| 摘要 |
PURPOSE:To obtain optimum ignition timing in the full load region by providing the third timing control means to cause relative difference to produce in the timing control amount in the high load region compared to at least low- and medium-load regions in an internal combustion engine provided with a centrifugal timing control means and a negative-pressure timing control means. CONSTITUTION:The distriburor shaft 1 and the cam shaft 3 are connected through the centrifugal timing control means 8, and the rotation phase of the cam shaft 3 is advanced by the opening of the governor weight 9 due to the rise of rotation number, whereby the ignition timing control of an ignition trigger signal generated from the trigger detector 19 of the pickup 24 related to the projection 18 of the cam 13 is made great. When the rotation number is in a high load region of approx. 4,800rpm, the breaker 10 is sent up according to suction negative pressure introduced into the bellows 11 of the third timing control means 7 by the pipe 15 and the detector 19 is risen. Since the projection 18 is so twisted that its response to the rise of the detector 19 is delayed, the degree of timing control can be increased. |
