Integral blade ring finishing joint mark control method and system based on on-machine measurement

Abstract

The present invention discloses a method for controlling tool marks during the finishing of an integral blade ring based on on-machine measurement. The method comprises: planning an on-machine measurement path for the machined side on the cross section of the blade to obtain theoretical coordinates of a first set of measurement points, and measuring the actual coordinates of the first set of measurement points; calculating the error between the theoretical and actual coordinates of the first set of measurement points to obtain the contour allowance of the machined side, and adjusting the tool path parameters of the unmachined side based on the error; flipping the blade ring over and clamping it; planning an on-machine measurement path for the machined side on the blade base and back of the blade to obtain theoretical coordinates of a second set of measurement points, and measuring the actual coordinates of the second set of measurement points; and calculating the angular error of the blade ring after flipping over based on the theoretical and actual coordinates of the second set of measurement points. The present invention can effectively control tool marks during the finishing of an integral blade ring, significantly reduce the number of trial cuts, and greatly improve machining efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of blade ring processing, and in particular to a method and system for controlling tool marks during the finishing of an integral blade ring based on on-machine measurement. Background Art

[0002] Due to the influence of the workpiece structure, the CNC milling finishing process of the integral blade ring of the aircraft engine usually requires turning over and feeding from both sides of the leading edge and the trailing edge respectively. Feeding from both sides of the turning over will introduce new problems to the processing of the integral blade ring. Among them, the control of the tool mark of the processing on both sides is particularly important. Considering the aerodynamic performance of the blade ring, the tool mark control of the turning over processing is very strict. Therefore, the control of the tool mark must be considered in the process arrangement and the planning of the processing path. The structure of the integral blade ring is as follows: Figure 1 As shown, it includes an outer shroud 1, an inner hub 2, and blades 3 arranged between the shroud 1 and the hub 2.

[0003] Currently, manual methods are used to adjust the angular position of the workpiece and the machining allowance on the opposite side to control the cutter mark during the finishing of the blade ring. This method requires a high level of operator experience, and it is difficult to find the appropriate parameters in a single adjustment. It is often necessary to gradually find the adjustment parameters that meet the cutter mark tolerance requirements through multiple trial cuts. The parameter selection for the first trial cut requires a high level of experience from the process technician and poses a significant quality risk. At the same time, multiple trial cuts are required to find the appropriate parameters, which also has a significant impact on the overall processing efficiency of the part. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a method for controlling the tool marks of the finishing of the integral blade ring based on on-machine measurement, which can effectively control the tool marks of the finishing of the integral blade ring, significantly reduce the number of trial cutting processes, and greatly improve the processing efficiency.

[0005] In order to solve the above problems, the present invention provides a method for controlling tool marks in finishing of an integral blade ring based on on-machine measurement, which comprises the following steps:

[0006] S1. Planning an on-machine measurement path of the machined side on the cross section of the blade to obtain theoretical coordinates of a first set of measurement points, and performing measurements to obtain actual coordinates of the first set of measurement points;

[0007] S2. Calculate the error between the theoretical coordinates and the actual coordinates of the first set of measurement points to obtain the contour allowance of the machined side, and adjust the tool path parameters of the unmachined side according to the contour allowance of the machined side;

[0008] S3. Turn the blade ring over and clamp it;

[0009] S4. Planning an on-machine measurement path for the machined side of the blade base and blade back to obtain theoretical coordinates of a second set of measurement points, and performing measurements to obtain actual coordinates of the second set of measurement points;

[0010] S5. Calculate the angular error of the blade ring after turning over based on the theoretical coordinates and actual coordinates of the second set of measurement points;

[0011] S6. Adjust the angular position of the blade ring after turning over and clamping according to the angular error;

[0012] S7. Process the unprocessed side according to the adjusted tool path parameters of the unprocessed side.

[0013] As a further improvement of the present invention, step S2 includes: calculating the error between the theoretical coordinates and the actual coordinates of the first group of measurement points to obtain a group of error values, obtaining the contour allowance of the processed side according to the average value of the group of error values, and adjusting the tool path parameters of the unprocessed side according to the contour allowance of the processed side; or, obtaining the contour allowance of the processed side according to the average value of the maximum and minimum values ​​in a group of error values, and adjusting the tool path parameters of the unprocessed side according to the contour allowance of the processed side.

[0014] As a further improvement of the present invention, step S3 includes: turning over the leaf ring for clamping, and positioning it according to the angular feature; wherein the angular feature is a feature on the leaf ring that can determine the angular position.

[0015] As a further improvement of the present invention, step S5 includes:

[0016] Assume there is a rotation transformation T A , so that the actual coordinates of the second set of measurement points undergo a rotation transformation T A After that, the sum of the squares of the distances between the theoretical coordinates of the second set of measurement points is minimized, then the rotation transformation T A is the optimal transformation of the blade ring from the actual angular position to the theoretical angular position; solve the rotation transformation T A , and get the angular error.

[0017] As a further improvement of the present invention, since the rotation transformation T representing the angular direction A is the rotation transformation around the Z axis, so the rotation transformation T A for:

[0018]

[0019] Where α is the angular error.

[0020] As a further improvement of the present invention, in step S1 , an on-machine measurement path of the machined side is planned on multiple cross sections of the blade, measurement points are planned on the multiple cross sections, and all measurement points are combined to obtain a first group of measurement points.

[0021] The present invention also provides a tool mark control system for finishing of an integral blade ring based on on-machine measurement, which comprises:

[0022] A first path planning and measurement module is used to plan an on-machine measurement path of the machined side on the cross section of the blade, obtain theoretical coordinates of a first set of measurement points, and perform measurements to obtain actual coordinates of the first set of measurement points;

[0023] an error calculation module, for calculating the error between the theoretical coordinates and the actual coordinates of the first set of measurement points to obtain the contour allowance of the machined side, and adjusting the tool path parameters of the unmachined side according to the contour allowance of the machined side;

[0024] The second path planning and measurement module is used to plan the on-machine measurement path of the machined side on the blade base and blade back after the blade ring is turned over and clamped, obtain the theoretical coordinates of the second set of measurement points, and measure and obtain the actual coordinates of the second set of measurement points;

[0025] An angular error calculation module, used to calculate the angular error after the blade ring is turned over based on the theoretical coordinates and actual coordinates of the second set of measurement points;

[0026] The processing module is used to adjust the angular position of the blade ring after flipping and clamping according to the angular error, and then process the unprocessed side according to the adjusted tool path parameters of the unprocessed side.

[0027] The present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of any one of the above methods when executing the program.

[0028] The present invention also provides a computer-readable storage medium having a computer program stored thereon, wherein the program implements the steps of any one of the above methods when executed by a processor.

[0029] The present invention also provides an integral blade ring for an aero-engine, which is designed using any of the above-mentioned integral blade ring finishing methods based on on-machine measurement for controlling tool marks.

[0030] Beneficial effects of the present invention:

[0031] The present invention is based on a method for controlling the tool marks in the finishing of an integral blade ring based on on-machine measurement. The method measures the machined side of the blade before flipping to obtain the contour allowance that needs to be compensated, and measures the machined side after flipping to obtain the angular error of flipping and clamping. The angular position of the blade ring after flipping and clamping is adjusted according to the angular error, and the unmachined side is processed according to the tool path parameters of the adjusted unmachined side. The present invention can effectively control the tool marks in the finishing of the integral blade ring, significantly reduce the number of trial cutting processes, and greatly improve the processing efficiency.

[0032] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the following preferred embodiments are specifically cited and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 is a schematic diagram of the integral leaf ring of the present invention;

[0034] Figure 2 Schematic diagram of the tool mark control method for finishing the integral blade ring based on on-machine measurement according to the present invention;

[0035] Figure 3 is a schematic diagram of the first set of measurement points of the present invention;

[0036] Figure 4 The actual blade profile curve and the theoretical blade profile curve obtained by fitting according to the present invention are:

[0037] Figure 5 is a schematic diagram of the second set of measurement points of the present invention;

[0038] Figure 6 The present invention is a blade ring blade profile processed by the integral blade ring finishing joint mark control method based on on-machine measurement.

[0039] Marking instructions: 1. Shroud; 2. Between hubs; 3. Blades. DETAILED DESCRIPTION

[0040] The present invention will be further described below with reference to the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it. However, the embodiments are not intended to limit the present invention.

[0041] Example 1

[0042] like Figure 2 As shown, this embodiment discloses a method for controlling tool marks during finishing of an integral blade ring based on on-machine measurement, the method comprising the following steps:

[0043] S1. Plan the on-machine measurement path of the machined side on the cross section of the blade to obtain the theoretical coordinates of the first set of measurement points, and then measure to obtain the actual coordinates of the first set of measurement points; Figure 3 , where the black dots are the first set of measurement points.

[0044] Optionally, an on-machine measurement path of the machined side is planned on multiple cross sections of the blade, measurement points are planned on the multiple cross sections, and all the measurement points are combined to obtain a first group of measurement points.

[0045] S2. Calculate the error between the theoretical coordinates and the actual coordinates of the first set of measurement points to obtain the contour allowance of the machined side, and adjust the tool path parameters of the unmachined side according to the contour allowance of the machined side;

[0046] Specifically, step S2 includes: calculating the error between the theoretical coordinates and the actual coordinates of the first group of measurement points to obtain a group of error values, obtaining the contour allowance of the processed side according to the average value of the group of error values, and adjusting the tool path parameters of the unprocessed side according to the contour allowance of the processed side; or, obtaining the contour allowance of the processed side according to the average value of the maximum and minimum values ​​in a group of error values, and adjusting the tool path parameters of the unprocessed side according to the contour allowance of the processed side. Figure 4 , where the solid line is the blade profile curve obtained by fitting the theoretical coordinate curve of the first set of measurement points, and the dotted line is the blade profile curve obtained by fitting the actual coordinates of the first set of measurement points.

[0047] Specifically, the tool path allowance of the unmachined side is adjusted according to the contour allowance of the machined side (for example: if the actual blade profile of the machined side is too thick, a negative allowance is applied to the tool path of the unmachined side so that the unmachined side is no longer too thick after machining). The tool path parameters include the cutting depth and width of the tool path, the machining feed rate F, etc.

[0048] S3. Turn the blade ring over and clamp it;

[0049] Specifically, the bling is flipped over and clamped, and positioned according to angular features. An angular feature is a feature on the bling that determines angular position. For example, a through-hole on the end face of the bling component determines angular position during both front and back machining (a pin on the fixture passes through the hole). This feature is called an angular determining feature. Similar features include angular grooves, etc.

[0050] S4. Plan the on-machine measurement path of the processed side on the blade base and blade back to obtain the theoretical coordinates of the second set of measurement points, and measure to obtain the actual coordinates of the second set of measurement points; the distribution of the second set of measurement points is as follows: Figure 5Because after turning over, the tool axis avoidance problem needs to be considered when measuring the machined side, so there is no need to measure the complete blade profile. It is only necessary to arrange n measuring points (p1, p2, ..., p n )

[0051] S5. Calculate the angular error of the blade ring after turning over based on the theoretical coordinates and actual coordinates of the second set of measurement points;

[0052] Specifically, assume that there is a rotation transformation T A , so that the actual coordinates of the second set of measurement points undergo a rotation transformation T A After that, the sum of the squares of the distances between the theoretical coordinates of the second set of measurement points is minimized, which can be expressed by the mathematical relationship:

[0053]

[0054] Among them, the n theoretical measurement points (p1, p2, ..., p n ), the corresponding n measured points are (p′1, p′2, ..., p′ n ).

[0055] Then the rotation transformation T A is the optimal transformation of the blade ring from the actual angular position to the theoretical angular position; solve the rotation transformation T A , and get the angular error.

[0056] Because the angular rotation transformation T A is the rotation transformation around the Z axis, so the rotation transformation T A for:

[0057]

[0058] Where α is the angular error.

[0059] Optionally, a classic ICP algorithm is used to solve the rotation transformation. Since the ICP algorithm is an existing technology, it will not be described in detail here.

[0060] S6. Adjust the angular position of the blade ring after turning over and clamping according to the angular error; that is, rotate the workpiece coordinate system around the blade ring rotation axis on the machine tool, and the rotation angle is α.

[0061] S7. Process the unprocessed side according to the adjusted tool path parameters of the unprocessed side.

[0062] In order to verify the effectiveness of the present invention, the blade ring is machined using the overall blade ring finishing tool mark control method based on on-machine measurement in this embodiment, and the steps are as follows:

[0063] (1) On some sections of the blade, plan the on-machine measurement path of the machined side. Assume that 50 theoretical measurement points are planned: (p1, p2, ..., p 50 ), the measurement diagram of one of the cross sections is as follows Figure 3 As shown, a measurement NC program is generated, and measurement is performed in situ (without disassembly after machining) to obtain measurement results;

[0064] (2) Analysis of the processed side blade profile

[0065] a. The measured values ​​of 50 measurement points (p'1, p'2, ..., p' 50 ) can be fitted to obtain the actual blade profile curve, such as Figure 4 As shown;

[0066] b. Calculate 50 theoretical measurement points (p1, p2, ..., p 50 ) and its actual value (p′1, p′2, ..., p′ 50 ) between the maximum and minimum errors min and max; the maximum error calculated in this embodiment is max=0.09, and the minimum error is min=-0.05.

[0067] c. The process personnel obtain the contour allowance of the machined side by the average value of the maximum and minimum errors, and adjust the tool path parameters of the unmachined side according to the contour allowance of the machined side;

[0068] (3) Flip-over clamping: After one side is processed and in-situ measured, the operator flips over the blade ring and clamps it and positions it according to the theoretical angular features;

[0069] (4) After turning over and clamping, measure the processed side: appropriately arrange 10 measuring points (p1, p2, ..., p 10 ), the distribution diagram of measurement points is as follows Figure 5 As shown, a measurement NC program is generated and executed to obtain measurement results.

[0070] (5) Calculation of the angular deviation of the flip: Assume that there are 10 theoretical measurement points (p1, p2, ..., p 10 ), the 10 measured points corresponding to it are (p′1, p′2, ..., p′ 10 ) The angular deviation after the blade ring is turned over is calculated using these two sets of points. The angular deviation α calculated according to the formula is 0.12°.

[0071] (6) Processing the unprocessed side

[0072] a. The machine operator can adjust the angular position of the bale ring after flipping and clamping based on the α = 0.12° angle calculated in step 5, and rotate the machining coordinate system on the machine tool by an angle of 0.12°.

[0073] b. The process personnel can adjust the tool path parameters according to the contour curve of the processed side obtained by measurement and analysis in step 2, and then process the unprocessed side to complete the finishing of the blade ring. Figure 6 shown.

[0074] The present invention is based on a method for controlling the tool marks in the finishing of an integral blade ring based on on-machine measurement. The method measures the machined side of the blade before flipping to obtain the contour allowance that needs to be compensated, and measures the machined side after flipping to obtain the angular error of flipping and clamping. The angular position of the blade ring after flipping and clamping is adjusted according to the angular error, and the unmachined side is processed according to the tool path parameters of the adjusted unmachined side. The present invention can effectively control the tool marks in the finishing of the integral blade ring, significantly reduce the number of trial cutting processes, and greatly improve the processing efficiency.

[0075] Example 2

[0076] This embodiment discloses a tool mark control system for finishing of an integral blade ring based on on-machine measurement, which includes:

[0077] A first path planning and measurement module is used to plan an on-machine measurement path of the machined side on the cross section of the blade, obtain theoretical coordinates of a first set of measurement points, and perform measurements to obtain actual coordinates of the first set of measurement points;

[0078] an error calculation module, for calculating the error between the theoretical coordinates and the actual coordinates of the first set of measurement points to obtain the contour allowance of the machined side, and adjusting the tool path parameters of the unmachined side according to the contour allowance of the machined side;

[0079] The second path planning and measurement module is used to plan the on-machine measurement path of the machined side on the blade base and blade back after the blade ring is turned over and clamped, obtain the theoretical coordinates of the second set of measurement points, and measure and obtain the actual coordinates of the second set of measurement points;

[0080] An angular error calculation module, used to calculate the angular error after the blade ring is turned over based on the theoretical coordinates and actual coordinates of the second set of measurement points;

[0081] The processing module is used to adjust the angular position of the blade ring after flipping and clamping according to the angular error, and then process the unprocessed side according to the adjusted tool path parameters of the unprocessed side.

[0082] The integral blade ring finishing joint mark control system based on on-machine measurement in the embodiment of the present invention is used to implement the aforementioned integral blade ring finishing joint mark control method based on on-machine measurement. Therefore, the specific implementation method of the system can be seen in the embodiment part of the integral blade ring finishing joint mark control method based on on-machine measurement in the previous article. Therefore, its specific implementation method can refer to the description of the corresponding above-mentioned method embodiment, and will not be elaborated here.

[0083] In addition, since the integral blade ring finishing joint mark control system based on on-machine measurement in this embodiment is used to implement the aforementioned integral blade ring finishing joint mark control method based on on-machine measurement, its function corresponds to that of the above method and will not be repeated here.

[0084] Example 3

[0085] This embodiment discloses an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, the steps of the method for controlling tool marks in integral blade ring finishing based on on-machine measurement described in the first embodiment are implemented.

[0086] Example 4

[0087] This embodiment discloses a computer-readable storage medium having a computer program stored thereon. When the program is executed by a processor, the steps of the method for controlling tool marks during the finishing of an integral blade ring based on on-machine measurement described in the first embodiment are implemented.

[0088] Example 5

[0089] This embodiment discloses an integral blade ring for an aero-engine, which is manufactured by using the integral blade ring finishing tool mark control method based on on-machine measurement described in the first embodiment.

[0090] The above embodiments are merely preferred embodiments for the purpose of fully illustrating the present invention, and the scope of protection of the present invention is not limited thereto. Equivalent substitutions or modifications made by those skilled in the art based on the present invention are all within the scope of protection of the present invention. The scope of protection of the present invention shall be subject to the claims.

Claims

1. A method for controlling tool marks in finishing of an integral blade ring based on on-machine measurement, characterized in that: The following steps are involved: S1. Planning an on-machine measurement path of the machined side on the cross section of the blade to obtain theoretical coordinates of a first set of measurement points, and performing measurements to obtain actual coordinates of the first set of measurement points; S2. Calculate the error between the theoretical coordinates and the actual coordinates of the first set of measurement points to obtain the contour allowance of the machined side, and adjust the tool path parameters of the unmachined side according to the error; S3. Turning the leaf ring over and clamping it; including: turning the leaf ring over and clamping it, and positioning it according to the angular feature; wherein the angular feature is a feature on the leaf ring that can determine the angular position; S4. Planning an on-machine measurement path for the machined side of the blade base and blade back to obtain theoretical coordinates of a second set of measurement points, and performing measurements to obtain actual coordinates of the second set of measurement points; S5. Calculate the angular error of the blade ring after turning over based on the theoretical coordinates and actual coordinates of the second set of measurement points; S6. Adjust the angular position of the blade ring after turning over and clamping according to the angular error; S7. Process the unprocessed side according to the adjusted tool path parameters of the unprocessed side.

2. The method for controlling tool marks during finishing of an integral blade ring based on on-machine measurement according to claim 1, characterized in that: Step S2 includes: calculating the error between the theoretical coordinates and the actual coordinates of the first group of measurement points to obtain a group of error values, obtaining the contour allowance of the machined side according to the average value of the group of error values, and adjusting the tool path parameters of the unmachined side according to the contour allowance of the machined side; or, obtaining the contour allowance of the machined side according to the average value of the maximum and minimum values ​​in a group of error values, and adjusting the tool path parameters of the unmachined side according to the contour allowance of the machined side.

3. The method for controlling tool marks during finishing of an integral blade ring based on on-machine measurement according to claim 1, characterized in that: Step S5 includes: Assume there is a rotation transformation , so that the actual coordinates of the second set of measurement points are transformed by rotation After that, the sum of the squares of the distances between the theoretical coordinates of the second set of measurement points is the smallest, then the rotation transformation The optimal transformation of the blade ring from the actual angular position to the theoretical angular position; solve the rotation transformation , and get the angular error.

4. The method for controlling tool marks during finishing of an integral blade ring based on on-machine measurement according to claim 3, characterized in that: Because the angular rotation transformation is a rotation transformation around the Z axis, so the rotation transformation for: in, is the angular error.

5. The method for controlling tool marks during finishing of an integral blade ring based on on-machine measurement according to claim 1, characterized in that: In step S1 , an on-machine measurement path of the machined side is planned on multiple cross sections of the blade, measurement points are planned on the multiple cross sections, and all the measurement points are combined to obtain a first group of measurement points.

6. The control system for the joint marks of the integral blade ring finishing process based on on-machine measurement is characterized by: include: A first path planning and measurement module is used to plan an on-machine measurement path of the machined side on the cross section of the blade, obtain theoretical coordinates of a first set of measurement points, and perform measurements to obtain actual coordinates of the first set of measurement points; an error calculation module, for calculating the error between the theoretical coordinates and the actual coordinates of the first set of measurement points to obtain the contour allowance of the machined side, and adjusting the tool path parameters of the unmachined side according to the contour allowance of the machined side; The second path planning and measurement module is used to flip and clamp the blade ring. The module includes: flipping and clamping the blade ring, and positioning it according to angular features; wherein the angular features are features on the blade ring that can determine the angular position; after the blade ring is flipped and clamped, planning an on-machine measurement path on the blade base and blade back of the blade on the machined side to obtain the theoretical coordinates of the second set of measurement points, and performing measurements to obtain the actual coordinates of the second set of measurement points. An angular error calculation module, used to calculate the angular error after the blade ring is turned over based on the theoretical coordinates and actual coordinates of the second set of measurement points; The processing module is used to adjust the angular position of the blade ring after flipping and clamping according to the angular error, and then process the unprocessed side according to the adjusted tool path parameters of the unprocessed side.

7. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the steps of the method for controlling tool marks in integral blade ring finishing based on on-machine measurement as described in any one of claims 1 to 5 are implemented.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method for controlling tool marks in integral blade ring finishing based on on-machine measurement according to any one of claims 1 to 5 are implemented.

9. An integral blade ring of an aero-engine, characterized in that: The blade ring is machined by using the integral blade ring finishing joint mark control method based on on-machine measurement as described in any one of claims 1-5.

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