The increase of four-wheel tractor maneuverability

Along with the positive turning qualities, the shortcomings of three-wheeled tractors, associated with their instability, limited traction and coupling qualities and low total load capacity of tires, were noted. (Purpose of the study) The purpose of the study is increasing the maneuverability of a four-wheel universal row-crop tractor, ensuring minimal loss of productive areas in the headland zone at the edges of irrigated areas with cotton and other crops. (Materials and methods) The works on increasing the maneuverability of four-wheeled universal row-crop tractors are done at the Design and Technology Center for Agricultural Engineering. By increasing the angle of rotation of the steered wheels, the conditions to achieve a minimum radius of rotation of the tractor are created. (Results and discussion) There was developed a new design of the steering drive steering trapezoid of the universal row-crop tractor, where each half of the front cut symmetrical thrust from the side of the plain arm is shaded by a spring-loaded end disk, freely placed inside the hinged plain arm of the cage. In this case, the cavities of the cage, separating the end disk, are made in the form of communicating vessels, and the end disk itself is made in the form of a piston-valve, resting against the pressure of the spring on the saddle, cut at the bottom and connecting both cavities of the holder through two holes and ditches. (Conclusions) The new design of the steering trapezoid of the steering drive allows to increase the angle of rotation of the steered wheel during a turn, as a result when the tractor is turned, the axes of rotation of all three wheels in horizontal projection intersect at the intersection of the axes of symmetry of the fourth braked (right when turning «to the right» or left when «left turn») of the rear wheel. As a result, the intersection point of the axes of rotation of all the wheels is the center of the tractor’s turn, and it makes a turn around the braked rear wheel with a minimum radius and, thereby, eliminates the disadvantages of the well-known universal-row tractors.

tractor, rotation, steering trapezoid, steering gear, steered wheel, traction, plain arm, cage, radius