In-crop weed clipping implement

Abstract

An implement for clipping weeds in a field, where the weeds are standing taller than the crop. The implement comprises a plurality of rotatable blades on a frame, with variable height adjustment means to elevate the frame and position the blades above the crop but at a level sufficient to clip the upper portions of the weeds, The blades are powered by PTO-driven shaft segments, the segments connected by U-joints, wherein the implement further comprises alignment means for aligning the U-joints so that the frame can be folded for transport without damaging the shafts or U-joints.

1 . An agricultural implement for clipping weeds in a field containing a crop, the crop having an average crop height, the implement comprising:
 a frame;   a plurality of rotatable blades mounted on the frame for clipping the weeds;   drive means for rotating the plurality of rotatable blades; and   a plurality of wheels connected to the frame by variable height adjustment means, the wheels for use in moving the implement in the field;   the variable height adjustment means configured to selectively raise or lower the frame relative to the plurality of wheels to position the plurality of rotatable blades at a height sufficient to clip the weeds above the average crop height.   
     
     
         2 . The implement of  claim 1  wherein each of the plurality of rotatable blades is a mower blade depending beneath the frame. 
     
     
         3 . The implement of  claim 1  wherein the drive means comprise a power take-off output from a tractor, the tractor used to pull the implement through the field. 
     
     
         4 . The implement of  claim 1  wherein the drive means comprise at least one gearbox, the at least one gearbox connected to at least one of the plurality of rotatable blades by means of a belt, such that actuation of the gearbox causes the belt to rotate the at least one of the plurality of rotatable blades for clipping the weeds. 
     
     
         5 . The implement of  claim 1  wherein the front wheels are castor wheels. 
     
     
         6 . The implement of  claim 1  wherein the frame comprises a series of laterally aligned frame members, each of the frame members hingedly connected to adjacent frame members. 
     
     
         7 . The implement of  claim 6  further comprising at least one power cylinder connecting adjacent frame members and operable to rotate the adjacent frame members relative to each other. 
     
     
         8 . The implement of  claim 6  wherein:
 the frame comprises a central frame member; and 
 the drive means comprise a primary gearbox situated on the central frame member and a secondary gearbox situated on each of the frame members immediately adjacent the central frame member; 
 the primary gearbox is operably connected to each secondary gearbox by a respective shaft to actuate each secondary gearbox; and 
 each secondary gearbox is connected by means of a belt to the at least one rotatable blade mounted on the respective frame member, such that actuation of the secondary gearbox causes the belt to rotate the at least one rotatable blade for clipping the weeds. 
 
     
     
         9 . The implement of  claim 6  wherein:
 the frame comprises a central frame member; and 
 the drive means comprise a primary gearbox situated on the central frame member and a secondary gearbox situated on each of the frame members immediately adjacent the central frame member; 
 the primary gearbox is operably connected to each secondary gearbox to actuate each secondary gearbox by a respective inner shaft and outer shaft, the inner and outer shafts connected by a universal joint at a hinge line between the central frame member and each of the adjacent frame members; 
 each secondary gearbox is connected by means of a belt to the at least one rotatable blade mounted on the respective frame member, such that actuation of the secondary gearbox causes the belt to rotate the at least one rotatable blade for clipping the weeds; and 
 each of the universal joints is timed to allow rotation of the adjacent frame members relative to each other. 
 
     
     
         10 . The implement of  claim 6  wherein:
 the frame comprises a central frame member, a lateral frame member on each side of the central frame member, and a peripheral frame member on a side of each lateral frame member opposite to the central frame member; and 
 the drive means comprise a primary gearbox situated on the central frame member and a secondary gearbox situated on each of the lateral frame members and the peripheral frame members; 
 the primary gearbox is operably connected by a shaft to each secondary gearbox on the lateral frame members to actuate each secondary gearbox on the lateral frame members; 
 each secondary gearbox on the lateral frame members is operably connected by a shaft to the secondary gearbox on the adjacent peripheral frame member to actuate each secondary gearbox on the peripheral frame members; 
 each shaft comprises an inner shaft and an outer shaft, the inner and outer shafts connected by a universal joint at a hinge line between adjacent frame members; and 
 each of the universal joints is timed to allow rotation of the adjacent frame members relative to each other. 
 
     
     
         11 . The implement of  claim 1  wherein the variable height adjustment means comprise power cylinders for selectively rotating the wheels away from or toward the frame to respectively raise or lower the frame relative to the wheels to position the plurality of rotatable blades at a height sufficient to clip the weeds above the average crop height. 
     
     
         12 . The implement of  claim 11  further comprising a pivot framework to maintain the frame generally parallel to the ground at a selected height. 
     
     
         13 . The implement of  claim 2  further comprising a plurality of generally vertical tines spaced along either or both of a leading edge and a trailing edge of the frame, the tines extending downwardly from the frame to a level lower than the mower blades. 
     
     
         14 - 29 . (canceled) 
     
     
         30 . A method for weed control in a standing crop, the method comprising the steps of:
 a. providing a movable frame comprising:
 a plurality of cutting members configured for clipping weeds; and 
 a plurality of ground-engaging wheels having an adjustable distance from the frame; 
   b. determining an average crop height level and an average weed height level for the standing crop;   c. where the average weed height level is greater than the average crop height level, adjusting the distance between the wheels and the frame such that the cutting members are at a height between the average crop height level and the average weed height level;   d. actuating the cutting members; and   e. moving the frame through the standing crop, allowing the cutting members to cut off tops of the weeds.   
     
     
         31 . The method of  claim 30  wherein the method comprises repeating steps b. through e. at a plurality of times throughout a growing season of the standing crop. 
     
     
         32 . The method of  claim 30  wherein the movable frame is pulled by a tractor through the standing crop and a power take-off of the tractor is used to drive the cutting members. 
     
     
         33 . The method of  claim 32  wherein actuating the cutting members comprises:
 providing at least one gearbox on the frame, the gearbox connected to the power take-off by means of a shaft; and 
 connecting the gearbox by a belt to the cutting members; 
 such that actuation of the gearbox by the power take-off causes the belt to rotate the cutting members to cut off the tops of the weeds. 
 
     
     
         34 . The method of  claim 30  wherein the frame comprises a central frame member and a lateral frame member, the central frame member and the lateral frame member hingedly connected for relative rotation, the method comprising the further steps after step e. of:
 rotating the lateral frame member upwardly and out of horizontal; and 
 transporting the frame away from the standing crop. 
 
     
     
         35 . The method of  claim 30  wherein the frame comprises a central frame member and two lateral frame members hingedly connected to opposite sides of the central frame member for relative rotation, the method comprising the further steps after step e. of:
 rotating the lateral frame members upwardly and out of horizontal; and 
 transporting the frame away from the standing crop. 
 
     
     
         36 . The method of  claim 30  wherein adjusting the distance between the wheels and the frame is achieved by using power cylinders to rotate the wheels toward or away from the frame. 
     
     
         37 . The method of  claim 30  further comprising the step of maintaining the frame generally parallel to the ground during the step of adjusting the distance between the wheels and the frame. 
     
     
         38 . A method for in-crop weed clipping comprising the steps of:
 a. providing a movable frame comprising:
 a plurality of cutting members; and 
 a plurality of ground-engaging wheels having an adjustable distance from the frame; 
   b. determining an average crop height level and an average weed height level for a field containing both a crop and weeds;   c. where the average weed height level is greater than the average crop height level, adjusting the distance between the wheels and the frame such that the cutting members are at a height between the average crop height level and the average weed height level;   d. actuating the cutting members; and   e. moving the frame through the field, allowing the cutting members to cut off tops of the weeds.   
     
     
         39 . The method of  claim 38  wherein the method comprises repeating steps b. through e. at a plurality of times throughout a growing season of the crop. 
     
     
         40 . The method of  claim 38  wherein the movable frame is pulled by a tractor through the crop and a power take-off of the tractor is used to drive the cutting members. 
     
     
         41 . The method of  claim 40  wherein actuating the cutting members comprises:
 providing at least one gearbox on the frame, the gearbox connected to the power take-off by means of a shaft; and 
 connecting the gearbox by a belt to the cutting members; 
 such that actuation of the gearbox by the power take-off causes the belt to rotate the cutting members to cut off the tops of the weeds. 
 
     
     
         42 . The method of  claim 38  wherein the frame comprises a central frame member and a lateral frame member, the central frame member and the lateral frame member hingedly connected for relative rotation, the method comprising the further steps after step e. of:
 rotating the lateral frame member upwardly and out of horizontal; and 
 transporting the frame away from the crop. 
 
     
     
         43 . The method of  claim 38  wherein the frame comprises a central frame member and two lateral frame members hingedly connected to opposite sides of the central frame member for relative rotation, the method comprising the further steps after step e. of:
 rotating the lateral frame members upwardly and out of horizontal; and 
 transporting the frame away from the crop. 
 
     
     
         44 . The method of  claim 38  wherein adjusting the distance between the wheels and the frame is achieved by using power cylinders to rotate the wheels toward or away from the frame. 
     
     
         45 . The method of  claim 38  further comprising the step of maintaining the frame generally parallel to the ground during the step of adjusting the distance between the wheels and the frame. 
     
     
         46 - 51 . (canceled)