Farm tractor
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Tractor is a self propelled power unit having wheels or tracks for operating agricultural implements and machines including trailers. Tractor engine is used as a prime mover for active tools and stationary farm machinery through power take-off shaft (PTO) or belt pulley.
Tractor development
• The present tractor is the result of gradual development of machine in different stages. History of tractor development is given below in chronological order.
• 1890: The word tractor appeared first on record in a patent issued on a tractor or tractor engine invented by George H.Harris of Chicago.
• 1906: Successful gasoline tractor was introduced by Charles W. Hart and Charles H. Parr of Charles city, Iowa (48A).
• 1920-1924: All purpose tractor was developed.
• 1936-1937: Diesel engine was used in tractor and pneumatic tires were introduced.
• 1960-61: Tractor manufacturing was started in India by first manufacturer M/s Eicher Good Earth.
• 1971: Escorts tractor Ltd started producing ford tractor.
• 1982 : Universal tractors were established
TractorClassification and selection of tractors
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Classification
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Tractors can be classified into three classes on the basis of structural design:
(i) Wheel tractor
(ii) Crawler tractor (track type or chain type)
(iii) Walking tractor (power tiller).
Different types of tractor
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(i) Wheel tractor: Tractors, having three of four pneumatic wheels are called wheel tractors. Four wheel tractors are most popular everywhere.
(ii) Crawler tractor: This is also called track type tractor or chain type tractor. In such tractors, there is endless chain or track in place of pneumatic wheels.
(iii) Power tiller: Power tiller is a walking type tractor. This tractor is usually fitted with two wheels only. The direction of travel and its control for field operation is performed by the operator, walking behind the tractor. On the basis of purpose, wheeled tractor is classified into three groups: (a) General purpose (b) Row crop and (c) Special purpose.
(a) General purpose tractor: It is used for major farm operations such as ploughing, harrowing, sowing, harvesting and transporting work. Such tractors have (i) low ground clearance (ii) increased engine power (iii) good adhesion and (iv) wide tyres.
(b) Row crop tractors: It is mainly designed to work in rows like planting, interculture etc. Such tractor is provided with replaceable driving wheels of different thread widths. It has high ground clearance to save damage of crops. Wide wheel track can be adjusted to suit inter row distance.
(c) Orchard tractors: These are special type of tractors, are mainly used in orchards. Such tractors have (i) less weight (ii) less width and (iii) no projected parts.
(d) Special purpose tractor: It is used for definite jobs like cotton fields, marshy land, hill sides, garden etc. Special designs are there for special purpose tractor.
