High-precision drilling method for multi-fork ear type aircraft structure

Abstract

The invention belongs to an aircraft assembly technology, and relates to a high-precision drilling method for a multi-fork ear type aircraft structure. The high-precision rigid clamp has the following advantages in the aspects of improving the product precision of the multi-fork ear type externally-hung beam joint of the helicopter, ensuring the machining quality, improving the production efficiency and the like: the final hole precision is not lower than H8 level; the smooth finish of the hole wall is not lower than Ra1.6; the coaxiality of the front hole and the rear hole of the same fork lug is not less than phi 0.04 mm; the relative position precision of four groups of fork ear type interfaces on the left side and the right side is not lower than 0.1 mm; the number of hole-making stages is reduced by at least 50% compared with a traditional method; the hole making time is reduced by at least 40% compared with a traditional method; the service life of a drilling tool is long, the tool cost is reduced by 95%, and excellent economical efficiency is achieved; the drilling quality is consistent and stable, ergonomics is met, the labor intensity of an operator is low, and operation is convenient. Through long-term application verification, the method has the characteristics of high reliability, stable quality and the like, and has wide popularization and application values.

Description

Technical Field

[0001] The invention belongs to aircraft assembly technology and relates to a high-precision hole making method for a multi-fork ear type aircraft structure. Background Art

[0002] When performing missions, shipborne helicopters will be in a high temperature, high humidity, and high salt environment for a long time, and the multi-fork ear-type external beam joints, which are the key structures of shipborne helicopters, are always exposed. In order to ensure that they have good corrosion resistance, strength, toughness and plasticity, the materials selected are often difficult-to-process materials such as 1Cr17Ni3A martensitic ferritic stainless steel. In the field of helicopter manufacturing, the finishing of large-aperture multi-fork ear-type external beam joints after the assembly of the fuselage structure is a key process. Finishing can ensure the accurate size and smooth surface of the multi-fork ear-type external beam joints, eliminate assembly stress to ensure its subsequent close fit with weapons, and improve the wear resistance and corrosion resistance of the multi-fork ear-type external beam joints, extend their service life, and ensure the reliability and stability of shipborne helicopters during long-term operation. Summary of the invention

[0003] The objects of the present invention are:

[0004] In the traditional process of finishing the multi-fork ear external beam joint, strip-shaped cutting chips are easily generated, which cause scratches on the inner wall of the joint and result in excessive roughness of the hole wall; the processing parameters such as feed speed are not constant, which easily leads to excessive coaxiality of the front and rear holes of the fork ear; the tooling structure is not rigid enough, and the relative position accuracy between the fork ear joints is not easy to guarantee; the multi-fork ear external beam joint has a large aperture, and often adopts 9-level hole making, which has a long cycle and low efficiency. When making holes manually, the operator needs to maintain a special posture and continue to push the air drill forward along the drill template, which is subject to a large reaction force, causing fatigue and injury to the operator's waist and shoulders, which does not meet ergonomics; the cost of the 9-level hole making tool is high and the economy is poor. The above factors restrict the finishing quality and efficiency of the multi-fork ear external beam joint holes of helicopters.

[0005] In view of the above problems, the present invention proposes a high-precision hole making method for multi-fork ear aircraft structure, which combines the application of high-precision, simple and flexible rigid fixture, advanced portable boring and reaming tools, etc., and comprehensively improves the process flow, tool configuration, process parameters, etc., to achieve high-quality and high-efficiency engineering applications, and break through the difficulty of fine processing of multi-fork ear aircraft structure holes.

[0006] The technical solution of the present invention is:

[0007] The present invention proposes a high-precision hole making method for a multi-fork ear aircraft structure, which specifically includes the following steps:

[0008] 1) Product positioning on the rack: The large helicopter component with an integrated multi-fork ear structure is positioned on the rack on a high-precision rigid fixture, which mainly includes a main locator 1, a fork ear locator 2, an equipment drilling template 3, an overall frame 4, and a sliding device 5; the main locator 1 is fixed to the upper part of the overall frame 4; the fork ear locator 2 is fixed to both sides of the overall frame 4; the equipment drilling template 3 is installed on both sides of the overall frame 4, and the sliding device 5 is installed on the lower side of the overall frame 4; the main positioning reference is the upper side structure of the large helicopter component, and the main reduction platform or engine platform is connected to the hole of the main locator 1 and the surface is fitted; the auxiliary positioning is that the initial hole of the fork ear joint is connected to the hole of the fork ear locator 2 and the surface is fitted, and the fork ear locator 2 and the equipment drilling template 3 are driven by the sliding device 5 to reciprocate.

[0009] 2) Inspection before production: Use inspection pins with the diameter of the initial hole of the fork ear structure minus 0.8mm, the diameter of the initial hole minus 1.0mm, and the diameter of the initial hole minus 1.2mm to inspect the coaxiality of the initial hole of the fork ear structure and the two holes of the fork ear locator. The order of using the inspection pins is from large to small, and the assembly error accumulation deviation detection data is recorded for tool adjustment;

[0010] 4) Preparation before production: The tool material is a carbide internally cooled tool with a front guide, which consists of a blade and a tool bar. The front guide diameter of the tool bar of each specification is the same. The rough and fine processing of the hole can be achieved by replacing the blade and tool bar. According to the pre-production inspection data, the tool setting instrument is used to adjust the fine boring tool for the final hole. After the tool is adjusted, the portable boring drill is positioned using the equipment drilling template 3 of the high-precision rigid fixture, and the portable boring drill indexing bayonet is inserted into the guide hole of the equipment drilling template 3. The indexing bayonet is rotated counterclockwise to ensure that the indexing bayonet is locked with the equipment drilling template 3. The portable boring drill is adjusted to the best working posture using the rotary indexing head function;

[0011] 5) High-precision hole making: The hole making path is from left to right and from top to bottom. When making one group of holes, it is necessary to insert positioning pins into the three groups of holes on the same side and at least one group of holes on the opposite side for fixing; four-level hole making is adopted, namely, rough boring correction once, rough boring twice, and fine boring once, with a speed range of 150rpm~200rpm, a feed speed range of 0.02~0.04mm / r, a rough boring cutting range of 0.2mm~0.8mm, and a fine boring cutting range of 0.15mm~0.25mm;

[0012] The main locator 1 is composed of a platform hole locator, a platform surface locator, an extension mechanism, and multiple groups of positioning bolts; the extension mechanism is firmly connected to the overall frame 4, and the platform hole locator and the platform surface locator are firmly connected to the extension mechanism. The extension mechanism is an intermediate structure that connects the upper and lower parts, and multiple groups of positioning bolts are used to connect the product and the platform hole locator.

[0013] The number of the positioning bolts corresponds to the number of platform holes on the product.

[0014] The fork ear locator 2 is composed of a fork ear hole locator, a fork ear surface locator, an extension mechanism, and a series of specification inspection pins. The extension mechanism is firmly connected to the overall frame 4, and the fork ear hole locator and the fork ear surface locator are firmly connected to the extension mechanism. The extension mechanism is an intermediate structure that connects the upper and lower parts; the series of specification inspection pins are used to inspect the connection product and the fork ear hole locator.

[0015] The specifications and quantity of the series of inspection pins are determined based on the diameter and quantity of the processed holes.

[0016] The series specification inspection pin checks the coaxiality of the product and the equipment drilling template 3.

[0017] The equipment drilling template 3 is composed of a drilling template and a supporting structure. One side of the supporting structure is firmly connected to the overall frame 4, and the other side is connected to the drilling template. The supporting structure is an intermediate mechanism used for equipment hole making.

[0018] The overall frame 4 is a steel welded structure, which can safely bear its own weight, the weight of other module structures and the weight of the product, and is firmly connected to the ground and to other module structures.

[0019] The sliding device 5 is composed of a slide rail assembly, an upper / lower positioning support, and a limiter; the upper / lower positioning support is connected to the slide rail assembly and moves back and forth with the slide rail assembly, and the limiter is connected to the overall frame 4 and opens and closes with the upper / lower positioning support to limit the position of the slide rail assembly.

[0020] The number of the fork ear positioners 2 and the equipment drilling template 3 corresponds to the number of the fork ears.

[0021] The advantages of the present invention are:

[0022] The present invention proposes a high-precision hole making method for a multi-fork-ear aircraft structure, which has the following advantages in improving the product precision of the multi-fork-ear external beam joint of a helicopter, ensuring the processing quality and improving the production efficiency: the final hole precision is not less than H8 level; the hole wall finish is not less than Ra1.6; the coaxiality of the front and rear holes of the same fork ear is not less than φ0.04mm; the relative position precision of the four groups of fork-ear interfaces on the left and right sides is not less than 0.1mm; the hole making level is at least reduced by 50% compared with the traditional method; the hole making time is at least reduced by 40% compared with the traditional method; the hole making tool has a long life, reduces the tool cost by 95%, and has excellent economy; the hole making quality is consistent and stable, meets ergonomics, the operator has low labor intensity, and is easy to operate. The method of the present invention has been verified by long-term application, has the characteristics of high reliability and stable quality, and has the value of wide promotion and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is the main view of the high-precision rigid fixture;

[0024] Figure 2This is a top view of the high-precision rigid fixture;

[0025] Figure 3 This is the right view of the high-precision rigid fixture;

[0026] Among them: 1-main locator, 2-fork ear locator, 3-equipment drilling template, 4-integral frame, 5-sliding device. DETAILED DESCRIPTION

[0027] The present invention is further described below in conjunction with the accompanying drawings:

[0028] A high-precision hole making method for a multi-fork ear aircraft structure, specifically comprising the following steps:

[0029] (1) Positioning on the product rack: The large helicopter component with an integrated multi-fork ear structure is positioned on the rack on a high-precision rigid fixture. The high-precision rigid fixture mainly includes a main positioner 1, a fork ear positioner 2, an equipment drilling template 3, an overall frame 4, and a sliding device 5; the main positioner 1 is fixed to the upper part of the overall frame 4; the fork ear positioner 2 is fixed to both sides of the overall frame 4; the equipment drilling template 3 is installed on both sides of the overall frame 4, and the sliding device 5 is installed on the lower side of the overall frame 4; the main positioning reference is the upper side structure of the helicopter large component, and the main reduction platform or engine platform is connected to the hole of the main positioner 1 and the surface is fitted; the auxiliary positioning is the connection between the initial hole of the fork ear joint and the hole of the fork ear positioner 2 and the surface is fitted, and the fork ear positioner 2 and the equipment drilling template 3 are driven by the sliding device 5 to reciprocate.

[0030] (2) Inspection before production: Use inspection pins with the diameter of the initial hole of the fork ear structure minus 0.8mm, the diameter of the initial hole minus 1.0mm, and the diameter of the initial hole minus 1.2mm to inspect the coaxiality of the initial hole of the fork ear structure and the two holes of the fork ear locator. The order of using the inspection pins is from large to small, and the assembly error accumulation deviation detection data is recorded for tool adjustment;

[0031] (3) Preparation before production: The tool material is a carbide internally cooled tool with a front guide, which consists of a blade and a tool bar. The front guide diameter of the tool bar of each specification is the same. The rough and fine processing of the hole can be achieved by replacing the blade and tool bar. According to the pre-production inspection data, the tool setting instrument is used to adjust the fine boring tool of the final hole. After the tool is adjusted, the portable boring drill is positioned using the equipment drilling template 3 of the high-precision rigid fixture, and the portable boring drill indexing bayonet is inserted into the guide hole of the equipment drilling template 3. The indexing bayonet is rotated counterclockwise to ensure that the indexing bayonet is locked with the equipment drilling template 3. The portable boring drill is adjusted to the best working posture using the rotary indexing head function;

[0032] (4) High-precision hole making: The hole making path is from left to right and from top to bottom. When making one group of holes, it is necessary to insert positioning pins into the three groups of holes on the same side and at least one group of holes on the opposite side for fixing. Four-level hole making is adopted, namely, rough boring correction once, rough boring twice, and fine boring once. The speed range is 150rpm~200rpm, the feed speed range is 0.02~0.04mm / r, the rough boring cutting range is 0.2mm~0.8mm, and the fine boring cutting range is 0.15mm~0.25mm.

[0033] (5) Cleaning after hole making: Clean the excess material generated during the hole making process.

[0034] The main positioner (1) is composed of a platform hole positioner, a platform surface positioner, an extension mechanism, and multiple sets of positioning bolts; the extension mechanism is firmly connected to the overall frame 4, and is used to position and connect the platform structure on the product, and is the main positioning mechanism for positioning the product on the shelf. The platform hole positioner and the platform surface positioner are firmly connected to the extension mechanism, and the extension mechanism is an intermediate structure connecting the upper and lower parts. Multiple sets of positioning bolts are used to connect the product and the platform hole positioner. The number of the positioning bolts corresponds to the number of platform holes on the product.

[0035] The fork ear locator 2 is composed of a fork ear hole locator, a fork ear surface locator, an extension mechanism, and a series of specification inspection pins. The extension mechanism is firmly connected to the overall frame 4 and is used to inspect and locate the multi-fork ear structure of the product; the fork ear hole locator and the fork ear surface locator are firmly connected to the extension mechanism, and the extension mechanism is an intermediate structure that connects the upper and lower parts; the series of specification inspection pins are used to inspect the connection between the product and the fork ear hole locator. The specifications and quantity of the series of specification inspection pins are determined according to the processed hole diameter and quantity. The series of specification inspection pins are used to check the coaxiality of the product and the equipment drilling template 3, and the series of specification inspection pins are used to assist in positioning the product.

[0036] The equipment drilling template 3 is composed of a drilling template and a supporting structure. One side of the supporting structure is firmly connected to the overall frame 4, and the other side is connected to the drilling template. The supporting structure is an intermediate mechanism used for equipment hole making.

[0037] The fork ear locator 2 is used in coordination with the equipment drilling template 3. For example, if the series of positioning pins for auxiliary positioning at a certain position on the fork ear locator are removed, the equipment drilling template 3 and the portable boring equipment are used to make holes in the fork ear. After making the holes, the positioning pin at that position is connected. Then the next fork ear hole is made, and the fork ear holes at different positions are made reciprocatingly in sequence. To ensure accuracy, the fork ear locator 2 is not connected to the equipment drilling template 3, and they are independently connected to the overall frame 4.

[0038] The overall frame 4 is a steel welded structure, which can safely bear its own weight, the weight of other module structures and the weight of the product, and is firmly connected to the ground and to other module structures.

[0039] The sliding device 5 is composed of a slide rail assembly, an upper / lower positioning support, and a limiter; the upper / lower positioning support is connected to the slide rail assembly and moves back and forth with the slide rail assembly, and the limiter is connected to the overall frame 4 and opens and closes with the upper / lower positioning support to limit the position of the slide rail assembly.

[0040] Before the product enters the high-precision rigid fixture, the sliding device 5 is used to slide the equipment drilling template 3 to the outside. After the product enters the high-precision rigid fixture, the sliding device 5 is pushed to move the equipment drilling template 3 toward the product. The upper / lower positioning supports of the sliding device 5 are fitted with the limiter. After there is no gap between the fitting surfaces, the upper / lower positioning supports are connected and tightened with the positioning bolts.

[0041] The number of the fork ear positioners 2 and the equipment drilling template 3 corresponds to the number of the fork ears.

[0042] Example

[0043] The integrated weapon hanging beam structure of a certain type of aircraft is located in the middle of the overall frame 4 and the sliding device 5. Taking into account the favorable factors such as the excellent processing of the whole frame forgings, the improvement of connection strength, and the reduction of weight, the product design integrates 8 groups (4 groups on the left and 4 groups on the right, with the final hole accuracy of 5-φ20H8mm and 3-φ24H8mm respectively) of fork-ear integrated weapon hanging beam installation interfaces into the overall frame 4 and the sliding device 5 frame. Different from the separate parts form of the integrated weapon hanging beam installation interfaces of other helicopters, the relative accuracy can be ensured through coordinated assembly. The overall frame 4 and the sliding device 5 frames of a certain type of aircraft are The frame is added to the overall machine, and the overall frame 4 and the sliding device 5 frame are assembled using 4 φ10mm positioning holes on the frame respectively. When the overall frame 4 and the sliding device 5 frame parts are manufactured, the position tolerance of the weapon hanging beam installation interface relative to the positioning holes on the frame is φ0.5mm, and the position tolerance of the overall frame 4 and the sliding device 5 frame tooling locator is φ0.2mm. The error accumulation causes the relative position accuracy of the 4 groups of fork-ear interfaces on the left and right sides to exceed the engineering requirement of 0.1mm. Therefore, the assembly error can only be eliminated by fine processing after the components are assembled to ensure the relative position between the weapon hanging beam installation interfaces.

[0044] Based on the above requirements, the invention applies a high-precision hole making method for a multi-fork ear aircraft structure to ensure assembly quality and efficiency, which specifically includes the following:

[0045] (1) Positioning on the product rack. The large components of the middle fuselage with integrated integral frame 4 and sliding device 5 are positioned on the rack on a high-precision rigid fixture. The high-precision rigid fixture mainly includes a main locator 1, fork ear locators 2 (8 sets, 1 set for each fork ear joint), equipment drilling template 3 (8 sets, 1 set for each fork ear joint), integral frame 4, and sliding device 5 (2 sets, 1 set on each side). The main positioning reference is the hole connection and surface fit between the main reduction platform on the upper side of the middle fuselage and the main locator 1; the auxiliary positioning is the hole connection and surface fit between the initial holes of the 8 groups of fork ear joints and the fork ear locators 2. The sliding device 5 drives the fork ear locators 2 and the equipment drilling template (3) to work reciprocatingly.

[0046] (2) Inspection before production. Use Φ17.7mm, Φ17.5mm, and Φ17.3mm inspection pins to check the coaxiality between the product's Φ18.5mm initial hole and the fork ear locator (2) hole, and use Φ21.7mm, Φ21.5mm, and Φ21.3mm inspection pins to check the coaxiality between the product's Φ22.5 initial hole and the fork ear locator 2 hole. The inspection pins are used in descending order, and the assembly error accumulation deviation detection data is recorded for tool adjustment.

[0047] (3) Preparation before production. The tool is made of carbide internally cooled tool with front guide, which is composed of detachable blade and tool bar. The front guide diameter of each specification of tool bar is the same. The rough and fine processing of the hole can be achieved by replacing the blade and tool bar. The tool setting instrument is used to adjust the φ20mm and φ24mm fine boring tools. The φ20 tool adjustment requirements are: OH (main table) = +0.002mm~+0.005mm, and the difference between BT (sub-table) and the main table is 10±2μm; the φ24 tool adjustment requirements are: OH = +0.023mm-+0.026mm, and the difference between BT (sub-table) and the main table is 10±2μm. After adjusting the tool, use the equipment drilling template 3 to locate the portable boring drill, insert the drill sleeve into the guide hole of the drilling template, rotate the tool counterclockwise, make sure that the drill sleeve hanging ear is locked with the drilling template, and use the rotatable dividing head function to adjust the tool to the best working posture.

[0048] (4) High-precision hole making. During hole making, no other operations may be performed on the machine, and no personnel other than the hole making operator may board the machine. The hole making path is from left to right and from top to bottom. To ensure the stability of the reaming state, when making one group of holes, it is necessary to insert positioning pins into the three groups of holes on the same side and at least one group of holes on the opposite side for fixing. Four-level hole making is adopted, namely, rough boring correction once, rough boring twice, and fine boring once, with a rotation speed of 183rpm, a feed speed of 0.032mm / r, and a rough boring cutting depth of 0.2mm. The hole making sequence for Φ20H8 is: φ18.75mm (rough boring and deviation correction) → φ19.3mm (rough boring) → φ19.8mm (rough boring) → φ20H8 (fine boring); the hole making sequence for Φ24H8 is: φ22.75mm (rough boring and deviation correction) → φ23.3mm (rough boring) → φ23.8mm (rough boring) → φ24H8 (fine boring).

[0049] (5) Cleaning after hole making: Clean the excess material generated during the hole making process.

Claims

1. A high-precision hole making method for a multi-fork ear aircraft structure, characterized in that: The details include: 1) Positioning on the product rack: The large helicopter component with an integrated multi-fork ear structure is positioned on the rack on a high-precision rigid fixture, the high-precision rigid fixture mainly comprising a main positioner (1), a fork ear positioner (2), an equipment drilling template (3), an overall frame (4), and a sliding device (5); the main positioner (1) is fixed on the upper part of the overall frame (4); the fork ear positioner (2) is fixed on both sides of the overall frame (4); the equipment drilling template (3) is installed on both sides of the overall frame (4), and the sliding device (5) is installed on the lower side of the overall frame (4); the main positioning reference is the upper side structure of the large helicopter component, the main reduction platform or the engine platform is connected to the hole of the main positioner (1), and the surface is fitted; the auxiliary positioning is that the initial hole of the fork ear joint is connected to the hole of the fork ear positioner (2), and the surface is fitted, and the fork ear positioner (2) and the equipment drilling template (3) are driven by the sliding device (5) to work reciprocatingly. 2) Inspection before production: Use inspection pins with the diameter of the initial hole of the fork ear structure minus 0.8mm, the diameter of the initial hole minus 1.0mm, and the diameter of the initial hole minus 1.2mm to inspect the coaxiality between the initial hole of the fork ear structure and the hole of the fork ear locator (2). The inspection pins are used in descending order, and the assembly error accumulation deviation detection data is recorded for tool adjustment; 4) Preparation before production: The tool material is a carbide internally cooled tool with a front guide, which consists of a blade and a tool bar. The front guide diameter of the tool bar of each specification is the same. The rough and fine processing of the hole can be achieved by replacing the blade and tool bar. According to the pre-production inspection data, use the tool setting instrument to adjust the fine boring tool for the final hole. After adjusting the tool, use the equipment drilling template (3) of the high-precision rigid fixture to locate the portable boring drill, insert the portable boring drill indexing bayonet into the guide hole of the equipment drilling template (3), rotate the indexing bayonet counterclockwise to ensure that the indexing bayonet is locked with the equipment drilling template (3), and use the rotary dividing head function to adjust the portable boring drill to the best working posture; 5) High-precision hole making: The hole making path is from left to right and from top to bottom. When making one group of holes, it is necessary to insert locating pins to fix the three groups of holes on the same side and at least one group of holes on the opposite side. Four-level hole making is adopted, namely rough boring correction once, rough boring twice, and fine boring once. The speed range is 150rpm~200rpm, the feed speed range is 0.02~0.04mm / r, the rough boring cutting range is 0.2mm~0.8mm, and the fine boring cutting range is 0.15mm~0.25mm.

2. The high-precision hole making method for a multi-fork ear aircraft structure according to claim 1, characterized in that: The main positioner (1) is composed of a platform hole positioner, a platform surface positioner, an extension mechanism, and multiple groups of positioning bolts; the extension mechanism is firmly connected to the overall frame (4), the platform hole positioner and the platform surface positioner are firmly connected to the extension mechanism, the extension mechanism is an intermediate structure connecting the upper and lower parts, and the multiple groups of positioning bolts are used to connect the product with the platform hole positioner.

3. The high-precision hole making method for a multi-fork ear aircraft structure according to claim 2, characterized in that: The number of the positioning bolts corresponds to the number of platform holes on the product.

4. The high-precision hole making method for a multi-fork ear aircraft structure according to claim 1, characterized in that: The fork ear locator (2) is composed of a fork ear hole locator, a fork ear surface locator, an extension mechanism, and a series of specification inspection pins. The extension mechanism is firmly connected to the overall frame (4). The fork ear hole locator and the fork ear surface locator are firmly connected to the extension mechanism. The extension mechanism is an intermediate structure connecting the upper and lower parts. Series specification test pins are used to test connection products and fork lug locators.

5. The high-precision hole making method for a multi-fork ear aircraft structure according to claim 4, characterized in that: The specifications and quantity of the series of inspection pins are determined based on the diameter and quantity of the processed holes.

6. The high-precision hole making method for a multi-fork ear aircraft structure according to claim 4, characterized in that: The series specification inspection pin checks the coaxiality between the product and the equipment drilling template (3).

7. The high-precision hole making method for a multi-fork ear aircraft structure according to claim 1, characterized in that: The equipment drilling template (3) consists of a drilling template and a supporting structure. One side of the supporting structure is firmly connected to the overall frame (4), and the other side is connected to the drilling template. The supporting structure is an intermediate mechanism used for drilling holes in the equipment.

8. The high-precision hole making method for a multi-fork ear aircraft structure according to claim 1, characterized in that: The overall frame (4) is a steel welded structure, which can safely bear its own weight, the weight of other module structures and the weight of the product, and is firmly connected to the ground and to other module structures.

9. The high-precision hole making method for a multi-fork ear aircraft structure according to claim 1, characterized in that: The sliding device (5) is composed of a slide rail assembly, an upper / lower positioning support, and a limiter; the upper / lower positioning support is connected to the slide rail assembly and moves back and forth with the slide rail assembly; the limiter is connected to the overall frame (4) and opens and closes with the upper / lower positioning support to limit the position of the slide rail assembly.

10. The high-precision hole making method for a multi-fork ear aircraft structure according to claim 1, characterized in that: The number of the fork lug positioners (2) and the equipment drilling template (3) corresponds to the number of the fork lugs.

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