Work machine with automatic pitch control of implement

Abstract

A blade for a work machine includes a body having a main portion including a top edge, a bottom edge, a first lateral edge and a second lateral edge. A wing portion is pivotally coupled to the body about a pivot axis. The first lateral edge includes a curved edge extending outwardly towards the wing portion, where the curved edge forms an apex between the top edge and the bottom edge. A first axis is defined through a first intersection point and a second intersection point, the first intersection point located at an intersection of the top edge and the first lateral edge and the second intersection point located at an intersection of the bottom edge and the first lateral edge. A second axis is defined through the apex and is parallel to the first axis. The pivot axis is located between the first axis and the second axis.

1 . A method for automatically adjusting a pitch of a blade on a work machine, comprising:
 providing the blade with a main portion, a wing portion pivotally coupled to the main portion, a first actuator, a second actuator, at least one sensor, and a controller;   detecting with the sensor a position of the wing portion relative to the main portion;   determining by the controller if the wing portion is angled relative to the main portion based on an input from the sensor;   determining by the controller if the first actuator is operably angling the blade;   determining a desired pitch of the blade by the controller;   determining by the controller a position of the second actuator to achieve the desired pitch; and   adjusting by the controller the position of the second actuator.   
     
     
         2 . The method of  claim 1 , wherein the controller performs the adjusting step only if the controller determines the wing portion is angled relative to the main portion. 
     
     
         3 . The method of  claim 1 , wherein the controller performs the adjusting step only if the controller determines the first actuator is operably angling the blade. 
     
     
         4 . The method of  claim 1 , further comprising storing control logic inclusive of a kinematic model of the blade and a C-frame geometry in a memory unit of the controller. 
     
     
         5 . The method of  claim 1 , wherein the controller performs the adjusting step only if the controller determines the wing portion is angled relative to the main portion and the first actuator is operably angling the blade. 
     
     
         6 . The method of  claim 6 , wherein the desired pitch corresponds to a pitch of the blade at a time at which the blade is angled by the first actuator. 
     
     
         7 . The method of  claim 1 , wherein the controller evaluates a direction and magnitude of a command received by the controller for controlling the first actuator. 
     
     
         8 . The method of  claim 7 , further comprising calculating the desired pitch by the controller based on a function of kinematics of the blade and the direction and magnitude of the command. 
     
     
         9 . A method for automatically adjusting a pitch of a blade on a work machine, comprising:
 providing the blade with a main portion, a wing portion pivotally coupled to the main portion, a first actuator, a second actuator, and a controller including a memory unit;   determining by the controller if the wing portion is angled relative to the main portion;   determining by the controller if the first actuator is being actuated to change an angle of the blade;   if the wing portion is angled relative to the main portion and the first actuator is being actuated, determining a desired pitch of the blade by the controller;   determining by the controller a position of the second actuator to achieve the desired pitch; and   adjusting by the controller the position of the second actuator.   
     
     
         10 . The method of  claim 9 , wherein the position of the second actuator corresponds to a length of a cylinder. 
     
     
         11 . The method of  claim 9 , wherein the adjusting step comprises extending or retracting the second actuator until the pitch of the blade is at the desired pitch. 
     
     
         12 . The method of  claim 9 , wherein the controller continuously determines if the pitch of the blade is different from the desired pitch. 
     
     
         13 . The method of  claim 9 , further comprising detecting with a sensor a position of the wing portion relative to the main portion and communicating the position to the controller. 
     
     
         14 . The method of  claim 9 , wherein the controller performs the adjusting step only if the controller determines the wing portion is angled relative to the main portion and the first actuator is operably angling the blade. 
     
     
         15 . The method of  claim 9 , wherein the controller evaluates a direction and magnitude of a command received by the controller for controlling the first actuator. 
     
     
         16 . The method of  claim 15 , further comprising calculating the desired pitch by the controller based on a function of kinematics of the blade and the direction and magnitude of the command. 
     
     
         17 . A work machine, comprising:
 a chassis;   a cab mounted to the chassis;   a blade coupled to the chassis, the blade comprising at least a main portion and a wing portion, the wing portion being pivotally coupled to the main portion;   a first actuator coupled between the chassis and the blade, the first actuator being operably controlled to adjust an angle of the blade;   a second actuator coupled between the chassis and the blade, the second actuator being operably controlled to adjust a pitch of the blade;   a third actuator coupled between the chassis and the blade, the third actuator being operably controlled to adjust a tilt of the blade;   a controller disposed in communication with the first actuator, the second actuator, and the third actuator, the controller operably controlling each actuator based on user inputs and control logic stored in a memory unit of the controller; and   at least one sensor disposed in electrical communication with the controller, the at least one sensor detecting a position of each actuator or a position of the blade;   wherein, the controller executes the control logic to determine if the wing portion is angled relative to the main portion, determine if the first actuator is being actuated to change an angle of the blade, determine a desired pitch of the blade, and control the position of the second actuator until the pitch of the blade corresponds with the desired pitch.   
     
     
         18 . The work machine of  claim 17 , further comprising a fourth actuator coupled between the main portion and the wing portion of the blade, wherein the fourth actuator is operably controlled by the controller to control an angle of the wing portion relative to the main portion. 
     
     
         19 . The work machine of  claim 18 , further comprising:
 a first pocket defined between the main portion and the wing portion of the blade, the first pocket being free of any structure to allow free pivotal movement of the wing portion relative to the main portion; and   a second pocket defined on a backside of the main portion, the second pocket being free of any structure to allow movement of the fourth actuator between an extended position and a retracted position.   
     
     
         20 . The work machine of  claim 17 , wherein:
 the controller is configured to receive a command to actuate the first actuator for adjusting the angle of the blade, where the command comprises a direction component and a magnitude component;   the controller calculates the desired pitch based on a function of a kinematics of the blade, the direction component, and the magnitude component.