A crop harvesting header for attachment to a combine harvester comprising:
- a main frame structure extending across a width of the header;
- a mounting assembly for carrying the main frame structure on a feeder house of the combine harvester by which the header is transported in movement in a forward direction generally at right angles to the width across ground including a crop to be harvested;
- the mounting assembly including an adapter for mounting on the feeder house so as to be raised and lowered with the feeder house relative to the combine harvester and a suspension system connected between the main frame structure and the adapter such that the main frame structure is movable upwardly and downwardly relative to the adapter;
- a crop receiving table carried on the main frame structure across the width of the header;
- a cutter bar across a front of the table arranged to move over the ground in a cutting action and carrying a sickle knife operable for cutting the crop as the header is moved forwardly across the ground for depositing the crop onto the table;
- a skid element on the main frame structure for engaging the ground so as to receive lifting forces from the ground;
- the skid element located behind the cutter bar and extending along the length of the cutter bar so that the cutter bar is supported adjacent the ground for cutting crop close to the ground as the skid element slides over the ground;
- a crop transport system on the table for moving the cut crop toward a discharge location of the header;
- the harvesting header being operable in a first mode of operation with the skid element engaging the ground and the cutter bar adjacent the ground and in a second mode of operation with the skid element and the cutter bar raised away from the ground;
- the main frame structure including a center frame portion, a first wing frame portion and a second wing frame portion;
- the first wing frame portion being connected to the center frame portion by a first pivot coupling which provides pivotal movement of the first wing frame portion relative to the center frame portion about a first pivot axis extending in a plane parallel to the forward direction;
- the first pivot coupling acting to support weight from the first wing frame portion while outboard weight from the first wing frame portion outboard of the first pivot coupling rotates the first wing frame portion about the first pivot coupling in a downward direction;
- the second wing frame portion being connected to the center frame portion by a second pivot coupling which provides pivotal movement of the second wing frame portion relative to the center frame portion about a second pivot axis extending in a plane parallel to the forward direction;
- the second pivot coupling acting to support weight from the second wing frame portion while outboard weight from the second wing frame portion outboard of the second pivot coupling rotates the second wing frame portion about the second pivot coupling in a downward direction;
- the suspension system including at least one spring connected between the main frame structure and the adapter so as to provide a variable spring lifting force acting to support the main frame structure for floating movement relative to the combine harvester;
- the mounting assembly including a center support assembly which communicates from the total spring lifting force of the suspension system a center lifting force against the weight of the center frame portion and weight from the first wing frame portion at the first pivot coupling and weight from the second wing frame portion at the second pivot coupling;
- a first interconnecting float linkage connected between the center frame portion and the first wing frame portion which communicates a first variable lifting force from the center frame portion to the first wing frame portion against the outboard weight of the first wing frame portion;
- a second interconnecting linkage connected between the center frame portion and the second wing frame portion which communicates a second variable lifting force from the center frame portion to the second wing frame portion against the outboard weight of the second wing frame portion;
- in the first mode of operation with the skid element engaging the ground, the float suspension system and first and second interconnecting linkages provide a downforce from the skid element on the ground which is balanced between the center frame portion and the first and second wing frame portions;
- a distance sensor for sensing changes in distance between a point on the main frame structure and a point on the adapter as the main frame structure moves upwardly and downwardly relative to the adapter and for generating an active distance signal proportional to the sensed changes in said distance;
- an automatic header height control system which receives the distance signal from the distance sensor and acts to raise and lower the feeder house in response to the distance signal from the distance sensor so as to raise and lower the feeder house relative to the main frame structure and attempt to maintain said distance at a required set value in a first mode of operation of the header;
- and
- a gauging system comprising:
- a first ground engaging member supported on the first wing frame portion at a location spaced outwardly from the center frame portion for engaging the ground so as to receive lifting forces from the ground;
- a second ground engaging member supported on the second wing frame portion at a location spaced outwardly from the center frame portion for engaging the ground so as to receive lifting forces from the ground;
- and
- at least one height sensor supported on the main frame structure proximate the center frame portion for sensing changes in height of the main frame structure from the ground at a location of said at least one height sensor as the main frame structure moves upwardly and downwardly relative to the ground and for generating an active height signal proportional to the sensed changes in said height;
- the height signal being receivable by the automatic header height control such that the automatic header height control acts to raise and lower the feeder house in response to the height signal from said at least one sensor so as to raise and lower the feeder house relative to the main frame structure and attempt to maintain said height at a required set value corresponding to said controlled distance of the outer gauge wheels in the second mode of operation of the header.