High-precision machining method for the side surface of the straight-edge sector magnet of a cyclotron

Abstract

The present invention relates to the field of electromagnetic measurement technology, and particularly to a high-precision machining method for the side surface of a straight-edge sector magnet of a cyclotron, including: obtaining the adjusted cutting depth parameters for each magnet according to the machining height difference, cutting abnormality degree, average roughness, and initial cutting depth; screening all magnets according to the local roughness of each point cloud data on the surface of each magnet to obtain the magnets to be adjusted and the non-adjusted magnets; obtaining the corrected cutting parameters for the upper magnet of the cyclotron according to the differences in the adjusted cutting speed parameters, adjusted cutting feed amount parameters, and adjusted cutting depth parameters between the magnets to be adjusted and the non-adjusted magnets; and performing high-precision machining on the side surface of the straight-edge sector magnet of the cyclotron based on the corrected cutting parameters of the magnet. The present invention improves the consistency between the magnets and the precision of the side surface machining method of the magnet.

Description

Technical Field

[0001] The present invention relates to the technical field of electromagnetic measurement, and particularly to a high-precision machining method for the side surface of a straight-edge sector magnetic pole of a cyclotron. Background Art

[0002] A cyclotron is a device that uses a magnetic field to make charged particles move in a circular motion and repeatedly accelerates them through a high-frequency electric field during the motion. Since the performance of a cyclotron depends to a large extent on the uniformity and isochronism of the magnetic field; the high-precision machining of the side surface of a straight-edge sector magnetic pole is an important factor in ensuring the precise distribution of the magnetic field. And the accuracy of the magnetic field directly affects the quality and stability of the particle beam. The high-precision machined magnetic pole can reduce the error of the magnetic field, thereby improving the focusing degree of the particle beam and the uniformity of the energy distribution;

[0003] When designing a cyclotron, the weight of the accelerator is strictly limited, and it is a compact structure with a completely symmetric four-vane straight-edge sector structure; the four-vane straight-edge sector magnetic poles are circumferentially evenly distributed about the center line of the part, requiring absolute symmetry, uniformity, and consistency; however, at present, the machining of the magnetic poles often adopts a split structure, and each magnetic pole block is individually machined according to the same machining method and then assembled together; and the individual machining of each magnetic pole has high precision requirements, which will lead to the defect of weakened consistency between the magnetic poles. Summary of the Invention

[0004] In order to solve the above problems, the present invention provides a high-precision machining method for the side surface of a straight-edge sector magnetic pole of a cyclotron, and the method includes:

[0005] According to the point cloud data of each magnetic pole surface, obtain the average roughness of each magnetic pole and the local roughness of each point cloud data on each magnetic pole surface; screen the point cloud data on each magnetic pole surface through the local roughness to obtain the abnormal machining area of each magnetic pole; according to the proportion of the abnormal machining area, obtain the cutting abnormal degree of each magnetic pole;

[0006] Obtain the adjusted cutting speed parameter for each magnetic pole according to the cutting anomaly degree and the initial cutting speed; obtain the adjusted cutting feed parameter for each magnetic pole according to the adjusted cutting speed parameter and the initial cutting feed; obtain the machining height difference for each magnetic pole according to the distribution of the point cloud data on the surfaces of all magnetic poles; obtain the adjusted cutting depth parameter for each magnetic pole according to the machining height difference, the cutting anomaly degree, the average roughness, and the initial cutting depth; screen all magnetic poles according to the local roughness of each point cloud data on the surface of each magnetic pole to obtain the magnetic poles to be adjusted and the non-adjusted magnetic poles; obtain the corrected cutting parameters of the upper magnetic pole of the cyclotron according to the differences in the adjusted cutting speed parameters, the adjusted cutting feed parameters, and the adjusted cutting depth parameters between the magnetic poles to be adjusted and the non-adjusted magnetic poles, and perform high-precision machining on the side surface of the straight-edge sector magnetic pole of the cyclotron.

[0007] Preferably, the specific method for obtaining the average roughness of each magnetic pole and the local roughness of each point cloud data on the surface of each magnetic pole according to the point cloud data on the surface of each magnetic pole includes:

[0008] For any one magnetic pole on the cyclotron, input the point cloud data on the surface of the any one magnetic pole into a roughness measuring instrument to obtain the roughness of all point cloud data on the surface of the any one magnetic pole;

[0009] Take the mean value of the roughness of all point cloud data on the surface of the any one magnetic pole as the average roughness of the any one magnetic pole;

[0010] For any one point cloud data on the surface of the any one magnetic pole, preset a neighborhood parameter , take the any one point cloud data as the center of a spherical window, obtain a spherical window with a radius of , and denote the spherical window as the local neighborhood range of the any one point cloud data; take the mean value of the roughness of all point cloud data within the local neighborhood range of the any one point cloud data as the local roughness of the any one point cloud data.

[0011] Preferably, the specific method for screening the point cloud data on the surface of each magnetic pole through the local roughness to obtain the abnormal machining area of each magnetic pole includes:

[0012] Preset a target roughness parameter , for any one point cloud data on the surface of any one magnetic pole on the cyclotron, if the local roughness of the any one point cloud data is greater than or equal to the target roughness parameter , denote any one of the point cloud data as abnormal point cloud data; use the Convex Hull algorithm to limit all the abnormal point cloud data on any one of the magnetic pole surfaces, forming multiple closed regions, and all are denoted as abnormal machining regions.

[0013] Preferably, the method for obtaining the cutting abnormality degree of each magnetic pole according to the proportion of the abnormal machining regions specifically includes:

[0014] For any one of the abnormal machining regions of any one of the magnetic poles on the cyclotron, the ratio between the number of all point cloud data in the any one of the abnormal machining regions and the number of all point cloud data on the any one of the magnetic pole surfaces is denoted as the area occupancy ratio of the any one of the abnormal machining regions; the normalized value of the product of the cumulative sum of the area occupancy ratios of all the abnormal machining regions of the any one of the magnetic poles and the number of all the abnormal machining regions of the any one of the magnetic poles is used as the cutting abnormality degree of the any one of the magnetic poles.

[0015] Preferably, the method for obtaining the adjusted cutting speed parameter of each magnetic pole according to the cutting abnormality degree and the initial cutting speed specifically includes:

[0016] For any one of the magnetic poles on the cyclotron, the product of the cutting abnormality degree of the any one of the magnetic poles, the reciprocal of the current cutting machining times, and the initial cutting speed is denoted as the cutting speed adjustment factor of the any one of the magnetic poles; the sum of the initial cutting speed of the any one of the magnetic poles and the cutting speed adjustment factor is used as the adjusted cutting speed parameter of the any one of the magnetic poles.

[0017] Preferably, the method for obtaining the adjusted cutting feed amount parameter of each magnetic pole according to the adjusted cutting speed parameter and the initial cutting feed amount specifically includes:

[0018] For any one of the magnetic poles on the cyclotron, the normalized value of the difference between the adjusted cutting speed parameter and the initial cutting speed of the any one of the magnetic poles is denoted as the cutting speed difference value; the product of the cutting speed difference value and the initial cutting feed amount of the any one of the magnetic poles is denoted as the cutting feed amount adjustment factor; the difference between the initial cutting feed amount and the initial cutting feed amount of the any one of the magnetic poles is used as the adjusted cutting feed amount parameter of the any one of the magnetic poles.

[0019] Preferably, the method for obtaining the machining height difference of each magnetic pole according to the distribution of the point cloud data on all the magnetic pole surfaces specifically includes:

[0020] Perform horizontal plane fitting on all point cloud data on the surfaces of all magnetic poles to obtain the overall machining base plane of the magnetic poles; for any one magnetic pole on the cyclotron, perform horizontal plane fitting on all point cloud data on the surface of the any one magnetic pole to obtain the machining base plane of the any one magnetic pole; take the distance between the overall machining base plane of the magnetic poles and the machining base plane of the any one magnetic pole as the machining height difference of the any one magnetic pole.

[0021] Preferably, the method for obtaining the adjusted cutting depth parameter for each magnetic pole according to the machining height difference, cutting anomaly degree, average roughness, and initial cutting depth specifically includes:

[0022] For any one magnetic pole on the cyclotron, take the difference between the average roughness of the any one magnetic pole and the target roughness parameter and denote it as the first difference; take the product of the first difference and the cutting anomaly degree of the any one magnetic pole and denote it as the first product; take the ratio of the first product to the machining height difference of the any one magnetic pole and denote it as the cutting depth adjustment coefficient;

[0023] Take the product of the initial cutting depth and the cutting depth adjustment coefficient and denote it as the cutting depth adjustment value; take the difference between the initial cutting depth and the cutting depth adjustment value as the adjusted cutting depth parameter for the any one magnetic pole.

[0024] Preferably, the method for screening all magnetic poles according to the local roughness of each point cloud data on the surface of each magnetic pole to obtain the magnetic poles to be adjusted and the non-adjusted magnetic poles specifically includes:

[0025] For any one magnetic pole on the cyclotron, denote the standard deviation of the local roughness of all point cloud data on the surface of the any one magnetic pole as the roughness consistency of the any one magnetic pole;

[0026] Preset a fluctuation parameter , if the roughness consistency of the any one magnetic pole is less than or equal to the fluctuation parameter , denote the any one magnetic pole as a non-adjusted magnetic pole; if the roughness consistency of the any one magnetic pole is greater than the fluctuation parameter , denote the any one magnetic pole as a magnetic pole to be adjusted.

[0027] Preferably, the method for obtaining the corrected cutting parameters of the magnetic poles on the cyclotron according to the differences in the adjusted cutting speed parameters, adjusted feed rate parameters, and adjusted cutting depth parameters between the magnetic poles to be adjusted and the non-adjusted magnetic poles specifically includes:

[0028] For any non-adjustable magnetic pole, the absolute value of the difference between the average roughness of the any non-adjustable magnetic pole and the target roughness is denoted as the target difference of the any non-adjustable magnetic pole; among all non-adjustable magnetic poles, the non-adjustable magnetic pole with the smallest target difference is denoted as the target magnetic pole.

[0029] The normalized value of the absolute value of the difference between the mean value of the average roughness of all poles to be adjusted and the average roughness of the target magnetic pole is denoted as the roughness influence factor.

[0030] The absolute value of the difference between the mean value of the adjusted cutting speed parameters of all poles to be adjusted and the adjusted cutting speed parameters of the target magnetic pole is denoted as the cutting speed influence factor; the product of the cutting speed influence factor and the roughness influence factor is denoted as the cutting speed correction factor; the difference between the adjusted cutting speed parameters of the target magnetic pole and the cutting speed correction factor is denoted as the corrected cutting speed parameter; similarly, the corrected cutting feed parameter and the corrected cutting depth parameter are obtained.

[0031] The corrected cutting speed parameter, the corrected cutting feed parameter, and the corrected cutting depth parameter are used as the corrected cutting parameters of the upper magnetic pole of the cyclotron.

[0032] The beneficial effects of the technical solution of the present invention are as follows: The present invention obtains the adjusted cutting depth parameter of each magnetic pole according to the processing height difference, the cutting abnormality degree, the average roughness, and the initial cutting depth; screens all magnetic poles according to the local roughness of each point cloud data on the surface of each magnetic pole to obtain the poles to be adjusted and the non-adjustable magnetic poles; obtains the corrected cutting parameters of the upper magnetic pole of the cyclotron according to the differences in the adjusted cutting speed parameters, the adjusted cutting feed parameters, and the adjusted cutting depth parameters between the poles to be adjusted and the non-adjustable magnetic poles; performs high-precision machining on the side surface of the straight-edge sector magnetic pole of the cyclotron based on the corrected cutting parameters of the magnetic pole; improves the consistency between the magnetic poles and the accuracy of the magnetic pole side machining method through the adaptability of the cutting parameters during the magnetic pole machining process. Description of the Drawings

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0034] Figure 1 It is a flowchart of the steps of the high-precision machining method for the side surface of the straight-edge sector magnetic pole of the cyclotron of the present invention. Detailed Embodiments

[0035] In order to further elaborate on the technical means and effects adopted by the present invention to achieve the intended invention purpose, the following, in conjunction with the accompanying drawings and preferred embodiments, details the specific implementation manner, structure, features and effects of the high-precision machining method for the side surface of the straight-edge sector magnet of a cyclotron according to the present invention. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. In addition, the specific features, structures or characteristics in one or more embodiments can be combined in any suitable form.

[0036] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs.

[0037] The following specifically describes the specific solution of the high-precision machining method for the side surface of the straight-edge sector magnet of a cyclotron provided by the present invention in conjunction with the accompanying drawings.

[0038] Please refer to Figure 1 , which shows a flowchart of the steps of the high-precision machining method for the side surface of the straight-edge sector magnet of a cyclotron provided by an embodiment of the present invention. The method includes the following steps:

[0039] Step S001: Obtain the point cloud data of all the magnet surfaces on the cyclotron, and the initial cutting parameters corresponding to each magnet; the initial cutting parameters include the initial cutting speed, the initial cutting depth, and the initial cutting feed rate.

[0040] Specifically, first, it is necessary to collect the point cloud data of all the magnet surfaces on the cyclotron, and the initial cutting parameters corresponding to each magnet. The specific process is as follows:

[0041] Use a laser scanner to perform point cloud acquisition on the surfaces of all the magnets on the cyclotron to obtain all the point cloud data of each magnet surface on the cyclotron;

[0042] For any one magnet, preset the initial cutting speed to 300 mm / min, the initial cutting depth to 1 mm, and the initial cutting feed rate to 0.2 mm / r; regard the initial cutting speed, the initial cutting depth, and the initial cutting feed rate as the initial cutting parameters corresponding to any one magnet.

[0043] So far, the point cloud data of all the magnet surfaces on the cyclotron and the initial cutting parameters corresponding to each magnet are obtained through the above method.

[0044] Step S002: According to the point cloud data of each pole surface, obtain the average roughness of each pole and the local roughness of each point cloud data on each pole surface; screen the point cloud data on each pole surface through the local roughness to obtain the abnormal machining area of each pole; according to the proportion of the abnormal machining area, obtain the cutting abnormality degree of each pole.

[0045] It should be noted that the cutting parameters are important factors affecting the machining accuracy of the poles. As the cutting level increases, the difference between the machined poles and the theoretical machining drawings becomes smaller and smaller, the allowable error decreases, and the requirement for accuracy gradually increases; therefore, the cutting parameters are not constant during the layer cutting process.

[0046] Preferably, in some implementation manners of the embodiments of the present invention, the specific method for obtaining the average roughness of each pole and the local roughness of each point cloud data on each pole surface according to the point cloud data of each pole surface is as follows:

[0047] Preset a neighborhood parameter , where in this embodiment, is taken as an example for description, and this embodiment does not make specific limitations, where is determined according to the specific implementation situation;

[0048] For any one pole on the cyclotron, input the point cloud data of the surface of the any one pole into a roughness measuring instrument to obtain the roughness of all the point cloud data on the surface of the any one pole;

[0049] Take the mean value of the roughness of all the point cloud data on the surface of the any one pole as the average roughness of the any one pole;

[0050] For any one point cloud data on the pole surface, take this point cloud data as the center of a spherical window, obtain a spherical window with a radius of , and record this spherical window as the local neighborhood range of this point cloud data; take the mean value of the roughness of all the point cloud data within the local neighborhood range of this point cloud data as the local roughness of this point cloud data.

[0051] Among them, the spherical window is a three-dimensional spherical window.

[0052] Preferably, in some implementation manners of the embodiments of the present invention, the specific method for screening the point cloud data on each pole surface through the local roughness to obtain the abnormal machining area of each pole is as follows:

[0053] Preset a target roughness parameter , where in this embodiment, is taken as an example for description, and this embodiment does not make specific limitations, where It depends on the specific implementation situation;

[0054] For any point cloud data on any point on the surface of any magnetic pole of the cyclotron, if the local roughness of the point cloud data is greater than or equal to the target roughness parameter , mark the point cloud data as abnormal point cloud data; use the Convex Hull algorithm to limit all the abnormal point cloud data on the surface of any magnetic pole to form multiple closed regions, and all are marked as abnormal machining regions.

[0055] It should be noted that if the average roughness of the current magnetic pole is less than the target roughness threshold, it means that the smoothness of the current magnetic pole surface meets the machining requirements of the cyclotron magnetic pole, and then the parameters are not adjusted at this time; if the average roughness of the current magnetic pole is greater than or equal to the target roughness, it means that some regions inside the magnetic pole do not meet the machining requirements and there are obvious rough features, which means that the cutting parameters are inappropriate; The Convex Hull algorithm is a prior art and will not be elaborated here in this embodiment.

[0056] Preferably, in some implementation manners of the embodiment of the present invention, the specific method for obtaining the cutting abnormality degree of each magnetic pole according to the proportion of the abnormal machining region is:

[0057] For any abnormal machining region of any magnetic pole of the cyclotron, the ratio between the number of all point cloud data in the abnormal machining region and the number of all point cloud data on the surface of any magnetic pole is recorded as the area occupancy ratio of the abnormal machining region; the normalized value of the product of the cumulative sum of the area occupancy ratios of all abnormal machining regions of any magnetic pole and the number of all abnormal machining regions of any magnetic pole is used as the cutting abnormality degree of any magnetic pole;

[0058] The specific formula is:

[0059]

[0060] In the formula, represents the cutting abnormality degree of the magnetic pole; represents the number of all abnormal machining regions of the magnetic pole; represents the th abnormal machining region of the magnetic pole and the number of all point cloud data in it; represents the number of all point cloud data on the surface of the magnetic pole; represents the linear normalization function.

[0061] It should be noted that the more abnormal machining areas there are and the larger the area of the abnormal machining areas, the more significant the magnetic pole abnormality in the machining indicates. This shows that the machining cutting parameters of the current magnetic pole need to be adjusted to ensure the machining accuracy of the magnetic pole. If the abnormality is more significant, it means that the cutting parameters of the current magnetic pole are seriously abnormal and do not meet the machining requirements for the side of the sector magnetic pole. Then, a higher adjustment amplitude of the parameter machining parameters is required.

[0062] Thus far, the cutting abnormality degree of each magnetic pole is obtained by the above method.

[0063] Step S003: Obtain the adjusted cutting speed parameter of each magnetic pole according to the cutting abnormality degree and the initial cutting speed; obtain the adjusted cutting feed parameter of each magnetic pole according to the adjusted cutting speed parameter and the initial cutting feed; obtain the machining height difference of each magnetic pole according to the distribution of the point cloud data on the surfaces of all magnetic poles; obtain the adjusted cutting depth parameter of each magnetic pole according to the machining height difference, the cutting abnormality degree, the average roughness, and the initial cutting depth; screen all magnetic poles according to the local roughness of each point cloud data on the surface of each magnetic pole to obtain the magnetic poles to be adjusted and the non-adjusted magnetic poles; obtain the corrected cutting parameters of the upper magnetic pole of the cyclotron according to the differences in the adjusted cutting speed parameter, the adjusted cutting feed parameter, and the adjusted cutting depth parameter between the magnetic poles to be adjusted and the non-adjusted magnetic poles.

[0064] It should be noted that the greater the cutting abnormality degree, the greater the difference between the cutting roughness and the theoretical roughness of the magnetic pole, and the greater the adjustment amplitude of the cutting parameters is required to ensure the machining accuracy. However, the adjustment of the cutting parameters cannot be infinitely enlarged and is affected by the number of cutting times. In this case, it is considered that the cutting speed is too small, resulting in repeated cutting of these positions during the cutting process, and obvious cutting marks appear. It is necessary to increase the cutting speed to improve the cutting roughness of the magnetic pole side. However, as the number of machining times increases, the requirement for accuracy also gradually increases, and it is necessary to increase the cutting speed to prevent obvious machining textures from being left on the magnetic pole side due to too small cutting speed. Therefore, there are certain requirements for the range of the cutting speed in different cutting processes. In rough machining or when there is a high machining tolerance, a larger fluctuation range of the cutting speed can be given for the sake of faster machining efficiency. As the machining accuracy increases, the fluctuation of the cutting speed decreases to prevent obvious textures from appearing.

[0065] Preferably, in some implementation manners of the embodiment of the present invention, the specific method for obtaining the adjusted cutting speed parameter of each magnetic pole according to the cutting abnormality degree and the initial cutting speed is as follows:

[0066] For any one magnetic pole on the cyclotron, the product of the abnormal cutting degree of the any one magnetic pole, the reciprocal of the current cutting times, and the initial cutting speed is denoted as the cutting speed adjustment factor of the any one magnetic pole; the sum of the initial cutting speed of the any one magnetic pole and the cutting speed adjustment factor is used as the adjusted cutting speed parameter of the any one magnetic pole;

[0067] The specific formula is:

[0068]

[0069] In the formula, represents the adjusted cutting speed parameter of the magnetic pole; represents the initial cutting speed; represents the abnormal cutting degree of the magnetic pole; represents the current cutting times of the magnetic pole.

[0070] It should be noted that increasing the cutting speed can effectively improve the machining accuracy of the magnetic pole side, but the increase in speed will cause the cutting force to change. An excessive cutting speed will cause the cutting force to decrease significantly, resulting in risks of impact and wear between the cutting tool and the machined magnetic pole. Therefore, there is a significant correlation between the cutting speed and the cutting feed rate, and single adjustment cannot be performed; that is, after increasing the cutting speed, finer cutting traces are retained at the same time to prevent more obvious impact and wear risks caused by excessive feed rate; thus, the adjusted cutting feed rate is adjusted according to the change in the cutting speed.

[0071] Preferably, in some implementation manners of the embodiments of the present invention, the specific method for obtaining the adjusted cutting feed rate parameter of each magnetic pole according to the adjusted cutting speed parameter and the initial cutting feed rate is:

[0072] For any one magnetic pole on the cyclotron, the normalized value of the difference between the adjusted cutting speed parameter and the initial cutting speed of the any one magnetic pole is denoted as the cutting speed difference value; the product of the cutting speed difference value and the initial cutting feed rate of the any one magnetic pole is denoted as the cutting feed rate adjustment factor; the difference between the initial cutting feed rate of the any one magnetic pole and the initial cutting feed rate is used as the adjusted cutting feed rate parameter of the any one magnetic pole;

[0073] The specific formula is:

[0074]

[0075] In the formula, represents the adjusted cutting feed rate parameter of the magnetic pole; represents the initial cutting feed rate; Represents the adjusted cutting speed parameter of the magnetic pole; Represents the initial cutting speed; Represents the linear normalization function.

[0076] It should be noted that the above-mentioned adjusted cutting parameters are obtained according to the roughness of the side surface of the magnetic pole, but there are the following problems: as the number of layer cutting on the side surface of the magnetic pole increases, the remaining amount on the side surface of the magnetic pole becomes smaller and smaller. If the surface roughness of the magnetic pole material is abnormal, it is still necessary to evaluate according to the roughness, but the layer cutting tolerance at this time becomes smaller; and the above only analyzes the cutting effect of each individual magnetic pole side surface. Since there may still be a large roughness difference between multiple magnetic poles, it does not have symmetry, uniformity, and consistency; and the cutting depth of the side surface of the magnetic pole during the layer cutting process is an important factor affecting the consistency of the magnetic pole and ensuring the machining accuracy of the side surface of the magnetic pole. Therefore, it is necessary to adjust the cutting depth during this process; and the cutting parameters: cutting speed and cutting feed rate should also be corrected to a certain extent as the number of layer cutting increases.

[0077] Preferably, in some implementation manners of the embodiments of the present invention, the specific method for obtaining the machining height difference of each magnetic pole according to the distribution of the point cloud data on the surfaces of all magnetic poles is:

[0078] Perform a horizontal plane fitting on all the point cloud data on the surfaces of all magnetic poles to obtain the overall machining base plane of the magnetic poles; for any one magnetic pole on the cyclotron, perform a horizontal plane fitting on all the point cloud data on the surface of the any one magnetic pole to obtain the machining base plane of the any one magnetic pole; take the distance between the overall machining base plane of the magnetic poles and the machining base plane of the any one magnetic pole as the machining height difference of the any one magnetic pole;

[0079] Preferably, in some implementation manners of the embodiments of the present invention, the specific method for obtaining the adjusted cutting depth parameter of each magnetic pole according to the machining height difference, cutting abnormality degree, average roughness, and initial cutting depth is:

[0080] For any one magnetic pole on the cyclotron, take the difference between the average roughness of the any one magnetic pole and the target roughness parameter and denote it as the first difference; denote the product of the first difference and the cutting abnormality degree of the any one magnetic pole as the first product; denote the ratio of the first product to the machining height difference of the any one magnetic pole as the cutting depth adjustment coefficient;

[0081] Denote the product of the initial cutting depth and the cutting depth adjustment coefficient as the cutting depth adjustment value; take the difference between the initial cutting depth and the cutting depth adjustment value as the adjusted cutting depth parameter of the any one magnetic pole;

[0082] The specific formula is:

[0083]

[0084] In the formula, represents the adjusted cutting depth parameter of the magnetic pole; represents the initial cutting depth; represents the cutting abnormality degree of the magnetic pole; represents the average roughness of the magnetic pole; represents the target roughness parameter; represents the machining height difference of the magnetic pole; represents the linear normalization function.

[0085] It should be noted that the machining height difference reflects the remaining amount of the current machining of the magnetic pole, and the remaining amount reflects the machining tolerance condition of the side surface of the magnetic pole. The larger the machining height difference, the higher the tolerance, and the larger the adjusted cutting depth parameter; as the machining height difference decreases during the layer cutting process, the machining accuracy of the magnetic pole should be higher and higher; when the roughness does not meet the standard, the greater the difference between the average roughness of the magnetic pole and the theoretical roughness, the greater the corresponding cutting abnormality degree, which indicates that the machining accuracy of the side surface of the magnetic pole is smaller, and more adjustments of the cutting process are required, and more tolerance space is needed for cutting trial and error, and the corresponding cutting depth should be reduced; if there is abnormal cutting of the magnetic pole currently, that is, the greater the cutting abnormality degree, the more machining tolerance space of the magnetic pole is required, and a smaller cutting depth is needed.

[0086] It should be noted that while the magnetic pole has high machining accuracy, it is also necessary to ensure the consistency, symmetry, and uniformity of the magnetic pole; therefore, the roughness of each magnetic pole also needs to have consistency and the same height; the same height can be achieved by using the same cutting depth for all magnetic poles during the cutting process; therefore, considering the influence of roughness, the cutting parameters are corrected.

[0087] Preferably, in some implementation manners of the embodiment of the present invention, the specific method for screening all magnetic poles according to the local roughness of each point cloud data on the surface of each magnetic pole to obtain the magnetic poles to be adjusted and the non-adjusted magnetic poles is as follows:

[0088] For any magnetic pole on the cyclotron, the standard deviation of the local roughness of all point cloud data on the surface of the any magnetic pole is denoted as the roughness consistency of the any magnetic pole;

[0089] Preset a fluctuation parameter , where in this embodiment, is taken as an example for description, and this embodiment is not specifically limited, where is determined according to the specific implementation situation;

[0090] If the roughness consistency of the any magnetic pole is less than or equal to the fluctuation parameter Denote any one of the magnetic poles as a non-adjusted magnetic pole; if the roughness consistency of any one of the magnetic poles is greater than the fluctuation parameter Denote any one of the magnetic poles as a magnetic pole to be adjusted.

[0091] Preferably, in some implementation manners of the embodiments of the present invention, according to the differences in the adjusted cutting speed parameter, the adjusted cutting feed parameter, and the adjusted cutting depth parameter between the magnetic poles to be adjusted and the non-adjusted magnetic poles, the specific method for obtaining the adjusted cutting parameters of the upper magnetic poles of the cyclotron is as follows:

[0092] For any one non-adjusted magnetic pole, denote the absolute value of the difference between the average roughness of any one non-adjusted magnetic pole and the target roughness as the target difference of any one non-adjusted magnetic pole; among all non-adjusted magnetic poles, denote the non-adjusted magnetic pole with the smallest target difference as the target magnetic pole;

[0093] Denote the normalized value of the absolute value of the difference between the average value of the average roughness of all magnetic poles to be adjusted and the average roughness of the target magnetic pole as the roughness influence factor;

[0094] Denote the absolute value of the difference between the average value of the adjusted cutting speed parameters of all magnetic poles to be adjusted and the adjusted cutting speed parameter of the target magnetic pole as the cutting speed influence factor; denote the product of the cutting speed influence factor and the roughness influence factor as the cutting speed correction factor; denote the difference between the adjusted cutting speed parameter of the target magnetic pole and the cutting speed correction factor as the corrected cutting speed parameter;

[0095] Denote the absolute value of the difference between the average value of the adjusted cutting feed parameters of all magnetic poles to be adjusted and the adjusted cutting feed parameter of the target magnetic pole as the cutting feed influence factor; denote the product of the cutting feed influence factor and the roughness influence factor as the cutting feed correction factor; denote the difference between the adjusted cutting feed parameter of the target magnetic pole and the cutting feed correction factor as the corrected cutting feed parameter;

[0096] Denote the absolute value of the difference between the average value of the adjusted cutting depth parameters of all magnetic poles to be adjusted and the adjusted cutting depth parameter of the target magnetic pole as the cutting depth influence factor; denote the product of the cutting depth influence factor and the roughness influence factor as the cutting depth correction factor; denote the difference between the adjusted cutting depth parameter of the target magnetic pole and the cutting depth correction factor as the corrected cutting depth parameter;

[0097] Take the corrected cutting speed parameter, the corrected cutting feed parameter, and the corrected cutting depth parameter as the corrected cutting parameters of the upper magnetic poles of the cyclotron.

[0098] So far, the corrected cutting parameters of the upper magnetic pole of the cyclotron are obtained through the above method.

[0099] Step S004: Perform high-precision machining on the side surface of the straight-edge sector magnetic pole of the cyclotron based on the corrected cutting parameters of the magnetic pole.

[0100] Preferably, in some implementation manners of the embodiment of the present invention, the specific method for performing high-precision machining on the side surface of the straight-edge sector magnetic pole of the cyclotron based on the corrected cutting parameters of the magnetic pole is as follows:

[0101] Preset a height parameter , where in this embodiment, is taken as an example for description, and this embodiment does not make specific limitations, where is determined according to the specific implementation situation;

[0102] According to the corrected cutting parameters of the upper magnetic pole of the cyclotron, adjust the cutting parameters of the cyclotron, and perform cutting on the upper magnetic pole of the cyclotron until the average value of the machining height differences of all magnetic poles on the cyclotron is less than the height parameter .

[0103] As an embodiment, the specific steps for cutting the upper magnetic pole of the cyclotron using the corrected cutting parameters include:

[0104] 1. Leave a 3-mm allowance on each surface after semi-finishing the magnetic pole.

[0105] 2. Select a high-precision large-scale CNC gantry boring and milling machine and a vibration-proof cutting tool bar.

[0106] 3. Perform trial milling machining with a cutting amount of 0.5 mm and a cutting depth of 1 mm. When programming the CNC machining program used by the machine tool during trial cutting, adopt a programming strategy with layer cutting priority to ensure that the same height has consistent and symmetric features first.

[0107] 4. Check the machining accuracy of the side surface of the magnetic pole with a laser tracker.

[0108] 5. Finish boring the center hole to meet the drawing requirements.

[0109] 6. Use the center finish-bored hole as a reference to measure the relative values of each side surface, compare with the results detected by the laser tracker, and record each relative value.

[0110] 7. Finish milling the side surface, with the finish machining cutting amount according to the corrected feed rate parameter, the cutting speed according to the corrected cutting speed parameter, and the cutting depth of 1 mm for the corrected cutting depth parameter.

[0111] 8. Finish correcting the side surface, correct the side surface machining according to the relative value measured to the center finish-bored hole, and control the relative value error of each surface within 0.02 mm.

[0112] 9. Finish milling the assembly surface of the gib, using a solid carbide milling cutter. Milling multiple times, the relative error of each surface is controlled within 0.02 mm.

[0113] So far, this embodiment is completed.

[0114] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A high-precision machining method for the side of a cyclotron straight-edge sector-shaped magnetic pole, characterized in that: The method comprises the following steps: According to the point cloud data on the surface of each magnetic pole, the average roughness of each magnetic pole and the local roughness of each point cloud data on the surface of each magnetic pole are obtained; the point cloud data on the surface of each magnetic pole are screened by the local roughness to obtain the abnormal processing area of ​​each magnetic pole; according to the proportion of the abnormal processing area, the degree of cutting abnormality of each magnetic pole is obtained; According to the degree of cutting abnormality and the initial cutting speed, the adjusted cutting speed parameters of each magnetic pole are obtained; according to the adjusted cutting speed parameters and the initial cutting feed, the adjusted cutting feed parameters of each magnetic pole are obtained; according to the distribution of point cloud data on the surfaces of all magnetic poles, the processing height difference of each magnetic pole is obtained; according to the processing height difference, the degree of cutting abnormality, the average roughness and the initial cutting depth, the adjusted cutting depth parameters of each magnetic pole are obtained; according to the local roughness of each point cloud data on the surface of each magnetic pole, all magnetic poles are screened to obtain the magnetic poles to be adjusted and the non-adjusted magnetic poles; according to the differences in the adjusted cutting speed parameters, the adjusted cutting feed parameters and the adjusted cutting depth parameters between the magnetic poles to be adjusted and the non-adjusted magnetic poles, the corrected cutting parameters of the magnetic poles on the cyclotron are obtained, and the side surfaces of the straight-edge sector-shaped magnetic poles of the cyclotron are processed with high precision.

2. The high-precision machining method for the side surface of a cyclotron straight-edge sector-shaped magnetic pole according to claim 1, characterized in that: The specific method of obtaining the average roughness of each magnetic pole and the local roughness of each point cloud data on the surface of each magnetic pole according to the point cloud data on the surface of each magnetic pole is as follows: For any magnetic pole on the cyclotron, inputting point cloud data of the surface of the any magnetic pole into a roughness measuring instrument to obtain the roughness of all point cloud data on the surface of the any magnetic pole; Taking the mean value of the roughness of all point cloud data on the surface of any one magnetic pole as the average roughness of any one magnetic pole; For any point cloud data on any magnetic pole surface, a neighborhood parameter is preset. , taking any point cloud data as the center of the spherical window, obtain the radius A spherical window is formed, and the spherical window is recorded as the local neighborhood range of any point cloud data; the average value of the roughness of all point cloud data within the local neighborhood range of any point cloud data is taken as the local roughness of any point cloud data.

3. The high-precision machining method for the side surface of a cyclotron straight-edge sector-shaped magnetic pole according to claim 1, characterized in that: The point cloud data on the surface of each magnetic pole is screened by local roughness to obtain the abnormal processing area of ​​each magnetic pole, including the specific method of: Preset a target roughness parameter For any point cloud data on the surface of any magnetic pole on the cyclotron, if the local roughness of any point cloud data is greater than or equal to the target roughness parameter , record any one of the point cloud data as abnormal point cloud data; use the Convex Hull algorithm to restrict all abnormal point cloud data on the surface of any one of the magnetic poles to form multiple closed areas, and all of them are recorded as abnormal processing areas.

4. The high-precision machining method for the side surface of a cyclotron straight-edge sector-shaped magnetic pole according to claim 1, characterized in that: The specific method for obtaining the degree of cutting abnormality of each magnetic pole according to the proportion of abnormal processing area is as follows: For any abnormal processing area of ​​any magnetic pole on the cyclotron, the ratio of the number of all point cloud data in the any abnormal processing area to the number of all point cloud data on the surface of any magnetic pole is recorded as the area ratio of the any abnormal processing area; the normalized value of the product of the cumulative sum of the area ratios of all abnormal processing areas of any magnetic pole and the number of all abnormal processing areas of any magnetic pole is taken as the cutting abnormality degree of any magnetic pole.

5. The high-precision machining method for the side surface of a cyclotron straight-edge sector-shaped magnetic pole according to claim 1, characterized in that: The method of obtaining the adjusted cutting speed parameter of each magnetic pole according to the cutting abnormality degree and the initial cutting speed includes: For any magnetic pole on the cyclotron, the product of the cutting abnormality degree of the any magnetic pole, the inverse of the current cutting processing times and the initial cutting speed is recorded as the cutting speed adjustment factor of the any magnetic pole; the sum of the initial cutting speed of the any magnetic pole and the cutting speed adjustment factor is taken as the adjusted cutting speed parameter of the any magnetic pole.

6. The high-precision machining method for the side surface of a cyclotron straight-edge sector-shaped magnetic pole according to claim 1, characterized in that: The method of obtaining the adjusted cutting feed parameter of each magnetic pole according to the adjusted cutting speed parameter and the initial cutting feed includes: For any magnetic pole on the cyclotron, the normalized value of the difference between the adjusted cutting speed parameter of any magnetic pole and the initial cutting speed is recorded as the cutting speed difference value; the product of the cutting speed difference value and the initial cutting feed of any magnetic pole is recorded as the cutting feed adjustment factor; the difference between the initial cutting feed of any magnetic pole and the initial cutting feed is used as the adjusted cutting feed parameter of any magnetic pole.

7. The high-precision machining method for the side surface of a cyclotron straight-edge sector-shaped magnetic pole according to claim 1, characterized in that: The specific method of obtaining the processing height difference of each magnetic pole according to the distribution of the point cloud data of all magnetic pole surfaces is as follows: All point cloud data on the surfaces of all magnetic poles are fitted in a horizontal plane to obtain the overall processing base plane of the magnetic poles; for any magnetic pole on the cyclotron, all point cloud data on the surface of any magnetic pole are fitted in a horizontal plane to obtain the processing base plane of the any magnetic pole; the distance between the overall processing base plane of the magnetic pole and the processing base plane of any magnetic pole is used as the processing height difference of the any magnetic pole.

8. The high-precision machining method for the side surface of a cyclotron straight-edge sector-shaped magnetic pole according to claim 3, characterized in that: The method of obtaining the adjusted cutting depth parameter of each magnetic pole according to the machining height difference, the degree of cutting abnormality, the average roughness and the initial cutting depth includes: For any magnetic pole on the cyclotron, the average roughness of any magnetic pole is compared with the target roughness parameter The difference is recorded as the first difference; The product of the first difference and the cutting abnormality degree of any one of the magnetic poles is recorded as the first product; the ratio of the first product to the machining height difference of any one of the magnetic poles is recorded as the cutting depth adjustment coefficient; The product of the initial cutting depth and the cutting depth adjustment coefficient is recorded as the cutting depth adjustment value; the difference between the initial cutting depth and the cutting depth adjustment value is used as the adjusted cutting depth parameter of any one magnetic pole.

9. The high-precision machining method for the side surface of a cyclotron straight-edge sector-shaped magnetic pole according to claim 1, characterized in that: The specific method of screening all magnetic poles according to the local roughness of each point cloud data on the surface of each magnetic pole to obtain the magnetic poles to be adjusted and the magnetic poles not to be adjusted includes: For any magnetic pole on the cyclotron, the standard deviation of the local roughness of all point cloud data on the surface of the any magnetic pole is recorded as the roughness consistency of the any magnetic pole; Preset a fluctuation parameter , if the roughness consistency of any of the magnetic poles is less than or equal to the fluctuation parameter , record any one of the magnetic poles as a non-adjusted magnetic pole; if the roughness consistency of any one of the magnetic poles is greater than the fluctuation parameter , any one of the magnetic poles is recorded as the magnetic pole to be adjusted.

10. The high-precision machining method for the side surface of a cyclotron straight-edge sector-shaped magnetic pole according to claim 1, characterized in that: The method of obtaining the corrected cutting parameters of the upper magnetic pole of the cyclotron according to the difference between the adjusted cutting speed parameter, the adjusted cutting feed parameter and the adjusted cutting depth parameter between the magnetic pole to be adjusted and the non-adjusted magnetic pole includes the following specific methods: For any non-adjustment magnetic pole, the absolute value of the difference between the average roughness of the any non-adjustment magnetic pole and the target roughness is recorded as the target difference of the any non-adjustment magnetic pole; among all non-adjustment magnetic poles, the non-adjustment magnetic pole with the smallest target difference is recorded as the target magnetic pole; The normalized value of the absolute value of the difference between the average roughness of all magnetic poles to be adjusted and the average roughness of the target magnetic pole is recorded as the roughness influence factor; The absolute value of the difference between the average of the adjusted cutting speed parameters of all the magnetic poles to be adjusted and the adjusted cutting speed parameter of the target magnetic pole is recorded as the cutting speed influence factor; the product of the cutting speed influence factor and the roughness influence factor is recorded as the cutting speed correction factor; The difference between the adjusted cutting speed parameter of the target magnetic pole and the cutting speed correction factor is recorded as the corrected cutting speed parameter; Similarly, the corrected cutting feed parameter and the corrected cutting depth parameter are obtained; The corrected cutting speed parameter, the corrected cutting feed parameter and the corrected cutting depth parameter are used as the corrected cutting parameters of the upper magnetic pole of the cyclotron.

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