How Do Combines Work? (Video)
During harvest season, combine harvesters can be found all over Illinois fields. But what exactly do they do? Learn how this versatile machine changed the farming industry by streamlining the process of harvesting grains.
What Is a combine?
In 1835, Hiram Moore built and patented the first combine harvester in the United States. Before its invention, nearly 90% of the U.S. population worked on farms. Combine harvesters get their name from the way they automatically combine the processes of harvesting and separating of grain crops into one step, an otherwise laborious series of operations once done separately. It can harvest crops like corn, wheat, soybeans, rye, barley and oats. After gathering crops, the combine cuts them at the base, feeds them into a threshing drum that shakes the grains away from their stalks and sweeps the unwanted material to the back of the machine.
The Anatomy of a Combine
- The header cuts off the plant close to the ground and moves the whole plant into the machine. Farmers switch out the header depending on if they are harvesting corn, soybeans or other crops.
- The cut crops move toward the center via spinning augers and travel up a conveyor.
- The threshing segment of the combine beats the cut crops to break and shake the grains away from their stalks.
- The separated grains travel by conveyor into a grain tank. The unwanted stalks, husks, cobs and/or bits of leaves – known as chaff or residue – move along different conveyors, as more grain falls through into the tank.
- When the grain tank is full, a tractor with a grain cart on the back pulls alongside the combine. The grain is carried up from the tank by an elevator and shoots out of a side pipe, or unloader, into the grain cart.
- The residue exits the back of the machine to either be spread across a wide area or baled as straw to use for animal bedding. Most machines use a straw chopper to make it smaller and more manageable.