Combine Corn Head

Overview

A combine corn head is the header built specifically to harvest grain corn by snapping the ears off standing stalks and feeding only the ears into the combine. This is a different job from cutting small grains, where the whole plant is cut and threshed. With corn the stalk is thick and woody and the grain is held on a few large ears, so the efficient approach is to strip the ears off and leave the stalk standing or chopped in the field. A corn head does this one row at a time, with an identical mechanism repeated across the width, and it is built around fixed row spacing because each unit must line up with a planted row.

The header is a row of Row Unit units bolted to a common Header Frame. Each row unit snaps the ears off its row, a full-width Cross Auger collects the ears from every row and feeds them to the combine, the Driveline powers all the units, the Combine Hookup latches the head to the combine, and the Header Controls hold height and tune the snapping to the crop.

How the row unit snaps ears

The Row Unit is where the harvesting happens. As the combine drives into the field, a Row Snout guides each row of stalks into the unit, where a pair of fluted Stalk Roll rolls turning inward grab the stalk and pull it sharply downward. The ear, being far larger than the gap between the Stripper Plate plates, cannot follow the stalk down, so it snaps off cleanly at the shank while the stalk is pulled through and out the bottom. The Deck Plate deck plates set the gap between the stripper plates, and getting this gap right for the stalk diameter is the key to low loss: too wide and small stalks pull ears through, too narrow and stalks plug or shell grain. The snapped ear lands on a pair of Gathering Chain chains with lugs that carry it back to the auger, all driven by a Row Gearbox and Chain Sprocket sprockets running on Ball Bearing bearings.

Gathering and feeding

Behind the row units the Cross Auger collects the harvest. Snapped ears from every row are carried back by the gathering chains and dropped onto the auger, whose Auger Flighting flights move them inward from both ends to the center, where Feed Finger fingers push them into the combine feederhouse. Because a corn head delivers only ears and a little husk rather than whole plants, the combine behind it sees a clean, dense feed that threshes efficiently. The auger runs on Ball Bearing bearings sealed by Oil Seal seals against the dust and trash of corn harvest, which is heavier and dirtier than small-grain harvest.

Frame and dividers

The Header Frame sets the geometry. A heavy Toolbar carries the row units at the fixed row spacing they must match, a Floor Pan and Backsheet route the ears back to the auger, and between every pair of rows a long Point Divider noses ahead to part the rows and to lift up corn that has lodged or fallen so its ears are still gathered. Good dividers are what let a corn head harvest a storm-flattened field that would otherwise leave ears on the ground. The number of point dividers is one more than the number of rows, since there is one on each outside edge as well as between the rows.

Driveline and combine hookup

Power is shared along the head by the Driveline. A Input Gearbox takes the combine drive into a Cross Drive Shaft that runs the length of the toolbar and powers each Row Gearbox, with Universal Joint joints that let the shaft turn through any header fold. A key feature is the Slip Clutch on each row, so if one row hits a rock or a wad of trash and jams, only that row stops while the rest keep harvesting and the driveline is protected. The Combine Hookup latches the head to the combine the same way a grain header does, with a Mount Frame, Latch latches, and a Multi-coupler and Drive Coupler that connect everything in one motion, so an operator can swap heads to follow the harvest from corn to soybeans.

Controls, variants, and use

The Header Controls keep the head working at its best. A Header Controller runs auto height from Height Sensor sensors so the head rides at a steady level, and on modern heads a Deck Actuator adjusts all the deck plates on the move to match changing stalk size, which holds ear loss low across a variable field. Variants add stalk choppers under each row that shred the standing stalk for faster residue breakdown, and chopping corn heads are common where the next crop goes in soon after. Row counts run from six up to sixteen or more, with wider heads matched to higher-capacity combines. The corn head is the standard front for grain corn harvest, and because it strips only the ears it lets a combine move fast through a heavy crop while leaving the bulky stalk residue in the field.