Constructive layout for small rotor of straight-flow rotary ripper
Authors: Nikolaev V. A. 
Published: July 2023

Introduction. The problem of accelerating and cheapening the construction of roads without reducing their quality can be solved by creating a complex of continuous units. Units, following each other, carry out the whole complex of works aimed at roads construction. One of the elements of the continuous unit that forms the ditch is a straight-flow rotary ripper. It was found that in order to excavate the soil near the axis of rotation of the rotor of a straight-flow rotary ripper, a small rotor with a higher angular velocity should be installed, coaxially with a large rotor. The use of straight-flow rotary rippers for soil development is constrained by insufficient theoretical substantiation of their parameters. Before analysing the interaction of the elements of the working bodies of the straight-flow rotary ripper with the soil, it is necessary to clarify the structural layout of the small rotor.

The method of research. The small rotor should contain two knives connected at the periphery by a disc to give rigidity to the knives; the cross-section of the knives is triangular with a sharpening angle of 20 °, for maximum transformation of the angle of sharpening, the knives must have a saber-shaped shape; two teeth located on the disk to loosen the soil and shift it towards the knives; a shaft tip of the small rotor, the diameter of which must exceed the width of the knife at the point of its connection with the shaft tip; a spiral knife at the end of the shaft tip to loosen the soil and shift it towards the knives. By constructing projections on the transverse-vertical plane of the blade of the knife, the tooth and the disc of the small rotor, when there is a different angle of deviation of the blade in the cutting plane, it is possible to identify the basic geometric parameters of the elements of the small rotor of the straight-flow rotary ripper. Applying the well-known formulas of theoretical mechanics, we will determine the angular velocity of the small rotor and other kinematic parameters.

Results. Based on the method of constructing a projection on the transverse-vertical plane of the blade of a knife, a tooth and a disc of a small rotor, when there is a different angle of deviation of the blade in the cutting plane, the main geometric parameters of the elements of the small rotor of a straight-flow rotary ripper are revealed. According to the formulas of theoretical mechanics, the following are determined: the circumferential velocity of the point on the surface of the shaft, the angular velocity of the small rotor, the time of one revolution of the small rotor, the path of the unit for one revolution of the small rotor. The dependence of the radius of the point on the blade of the knife of the small rotor on the angle of rotation of the beam is constructed and approximated.

Conclusion. By constructing projections on the transverse-vertical plane of the knife blade at different angles  of deflection of the blade in the cutting plane the optimal shape of the knife blade has been determined, the transformation of the angle of sharpening of the blade depending on the angle of deviation of the cutting plane from the plane perpendicular to the blade, the front, back corner of the knife blade, the profile of the blade of the small rotor knife in space was revealed, a structural layout of the small rotor was made, the circumferential velocity of the point on the surface of the shaft, the angular velocity of the small rotor, the time of one revolution of the small rotor, the path of the unit for one revolution of the small rotor are calculated.