| 摘要 |
PURPOSE:To reduce exhaust gas and improve fuel consumption by providing in a centrifugal system ignition timing control device for a motor-cycle a means which restrains abrupt increase of ignition advancing angle after the number of revolution of a weight support base exceeds a predetermined value and thereby approximates the change in said ignition advancing angle to a ideal one. CONSTITUTION:When the number of revolution of a weight support base 3 is raised to point b by the rise of that of an engine and a centrifugal weight 8 swings outward over a predetermined angle so that ignition advancing angle gets out of the ideal one, a pin 14 of an ignition timing indicating tube 7 reaches and engages the left end of a slot 15 and tension of a return spring 16 acts on the weight 8 through the indicating tube 7 so that the ignition advancing angle is kept constant as shown by the line IIIb until centrifugal force received by the weight 8 overcomes the sum of tensions of return springs 12, 16. When the number of revolution of the support base 3 rises to point c, the centrifugal force received by the weight 8 overcomes the sum of the tensions of the return springs 12, 16 so that the weight 8 starts again to swing outward to advance the ignition timing. However, since the sum of the tensions of the return springs 12, 16 acts on the weight 8, grade of the advance angle becomes gentle as shown by IIIc and approaches the ideal ignition advancing angle. |
