Mechanical mechanism and model of rock breaking by edge tooth disk

In order to improve the crushing efficiency and rock breaking ability of coal and rock,a method of axial vi- bration and radial cutting of coal rock with wedge is proposed. Using the mechanical method of combination of com- pression,shear which are dominated at different stages,the paper analyzes the mechanical relationships of disc plate single tooth width in the extrusion,fracturing and fragmentation stages,as well as the disk with wedge to large lump coal rock collapse each process. Based on the superposition principle of compound effects,a mechanical model under various working conditions is built to reveal the mechanical mechanism of the broken coal rock on the edge of the tooth disc. The research shows that based on the mathematical description of the process of the formation of small pits,the generation of cracks and caving,through the process of caving of large chunks under the wedge,the mathematical mod- el of radial and axial load is built with the parameters of the disc structure and the rock breaking parameters. The axial upward movement of the composite axis is favorable to the fracture of coal rock. The radial and axial load of disc cutter increases with the increase of cutting thickness. The radial and axial loads of the disc are 11% and 4% difference be- tween the numerical simulated results. And the radial and axial loads of the disc are 3% and 18% when the composite action cutting is performed. The variation law of the parameters such as the thickness of the rock is consistent with the theoretical calculation and numerical simulation. The study provides a theoretical reference for the development of high efficiency and high crushing capacity.