Patent ID: 8408838
Filing Date: 2013-04-02
Classification: E01C

Abstract:
1. A milling machine comprising: a main frame; a rotatable cutter drum coupled with the frame; an engine mounted to the frame and operatively connected with the drum; a regulator configured to adjust a speed of the cutter drum; a speed selector configured to generate an input corresponding to a desired drum cutting speed; and a control configured to receive the input from the selector and to operate the regulator such that the drum speed at least generally corresponds to the desired speed; further comprising: at least one crawler assembly including a hydraulic motor; a pump configured to drive the crawler motor and being adjustable to vary a speed of the crawler motor; and a sensor configured to sense a speed of the drum and to communicate with the control; wherein the control is configured to compare sensed drum speed with the desired drum speed and to adjust the pump to reduce the speed of the crawler motor when the sensed drum speed has a value less than a predetermined portion of the desired drum speed, the predetermined portion of the desired drum speed being less than the desired drum speed; further comprising a travel speed input device configured to generate a travel speed input corresponding to a desired travel speed of the vehicle, the control being configured to receive the travel speed input, to adjust the pump such that the speed of the crawler motor generally corresponds to the desired travel speed when the drum speed is greater than the predetermined drum speed portion, and to alternatively adjust the pump to reduce the speed of the crawler motor when the sensed drum speed has a value less than the predetermined speed portion.