Height sensor arrangement for agricultural applications

An arrangement attached to an agricultural header assembly used in the harvesting of crops for controlling the height of said header assembly above the soil, said header assembly including a lower surface and cutting mechanism for cutting crops, said arrangement comprising:

• a rotation sensor attached to the header assembly forward of said cutting mechanism;
• a curved, flexible ground engaging arm having a first end attached to said rotation sensor and a second opposed free end extending rearwardly and disposed below and forward of said cutting mechanism, wherein variation in soil elevation causes deflection of said arm and displacement of said rotation sensor for providing a height control signal, and wherein as the height of the header assembly above the soil decreases, said arm engages the soil at an increasingly forward location along the length of said arm to allow for earlier detection of elevated soil as the height of the header assembly above the soil is reduced for avoidance of soil contact with the cutting mechanism, and wherein when said arm encounters elevated soil and is deflected, said arm contacts the lower surface of the header assembly and assumes a less curved configuration;
• and
• a height controller coupled to the header assembly and to said rotation sensor and responsive to said height control signal for raising the header assembly when said arm encounters elevated soil.

An arm for use in a rotation sensor mounted to an agricultural implement for engaging the ground and providing an indication of the height of the implement above the ground, wherein said agricultural implement includes a bottom panel, said arm comprising:

• a first variably curved, flexible, elongated elastomeric member having opposed proximal and distal ends, wherein said proximal end is coupled to said sensor and said distal end engages the ground;
• a second variably curved, flexible, elongated member comprised of a high strength material and coupled to and extending substantially between the proximal and distal ends of said first member, said second member having a proximal end coupled to said sensor;
• and
• a third variably curved high strength rigid member disposed adjacent to and coupled to the respective proximal portions of said first and second members, wherein all of the members have the same curvature and the curvature of the members allows a point of contact of said arm with the ground to move toward said sensor with a lowering of the height of the sensor above the ground, and wherein said arm contacts the bottom panel of the agricultural implement and assumes a less curved configuration when said arm engages an elevated portion of the around.

Apparatus for use in an agricultural implement having a skid panel for measuring the height of the skid panel of said agricultural implement above the soil as said agricultural implement traverses a field, said apparatus comprising:

• a shaft mounted to the agricultural implement;
• rotation sensing means coupled to said shaft and responsive to rotation of said shaft for providing an output signal representing rotational displacement of said shaft;
• and
• a curved flexible arm having a proximal end connected to said shaft and a distal end engaging the soil, wherein said arm is concave in an upward direction and rotates in a first direction when said arm contacts upraised soil and rotates in a second opposed direction when said arm contacts a depression in the soil, and wherein said arm is characterized as having increasing stiffness in proceeding from its distal end to its proximal end and wherein said arm assumes a less curved configuration and engages the skid panel of the agricultural implement when said arm contacts upraised soil.

Apparatus for use in an agricultural implement for measuring the height of said agricultural implement above the soil as said agricultural implement traverses a field, said apparatus comprising:

• a shaft mounted to the agricultural implement;
• rotation sensing means coupled to said shaft and responsive to rotation of said shaft for providing an output signal representing rotational displacement of said shaft;
• and
• a curved flexible arm having a proximal end connected to said shaft and a distal end engaging the soil, wherein said arm is concave in an upward direction and rotates in a first direction when said arm contacts upraised soil and rotates in a second opposed direction when said arm contacts a depression in the soil, and wherein a point of contact of said arm with the soil moves forward in a direction of travel of the implement toward the proximal end of said arm as the height of the implement above the soil is reduced to provide an increasingly early indication of contact with the soil of the implement as its height above the soil decreases;
• and
• biasing means coupled to said shaft for urging said shaft and arm in said second direction of rotation, wherein said biasing means applies a downward force on the distal end of said arm engaging the soil, and wherein said biasing means is adjustable for selecting the downward force on said arm over a range of downward forces.

For use on a header attached to a combine, said header including a crop engaging and gathering mechanism located in a forward, lower portion of said header for removing the crop from a field and providing the crop to the combine for processing therein, a sensor arrangement for maintaining the header a selected height above the ground comprising:

• a rotation sensor;
• a flexible curved arm having a proximal end coupled to said rotation sensor and an opposed distal end engaging the ground, wherein said arm rotates about its proximal end in a first direction when the distal end of said arm engages an upraised portion of ground and rotates in a second opposed direction when the distal end of said arm engages a depression in the ground;
• and
• mounting means for attaching said arm and rotation sensor to the header at a location forward of or adjacent to the header's crop engaging and gathering mechanism for preventing contact between the header and an upraised portion of the ground.

Apparatus for use in an agricultural implement for measuring the height of said agricultural implement above the soil as said agricultural implement traverses a field, said apparatus comprising:

• a shaft mounted to the agricultural implement;
• rotation sensing means coupled to said shaft and responsive to rotation of said shaft for providing an output signal representing rotational displacement of said shaft;
• and
• a curved flexible arm having a proximal end connected to said shaft and a distal end engaging the soil, wherein said arm is concave in an upward direction and rotates in a first direction when said arm contacts upraised soil and rotates in a second opposed direction when said arm contacts a depression in the soil, and wherein said arm is characterized as having increasing stiffness in proceeding from its distal end to its proximal end.

Apparatus for use in an agricultural implement for measuring the height of said agricultural implement above the soil as said agricultural implement traverses a field, said apparatus having a lower surface disposed above the soil, said apparatus comprising:

• a shaft mounted to the agricultural implement;
• rotation sensing means coupled to said shaft and responsive to rotation of said shaft for providing an output signal representing rotational displacement of said shaft;
• and
• a curved flexible arm having a proximal end connected to said shaft and a distal end engaging the soil, wherein said arm is concave in an upward direction and rotates in a first direction when said arm contacts upraised soil and rotates in a second opposed direction when said arm contacts a depression in the soil, and wherein a point of contact of said arm with the soil moves forward in a direction of travel of the implement toward the proximal end of said arm as the height of the implement above the soil is reduced to provide an increasingly early indication of contact with the soil of the implement as its height above the soil decreases, and wherein said arm engages the lower surface of the apparatus and assumes a less curved configuration when said arm contacts upraised soil.

An arm for use in a rotation sensor mounted to an agricultural implement for engaging the ground and providing an indication of the height of the implement above the ground, said arm comprising:

• a first variably curved, flexible, elongated elastomeric member having opposed proximal and distal ends, wherein said proximal end is coupled to said sensor and said distal end engages the ground;
• a second variably curved, flexible, elongated member comprised of a high strength material and coupled to and extending substantially between the proximal and distal ends of said first member, said second member having a proximal end coupled to said sensor;
• and
• a third variably curved high strength rigid member disposed adjacent to and coupled to the respective proximal portions of said first and second members, wherein all of the members have the same curvature and the curvature of the members allows a point of contact of said arm with the ground to move toward said sensor with a lowering of the height of the sensor above the ground.

An arrangement attached to an agricultural header assembly used in the harvesting of crops for controlling the height of said header assembly above the soil, said header assembly including a cutting mechanism for cutting crops, said arrangement comprising:

• a rotation sensor attached to the header assembly forward of said cutting mechanism;
• a curved, flexible ground engaging arm having a first end attached to said rotation sensor and a second opposed free end extending rearwardly and disposed below and forward of said cutting mechanism, wherein variations in the soil elevation causes deflection of said arm and displacement of said rotation sensor for providing a height control signal, and wherein as the height of the header assembly above the soil decreases, said arm engages the soil at an increasingly forward location along the length of said arm to allow for earlier detection of elevated soil as the height of the header assembly above the soil is reduced for avoidance of soil contact with the cutting mechanism;
• and
• a height controller coupled to the header assembly and to said rotation sensor and responsive to said height control signal for raising the header assembly when said arm encounters elevated soil.

Apparatus for measuring the height of an agricultural implement above the soil as said agricultural implement traverses a field, said apparatus comprising:

• a shaft mounted to the agricultural implement;
• rotation sensing means coupled to said shaft and responsive to rotation of said shaft for providing an output signal representing rotational displacement of said shaft;
• an arm having a proximal end connected to said shaft and a distal end engaging the soil, wherein said arm rotates in a first direction when said arm contacts upraised soil and rotates in a second opposed direction when said arm contacts a depression in the soil, and wherein rotation of said arm as detected by said sensing means provides an indication of the height of the agricultural implement above the soil;
• and
• biasing means for applying a downward force on the distal end of said arm engaging the soil, wherein said biasing means is adjustable for selecting a downward force applied to said arm over a range of downward forces.