Automatic Rotor Speed Control

Abstract

A movable machine includes an engine, a rotatably-mounted rotor, a rotor driver mounted on a frame supported on a plurality of ground engaging members; a rotor speed sensor and machine ground speed sensor provide a rotor speed signal and machine ground speed signal, respectively, to a controller. The controller is configured to use a current machine conditions parameter to determine an optimal rotor speed and command the rotor drive to adjust the rotational speed of the rotor to the optimal speed. The current machine conditions parameter includes the rotor speed signal, the machine ground speed signal, and cutting depth.

We claim: 
     
         1 . A movable machine having a frame supported on a plurality of ground engaging members, the machine comprising:
 an engine;   a rotor rotatably mounted relative to the frame,   a rotor driver mounted on the frame and operatively connected to the rotor and the engine to provide rotational movement,   a rotor speed sensor disposed and adapted to provide a rotor speed signal indicative of a rotational speed of the rotor,   a machine ground speed sensor disposed and adapted to provide a machine ground speed signal indicative of a machine ground speed of the movable machine,   a controller configured to use a current machine conditions parameter to determine an optimal rotor speed, the current machine conditions parameter including the rotor speed signal, the machine ground speed signal, and a cutting depth of the rotor,   wherein the controller commands the rotor driver to adjust the rotational speed of the rotor to the optimal rotor speed.   
     
     
         2 . The movable machine of  claim 1  wherein the current machine conditions parameter includes at least one of a type of material to be cut and a cut pattern. 
     
     
         3 . The movable machine of  claim 1  wherein the rotor includes at least one cutting tool and the current machine conditions parameter further includes information indicative of the cutting tool. 
     
     
         4 . The movable machine of  claim 1  further including an operator control adapted to provide an operator control signal indicative of an operator rotor command to the controller, and the current machine conditions parameter further includes the operator control signal. 
     
     
         5 . The movable machine of  claim 3  further including at least one wear sensor disposed to sense cutting tool wear and adapted to provide a cutting tool wear signal to the controller, and the current machine conditions parameter further includes the cutting tool wear signal. 
     
     
         6 . The movable machine of  claim 1  further including at least one particle size sensor to sense cut particle size and to provide a cut particle size signal to the controller, and the current machine conditions parameter further includes the cut particle size signal. 
     
     
         7 . A method of controlling a rotational speed of a rotatably-mounted rotor in a movable machine, the method being implemented by a controller and comprising:
 determining current machine conditions including machine ground speed and type of material to be cut,   determining an optimal rotor speed based upon said current machine conditions,   comparing the optimal rotor speed to an actual rotor rotational speed to identify any difference between the actual rotor rotational speed and the optimal rotor speed, and   adjusting the actual rotor rotational speed toward the optimal rotor speed if an adjustment of the actual rotor rotational speed is indicated.   
     
     
         8 . The method of  claim 7  wherein the step of comparing includes comparing the difference to a preset threshold difference, and the step of adjusting includes adjusting the rotor speed when the difference is greater than the preset threshold difference. 
     
     
         9 . The method of  claim 7  wherein the step of determining current machine conditions includes sensing at least one of the following: machine ground speed, material type, cut particle size, machine height, cutting tool type, rotor wear. 
     
     
         10 . The method of  claim 7  further including providing at least one of a material type signal indicative of the type of material to be cut and a cut pattern signal indicative of a cut pattern to the controller. 
     
     
         11 . The method of  claim 7  wherein determining the current machine conditions includes determining cutting tool type, the method further including providing a cutting tool type signal indicative of the cutting tool type to the controller. 
     
     
         12 . The method of  claim 7  further including providing an operator control signal indicative of an operator rotor command to the controller. 
     
     
         13 . The method of  claim 7  wherein the step of determining current machine conditions includes at least one of determining at least one physical characteristic of the rotor, and determining a cutting depth of the rotor. 
     
     
         14 . The method of  claim 13  wherein determining at least one physical characteristic of the rotor includes programming at least one of an outer diameter of the rotor, a rotor type, a cutting tool configuration, a material from which the at least one cutting tool is formed, and cutting tool wear into the controller during set up. 
     
     
         15 . The method of  claim 7  wherein adjusting the rotor speed includes at least one of adjusting a speed of an engine operatively connected to the rotor, adjusting an operating gear of a gear train operatively connected to the rotor, and adjusting a hydraulic rotor drive motor operatively connected to the rotor. 
     
     
         16 . A machine comprising:
 a plurality of ground engaging members,   a frame movably supported on the plurality of ground engaging members,   a rotor rotatably coupled to the frame,   a rotor driver operatively connected to the rotor to provide rotational movement to the rotor,   a controller configured to:
 receive a current machine conditions parameter, the current machine conditions parameter comprising a ground speed of the machine, a rotational speed of the rotor, and a cutting depth of the rotor; 
 determine a target rotor speed based on the current machine conditions parameter; and 
 adjust the rotational speed of the rotor to the target rotor speed. 
   
     
     
         17 . The machine of  claim 16  further including:
 a rotor speed sensor disposed and adapted to provide a rotor speed signal indicative of the rotational speed of the rotor, 
 a ground speed sensor disposed and adapted to provide a ground speed signal indicative of the ground speed of the machine. 
 
     
     
         18 . The machine of  claim 17  wherein the rotor includes at least one cutting tool and the current machine conditions parameter further includes information indicative of a cutting tool type, the machine further including at least one of a cutting tool type sensor disposed to sense the cutting tool type and provide a cutting tool type signal, and an operator control adapted for entry of the cutting tool type and provision of an entered cutting tool type signal. 
     
     
         19 . The machine of  claim 18  further including an operator control adapted to provide an operator control signal indicative of an operator rotor command to the controller, and the current machine conditions parameter further includes the operator control signal. 
     
     
         20 . The machine of  claim 18  further including at least one wear sensor disposed to sense cutting tool wear and adapted to provide a cutting tool wear signal to the controller, and the current machine conditions parameter further includes the cutting tool wear signal.