An aircraft skin dimple precise control method based on trial knife compensation

Abstract

The application discloses a kind of based on test knife compensation's aircraft skin dimple depth accurate control method, based on the error generated when tool is loaded and actual dimple depth, secondary correction is carried out to hole forming processing parameter, so that the dimple depth of skin connecting piece is in controllable range, avoid the overage caused by dimple too deep or too shallow causes product scrapping or secondary processing, guarantee product hole forming dimple depth to meet demand.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of counterbore machining, and relates to an aircraft skin hole depth precise control method based on trial tool compensation. BACKGROUND

[0002] Most of the aircraft outer covering part covers and skin connecting parts are countersunk parts, and the connecting part holes are mostly countersunk holes. The counterbore depth of the connecting part hole directly affects the connecting strength and fatigue life of the aircraft.

[0003] At present, the digital automatic hole making technology is more and more widely applied in the field of aircraft assembly. The digital hole making system uses the preset trajectory production code after simulation to make the main shaft drive the tool to feed and move to make holes and counterbores on the aircraft structure. Theoretically, the operation process is as follows: automatic tool changing of the main shaft, automatic tool setting, movement to the working position, adjustment of the attitude of the main shaft unit, hole making and counterbore making of the main shaft normal feed. Before the automatic hole making of the digital hole making system, we can obtain the theoretical coordinates of the to-be-made hole point from the theoretical model, but the theoretical coordinates are the theoretical coordinates of the hole point in the aircraft coordinate system and the lamination information.

[0004] However, in the actual counterbore process, due to the error in the tool mounting of the main shaft, the relative position of the tool in the coordinate system is offset, so that the tool cannot make holes according to the preset feed value. If the final feed amount is too large, the risk of over-deep counterbore will be caused, and if the final feed amount is too small, the connecting part cannot be put in, and manual secondary processing is required, which affects the hole making efficiency.

[0005] In summary, in order to ensure that the counterbore machining depth meets the requirements and to ensure efficient task completion, an aircraft skin hole depth precise control method based on trial tool compensation is urgently needed. SUMMARY

[0006] The purpose of the present application is to provide an aircraft skin hole depth precise control method based on trial tool compensation, which can automatically select machining tools and machining parameters by identifying the lamination thickness and material, and perform secondary correction on the parameters through trial tool compensation to ensure that the product hole depth meets the requirements.

[0007] The present application is realized by the following technical solutions:

[0008] An aircraft skin hole depth precise control method based on trial tool compensation, comprising the following steps:

[0009] Step S1, establishing a product model, and extracting product connection information from the product model;

[0010] Step S2, classifying the products according to the product connection information, and planning the same type of machining tool for the same type of product, and matching the corresponding machining tool parameters;

[0011] Step S3, calculating the product's hole-making processing parameters based on the product connection information and the processing tool parameters;

[0012] Step S4: selecting a corresponding machining tool according to the hole making machining parameters to perform countersinking test cutting on the trial cut block, and correcting the countersinking depth of the machining tool according to the actual countersinking depth value to obtain a corrected countersinking depth value;

[0013] Step S5: Perform secondary countersinking trial cutting on the trial block using a machining tool according to the countersink correction depth value, detect the actual countersink depth value of the secondary countersinking trial cutting, and end the trial cutting if the actual countersinking depth value of the secondary countersinking trial cutting meets the standard; if the actual countersinking depth value of the secondary countersinking trial cutting does not meet the standard, correct the hole making processing parameters in step S3, and repeat step S4 according to the corrected hole making processing parameters until the actual countersinking depth value of the secondary countersinking trial cutting meets the standard.

[0014] In order to better implement the present invention, further, the product connection information includes spot facing hole position information, laminated material information, and laminated thickness information.

[0015] In order to better implement the present invention, further, the processing tool parameters include material feature codes and laminate thickness codes, and the products with the same laminate material information are divided into the same material feature codes, and the products with laminate thickness information in the same laminate thickness range are divided into the same laminate thickness codes.

[0016] In order to better implement the present invention, further, the calculation formula of the hole making processing parameters is:

[0017]

[0018] in: ; ; ; Represents the hole making parameter function; Indicates the spindle speed of the machining tool; Indicates the spindle feed rate of the machining tool; Indicates the product pressing force; i indicates the material characteristic code; j indicates the laminate thickness code; H indicates the laminate thickness.

[0019] In order to better implement the present invention, further, the machining tool parameters include the machining tool blade length, and the calculation formula of the machining tool blade length is:

[0020] ;

[0021] in: Indicates the tool blade length of the machining tool with material feature code i and stack thickness code j; H represents the stack thickness; M represents the countersink drilling depth.

[0022] In order to better realize the present application, further, the calculation formula of the counterbore correction depth value is:

[0023] ;

[0024] Wherein: represents the correction error value; represents the set counterbore depth value of the machining tool; represents the actual counterbore depth value of the counterbore trial cutting of the machining tool; represents the counterbore correction depth value.

[0025] In order to better realize the present application, further, in the step S5, according to the counterbore correction depth value, the machining tool is used to carry out k times of trial cutting on the trial cutting block, k≥5, and the actual counterbore depth value obtained after each trial cutting is recorded;

[0026] If , the trial cutting is ended;

[0027] If , the hole-making machining parameter in the step S3 is corrected, and the step S4 is re-performed according to the corrected hole-making machining parameter until the actual counterbore depth value of the second counterbore trial cutting reaches the standard;

[0028] Wherein: represents the actual counterbore depth value of the kth trial cutting; represents the minimum allowable value of the counterbore depth; represents the maximum allowable value of the counterbore depth.

[0029] In order to better realize the present application, further, the correction of the hole-making machining parameter in the step S5 specifically includes:

[0030] If , the machining tool spindle speed is corrected; , , ;

[0031] If , the machining tool spindle feed amount is corrected; , , ;

[0032] Wherein: represents the corrected machining tool spindle speed; represents the corrected machining tool spindle feed amount; represents the corrected product pressing force.

[0033] Compared with the prior art, the present application has the following advantages and beneficial effects:

[0034] The present application uses a trial cutting method, based on the error generated when the tool is installed and the actual dimple depth, to make secondary correction to the hole forming processing parameters, so that the dimple depth of the skin connector is within a controllable range, avoiding product rejection or secondary processing caused by excessive dimple depth or excessive dimple depth. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 Flowchart of the aircraft skin dimple depth control method. DETAILED DESCRIPTION

[0036] The following detailed description is exemplary and is intended to provide further explanation of the present application. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

[0037] It should be noted that the terms used herein are only for the purpose of describing specific embodiments, and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless otherwise explicitly stated by the present application, the singular form is also intended to include the plural form, and in addition, it should be understood that when the terms "comprise" and / or "include" are used in the specification, they indicate the presence of a feature, step, operation, device, component and / or combination thereof.

[0038] For the convenience of description, if "up", "down", "left" and "right" appear in the present application, they only mean the same as the up, down, left and right directions of the drawings themselves, and do not limit the structure, but only for the convenience of describing the present application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0039] Term explanation part: The terms "mounting", "connection", "connection", "fixing" and the like in the present application should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected, it can be directly connected, or it can be indirectly connected through an intermediate medium, it can be the internal connection of two elements, or the interaction relationship between two elements, for those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0040] Example 1

[0041] The aircraft skin dimple depth control method based on trial cutting of the present embodiment, as shown in Figure 1 includes the following steps:

[0042] Step S1, establish product model, extract product connection information through product model;

[0043] Step S2, classifying products according to product connection information, and planning the same kind of machining tool for products of the same class and matching corresponding machining tool parameters;

[0044] Step S3, calculating the hole machining parameter of the product according to the product connection information and the machining tool parameter;

[0045] Step S4, selecting the corresponding machining tool according to the hole machining parameter to perform a dimple test cut on the test block, correcting the dimple depth of the machining tool through the actual dimple depth value, and obtaining a dimple correction depth value;

[0046] Step S5, performing a second dimple test cut on the test block using the machining tool according to the dimple correction depth value, detecting the actual dimple depth value of the second dimple test cut, if the actual dimple depth value of the second dimple test cut meets the standard, the test cut is ended, if the actual dimple depth value of the second dimple test cut does not meet the standard, the hole machining parameter in step S3 is corrected, and step S4 is performed again according to the corrected hole machining parameter, until the actual dimple depth value of the second dimple test cut meets the standard.

[0047] The product connection information includes dimple hole position information, laminated material information, and laminated thickness information, wherein the dimple hole position information includes the three-axis coordinates of the center of the dimple hole and the normal vector of the machining surface where the dimple hole is located, the laminated material information includes the composite material grade or the metal material grade of the product, and the laminated thickness information includes the number of laminations and the single-layer thickness of each lamination, and the total thickness of the laminations is equal to the sum of the single-layer thicknesses of all the laminations.

[0048] The machining tool parameters include material characteristic codes and lamination thickness codes, products with the same laminated material information are divided into the same material characteristic code, and products in the same lamination thickness interval are divided into the same lamination thickness code.

[0049] The calculation formula of the hole machining parameter is:

[0050]

[0051] Wherein: ; ; ; represents the hole machining parameter function; represents the machining tool spindle speed; represents the machining tool spindle feed amount; represents the product pressing force; i represents the material characteristic code; j represents the lamination thickness code; H represents the lamination thickness.

[0052] i=1 represents that the corresponding material is titanium alloy, i=2 represents that the corresponding material is composite material, and i=3 represents that the corresponding material is aluminum alloy.

[0053] The machining tool parameter includes a machining tool edge length, and a calculation formula of the machining tool edge length is:

[0054] ;

[0055] Wherein: represents a machining tool edge length of a machining tool with a material characteristic code i and a lamination thickness code j; H represents a lamination thickness; and M represents a spot drilling penetration depth.

[0056] A calculation formula of the spot correction depth value is:

[0057] ;

[0058] Wherein: represents a correction error value; represents a set spot depth value of a machining tool; represents an actual spot depth value of a spot test cut of a machining tool; represents a spot correction depth value.

[0059] In the step S5, the machining tool is used for k times of test cutting on the test block according to the spot correction depth value, k≥5, and actual spot depth values obtained after each test cutting are recorded; for example, the machining tool is used for 5 times of test cutting on the test block according to the spot correction depth value, and actual spot depth values obtained after each test cutting are recorded as , , , , ,

[0060] If , the test cutting is ended;

[0061] If any value in , , , , does not fall into , the hole machining parameter in the step S3 is corrected, and the step S4 is performed again according to the corrected hole machining parameter until the actual spot depth value of the second spot test cutting reaches the standard;

[0062] Wherein: represents an actual spot depth value of the kth test cutting; represents a minimum allowable value of the spot depth; represents a maximum allowable value of the spot depth.

[0063] The correction of the hole machining parameter in the step S5 specifically includes:

[0064] If then , , ;

[0065] If then , , ;

[0066] wherein: represents the corrected machining tool spindle speed; represents the corrected machining tool spindle feed; represents the corrected product pressing force.

[0067] The above merely describes the preferred embodiments of the present application, and is not intended to limit the present application in any form. Any simple modification or equivalent change of the above embodiments according to the technical essence of the present application shall fall within the protection scope of the present application.

Claims

1. A method for accurately controlling the depth of aircraft skin dimples based on tool trial compensation, characterized in that: The following steps are involved: Step S1: Create a product digital model and extract product connection information through the product digital model; Step S2: Classify products according to product connection information, plan the same type of processing tools for products of the same type, and match corresponding processing tool parameters; Step S3, calculating the product's hole-making processing parameters based on the product connection information and the processing tool parameters; Step S4: selecting a corresponding machining tool according to the hole-making machining parameters to perform countersinking on the trial-cut block, and correcting the countersinking depth of the machining tool according to the actual countersinking depth value to obtain a corrected countersinking depth value; Step S5: Perform secondary countersinking trial cutting on the trial block using a machining tool according to the countersink correction depth value, detect the actual countersink depth value of the secondary countersinking trial cutting, and end the trial cutting if the actual countersinking depth value of the secondary countersinking trial cutting meets the standard; if the actual countersinking depth value of the secondary countersinking trial cutting does not meet the standard, correct the hole making processing parameters in step S3, and repeat step S4 according to the corrected hole making processing parameters until the actual countersinking depth value of the secondary countersinking trial cutting meets the standard.

2. The method for accurately controlling the dimple depth of an aircraft skin based on tool trial compensation according to claim 1 is characterized in that: The product connection information includes spot facing hole position information, laminate material information, and laminate thickness information.

3. The method for accurately controlling the depth of aircraft skin dimples based on tool trial compensation according to claim 2 is characterized in that: The processing tool parameters include material feature codes and laminate thickness codes. Products with the same laminate material information are assigned the same material feature code, and products with laminate thickness information in the same laminate thickness range are assigned the same laminate thickness code.

4. The method for accurately controlling the dimple depth of an aircraft skin based on tool trial compensation according to claim 3 is characterized in that: The calculation formula of the hole making processing parameters is: in: ; ; ; Represents the hole making parameter function; Indicates the spindle speed of the machining tool; Indicates the spindle feed rate of the machining tool; Indicates the product compression force; i Indicates the material feature code; j Indicates the laminate thickness code; H indicates the laminate thickness.

5. The method for accurately controlling the dimple depth of an aircraft skin based on tool trial compensation according to claim 4 is characterized in that: The machining tool parameters include the machining tool blade length, and the calculation formula of the machining tool blade length is: ； in: Indicates that the material feature code is i And the stack thickness code is j The tool blade length of the machining tool; H represents the stacking thickness; M represents the countersink drilling depth.

6. The method for accurately controlling the aircraft skin dimple depth based on tool trial compensation according to claim 5 is characterized in that: The calculation formula of the countersink correction depth value is: ； in: Indicates the corrected error value; Indicates the set countersink depth value of the machining tool; Indicates the actual countersink depth value of the countersink test cut by the machining tool; Indicates the countersink correction depth value.

7. The method for accurately controlling the aircraft skin dimple depth based on tool trial compensation according to claim 6, characterized in that: In step S5, k trial cuts are performed on the trial cut block using a machining tool according to the countersink correction depth value, where k is greater than or equal to 5, and the actual countersink depth value obtained after each trial cut is recorded; like , then the trial cutting is ended; like , then correct the hole-making processing parameters in step S3, and re-perform step S4 according to the corrected hole-making processing parameters until the actual countersink depth value of the secondary countersink trial cutting meets the standard; in: Indicates the actual countersink depth value of the kth trial cutting; Indicates the minimum allowable value of the countersink depth; Indicates the maximum allowable countersink depth.

8. The method for accurately controlling the aircraft skin dimple depth based on tool trial compensation according to claim 7 is characterized in that: The step S5 of correcting the hole making parameters specifically includes: like ,but , , ; like ,but , , ; in: Indicates the corrected spindle speed of the machining tool; Indicates the corrected spindle feed rate of the machining tool; Indicates the corrected product clamping force.

Images