Method for avoiding pointy edges at head and tail of thread in thread processing

Abstract

A method for avoiding pointy edges at the head and the tail of a thread in thread processing belongs to the technical filed of numeral control processing, which can improve surface quality and processing efficiency of a workpiece and effectively avoid the pointy edges at the head and the tail of the thread in the thread processing. The method comprises the following steps of 1 turning a spiral cylinder slot, increasing strength of a starting thread profile, cutting and removing one-second turn to three-fourth turn of the spiral cylinder slot from the internal circular face or the external circular face of the workpiece before the thread is processed on the workpiece, and removing original pointy edges in advance; and 2 processing the thread and feeding a cutter along the spiral cylinder slot. The coordinate of the starting point of the thread is consistent to that of a cutter track line of cut and removed spiral cylinder slot processed at last in the step 1.

Description

technical field [0001] The invention belongs to the technical field of numerical control machining, and in particular relates to a method for avoiding sharp edges at the beginning and end of the thread when machining the thread. Background technique [0002] The sharp edges at the beginning and end of the thread (such as figure 1 (shown) means that when the initial thread is turned, the width between the thread profile and the end surface of the workpiece forms a gradual sharp edge due to the helix of the thread itself. When the tool just cuts into the workpiece, the two cutting edges of the tool have a cutting force F perpendicular to the direction of the cutting edge on the workpiece (such as figure 2 shown); the sharp edge of the thread is thinner at the starting point of the thread, and it is easily deformed when stressed, and tilts outward. At the same time, the amount of deformation of the sharp edge varies with the sharp edge of the thread; from a macro perspective...

AI Technical Summary

Problems solved by technology

At present, in China, most people rely on manual grinding to remove the sharp edge of the thread or add some milling and grinding processes to remove the sharp edge of the thread; however, the processing process of these methods is not easy to control, and it is easy to damage the flank of the next thread during grinding; and the processing efficiency is low. It can finish grinding 4~6 workpieces with sharp thread edges, but the surface quality is poor, the highest can only reach Ra6.3, which seriously affects the assembly accuracy of workpieces

But there is no other way to avoid the sharp edge of the thread when processing the thread

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