Electromagnetic impact heterogeneous metal plate composite stamping integrated forming device and method

Abstract

The present invention discloses an electromagnetic impact heterogeneous metal plate composite stamping integrated forming device and method, the device comprises: a bottom die, the upper end of which is provided with a forming surface, and the forming surface is provided with an inward concave groove; a pressing electrode, which is movable and movable above the bottom die, is used to press the edge of the upper metal plate and electrically heat the upper metal plate; an upper die, which is movable and movable above the bottom die, and the bottom is provided with a pressing surface adapted to the forming surface; an electromagnetic pulse coil, which is installed on the upper die, is used to apply a high-speed electromagnetic impact load to the upper metal plate and the lower metal plate, so that the upper metal plate and the lower metal plate are interface-compounded under the coupling of high temperature and high-speed electromagnetic impact, and at the same time bulge toward the groove together, and the composite metal plate is fitted with the groove wall of the groove. The present invention realizes the heating of metal parts, the composite of heterogeneous materials and multiple stamping, shortens the process flow, improves production efficiency, has a short process flow, low energy consumption, good composite interface strength, and high forming accuracy.

Description

Technical Field

[0001] The present invention relates to the technical field of metal sheet stamping, and in particular to an electromagnetic impact heterogeneous metal sheet composite stamping integrated forming device and method. Background Art

[0002] With the transformation and upgrading of traditional manufacturing industry and the development of strategic emerging industries, more and more stringent requirements are put forward for the performance of engineering materials. It is difficult for traditional single metal or alloy materials to meet the demand. Therefore, the application of new metal composite materials to meet some high-end manufacturing and special industrial uses has become the mainstream development direction of modern processing manufacturing industry.

[0003] The traditional manufacturing of metal layered composite components is divided into two steps: first, the existing composite preparation process is used to realize the composite of heterogeneous layered plates; then, after the layered composite plate is prepared, it is used as a raw material for subsequent remanufacturing, such as stamping, spinning, forging and other subsequent forming processes, to make it into specific functional parts with multiple sizes, multiple features and complex surfaces. The forming and manufacturing of metal layered composite plates is much more complicated than the forming of single metal sheets, and faces many process problems. The interface strength and forming quality cannot be guaranteed, and there are many process flows, long forming cycles, and low production efficiency. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides an electromagnetic impact heterogeneous metal plate composite stamping integrated forming device and method.

[0005] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0006] An electromagnetic impact heterogeneous metal plate composite stamping integrated forming device comprises: a bottom die, the upper end of which is provided with a forming surface, and the forming surface is provided with an inwardly concave groove; a pressing electrode, which is lifted and moved above the bottom die, and is used to press the edge of an upper metal plate and electrically heat the upper metal plate; an upper die, which is lifted and moved above the bottom die, and the bottom is provided with a pressing surface adapted to the forming surface, and the pressing surface is used to cooperate with the forming surface to stamp and form the upper metal plate and the lower metal plate; an electromagnetic pulse coil, which is installed on the upper die, and is used to apply a high-speed electromagnetic impact load to the upper metal plate and the lower metal plate, so that the upper metal plate and the lower metal plate bulge toward the groove, and the lower metal plate fits with the groove wall of the groove.

[0007] Furthermore, it also includes a demolding ejector pin, which is elastically and movably installed on the bottom mold, and the demolding ejector pin has an ejection state protruding from the molding surface and a molding state flush with the molding surface; the demolding ejector pin in the molding state is against the bottom mold so that the force from top to bottom can be transmitted to the bottom mold, and the demolding ejector pin in the molding state is subjected to an elastic force moving toward the ejection state.

[0008] Furthermore, the demolding ejector column includes a bottom column and a protruding column connected to the upper end of the bottom column, the cross-sectional contour of the bottom column is larger than that of the protruding column; the molding surface is provided with a through hole extending downward, the protruding column is adapted to the through hole and movably penetrated through the through hole; the bottom of the through hole is connected to a bottom hole with a contour larger than the through hole, and a shoulder surface is formed at the upper end of the bottom hole and the lower end of the through hole; the bottom column is adapted to the contour of the bottom hole; the upper end surface of the bottom column in the ejected state is in contact with the shoulder surface; and a compression spring is installed at the bottom of the bottom column.

[0009] Furthermore, a reinforcing rib is provided between the shoulder surface and the peripheral wall of the bottom hole; the bottom column is provided with an avoidance strip for the reinforcing rib to be embedded in, and the thickness of the reinforcing rib is adapted to the width of the avoidance strip; in the ejection state and the forming state, the reinforcing rib is at least partially embedded in the avoidance strip.

[0010] Furthermore, the bottom mold includes a base and a molding part detachably connected to the top of the base, the molding surface, groove, through hole and bottom hole are all formed on the molding part, the bottom of the base is provided with a first annular groove for embedding a compression spring, the inner and outer sides of the upper end of the first annular groove are formed with abutment surfaces, the bottom of the bottom column is provided with a second annular groove for embedding a compression spring, the inner and outer sides of the lower end of the second annular groove are formed with force unloading surfaces for contacting the abutment surface.

[0011] Furthermore, the avoidance strip opening is communicated with the second annular groove so that air can flow on the upper and lower sides of the bottom column.

[0012] Furthermore, a pressure seat is provided on the outer periphery of the bottom mold, and a fixed electrode is provided on the upper end of the pressure seat. The fixed electrode is used to contact the bottom edge of the lower metal plate and electrically heat the lower metal plate.

[0013] The present invention also provides an electromagnetic impact composite stamping integrated forming method for heterogeneous metal plates, comprising the following steps: S1, placing an upper metal plate and a lower metal plate on the upper end of a bottom mold; S2, after a pressing electrode presses the upper metal plate and the lower metal plate, turning on a heating power supply to supply power to the pressing electrode so that the upper metal plate and the lower metal plate are electrically heated; S3, the upper mold moves downward to press the upper metal plate and the lower metal plate tightly against a forming surface; S4, energizing an electromagnetic pulse coil, the electromagnetic pulse coil generates a huge pulse electromagnetic force, impacting the upper metal plate and the lower metal plate, so that the upper metal plate and the lower metal plate bulge toward the groove, and the lower metal plate fits with the groove wall of the groove; S5, lifting the pressing electrode to release the pressing of the upper metal plate and the lower metal plate, and taking out the upper metal plate and the lower metal plate.

[0014] Further, in step S2, the upper metal plate and the lower metal plate need to be powered on and heated to a preset temperature and kept warm for a preset time.

[0015] Furthermore, the heating process of the upper metal plate and the lower metal plate is controlled according to the following formula:

[0016] ;

[0017] is the proportionality coefficient, for The integration coefficient at time, is the differential coefficient, is the current required temperature; is a recurrent neural network model, for Heater power parameters at the moment, for The influencing parameters of the moment, for The temperature of the moment, for The accumulated heating time at all times, for The output signal of the PID regulator at that moment.

[0018] The present invention has the following beneficial effects:

[0019] The edge of the upper metal plate is pressed by the edge pressing electrode and the upper metal plate is electrically heated, so that the metal plate is electrically heated while the edge of the metal plate is pressed, so that the metal has stronger fluidity and plasticity during stamping, and the defects such as wrinkling, tearing and micro cracks caused by stamping are smaller, and the workpiece has smaller springback after forming, and the forming accuracy is higher, so that the interface strength and forming quality of the workpiece are guaranteed. After heating, the pressing surface of the upper die is pressed down so that the pressing surface cooperates with the forming surface to stamp the upper and lower metal plates. After the metal plate basic structure is stamped and formed, the electromagnetic pulse coil is energized to heat the upper High-speed electromagnetic impact force is applied to the metal plate and the lower metal plate, so that the upper metal plate and the lower metal plate achieve interface bonding under the coupling action of high temperature and high-speed transient electromagnetic impact force, and at the same time, the protrusion toward the groove fits with the groove wall of the groove to achieve the bonding of the two layers of metal and the stamping forming of local small characteristic structures, thereby realizing the simultaneous bonding of different layers of materials and step-by-step stamping, avoiding wrinkling or tearing defects caused by a single stamping on the workpiece. The device realizes the heating of metal parts, the composite of dissimilar materials and multiple stamping, shortens the process flow, and improves production efficiency. The process flow is short, the energy consumption is low, the composite interface strength is good, and the forming precision is high.

[0020] In addition to the above-described purposes, features and advantages, the present invention has other purposes, features and advantages. The present invention will be further described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The drawings constituting a part of this application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0022] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0023] Figure 2 It is a partial cross-sectional view of the demoulding top column;

[0024] Figure 3 It is a structural diagram of the bottom mold;

[0025] Figure 4 yes Figure 3 Schematic diagram of the decomposed state structure;

[0026] Figure 5 yes Figure 4 A magnified view of point A;

[0027] Figure 6 It is a structural schematic diagram of the molded part;

[0028] Figure 7 yes Figure 6 A magnified view of point B;

[0029] Figure 8 It is a structural schematic diagram of the demoulding top column;

[0030] Fig. 9 It is a structural schematic diagram of the demoulding top column from another perspective;

[0031] Fig.10 It is a structural schematic diagram of the first state during the processing;

[0032] Fig.11 It is a structural schematic diagram of the second state during the processing;

[0033] Fig.12 It is a structural schematic diagram of the third state during the processing;

[0034] Fig.13 This is a schematic diagram of a workpiece after forming in one embodiment.

[0035] Legend:

[0036] Bottom mold 100, upper metal plate 101, lower metal plate 102, pressure sensor 103, temperature sensor 104, molding surface 110, through hole 111, bottom hole 112, shoulder surface 113, reinforcing rib 114, groove 120, base 130, first annular groove 131, abutting surface 132, connecting hole 133, molding part 140, connecting column 141;

[0037] Edge pressing electrode 200;

[0038] Upper die 300, pressing surface 310;

[0039] Electromagnetic pulse coil 400;

[0040] Demolding top column 500, bottom column 510, avoidance strip 511, second annular groove 512, force unloading surface 513, and extension column 520;

[0041] Compression spring 600;

[0042] The edge pressing seat 700 and the fixed electrode 710 .

[0043] Insulation seat 800. DETAILED DESCRIPTION

[0044] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0045] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0046] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0047] In addition, the descriptions of "first", "second", etc. in the present invention are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0048] Please refer to Figure 1 In a preferred embodiment of the present invention, an electromagnetic impact heterogeneous metal plate composite stamping integrated forming device includes a bottom die 100, a clamping electrode 200, an upper die 300, and an electromagnetic pulse coil 400.

[0049] A molding surface 110 is provided at the upper end of the bottom mold 100 , and a concave groove 120 is provided on the molding surface 110 . The distribution position and number of the grooves 120 are set according to the contour of the workpiece (the upper metal plate 101 and the lower metal plate 102 ) to be processed.

[0050] The edge holding electrode 200 is movable above the bottom die 100, and is used to press the edge of the upper metal plate 101 and electrically heat the upper metal plate 101. The edge holding electrode 200 can be driven to rise and fall by a hydraulic cylinder, and the telescopic shaft of the hydraulic cylinder is made of non-conductive material or the telescopic shaft is insulated from the edge holding electrode 200. Two edge holding electrodes 200 are provided, and the two edge holding electrodes 200 are respectively connected to the positive and negative poles of the power supply through wires.

[0051] The upper mold 300 is movable up and down above the bottom mold 100, and a clamping surface 310 adapted to the forming surface 110 is provided at the bottom of the upper mold 300. The clamping surface 310 is used to cooperate with the forming surface 110 to stamp the upper metal plate 101 and the lower metal plate 102, and to fit and press the upper metal plate 101 and the lower metal plate 102 together.

[0052] The electromagnetic pulse coil 400 is installed on the upper mold 300. The electromagnetic pulse coil 400 is used to apply a high-speed electromagnetic impact load to the upper metal plate 101 and the lower metal plate 102, so that the upper metal plate 101 and the lower metal plate 102 are convex toward the groove 120, and the lower metal plate 102 is in contact with the groove wall of the groove 120. The electromagnetic pulse coil is a device that uses electromagnetic pulse technology. Its working principle is based on the fact that when a conductor with current is placed in a magnetic field, the conductor will be acted upon by a force called the Lorentz force. The characteristics of this impact force are that the action time is extremely short and the magnitude can reach a large value.

[0053] The present invention provides an electromagnetic impact heterogeneous metal plate composite stamping integrated forming device, which uses a clamping electrode 200 to clamp the edge of the upper metal plate and electrically heat the upper metal plate 101, so that the metal plate is electrically heated while the edge of the metal plate is clamped, so that during stamping, the fluidity and plasticity of the metal are stronger, the defects such as wrinkling, tearing and micro cracks of the material produced by stamping are smaller, and the workpiece rebounds less after forming, and the forming accuracy is higher, so that the interface strength and forming quality of the workpiece are guaranteed. After heating, the clamping surface 310 of the upper mold 300 is pressed down so that the clamping surface 310 cooperates with the forming surface 110 to stamp the upper metal plate 101 and the lower metal plate 102. After the metal plate basic structure is stamped and formed , and then the electromagnetic pulse coil is energized to apply high-speed electromagnetic impact force to the upper metal plate 101 and the lower metal plate 102, so that the upper metal plate 101 and the lower metal plate 102 achieve interface bonding under the coupling of high temperature and high-speed transient electromagnetic impact force, and at the same time, the protrusion toward the groove 120 fits with the groove wall of the groove 120 to achieve the bonding of two layers of metal and the stamping forming of local small feature structures, thereby achieving the simultaneous bonding of different layers of materials and step-by-step stamping, avoiding wrinkling or tearing defects caused by a single stamping on the workpiece. The device realizes the heating of metal parts, the composite of different materials and multiple stamping, shortens the process flow, and improves production efficiency. The process flow is short, the energy consumption is low, the composite interface strength is good, and the forming precision is high.

[0054] Reference Figure 1 and Figure 2In some embodiments of the present invention, a demoulding pin 500 is further included. The demoulding pin 500 is elastically mounted on the bottom mold 100. The demoulding pin 500 has an ejection state protruding from the molding surface 110 and a molding state flush with the molding surface 110. The demoulding pin 500 in the molding state is against the bottom mold 100 so as to transmit the force from top to bottom to the bottom mold 100. The demoulding pin 500 in the molding state is subjected to an elastic force moving toward the ejection state. It can be understood that the demoulding pin 500 is flush with the molding surface 110, and the top surface of the demoulding pin 500 is adapted to the required molding contour of the workpiece at this position. At this time, the top of the demoulding pin 500 also serves as a component of the mold for molding the workpiece surface. Of course, the contour of the top of the demoulding pin 500 is usually a complete plane or curved surface, which will avoid the position of the complex contour of the workpiece. In the forming state, the demoulding top pin 500 is flush with the forming surface 110, which does not affect the forming of the workpiece, and the demoulding top pin 500 in the forming state is against the bottom mold 100, so that the force from top to bottom can be transmitted to the bottom mold 100, so that the demoulding top pin 500 in the forming state can withstand a larger forming pressure, ensure the forming effect of the workpiece at this position, and avoid abnormal protrusions of the workpiece at this position. When the forming is completed and the upper mold 300 moves upward, the demoulding top pin 500 can provide a certain elastic force to automatically lift the workpiece, which is convenient for demoulding. Even if the demoulding top pin 500 cannot lift the workpiece, it can make the workpiece easier to demould.

[0055] Reference Figure 2 In a further embodiment of the present invention, the demoulding top column 500 includes a bottom column 510 and a protruding column 520 connected to the upper end of the bottom column 510, and the cross-sectional profile of the bottom column 510 is larger than that of the protruding column 520; the molding surface 110 is provided with a through hole 111 extending downward, and it can be understood that the edge of the top surface of the demoulding top column 500 is adapted to the upper edge of the through hole 111 to ensure the molding quality of the workpiece surface, and the protruding column 520 is adapted to the through hole 111 and is movably penetrated in the through hole 111; the bottom of the through hole 111 is connected to a bottom hole 112 with a profile larger than that of the through hole 111, and the upper end of the bottom hole 112 and the lower end of the through hole 111 form a shoulder surface 113; the bottom column 510 is adapted to the profile of the bottom hole 112. The upper end surface of the bottom column 510 in the ejected state contacts the shoulder surface 113; the bottom of the bottom column 510 is installed with a compression spring 600. The shoulder surface 113 is used to limit the upward movement of the bottom column 510. The outline of the bottom column 510 is larger than the through hole 111, so that the bottom column 510 will not pass through the through hole 111, and the bottom column 510 will not fall off under the action of the elastic force.

[0056] Reference Figure 2 , Figure 7 , Figure 8 and Fig. 9In a further embodiment of the present invention, a reinforcing rib 114 is provided between the shoulder surface 113 and the peripheral wall of the bottom hole 112; the bottom column 510 is provided with an escape strip 511 for the reinforcing rib 114 to be embedded in, and the thickness of the reinforcing rib 114 is adapted to the width of the escape strip 511; in the ejection state and the forming state, the reinforcing rib 114 is at least partially embedded in the escape strip 511. The reinforcing rib 114 can improve the structural strength of the upper structure of the shoulder surface 113, so as to improve the structural strength and life under strong impact. In addition, the thickness of the reinforcing rib 114 is matched with the width of the avoidance strip 511, which can guide and position the lifting and lowering activities of the demolding top column 500 and prevent the demolding top column 500 from circumferential rotation. In particular, when the top surface of the demolding top column 500 is an arc surface, the rotation of the demolding top column 500 will cause the top surface of the demolding top column 500 to be misaligned, so that the edge of the top surface of the demolding top column 500 does not match the upper edge of the through hole 111, and the top of the demolding top column 500 will not be flush with the forming surface 110, thereby affecting the surface forming of the workpiece.

[0057] Reference Figure 3 , Figure 4 , Figure 5 and Figure 6 In a further embodiment of the present invention, the bottom mold 100 includes a base 130 and a molding member 140 detachably connected to the top of the base 130. The molding member 140 is independently arranged from the base 130, so as to facilitate the installation of components such as the bottom column 510 and the compression spring 600. The molding surface 110, the groove 120, the through hole 111 and the bottom hole 112 are all formed on the molding member 140. The bottom of the base 130 is provided with a first annular groove 131 for the compression spring 600 to be embedded. The inner side and the outer side of the upper end of the first annular groove 131 are formed with abutment surfaces 132. The bottom of the bottom column 510 is provided with a second annular groove 512 for the compression spring 600 to be embedded. Thus, the first annular groove 131 and the second annular groove 512 are used to realize the installation and positioning of the compression spring 600. The inner side and the outer side of the lower end of the second annular groove 512 are formed with a force-releasing surface 513 for contacting the abutment surface 132.

[0058] Reference Figure 4 The base 130 is provided with a connecting hole 133, and the bottom of the molded part 140 is provided with a connecting column 141 passing through the connecting hole 133. A threaded shaft is provided at the bottom of the connecting column 141 passing through the connecting hole 133, and the threaded shaft is connected with a connecting nut, so as to connect and fix the base 130 and the molded part 140. A countersunk groove can be provided at the lower end of the connecting hole 133 to accommodate the connecting nut.

[0059] Reference Figure 8 and Fig. 9In a further embodiment of the present invention, the avoidance strip 511 is connected to the second annular groove 512 to allow air to flow on the upper and lower sides of the bottom column 510, so that when the demoulding top column 500 is raised and lowered, the air on the upper and lower sides of the bottom column 510 can flow, avoiding the increase in movement resistance caused by compressed air due to the movement in the closed space, and making the air pressure on both sides of the bottom column 510 equal, avoiding the air pressure affecting the movement of the demoulding top column 500. It can be understood that if the avoidance strip 511 is not connected to the second annular groove 512, since the bottom column 510 is adapted to the contour of the bottom hole 112, and the protruding column 520 is adapted to the outlet hole 111, it is difficult for air to flow from the gap between the bottom column 510 and the bottom hole 112 and the gap between the protruding column 520 and the outlet hole 111. The upper side of the bottom column 510 and the shoulder surface 113 will form a nearly sealed space, and the lower side of the bottom column 510 will also form a nearly sealed space. As a result, when the bottom column 510 moves up and down, one side will compress the space and the other side will dilute the space, and the movement resistance of the bottom column 510 is relatively large. The connection between the avoidance strip 511 and the second annular groove 512 can well avoid this problem, and is conducive to the optimization of the existing structure itself, and the structure is simpler and more clever.

[0060] Reference Figure 1 In a further embodiment of the present invention, a pressure seat 700 is provided on the periphery of the bottom mold 100, and a fixed electrode 710 is provided on the upper end of the pressure seat 700. The fixed electrode 710 is used to contact the bottom edge of the lower metal plate 102 and energize and heat the lower metal plate 102, thereby avoiding insufficient energization and heating of the lower metal plate 102 by the pressure electrode 200. An insulating structure can be provided between the pressure seat 700 and the fixed electrode 710 to achieve insulation between the two. In order to avoid conducting electricity to other structures, an insulating seat 800 can be provided at the bottom of the bottom mold 100. Two fixed electrodes 710 are provided, and the two fixed electrodes 710 are respectively connected to the positive and negative poles of the power supply through wires.

[0061] In order to detect the pressure, a pressure sensor 103 may be installed on the upper mold pressing surface 310 , and in order to monitor the temperature, a temperature sensor 104 may be installed on the fixed electrode 710 or the edge pressing electrode 200 .

[0062] The present invention also provides an electromagnetic impact heterogeneous metal plate composite stamping integrated forming method, which is implemented based on an electromagnetic impact heterogeneous metal plate composite stamping integrated forming device, and includes steps S1, S2, S3, S4, and S5.

[0063] S1, placing the upper metal plate 101 and the lower metal plate 102 on the upper end of the bottom mold 100.

[0064] S2, after the edge pressing electrode 200 presses the upper metal plate 101 and the lower metal plate 102, the heating power source is turned on to supply power to the edge pressing electrode 200, so that the upper metal plate 101 and the lower metal plate 102 are electrically heated. Specifically, the edge pressing electrode 200 and the fixed electrode 710 are both powered on to heat the upper metal plate 101 and the lower metal plate 102.

[0065] S3, the upper die 300 moves downward to press the upper metal plate 101 and the lower metal plate 102 tightly against the forming surface 110. The upper die 300 is usually pushed by a hydraulic cylinder. First, the upper die 300 moves downward to Fig.10 In the state shown in FIG. 1 , the edges of the upper metal plate 101 and the lower metal plate 102 are clamped and fixed by the edge clamping electrode 200 and the fixed electrode 710, and then the upper die 300 continues to move downward to stamp and deform the upper metal plate 101 and the lower metal plate 102 until they are attached to the forming surface 110, achieving Fig.11 In the state shown, the demoulding ejector pin 500 is in a molding state.

[0066] S4, the electromagnetic pulse coil 400 is energized, and the electromagnetic pulse coil 400 generates a huge pulse electromagnetic force, which impacts the upper metal plate 101 and the lower metal plate 102, so that the upper metal plate 101 and the lower metal plate 102 bulge toward the groove 120, and the lower metal plate 102 fits with the groove wall of the groove 120, achieving Fig.12 Status shown.

[0067] S5, the edge holding electrode 200 is lifted up, the upper metal plate 101 and the lower metal plate 102 are released from the pressing, and the upper metal plate 101 and the lower metal plate 102 are taken out. It can be understood that after the edge holding electrode 200 is lifted up, the demoulding ejector pin 500 can automatically restore to the ejection state of the protruding molding surface 110, thereby lifting the workpiece for easy removal.

[0068] Reference Fig.13 , is a workpiece processed and formed in an embodiment, the upper metal plate 101 is made of aluminum alloy, and the lower metal plate 102 is made of magnesium alloy.

[0069] In some embodiments of the present invention, in step S2, the upper metal plate 101 and the lower metal plate 102 need to be powered on and heated to a preset temperature and kept warm for a preset time. Specifically, the upper metal plate 101 and the lower metal plate 102 are heated to 400°C and kept warm for 10 minutes, and then the edge pressing electrode 200 and the fixed electrode 710 are powered off and the next step is performed.

[0070] In some embodiments of the present invention, the heating process of the upper metal plate 101 and the lower metal plate 102 is controlled according to the following formula:

[0071] ;

[0072] is the proportionality coefficient, for The integration coefficient at time, is the differential coefficient, is the current required temperature; is a recurrent neural network model, for Heater power parameters at the moment, for The influencing parameters of the moment, for The temperature of the moment, for The accumulated heating time at all times, for The output signal of the PID regulator at that moment.

[0073] Specifically, the closed-loop feedback control of the temperature T can be realized by using the recurrent neural network RNN1 and PID with the heater power and other heater parameters (W, P). RNN1 is used to learn the dynamic characteristics of the temperature T changing over time, and PID is used to adjust the control signal in real time to make the temperature T reach the ideal value (required value). W is the heater power, and P is other heater parameters, such as the switch opening.

[0074] The neural network control part establishes the dynamic response of the temperature system through the recurrent neural network RNN1 to describe the characteristics of temperature changes over time. Since the temperature control is through the heater, the mapping relationship between the heater power and other related heater parameters and the corresponding temperature is established. First, the temperature parameter sequence in the historical processing process is obtained through the temperature sensor:

[0075] ;

[0076] in For the insulation process The actual temperature at the moment, =1,2,…,n, where n is the total number of sequences.

[0077] Then, obtain the heater power parameters and other parameter sequences during the historical processing:

[0078] ;

[0079] in For the insulation process The actual heater power at the moment, For the insulation process Other relevant parameters of the actual heater at the moment (such as switch opening, etc.).

[0080] The neural network training data set containing historical processing temperature data and power data is:

[0081] ;

[0082] The input of RNN1 is the heater power parameter and other parameters , the output parameter is the corresponding temperature parameter . Then the learning goal of RNN1 is to learn a mapping function:

[0083] ;

[0084] Establish the RNN1 neural network model, construct the structure of RNN1 through Pytorch, the number of hidden nodes of RNN1 and the input sequence The dimensions are consistent with Consistent, the output size is Consistent, In addition, the input of RNN1 contains the current control input , also includes the temperature at the previous moment , the input vector is corrected to . Then the RNN1 neural network model is:

[0085] ;

[0086] in To predict temperature.

[0087] Then the forward propagation of RNN1 is described as:

[0088] ;

[0089] ;

[0090] in is the time step The hidden output of is the time step The hidden output of is the selected activation function, and is the weight matrix of the intermediate layer of the neural network, is the weight matrix of the neural network output layer, and is the neural network bias term.

[0091] Finally, train the network RNN1 and use the Adam optimizer in Pyorch to optimize the output temperature prediction value by minimizing the mean square error. and actual temperature value The gap between , then the constructed RNN1 loss function is:

[0092] ;

[0093] The temperature is controlled by PID. First, the neural network RNN1 of S1 predicts the current heater parameters. Temperature .

[0094] Then calculate the temperature deviation , the predicted temperature and the current desired temperature By comparison, we can get the temperature deviation:

[0095] ;

[0096] The output signal of PID control is for:

[0097] .

[0098] PID control input Corresponding to the heater power and other parameters , and neural network RNN1 together to achieve closed-loop control of temperature.

[0099] The method can also control the electromagnetic force and current during the discharge process.

[0100] Use MPC model predictive control to adjust the current A so that the electromagnetic force Q reaches the expected range; based on the particle swarm algorithm, optimize the electromagnetic force weight in MPC and current weight .

[0101] Design an MPC controller. MPC minimizes the cost function by optimizing the control input sequence. The cost function of MPC is designed as:

[0102] ;

[0103] ;

[0104] in To predict the electromagnetic forming force at the jth moment, The electromagnetic forming force for the target, is the current at the jth moment, is the current of the previous step, is the weight term of electromagnetic force control, is the weight term for current control. for and The mapping function of .

[0105] The selection of weight terms is transferred to a multi-objective optimization problem, and the electromagnetic force weight terms in MPC control are optimized by particle swarm optimization. and the current weight term , make the control system more stable and improve the performance of the control system, is the cost function value, is the optimization objective function, and the minimum value is the optimal solution.

[0106] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An electromagnetic impact heterogeneous metal plate composite stamping integrated forming device, characterized in that: include: A bottom mold (100) is provided with a molding surface (110) at the upper end, and a concave groove (120) is provided on the molding surface (110); The edge pressing electrode (200) is movable in a lifting manner above the bottom mold (100) and is used to press the edge of the upper metal plate (101) and electrically heat the upper metal plate (101); The upper die (300) is movable in a lifting manner above the bottom die (100), and a pressing surface (310) adapted to the forming surface (110) is provided at the bottom, wherein the pressing surface (310) is used to cooperate with the forming surface (110) to stamp and form the upper metal plate (101) and the lower metal plate (102); The electromagnetic pulse coil (400) is mounted on the upper mold (300) and is used to apply a high-speed electromagnetic impact load to the upper metal plate (101) and the lower metal plate (102), so that the upper metal plate (101) and the lower metal plate (102) protrude toward the groove (120), and the lower metal plate (102) is fitted with the groove wall of the groove (120); it also includes a demoulding top column (500), the demoulding top column (500) is elastically mounted on the bottom mold (100), and the demoulding top column (500) has an ejection state protruding from the molding surface (110) and a molding state flush with the molding surface (110); the demoulding top column (500) in the molding state is against the bottom mold (100) so as to transmit the force from top to bottom to the bottom mold (100), and the demoulding top column (500) in the molding state is subjected to an elastic force moving toward the ejection state.

2. The electromagnetic impact heterogeneous metal plate composite stamping integrated forming device according to claim 1 is characterized in that: The demoulding ejector column (500) comprises a bottom column (510) and a protruding column (520) connected to the upper end of the bottom column (510), wherein the cross-sectional profile of the bottom column (510) is larger than that of the protruding column (520); the molding surface (110) is provided with a through hole (111) extending downward, and the protruding column (520) is adapted to the through hole (111) and is movably arranged in the through hole (111); the bottom of the through hole (111) is connected to a bottom hole (112) having a profile larger than that of the through hole (111), and a shoulder surface (113) is formed between the upper end of the bottom hole (112) and the lower end of the through hole (111); the bottom column (510) is adapted to the profile of the bottom hole (112); the upper end surface of the bottom column (510) in the ejected state contacts the shoulder surface (113); and a compression spring (600) is installed at the bottom of the bottom column (510).

3. The electromagnetic impact heterogeneous metal plate composite stamping integrated forming device according to claim 2 is characterized in that: A reinforcing rib (114) is provided between the shoulder surface (113) and the peripheral wall of the bottom hole (112); the bottom column (510) is provided with an escape strip opening (511) for the reinforcing rib (114) to be embedded in, and the thickness of the reinforcing rib (114) is adapted to the width of the escape strip opening (511); in both the ejection state and the forming state, the reinforcing rib (114) is at least partially embedded in the escape strip opening (511).

4. The electromagnetic impact heterogeneous metal plate composite stamping integrated forming device according to claim 3 is characterized in that: The bottom mold (100) comprises a base (130) and a molding piece (140) detachably connected to the top of the base (130); the molding surface (110), the groove (120), the through hole (111) and the bottom hole (112) are all formed on the molding piece (140); a first annular groove (131) for embedding a compression spring (600) is provided at the bottom of the base (130); abutment surfaces (132) are formed on the inner and outer sides of the upper end of the first annular groove (131); a second annular groove (512) for embedding a compression spring (600) is provided at the bottom of the bottom column (510); a force-releasing surface (513) for contacting the abutment surface (132) is formed on the inner and outer sides of the lower end of the second annular groove (512).

5. The electromagnetic impact heterogeneous metal plate composite stamping integrated forming device according to claim 4 is characterized in that: The avoidance strip opening (511) is in communication with the second annular groove (512), so that air can flow on the upper and lower sides of the bottom column (510).

6. The electromagnetic impact heterogeneous metal plate composite stamping integrated forming device according to claim 1 is characterized in that: A pressure edge seat (700) is provided on the outer periphery of the bottom mold (100), and a fixed electrode (710) is provided on the upper end of the pressure edge seat (700). The fixed electrode (710) is used to contact the bottom edge of the lower metal plate (102) and electrically heat the lower metal plate (102).

7. An electromagnetic impact heterogeneous metal plate composite stamping integrated forming method, implemented based on the electromagnetic impact heterogeneous metal plate composite stamping integrated forming device according to any one of claims 1 to 6, characterized in that: The steps include: S1, placing an upper metal plate (101) and a lower metal plate (102) on the upper end of a bottom mold (100); S2, after the edge pressing electrode (200) presses the upper metal plate (101) and the lower metal plate (102), the heating power source is turned on to supply power to the edge pressing electrode (200), so that the upper metal plate (101) and the lower metal plate (102) are electrically heated; S3, the upper mold (300) moves downward to press the upper metal plate (101) and the lower metal plate (102) tightly against the molding surface (110); S4, energizing the electromagnetic pulse coil (400), so that the electromagnetic pulse coil (400) generates a huge pulse electromagnetic force, which impacts the upper metal plate (101) and the lower metal plate (102), so that the upper metal plate (101) and the lower metal plate (102) bulge toward the groove (120), and the lower metal plate (102) fits against the groove wall of the groove (120); S5, the edge pressing electrode (200) is lifted up to release the pressing of the upper metal plate (101) and the lower metal plate (102), and the upper metal plate (101) and the lower metal plate (102) are taken out.

8. The electromagnetic impact heterogeneous metal plate composite stamping integrated forming method according to claim 7 is characterized in that: In step S2, the upper metal plate (101) and the lower metal plate (102) need to be powered on and heated to a preset temperature and kept warm for a preset time.

9. The electromagnetic impact heterogeneous metal plate composite stamping integrated forming method according to claim 7 is characterized in that: The heating process of the upper metal plate (101) and the lower metal plate (102) is controlled according to the following formula: ； is the proportionality coefficient, for The integration coefficient at time, is the differential coefficient, is the current required temperature; is a recurrent neural network model, for Heater power parameters at the moment, for The influencing parameters of the moment, for The temperature of the moment, for The accumulated heating time at all times, for The output signal of the PID regulator at that moment.

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