| 摘要 |
PURPOSE:To maintain the operation of an enging within a set number of revolutions for sure by controlling the switching of ignition synchronously with an ignition timing signal and setting the thermal characteristic of the clamp number of revolutions to be flat for taking a construction to check the number of revolutions at every ignition. CONSTITUTION:Whether the number of revolutions of an engine is clamped or not is controlled by the opening and closing of a switch SW1. A saw-tooth generating circuit 1 to determine the range of the clamp number of revolutions on the basis of values of a resistance R1 and a condenser C1 and voltage setting circuits 4 and 5 to set the uppermost limit voltage VH and the lowest limit voltage VL of the output of the said circuit 1 are provided. Meanwhile, a decision circuit 7 to decide whether the detected number of revolutions is lower or higher than the set one at every ignition timing signal on the basis of the comparison between outputs of two circuits 1 and 5, a gate circuit 8 to pass the input of an ignition signal on the basis of the decision signal for igniting an engine, and others are provided. When the decision circuit 7 decides that the detected number of revolutions is higher than the set one, the passage of the input of the ignition signal is checked by the gate circuit 8. |
