A method for determining the position of a blade design shape in a machine tool

Abstract

The present application relates to the field of tool machining, and discloses a method for determining the position of a designed shape of a blade in a machine tool by detection, to solve the problem that the position of a structure on a blade relative to a blade slot does not conform to the design when the blade is used in the blade slot.

Description

Technical Field

[0001] This invention relates to the field of cutting tool processing, and more specifically to a method for determining the position of the cutting tool design shape in a machine tool. Background Technology

[0002] During use, inserts are mostly fixed in insert slots. The insert is positioned by three or more surfaces of the insert slot to constrain its six degrees of freedom, ensuring that the position of the cutting edge or a certain structure on the insert relative to the insert slot is consistent with the relative position of that structure and the insert slot as determined in the design. Taking the machining of indexable insert edges as an example, to meet the above requirements, existing technologies usually use a fixture that simulates the insert slot and positions the insert in the machine tool by clamping the insert. After fixing, the cutting edge is machined. This method requires the pre-design and manufacture of a special fixture for clamping the insert in the machine tool. Moreover, due to the large number of cutting edges of indexable inserts, machining one insert requires multiple clamping to machine each cutting edge separately, which easily introduces repeated positioning errors in this process and increases additional time costs.

[0003] To avoid this problem, some technologies do not use simulated insert grooves to assist in cutting edge machining. Instead, they directly clamp the insert onto the machine tool and perform cutting edge machining. One approach is to directly probe the positions of several edges of the insert to determine the insert center offset, thus treating the insert as a reference point relative to the design. Figure 1 This method involves machining the blade to a uniform shape. However, it fails to account for shape errors that occur during blade manufacturing, resulting in a discrepancy between the cutting edge and the design when the blade is clamped in the insert slot. Similarly, other structures on the blade, besides the cutting edge, also encounter the same problem when clamped in the insert slot. In some technical solutions, the blade is not removed after face grinding but is directly machined on the same machine tool for the cutting edge, chip breaker, and other structures to avoid repeated probing. However, this technique still does not consider the discrepancy between the surface formed after face grinding and the design, resulting in the cutting edge and other structures still being misaligned with the design when the machined blade is clamped in the insert slot. Summary of the Invention

[0004] The present invention aims to provide a method for determining the position of the blade design shape in a machine tool, so as to solve the problem in the prior art that the position of the structure on the blade relative to the blade slot does not match the design when the blade is used in the blade slot.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a method for determining the position of the blade design shape in a machine tool;

[0006] The blade:

[0007] There exists a positioning structure for limiting the movement of any point of the blade in a certain direction. This direction is called the axial positioning direction, the plane perpendicular to the axial positioning direction is called the axial plane, the positioning structure is called the axial positioning structure, and the surface that contacts the axial positioning structure and achieves the limiting effect is called the basic positioning surface.

[0008] Based on the axial positioning structure, the cutting tool has a positioning structure for any selected cutting edge that further restricts the movement of any point of the cutting tool in any direction perpendicular to the axial positioning direction. This direction is the main positioning direction, and this positioning structure is the main positioning structure. The main positioning structure contains two or more main positioning regions. Each main positioning region is a planar region that includes an independent main positioning point. The projection of the normal of the main positioning region into the axial plane is parallel to the main positioning direction.

[0009] Based on the axial positioning structure and the main positioning structure, the cutting tool has a positioning structure for any selected cutting edge to further restrict the translation of the cutting tool in a direction perpendicular to both the axial positioning direction and the main positioning direction, which is a secondary positioning direction; the positioning structure is a secondary positioning structure; the secondary positioning structure contains one or more secondary positioning regions, and the secondary positioning region is a planar region including a single secondary positioning point.

[0010] The machine tool is a three-axis or higher CNC machine tool;

[0011] The design shape is the shape that is determined during the design of the blade;

[0012] Determining the position of the cutting tool's designed shape within the machine tool through positioning point detection includes:

[0013] A. The selected positioning points are the main positioning point and the secondary positioning point on the blade;

[0014] B. Before probing the positioning point, determine the coordinates of the positioning point in the axis positioning direction, main positioning direction, and secondary positioning direction. The error of these coordinates must meet the requirement that during the positioning point probing process, probing any selected positioning point will not detect anything outside the positioning area where the selected positioning point is located.

[0015] C. Use a contact probe to detect the selected positioning point to obtain the point coordinates, and use the point coordinates as the precise coordinates of the selected positioning point; the point coordinates must be within the positioning area of ​​the selected positioning point;

[0016] D. Calculate the shape of the blade in the machine tool according to the precise coordinates of the detected positioning point, and calculate the position of any point on the shape of the blade in the machine tool coordinate system according to the position of the blade relative to the blade slot when positioning in the blade slot.

[0017] Preferably, step C includes:

[0018] E. Make the contact probe detect the selected positioning point along the detection line, wherein the detection line is the projection line of the normal of the surface where the selected positioning point is located in the axial plane.

[0019] F. Calculate the normal to the surface of the selected positioning point using the coordinates of all known positioning points. Calculate the error between the normal and the probe shape to obtain the coordinates of the detected point. Compensate for this error to obtain the precise coordinates of the selected positioning point.

[0020] Preferably, step C includes: using a contact probe to detect the selected positioning point along the detection line to obtain a point coordinate, which is considered to be the precise coordinate of the selected positioning point; the detection line is the normal to the surface where the selected positioning point is located; the point coordinate may have an error compared to the actual coordinate of the selected positioning point, but the point coordinate must be within the positioning area where the selected positioning point is located.

[0021] Preferably, for an indexable insert where each edge contains both a primary locating point and a secondary locating point, one of the primary locating points on each edge that is close to the secondary locating point on that edge can be taken at the secondary locating point. By replacing one primary locating point on each edge with a secondary locating point on the same edge, a simplified set of primary and secondary locating points can be obtained. This method helps to reduce the number of points to be detected, thereby increasing the processing speed.

[0022] Preferably, each positioning point exists within a positioning area, and the area of ​​the positioning area is the area of ​​a circle centered on the positioning point, which is less than one percent of the area of ​​the blade plane to which it belongs.

[0023] Preferably, two or more main positioning points on the blade are on unconnected straight lines.

[0024] Preferably, the blade has only one cutting edge, and two or more main positioning points are located on two unconnected straight lines, with different coordinates in the main positioning direction.

[0025] Preferably, when the blade has no center hole and the normals of the main positioning point or the secondary positioning point are not in the axial plane, the detection process for any positioning point includes steps E and F of step C.

[0026] Preferably, when the two main positioning points corresponding to the cutting edge of the blade are respectively on two planes where the normals intersect, and the plane where one main positioning point is located is perpendicular to the end face, and the plane where the other main positioning point is located forms an angle with the end face, the detection process for any positioning point adopts sub-steps E and F of step C.

[0027] The principle of this solution is as follows: The blade shape and the blade groove, which contacts the blade during use and performs the blade positioning function, are determined during the design phase. The positioning relationship of the blade on this blade groove is called the design positioning relationship, and the positioning points in the design positioning relationship are called design positioning points. Since the contact between the blade and the blade groove during positioning, whether surface contact or line contact, can be simplified as a point contact relationship existing in the contact area, and all degrees of freedom of the blade are constrained while satisfying the six-point positioning rule, the simplified contact relationship can be seen as the blade contacting the blade groove at the two main positioning points, one secondary positioning point, and one axial positioning structure mentioned above.

[0028] The shape of the manufactured blade inevitably differs from the designed shape. The blade with no machining error is defined as the designed blade, while the blade with actual error is defined as the actual blade.

[0029] Since the cutting edge groove remains unchanged, transforming the position of the designed cutting edge relative to the cutting edge groove into the coordinate system of the actual cutting edge groove yields the position of any point on the designed cutting edge relative to any point on the actual cutting edge. Furthermore, because the cutting edge groove in this transformation process can be simplified to a positioning point, the position of any point on the designed cutting edge in the machine tool coordinate system can be obtained by detecting the coordinates of the positioning point.

[0030] The advantages of this invention are:

[0031] This invention is applicable to inserts of different shapes, such as round inserts, equilateral triangular inserts, quadrilateral inserts, and other single-edged or multi-edged inserts. This invention ensures that when the actually manufactured insert and the designed insert are clamped into the insert slot, the cutting edge or chip breaker groove on the insert are positioned approximately identically to the insert slot, even if there are errors in the actual manufacturing process. Furthermore, this invention improves upon the method described in the prior art of positioning inserts in a machine tool using a fixture that simulates the insert slot, eliminating the need for pre-designing and manufacturing a special fixture for clamping inserts in the machine tool. It also reduces repetitive positioning errors and clamping time when machining cutting edges or chip breaker grooves with indexable inserts. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the indexable insert being positioned in the insert groove in Embodiment 1.

[0033] Figure 2 This is an explanatory diagram of the selected positioning section in Example 1.

[0034] Figure 3 This is an explanatory diagram of the positioning section to be detected in Example 1.

[0035] Figure 4 This is a schematic diagram showing the positions of several blades of the blade described in Embodiment 1.

[0036] Figure 5 This is a schematic diagram of the blade described in Example 2.

[0037] Figure 6 This is a schematic diagram of the blade described in Example 3.

[0038] Figure 7 This is a schematic diagram of the blade described in Example 4.

[0039] Figure 8 This is a schematic diagram of the blade described in Example 5.

[0040] Figure 9 This is a schematic diagram of a method for determining the position of the blade design shape in a machine tool as described in Embodiment 7.

[0041] Figure 10 , Figure 11 , Figure 12 This is a schematic diagram of the clamping method described in Example 8.

[0042] Figure 13 This is a schematic diagram of the blade described in Example 9.

[0043] Figure 14 , Figure 15 This is a cross-sectional view of the blade described in Example 9.

[0044] Figure 16 This is a schematic diagram of the blade clamping described in Example 9. Detailed Implementation

[0045] The following detailed description illustrates the specific implementation method:

[0046] The reference numerals in the accompanying drawings include: blade a, blade groove b, end face e, blade position one f, blade position two g, blade position three h, cutting edge one i, main positioning point one j, main positioning point two k, cutting edge two l, position five m, position six n, flat center o, and positioning block p.

[0047] Example 1: A method for determining the position of a cutting tool's design shape in a machine tool. In this example, using... Figure 1 The sharpening of an indexable equilateral triangular cutting tool is shown as an example.

[0048] Figure 1 In the figure, A and B are the two main positioning points of blade a in this positioning state, C is the secondary positioning point of blade a in this positioning state, 1 is a plane on blade groove b that fits with blade a, and 2 is a plane on blade groove b.

[0049] Figure 2 The blade in the middle is Figure 1 In the diagram, blade a is a, and α is the plane passing through the axis of blade a.

[0050] Most indexable inserts are positioned in insert groove b during use. Insert groove b refers to the commonly used groove for clamping indexable inserts. Insert groove b contacts insert a, constraining the six degrees of freedom of insert a. One or more surfaces on insert groove b are basic locating surfaces, which will... Figure 1 Even after being constrained by the mid-end face e, the blade a still possesses three degrees of freedom: rotation around the axial positioning direction and translation in two mutually perpendicular directions within the axial plane. The remaining three degrees of freedom of blade a are constrained by the plane on the blade groove b. For example, after pressing the blade a against surface 1 on the blade groove b with an eccentric screw, surface 1 contacts the blade a. The angular direction of the blade a is determined by the surface contact. The principal positioning points on the blade a can be any two points that are far apart on the surface in contact with surface 1. The blade a is constrained by the points on the blade groove b that contact these two points, losing its rotational degree of freedom around the axial positioning direction and its translational degree of freedom in the direction perpendicular to surface 1. When surface 2 of the blade groove b contacts the blade a, since the angle between surface 1 and surface 2 of the blade groove b is slightly smaller than the included angle between the two surfaces of the blade a that are in contact with surface 1 and surface 2, surface 2 of the blade groove b and the blade a are in line contact. The secondary positioning point on the blade a can be any point on the line segment of this line contact. The point on surface 2 of the blade groove b that contacts this secondary positioning point restricts the degree of freedom of the blade a in translation perpendicular to surface 2. At this time, the degree of freedom of the blade a is completely constrained. Simplifying the constraints of surface 1 and surface 2, and selecting the primary positioning point as... Figure 1 Points A and B are shown in the diagram, and point C is the secondary positioning point. All three positioning points A, B, and C are on the same plane parallel to the axis plane.

[0051] To grind the cutting edge of the indexable equilateral triangular insert in this embodiment, the following steps are performed.

[0052] (1) First, clamp the cutting tool a on the headstock rotary axis of the five-axis machine tool, so that... Figure 1The middle end face e makes surface contact with one face on the fixture. The blade a is secured by screws tightened at the center hole of the blade a. Based on the blade shape parameters, fixture and screw parameters, and the relative positions of the blade a with the fixture and screw, we can obtain the coordinates of the blade a in the machine tool coordinate system. This means that during the positioning point detection process, detecting any selected positioning point will not detect anything outside the positioning area where the selected positioning point is located. The coordinates of the blade a in the machine tool coordinate system at this time are called the blade position f. Besides the clamping method described in this example, there are many other methods for fixing the blade a, such as using a flat or conical center for clamping, using a fixture with two surfaces constraining four degrees of freedom for positioning and then fixing with screws, using a fixture constraining all degrees of freedom for positioning and then clamping with a center, or using a fixture constraining all degrees of freedom and then fixing the blade by thermal expansion, etc. Therefore, it cannot be considered that this patent only has one clamping method.

[0053] (2) Based on the current blade position f of blade a, take the blade section located in the axial plane α parallel to the end face e. This blade section is called the positioning section, such as... Figure 3 As shown. Because the planes containing the two main positioning points and the line containing the one secondary positioning point all intersect with the positioning section, the selected positioning section can be considered as a two-dimensional plane containing all the simplified positioning points of the blade a. Each of the simplified positioning points exists within a positioning region, and the area of ​​the positioning region is the area of ​​a circle centered on the positioning point above it, which is less than one percent of the area of ​​the blade plane to which it belongs.

[0054] (3) Detection and positioning point stage, such as Figure 3 As shown, since each edge of the indexable insert contains both a primary positioning point and a secondary positioning point, the primary positioning point on each edge that is close to the secondary positioning point can be taken at that secondary positioning point, thus saving unnecessary probing. Therefore, by replacing one primary positioning point on each edge with a secondary positioning point on the same edge, and then selecting, we can obtain positioning points A to F. These points are the simplified primary and secondary positioning points.

[0055] (4) Use Figure 4 The coordinates of points C and D at position f of the blade are used to detect points C and D. The detection method in this embodiment is as follows: a point is selected by detecting a plane perpendicular to the location of the positioning point. If the point to be detected is a positioning point, the coordinates of the detected point must be within the positioning area of ​​the positioning point. This detection method is also a general method for detecting the coordinates of other points in this embodiment. After obtaining the detection coordinates of points C and D, the actual angle of the side containing the detected points C and D is calculated. For detailed explanation, this step is described using... Figure 4 For example, in Figure 4In the diagram, points 1 and 3 represent points C and D in blade position 1f, respectively, while points 2 and 4 are the coordinates of points C and D obtained from the detection. The position of the straight line formed by points 2 and 4 is calculated using these coordinates. The coordinates of the entire blade a in blade position 1f are moved so that point 3 in blade position 1f coincides with point 4. Then, the coordinates of the entire blade a in blade position 1f are rotated around point 1 by an angle, which is the angle between the straight line formed by points 1 and 3 and the straight line formed by points 2 and 4. Through this rotation, point 1 in blade position 1f is moved to the straight line containing points 2 and 4, forming... Figure 4 The blade position 2g is the coordinate of the blade shape in the machine tool after detection and correction.

[0056] (5) To obtain the approximate location of the remaining positioning points, probe any point on the straight line containing AB or EF. For example, if the probed point is point 6 and the detected coordinates are point 7, then move the blade position g parallel to the straight line containing 2 and 4, so that the edge containing point 6 moves to a point on it with coordinates of point 7, forming... Figure 4 The blade position 3h in the figure refers to the coordinates of the blade shape in the machine tool after it has been corrected by detection.

[0057] (6) Calculate the precise coordinates of points C and D. Because the actual angle detected in (4) caused the plane of the vertical positioning point to be not satisfied during detection, the detection coordinates of points C and D obtained before were incorrect. Therefore, after calculating the error with the actual angle, the error was corrected to obtain the precise coordinates of points C and D. The positioning points on the two straight sides of AB and EF in the positioning section, except for the positioning points detected in (5), were detected respectively. The precise coordinates of all remaining positioning points were obtained. The AB side in the blade position three h was moved to the position containing the coordinates of the detected points A and B. The EF side in the blade position three h was moved to the position containing the coordinates of the detected points E and F. At this time, the AB side and EF side obtained by detection were used to update the coordinates of the blade shape in the blade position three h, and the final blade shape in the machine tool coordinate system was obtained. Blade position four.

[0058] (7) Finally, grinding begins. The method used in this embodiment to determine the position of the cutting tool design shape in the machine tool is as follows:

[0059] (a) Position the blade shape in blade position four within the blade groove b determined during the design. Using blade groove b as a reference, since the position of the design shape relative to blade groove b is known, the position of the design shape relative to the blade shape in blade position four is also known.

[0060] (b) Since the shape of the blade in blade position four is known in the machine tool coordinate system, the position of the design shape relative to blade position four in the machine tool coordinate system is also known.

[0061] (c) Grind the cutting edge according to the known design shape and its position in the machine tool coordinate system. Complete the grinding of the indexable insert.

[0062] In Example 1, (4) to (7) describe how all cutting edges are ground only after all the main and secondary positioning points have been detected and the blade position is obtained. However, this is only one specific implementation method of this patent. In actual operation, it is possible to choose to grind the cutting edge according to the blade design shape after all the main and secondary positioning points corresponding to one or two cutting edges have been detected.

[0063] In Example 1, (4) to (6) are simplified by replacing one of the main positioning points with a secondary positioning point. However, this is only one case. In actual operation, this step may not be simplified. Instead, all main and secondary positioning points may be detected, or not only the main and secondary positioning points may be detected, but also other points on the blade may be detected to reduce errors.

[0064] In Example 1, (4) to (7) describe how all the main and secondary positioning points are detected before the blade position is obtained, and then all cutting edges are ground. Similarly, regardless of the number of cutting edges, whether they are rhomboid blades, round blades, square blades, or non-standard blades of various shapes, as long as they meet the characteristics of having the axial positioning structure, main positioning structure, and secondary positioning structure of the blade, this solution can detect the positioning points on them and obtain the positional relationship with the designed shape.

[0065] Example 2, as Figure 5 As shown, this embodiment uses a different blade than that in Embodiment 1. Figure 5 The main positioning point of the blade and Figure 1 The difference is that the two main positioning points are on unconnected straight lines; the specific implementation method for machining the cutting edge of this insert can be the same as in Example 1.

[0066] Example 3, as Figure 6 As shown, in this embodiment, only one cutting edge 1 of the insert can be used, and the corresponding main positioning points are on two unconnected straight line sides, and the coordinates of the two main positioning points are different in the main positioning direction. The specific implementation method for machining the cutting edge of this insert can be the same as in Embodiment 1.

[0067] Example 4, as Figure 7As shown, the insert used in this embodiment does not have a center hole, and regardless of which face serves as the axial positioning structure, the normal to either the primary or secondary positioning point is not within the axial plane. Therefore, for the requirement of detecting the face where the vertical positioning point is located, some machine tools find it difficult to meet this requirement. Thus, although the shape of the insert used in this embodiment can still be detected using the detection method described in Embodiment 1, on machine tools where this is not possible, the process of detecting any point when machining the cutting edge with this type of insert is as follows:

[0068] (1) Make the contact probe detect the selected positioning point along the detection line, wherein the detection line is the projection line of the normal of the surface where the selected positioning point is located in the axial plane.

[0069] (2) Calculate the normal of the surface where the selected positioning point is located by using the coordinates of all known positioning points. Calculate the error of the detected coordinates based on the normal and the shape of the probe. Compensate for the error to obtain the accurate coordinates of the selected positioning point.

[0070] In addition to detection, since the blade in this embodiment does not have a center hole, the screws used in Embodiment 1 cannot be used for fixing in this example. Therefore, a flat tip can be used for fixing in this embodiment.

[0071] The specific implementation method for machining the cutting edge of this blade can be the same as in Example 1.

[0072] Example 5, as Figure 8 As shown, the cutting edge of the blade used in this embodiment, i.e., the main positioning point corresponding to the cutting edge i, is on two planes where the normals intersect. The plane where the main positioning point j is located is perpendicular to the end face, and the plane where the main positioning point k is located forms a 145-degree angle with the end face. Because the blade in this embodiment is similar to the blade in embodiment 4, it is difficult to meet the requirement of probing the plane where the positioning point is located perpendicularly. Therefore, the blade in this embodiment also probes any point when machining the cutting edge as follows: (1) Make the contact probe probe along the probe line to select the positioning point. The probe line is the projection line of the normal of the plane where the selected positioning point is located in the axial plane.

[0073] (2) Calculate the normal of the surface where the selected positioning point is located by using the coordinates of all known positioning points. Calculate the error of the detected coordinates based on the normal and the shape of the probe. Compensate for the error to obtain the accurate coordinates of the selected positioning point.

[0074] The specific implementation method for machining the cutting edge of this blade can be the same as in Example 1.

[0075] Example 6. The difference between this example and Example 1 is that if the six degrees of freedom of the blade are restricted by a fixture with known coordinates or other methods before fixing the blade, then the rough coordinates of all the positioning points are already known. Steps (4), (5), and (6) can be removed and replaced with: detecting the two positioning points on the straight sides of AB, CD, and EF on the positioning section respectively, obtaining the precise coordinates of all positioning points, moving the AB side in blade position three h to a position containing the coordinates of the detected points A and B, moving the CD side in blade position three h to a position containing the coordinates of the detected points C and D, and moving the EF side in blade position three h to a position containing the coordinates of the detected points E and F. At this time, the AB, CD, and EF sides obtained by detection are used to update the coordinates of the blade shape in blade position three h, and the final position of the blade shape in the machine tool coordinate system is blade position four.

[0076] Example 7: The difference between this example and Example 1 is that if the method described in step (7) is not used, and the position of the blade design shape in the machine tool needs to be determined, then... Figure 9 In the middle, the blade is two l Figure 1 The blade 3 shown in the image. Figure 9 Midpoint 1 and point 2 are the precise coordinates of the two main positioning points corresponding to the actual detection when using cutting edge 2l. The blade design shape is placed in the machine tool coordinate system according to the precise coordinates of points 1 and 2, and the position 5m of the design shape is obtained. Point 5 is the coordinate position of the secondary positioning point corresponding to the use of cutting edge 2l when the blade design shape is in position 5m. However, due to manufacturing errors, the precise coordinates of the secondary positioning point actually detected in Example 1 are point 6. Therefore, the position 5m of the design shape is translated along the straight line where points 1 and 2 are located, so that the side of the straight line where midpoint 5 is located in position 5m is moved to a position containing point 6. At this time, the position 6n of the blade design shape is the position of the blade design shape in the machine tool, and the positions of the two main positioning points in position 6n also become the positions of points 3 and 4.

[0077] Example 8: In this example, the blade clamping method described in Example 1 is changed to using a rotatable flat center for positioning and clamping, such as... Figure 10 As shown, the blade is clamped by flat tips on both sides, and fixed by friction and pressure from the tips. A positioning block p is located below the blade. Figure 11 , Figure 12As shown, the positioning block p can rotate synchronously with the flat center o. In use, the right-side flat center o and positioning block p are fixed to the machine tool's rotating axis, together positioning the cutting tool. Because the positioning block p and the cutting tool are of the same length, the operator or robot can easily ensure a small positional coordinate error when positioning the cutting tool. At this time, by using the coordinates of the positioning block p within the machine tool, a relatively accurate coordinate of the cutting tool within the machine tool can be obtained. Finally, by moving the left-right flat center o, the cutting tool is fixed inside the machine tool, and the cutting tool clamping is completed.

[0078] Example 9: In this example, to clarify the diversity of application directions and specific application methods of this patent, the following is used: Figure 13 The chip removal groove test of the non-standard blade shown is illustrated as an example.

[0079] Figure 13 In this type of blade, there is only one pair of primary and secondary positioning points: primary positioning points A and B, and secondary positioning point C. The plane containing points A and B acts as the primary positioning structure, fitting flush with the blade groove plane when used in the blade groove. Similarly, the plane containing point C acts as the secondary positioning structure, fitting flush with the blade groove plane. A cross-section of the blade is obtained by drawing planes perpendicular to A and B, passing through A and B. Figure 14 and Figure 15 When selecting points A, B, and C, try to keep them as far away from the edge of the surface as possible. This will help prevent the location area from being detected during the probe. When selecting points A and B, also make sure they are as far apart as possible to reduce errors in calculation and detection.

[0080] To test the chip removal groove of the blade in this embodiment, the following steps are adopted.

[0081] (1) Use a flat-tipped tip to cut the blade. Figure 16 As shown in the clamping diagram, if manual clamping is used, the blade position may not be precisely positioned during clamping with the flat-topped tip, potentially introducing significant coordinate errors. In this case, a vision system or laser-assisted system can be used to detect the blade's position coordinates, obtaining a more accurate overall blade coordinate system. However, if a robotic arm is used for clamping, the blade's position can be precisely positioned before gripping, ensuring a relatively accurate blade position coordinate from gripping to clamping, thus eliminating the need for the vision system's position detection process.

[0082] (2) Using the blade position coordinates obtained in (1) as the initial blade position, a contact probe is used to detect and select a positioning point along the detection line. Then, the normal of the surface where the selected positioning point is located is calculated using the coordinates of all known positioning points. The error of the detected coordinates is calculated based on the normal and the shape of the probe. This error is compensated to obtain the accurate coordinates of the selected positioning point. First, the position coordinates of the secondary positioning point C are detected to obtain the detection coordinates of point C. Then, a point D that is on the same plane as point C but as far away as possible is detected to obtain the detection coordinates of point D. Finally, a point E that is on the same plane as both C and D but as far away as possible from both points is detected to obtain the detection coordinates of point E. A straight line 1 is fitted from points C, D, and E using the least squares method, weighted fitting, or other methods. This line 1 is compared with the straight line 2 where points C and D are located at the initial blade position. The error generated during detection is corrected based on the angle between straight line 1 and straight line 2 to obtain the accurate coordinates of C, D, and E.

[0083] (3) Following the principle described in (2), continue to obtain the accurate coordinates of points A and B.

[0084] (4) By using the accurate coordinates of A, B, C, D, and E, the edges where the initial blade position is located are corrected to the accurate position coordinates to obtain the accurate position of the blade as a whole.

[0085] (5) Finally, the chip removal groove is inspected. The blade plane 1 containing the blade design shapes A and B is aligned with the blade plane 2, where the accurate coordinates of points A and B are measured within the machine tool. The blade design shape is then moved along plane 2 until point C on the blade design shape coincides with point C on the accurate position of the blade as a whole. The position of the blade design shape in the machine tool is then obtained. By comparing the design shape with the accurate position of the blade, the chip removal groove inspection is completed. The mathematical calculations involved in the above examples are basic knowledge, and the methods are not limited to one; therefore, they are not detailed here. The above examples demonstrate and describe the basic principles, main features, and advantages of this invention. Common knowledge such as machine tool operation is not described in detail here, but belongs to the general technical knowledge known to those skilled in the art before the application date or priority date. Those skilled in the art should understand that this invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this invention. Various changes and modifications can be made without departing from the spirit and scope of this invention, and all such changes and modifications fall within the scope of this invention as claimed.

Claims

1. A method for determining the position of a cutting tool's design shape in a machine tool, characterized in that: The blade: There exists a positioning structure for limiting the movement of any point of the blade in a certain direction. This direction is called the axial positioning direction, the plane perpendicular to the axial positioning direction is called the axial plane, the positioning structure is called the axial positioning structure, and the surface that contacts the axial positioning structure and achieves the limiting effect is called the basic positioning surface. Based on the axial positioning structure, the cutting tool has a positioning structure for any selected cutting edge that further restricts the movement of any point of the cutting tool in any direction perpendicular to the axial positioning direction. This direction is the main positioning direction, and this positioning structure is the main positioning structure. The main positioning structure contains two or more main positioning regions. Each main positioning region is a planar region that includes an independent main positioning point. The projection of the normal of the main positioning region into the axial plane is parallel to the main positioning direction. Based on the axial positioning structure and the main positioning structure, the cutting tool has a positioning structure for any selected cutting edge to further restrict the translation of the cutting tool in a direction perpendicular to both the axial positioning direction and the main positioning direction, which is a secondary positioning direction; the positioning structure is a secondary positioning structure; the secondary positioning structure contains one or more secondary positioning regions, and the secondary positioning region is a planar region including a single secondary positioning point. The machine tool is a three-axis or higher CNC machine tool; The design shape is the shape that is determined during the design of the blade; Determining the position of the cutting tool's designed shape within the machine tool through positioning point detection includes: A. The selected positioning points are the main positioning point and the secondary positioning point on the blade; B. Before probing the positioning point, determine the coordinates of the positioning point in the axis positioning direction, main positioning direction, and secondary positioning direction. The error of these coordinates must meet the requirement that during the positioning point probing process, probing any selected positioning point will not detect anything outside the positioning area where the selected positioning point is located. C. Use a contact probe to detect the selected positioning point to obtain the point coordinates, and use the point coordinates as the precise coordinates of the selected positioning point; the point coordinates must be within the positioning area of ​​the selected positioning point; D. Calculate the shape of the blade in the machine tool according to the precise coordinates of the detected positioning point, and calculate the position of any point on the shape of the blade in the machine tool coordinate system according to the position of the blade relative to the blade slot when positioning in the blade slot.

2. The method for determining the position of a cutting tool design shape in a machine tool according to claim 1, characterized in that: Step C includes: E. Make the contact probe detect the selected positioning point along the detection line, wherein the detection line is the projection line of the normal of the surface where the selected positioning point is located in the axial plane. F. Calculate the normal to the surface of the selected positioning point using the coordinates of all known positioning points. Calculate the error between the normal and the probe shape to obtain the coordinates of the detected point. Compensate for this error to obtain the precise coordinates of the selected positioning point.

3. The method for determining the position of a cutting tool design shape in a machine tool according to claim 1, characterized in that: Step C includes: using a contact probe to detect and select a positioning point along a detection line to obtain a point coordinate, which is considered to be the precise coordinate of the selected positioning point; the detection line is the normal to the surface where the selected positioning point is located; the point coordinate may have an error compared to the actual coordinate of the selected positioning point, but the point coordinate must be within the positioning area where the selected positioning point is located.

4. The method for determining the position of a cutting tool design shape in a machine tool according to claim 1, characterized in that: For an indexable cutting tool whose edges contain both primary and secondary positioning points, one of the primary positioning points on each edge that is close to the secondary positioning point on that edge can be taken at that secondary positioning point. By replacing one primary positioning point on each edge with a secondary positioning point on the same edge, we can obtain all the simplified primary and secondary positioning points.

5. The method for determining the position of a cutting tool design shape in a machine tool according to claim 1, characterized in that: Each positioning point exists within a positioning area, and the area of ​​the positioning area is the area of ​​a circle centered on the positioning point, which is less than one percent of the area of ​​the blade plane to which it belongs.

6. The method for determining the position of a cutting tool design shape in a machine tool according to claim 1, characterized in that: The blade has two or more main positioning points on unconnected straight lines.

7. The method for determining the position of a cutting tool design shape in a machine tool according to claim 1, characterized in that: The blade has only one cutting edge, and two or more main positioning points are on unconnected straight lines, with different coordinates in the main positioning direction.

8. The method for determining the position of a cutting tool design shape in a machine tool according to claim 2, characterized in that: When the blade has no center hole and the normals of the main positioning point or the secondary positioning point are not in the axial plane, the detection process for any positioning point adopts sub-steps E and F of step C.

9. The method for determining the position of a cutting tool design shape in a machine tool according to claim 2, characterized in that: The two main positioning points corresponding to the cutting edge of the blade are respectively on two planes where the normals intersect. When the plane where one main positioning point is located is perpendicular to the end face and the plane where the other main positioning point is located forms an angle with the end face, the detection process for any positioning point adopts sub-steps E and F of step C.

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