A hat-type test piece for drilling and countersinking holes in aircraft skin

Abstract

The application discloses a cap type test cut piece for aircraft skin hole and counterbore machining, relates to the technical field of machining, and comprises a test cut body, the inner side of the test cut body is hollow, the test cut body has a horizontal reference surface and eight test cut surfaces which are arranged around the reference surface, and the test cut surfaces are arranged at an angle with the reference surface and expand outwardly. The test cut can realize full coverage of the direction of the law of error, the digital equipment positioning accuracy, actuator accuracy and the like can be inversely deduced through the hole and counterbore measurement results, and the machine tool acceptance and test cut verification work of the digital hole and counterbore machining equipment of the aircraft skin can be realized.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of machining, in particular to a cap-shaped trial cutting piece for drilling and counterboring of an aircraft skin. BACKGROUND

[0002] In aircraft structure assembly, drilling and counterboring are mainly used, according to the stealth requirement of an aircraft, the shape changes cause the normal directions of holes to be different, and in the drilling and counterboring process, feeding needs to be performed along the normal direction after positioning, and the current digital drilling and counterboring equipment is mainly designed by using a spindle feeding execution mechanism, and the traditional S-shaped trial cutting piece and NAS trial cutting piece cannot achieve the purpose of verifying the manufacturing precision of the drilling and counterboring equipment. SUMMARY

[0003] The main purpose of the application is to provide a cap-shaped trial cutting piece for drilling and counterboring of an aircraft skin, and to solve the problem that the traditional trial cutting piece cannot verify the manufacturing precision of the digital drilling and counterboring equipment using the spindle feeding.

[0004] The technical scheme adopted by the application is as follows:

[0005] A cap-shaped trial cutting piece for drilling and counterboring of an aircraft skin comprises a trial cutting body, the inside of the trial cutting body is hollow, the trial cutting body has a horizontal reference surface and eight trial cutting surfaces arranged around the reference surface, and the trial cutting surfaces and the reference surface are arranged at an included angle and expand outward.

[0006] Optionally, the trial cutting body comprises a support frame in a cap shape, the support frame comprises a brim support part, a tip support part and a top support part, the tip support part is arranged around the top support part, and the brim support part is formed at one end of the tip support part away from the top support part.

[0007] Optionally, the included angle between the top support part and the tip support part is 105 degrees, and the included angle between the tip support part and the brim support part is 165 degrees.

[0008] Optionally, a reference plate and sixteen trial cutting plates are arranged on the support frame, the reference plate is arranged on the top support part, eight of the trial cutting plates are evenly arranged on the tip support part, and the remaining eight of the trial cutting plates are evenly arranged on the brim support part.

[0009] Optionally, the reference plate and the trial cutting plates are detachably connected with the support frame.

[0010] Optionally, the reference plate and the trial cutting plates are connected with the support frame through bolts.

[0011] Optionally, the thickness of the test cutting plate is not greater than 10mm.

[0012] Optionally, the test cutting plate is 1-3 layers.

[0013] Optionally, the center of the reference plate is provided with an origin hole.

[0014] Optionally, the thickness of the support frame is 8-10mm, and the height is 4-6mm.

[0015] Compared with the prior art, the application has the following beneficial effects:

[0016] The cap-shaped test cutting piece for the hole and counterbore of the aircraft skin provided in the application has the following advantages: the test cutting piece is suitable for the hole and counterbore test cutting operation due to the hollowed test cutting piece, the test cutting body has a horizontal reference surface and eight test cutting surfaces arranged around the reference surface, the test cutting surfaces and the reference surface are arranged at an angle and expand outward, so that the test cutting piece can meet the test cutting of all angle regions such as the opening angle and the closing angle of the rotary coordinates of the five-coordinate machine tool, the positioning accuracy of each synthesized angle can be accurately detected, the hole is drilled by the actuator, the normal loss of the hole can be obtained by the three-coordinate measuring machine or the structured light scanning after the test cutting is completed, the measurement normal loss and the theoretical normal loss can be decomposed into each positioning coordinate system to obtain the comprehensive deviation of the actuator, and the comprehensive deviation can be used to evaluate the positioning accuracy and the linkage accuracy of the equipment. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 It is a top view of the S-shaped test cutting piece;

[0018] Figure 2 It is a structural schematic diagram of NAS-979;

[0019] Figure 3 It is a three-dimensional structural schematic diagram of the cap-shaped test cutting piece for the hole and counterbore of the aircraft skin provided in the application under one perspective;

[0020] Figure 4 It is a planar structural schematic diagram of the cap-shaped test cutting piece for the hole and counterbore of the aircraft skin provided in the application under one perspective

[0021] Figure 5 It is a structural schematic diagram of the support frame;

[0022] Figure 6 It is an angle coverage diagram of the cap-shaped test cutting piece for the hole and counterbore of the aircraft skin provided in the application during test cutting;

[0023] Figure 7 It is a state diagram of the main shaft during the hole drilling of the cap-shaped test cutting piece for the hole and counterbore of the aircraft skin provided in the application;

[0024] Figure 8 An effect picture after the hat-shaped trial cutting piece for aircraft skin hole reaming is trial cut according to the embodiment of the present application.

[0025] Label explanation in the drawing:

[0026] 100-trial cutting main body, 101-support frame, 102-trial cutting plate, 103-reference plate, 200-main shaft, 1010-cap top support part, 1011-cap tip support part, 1012-cap edge support part. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0028] It should be noted that all directional indications, such as up, down, left, right, front, back, etc., in the embodiments of the present application are only used to explain the relative positional relationship, movement condition, etc. between components in a certain posture (as shown in the drawings), and if the certain posture changes, the directional indications will also change accordingly.

[0029] In the present application, unless otherwise explicitly specified and limited, the terms "connection", "fixation" and the like should be understood in a broad sense, for example, "fixation" can be fixed connection, or detachable connection, or integral; can be mechanical connection, or electrical connection; can be directly connected, or indirectly connected through an intermediate medium; can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise explicitly limited. 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.

[0030] In addition, if the description of "first", "second" and the like is involved in the embodiments of the present application, the description of "first", "second" and the like is only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first", "second" can be explicitly or implicitly included at least one of the features. In addition, the meaning of "and / or" appearing throughout the text includes three parallel schemes. For example, "A and / or B" includes A scheme, or B scheme, or A and B scheme. In addition, the technical solutions of each embodiment can be combined with each other, but it must be based on the realization of the ordinary skilled in the art. When the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, and is not within the protection scope required by the present application.

[0031] It should be understood that the specific embodiments described herein are only used to explain the present application and not to limit the present application.

[0032] To meet the needs of aerodynamic performance and stealth performance of the aircraft, higher requirements are put forward for the surface shape of the aircraft. At present, the connection of the aircraft mainly adopts riveting form, and a large number of countersunk fasteners are connected. The quality of the countersunk hole used for the connection of the countersunk fastener is the key to affect the performance of the aircraft. It is obviously difficult to meet the needs of the new generation of aircraft by relying on manual work to meet the size measurement of tens of thousands of holes and countersinks. At present, the hole and countersink process of aviation enterprises is gradually changed from manual work to digital equipment processing.

[0033] In the structure assembly, the digital equipment is less, and the precision evaluation currently follows part of the existing conventional numerical control equipment detection scheme, but lacks detection means for special structure and design. In the aspect of precision detection of conventional numerical control equipment, the widely recognized technical achievements at home and abroad are embodied in several existing international standards. The existing technology detects very simple and intuitive single precision index for the geometric precision and positioning precision of machine tool and repeat positioning precision.

[0034] At present, in the acceptance of machine tool dynamic precision, one of the main detection standards is S-shaped test cut piece (as shown in Figure 1 ) developed by AVIC company, mainly used for dynamic precision verification of milling equipment with curved surface change; the other is "general cutting test-NAS series, metal cutting equipment specification" developed by the National Aeronautics and Space Administration in the 1970s, which provides a standard method for checking the multi-axis linkage precision of five-coordinate numerical control milling machine under actual machining condition. The test piece used in this method is called "NAS test cut piece" (as shown in Figure 2 ), mainly used for geometric precision verification of three-coordinate linear feed milling.

[0035] Because the main hole countersinking is mainly used in the aircraft structure assembly, according to the aircraft stealth requirement, the shape change leads to the different normal direction of each hole, and in the process of hole making and countersinking, the feeding along the normal direction is needed after positioning, the trial cutting of the countersinking hole type part needs to penetrate the part, the back of the part needs to be kept hollow and supported by the frame, and currently the NAS trial cutting part and the S-shaped trial cutting part both belong to the back solid support, which cannot meet the requirements of the trial cutting of the countersinking hole type part, and therefore the precision problem of the countersinking hole equipment cannot be known through the traditional NAS trial cutting part and the S-shaped trial cutting part.

[0036] Referring to the drawings Figure 3 The embodiment of the present application provides a cap-shaped trial cutting part for aircraft skin hole countersinking, the trial cutting can realize full coverage of the normal direction, the positioning precision of the digital equipment, the precision of the actuator and the like can be deduced reversely through the measurement results of the hole countersinking, and the machine tool acceptance and trial cutting verification work of the digital hole countersinking equipment of the aircraft skin can be realized. Specifically, the trial cutting part 100 is hollow on the inner side, the trial cutting part 100 has a horizontal reference surface and eight trial cutting surfaces arranged around the reference surface, the trial cutting surfaces are arranged at an angle between the reference surface, and the trial cutting surfaces expand outward from one end in contact with the reference surface to the other end away from the reference surface.

[0037] As can be imagined, when the spindle of the machine tool feeds along the normal vector of the trial cutting surface, the trial cutting part is hollow, so the feeding can be performed through the trial cutting body when countersinking, and since three coordinate surfaces divide the space into eight parts, each part is called a quadrant, and the eight-surface design meets the comprehensive measurement requirements of the eight-quadrant space, so the trial cutting part meets the trial cutting of all angle regions such as the opening angle and the closing angle of the countersinking hole of the five-coordinate machine tool rotary coordinate.

[0038] In the embodiment, referring to Figure 3 , Figure 4 and Figure 5 , the trial cutting part 100 includes a support frame 101, and the support frame 101 is in a cap-shaped structure. The support frame 101 is formed by welding a steel part, the thickness of the support frame 101 is 8mm-10mm, the height is 4mm-6mm, and the length can be adjusted according to the height. As can be imagined, the trial cutting part main body of the eight trial cutting surfaces is assembled by eight surfaces, and the optimal design scheme is a cap type, and the trial cutting part 100 of a spherical structure is relatively complex and difficult to process.

[0039] At the same time, referring to Figure 5As shown, the support frame 101 includes a brim support portion 1012, a tip support portion 1011, and a crown support portion 1010. The brim support portion 1012, the tip support portion 1011, and the crown support portion 1010 are welded together. The tip support portion 1011 is arranged around the crown support portion 1010. The tip support portion 1011 expands outward from the end that contacts the crown support portion 1010 toward the end of the tip support portion 1011 away from the crown support portion 1010. The brim support portion 1012 is formed around the end of the tip support portion 1011 away from the crown support portion 1010. Similarly, the brim support portion 1012 expands outward from the end that contacts the tip support portion 1011 toward the end of the tip support portion 1011 away from the crown support portion 1010. The crown support 1010 and the tip support 1011 form a 105-degree angle, meaning the tip support 1011 has a 15-degree angle with the vertical plane. The tip support 1011 and the brim support 1012 form a 165-degree angle, meaning the brim support 1012 has a 75-degree angle with the vertical plane (e.g., ...). Figure 4 (As shown). Since 15 degrees and 75 degrees are the maximum assembly angles for aerospace components, setting the top support 1010 and tip support 1011 of the test cut body 100 at a 105-degree angle, and the tip support 1011 and brim support 1012 at a 165-degree angle, can verify the various accuracies of the actuator under extreme conditions.

[0040] In this embodiment, the support frame 101 has several mounting frames for mounting test cut plates 102. A reference plate 103 and sixteen test cut plates 102 are mounted within each mounting frame on the support frame 101. The reference plate 103 is located in the hat top support portion 1010. Of the sixteen test cut plates 102, eight are evenly distributed in the hat tip support portion 1011, and the remaining eight are evenly distributed in the hat brim support portion 1012. The thickness of each test cut plate 102 is no greater than 10 mm. See also... Figure 6 As shown, after installing the test cutting plate 102, based on one reference plate 103 and sixteen test cutting plates 102, the test cut piece can achieve the open and closed angle ranges of all coordinate axes. Taking an AB-class coordinateless machine tool as an example, it can realize the countersinking and hole making of 17 AB angle combination surfaces (such as...). Figure 6 (As shown).

[0041] To facilitate the replacement of the test cutting plate 102 and the reference plate 103, in one embodiment, both the reference plate 103 and the test cutting plate 102 are detachably connected to the support frame 101. As a feasible implementation, both the reference plate 103 and the test cutting plate 102 are connected to the support frame 101 by bolts, allowing the support frame 101 to be reused repeatedly; only the test cutting plate 102 and the reference plate 103 need to be removed from the support frame 101 for replacement. Alternatively, the test cutting plate 102 and the reference plate 103 can also be detachably connected to the support frame 101 via a snap-fit ​​connection. For example, several protruding hooks can be provided on the support frame 101, and corresponding locking holes can be provided on the test cutting plate 102 and the reference plate 102. When installing the test cutting plate 102 and the reference plate 103, the locking holes are aligned with the hooks, and the hooks are pressed down to engage with the locking holes, thus fixing the test cutting plate 102 and the reference plate 103.

[0042] In one embodiment, the test cutting plate 102 has 1-3 layers, and correspondingly, the reference plate 103 also has 1-3 layers. Test cutting plates with different numbers of layers can be installed as needed for different stacked hole countersinking and riveting test cutting. At the same time, the reference plate 103 has an origin hole at its center to facilitate the spindle to perform test cutting positioning.

[0043] Similarly, the test cutting plates 102 and the reference plates 103 are detachably connected. As a feasible implementation, the test cutting plates 102 and the reference plates 103 can be connected by bolts. Of course, the test cutting plates 102 and the reference plates 103 can also be connected by snap-fit. This will not be elaborated further here.

[0044] See Figure 7 and Figure 8 As shown, this application provides a cap-shaped test cut for countersinking holes in aircraft skin, and the test cutting process is as follows:

[0045] S1: Replace the skin used for trial cutting on the test cutting body 100. The skin is the test cutting plate and the reference plate.

[0046] S2: Install and fix the test cut body 100 on the digital equipment platform, which is also the machine tool's worktable;

[0047] S3: Hole countersinking is performed using an end effector or a digital equipment spindle;

[0048] S4: Drill holes on the test cut body 100, and measure the quality of the countersink after drilling, including but not limited to hole diameter, hole loss, countersink depth, and coaxiality between the countersink and the hole;

[0049] S5: Evaluate the accuracy of various aspects of the machine tool based on the measurement results;

[0050] In step S2, the trial cutting body 100 can be installed on a digitizing device workbench, and for a lower clamping type counterbore device, it can also be delivered by hand to the main shaft 200 for counterboring.

[0051] In step S3, when the trial cutting model is cut, a hole counterboring program is written, and the origin is selected at the original hole of the reference surface. When the hole counterboring and riveting are manually performed, they can be placed randomly.

[0052] In step S4, a three-coordinate measuring machine is used for measurement, and indicators such as hole diameter, hole method loss, counterbore depth, and coaxiality of the counterbore and the hole are measured.

[0053] In step S5, the measurement method loss and the theoretical method loss are decomposed into each positioning coordinate system, and the comprehensive deviation under the actuator is obtained. The comprehensive deviation can be used to evaluate the positioning accuracy of the end effector, the parallelism of the end effector and the Z-axis, the coaxiality of the anvil mechanism, the spatial positioning accuracy and the repeat positioning accuracy of the nine positions synthesized by the double rotary shafts.

[0054] In summary, the cap-shaped trial cutting piece for aircraft skin hole counterboring provided by the embodiments of the present application has the following main beneficial effects:

[0055] First, the cap-shaped trial cutting piece for aircraft skin hole counterboring provided by the embodiments of the present application meets all angle regions such as open angle and closed angle of a five-coordinate machine tool rotary coordinate, can accurately detect the positioning accuracy of each synthesized angle, and can evaluate the comprehensive precision error of the hole counterboring device after hole making by the actuator.

[0056] Second, the cap-shaped trial cutting piece for aircraft skin hole counterboring provided by the embodiments of the present application can be reused by replacing the trial cutting plate.

[0057] Third, the cap-shaped trial cutting piece for aircraft skin hole counterboring provided by the embodiments of the present application can also be installed with a curved skin with curvature, which is used to meet the processing trial cutting of transformed curved surfaces.

[0058] Fourth, the cap-shaped trial cutting piece for aircraft skin hole counterboring provided by the embodiments of the present application has a simple structure, is easy to manufacture and process, and is simple to clamp and measure, and has strong practicality.

[0059] The above only describes the preferred embodiments of the present application and does not limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A hat-type pilot for use in drilling counterbores in aircraft skin, characterized by, The trial cutting body is hollowed on the inner side, has a horizontal reference surface and eight trial cutting surfaces arranged around the reference surface and outwardly diverging from the reference surface; The trial cutting body comprises a hat-shaped support frame, which comprises a brim support part, a tip support part and a top support part, the tip support part is arranged around the top support part, and the brim support part is formed at one end of the tip support part away from the top support part.

2. A hat-type pilot for use in drilling a countersink in an aircraft skin according to claim 1, characterized in that, The angle between the top support part and the tip support part is 105 degrees, and the angle between the tip support part and the brim support part is 165 degrees.

3. A hat-type pilot for use in countersinking holes in aircraft skin as defined in claim 1, wherein, The support frame is provided with a reference plate and sixteen trial cutting plates, the reference plate is arranged on the top support part, eight of the trial cutting plates are evenly arranged on the tip support part, and the remaining eight trial cutting plates are evenly arranged on the brim support part.

4. A hat-type pilot for use in countersinking holes in aircraft skin according to claim 3, characterized in that, The reference plate and the trial cutting plates are detachably connected with the support frame.

5. A hat-type trial piece for countersinking holes in aircraft skin according to claim 4, characterized in that, The reference plate and the trial cutting plates are connected with the support frame by bolts.

6. A hat-type pilot for use in countersinking holes in aircraft skin as defined in claim 3, wherein, The thickness of the trial cutting plate is not greater than 10 mm.

7. A hat-type pilot for use in countersinking holes in aircraft skin as defined in claim 3 wherein, The trial cutting plate has 1-3 layers.

8. A hat-type pilot for use in countersinking holes in aircraft skin as defined in claim 3, wherein, The reference plate is provided with an origin hole at the center.

9. A hat-type pilot bore for use in countersinking holes in aircraft skin as defined in claim 1 wherein, The thickness of the support frame is 8-10 mm, and the height is 4-6 mm.

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