An integrated tooling for flexible space curved surface products and its usage method

Abstract

The present invention provides an integrated tooling for flexible space curved surface products, which includes a convex mold (10), a concave mold (20), a positioning seat (30) and a parting component; both the convex mold (10) and the concave mold (20) are integrally arched structures, and the opposite surfaces of the convex mold (10) and the concave mold (20) adopt the same space torsion curved surface as the product; positioning seats (30) are respectively arranged at the front and rear ends of the convex mold (10) and the concave mold (20); square holes for installing the parting component are opened on the surfaces of the convex mold (10) and the concave mold (20) corresponding to the product positioning holes, and the parting component includes a parting insert (41) with a square cross-section and a protective steel sleeve (42) provided with external threads. Through the improvement of the mold structure, this integrated tooling ensures that accurate machining of the normal holes of each curved surface of the flexible curved surface product can also be carried out by using a three-axis machine tool, with high positioning accuracy and small error, effectively avoiding problems such as long scheduling and high costs in machining the normal hole rows of the curved surface by using a five-axis machine tool.

Description

Technical Field

[0001] The present invention relates to the technical field of tooling manufacturing, and particularly relates to an integrated tooling for flexible space curved surface products and its usage method. Background Art

[0002] With the development of new materials and new technologies, the types of composite products and their manufacturing processes are constantly innovating; large-area flexible composite materials are widely used in key parts of aircraft skins, special-shaped curved surface linings, and deep-sea exploration equipment, playing an important role in both military and civilian equipment.

[0003] Due to many factors considered in the design of various equipment, such as: when designing parts such as the skin and protective cover of a new type of aircraft, not only the influence of aerodynamic characteristics needs to be considered, but also the strength required by the fuselage parts to cope with vibration and external forces. To meet the demanding aerodynamic requirements, the above-mentioned parts (such as the skin and protective cover of a new type of aircraft) usually design their outer shapes as space-twisted curved surfaces; in order to ensure the assembly strength of composite products, the installation interfaces of the parts usually have a large number of settings and high precision requirements, and anti-vibration strength check tests need to be carried out after production; therefore, how to ensure the forming of flexible large-area space-twisted curved surface products (such as the skin and protective cover of a new type of aircraft) and the accurate machining of installation interfaces has become a key factor affecting product quality, which directly affects the assembly strength and compatibility of the parts with the overall equipment, and further affects the overall performance of the equipment.

[0004] Currently, when manufacturing flexible large-area space-twisted curved surface products, forming and drilling molds are usually used to ensure product accuracy; however, the manufacturing of forming and drilling molds for large-area curved surface products faces difficulties in accurately machining the normal holes of the curved surface using a three-axis machine tool (the flexible large-area space-twisted curved surface has a large volume and the hole positions are evenly distributed on the curved surface, and the three-axis machine tool cannot accurately find the normal lines on different curvature surfaces, resulting in high processing difficulty), and using a large five-axis machine tool for processing faces problems such as long scheduling (few five-axis machine tools) and high costs, which in turn affects the R & D and manufacturing progress of flexible large-area space-twisted curved surface products. Summary of the Invention

[0005] Aiming at the problems existing in the above prior art, the purpose of the present invention is to provide an integrated tooling for flexible space curved surface products. Through the improvement of the mold structure, this integrated tooling ensures that a three-axis machine tool can also accurately machine the normal holes of each curved surface of the flexible large-area space-twisted curved surface product, with high positioning accuracy and small error, effectively avoiding the problems of long scheduling and high costs in machining the normal holes of the curved surface using a five-axis machine tool, and greatly saving the manufacturing, verification time, and production cost of the flexible large-area space-twisted curved surface product.

[0006] Another purpose of the present invention is to provide a usage method for the above integrated tooling.

[0007] The object of the present invention is achieved by the following technical solutions:

[0008] An integrated tooling for flexible space curved surface products, characterized in that: it includes a male mold, a female mold, a positioning seat and a parting component; the female mold is located outside the male mold, and both the male mold and the female mold are of an arched structure as a whole, and the opposite surfaces of the male mold and the female mold (i.e., the surfaces of the male mold and the female mold that directly contact the product) adopt the same space-twisted curved surface as the product (i.e., the flexible space curved surface product); positioning seats are respectively arranged at the front and rear ends of the male mold and the female mold, and the positioning seats of the male mold and the female mold are respectively provided with pin holes and screw holes for installing positioning pins and fastening screws; square holes for installing the parting component are opened on the surfaces of the male mold and the female mold corresponding to the product positioning holes, and the parting component includes a parting insert with a square cross-section and a protective steel sleeve provided with external threads. The parting insert is in interference fit with the square hole, and a stepped hole is arranged in the middle of the parting insert. The stepped hole has a diameter decreasing from the outside to the inside. The protective steel sleeve is threadedly connected to the lower end (i.e., the small-diameter section) of the stepped hole, and the axis of the stepped hole is collinear with the curved surface normal of the corresponding male mold or female mold.

[0009] For further optimization, both the male mold and the female mold are integrally manufactured by forging small-volume raw materials into large-volume aluminum blocks and obtaining them through processing methods such as rough turning, finish turning and smooth surface material reduction manufacturing.

[0010] For further optimization, an arched reinforcing rib is arranged on the side of the male mold away from the female mold, and the lower ends of both sides of the side of the male mold away from the female mold are connected by multiple parallel support beams.

[0011] For further optimization, the lower end of the male mold is respectively connected to the two-side adapter plates by bolts.

[0012] For further optimization, the parting insert adopts a assembled structure.

[0013] For further optimization, an adapter is installed in the stepped hole of the male mold through a gasket and a nut. The cross-section of the adapter is a "T" shape structure, and its large-diameter section is stuck in the large-diameter section of the stepped hole. The small-diameter section of the adapter penetrates through the inner ring of the protective steel sleeve and is successively connected to the gasket and the nut. The gasket and the nut are arranged on the end surface of the male mold away from the female mold; a threaded hole is opened in the middle of the end surface of the large-diameter section of the adapter.

[0014] A method for using an integrated tooling for flexible space curved surface products, characterized in that: it includes a product manufacturing and forming method and a vibration test method;

[0015] The manufacturing and forming method is specifically as follows: First, disassemble the positioning pins and mounting screws, and remove the female die from the male die; then remove the adapter on the male die, lay the flexible material on the surface of the male die according to the process requirements of the flexible product, and perform extrusion and edge sealing to complete the preliminary forming of the flexible space curved surface product; after that, reinstall the female die on the male die with the flexible material laid, and install the positioning pins to pre-position between the female die and the male die; then, achieve the complete positioning between the male die and the female die and the complete forming of the product through the installation of fastening screws; finally, use a drilling tool to drill holes along the inner hole of the protective steel sleeve on the curved surface of the female die, and keep the male die and the female die fastened during the whole process to realize the opening of the positioning holes of the flexible space curved surface product; after all the positioning holes are processed, remove the female die and the formed product again;

[0016] The vibration test method is specifically as follows: First, disassemble the positioning pins and mounting screws, and remove the female die from the male die; then, check the installation of the adapters on the male die to ensure that each adapter is firmly installed, and check the connection between the male die and the adapter plate to ensure that the male die and the adapter plate are firmly connected; after that, install the adapter plate with the male die on the vibration test bench; finally, realize the firm connection between the flexible space curved surface product and the surface of the male die through bolts and threaded holes, and turn on the vibration test bench to conduct the vibration test.

[0017] The present invention has the following technical effects:

[0018] Through the cooperative design of the split insert, stepped holes and protective steel sleeve in this application's integrated tooling, the problem of being unable to accurately machine the normal holes of complex space torsion curved surfaces using a three-axis machine tool is effectively solved, thereby avoiding the use of a five-axis machine tool to machine the normal holes of complex space torsion curved surfaces, saving scheduling time, reducing production costs, and achieving cost reduction and efficiency increase; through the design of the square split insert, firstly, it can avoid the formation of torsional torque during the drilling or bolt fixing process, causing the split insert to rotate and shift, and secondly, by machining the normal holes on the split insert, the machining accuracy is guaranteed and the machining process is simplified (for example, complex or large split inserts can be processed in a modular manner, that is, the split insert is disassembled into three or four petals for processing); through the design of the protective steel sleeve, firstly, it forms a guiding effect on the drill bit during the drilling process to avoid the drill bit from shifting, secondly, it prevents the drill bit from damaging the split insert, and thirdly, it can effectively tightly position the adapter; through the positioning pins and fastening screws, not only the positioning and fastening between the male die and the female die are realized, but also the pressing forming of the product is assisted by the fastening force of the fastening screws and the self-weight of the female die.

[0019] The integrated tooling of this application realizes the integration of the forming manufacturing of flexible space curved surface products and the vibration tooling, can be used for the opening of multi-curved surface positioning holes of products, the pressing forming of products, and the high-intensity vibration test of products, realizes the mutual use of manufacturing molds and vibration tooling, greatly reduces the mold opening cost and processing cycle, saves energy and materials, and avoids waste of resources. Brief Description of the Drawings

[0020] Figure 1 It is a schematic diagram of the overall structure of the integrated tooling in the embodiment of the present invention.

[0021] Figure 2 It is a structural sectional view at the parting component of the integrated tooling in the embodiment of the present invention.

[0022] Figure 3 It is a schematic diagram of the three - coordinate detection of the female die in the embodiment of the present invention.

[0023] Figure 4 It is a schematic diagram of the three - coordinate point selection of the male die in the embodiment of the present invention; wherein, Figure 4 (a) is the point selection for the first group of molds, Figure 4 (b) is the point selection for the second group of molds, Figure 4 (c) is the point selection for the third group of molds, Figure 4 (d) is the point selection for the fourth group of molds.

[0024] Among them, 10, male die; 11, reinforcing rib; 12, support beam; 13, adapter plate; 20, female die; 30, positioning seat; 41, parting insert; 42, protective steel sleeve; 43, adapter; 431, threaded hole; 432, gasket; 433, nut. Detailed Description of the Embodiment

[0025] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0026] Embodiment 1:

[0027] As Figures 1 - 2 shown: Taking the preparation of a spatially twisted curved surface with a maximum outer dimension of 1309×710×505mm and a thickness of 10mm, and the positioning hole size of 7mm as an example:

[0028] An integrated tooling for a flexible spatial curved surface product, characterized in that it includes a male die 10, a female die 20, a positioning seat 30 and a parting component; the female die 20 is located outside the male die 10 (as Figure 1 shown: that is, the female die 20 is located above the male die 10), both the male die 10 and the female die 20 are of an arch structure as a whole, and the opposite surfaces of the male die 10 and the female die 20 (i.e., the surfaces of the male die 10 and the female die 20 that directly contact the product) adopt the same spatially twisted curved surface as the product (i.e., the flexible spatial curved surface product) (i.e., Figure 1The upper side of the punch 10 and the lower side of the die 20 adopt the same spatial torsion curved surface as the product); positioning seats 30 are respectively arranged at the front and rear ends of the punch 10 and the die 20 (as Figure 1 shown), and the positioning seats 30 of the punch 10 and the positioning seats 30 of the die 20 are respectively provided with pin holes and screw holes for installing positioning pins and fastening screws; both the punch 10 and the die 20 are integrally manufactured, and large-volume aluminum blocks are formed by forging small-volume raw materials, and are obtained by machining methods such as rough turning, finish turning and smooth surface subtractive manufacturing; the overall manufacturing material of the punch 10 and the die 20 can adopt 7075 aluminum alloy; during the mold manufacturing process, the surface roughness of the contact surfaces of the punch 10, the die 20 and the product is less than 3.2.

[0029] An arched reinforcing rib 11 is arranged on the side of the punch 10 away from the die 20 (as Figure 1 shown, and in this embodiment, the number of the reinforcing ribs 11 is 2, and the width of each reinforcing rib 11 is 40 mm), and the lower ends of both sides of the side of the punch 10 away from the die 20 are connected by a plurality of parallel support beams 12 (as Figure 1 shown, and in this embodiment, the number of the support beams 11 is 4); the lower end of the punch 10 is respectively connected to the two side adapter plates 13 by bolts, and the adapter plates 13 are provided with hole positions for connecting to the vibration test bench.

[0030] Square holes for installing the parting components are opened on the surfaces of the punch 10 and the die 20 and corresponding to the positions of the product positioning holes (that is, the positions where the product needs to be provided with positioning holes). The parting components include a parting insert 41 with a square cross-section and a protective steel sleeve 42 provided with external threads. The parting insert 41 is in interference fit with the square hole 42, and a stepped hole is arranged in the middle of the parting insert 41, and the stepped height is 3 mm. The side length of the parting insert 41 is 35 mm. The stepped hole decreases in diameter from the outside to the inside (for the punch 10: the large-diameter section of the stepped hole is at the end close to the product, and the small-diameter section is at the end away from the product; for the die 20: the small-diameter section of the stepped hole is at the end close to the product, and the large-diameter section is at the end away from the product). The diameter of the large-diameter section of the stepped hole is 15 mm, and the diameter of the small-diameter section is 10 mm; the protective steel sleeve 42 is threadedly connected to the lower end (that is, the small-diameter section) of the stepped hole. The protective steel sleeve 42 is made of high manganese steel, with an outer diameter of 10 mm and an inner diameter of 7 mm. The axis of the stepped hole is collinear with the curved surface normal of the corresponding punch 10 or die 20.

[0031] A transfer piece 43 is installed in the stepped hole of the punch 10 through a gasket 432 and a nut 433 (as Figure 2As shown in the figure, the cross-section of the adapter 43 is a "T" shape, and its large-diameter section is stuck in the large-diameter section of the stepped hole. The small-diameter section of the adapter penetrates through the inner ring of the protective steel sleeve 42 and is sequentially connected to the gasket 432 and the nut 433. The gasket 432 and the nut 433 are arranged on the end face of the punch 10 away from the die 20. A threaded hole 431 is opened in the middle of the end face of the large-diameter section of the adapter 43.

[0032] Embodiment 2:

[0033] As a further optimization of the solution of the present application, on the basis of the solution of Embodiment 1, the split insert 41 adopts an assembled structure, such as being composed of two, three, four or even five pieces spliced together, so as to completely fill the square hole; multiple split inserts 41 are bonded and connected into the square hole by a special metal glue (a common special metal glue in the field can be used).

[0034] At the same time, the structures of the square hole and the split insert 41 can also be set to be oval, pentagonal, hexagonal, etc. according to specific situations.

[0035] Embodiment 3:

[0036] A method for using the above-mentioned integrated tooling for flexible space curved surface products, which is characterized in that: it includes a product manufacturing and forming method and a vibration test method;

[0037] The manufacturing and forming method is specifically as follows: First, remove the positioning pin and the mounting screw, and remove the die 20 from the punch 10; then remove the adapter 43 on the punch 10, lay the flexible material on the surface of the punch 10 according to the process requirements of the flexible product, and perform extrusion and edge sealing to complete the preliminary forming of the flexible space curved surface product; after that, reinstall the die 20 on the punch 10 covered with the flexible material, and install the positioning pin to pre-position between the die 20 and the punch 10; then, through the installation of the fastening screw, complete the full positioning between the punch 10 and the die 20 and the full forming of the product; finally, use a drilling tool to drill holes along the inner hole of the protective steel sleeve 42 on the curved surface of the die 20, and keep the punch 10 and the die 20 fastened during the whole process to open the positioning holes of the flexible space curved surface product; after all the positioning holes are processed, remove the die 20 and the formed product again;

[0038] The vibration test method is specifically as follows: First, remove the positioning pins and mounting screws, and take the female mold 20 off the male mold 10; then, check the installation of the adapter 43 on the male mold 10 to ensure that each adapter 43 is firmly installed, and check the connection between the male mold 10 and the adapter plate 13 to ensure that the male mold 10 and the adapter plate 13 are firmly connected; after that, install the adapter plate 13 with the male mold 10 on the vibration test bench; finally, achieve the firm connection between the flexible space curved surface product and the surface of the male mold 10 through bolts and threaded holes 431, turn on the vibration test bench, and conduct the vibration test.

[0039] The three-coordinate detection method is used to randomly detect the curved surface hole positions of the mold. The three-coordinate detection of the female mold 20 is as Figure 3 shown, and the selected points of the male mold 10 are as Figure 4 shown. Some of the detection results are shown in Table 1 below:

[0040] Table 1: Three-coordinate detection results:

[0041] Hole position X - direction error Y - direction error Z - direction error Position tolerance 1 0.041 0.027 -0.006 ±0.2 2 -0.025 -0.242 0.014 ±0.2 3 -0.004 0.048 -0.021 ±0.2 4 -0.038 0.069 -0.002 ±0.2 5 -0.012 0.017 0.000 ±0.2 6 -0.025 0.023 0.090 ±0.2 7 -0.021 0.031 0.043 ±0.2 8 -0.029 0.039 0.031 ±0.2 9 0.065 0.083 -0.001 ±0.2 10 -0.039 0.062 0.011 ±0.2 11 -0.072 0.062 0.005 ±0.2 12 -0.074 0.072 0.013 ±0.2 13 -0.046 0.085 -0.002 ±0.2 14 -0.035 -0.077 0.045 ±0.2 … … … … … 77 -0.005 -0.141 -0.099 ±0.2 78 -0.008 -0.105 -0.140 ±0.2 79 -0.012 -0.040 -0.035 ±0.2

[0042] The test results show that: the position degree of the center point of the curved surface of each hole of the mold of the present application is within the range of ±0.2, that is, the position degree of the center point of the machined positioning hole curved surface is within the range of ±0.2, meeting the product interface precision requirements.

[0043] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An integrated tooling for flexible space curved surface products, characterized in that: It includes a punch, a die, a positioning seat and a parting component; the die is located outside the punch. The punch and the die are integrally of an arched structure, and the opposite surfaces of the punch and the die adopt the same spatial torsion curved surface as the product. Positioning seats are respectively arranged at the front and rear ends of the punch and the die, and the positioning seats of the punch and the die are respectively provided with pin holes and screw holes for installing positioning pins and fastening screws. Square holes for installing the parting component are opened on the surfaces of the punch and the die corresponding to the product positioning holes. The parting component includes a parting insert with a square cross-section and a protective steel sleeve with external threads. The parting insert is in interference fit with the square hole, and a stepped hole is arranged in the middle of the parting insert. For the punch: the stepped hole has a large-diameter section at the end close to the product and a small-diameter section at the end far from the product. For the die: the stepped hole has a small-diameter section at the end close to the product and a large-diameter section at the end far from the product. The protective steel sleeve is threadedly connected to the lower end of the stepped hole, and the axis of the stepped hole is collinear with the curved surface normal of the corresponding punch or die.

2. The integrated tooling for a flexible space curved surface product according to claim 1, characterized in that: An arched reinforcing rib is arranged on the side of the punch away from the die, and the lower ends of both sides of the side of the punch away from the die are connected by a plurality of parallel support beams.

3. The integrated tooling for a flexible space curved surface product according to claim 1 or 2, characterized in that: The lower end of the punch is respectively connected to the two side transfer plates by bolts.

4. The integrated tooling for a flexible space curved surface product according to claim 3, wherein: A transfer piece is installed in the stepped hole of the punch through a gasket and a nut. The cross-section of the transfer piece is of a "T" - shaped structure, and its large-diameter section is stuck in the large-diameter section of the stepped hole. The small-diameter section of the transfer piece penetrates through the inner ring of the protective steel sleeve and is sequentially connected to the gasket and the nut. The gasket and the nut are arranged on the end face of the punch away from the die. A threaded hole is opened in the middle of the end face of the large-diameter section of the transfer piece.

5. The usage method of an integrated tooling for a flexible space curved surface product according to claim 4, characterized in that: It includes a product manufacturing and forming method and a vibration test method. The manufacturing and forming method is specifically as follows: First, remove the positioning pins and installation screws, and take the die off the punch; then remove the transfer piece on the punch, lay the flexible material on the surface of the punch according to the process requirements of the flexible product, and perform extrusion and edge sealing to complete the preliminary forming of the flexible space curved surface product; after that, reinstall the die on the punch paved with the flexible material, and install the positioning pins to pre-position between the die and the punch; then, through the installation of the fastening screws, complete the full positioning between the punch and the die and the full forming of the product; finally, use a drilling tool to drill holes along the inner hole of the protective steel sleeve on the curved surface of the die, and keep the punch and the die fastened during the whole process to open the positioning holes of the flexible space curved surface product; after all the positioning holes are processed, take the die off again and take off the formed product. The vibration test method is specifically as follows: First, remove the positioning pins and installation screws, and take the die off the punch; then, check the installation of the transfer pieces on the punch to ensure that each transfer piece is firmly installed, and check the connection between the punch and the transfer plates to ensure that the punch and the transfer plates are firmly connected; after that, install the transfer plate with the punch on the vibration test bench; finally, through bolts and threaded holes, firmly connect the flexible space curved surface product to the surface of the punch, and turn on the vibration test bench to conduct the vibration test.

Images