According to the analysis of gear cutting motion and the design of three-axis linkage mechanism, the three-dimensional solid model of the new spiral bevel gear milling machine tool is established under the working environment of VERICUT. Because VERICUT’s main function is motion machining simulation, the intermediate transmission link of the gear cutting machine tool can be omitted and the structure of the machine tool can be simplified, which will not affect the simulation results. The component tree of the simplified model of the new spiral bevel gear milling machine tool is as follows. Add z-axis component and y-axis component to the matrix model of the machine tool respectively. Among them, the tool spindle is added to the z-axis assembly, and the components c-axis, x-axis, b-axis and a-axis are added to the y-axis assembly in sequence, and finally the gear blank fixture assembly is added to the a-axis assembly. Next, the simplified model of the corresponding structure of the machine tool is added to the corresponding components, and the simplified model of the six axis three linkage gear cutting machine tool required for machining spiral bevel gears in this paper is established, as shown in the figure.
In the figure: 1 machine tool horizontal base, 2 Y-axis moving platform, 3 horizontal rotary table, 4 X-axis moving platform, 5 tilting rotary table, 6 gear blank fixture, 7 tool spindle box and 8 column.
According to the simplified model of the new spiral bevel gear cutting machine, the machine has six moving axes, which are three moving axes (x-axis, Y-axis and Z-axis) and three rotating axes (a-axis, b-axis and c-axis). The three axes that need to be linked in the process of gear cutting are x-axis, a-axis and c-axis. In the process of gear cutting, the functions of each moving shaft are as follows:
① Adjust the rotation of the tilting rotary table in the b-axis direction so that the base cone of the gear blank is tangent to the horizontal plane;
② Control the tool spindle box to move along the Z direction on the column, so that the arc generating line of the blade is located on the tangent plane of the tooth blank base cone;
③ Adjust the position of the blank on the Y-axis and the initial feed axis to control the movement of the blank on the x-axis;
④ Three linkage movements required in the cutting process of spiral bevel gear: the movement V of gear blank along the boundary between adjustment area and cutting area, and the rotation movement of gear blank ω 1. The tooth blank rotates around the end of the tooth surface ω 2 is realized by controlling the movement of the gear cutting machine tool in the x-axis direction, the rotation of the a-axis of the tilting table and the rotation of the c-axis of the horizontal rotary table.