fired via condenser 15 to ignite the engine. Hence, ignition angle can be controlled always optimally with this mechanism. |
