Baler
A baler is a piece of farm machinery that is used to compress a cut, raked, crop (such as hay or straw) into bales and bind the bales with twine. There are several different types of balers that are commonly used.
Round baler
The most frequently used type of baler is a round baler. It produces cylindricaly shaped or 'round' bales. The hay is simply rolled up inside the baler using a number of rubberized belts. When the bale reaches a determined size, the twine that binds the bale is wrapped around the outside but not knotted. The back of the baler is opened up and the bale is discharged. These bales are 55-60 inches in diameter and about 60 inches in width. The bales weigh from 1100lb(500kg) to 1600lb(750kg).
The round baler was invented in 1971 by the Vermeer Company, which still produces them.
Rectangular baler
Another type of baler in common use produces large rectangular bales. The bales are bound with a half dozen or so strings of twine which is then knotted. The bales generally weigh somewhat more than round bales.
Square baler
A type of baler which is less common today produces small rectangular or 'square' bales. Each bale is about 15 in x 18 in x 38 in. The bales are wrapped with two, three, or sometimes four strands of twine, and knotted. The bales are light enough for a person to handle, about 45lb(20kg) to 60lb(25kg). To form the bale, the hay in the windrow is lifted by tines in the baler's 'pickup'. The hay is then dragged or augered into a chamber that runs along the length of the baler. A combination plunger and knife moves back and forth in this chamber. The knife cuts off the hay at the spot where it enters the chamber from the pickup. The knife is positioned just ahead of the plunger. The plunger compresses the hay into the bales. A measuring device measures the amount of hay that is being compressed, and at the appropriate time it triggers the mechanism (the knotter) which wraps the twine around the bale and ties off the bale.
This form of bale is no longer much used in commercial agriculture because of the costs involved in handling many small bales. However, it enjoys some popularity in small-scale, low-mechanization agriculture. Besides using simpler machinery and being easy to handle, these small bales can be used for insulation and building materials in straw-bale construction.
The baler for small square bales took on most of its present form in 1940, and was first manufactured by the New Holland Company. It is based on a 1937 invention for a twine tie baler with automatic pickup. Balers prior to this were manually wire tied. And even earlier, the baler was a stationary implement, with the hay being brought to the baler. The biggest change to this type of baler since 1940 is that they now are powered by the tractor through the power take-off instead of a mounted internal combustion engine.
See also
 
 
 
Other Meanings
A municipality of Aurora, Philippines. see Baler, Aurora
