Adaptive machining method for part deformation flat

Abstract

The present application relates to the technical field of mechanical manufacturing, and more particularly to a self-adaptive machining method for deformed plane of a part, comprising: selecting a plane on the other side of a reference plane and any coordinate plane in a three-dimensional coordinate system of a numerical control machine tool, and making the selected plane parallel to the coordinate plane and at least one coordinate axis in the reference plane and the coordinate plane parallel; selecting a deformed point in a deformed plane to be machined and abutting against a multi-plate die, constructing a first plane as a machining plane of a spindle of the machine tool; selecting four marker points on a top plane of the plate die, obtaining distances of the marker points from a reference plane on which a plane of the part before deformation is located as deformation amounts of the marker points; obtaining a rotation angle of the first plane relative to the reference plane based on the distances of the marker points on the solid plane and the deformation amounts; and completing correction of a position of the machine tool and machining of the plane to be machined based on the rotation angle of the first plane relative to the reference plane. The present application greatly simplifies a machining program, easily realizes positioning of a machining plane of a spindle of the machine tool, and improves positioning accuracy.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of metal material manufacturing, in particular to a self-adaptive machining method for a deformed plane of a part. BACKGROUND

[0002] Welded parts are often welded from a large number of raw material parts. In order to meet the assembly requirements, the welded parts need to be machined after welding. During the welding process, due to the welding and assembly of parts, the parts often deform after welding. In order to ensure the machining accuracy during the machining process, the position and direction of the parts need to be adjusted according to the actual deformation of the parts to meet the machining requirements of the parts. On the other hand, combined parts, especially combined parts of different materials, deform differently at different temperatures. When the temperature of the combined parts changes sharply, the surface of the combined parts will also deform, which makes it difficult to meet the machining and use requirements.

[0003] In the prior art, a common method is to correct the position of the part. Based on the machine tool coordinate system, the three-dimensional coordinates of the part are adjusted so that the position of the machined plane matches the predetermined machining area. However, this method has the following defects: the irregular deformed surface of the part makes it difficult to position the deformed surface of the part, and it is time-consuming and laborious to use precise optical instruments. Another common method is to correct the position of the machine tool spindle for part machining. Typically, a marker point is selected on the spindle, and the marker point coordinates in the machine tool coordinate system are used to position the spindle. However, this method also has the following problems: it is difficult to confirm the deformation amount of the deformed surface of the part, and the adjustment program based on the marker point coordinates on the spindle is complex. There is an urgent need for a high-efficiency, high-precision positioning, correction and machining method for the deformed plane of a part. SUMMARY

[0004] In view of the above analysis, the present application aims to provide a self-adaptive machining method for a deformed plane of a part to solve at least one of the problems of difficulty in confirming the deformation amount of the deformed surface of the part, low efficiency of part machining correction, and poor positioning accuracy in the prior art.

[0005] The main purpose of the present application is achieved by the following technical solutions:

[0006] The present application discloses a self-adaptive machining method for a deformed plane of a part, comprising:

[0007] The machined plane before deformation is taken as a reference plane, and a plane on the other side relative to the reference plane and any coordinate plane in the three-dimensional coordinate system of the numerical control machine tool are arranged in parallel. The part to be machined is rotated in the coordinate plane so that at least one coordinate axis in the reference plane and the coordinate plane is parallel. The coordinate axis parallel to the reference plane is the first coordinate axis, and the other coordinate axis in the coordinate plane is the second coordinate axis.

[0008] A flat mold of uniform thickness is selected, and its bottom plane is made to abut against the outer surface of the deformed surface to be processed. The deformation point in the deformed surface to be processed that abuts against the multi-flat mold is selected to construct the first plane. The first plane is used as the processing plane of the deformed surface to be processed on the machine tool spindle.

[0009] Four marker points are selected on the top plane of the flat mold. The distance between the marker points and the reference plane on which the part plane is located before deformation is obtained, which is used as the deformation amount of the marker points. The marker points should satisfy the following condition: any three marker points are not collinear.

[0010] Based on the distances of the four marker points on the solid plane and their distances relative to the reference plane, the rotation angle of the first plane relative to the reference plane is obtained. The rotation angle includes: the rotation angle α of the reference plane around the first coordinate axis and the rotation angle β of the reference plane around the second coordinate axis. After the reference plane rotates α around the first coordinate axis and β around the second coordinate axis in sequence, it coincides with the first plane.

[0011] Based on the rotation angle of the first plane relative to the reference plane, the rotation angle of the machine tool spindle around the coordinate axis after correction relative to the initial position is obtained; based on the rotation angle of the machine tool spindle around the coordinate axis, the correction of the machine tool position and the machining of the plane to be processed are completed; wherein, after the machine tool spindle rotates around the coordinate axis from its initial position, it coincides with the corrected position of the machine tool spindle.

[0012] Preferably, the selection of deformation points within the deformed plane to be processed that abut against the multi-plate mold includes: laying the plate mold flat on the outside of the deformed plane to be processed, and all deformation points that contact the bottom surface of the plate mold are the deformation points for constructing the first plane.

[0013] Preferably, the flat plate mold is a cuboid with uniform thickness and has a flat top surface and bottom surface.

[0014] Preferably, the selection of the first and second coordinate axes includes the following steps:

[0015] Select a plane on the other side of the relatively deformed plane to be processed, and set it parallel to any coordinate plane;

[0016] The part to be processed is rotated in the coordinate plane such that the reference plane and at least one coordinate axis of the coordinate plane are parallel; the coordinate axis parallel to the reference plane is the first coordinate axis, and the other coordinate axis in the coordinate plane is the second coordinate axis.

[0017] Preferably, obtaining the distance between the marker point and the reference plane containing the part before deformation includes:

[0018] Based on the three-dimensional coordinate system of CNC machine tools, the coordinates of the marked points are obtained using the machine tool spindle and dial indicator;

[0019] The deformation of the marker point relative to the reference plane is obtained based on the coordinates of the marker point.

[0020] Preferably, the step of obtaining the coordinates of the marker point using the machine tool spindle and dial indicator includes:

[0021] Connect the fixed end of the dial indicator to the machine tool spindle, bring the measuring end of the dial indicator into contact with the first mark point and clear the reading to zero, and obtain the coordinates of the first mark point from the coordinate display window of the CNC machine tool.

[0022] Adjust the machine tool spindle until the measuring end of the dial indicator contacts the second mark point, and continue adjusting the machine tool spindle until the dial indicator reading is zero; obtain the coordinates of the second mark point from the CNC machine tool coordinate display window;

[0023] Following the method used to obtain the coordinates of the second marker point, the coordinates of the third and fourth marker points are obtained sequentially.

[0024] Preferably, obtaining the rotation angle of the first plane relative to the reference plane includes:

[0025] The rotation angle α of the reference plane around the first coordinate axis and the rotation angle β of the reference plane around the second coordinate axis are obtained based on the deformation of the marker points relative to the reference plane and the spacing of the marker points on the outer surface of the flat mold.

[0026] Preferably, the rotation angle α of the reference plane around the first coordinate axis satisfies:

[0027] α=-(arcsin((R1-T3) / d13)+arcsin((R2-R4) / d24)) / 2;

[0028] Where R1 is the deformation of the first mark point, R3 is the deformation of the third mark point, R2 is the deformation of the second mark point, and R4 is the deformation of the fourth mark point; d13 is the distance between the first mark point and the third mark point on the upper surface of the flat mold; d24 is the distance between the second mark point and the fourth mark point on the upper surface of the flat mold.

[0029] The reference plane rotates about the second coordinate axis by an angle β that satisfies:

[0030] β=-(arcsin((R1-R2) / d12)+arcsin(R3-R4) / d34)) / 2;

[0031] Wherein, R1 is the deformation of the first marker point, R3 is the deformation of the third marker point, R2 is the deformation of the second marker point, and R4 is the deformation of the fourth marker point; d12 is the distance between the first and second marker points on the upper surface of the flat mold; and d34 is the distance between the third and fourth marker points on the upper surface of the flat mold.

[0032] Preferably, with the y-axis as the first coordinate axis, the x-axis as the second coordinate axis, and the z-axis as the third coordinate axis, the rotation angle C of the machine tool spindle around the third coordinate axis and the rotation angle B of the machine tool spindle around the first coordinate axis satisfy:

[0033] B=arccos(y×sinα+z×cosβcosα-x×sinβcosα)

[0034]

[0035] γ is the rotation angle of the reference plane around the z-axis; x is the x-axis coordinate of the reference plane, y is the y-axis coordinate of the reference plane, and z is the z-axis coordinate of the reference plane.

[0036] Preferably, the step of obtaining the rotation angle of the machine tool spindle around the coordinate axis is obtained by the vector coordinates of the rotation angle α of the reference plane around the first coordinate axis and the angle β of the reference plane after rotation around the second coordinate axis, including:

[0037] The vector coordinates of the rotation angle of the first plane relative to the reference plane are obtained based on the rotation angle α of the reference plane around the first coordinate axis and the rotation angle β of the reference plane around the second coordinate axis.

[0038] Based on the rotation order of the machine tool spindle around different coordinate axes, obtain the expressions for the rotation angle of the machine tool spindle around the coordinate axis and the coordinates of the rotation vector of the machine tool spindle around the coordinate axis;

[0039] Based on the fact that the vector coordinates of the rotation angle of the first plane relative to the reference plane are the same as the rotation angle of the machine tool spindle, the expressions for the rotation angle of the machine tool spindle around the coordinate axis and the rotation angle of the first plane relative to the reference plane are obtained, and the rotation angle of the machine tool spindle around the coordinate axis is obtained from the rotation angle of the first plane relative to the reference plane.

[0040] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0041] (1) By setting the plane on the other side of the relatively deformed plane to be processed parallel to a coordinate plane, and making the reference plane and at least one coordinate axis in the coordinate plane parallel, the rotation of any plane movement in space corresponding to the three coordinate axes in the spatial coordinate system is simplified to rotation around two coordinate axes in the coordinate plane. Compared with the prior art, this invention greatly simplifies the calculation and deformation surface positioning procedure of the deformed plane to be processed.

[0042] (2) The present invention constructs a first plane by selecting the three points with the largest deformation in the deformed plane to be processed, and confirms the reference for the maximum deformation of the deformed plane to be processed; it realizes the uniformization of deformation points with different deformation on the deformed plane to be processed, and the machine tool spindle can be adjusted with reference to the first plane to realize the processing of the deformed plane to be processed with different deformation at each location; compared with the prior art, the present invention accurately determines the reference for the maximum deformation of the deformed plane to be processed by using the principle of three points coplanarity, avoids the dependence on precision instruments, and solves the problems of difficult deformation reference positioning and poor positioning accuracy in the prior art.

[0043] (3) The present invention utilizes a flat mold to fit and cover the outer surface of the deformed plane to be processed. Its bottom surface contacts at least three deformation points with the largest deformation in the deformed plane to be processed. The first plane is constructed at the position of its bottom surface as the processing plane of the machine tool spindle, thereby realizing the positioning of the processing surface of the machine tool spindle. Compared with the existing technology, which directly obtains the coordinates of the deformation points on the deformed plane to be processed, the present invention does not rely on precision optical instruments and can more easily realize the positioning of the processing surface of the machine tool spindle.

[0044] (4) This invention selects four marker points on the upper surface of the flat mold, and obtains the rotation angle of the first plane relative to the reference plane on the coordinate axes by the distance from the four marker points to the reference plane; and obtains the vector coordinates of the first plane based on the rotation angle; and obtains the rotation angle of the spindle correction on each coordinate axis based on the coincidence of the first plane with the corrected spindle machining plane; and adjusts the spindle position based on the spindle rotation angle to achieve correction. Compared with the prior art, this invention, by correcting the spindle position, corrects the machined parts, eliminates the interference of uncertainty in the deformation of the machined parts, solves the problem of difficulty in determining the reference when correcting the machined parts, and improves accuracy and correction efficiency.

[0045] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages may become apparent from the description or be learned by practicing the invention. The objects and other advantages of this invention can be realized and obtained through the embodiments described and the accompanying drawings, which are particularly pointed out. Attached Figure Description

[0046] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0047] Figure 1 This is a flowchart of an adaptive machining method for a part deformation plane according to one embodiment of the present invention;

[0048] Figure 2This is a schematic diagram showing the connection between a flat mold and the deformed plane to be processed in an adaptive machining method for a part deformation plane according to one embodiment of the present invention.

[0049] Figure 3 This is a schematic diagram illustrating an adaptive machining method for the deformation plane of a part according to one embodiment of the present invention.

[0050] Figure label:

[0051] Reference plane 301; deformed plane to be processed 302; flat mold 303; deformation point 304; marking point 305; first coordinate axis 401; second coordinate axis 402; third coordinate axis 403; machine tool spindle 501; machine tool spindle processing plane 502; spindle processing end 503. Detailed Implementation

[0052] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which constitute a part of the present invention and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0053] To clearly illustrate the technical solution of the present invention, the following technical terms are further defined:

[0054] This invention discloses a part to be processed with a deformed plane, which requires further processing of the deformed plane; the part to be processed includes the deformed plane and a plane on the other side of the deformed plane, and the plane to be processed before deformation is parallel to the plane.

[0055] This invention discloses an adaptive machining method for the deformation plane of a part, such as... Figure 1 As shown, it includes the following steps:

[0056] Step 1: Using the plane to be processed before deformation as the reference plane, select a plane on the other side of the reference plane and set it parallel to any coordinate plane in the three-dimensional coordinate system of the CNC machine tool. Rotate the part to be processed in the coordinate plane so that the reference plane and at least one coordinate axis in the coordinate plane are parallel; wherein, the coordinate axis parallel to the reference plane is the first coordinate axis, and the other coordinate axis in the coordinate plane is the second coordinate axis.

[0057] It should be noted that any plane movement can be decomposed into the plane rotating around three coordinate axes in the spatial coordinate system. This invention is based on the rotation of the machine tool spindle around the coordinate axes of the CNC machine tool's three-dimensional coordinate system to achieve the machining position correction of the deformed plane. By selecting a plane on the other side of the relatively deformed plane to be machined and setting it parallel to any coordinate plane in the CNC machine tool's three-dimensional coordinate system, the program settings for machining the part to be machined can be simplified, and the deformation of the plane to be machined can be simplified to rotation around two coordinate axes of that coordinate plane, without needing to consider the rotation of the third coordinate axis. Compared with the prior art, the calculation is greatly simplified.

[0058] Furthermore, this invention uses the undeformed plane to be processed as a reference plane, a coordinate axis parallel to the reference plane as a first coordinate axis, and another coordinate axis within the coordinate plane as a second coordinate axis; the reference plane is rotated sequentially around the first and second coordinate axes to obtain the deformed plane to be processed. Compared with the prior art, this invention, by selecting the first and second coordinate axes, more easily determines the rotation sequence of the reference plane around the coordinate axes to obtain the deformed plane to be processed.

[0059] Step 2: Select a flat mold with uniform thickness, and make its bottom plane abut against the outer surface of the deformed surface to be processed. Select the deformation point in the deformed surface to be processed that abuts against the multi-flat mold to construct the first plane. Use the first plane as the processing plane of the deformed surface to be processed on the machine tool spindle.

[0060] It should be noted that before machining, the spindle machining plane needs to be set as the machining plane of the machining program; before the plane to be machined is deformed, it itself serves as the spindle machining plane; after the plane to be machined is deformed, the spindle machining plane and the deformed plane to be machined no longer match, and the position of the spindle machining plane needs to be adjusted so that the machining plane of the machine tool spindle coincides with the first plane.

[0061] It should be noted that, as Figure 2 As shown, after the plane to be processed is deformed, it deforms on the outer surface of the reference plane 301 to form the deformed plane to be processed 302. The deformed plane to be processed 302 is composed of multiple deformation points 304 with different deformation amounts relative to the reference plane.

[0062] Specifically, in order to select the deformation point with the largest deformation relative to the reference plane before deformation, a flat mold 303 with a uniform thickness and a bottom area not less than the deformed plane to be processed is laid flat on the outside of the deformed plane to be processed 302. All deformation points 304 that are in contact with the bottom surface of the flat mold 303 are the deformation points for constructing the first plane.

[0063] During implementation, a flat plate mold with uniform thickness is selected for the solid plane. The flat plate mold is laid flat on the outside of the deformed plane to be processed. All deformation points that contact the bottom surface of the flat plate mold are the deformation points for constructing the first plane. The flat plate mold is parallel to the first plane. The flat plate mold is a cuboid with uniform thickness and has a flat top surface and bottom surface. The top surface and bottom surface are parallel. The bottom surface naturally lies on the outer surface of the deformed plane to be processed under the action of gravity. At this time, the first plane is the bottom surface of the flat plate mold 303.

[0064] It should be noted that at least three deformation points with the largest deformation in the deformed surface to be processed are in contact with the bottom surface of the flat mold. A first plane is constructed based on these deformation points to achieve uniform processing of deformation points with different deformation amounts on the deformed surface to be processed. The machine tool spindle can be adjusted with reference to the first plane to achieve processing of the deformed surface to be processed with different deformation amounts in various places.

[0065] Step 3: Select four marker points on the top plane of the flat mold, and obtain the distance between the marker points and the reference plane on which the part plane is located before deformation, as the deformation amount of the marker points; wherein, the marker points should satisfy the following: any three marker points are not collinear.

[0066] Specifically, in the three-dimensional coordinate system of the CNC machine tool, the coordinates of the marker points are obtained, and based on the coordinates of the marker points and the equation of the reference plane, the distances of each marker point on the deformation plane relative to the reference plane are obtained.

[0067] Specifically, such as Figure 2 As shown, a mark point 305 is selected on the upper surface of the flat mold 303. Based on the three-dimensional coordinate system of the CNC machine tool, the coordinates of the mark point are obtained using the machine tool spindle and dial indicator.

[0068] During implementation, a dial indicator is connected to the end of the machine tool spindle. The dial indicator pointer is brought into contact with the first mark point and the reading is cleared to zero. The coordinates of the first mark point are obtained from the CNC machine tool coordinate system. The dial indicator pointer is then brought into contact with the second, third, and fourth mark points in sequence. The dial indicator reading is adjusted to zero and the coordinates of the corresponding mark points are obtained from the CNC machine tool coordinate system.

[0069] Specifically, using geometric knowledge, the distances of each marked point on the deformable plane relative to the reference plane can be obtained from the coordinates of the marked points and the equation of the reference plane.

[0070] During implementation, based on the undeformed planes that are parallel to the coordinate planes containing the first and second coordinate axes as selected above, the workpiece to be processed is fixed in the direction of the undeformed plane parallel to the coordinate planes containing the first and second coordinate axes. The equation of the reference plane in the machine tool coordinate system is obtained from the three-dimensional graphic of the workpiece under the ideal state of no deformation and the positional relationship of the reference plane relative to the undeformed plane.

[0071] It should be noted that the three-dimensional graphic of the part to be processed in the ideal state without deformation is the three-dimensional graphic of the part to be processed in the original design. Those skilled in the art will pre-draw the three-dimensional graphic of the part to be processed before processing and specify the design dimensions and other parameters of the part to be processed, but do not consider factors such as processing deformation and processing error.

[0072] Step 4: Based on the distances of the four marker points on the entity plane and their distances relative to the reference plane, obtain the rotation angle of the first plane relative to the reference plane; wherein, the rotation angle includes: the rotation angle α of the reference plane around the first coordinate axis and the rotation angle β of the reference plane around the second coordinate axis; after the reference plane rotates α around the first coordinate axis and β around the second coordinate axis in sequence, it coincides with the first plane.

[0073] It should be noted that any planar movement can be decomposed into rotation around three coordinate axes in the spatial coordinate system. The selected undeformed plane is set parallel to the coordinate plane containing the first and second coordinate axes. The coordinate axis outside the first and second coordinate axes is taken as the third coordinate axis, which is perpendicular to the coordinate plane containing the first and second coordinate axes. No matter how the reference plane rotates around the third coordinate axis, its projection on the coordinate plane containing the first and second coordinate axes remains unchanged. The distance (deformation) of each point on the reference plane relative to the coordinate plane containing the first and second coordinate axes remains unchanged. Therefore, the rotation of the reference plane into the first plane does not require consideration of rotation around the third coordinate axis.

[0074] Meanwhile, the deformation of the plane to be processed after deformation is a micro-deformation, which will not change the state of the first plane being approximately parallel to the first coordinate axis. The order of rotation of the reference plane around the first and second coordinate axes will affect the position of the changed reference plane: Since the reference plane is parallel to the first coordinate axis but not parallel to the second coordinate axis, after the reference plane rotates around the first coordinate axis, it can maintain the intermediate state of the reference plane being parallel to the first coordinate axis, and further rotate around the second coordinate axis to coincide with the first plane, so the first plane is still in a state of approximately parallel to the first coordinate axis; however, if the reference plane rotates around the second coordinate axis first, it cannot maintain the intermediate state of the reference plane being parallel to the first coordinate axis, and further rotate around the first coordinate axis to obtain the final plane, so the final plane does not satisfy the state of approximately parallel to the first coordinate axis.

[0075] Specifically, the four marker points are numbered in clockwise or counterclockwise order as: first marker point, second marker point, third marker point, and fourth marker point, where the first marker point is the marker point with the largest deformation.

[0076] Specifically, in order to take into account the different deformation amounts corresponding to different marker points, the average value of the rotation angles between marker points around the first and second coordinate axes is calculated.

[0077] During implementation, the rotation angle of the reference plane around the second coordinate axis is obtained by taking the average of the rotation angle of the first marker point relative to the third marker point around the first coordinate axis and the rotation angle of the second marker point relative to the fourth marker point around the first coordinate axis; the rotation angle of the reference plane around the second coordinate axis is obtained by taking the average of the rotation angle of the second marker point relative to the first marker point around the second coordinate axis and the rotation angle of the third marker point relative to the first marker point around the second coordinate axis.

[0078] It should be noted that the rotation of the reference plane can be viewed as multiple sets of two-point lines between the first and fourth marker points rotating in different directions around the first and second coordinate axes. Specifically, when rotating around the first coordinate axis, the lines connecting the first and third marker points and the second and fourth marker points are selected to rotate relative to the reference plane around the first coordinate axis, and the average of the rotation results of the two sets of lines is taken as the reference plane rotation angle in that rotation direction. Similarly, when rotating around the second coordinate axis, the lines connecting the first and second marker points and the third and fourth marker points are selected to rotate relative to the reference plane around the second coordinate axis, and the average of the rotation results of the two sets of lines is taken as the reference plane rotation angle in that rotation direction.

[0079] Step 5: Based on the rotation angle of the first plane relative to the reference plane, obtain the rotation angle of the machine tool spindle around the coordinate axis after correction relative to the initial position; based on the rotation angle of the machine tool spindle around the coordinate axis, complete the correction of the machine tool position and the machining of the plane to be processed; wherein, after the machine tool spindle rotates around the coordinate axis from its initial position, it coincides with the corrected position of the machine tool spindle.

[0080] Specifically, the vector coordinates of the rotation angle of the first plane relative to the reference plane are the same as the vector coordinates of the rotation angle of the machine tool spindle around the coordinate axis.

[0081] It should be noted that the initial position of the machine tool spindle is the position of the machine tool spindle before the deformation of the plane to be machined; the rotation angle of the machine tool spindle around the coordinate axis is the deformation of the plane to be deformed. The machine tool spindle needs to be adjusted to match the plane to be machined after the deformation, so that the machine tool spindle machining plane coincides with the first plane.

[0082] Specifically, such as Figure 3 As shown, the rotation angle of the machine tool spindle includes: rotation angle B around the first coordinate axis 401 and rotation angle C around the third coordinate axis 403 from the initial position of the machine tool spindle. In practice, after the initial position of the machine tool spindle rotates by B around the first coordinate axis 401 and then by C around the third coordinate axis 403, it coincides with the correction position of the machine tool spindle.

[0083] It should be noted that in the three-dimensional coordinate system of a CNC machine tool, the arbitrary movement of the machining plane of the machine tool spindle can be decomposed into rotation around the three coordinate axes in the spatial coordinate system, setting the machining plane before parallel deformation at the initial position of the machine tool spindle, and setting the machining plane after parallel deformation at the corrected position of the machine tool spindle; such as Figure 3 As shown, on the one hand, in order to ensure that the machine tool spindle correction position is parallel to the deformed surface to be machined, the initial position adjustment of the machine tool spindle needs to prioritize the synchronous rotation of the reference plane around the first coordinate axis 401; on the other hand, when rotating around the second coordinate axis, the machining plane of the machine tool spindle makes an approximate translation on the first coordinate axis within a small range, and the reference plane is parallel to the first coordinate axis. Therefore, under this rotation direction, the displacement change of the machining plane of the machine tool spindle relative to the reference plane is not significant. Therefore, in order to adapt to the deformed surface to be machined, the position adjustment of the machine tool spindle does not include rotation around the second coordinate axis 402.

[0084] Specifically, the initial position setting of the machine tool spindle includes: based on the coordinates of the plane to be machined before deformation in the CNC machine tool coordinate system, the CNC machine tool control program controls the movement of the machine tool spindle to complete the initial position setting.

[0085] During implementation, the image of the part to be processed is input into the CNC machine tool control program, and the initial position coordinates of the spindle are set based on the coordinates of the plane to be processed before deformation; further, the CNC machine tool control program controls the machine tool spindle to the initial position.

[0086] Specifically, the rotation angle of the first plane relative to the reference plane and the rotation angle of the machine tool spindle are both represented by vector coordinates, satisfying: x1”=x2”, y1”=y2”, z1”=z2”, where x1”, y1”, z1” are the vector coordinates of the rotation angle of the first plane relative to the reference plane, and x2”, y2”, z2” are the vector coordinates of the rotation angle of the machine tool spindle, where x1” is the vector coordinate of the rotation angle around the first coordinate axis, y1” is the vector coordinate of the rotation angle around the second coordinate axis, z1” is the vector coordinate of the rotation angle around the third coordinate axis, x2” is the vector coordinate of the rotation angle around the first coordinate axis, y2” is the vector coordinate of the rotation angle around the second coordinate axis, and z2” is the vector coordinate of the rotation angle around the third coordinate axis.

[0087] Compared with the prior art, the present invention simplifies the rotation of any plane in space corresponding to the movement of three coordinate axes in the spatial coordinate system to a rotation of two coordinate axes in the coordinate plane by setting the plane on the other side of the relatively deformed plane to be processed parallel to a coordinate plane, and making the reference plane and at least one coordinate axis in the coordinate plane parallel, thereby greatly simplifying the calculation and deformation surface positioning procedure of the deformed plane to be processed compared with the prior art.

[0088] On the other hand, this invention constructs a first plane by selecting the three points with the largest deformation in the deformed plane to be processed, thus confirming the reference for the maximum deformation of the deformed plane to be processed. This achieves the homogenization of deformation points with different deformation amounts on the deformed plane to be processed. By adjusting the machine tool spindle with reference to the first plane, the deformed plane to be processed with different deformation amounts at various locations can be processed. Compared with the prior art, this invention accurately determines the reference for the maximum deformation of the deformed plane to be processed by utilizing the principle of three points being coplanar, avoiding dependence on precision instruments and solving the problems of difficult deformation reference positioning and poor positioning accuracy in the prior art.

[0089] In addition, this invention utilizes a flat mold to fit and cover the outer surface of the deformed plane to be processed. Its bottom surface contacts at least three deformation points with the largest deformation in the deformed plane to be processed. A first plane is constructed at the location of its bottom surface as the processing plane of the machine tool spindle, thereby realizing the positioning of the machining surface of the machine tool spindle. Compared with the existing technology that directly obtains the coordinates of the deformation points on the deformed plane to be processed, this invention does not rely on precision optical instruments and more easily realizes the positioning of the machining surface of the machine tool spindle.

[0090] In addition, this invention selects four marker points on the upper surface of the flat mold, and obtains the rotation angle of the first plane relative to the reference plane on the coordinate axes based on the distances from the four marker points to the reference plane; it then obtains the vector coordinates of the first plane based on this rotation angle, and obtains the rotation angle of the spindle correction on each coordinate axis based on the coincidence of the first plane with the corrected spindle machining plane; and adjusts the spindle position based on the spindle rotation angle to achieve correction. Compared with the prior art, this invention, by correcting the spindle position, corrects the machined parts, eliminates the interference of uncertainties in the deformation of the machined parts, solves the problem of difficulty in determining the reference during the correction of machined parts, and improves accuracy and correction efficiency.

[0091] Specifically, the method for determining the first and second coordinate axes in step 1 includes the following steps:

[0092] S101: Select a plane on the other side of the relatively deformed plane to be processed, and set it to be parallel to any coordinate plane;

[0093] S102: Rotate the part to be processed in the above coordinate plane so that the reference plane and at least one coordinate axis of the coordinate plane are parallel; the coordinate axis parallel to the reference plane is the first coordinate axis, and the other coordinate axis in the coordinate plane is the second coordinate axis.

[0094] It should be noted that when both coordinate axes in the reference plane and the coordinate plane parallel to the undeformed plane are parallel, the coordinate axis parallel to the reference plane can be arbitrarily chosen as the first coordinate axis.

[0095] Specifically, step 3, obtaining the distance between the marker point and the reference plane containing the part before deformation, includes:

[0096] S301: Based on the three-dimensional coordinate system of CNC machine tools, the coordinates of the marked points are obtained using the machine tool spindle and dial indicator;

[0097] Specifically, it includes the following steps:

[0098] S3011: Connect the fixed end of the dial indicator to the machine tool spindle, bring the measuring end of the dial indicator into contact with the first mark point and clear the reading to zero, and obtain the coordinates (X1, Y1, Z1) of the first mark point from the CNC machine tool coordinate display window; where X1, Y1, and Z1 are the x-axis, y-axis, and z-axis coordinates of the first mark point in the machine tool coordinate system, respectively.

[0099] S3012: Adjust the machine tool spindle until the measuring end of the dial indicator contacts the second mark point, and continue adjusting the machine tool spindle until the dial indicator reading is zero; obtain the coordinates (X2, Y2, Z2) of the second mark point from the CNC machine tool coordinate display window; where X2, Y2, and Z2 are the x-axis, y-axis, and z-axis coordinates of the second mark point in the machine tool coordinate system, respectively;

[0100] S3013: Obtain the coordinates of the third and fourth marker points in sequence according to the above steps.

[0101] S302: Obtain the deformation of the marker point relative to the reference plane based on the coordinates of the marker point;

[0102] Specifically, using the method of calculating the distance from a point to a plane in geometry, the distance between the marker point and the plane is calculated using the spatial coordinates of the marker point and the plane equation of the reference plane. This distance is used as the deformation of the corresponding marker point relative to the reference plane.

[0103] Specifically, obtaining the equation of the reference plane includes the following steps:

[0104] S3021: Based on the undeformed planes that are parallel to the coordinate planes containing the first and second coordinate axes as selected above, fix the part to be processed in the direction of the undeformed plane parallel to the coordinate planes containing the first and second coordinate axes.

[0105] S3022: Obtain the equation of the reference plane in the machine tool coordinate system from the positional relationship between the reference plane and the undeformed plane in the three-dimensional graphic of the part to be processed under the ideal state of no deformation.

[0106] Specifically, the equation of the reference plane in the three-dimensional graphic coordinate system under the ideal state of the part to be processed without deformation is: ax1+by1+cz1=0, where x1 is the x-axis coordinate, y1 is the y-axis coordinate, z1 is the z-axis coordinate, and a, b, and c are the corresponding coefficients.

[0107] The equation of the reference plane in the machine tool coordinate system satisfies: ax2 + by2 + cz2 = 0, where x2 is the x-axis coordinate, satisfying: x2 = x1 + δx; y2 is the y-axis coordinate, satisfying: y2 = y1 + δy; z2 is the z-axis coordinate, satisfying: z2 = z1 + δz; a, b, and c are the corresponding coefficients.

[0108] It should be noted that the machine tool coordinate system only undergoes a translation of the origin relative to the three-dimensional graphic coordinate system. The coefficients a, b, and c of the equation remain unchanged, and δx satisfies: δx = X0; δy satisfies: δx = Y0; δz satisfies: δz = Z0; where X0, Y0, and Z0 are the coordinates of the origin of the three-dimensional graphic coordinate system in the machine tool coordinate system, respectively.

[0109] Step 4, obtaining the rotation angle of the first plane relative to the reference plane, includes:

[0110] The rotation angle α of the reference plane around the first coordinate axis and the rotation angle β of the reference plane around the second coordinate axis are obtained based on the deformation of the marker points relative to the reference plane and the spacing of the marker points on the outer surface of the flat mold.

[0111] Specifically, the rotation angle α of the reference plane around the first coordinate axis satisfies:

[0112] α=-(arcsin((R1-R3) / d13)+arcsin((R2-R4) / d24)) / 2;

[0113] Wherein, R1 is the deformation of the first marker point, R3 is the deformation of the third marker point, R2 is the deformation of the second marker point, and R4 is the deformation of the fourth marker point; d13 is the distance between the first and third marker points on the upper surface of the flat mold; and d24 is the distance between the second and fourth marker points on the upper surface of the flat mold.

[0114] Specifically, the rotation angle β of the reference plane around the second coordinate axis satisfies:

[0115] β=-(arcsin((R1-R2) / d12)+arcsin(R3-R4) / d34)) / 2;

[0116] Wherein, R1 is the deformation of the first marker point, R3 is the deformation of the third marker point, R2 is the deformation of the second marker point, and R4 is the deformation of the fourth marker point; d12 is the distance between the first and second marker points on the upper surface of the flat mold; and d34 is the distance between the third and fourth marker points on the upper surface of the flat mold.

[0117] Step 5 describes obtaining the rotation angle of the machine tool spindle around the coordinate axis, which is obtained from the vector coordinates after the reference plane rotates around the first coordinate axis by an angle α and the reference plane rotates around the second coordinate axis by an angle β.

[0118] Specifically, it includes the following steps:

[0119] S501: Obtain the vector coordinates of the rotation angle of the first plane relative to the reference plane based on the rotation angle α of the reference plane around the first coordinate axis and the rotation angle β of the reference plane around the second coordinate axis;

[0120] Specifically, this invention provides a formula for spatial vector transformation based on planar translation, showing the coordinate changes after rotation around the x, y, and z axes respectively:

[0121] After rotation around the z-axis, the vector coordinates satisfy:

[0122] x'=x cosγ-y sinγ

[0123] y'=x sinγ+y cosγ

[0124] z' = z;

[0125] After rotation around the x-axis, the vector coordinates satisfy:

[0126] y'=y cosα-z sinα

[0127] z'=y sinα+z cosα

[0128] x' = x;

[0129] After rotation around the y-axis, the vector coordinates satisfy:

[0130] z′=z cosβ-x sinβ

[0131] x′=z sinβ+x cosβ

[0132] y′=y;

[0133] Where γ is the rotation angle around the z-axis, x, y, and z are the vector coordinates of the reference plane on the x-axis, y-axis, and z-axis before rotation, respectively; and x', y', and z' are the vector coordinates of the reference plane on the x-axis, y-axis, and z-axis after rotation, respectively.

[0134] Furthermore, as an example, in the machine tool coordinate system, the first coordinate axis is the y-axis, the second coordinate axis is the x-axis, and the third coordinate axis is the z-axis; the reference plane of the part to be machined is rotated around the y-axis and then around the x-axis to obtain the vector coordinates of the first plane corresponding to the deformed plane to be machined:

[0135] x″1=z sinβ+x cosβ

[0136] y″1=y cosα-z cosβsinα+x sinβsinα

[0137] z″1=y sinα+z cosβcosα-x sinγcosα;

[0138] Where x1” is the x-axis coordinate of the first plane after the reference plane is rotated around the y-axis and then around the x-axis, y1” is the y-axis coordinate of the first plane after the reference plane is rotated around the y-axis and then around the x-axis, and z1” is the z-axis coordinate of the first plane after the reference plane is rotated around the y-axis and then around the x-axis.

[0139] S502: Based on the rotation sequence of the machine tool spindle around different coordinate axes, obtain the expressions for the rotation angle of the machine tool spindle around the coordinate axis and the coordinate vector coordinates of the machine tool spindle around the coordinate axis;

[0140] The machine tool spindle first rotates around the y-axis, then around the z-axis, to obtain the machine tool spindle machining plane vector coordinates:

[0141] x″2=sin B cos C

[0142] y2″=sin B sin C

[0143] z2″=cos B;

[0144] Where x2” represents the x-axis coordinate of the machine tool spindle machining plane after it rotates around the y-axis and then around the z-axis; y2” represents the y-axis coordinate of the machine tool spindle machining plane after it rotates around the y-axis and then around the z-axis; z2” represents the z-axis coordinate of the machine tool spindle machining plane after it rotates around the y-axis and then around the z-axis; B represents the rotation angle of the machine tool spindle around the y-axis; and C represents the rotation angle of the machine tool spindle around the z-axis.

[0145] S503: Based on the fact that the vector coordinates of the rotation angle of the first plane relative to the reference plane and the rotation angle of the machine tool spindle are the same, obtain the expression relationship between the rotation angle of the machine tool spindle around the coordinate axis and the rotation angle of the first plane relative to the reference plane; obtain the rotation angle of the machine tool spindle around the coordinate axis from the rotation angle of the first plane relative to the reference plane.

[0146] Specifically, the expressed relationships satisfy: x1”=x2”, y1”=y2”, z1”=z2”; the rotation angle B of the machine tool spindle around the z-axis and the rotation angle C of the machine tool spindle around the y-axis satisfy:

[0147] B=arccos(y×sinα+z×cosβcosα-x×sinβcosα)

[0148]

[0149] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A method of adaptive machining of a part deformation plane, characterized in that, The application relates to a method for correcting the position of a numerical control machine tool, and belongs to the technical field of numerical control machine tools. The method comprises the following steps: Selecting a plane on the other side of a reference plane of a plane to be processed before deformation and a coordinate plane in a three-dimensional coordinate system of the numerical control machine tool, and rotating the part to be processed in the coordinate plane so that at least one coordinate axis in the reference plane and the coordinate plane is parallel; wherein the coordinate axis parallel to the reference plane is a first coordinate axis, and the other coordinate axis in the coordinate plane is a second coordinate axis; Selecting a flat die with uniform thickness so that the bottom plane of the flat die is in abutment with the outer surface of the deformed plane to be processed, selecting a deformation point in the deformed plane to be processed in abutment with the flat die, and constructing a first plane; the first plane is used as the deformed plane to be processed on the machining plane of the machine tool spindle; the flat die is a cuboid with uniform thickness, and the bottom surface of the flat die is in contact with at least three deformation points with the largest deformation in the deformed plane to be processed; Selecting four marker points on the top plane of the flat die, obtaining the distance of the marker points relative to the reference plane of the plane of the part before deformation as the deformation amount of the marker points; wherein the marker points should satisfy that any three marker points are not collinear; selecting the marker points on the upper surface of the flat die, and obtaining the coordinates of the marker points based on the three-dimensional coordinate system of the numerical control machine tool by using the machine tool spindle and the dial gauge; the distance of the marker points relative to the reference plane is obtained by contact measurement of the machine tool spindle and the dial gauge; Based on the distance of the four marker points on the entity plane and the distance relative to the reference plane, the rotation angle of the first plane relative to the reference plane is obtained, wherein the rotation angle comprises a rotation angle alpha of the reference plane around the first coordinate axis and a rotation angle beta of the reference plane around the second coordinate axis; after the reference plane is sequentially rotated by alpha around the first coordinate axis and beta around the second coordinate axis, the reference plane coincides with the first plane; The method for obtaining the rotation angle of the first plane relative to the reference plane comprises: Based on the deformation amount of the marker points relative to the reference plane and the distance of the marker points on the outer surface of the flat die, the rotation angle alpha of the reference plane around the first coordinate axis and the rotation angle beta of the reference plane around the second coordinate axis are obtained; ； The rotation angle alpha of the reference plane around the first coordinate axis satisfies: Wherein R1 is the deformation amount of the first marker point, R3 is the deformation amount of the third marker point, R2 is the deformation amount of the second marker point, and R4 is the deformation amount of the fourth marker point; d13 is the distance between the first marker point and the third marker point on the upper surface of the flat die; d24 is the distance between the second marker point and the fourth marker point on the upper surface of the flat die; ； The rotation angle beta of the reference plane around the second coordinate axis satisfies: Wherein R1 is the deformation amount of the first marker point, R3 is the deformation amount of the third marker point, R2 is the deformation amount of the second marker point, and R4 is the deformation amount of the fourth marker point; d12 is the distance between the first marker point and the second marker point on the upper surface of the flat die; d34 is the distance between the third marker point and the fourth marker point on the upper surface of the flat die; Based on the rotation angle of the first plane relative to the reference plane, the rotation angle of the machine tool spindle around the coordinate axis relative to the initial position after correction is obtained; based on the rotation angle of the machine tool spindle around the coordinate axis, the correction of the position of the machine tool and the machining of the plane to be processed are completed; wherein the initial position of the machine tool spindle coincides with the corrected position of the machine tool spindle after the initial position of the machine tool spindle is rotated by the rotation angle around the coordinate axis.

2. The method of claim 1 wherein, The deformed deformation point abutting against the multi-plate mold in the selected deformed processing plane comprises: laying the plate mold on the outside of the deformed processing plane, and all the deformation points in contact with the bottom surface of the plate mold are the deformation points for constructing the first plane.

3. The method of claim 2, wherein, The plate mold is a cuboid with uniform thickness, and has a flat upper top surface and a bottom surface.

4. The method of claim 1 wherein, The selection of the first coordinate axis and the second coordinate axis comprises the following steps: Selecting a plane parallel to any coordinate plane on the other side of the relatively deformed processing plane; Rotating the workpiece in the coordinate plane so that the reference plane is parallel to at least one coordinate axis of the coordinate plane; the coordinate axis parallel to the reference plane is the first coordinate axis, and the other coordinate axis in the coordinate plane is the second coordinate axis.

5. The method of claim 1 wherein, The method for obtaining the distance of the mark point from the reference plane of the part before deformation comprises: Based on the three-dimensional coordinate system of the numerical control machine tool, the coordinates of the mark point are obtained by using the spindle of the machine tool and the dial gauge; Based on the coordinates of the mark point, the deformation amount of the mark point relative to the reference plane is obtained.

6. The method of claim 5, wherein, The method for obtaining the coordinates of the mark point by using the spindle of the machine tool and the dial gauge comprises: Connecting the fixed end of the dial gauge to the spindle of the machine tool, contacting the measurement end of the dial gauge with the first mark point and setting the dial gauge to zero, and obtaining the coordinates of the first mark point from the coordinate display window of the numerical control machine tool; Adjusting the spindle of the machine tool to contact the measurement end of the dial gauge with the second mark point, and continuing to adjust the spindle of the machine tool until the dial gauge reads zero; obtaining the coordinates of the second mark point from the coordinate display window of the numerical control machine tool; According to the method for obtaining the coordinates of the second mark point, the coordinates of the third mark point and the fourth mark point are obtained in sequence.

7. The method of claim 6, wherein, Taking the y-axis as a coordinate axis, the x-axis as a second coordinate axis, and the z-axis as a third coordinate axis, the rotation angle C of the spindle of the machine tool around the third coordinate axis and the rotation angle B of the spindle of the machine tool around the first coordinate axis satisfy: ； γ is the rotation angle of the reference plane around the z-axis; x is the x-axis coordinate of the reference plane, y is the y-axis coordinate of the reference plane, and z is the z-axis coordinate of the reference plane; α is the rotation angle of the reference plane around the first coordinate axis, and β is the rotation angle of the reference plane around the second coordinate axis.

8. The method of claim 1 wherein, The rotation angle of the spindle of the machine tool around the coordinate axis is obtained from the vector coordinates of the rotation angle α of the reference plane around the first coordinate axis and the rotation angle β of the reference plane around the second coordinate axis, comprising: Based on the rotation angle α of the reference plane around the first coordinate axis and the rotation angle β of the reference plane around the second coordinate axis, the vector coordinates of the rotation angle of the first plane relative to the reference plane are obtained; Based on the rotation sequence of the spindle of the machine tool around different coordinate axes, the expression of the rotation angle of the spindle of the machine tool around the coordinate axis and the rotation vector coordinates of the spindle of the machine tool around the coordinate axis are obtained; Based on the fact that the rotation angle of the first plane relative to the reference plane is the same as the vector coordinates of the rotation angle of the spindle of the machine tool, the expression of the rotation angle of the spindle of the machine tool around the coordinate axis and the rotation angle of the first plane relative to the reference plane is obtained, and the rotation angle of the spindle of the machine tool around the coordinate axis is obtained from the rotation angle of the first plane relative to the reference plane.

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