Steering apparatus of for a tractor

A steering apparatus for turning front wheels of a tractor, comprising:

• a steering cylinder receiving a steering force transmitted by hydraulic pressure when a driver manipulates a steering wheel;
• a first four-bar link structure provided in a medial portion of the steering apparatus, the first four-bar link structure being swung to a left or right by extension or retraction operation of the steering cylinder;
• and second four-bar link structures respectively provided on left and right ends of the first four-bar link structure,
• wherein the steering cylinder comprises left and right cylinder rods extended and retracted to the left and the right and is provided parallel to a front wheel axle housing at a position spaced apart from the front wheel axle housing by a predetermined distance, and the first four-bar link structure is configured such that ends of the left and right cylinder rods are respectively hinged to swing links,
• wherein the steering cylinder is coupled at a medial portion thereof to a steering cylinder coupling link hinged to a steering cylinder bracket installed on the front wheel axle housing, wherein the steering cylinder coupling link is configured such that the steering cylinder is prevented from being moved to the left or the right and is allowed to be moved forwards or rearwards by a predetermined distance,
• wherein the steering cylinder is swung upwards and downwards in a seesaw manner in which a left end of the steering cylinder moves upwards or downwards based on the steering cylinder coupling link while a right end thereof moves downwards or upwards.