Patent ID: 7666117
Filing Date: 2010-02-23
Classification: A01D,F16D,Y10T

Abstract:
1. A power-transmission control mechanism for a lawn mower in which power of an internal combustion engine is transmitted to a mowing blade through an electromagnetic clutch, wherein; the power-transmission control mechanism comprises: an operating switch that is turned on or off by an operator; an engine rotational speed detector that detects engine rotational speed of the internal combustion engine; and an electromagnetic clutch controller that controls operation of the electromagnetic clutch on the basis of an operation signal of the operating switch and the engine rotational speed detected by the engine rotational speed detector; and wherein the electromagnetic clutch controller is configured to periodically repeats: reading the engine rotational speed detected by the engine rotational speed detector, during a predetermined time, when the operating switch is turned on, comparing a present engine rotational speed read in present cycle with a previous engine rotational speed read in a previous cycle, engaging the electromagnetic clutch when the present engine rotational speed is equal to or higher than the previous engine rotational speed, and disengaging the electromagnetic clutch when the present engine rotational speed is lower than the previous engine rotational speed.