An open curve profile rounding and chamfering macro programming method

Abstract

The application provides a macro-program compiling method for open curve profile chamfering, which comprises the following steps: firstly, a polar coordinate programming mode is applied to construct a distance variation parameter #13 from a tool center to a machined profile at an arbitrary angle position; and then a plurality of local coordinate systems are set to make the distance variation parameter #13 established in the previous step continuously move along the machining track of the tool. Thus, the macro-program compiling for open curve profile chamfering is realized. The macro-program compiling method effectively combines the polar coordinate and local coordinate system, and overcomes the current situation that the open curve profile chamfering cannot be compiled by simple mathematical calculation and logical operation.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of numerical control machining, and particularly relates to a macro program compiling method for open curve profile chamfering and rounding. BACKGROUND

[0002] Referring to the attached Figure 9 , 10 , 11, the document "Research on Macro Program for Profile Chamfering and Rounding", New Technology and New Process, 2013, No. 1, discloses a macro program compiling method for profile chamfering and rounding. The method regards the tool cutting trajectory as the closed envelope line offset outward and inward along the profile at equal intervals. For the envelope line offset outward, the distance variation parameter #12 of the tool center to the machined profile is constructed on the X and Z planes by mathematical calculation, and a transition circular arc with a radius of the parameter #12 is constructed at the right angle of the outer profile to make the envelope line closed. Meanwhile, the angle variable θ1 is established on the X and Y planes by logical operation to realize the parameter equation of the angle variable θ1 varying along the profile, thereby realizing the macro program compiling for the outer profile rounding. For the envelope line offset inward, the distance variation parameter #5 of the tool center to the machined profile is constructed on the Y and Z planes by mathematical calculation, and the angle variables θ2 and θ3 are established on the X and Y planes by logical operation to realize the parameter equation of the angle variables θ2 and θ3 varying along the profile, thereby realizing the macro program compiling for the inner profile chamfering. The macro program compiling method disclosed in the document reduces the repeated programming of the curve profile rounding and chamfering with the same shape and different sizes, reduces the character number, saves the memory, and makes the programming more convenient and easier. However, the method is only suitable for the macro program compiling for the closed curve profile rounding and chamfering, and cannot be applied to the macro program compiling for the open curve profile rounding and chamfering, so the method disclosed in the document has limitations.

[0003] In summary, the existing macro program compiling method for profile rounding and chamfering is not suitable for the open curve profile rounding and chamfering, and the macro program compiling method for curve profile rounding and chamfering by mathematical calculation and logical operation has limitations. SUMMARY

[0004] The present application solves the technical problem that the existing technical method cannot realize the macro program compiling for the open curve profile rounding and chamfering by simple mathematical calculation and logical operation. The present application provides a macro program compiling method for open curve profile rounding and chamfering. The method first constructs the distance variation parameter #13 of the tool center to the machined profile at an arbitrary angle position by polar coordinate programming, and then makes the distance variation parameter #13 continuously move along the machining trajectory of the tool by setting multiple local coordinate systems. Thus, the macro program compiling for the open curve profile rounding and chamfering is realized.

[0005] The technical scheme of the present application is: a macro program compiling method for open curve profile chamfering and rounding, comprising the following steps:

[0006] Step 1: divide the open curve profile into several segments, and make the center of the circular arc segment, and measure the X and Y coordinate values of the center.

[0007] Step 2: respectively extend the two end points of the open curve profile, so that the tool lower point and the tool exit point are both outside the workpiece.

[0008] Step 3: realize the open curve profile chamfering macro programming in polar coordinates.

[0009] Step 4: determine the distance change parameter of the tool center to the machined profile.

[0010] Further, in step 1, the open curve profile is divided into ac segment, cd segment, de segment, ef segment, fg segment and gb segment six parts, wherein ac segment is a straight line segment, and the other segments are circular arc segments, the center of cd segment circular arc 1 is defined as O1, the center of de segment circular arc 2 is defined as O2, the center of ef segment circular arc 3 is defined as O3, the center of fg segment circular arc 4 is defined as O3, and the center of gb segment circular arc 5 is defined as O4.

[0011] Further, in step 1, cd segment circular arc 1, ef segment circular arc 3 and fg segment circular arc 4 are concave circular arcs, and de segment circular arc 2 and gb segment circular arc 5 are convex circular arcs.

[0012] Further, in step 2, the left end point a of the open curve profile is extended to point A, and line segment CA is perpendicular to line segment aA, the right end point b of the open curve profile is extended to point B, and line segment BD is directed to the center O4. The purpose of extending to points A and B is to make the tool lower point and the tool exit point outside the workpiece; points C and D act as a bridge to enable the macro variable to change continuously.

[0013] Further, in step 3, the following sub-steps are included:

[0014] Step 3.1: polar coordinates and parameter definition of straight line segment and circular arc segment in polar coordinates;

[0015] Step 3.2: the origin of the machining coordinate system coincides with the zero point O of the modeling coordinate system, and the X and Y coordinate values of the O point are both set to 0, and the Z zero point is on the upper surface of the workpiece;

[0016] Step 3.4: according to the order of O-O1-O2-O3-O4-O, the X and Y coordinate values of the O point and the circular arc centers O1 to O4 are respectively substituted into the main coordinate system code and the local coordinate system code in sub-step 2 and sub-step 3;

[0017] Step 3.5: Draw auxiliary line segments from the center of the circular arc O1 to O4 to each point of c, d, h, e, i, f, g, j, B, and measure the length of each line segment and the included angle between each line segment and the X-axis, so that when the open curve profile is programmed in polar coordinates, the open curve profile is programmed in the order specified in the format of sub-step 1.

[0018] Further, in step 4, the following sub-steps are included:

[0019] Step 4.1: Calculate the tangent value of the chamfer angle

[0020]

[0021] Step 4.2: Distance variation parameter #13 of the tool center to the machined profile

[0022]

[0023] Let the downward cutting depth be t, and the tool radius be The chamfer width of the open curve profile is m, and the chamfer depth is n; wherein t, d1, m, n are arbitrary values, the value of t is less than or equal to the value of n, and the value of d1 is greater than or equal to the value of m.

[0024] Further, in step 4, the downward cutting depth variable parameter t is #2, the tool radius parameter is #7, the chamfer angle tangent value variable parameter is #8, and the distance variation parameter γ of the tool center to the machined profile is #13, i.e. #13 = #2 / #8+#7; when using a ball cutter, the tool radius parameter #7 is 0, and the distance variation parameter #13 of the tool center to the machined profile is #2 / #8.

[0025] Further, in step 4, the outer profile is offset outward by #13, the inner profile is offset inward by #13, the convex circular arc radius is added by #13, and the concave circular arc radius is reduced by #13. When machining the outer profile, the envelope line is offset outward by #13, so #13 is added. When the inner profile is offset inward, the envelope line is offset inward by #13, so #13 is subtracted. The convex circular arc is added by #13, and the concave circular arc is reduced by #13, so that the polar radius in step 1 can be flexibly added or subtracted by the value of parameter #13, realizing the macro programming of parameter #13 with the tool trajectory movement.

[0026] Inventive effect

[0027] The technical effect of the present application is that, with reference to the implementation process of steps one to four in the specific embodiment, the distance variation parameter #13 of the tool center to the machined profile can be established in polar coordinates at any angle, and the distance variation parameter #13 can be continuously moved by setting a local coordinate system to follow the machining trajectory of the tool, thereby realizing the macro programming of open curve profile rounding and chamfering in polar coordinates. Compared with the method described in the literature, the present method does not need to construct the parameter equation of the angle variable θ1, θ2, θ3 in the X, Y plane, and can be used in the macro programming of open curve profile rounding and chamfering, the program is short and the efficiency is improved. The present method overcomes the current situation that the existing technical method cannot perform macro programming of open curve profile rounding and chamfering through simple mathematical calculation and logical operation by effectively using the macro programming method of polar coordinates and local coordinate system. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 is a schematic diagram of the part geometry structure of the method of the present application.

[0029] Figure 2 is a schematic diagram of the structure of the 5 arc segments and the O1 to O4 circle centers on the open curve profile of the method of the present application.

[0030] Figure 3 is a schematic diagram of the structure of the auxiliary line segments aA, CA, BD and the auxiliary arc line segment bB of the method of the present application.

[0031] Figure 4 is a schematic diagram of the structure of the auxiliary line segments made by the polar coordinate programming of each circle center to each arc segment of the method of the present application.

[0032] Figure 5 is a schematic diagram of the position of the machining zero point of the method of the present application for programming the chamfering of the open curve profile.

[0033] Figure 6 is a schematic diagram of the structure of the part geometry front view of the method of the present application.

[0034] Figure 7 is a schematic diagram of the structure of the F-F section of the part geometry front view of the method of the present application.

[0035] Figure 8 is a schematic diagram of the geometric parameters of the chamfering part of the part geometry of the method of the present application.

[0036] Figure 9 is a schematic diagram of the machining principle and the algorithm of the logical operation parameters of the distance variation parameter in the background art.

[0037] Figure 10 is a schematic diagram of the algorithm of the distance variation parameter #12 of the tool center to the machined profile of the outer profile rounding of the background art.

[0038] Figure 11 is the algorithm schematic diagram of the distance variation parameter #5 from the inner contour chamfer tool center to the machined profile in the background art. DETAILED DESCRIPTION

[0039] In the description of the present application, it needs to be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise" and the like are based on the orientation or positional relationship shown in the drawings, which are only for the convenience of describing the present application and simplifying the description, and are not intended to indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0040] Referring to the accompanying drawings Figure 1 to the accompanying drawings Figure 8 , the method comprises the following steps:

[0041] Step one, draw the open curve profile graph with MasterCam8.0 software, there are 5 circular arcs on the open curve profile, make the center O1 of cd segment circular arc 1, the center O2 of de segment circular arc 2, the center O3 of ef segment circular arc 3, the center O3 of fg segment circular arc 4, and the center O4 of gb segment circular arc 5 in turn.

[0042] Step two: extend the left end point a of the open curve profile to point A, and make line segment CA perpendicular to line segment aA, extend the right end point b of the open curve profile to point B, and make line segment BD towards the center O4.

[0043] Step three, determine the coordinate values of each point in the program in polar coordinates.

[0044] Substep one

[0045] First of all, understand the meaning of polar coordinate programming, the polar radius value refers to the distance from the end point coordinate to the programming origin, and the angle value refers to the included angle between the line connecting the end point coordinate and the programming origin and the X axis. For the straight line segment in programming, the polar radius coordinate value is input after X, and the polar angle coordinate value is input after Y; for the circular arc segment, the polar radius coordinate value is input after X, the polar angle coordinate value is input after Y, and the polar radius coordinate value is input after R.

[0046] Substep two

[0047] Let the programming origin of the machining coordinate system coincide with the modeling coordinate system zero point O, and the X and Y coordinate values of O point are both set to 0, and the Z zero point is on the upper surface of the workpiece.

[0048] Substep three

[0049] Use absolute coordinate programming, with the programming code G90. Following sub-step two, set the coordinates of point O as the primary coordinate system. Then, sequentially find the X and Y coordinates of the arc centers O1, O2, O3, and O4 from step one in the primary coordinate system, and set them as local coordinate systems. These local coordinate systems are subordinate to the primary coordinate system. The programming origin code for the primary coordinate system is G90G54 X_Y_, while the programming origin code for the local coordinate system is G90 G54 G52 X_Y_.

[0050] Sub-step four

[0051] To ensure continuous movement of the programmed trajectory, the programming origin changes sequentially in the order of O-O1-O2-O3-O4-O. The X and Y coordinate values ​​of point O in the main coordinate system are both 0. The X and Y coordinate values ​​of the arc centers O1 to O4 are substituted sequentially according to sub-step three.

[0052] Sub-step five

[0053] Draw line segments O1c and O1d from center O1 to arc 1; draw line segments O2h and O2e from center O2 to arc 2; draw line segments O3i and O3f from center O3 to arc 3; draw line segment O3g from center O3 to arc 4; draw line segment O4j from center O4 to arc 5; and draw line segment O4B from center O4 to point B. Measure the lengths of the line segments from the arc centers O1 to O4 to their respective endpoints c, d, h, e, i, f, g, j, and B, as well as the angle between each line segment and the X-axis. Input these values ​​sequentially in the polar coordinate programming.

[0054] See appendix Figure 1 , 9 10, 11

[0055] Step 4: Determine the distance variation parameter from the tool center to the machined contour #13

[0056] Let the depth of cut in the Z direction be t, the tool radius be d1 / 2, the chamfer width of the open curve profile be m, and the chamfer depth be n.

[0057] The tangent of the chamfer angle

[0058] Distance variation parameter from tool center to machined contour

[0059] Note: To use the above variable parameters when writing macro programs, let the depth of cut variable parameter t be #2, and the tool radius parameter... #7, the chamfer angle tangent value variable parameter The parameter γ, which represents the change in distance from the tool center to the machined contour, is #13, i.e., #8. When machining with a ball end mill, the tool radius parameter #7 is 0, and the distance from the tool center to the machined contour varies.

[0060] In order to ensure the consistency of distance variation when offsetting the machining contour, the outer contour is offset outward by #13, the inner contour is offset inward by #13, and the convex circular arc radius is added by #13 and the concave circular arc radius is subtracted by #13. The identification of the convex and concave directions of the circular arc is based on whether the machining curve contour is on the outside or the inside. In the present application, the machining is on the outside of the open curve contour. From the point a to the point b, the cd segment circular arc 1, the ef segment circular arc 3 and the fg segment circular arc 4 are concave circular arcs, and the de segment circular arc 2 and the gb segment circular arc 5 are convex circular arcs.

[0061] The program comparison before and after the improvement of the present application is shown in Table 1.

[0062] Table 1 Program comparison before and after the improvement of the present application

[0063]

[0064]

[0065]

[0066] The program comparison of the method used in the literature and the method of the present application is shown in Table 2.

[0067] The program comparison of the method used in the literature and the method of the present application

[0068]

[0069]

[0070]

[0071]

[0072]

[0073] In the method of the present application, the polar coordinate programming method is used to construct the distance variation parameter #13 from the tool center to the machined contour at any angle position, and the method of setting multiple local coordinate systems is used to make the variation parameter #13 continuously move along the machining trajectory of the tool, so as to realize the macro program programming of the open curve contour fillet and chamfer. The method simplifies the programming and improves the efficiency, and is suitable for the macro program programming of the open curve contour fillet and chamfer.

Claims

1. An open curve profile rounding chamfering macro programming method, characterized in that, It comprises the following steps: Step 1: divide the open curve profile into several segments, and make the center of the circular segment, measure the X, Y coordinate values of the center; Divide the open curve profile into ac segment, cd segment, de segment, ef segment, fg segment and gb segment six parts, wherein ac segment is a straight line segment, and other segments are circular segments, define the center of cd segment circular arc 1 O1, the center of de segment circular arc 2 O2, the center of ef segment circular arc 3 O3, the center of fg segment circular arc 4 O3, and the center of gb segment circular arc 5 O4; Step 2: respectively extend the two end points of the open curve profile, so that the lower knife point and the knife point of the tool are outside the workpiece; Extend the left end point a of the open curve profile to point A, and make line segment CA perpendicular to line segment aA, extend the right end point b of the open curve profile to point B, and make line segment BD towards the center O4; The purpose of extending to A point and B point is to make the lower knife and the knife point of the tool outside the workpiece; C point D point plays a bridge role, so that the macro variable can change continuously; Step 3: realize the open curve profile chamfer macro programming in polar coordinate mode; It comprises the following sub steps: Step 3.1: polar coordinate and parameter definition about straight line segment and circular segment in polar coordinate; Step 3.2: set the origin of the machining coordinate system to coincide with the zero point O of the modeling coordinate system, and the X and Y coordinate values of O point are set to 0, and the Z zero point is on the upper surface of the workpiece; Step 3.4: according to the order of O-O1-O2-O3-O4-O, the X, Y coordinate values of O point and circular center O1 to O4 in sub step 2 and sub step 3 are substituted into the main coordinate system code and local coordinate system code respectively; Step 3.5: make auxiliary line segment from circular center O1 to O4 to c, d, h, e, i, f, g, j, B points, and measure the length of each line segment and the angle between each line segment and X axis, so as to realize the polar coordinate programming of open curve profile in turn according to the format specified in sub step 1; Step 4: determine the distance change parameter of tool center to machined profile; It comprises the following sub steps: Step 4.1: calculate the tangent value of chamfer angle Step 4.2: distance change parameter #13 of tool center to machined profile Let Z be the downward cutting depth, the tool radius be , the chamfer width of the open curve profile be m, and the chamfer depth be n; wherein t, d1, m, and n are arbitrary values, the value of t is less than or equal to the value of n, and the value of d1 is greater than or equal to the value of m. According to the above steps, it is not necessary to construct the parameter equation of angle variable in X, Y plane θ1, θ2, θ3, and it can be used in the macro programming of open curve profile chamfering, the program is short and the efficiency is improved; It can establish the distance change parameter #13 of tool center to machined profile in polar coordinate mode at any angle, and can make the distance change parameter #13 follow the machining track of the tool to move continuously through the method of setting local coordinate system, so as to realize the macro programming of open curve profile chamfering in polar coordinate mode.

2. An open curve profile rounding and chamfering macro programming method according to claim 1, characterized in that, In step 1, cd segment circular arc 1, ef segment circular arc 3 and fg segment circular arc 4 are concave circular arcs, and de segment circular arc 2 and gb segment circular arc 5 are convex circular arcs.

3. An open curve profile rounding and chamfering macro programming method according to claim 1, wherein, In the step 4, the variable parameter t of the lower tool depth is #2, the tool radius parameter is #7, the variable parameter of the chamfer angle tangent value is #8, and the parameter γ of the distance change of the tool center to the machined profile is #13, i.e. #13=#2 / #8+#7; when a ball tool is used for machining, the tool radius parameter #7 is 0, and the distance change parameter #13 of the tool center to the machined profile is #2 / #8.

4. An open curve profile rounding and chamfering macro programming method according to claim 1, wherein, In the step 4, the outer profile is outwardly offset by #13, the inner profile is inwardly offset by #13, the convex circular arc radius is added by #13, and the concave circular arc radius is subtracted by #13; when the outer profile is machined, the envelope line is outwardly offset by #13, so #13 is added; when the inner profile is inwardly offset, the envelope line is inwardly offset by #13, so #13 is subtracted; the convex circular arc is added by #13, and the concave circular arc is subtracted by #13, so that the polar radius in the step 1 can flexibly add or subtract the value of the parameter #13, and the macro programming of the parameter #13 with the tool path movement is realized.

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