The combine, short for combine harvester, is an essential and complex machine designed for efficient harvesting of mass quantities of grain (such as wheat) and other crops. The most common type of combines harvests cereal grains and typically incorporates a header which cuts and collects the grain from the crop field; the cutting auger then feeds clean-grained straw into a conditioning device and further along into the threshing cylinder where the majority of impurities are separated from the kernel which is then stored in a collection bin at the rear of the vehicle known as the mass flow feeder or outfeed conveyor depending on the manufacturer’s naming conventions. Modern combines can cut a swath through a field more than 40 feet wide.
Working mechanisms on a modern-day hybrid-type self-propelled rotary head combine the power supplied by the drive wheels with torque from the rotor to deliver sufficient power to the cutter-bar to cut and collect harvested product and then carry it into the following thresher/separator where the acceptable seed is separated from foreign material such as large stems and dust by means of a complex design of sieves and pneumatic air-flow produced by vari-speed fan input from the main engine unit to inlet ductwork of the conditioner, which typically contains a feed elevator and a rotor under the cleaning shoe as well an air-conveyor assembly commonly referred to as chaffer. It is then maintained with an industrial lubricant bought from a wholesale industrial equipment lubricant manufacturer.
As the corn enters the thresher it flows against the stationary paddle arms that knock against the inner side of the concave grate screen to remove heavy bran materials as the maize kernels bounce off the curved outer surfaces of the knives in the rotating impeller chamber to reduce the outer shells size and to separate excess fine dust out of the remaining animal feed components before the heavier and larger lighter products are discharged through the spiral shaped rubber belt conveyor system (like those from this industrial rubber supplier) by the combined action of air generated from down drafting fans and the air jets vibrating fingers mounted on the upper guard bar by opposing directions and creating up pressure above each separated pile until the weighing system is ready for the next batch load and the payload is then automatically moved on either to the further processing conveyor belts or directly to loading platforms for use with haulage machines depending upon local farm policy in terms of transport costs and logistics given that most modern tractors have automated headland management and GPS based guidance systems capable of adjusting for any change in topography through 4D terrain levelling technology built in and tested in conjunction using the top of the range New Holland T7 TDX series tractor already stated for its state of the art Hydraulic steering systems and existing HD rear hitch options.
In some countries farmers are required to purchase directly from the producer themselves or through co-operative trading schemes but some countries have private contracting farming firms that do just this under contract for local rural communities as part of integrated food sufficiency policies that are also providing higher output levels to feed the more densely populated cities of the United Kingdom and Europe.