Patent ID: 8880300

Claim:
An outdoor power equipment unit, which comprises: (a) a frame carrying a work implement for performing a ground or turf grooming or working operation, the frame also carrying a prime mover whose speed is set by an operator using an adjustable throttle; (b) a traction drive system driven by the prime mover for moving the frame over the ground at an adjustable ground speed that is established by an operator using an adjustable speed control; (c) an implement drive system driven by the prime mover for moving the work implement in a grooming or working operation; (d) a fan drive system driven by the prime mover for powering a cooling fan that cools one fluid in at least one cooling system carried on the frame; (e) a sensor for providing an indicator of prime mover load during the working operation being performed by the work implement; (f) a temperature sensor for providing a temperature reading of the fluid during the working operation being performed by the work implement; and (g) an electronic controller for receiving the prime mover load indicator and temperature inputs from the sensors and for regulating the ground speed of the frame when the prime mover load indicator input is greater than a predetermined percentage of prime mover full load, the electronic controller regulating the speed of the frame in the following manner: (i) automatically reducing an output speed of at least one variable speed member contained in the traction drive system to reduce the ground speed of the frame without requiring that the speed control setting established by the operator through the position of the speed control be manually changed by the operator; (ii) automatically shutting off the cooling fan for periods of time that the temperature input is below a predetermined first limit thereof but resuming operation of the cooling fan when the temperature input reaches or exceeds the first limit thereof; and (iii) and maintaining the automatically reducing and automatically shutting off actions until the prime mover load indicator input drops back below the predetermined percentage of prime mover full load.