Aluminum alloy profile forming method for high-precision frame

Abstract

The present invention relates to the technical field of aluminum alloy hot extrusion forming, and in particular to a method for forming an aluminum alloy profile of a high-precision frame, comprising the following steps: a forming die is installed inside an extrusion barrel, and the forming die and the extrusion barrel are heated to a set temperature at the same time; an aluminum alloy rod is fed into the extrusion barrel, and an extrusion pin is extruded on the aluminum alloy rod in the extrusion barrel, and is extruded into a profile blank through the forming die; a traction machine clamps the end of the profile blank, and drives the profile blank to pass through a first nitrogen cooling chamber, a first shaping die, a second nitrogen cooling chamber, and a second shaping die in sequence; the profile blank that has been cooled and shaped is cut and artificially aged to obtain an aluminum alloy profile finished product, wherein the wall thickness of the aluminum alloy profile finished product is 1-2 mm, and the maximum width of the aluminum alloy profile is 20-45 mm. The method of the present invention has the characteristics of high forming precision, short forming production line length, and small footprint, and is particularly suitable for the forming of screen frame profiles.

Description

Technical Field

[0001] The invention relates to the technical field of aluminum alloy hot extrusion forming, and in particular to a method for forming an aluminum alloy profile of a high-precision frame. Background Art

[0002] At present, the production process of aluminum profiles is as follows: aluminum rods are fed to the extruder, and the extrusion ejector of the extruder squeezes the aluminum rods to form aluminum profiles through the forming die. The formed aluminum profiles are cold quenched to about 200°C and transferred to the storage bed for parking and cooling. When the aluminum profiles are cooled to about 50°C, the aluminum profiles are stretched and straightened by clamping the two ends of the aluminum profiles with a straightening machine. The elongation of the stretching is generally 2~3%. After that, the waste at both ends of the aluminum profiles is cut off and transferred to the aging furnace for artificial aging. During stretching and straightening, two clamping claws are required to clamp the two ends of the aluminum profile placed on the storage bed respectively, and then the two clamping claws move toward each other to stretch the aluminum profiles to achieve the straightening effect. Since the two clamping claws cannot accurately position the aluminum profile and are affected by the flatness of the stock bed, the aluminum profile is prone to deflection after being clamped by the two clamping claws; moreover, it is difficult to accurately control the elongation of the aluminum profile by the two clamping claws. If the elongation is small, the straightening effect cannot be achieved. If the elongation is large, the side opening of the aluminum profile will be deformed, affecting the forming accuracy of the aluminum profile.

[0003] A certain molding accuracy is required for the frame profile, especially for the frame of the teaching multimedia screen, which requires the frame and the screen to have a good assembly effect, and the two adjacent frames must be docked with high accuracy, and the entire screen device must have a good flatness after complete assembly. Moreover, the wall thickness of the screen frame profile is relatively small, and the stretching straightening method makes the side opening of the frame profile easily deformed. There are also roller straightening methods in the prior art, such as a channel-type extrusion straightening and cutting device for aluminum profiles disclosed in CN113600643A, which extrude the surface of the profile by multiple groups of horizontal and vertical extrusion rollers to achieve a straightening effect, but for screen frame profiles with smaller wall thickness, it is easy to cause deformation at the side opening, making it difficult for the side opening to achieve precise flatness. It can be seen that for the frame of the teaching multimedia screen with a tolerance number of more than a dozen, the existing aluminum profile process is difficult to obtain a frame profile product with a high pass rate. On the other hand, in the prior art, cold quenching and straightening are usually completed in two workstations respectively. The aluminum profile is straightened only after the cold quenching is completed. The molding production line is long and occupies a large area. For high-precision thin-walled profiles, deformation may occur during cold quenching and parking, and straightening is difficult. Summary of the invention

[0004] The purpose of the present invention is to provide a method for forming an aluminum alloy profile with a high-precision frame, which has the characteristics of high forming accuracy, short forming production line length and small footprint, and is particularly suitable for the forming of screen frame profiles.

[0005] To achieve this object, the present invention adopts the following technical solutions:

[0006] A method for forming an aluminum alloy profile with a high-precision frame comprises the following steps:

[0007] S1. The molding die is installed inside the extrusion barrel, and the molding die and the extrusion barrel are heated to a set temperature at the same time;

[0008] S2, the aluminum alloy rod is loaded into the extrusion barrel, the extrusion top is pressed against the aluminum alloy rod in the extrusion barrel, and the aluminum alloy rod is extruded into a profile blank through the forming die;

[0009] S3, the process downstream of the forming mold is provided with a cooling and shaping cylinder, the cooling and shaping cylinder cools and shapes the profile blank, the cooling and shaping cylinder includes a first nitrogen cooling cavity, a first shaping mold, a second nitrogen cooling cavity and a second shaping mold connected, and a traction machine clamps the end of the profile blank, driving the profile blank to pass through the first nitrogen cooling cavity, the first shaping mold, the second nitrogen cooling cavity and the second shaping mold in sequence;

[0010] S4. Cutting and artificially aging the profile blank after cooling and shaping to obtain a finished aluminum alloy profile. The wall thickness of the finished aluminum alloy profile is 1-2 mm, and the maximum width of the aluminum alloy profile is 20-45 mm.

[0011] Furthermore, in S3, the distance between the cooling and shaping cylinder and the forming mold is less than 1 m;

[0012] The temperature of the profile blank when entering the first shaping die is 300-400°C, and the temperature of the profile blank at the outlet of the cooling shaping cylinder is less than 50°C.

[0013] Further, the length of the first nitrogen cooling chamber of the cooling and shaping cylinder is 50-80 cm, the length of the first shaping mold is 2-3 cm, the length of the second shaping mold is 8-12 cm, and the second nitrogen cooling chamber is 100-150 cm;

[0014] The time for the profile blank to pass through the cooling and shaping cylinder is 8 to 15 seconds.

[0015] Furthermore, both the first shaping die and the second shaping die are provided with die holes, and the inner wall of the die hole is in contact with the outer wall of the profile blank;

[0016] The inner wall of the side opening groove of the profile blank is provided with a limiting strip, and during shaping, a clearance is left between the die hole and the limiting strip.

[0017] Furthermore, the second nitrogen cooling chamber is divided into a front cooling section and a rear cooling section by a partition plate with through holes, and the nitrogen discharged from the rear cooling section is used to cool the front section of the forming mold and the extrusion barrel; the nitrogen after cooling the front section of the forming mold and the extrusion barrel is used to heat the rear section of the extrusion barrel.

[0018] Furthermore, after the molding die is installed in the extrusion barrel, the molding die and the extrusion barrel are heated simultaneously by industrial frequency induction heating;

[0019] A gas cavity is provided inside the side wall of the extrusion barrel, and a perforated plate in the gas cavity separates the gas cavity into a front cooling cavity and a rear heating cavity; the forming die is attached to the inner wall of the extrusion barrel, and the nitrogen discharged from the rear cooling section enters the front cooling cavity;

[0020] The front end of the molding die is detachably connected with a die plate, and the die plate is fixed to a frame in front of the extruder.

[0021] Furthermore, a spiral tube is fixed to the inner wall of the first nitrogen cooling chamber and the interior of the second nitrogen cooling chamber respectively, the spiral tube is provided with an air injection hole, and one end of the spiral tube is connected to the liquid nitrogen tank;

[0022] The first nitrogen cooling cavity, the front cooling section of the second nitrogen cooling cavity and the rear cooling section of the second nitrogen cooling cavity respectively have exhaust holes; the exhaust hole of the second nitrogen cooling cavity is adjacent to the second shaping mold.

[0023] Furthermore, the traction machine includes a rope-retracting roller, a thin rope, a connecting rod and a clamp, the thin rope is wound around the rope-retracting roller, one end of the connecting rod is connected to the thin rope, and the other end is connected to the clamp, the clamp is used to clamp the end of the profile blank and carry the profile blank through the cooling and forming cylinder, and the length of the connecting rod is greater than the length of the cooling and forming cylinder.

[0024] Further, the material model of the aluminum alloy rod is 6030-T5, and in S1, the set temperature of the forming die and the extrusion cylinder is 480±5°C;

[0025] In S2, the feeding temperature of the aluminum alloy rod is 480±5°C, and during the extrusion process, the outlet temperature of the forming die is 525±5°C;

[0026] In S4, the artificial aging temperature is 200±5° C. and the time is 3.5 h.

[0027] Furthermore, the molding mold includes an upper mold and a lower mold, the calculation formula of the core length of the upper mold is L1=L2(1+K2t), and the calculation formula of the working belt length of the lower mold is L2= (1+a / t)tK1K2, wherein t is the nominal dimension of the profile wall thickness, K1 is the mold material strength coefficient, K2 is the ratio of the flow velocity difference at the mold hole position, and a is the thickness tolerance data.

[0028] The technical solution provided by the present invention may include the following beneficial effects:

[0029] The method of the present invention is used for forming aluminum alloy profiles of high-precision frames, especially for frames of teaching multimedia screens, and the wall thickness of the finished aluminum alloy profile is 1-2 mm. The forming accuracy of the aluminum alloy profile is improved by designing the length of the cooling and shaping cylinder and the working part of the forming die. Specifically, the cooling and shaping cylinder can simultaneously complete the cold quenching and straightening of the profile blank, improve the accuracy of the profile cross-sectional size, and the obtained product can avoid the phenomenon of deflection, tilting and uneven opening, greatly improving the qualified rate of the product.

[0030] In the present invention, the forming die is heated after being installed inside the extrusion barrel, and no additional heating work of the forming die is required, and the length of the waste material in the initial stage of extrusion molding is reduced. At the same time, the nitrogen in the cooling setting barrel is used to equalize the temperature of the forming die and the extrusion barrel, and the nitrogen is fully utilized to simplify the structure of the extrusion equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 is a schematic diagram of a profile production line according to an embodiment of the present invention;

[0032] Figure 2 It is a schematic diagram of the axial section of the cooling and shaping cylinder;

[0033] Figure 3 It is a schematic diagram of the cooperation between the extrusion cylinder, the forming die and the die plate;

[0034] Figure 4 is a cross-sectional schematic diagram of a forming die;

[0035] Figure 5 It is a cross-sectional schematic diagram of the frame of the teaching multimedia screen;

[0036] Figure 6 is a cross-sectional schematic diagram of a first shaping die;

[0037] Figure 7 It is a schematic diagram of the frame of the teaching multimedia screen being formed in cooperation with the first shaping mold or the second shaping mold;

[0038] Among them, the profile blank 01, the extrusion cylinder 1, the gas cavity 11, the front cooling cavity 12, the rear heating cavity 13, the forming mold 2, the upper mold 21, the mold core 211, the lower mold 22, and the working belt 221;

[0039] Cooling and shaping cylinder 3, first nitrogen cooling cavity 31, first shaping mold 32, mold hole 321, clearance gap 301, second nitrogen cooling cavity 33, second shaping mold 34, spiral tube 35, partition plate 36;

[0040] Extrusion ejector 4, mold plate 5, traction machine 6, frame 7, corner code mounting position 71, screen mounting position 72, light strip mounting position 73, light-transmitting plate mounting position 74, and limit strip 75. DETAILED DESCRIPTION

[0041] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0042] Combine the following Figures 1 to 7 , describing a method for forming an aluminum alloy profile of a high-precision frame according to an embodiment of the present invention.

[0043] A method for forming an aluminum alloy profile of a high-precision frame according to an embodiment of the present invention comprises the following steps:

[0044] S1, the molding die 2 is installed inside the extrusion cylinder 1, and the molding die 2 and the extrusion cylinder 1 are heated to a set temperature at the same time;

[0045] S2, the aluminum alloy rod is loaded into the extrusion barrel 1, and the extrusion ejector 4 extrude the aluminum alloy rod in the extrusion barrel 1, and is extruded through the forming die 2 to form a profile blank 01;

[0046] S3, the process downstream of the forming mold is provided with a cooling and shaping cylinder, the cooling and shaping cylinder cools and shapes the profile blank, the cooling and shaping cylinder 3 includes a first nitrogen cooling chamber 31, a first shaping mold 32, a second nitrogen cooling chamber 33 and a second shaping mold 34 connected, the tractor 6 clamps the end of the profile blank 01, and drives the profile blank 01 to pass through the first nitrogen cooling chamber 31, the first shaping mold 32, the second nitrogen cooling chamber 33 and the second shaping mold 34 in sequence;

[0047] S4. Cutting and artificially aging the profile blank 01 after cooling and shaping to obtain a finished aluminum alloy profile. The wall thickness of the finished aluminum alloy profile is 1-2 mm, and the maximum width of the aluminum alloy profile is 20-45 mm.

[0048] The method of the present invention is used for the aluminum alloy profile forming of high-precision frame, especially for the frame 7 of teaching multimedia screen, and the wall thickness of the finished aluminum alloy profile is 1-2mm. Specifically, the cooling and shaping cylinder 3 can complete the cold quenching and straightening of the profile blank 01 at the same time, and the entire outer surface of the profile blank 01 can be shaped by the first shaping die 32 and the second shaping die 34, and the accuracy of the profile cross-sectional size is improved while completing the straightening. The obtained product can avoid the phenomenon of deflection, tilting and uneven opening, and greatly improves the qualified rate of the product. At the same time, the profile blank 01 is cooled with nitrogen in the cooling chamber, which can greatly improve the cooling efficiency. Although there is a disclosure in the prior art that the profile is cooled with nitrogen, such as a liquid nitrogen cooling and quenching equipment for aluminum alloy profile extrusion production disclosed in CN218059100U. This equipment cannot solve the problems of low profile forming accuracy of the frame 7 and the difficulty of straightening caused by cold quenching and straightening being completed in two stations and the long length of the forming production line.

[0049] Further explanation, the profile blank 01 passes through the first nitrogen cooling chamber 31, the first shaping die 32, the second nitrogen cooling chamber 33 and the second shaping die 34 in sequence. The first shaping die 32 is used to shape the profile blank 01 once during the cold quenching process, especially to shape the side opening of the profile blank 01, so as to improve the matching accuracy between the side opening of the profile and the screen. The second shaping die 34 is not only used to shape the cross section of the profile blank 01 again, but also to straighten the profile blank 01 in coordination with the second shaping die 34 and the tractor 6. Moreover, after the first shaping die 32 shapes the profile blank 01 once, it can reduce the resistance of the profile blank 01 passing through the second shaping die 34, which is conducive to ensuring the surface quality of the profile blank 01. It should be noted that the shaping die holes of the forming die 2, the first shaping die 32 and the second shaping die 34 are located in the same straight line and face each other, and the die holes 321 of the three have a small roughness.

[0050] In addition, in S1 of the present invention, the molding die 2 is heated simultaneously after being installed inside the extrusion barrel 1, and there is no need to set up a separate heating station for the molding die 2. The temperature of the front end of the extrusion barrel 1 and the entire molding die 2 are consistent, which is beneficial to make the flow rate of the metal in the entire molding die 2 more uniform at the initial stage of extrusion, thereby reducing the length of waste in the initial stage of extrusion molding of an aluminum alloy rod.

[0051] In order to further shorten the molding production line and ensure molding accuracy, in S3, the distance between the cooling and shaping cylinder 3 and the molding mold 2 is less than 1m;

[0052] The temperature of the profile blank 01 when entering the first shaping die 32 is 300-400° C., and the temperature of the profile blank 01 at the outlet of the cooling shaping cylinder 3 is less than 50° C.

[0053] The distance between the cooling and shaping cylinder 3 and the forming mold 2 is reduced to less than 1m, so that the profile blank 01 can quickly enter the cooling and shaping cylinder 3 after being formed, and also provide space for the end of the tractor 6 to clamp the profile blank 01, and it is convenient to observe the forming state. By limiting the temperature of the profile blank 01 entering the first shaping mold, the profile blank 01 has a certain softness when entering the first shaping mold 32, ensuring the shaping effect of the first shaping mold 32 on the profile blank 01, reducing the influence of the first shaping mold 32 on the surface effect of the profile blank 01, and the cooling temperature can be achieved by introducing a small amount of liquid nitrogen into the first nitrogen cooling chamber 31. The temperature of the profile blank 01 at the outlet of the cooling and shaping cylinder 3 is less than 50°C, and the profile blank 01 that has completed cold quenching and straightening and shaping has a low temperature and a stable shape, and can immediately enter the cutting process, thereby improving efficiency.

[0054] Furthermore, the length of the first nitrogen cooling chamber 31 of the cooling and shaping cylinder 3 is 50-80 cm, the length of the first shaping mold 32 is 2-3 cm, the length of the second shaping mold 34 is 8-12 cm, and the second nitrogen cooling chamber 33 is 100-150 cm; the time for the profile blank 01 to pass through the cooling and shaping cylinder 3 is 8-15 s.

[0055] By setting the length of the cooling and shaping cylinder 3 and the time for the profile blank 01 to pass through the cooling and shaping cylinder 3, the shaping speed of the profile blank 01 is limited. When the length of the first nitrogen cooling chamber 31 is 50-80 cm, the profile blank 01 can be cooled at a relatively slow speed in the cooling chamber to allow the uniform precipitation of the Mg2Si phase, thereby ensuring the mechanical properties and corrosion resistance of the profile blank 01. In addition, the first shaping die 32 with a smaller degree has a small resistance to the movement of the profile blank 01, while the second shaping die 34 with a larger length is conducive to improving the straightening effect. Moreover, based on the shaping of the profile blank 01 by the first shaping die 32, the resistance of the second shaping die 34 to the movement of the profile blank 01 can be reduced.

[0056] In order to further improve the smoothness of the profile blank 01 passing through the first shaping die 32 and the second shaping die 34 and improve the shaping effect, the first shaping die 32 and the second shaping die 34 are both provided with a die hole 321, and the inner wall of the die hole 321 is in contact with the outer wall of the profile blank 01;

[0057] The inner wall of the side opening groove of the profile blank 01 is provided with a limit strip 75 , and during shaping, a clearance space 301 is left between the die hole 321 and the limit strip 75 .

[0058] Exemplarily, the cross section of the frame 7 of the teaching multimedia screen is as follows: Figure 5As shown, the frame 7 includes a corner code installation position 71, a screen installation position 72, a light strip installation position 73 and a light-transmitting plate installation position 74. The screen installation position 72, the light strip installation position 73 and the light-transmitting plate installation position 74 are the side openings of the profile. The three installation positions are each provided with a limiting strip 75 for limiting the side edge of the screen, light strip or light-transmitting plate so that it can be fixed in the installation position. Accordingly, the cross-section of the first shaping mold 32 and the second shaping mold 34 is as shown in FIG. Figure 6 As shown, the mold holes 321 of the two shaping molds 2 are used to shape the entire outer wall of the frame 7, greatly improving the molding accuracy of the frame 7. At the same time, in order to improve the smoothness of shaping and avoid damage to the profile surface, during shaping, a clearance gap 301 is left between the mold hole 321 and the limiting strip 75 (refer to Figure 7 ).

[0059] As an optional embodiment, the forming die 2 has a plurality of forming holes, and correspondingly, the first shaping die and the second shaping die also have a plurality of die holes, so that a plurality of profile blanks can be extruded simultaneously, thereby improving production efficiency.

[0060] In one embodiment of the present invention, the second nitrogen cooling chamber is divided into a front cooling section and a rear cooling section by a partition plate 36 with a through hole. The nitrogen discharged from the rear cooling section is used to cool the front section of the molding die 2 and the extrusion barrel 1; the nitrogen after cooling the front section of the molding die 2 and the extrusion barrel 1 is used to heat the rear section of the extrusion barrel 1.

[0061] It should be noted that during the extrusion molding process of aluminum profiles, the front section of the molding die 2 and the extrusion barrel 1 will heat up due to friction, while the temperature of the rear section of the extrusion barrel 1 will decrease as the heat is dissipated. If the front section of the molding die 2 and the extrusion barrel 1 continues to heat up, the extrusion temperature will be higher than the set value, and the metal flow rate will be accelerated, affecting the molding effect of the profile. In the prior art, the molding die 2 is cooled and the extrusion barrel 1 is heated, which makes it difficult to make the temperatures of the molding die 2 and the extrusion barrel 1 consistent, and the contact position between the molding die 2 and the extrusion barrel 1 cannot be accurately controlled in temperature.

[0062] In the present invention, the second nitrogen cooling chamber for cooling the shaping cylinder 3 needs to cool the profile blank 01 to below 50°C, so the temperature of the discharged nitrogen is relatively low, so the front section of the forming mold 2 and the extrusion cylinder 1 can be cooled, and the heated nitrogen contacts the rear section of the extrusion cylinder 1 to heat it up, so that the temperature of the forming mold 2 and the entire extrusion cylinder 1 tends to be close, and the nitrogen is fully recycled.

[0063] Specifically, after the molding die 2 is installed in the extrusion barrel 1, the molding die 2 and the extrusion barrel 1 are heated simultaneously by industrial frequency induction heating;

[0064] A gas cavity 11 is provided inside the side wall of the extrusion barrel 1, and a perforated plate in the gas cavity 11 separates the gas cavity 11 into a front cooling cavity 12 and a rear heating cavity 13; the molding die 2 is attached to the inner wall of the extrusion barrel, and the nitrogen discharged from the rear cooling section of the second nitrogen cooling cavity enters the front cooling cavity 12;

[0065] The front end of the molding die 2 is detachably connected to a die plate 5 , and the die plate 5 is fixed to a frame in front of the extruder.

[0066] Since the extrusion barrel 1 is made of metal and has good thermal conductivity, the nitrogen in the gas chamber 11 can quickly transfer heat to the inner wall of the extrusion barrel 1. Preferably, a guide plate or a guide groove is added inside the gas chamber 11 to improve the heat exchange effect. Exemplarily, an industrial frequency induction heating device is used to heat the extrusion barrel 1 and the molding die 2, or an industrial frequency induction heating device is fixed to the outer wall of the extrusion barrel 1.

[0067] As an optional embodiment, the inner wall of the extrusion barrel 1 has a limiting step, one end of the forming mold 2 is against the limiting step, and the other end of the forming mold 2 is flush with the end of the extrusion barrel 1, so that the extrusion barrel 1 wraps the entire forming mold 2. The end of the forming mold 2 has a limiting convex ring or a limiting convex block, and accordingly, the mold plate 5 is provided with a limiting groove to achieve the limitation of the forming mold 2. During the extrusion molding process, the mold plate 5 is used to maintain the position of the extrusion barrel 1 and the forming mold 2. When installing the forming mold 2, the forming mold 2 is first inserted into the extrusion barrel 1, and then the extrusion barrel 1 is moved toward the mold plate 5 until the limiting convex ring or the limiting convex block of the forming mold 2 is inserted into the mold plate 5. Preferably, a cooling spiral groove is provided on the outer wall of the forming mold 2, and the through hole spirally passing through the inner wall of the extrusion barrel 1 is connected to the gas cavity 11, and nitrogen can enter and exit the cooling spiral groove to improve the cooling effect on the forming mold 2.

[0068] As an optional embodiment, a spiral tube 35 is fixed to the inner wall of the first nitrogen cooling cavity and the interior of the second nitrogen cooling cavity, respectively. The spiral tube 35 is provided with an air jet hole, and one end of the spiral tube 35 is connected to the liquid nitrogen tank; the first nitrogen cooling cavity, the front cooling section of the second nitrogen cooling cavity, and the rear cooling section of the second nitrogen cooling cavity are respectively provided with an exhaust hole; the exhaust hole of the second nitrogen cooling cavity is adjacent to the second shaping mold 34. Nitrogen is sprayed into the first nitrogen cooling cavity and the second nitrogen cooling cavity through the air jet hole of the spiral tube 35, and the distribution of nitrogen in the two cooling cavities is easy to control, and the cooling shaping cylinder 3 has a simple structure.

[0069] In order to allow the profile blank 01 to smoothly enter and pass through the cooling and shaping cylinder, the traction machine 6 includes a retractable rope roller, a thin rope, a connecting rod and a clamp. The thin rope is wound around the retractable rope roller, one end of the connecting rod is connected to the thin rope, and the other end is connected to the clamp. The clamp is used to clamp the end of the profile blank 01 and carry the profile blank 01 through the cooling and shaping cylinder 3. The length of the connecting rod is greater than the length of the cooling and shaping cylinder. As an optional embodiment, the traction machine 6 is slidably arranged on one side of the molding production line, and the connecting rod is fixed to the traction machine 6. As the traction machine 6 slides, the profile blank 01 is pulled.

[0070] In one embodiment of the present invention, taking the aluminum alloy of model 6030-T5 as an example, in S1, the set temperature of the forming die 2 and the extrusion barrel 1 is 480±5°C; in S2, the feeding temperature of the aluminum alloy bar is 480±5°C, and during the extrusion process, the outlet temperature of the forming die 2 is 525±5°C; in S4, the temperature of artificial aging is 200±5°C, and the time is 3.5h. By strictly controlling the temperature of extrusion molding, the stability of product molding and the hardness and strength of the product are guaranteed. Specifically, the temperature of the outlet of the forming die 2 during the extrusion molding process is controlled by controlling the speed of nitrogen entering the gas chamber 11.

[0071] In order to further improve the molding accuracy, the molding die includes an upper die and a lower die. The calculation formula of the core length of the upper die is L1=L2(1+K2t), and the calculation formula of the working belt length of the lower die is L2= (1+a / t)tK1K2, where t is the nominal size of the profile wall thickness, K1 is the mold material strength coefficient, K2 is the ratio of the flow velocity difference of the mold hole position, and a is the thickness tolerance data. The value of K1 is between 1.5 and 2.0.

[0072] The die core 211 and the working belt 221 form a combined profile die hole 321, which is the working part of the forming die 2. The length of the two is set to ensure the size and surface quality of the extruded profile. It should be noted that in the prior art, when the working belt 221 of the aluminum profile extrusion forming die 2 is selected, it is only related to the nominal thickness in terms of the profile size. When the aluminum profile cross section is more complex and the precision requirement is high, the forming precision of the forming die 2 obtained by the existing forming die 2 design method is insufficient, and multiple modifications are required to barely meet the forming precision requirements. The aluminum alloy profile of the present invention is used for the screen frame 7, which not only has a side opening, but also has a plurality of limit strips 75 inside the side opening. In order to ensure high-precision matching between the frame 7 and the screen and the docking accuracy of the two connected frames 7, a large amount of thickness tolerance data is designed in the aluminum alloy profile. The length of the core 211 of the upper mold 21 and the length of the working band 221 of the lower mold 22 of the present invention are related, and the tolerance data is added to the calculation of the length of the core 211 and the working band 221. The length of the working part of the molding mold 2 is increased as a whole, which is beneficial to improving the molding accuracy and greatly reducing the number of adjustments and modifications to the molding mold.

[0073] Other structures and operations of the aluminum alloy profile forming method for a high-precision frame according to an embodiment of the present invention are known to ordinary technicians in the field and will not be described in detail here.

[0074] In the description of the present invention, it is necessary to understand that the terms "longitudinal", "transverse", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, features defined as "first" or "second" may explicitly or implicitly include one or more of the features, and are used to distinguish and describe features, without distinction of order or importance.

[0075] In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0076] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0077] In the description of this specification, the description with reference to the terms "embodiment", "example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0078] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A method for forming an aluminum alloy profile with a high-precision frame, characterized in that: The following steps are involved: S1. The molding die is installed inside the extrusion barrel, and the molding die and the extrusion barrel are heated to the set temperature at the same time; S2, the aluminum alloy rod is loaded into the extrusion barrel, the extrusion top is pressed against the aluminum alloy rod in the extrusion barrel, and the aluminum alloy rod is extruded into a profile blank through the forming die; S3, the process downstream of the forming mold is provided with a cooling and shaping cylinder, the cooling and shaping cylinder cools and shapes the profile blank, the cooling and shaping cylinder includes a first nitrogen cooling cavity, a first shaping mold, a second nitrogen cooling cavity and a second shaping mold connected, and a traction machine clamps the end of the profile blank, driving the profile blank to pass through the first nitrogen cooling cavity, the first shaping mold, the second nitrogen cooling cavity and the second shaping mold in sequence; S4, cutting and artificially aging the profile blank after cooling and shaping to obtain a finished aluminum alloy profile, wherein the wall thickness of the finished aluminum alloy profile is 1-2 mm, and the maximum width of the aluminum alloy profile is 20-45 mm; In S3, the distance between the cooling and shaping cylinder and the forming mold is less than 1 m; The temperature of the profile blank when entering the first shaping die is 300-400°C, and the temperature of the profile blank at the outlet of the cooling shaping cylinder is less than 50°C; The length of the first nitrogen cooling chamber of the cooling and setting cylinder is 50-80 cm, the length of the first setting mold is 2-3 cm, the length of the second setting mold is 8-12 cm, and the second nitrogen cooling chamber is 100-150 cm; The time for the profile blank to pass through the cooling and shaping cylinder is 8 to 15 seconds; The first shaping die and the second shaping die are both provided with a die hole, and the inner wall of the die hole is in contact with the outer wall of the profile blank; The inner wall of the side opening groove of the profile blank is provided with a limit strip, and during shaping, a clearance is left between the die hole and the limit strip; The second nitrogen cooling chamber is divided into a front cooling section and a rear cooling section by a partition plate with through holes. The nitrogen discharged from the rear cooling section is used to cool the front section of the forming mold and the extrusion barrel; the nitrogen after cooling the front section of the forming mold and the extrusion barrel is used to heat the rear section of the extrusion barrel; After the molding die is installed in the extrusion barrel, the molding die and the extrusion barrel are heated simultaneously by industrial frequency induction heating; A gas cavity is provided inside the side wall of the extrusion barrel, and a perforated plate in the gas cavity separates the gas cavity into a front cooling cavity and a rear heating cavity; the forming die is attached to the inner wall of the extrusion barrel, and the nitrogen discharged from the rear cooling section enters the front cooling cavity; The front end of the molding die is detachably connected with a die plate, and the die plate is fixed to a frame in front of the extruder.

2. The method for forming an aluminum alloy profile of a high-precision frame according to claim 1, characterized in that: A spiral tube is fixed to the inner wall of the first nitrogen cooling chamber and the interior of the second nitrogen cooling chamber respectively, the spiral tube is provided with an air injection hole, and one end of the spiral tube is connected to the liquid nitrogen tank; The first nitrogen cooling cavity, the front cooling section of the second nitrogen cooling cavity and the rear cooling section of the second nitrogen cooling cavity respectively have exhaust holes; the exhaust hole of the second nitrogen cooling cavity is adjacent to the second shaping mold.

3. The method for forming an aluminum alloy profile of a high-precision frame according to claim 1, characterized in that: The traction machine includes a rope-retracting roller, a thin rope, a connecting rod and a clamp. The thin rope is wound around the rope-retracting roller. One end of the connecting rod is connected to the thin rope, and the other end is connected to the clamp. The clamp is used to clamp the end of the profile blank and carry the profile blank through the cooling and forming cylinder. The length of the connecting rod is greater than the length of the cooling and forming cylinder.

4. The method for forming an aluminum alloy profile of a high-precision frame according to claim 1, characterized in that: The material model of the aluminum alloy rod is 6030-T5. In S1, the setting temperature of the forming die and the extrusion cylinder is 480±5°C; In S2, the feeding temperature of the aluminum alloy rod is 480±5°C, and during the extrusion process, the outlet temperature of the forming die is 525±5°C; In S4, the artificial aging temperature is 200±5° C. and the time is 3.5 h.

5. The method for forming an aluminum alloy profile of a high-precision frame according to claim 1, characterized in that: The molding die includes an upper die and a lower die. The calculation formula for the core length of the upper die is L1=L2(1+K2t), and the calculation formula for the working belt length of the lower die is L2= (1+a / t)⋅t⋅K1⋅K2, wherein t is the nominal dimension of the profile wall thickness, K1 is the mold material strength coefficient, K2 is the ratio of the flow velocity difference at the mold hole position, and a is the thickness tolerance data.

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