Calculating method for envelop feature lines of rotary cutter based on enveloping theory and division of longitudes

Abstract

Provided is a calculating method for envelop feature lines of a rotary cutter based on an enveloping theory and division of longitudes. The calculating method comprises five steps: step 1, establishing a vector field on a designed curved surface according to the planning direction of a cutter path; step 2, dividing longitudes of the cutter and establishing a local coordinate system to each longitude; step 3, projecting set points of longitudes to the designed curved surface of a workpiece and acquiring the local feeding direction of a corresponding projective point in a direction field; step 4, utilizing that dot product between corresponding normal vector of the cutter curved surface of the longitudes in an envelope equation and the local feeding direction of the longitudes is zero as a condition to calculate effective feature points; step 5, calculating distances among effective feature points of all the longitudes to the curved surface of the workpiece in order to acquire the minimum distance of lines. The calculating method for envelop feature lines of the rotary cutter based on the enveloping theory and division of longitudes has a great application prospect in the technical field of numerical control machining of complex surfaces.

Description

technical field [0001] The invention relates to an accurate solution method for the envelope motion characteristic line of an end milling tool with a complex busbar structure in the process of end milling a complex curved surface in numerical control machining, in particular to a rotary tool envelope characteristic line based on envelope theory and meridian division The calculation method belongs to the technical field of numerical control machining of complex curved surfaces. Background technique [0002] In NC machining of complex curved surfaces, the calculation of the error distribution between the tool motion envelope and the design surface is the basis for optimizing the tool position and tool path according to the principle of maximizing the line width. In general, the envelope surface of the tool is determined by the determined tool trajectory and attitude, but when the tool trajectory and attitude are not determined, the envelope surface of the tool cannot be solved...

AI Technical Summary

Problems solved by technology

Chen Zhitong proposed the warp and latitude method of discrete tools into a set of warp and latitude, which plays an important role in the tool path planning where the feed direction is undetermined, but the proposed method is to determine the effective features by calculating the distance from the longitude and latitude to the design surface line, this method has sufficient accuracy in the part located in the tolerance zone, but it cannot calculate the state of the effective feature line in the part outside the tolerance zone, so there is a certain error

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