Rough machining method of helical surface of hourglass worm

Abstract

The invention discloses a rough machining method suitable for helical surfaces of various hourglass worms, belonging to a method for machining hourglass worms. The invention adopts the technical scheme that a hourglass worm 1, a turning tool 2, a turning tool marking line 3, a worm axial line 4, a turning tool revolving axial line 5 and a common perpendicular thereof 6 are comprised, wherein the worm axial line and the turning tool revolving axial line are vertically interlaced, perpendicular foots are respectively O and O', the turning tool marking line 3 passing through the point O', a leftcutter point N and a right cutter point M are arranged in a plane determined by the worm axial line 4 and the common perpendicular 6, wherein the revolving radius of the left cutter point N and the revolving radius of the right cutter point M are Rd. According to a principle of hourglass worm forming, an annular surface with the radius of Rd and a series of corresponding points on a left helical surface and a right helical surface at different axial section parts when the corresponding center distance of the same helical groove of the hourglass worm 1 is OO' are obtained. A cutter point between the cutter points N and the cutter point M is used for turning the part on the current annular surface of the same helical groove of the hourglass worm 1 between an engaging-in end and an engaging-out end, and turning whole body of the same helical groove along with the continuous reduction of the center distance OO'. The invention solves the problem of hourglass worm grinding allowance homogenization.

Description

technical field [0001] The invention relates to a rough machining method for the helical surface of a torus worm, which belongs to the processing method of a torus worm. Background technique [0002] The helical surface of the straight-profile toroidal worm is turned by the straight cutting edge of the turning tool, and the turning efficiency is high. The grinding wheel is ground with the shape of the shape, and the grinding efficiency is relatively low. Therefore, the rough machining method of the helical surface of various enveloping toroidal worms is usually divided into two steps: the first step is the turning method of the helical surface of the straight profile toroidal worm The helical groove of the worm is opened, and the second step is to grind out various toroidal worm helical surfaces with a grinding wheel of a corresponding shape. However, since the helicoids of other toroidal worms are different from those of straight-profile toroidal worms, the grinding allowa...

AI Technical Summary

Problems solved by technology

The principle of the enveloping method is the same as that of the plane enveloping worm, and the grinding allowance is uniform, but the disadvantage is that it needs to make a special plane milling cutter and a special milling head, which requires high rigidity of the machine tool, and needs to rough out the spiral groove first. This method is not widely used

The modification methods include the traditional symmetrical modification method, the segmental homogenization method developed by Zhou Liangyong, and the comprehensive modification homogenization method. The method of turning or milling is used. The modification principle is to change the center distance, transmission ratio and main base circle, etc. parameters, so that the modified curve of the rough machining worm is close to but not consistent with the modified curve of the plane enveloping toroidal worm, so the homogenization effect is not as good as that of the envelope method

[0004] Shi Liping, Wu Yuguo, and Li Xiaobin explained in the article "Numerical Control Machining of Plane Secondary Enveloping Toroidal Worm Pair" in the 11th issue of "Combined Machine Tool and Automatic Processing Technology" in 2008 that the use of ball-end cutters on CNC grinding machines is accurate Grinding the helicoid of the plane enveloping torus worm, and calculating the coordinates (x, y, z) of the spherical center of the ball nose cutter, but it is still necessary to open the helical groove according to the straight profile torus worm or mill the helicoid with a plane milling cutter

Images