Patent ID: 7370458
Filing Date: 2008-05-13
Classification: A01D,Y02P

Abstract:
1. A speed control system, comprising: a lawnmower; an internal combustion engine mounted on said lawnmower; an actuator moving a throttle valve installed at an air intake passage of the engine; a controller controlling operation of the actuator such that the engine speed becomes equal to a predefined desired engine speed; a determiner determining whether the lawnmower is under a mowing operation based on a value indicative of a load of the engine; and a desired engine speed changer changing the desired engine speed based on a result of determination, wherein the determiner includes: a throttle opening detector detecting a degree of opening of the throttle valve; and an operating rate calculator calculating an operating rate of the engine as the value indicative of the load of the engine, based on the detected degree of opening of the throttle valve and the desired engine speed; and determines that the lawnmower is under a moving operation when the calculated operating rate is equal to or greater than a predetermined value.