Tooth path generation method for bidirectional cutting edge tool

A tool path generation method for a bidirectional cutting edge tool, the bidirectional cutting edge tool having a second edge and a first edge which are axially connected and have opposite running directions for cutting, characterized in that the rail generation method comprises:

• step 1:
• creating a part contour machining coordinate system, and acquiring contour feature information of a part and tool geometry information, wherein the contour feature information of the part comprises a feature surface and a part thickness, and the tool geometry information comprises the diameter of the tool, the length of the second edge and the length of the first edge;
• step 2:
• considering upper and lower side lines of the feature surface of the part as contour side lines, and determining a contour side line having a longer length as a driving line and a contour side line having a shorter length as an auxiliary driving line based on the lengths of the contour side lines;
• step 3:
• extending both ends of the driving line in a G1 continuous manner, with an extended length being larger than the radius of the tool to ensure that a starting position of the tool path is located outside the contour, while extending the auxiliary driving line in the G1 continuous manner to ensure that a rule plane created by two end points of the driving line intersects with the auxiliary driving line;
• step 4:
• discretizing the driving line to obtain a plurality of driving points for contour machining, and creating the rule plane of the driving line at each driving point;
• step 5:
• setting a point obtained by the intersection of the rule plane at each driving point and the auxiliary driving line as a tool axis control point, a vector between each driving point to its respective tool axis control point being a tool axis vector r(ir, jr, kr) at a current driving point, wherein in the current machining coordinate system, if a Z-direction value Zq of the driving point is less than a Z-direction value Zk of the tool axis control point, the tool axis vector is r(ir, jr, kr), otherwise the tool axis vector is −r(ir, jr, kr);
• step 6:
• calculating an actual tool position point of the bidirectional cutting edge tool by:
• taking the driving point as Pi(xi, yi, zi), the diameter of the tool as D, the thickness of the part as H, the Z-direction value of the driving point as Zq, the Z-direction value of the control point as Zk, the length of the second edge of an outer section of the tool as Lb, an actual tool position point as P(x, y, z), a tool axis unit vector as r(ir, jr, kr), and an unit vector in a tool advancing direction as v(iv, jv, kv), calculating the actual tool position point P(x, y, z) at the driving point by the following formula:
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• and step 7:
• repeating step 5 and step 6 to calculate the actual tool position point and the tool axis vector corresponding to each driving point until the calculation of all the actual tool position points and tool axis vectors is completed, so as to form a complete contour machining path of the bidirectional cutting edge tool.