Multi-point reconstruction clamp for titanium alloy skin laser cutting

Abstract

The invention discloses a multi-point reconstruction clamp for titanium alloy skin laser cutting, the clamp is used for clamping a titanium alloy skin, a plurality of process pin lugs are arranged on the periphery of the titanium alloy skin, the clamp comprises a general laser cutting platform and a plurality of process supporting blocks, the main body of the general laser cutting platform is of a rectangular plane structure, the platform comprises a platform surface, pin holes and positioning holes. The upper surface of the process supporting block is manufactured according to the lug-shaped surface of the process pin of the titanium alloy skin, and the lower surface of the process supporting block is provided with a pin rod matched with the pin hole. The invention discloses a multi-point reconstruction clamp for titanium alloy skin laser cutting, which reduces the number of special laser cutting clamps in the titanium alloy skin laser cutting process, and solves the problems that the special laser cutting clamps are complicated in design process and high in manufacturing cost, the waste of working hours of turnover tools during production is serious, and the product quality is influenced by repositioning.

Description

Technical Field

[0001] The invention relates to a sheet metal parts laser cutting technology in the field of aircraft manufacturing, and specifically to a titanium alloy skin laser cutting fixture, which is particularly suitable for laser cutting of titanium alloy thin-wall skins with similar curvatures in a multi-point free combination support state. Background Art

[0002] The function of aircraft skin is to maintain the shape of the aircraft, make it have good aerodynamic characteristics, and reduce flight resistance. Therefore, the skin material is required to have high strength, good plasticity, and a smooth appearance after forming. Titanium alloy has the advantages of high specific strength, good high temperature performance and corrosion resistance, excellent dynamic load-bearing capacity, and certain shape memory performance. It is often used in the skin structure of various aircraft components and has received widespread attention in the aerospace industry. In order to meet the requirements of lightweight design, the proportion of titanium alloys used in key parts such as aircraft skins, wall panels and engine blades is increasing.

[0003] It is well known that most traditional aircraft skins are made of hard aluminum alloy materials, and their cutting process mostly uses manual cutting. Due to the low thermal conductivity, high hardness, and easy sticking of the titanium alloy skin after hot forming, traditional mechanical cutting is difficult, and the overall production efficiency and production accuracy are low. It is imperative to introduce more efficient cutting technology. Laser cutting has the advantages of high precision, narrow cutting seam, smooth surface, good cutting quality, fast cutting speed, non-contact cutting, a wide variety of cutting materials, and the ability to achieve plane, space surface, and complex graphics cutting. Laser cutting technology is used to cut titanium alloy skins. The laser does not contact the workpiece, does not generate cutting force, and has small deformation after processing. At present, the most advanced laser cutting technology is the five-axis laser processing technology. Its laser generation mode abandons the traditional carbon dioxide generation system and adopts more sophisticated optical fiber technology, making the quality of laser cutting products more stable and the accuracy higher.

[0004] As the core structural part of the aircraft's aerodynamic shape, titanium alloy skins are of various types and shapes. The traditional production plan requires the manufacture of hundreds of special laser cutting fixtures during batch production. The design process of tooling for different types of skin shapes is complicated and the manufacturing cost is high. During production, large-sized and heavy laser cutting special fixtures need to be hoisted, and a lot of man-hours are wasted on the turnover of tooling on the machine tool, which seriously restricts the production progress. During laser cutting, it is necessary to position according to the three positioning holes in different positions of the special fixture. When replacing the skin for cutting, the three points need to be manually re-positioned. There is a risk of displacement of the skin position, which affects the skin cutting accuracy and product quality. Therefore, there is an urgent need for a universal laser cutting fixture suitable for various types of titanium alloy thin-walled skins with large size, high hardness and high rebound characteristics after forming. Summary of the invention

[0005] In order to solve the problem of designing a universal laser cutting fixture suitable for precise cutting of various types and sizes of titanium alloy skins after forming; the present invention provides a multi-point reconstruction fixture for titanium alloy skin laser cutting, firstly by designing a universal laser cutting platform that meets the laser cutting height of a five-coordinate laser cutting machine, and then constructing a process pin ear with a matching curvature on the skin, and constructing a support block connecting the platform and the skin pin according to the ear shape. Different skin shapes only require the construction of different support blocks to overcome the problems of a large number of special fixtures in the batch production process, difficult turnover, changing special fixtures for repositioning, and low skin cutting accuracy.

[0006] The present invention provides a multi-point reconstruction fixture for titanium alloy skin laser cutting, which is used to clamp the titanium alloy skin. A plurality of process pin lugs are arranged around the titanium alloy skin. The fixture comprises: a universal laser cutting platform and a plurality of process support blocks;

[0007] The main body of the universal laser cutting platform is a rectangular plane structure, comprising: a platform table, a pin hole, and a positioning hole; the platform table matches the working area of ​​the laser cutting machine; a plurality of pin holes are arranged on the platform table, and the number of the pin holes is greater than the number of the process support blocks; positioning holes are arranged at the three top corners of the platform table;

[0008] The number of process support blocks is consistent with the number of process pin ears. The upper surface of the process support block is manufactured according to the process pin ear shape of the titanium alloy skin. The lower surface of the process support block is provided with a nail rod that matches the pin hole. The process pin ear and the process support block are connected by screws.

[0009] Optionally, a support base is provided under the platform table, the main body of the support base is a frame beam structure, and is integrally formed with the platform table. Six pressure plates are provided around the support base, and are connected to the laser cutting machine workbench by bolts;

[0010] The height of the support base is determined according to the cutting range of the laser cutting machine.

[0011] Optionally, a pin hole array is provided on the platform surface; each pin hole unit in the pin hole array includes two holes of different specifications;

[0012] The lower surface of the process support block is provided with two nail rods of different specifications which match with the pin hole units.

[0013] Optionally, the size of the process pin ear piece is larger than the size of the upper surface of the process support block;

[0014] Laser avoidance grooves are arranged around the upper surface of the process support block, and the shape of the laser avoidance grooves is determined according to the laser cutting parameters corresponding to the titanium alloy skin material.

[0015] Optionally, the process support block is a trapezoidal structure.

[0016] Optionally, a through hole is provided on the process support block, and the axis of the through hole is parallel to the trapezoidal bottom surface.

[0017] Optionally, corresponding numbers are set on the process support block and the platform positioning holes.

[0018] Optionally, a threaded hole is provided on the process support block, and the depth of the threaded hole is 20 mm.

[0019] The beneficial effects of this application are:

[0020] 1) The present invention provides a multi-point reconstruction fixture design for titanium alloy skin laser cutting and a method for using the same. By combining a universal laser cutting platform with a special support block, the present invention solves the problem that there are many types of skins and a large output, but the cost of cutting with a special laser cutting fixture is too high, and has important practical value.

[0021] 2) The present invention provides a design method for a multi-point reconstruction support block for laser cutting. By adopting a design method in which the upper surface of the support block is matched with the pin ear piece, and the lower surface is a pin structure matched with a universal laser cutting platform, the design accuracy of the laser cutting tooling is improved and a large amount of trial and error costs are reduced. The structural design, installation and operation of this series of new molds are simple and easy to promote and implement;

[0022] 3) When the laser cutting universal fixture is put into mass production of multi-specification skins, laser cutting can be performed by simply replacing the corresponding special support blocks of each skin, without the need to hoist large-sized and heavy laser cutting special fixtures, which greatly reduces the turnover time during production;

[0023] 4) During laser cutting, three positioning holes on the universal platform can be used for positioning, and manual forming positioning is avoided when replacing the support block, which greatly reduces the risk of skin position deviation and improves the skin cutting accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the titanium alloy skin surface;

[0025] Figure 2 This is a schematic diagram of the laser cutting fixture for titanium alloy skin;

[0026] Figure 3 This is a schematic diagram of the laser cutting platform structure;

[0027] Figure 4 This is a schematic diagram of the laser cutting support block structure;

[0028] Explanation of the reference numerals in the accompanying drawings: 1 titanium alloy skin, 2 process pin ear pieces, 3 universal laser cutting platform, 4 process support block, 5 platform table, 6 pin holes, 7 positioning holes, 8 upper surface of process support block, 9 lower surface of process support block, 10 screws, 11 support base, 12 pressure plate, 13 pin hole array, 14 nail rods of different specifications, 15 laser avoidance grooves, 16 through holes, 17 threaded holes. DETAILED DESCRIPTION

[0029] The present application is further described in detail below in conjunction with the accompanying drawings of the embodiments.

[0030] See attached Figure 1 The typical aircraft sheet metal parts provided in the embodiment are shown in the figure. The titanium alloy skin adopts TC4 alloy, with a thickness of about 2mm, a length of about 1.6m, a width of about 1.3m, and a maximum arch height of about 80mm. The titanium alloy skin presents a streamlined and smooth transition on both sides of the central axis. There can be hundreds of skins of this type and specifications on a single aircraft. The traditional production scheme requires the manufacture of hundreds of special laser cutting fixtures during batch production. The design process of tooling for different types of skin shapes is complicated and the manufacturing cost is high. During production, large-sized and heavy laser cutting special fixtures need to be hoisted, and a lot of working hours are wasted on the turnover tooling on the machine tool, which seriously restricts the production progress. During laser cutting, it is necessary to position according to the three positioning holes in different positions of the special fixture. When replacing the skin for cutting, it is necessary to manually re-position the three points. There is a risk of displacement of the skin position, which affects the skin cutting accuracy and product quality.

[0031] like Figure 2 to Figure 4 As shown, the present invention provides a multi-point reconstruction fixture for titanium alloy skin laser cutting, which is used to clamp a titanium alloy skin 1, and a plurality of process pin ears 2 are arranged around the titanium alloy skin; the fixture comprises: a universal laser cutting platform 3 and a plurality of process support blocks 4;

[0032] The main body of the universal laser cutting platform 3 is a rectangular plane structure, comprising: a platform table 5, a pin hole 6, and a positioning hole 7; the platform table 5 matches the working area of ​​the laser cutting machine; a plurality of pin holes 6 are provided on the platform table 5, and the number of the pin holes 6 is greater than the number of the process support blocks 4; positioning holes 7 are provided at the three vertex corners of the platform table 5;

[0033] The number of process support blocks 4 is consistent with the number of process pin ears 2. The upper surface 8 of the process support block is manufactured according to the shape of the process pin ear 2 of the titanium alloy skin. The lower surface 9 of the process support block is provided with a nail rod 14 that matches the pin hole. The process pin ear 2 and the process support block 4 are connected by screws 10.

[0034] Optionally, a support base 11 is provided under the platform table 5. The main body of the support base 11 is a frame beam structure, which is integrally formed with the platform table 5. Six pressure plates are provided around the support base 11, which is connected to the laser cutting machine workbench with bolts. The height of the support base 11 is determined according to the cutting range of the laser cutting machine.

[0035] Optionally, a pin hole array 13 is provided on the platform table 5; each pin hole unit in the pin hole array 13 includes two holes 6 of different specifications, and the lower surface of the process support block 4 is provided with two nail rods 14 of different specifications that match the pin hole array 13. The pin hole 6 matches the nail rod 14 to prevent positioning errors and reduce the risk of use caused by misuse of tooling.

[0036] Optionally, the size of the process pin ear piece 2 is larger than the size of the upper surface 8 of the process support block;

[0037] Laser avoidance grooves 15 are arranged around the upper surface 8 of the process support block. The shape of the laser avoidance grooves 15 is determined according to the laser cutting parameters corresponding to the titanium alloy skin 1 material. The laser cutting grooves can significantly reduce the damage of the laser to the support block and improve the service life of the tooling.

[0038] Optionally, the process support block 4 is a trapezoidal structure, which can be connected to the process pin ear piece 2 of the titanium alloy skin while connecting two error-proof nail rods of the skin, thereby reducing the use of tooling materials and saving costs.

[0039] Optionally, a through hole 16 is provided on the process support block 4, and the axis of the through hole 16 is parallel to the trapezoidal bottom surface. The support block 4 is too small compared to the platform 3. When batch production and application are performed, the number of support blocks 4 is too large, and they are easy to be mixed up or lost during storage. It is necessary to open a through hole 16 in all carcasses and use steel wire to bundle them together for storage, which can greatly reduce the tooling management cost.

[0040] Optionally, corresponding numbers are provided on the process support block 4 and the platform positioning hole 7, and the support block 4 is positioned by the numbers during cutting, so as to ensure that the position of the support block 4 is quickly determined during use, thereby reducing the use cost.

[0041] Optionally, a threaded hole 17 is provided on the process support block, and the threaded hole has a depth of 20 mm. Compared with ordinary pins, the threaded hole can improve the clamping performance.

Claims

1. A multi-point reconstruction fixture for titanium alloy skin laser cutting, characterized in that: Used to clamp the titanium alloy skin, and multiple process pin ears are arranged around the titanium alloy skin; the fixture includes: a universal laser cutting platform and multiple process support blocks; The main body of the universal laser cutting platform is a rectangular plane structure, comprising: a platform table, a pin hole, and a positioning hole; the platform table matches the working area of ​​the laser cutting machine; a plurality of pin holes are arranged on the platform table, and the number of the pin holes is greater than the number of the process support blocks; positioning holes are arranged at the three top corners of the platform table; The number of process support blocks is consistent with the number of process pin ears. The upper surface of the process support block is manufactured according to the process pin ear shape of the titanium alloy skin. The lower surface of the process support block is provided with a nail rod that matches the pin hole. The process pin ear and the process support block are connected by screws.

2. The multi-point reconstruction fixture for titanium alloy skin laser cutting according to claim 1 is characterized in that: A support base is provided under the platform surface. The main body of the support base is a frame beam structure, which is integrally formed with the platform surface. Six pressure plates are provided around the support base, which is connected to the laser cutting machine workbench with bolts. The height of the support base is determined according to the cutting range of the laser cutting machine.

3. The multi-point reconstruction fixture for titanium alloy skin laser cutting according to claim 1 is characterized in that: A pin hole array is arranged on the platform surface; each pin hole unit in the pin hole array includes two holes of different specifications; The lower surface of the process support block is provided with two nail rods of different specifications which match with the pin hole units.

4. The multi-point reconstruction fixture for titanium alloy skin laser cutting according to claim 1 is characterized in that: The size of the craft pin ear piece is larger than the size of the upper surface of the craft support block; Laser avoidance grooves are arranged around the upper surface of the process support block, and the shape of the laser avoidance grooves is determined according to the laser cutting parameters corresponding to the titanium alloy skin material.

5. The multi-point reconstruction fixture for titanium alloy skin laser cutting according to claim 1 is characterized in that: The process support block has a trapezoidal structure.

6. The multi-point reconstruction fixture for titanium alloy skin laser cutting according to claim 5 is characterized in that: A through hole is arranged on the process support block, and the axis of the through hole is parallel to the trapezoidal bottom surface.

7. The multi-point reconstruction fixture for titanium alloy skin laser cutting according to claim 1 is characterized in that: Corresponding numbers are set on the process support block and the platform positioning holes.

8. The multi-point reconstruction fixture for titanium alloy skin laser cutting according to claim 1 is characterized in that: The process support block is provided with a threaded hole, and the depth of the threaded hole is 20 mm.

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