Electromagnetic drive hydraulic blanking-flanging integrated forming device and machining method

Abstract

The invention belongs to the technical field of plate electromagnetic forming, and discloses an electromagnetic drive hydraulic blanking-flanging integrated forming device which comprises a straight hole blanking female die and a punch which are used in cooperation. The pressure bin is connected with the punch in a sealed mode and forms a cavity used for containing liquid or gas. A cutting edge of the straight hole blanking female die directly faces liquid or gas contained in the cavity; a plate to be machined is located between the cutting edge of the straight hole blanking female die and the pressure bin. The forming coil is arranged at the bottom of the punch; the forming coil comprises an insulating block and an electromagnetic coil fixed to the insulating block, the electromagnetic coil is connected with a pulse current loop through a wire, the forming coil discharges to generate electromagnetic force to drive liquid or gas to impact a to-be-machined plate, and the to-be-machined plate is cut off by the cutting edge of the female die and continuously impacted by the liquid or gas to achieve flanging and attaching to the die edge to achieve film pasting. The invention further provides a machining method for machining the plate through the device. The device and the method have the advantages of high shape control capability and high forming precision.

Description

Technical Field

[0001] The invention relates to the technical field of electromagnetic forming, and in particular to an electromagnetic driven hydraulic punching-flanging integrated forming device and a processing method. Background Art Flanging is a forming process that processes the straight or curved edge of a sheet into a vertical edge or an angled edge. It can change the shape of the metal sheet, strengthen the edge of the sheet and improve the strength of the parts. It is used in important occasions such as aircraft door panels and fuel tanks. At present, the forming method of flanging parts is mainly traditional cold stamping, that is, the sheet is fixed between the blank holder and the straight hole punching die at room temperature, and the punch presses the sheet into the straight hole punching die to realize the flanging of the part. However, the mold cost involved in cold stamping is relatively high, especially for alloys with high yield strength. A large amount of residual stress can easily cause the part to rebound, and the punch can easily cause scratches on the surface of the part during the impact process. Insufficient lubrication conditions can easily lead to part breakage. In addition, the part must be pre-processed into a circular hole shape before flanging, which increases the process and forming errors.

[0002] Compared with traditional stamping processes, electromagnetic forming technology mainly relies on non-contact electromagnetic force to achieve sheet deformation, which can effectively avoid surface damage caused by the stamping process, and at the same time, the inertia effect can be used to increase the material forming height. However, the electromagnetic force usually decays rapidly during electromagnetic forming, and the forming accuracy of parts is difficult to control. In addition, the electromagnetic coil is also limited by the smaller forming area of ​​the flanged parts. The smaller number of coil turns results in a smaller electromagnetic force. Increasing the electromagnetic force by increasing the voltage will increase equipment costs, easily cause coil damage, and have poor safety. At the same time, traditional electromagnetic stamping coils have poor universality, and one coil can usually only form parts of one shape or size. For metals such as titanium alloys with poor conductivity, it is difficult to achieve their forming with a single electromagnetic forming method. Summary of the invention

[0003] The technical problem to be solved by the present invention is to overcome the deficiencies and defects mentioned in the above background technology and provide an electromagnetic driven hydraulic punching-flanging integrated forming device and processing method with strong shape control ability and high forming accuracy. In order to solve the above technical problems, the technical solution proposed by the present invention is: an electromagnetic driven hydraulic punching-flanging integrated forming device, comprising: Straight hole punching dies and punches used in conjunction with each other; A pressure chamber, which is sealed and connected to the punch and forms a cavity for containing liquid or gas; The cutting edge of the straight hole punching die faces the liquid or gas contained in the cavity; The plate to be processed is located between the cutting edge of the straight hole punching die and the pressure chamber; The forming coil is arranged at the bottom of the punch; the forming coil includes an insulating block and an electromagnetic coil fixed on the insulating block. The electromagnetic coil is connected to a pulse current loop through a wire. The discharge of the forming coil generates an electromagnetic force to drive liquid or gas to impact the sheet to be processed. The sheet to be processed is cut by the die edge and continuously subjected to the impact force of the liquid or gas to achieve flanging and die bonding.

[0004] In one embodiment, the shape of the cutting edge is rectangular or at least one side is inclined in the vertical direction, the bottom of the straight hole punching die where the cutting edge is located is a plane or a curved surface, and the straight hole punching die includes a fixed part and a split die working part, and the split die working part is a detachable part.

[0005] In one embodiment, a heating device is provided at the bottom edge of the straight hole punching die near the cutting edge.

[0006] In one embodiment, a bulging coil is provided at the bottom edge of the straight hole punching die close to the cutting edge, and a ring is provided outside the bulging coil. When the bulging coil is energized, the ring deforms and moves away from the bulging coil to squeeze the liquid or gas.

[0007] In one embodiment, the punch includes an annular punch and a guide column arranged in the annular punch, the guide column extends to the bottom edge of the straight hole punching die, and the annular punch moves up and down along the guide column; the annular punch and the guide column form an annular cavity, and the liquid or gas is placed in the annular cavity.

[0008] In one embodiment, when the plate to be processed is an aluminum alloy, the pressure chamber is connected to a cooling device, and the cooling device is used to reduce the temperature of the liquid or gas in the pressure chamber to an ultra-low temperature.

[0009] A processing method of an electromagnetically driven hydraulic punching-flanging integrated forming device, using the electromagnetically driven hydraulic punching-flanging integrated forming device as described above, comprises the following steps: S1: Place the sheet to be processed between the straight hole punching die and the punch; S2: The pulse current loop of the electromagnetic coil is turned on, and the discharge generates electromagnetic force to make the punch move upward, thereby driving the liquid or gas to impact the sheet to be processed. The sheet to be processed gradually bulges and becomes thinner at the edge of the straight hole punching die; S3 After the sheet to be processed is continuously impacted by liquid or gas, it breaks at the cutting edge of the straight hole punching die and is flanging and die-attaching due to the impact force of the liquid or gas.

[0010] In one embodiment, an electric current is passed through the expansion coil, and the liquid or gas is squeezed behind the annular member, thereby increasing the local pressure and making the flanged area of ​​the sheet material close to the die edge.

[0011] In one embodiment, before the pulse current loop of the electromagnetic coil is connected, the heating device is started to heat the plate to be processed.

[0012] In one embodiment, before the pulse current loop of the electromagnetic coil is turned on, a groove of a preset depth is formed on the plate to be processed opposite to the cutting edge.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows: the electromagnetic driven hydraulic punching-flanging integrated forming device of the present invention can directly realize the one-step forming of part punching and flanging, avoiding frequent mold replacement during the forming process, reducing the processing steps, improving the forming efficiency, and having high forming precision. The electromagnetic driven hydraulic punching-flanging integrated forming device of the present invention has better universality, and the driving device only needs one forming coil, and the flanging forming of various complex shapes can be realized by changing the shape of the cutting edge of the straight hole punching die; the number of turns of the forming coil can be increased to increase the electromagnetic force and liquid pressure, and it is suitable for most alloy materials, and does not need to set a driving plate with higher conductivity, thereby reducing material consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0015] Figure 1 It is a structural schematic diagram of an electromagnetic driven hydraulic punching-flanging integrated forming device according to one embodiment; 2(a) and 2(b) are schematic structural diagrams of an electromagnetically driven hydraulic punching-flanging integrated forming device according to another embodiment; Figure 3 It is a schematic diagram of the structure of a straight hole punching die of an electromagnetic driven hydraulic punching-flanging integrated forming device according to another embodiment; 4( a ) and 4( b ) are schematic diagrams of the cutting edge structure of an electromagnetically driven hydraulic punching-flanging integrated forming device according to one embodiment; 5( a ) and 5( b ) are schematic diagrams of the cutting edge structure of an electromagnetically driven hydraulic punching-flanging integrated forming device according to another embodiment; 6( a ) and 6( b ) are schematic diagrams of the cutting edge structure of an electromagnetically driven hydraulic punching-flanging integrated forming device according to another embodiment; Figure 7 It is a schematic diagram of the cutting edge shape and the corresponding product structure in different implementation modes; Figure 8 It is a schematic structural diagram of an electromagnetic driven hydraulic punching-flanging integrated forming device with a heating device according to one embodiment; 9( a ) and 9( b ) are schematic structural diagrams of an electromagnetically driven hydraulic punching-flanging integrated forming device according to another embodiment; 10( a ) and 10 ( b ) are schematic structural diagrams of an electromagnetically driven hydraulic punching-flanging integrated forming device according to another embodiment; Fig.11 It is a schematic structural diagram of an electromagnetically driven hydraulic punching-flanging integrated forming device with a cooling device according to another embodiment; FIG. 12 (a), FIG. 12 (b) and FIG. 12 (c) are schematic diagrams of a processing method using an electromagnetically driven hydraulic punching-flanging integrated forming device according to an embodiment; FIG. 13 ( a ) and FIG. 13 ( b ) are schematic diagrams showing a pre-grooved structure of a sheet material to be processed according to an embodiment.

[0016] Description of the drawings: 1. Straight hole punching die; 101. Cutting edge; 102. Bottom edge of straight hole punching die; 103. Fixed part of split die; 104. Working part of split die; 2. Plate to be processed; 3. Pressure chamber; 4. Liquid or gas; 5. Rubber gasket; 6. Punch; 7. Forming coil; 8. Insulating block; 9. Electromagnetic coil; 10. Heating device; 12. Guide column; 13. Ring punch; 14. Ring coil; 15. Cooling device; 16. Ring part; 17. Expanding coil. DETAILED DESCRIPTION

[0017] In order to facilitate the understanding of the present invention, the present invention will be described more comprehensively and meticulously below in conjunction with the accompanying drawings and preferred embodiments of the present invention, but the protection scope of the present invention is not limited to the following specific embodiments.

[0018] Unless otherwise defined, all professional terms used below have the same meanings as those generally understood by those skilled in the art. The professional terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the scope of protection of the present invention.

[0019] Unless otherwise specified, various raw materials, reagents, instruments and equipment used in the present invention can be purchased from the market or prepared by existing methods.

[0020] See also Figure 1-13. An electromagnetic driven hydraulic punching-flanging integrated forming device of one embodiment comprises: a straight hole punching die 1 and a punch 6 used in combination, a pressure chamber 3 located at the bottom 102 of the straight hole punching die, and a forming coil 7 arranged at the bottom of the pressure chamber 3. The pressure chamber 3 is sealed and connected to the punch 6 to form a cavity for holding liquid or gas, that is, the pressure chamber 3. When the forming coil 7 provides electromagnetic force, the air pressure or hydraulic pressure in the pressure chamber 3 is enhanced to push the sheet 2 to be processed upward toward the cutting edge 101. The cutting edge 101 of the straight hole punching die 1 is located at the bottom 102 of the straight hole punching die. The forming coil 7 is arranged at the bottom of the punch 6. The forming coil 7 comprises an insulating block 8 and an electromagnetic coil 9 fixed on the insulating block 8, and the electromagnetic coil 9 is connected to a pulse current loop through a wire. The forming coil 7 discharges and generates electromagnetic force to drive the liquid or gas to impact the sheet 2 to be processed, and the sheet 2 to be processed is cut by the cutting edge 101 and continuously subjected to the impact force of the liquid or gas to achieve flanging and close to the die edge to achieve film bonding.

[0021] The electromagnetic driven hydraulic punching-flanging integrated forming device can directly realize the one-step forming of part punching and flanging, avoiding frequent mold replacement during the forming process, reducing processing steps, improving forming efficiency, and high forming precision. The electromagnetic driven hydraulic punching-flanging integrated forming device has better universality, only requires one forming coil, and can realize flanging forming of various complex shapes by changing the shape of the cutting edge 101 of the straight hole punching die 1; the number of coil turns can be increased by improving the bottom structure of the punch 6, thereby increasing the electromagnetic force and liquid pressure, and is suitable for most alloy materials. There is no need to set a driving plate with higher conductivity, which reduces material consumption. The forming coil 7 can increase the number of coil turns to enhance the electromagnetic force.

[0022] Specifically, see Figure 1 In one embodiment, see FIG. 2 , the bottom of the straight hole punching die 1 where the cutting edge 101 is located is a plane ( Figure 1 ) or curved surface (FIG. 2), a straight or curved flanged part can be obtained. Preferably, in one embodiment, refer to Figure 3 , the straight hole punching die 1 includes a split die fixing portion 103 and a split die working portion 104, the split die working portion 104 includes the position of the cutting edge, and the split die working portion 104 is a detachable component. Due to the problem that the cutting edge 101 is easy to wear, the split die working portion 104 is disassembled in a detachable manner for replacement, and the split die working portion 104 can also be replaced according to different product shapes, which can reduce the cost caused by mold wear and realize the processing of products of multiple shapes. In one embodiment, an inflation port is opened on the pressure chamber 3, and when the impact force provided in the pressure chamber 3 is gas pressure, the pressure chamber 3 is first inflated.

[0023] In one embodiment, referring to FIG. 4 , the shape of the cutting edge 101 is rectangular or at least one side is inclined in the vertical direction. Of course, the cutting edge 101 may also have other shapes, and its specific shape is designed according to product requirements. For example, referring to FIG. 5-6 , the liquid or gas flows in the direction of the arrow. FIG. 5-6 shows that different shapes of the cutting edge 101 correspond to different movement directions of the liquid or gas. Figure 7 It is shown that different shapes of products are formed due to different shapes of the cutting edge 101. That is to say, the die-attaching device of the present application can control the flow direction of the liquid or gas by changing the angle of the cutting edge 101, and the pressure of the liquid or gas on the plate 2 to be processed is slightly different. In addition, the shape of the cutting edge 101 can be changed according to the needs of the product to realize the formation of flanged parts of different shapes. The actual shape of the cutting edge 101 is not limited to Figure 7 As shown, it can be designed according to product needs.

[0024] See also Figure 8 In one embodiment, preferably, a heating device 10 is provided at the bottom edge 102 of the straight hole punching die near the cutting edge 101. The heating device 10 can realize local heating of the sheet 2 to be processed, so that the material in the heated area softens, which is conducive to the punching of the sheet 2 to be processed to realize the flanging die.

[0025] Please refer to FIG. 9 . In one embodiment, preferably, a bulging coil 17 is provided at the bottom edge 102 of the straight hole punching die close to the cutting edge 101, and a ring 16 is provided outside the bulging coil 17. When the bulging coil 17 is energized, the ring 16 is deformed away from the bulging coil 17 to squeeze the liquid or gas. The bulging coil 17 drives the ring 16 to expand and deform, which can further squeeze the liquid or gas, thereby increasing the pressure of the local gas or liquid, and promoting a better die-attaching effect of the flanging area of ​​the plate 2 to be processed.

[0026] Please refer to Figure 10. In one embodiment, preferably, the punch 6 includes an annular punch 13 and a guide post 12 disposed in the annular punch 13. The guide post extends to the bottom edge 102 close to the straight hole punching die. The annular punch 13 moves up and down along the guide post 12. The annular punch 13 and the guide post 12 form an annular cavity, and the liquid or gas is placed in the annular cavity. When in use, the middle of the sheet material 2 to be processed is pressed by the guide post 12 and the straight hole punching die 1. The punch of this embodiment is selected to only impact the annular cavity or gas around the guide post 12. This structure can further increase the pressure of the sheet material 2 to be processed at the cutting edge 101, which is beneficial to the improvement of the cutting and die-fitting accuracy of the sheet material 2 to be processed.

[0027] See also Fig.11In one embodiment, preferably, when the plate 2 to be processed can be aluminum alloy, the pressure chamber 3 is connected with a cooling device 15, and the cooling device 15 is used to reduce the liquid or gas in the pressure chamber 3 to ultra-low temperature. Specifically, the cooling device 15 provides cold air through liquid nitrogen. This is because general alloys are more easily softened under high temperature conditions, but aluminum alloys will improve material plasticity and strength at ultra-low temperatures (close to liquid nitrogen ambient temperature).

[0028] In one embodiment, the insulating block 8 may be an insulating material block such as an epoxy block (epoxy resin), a nylon block, or a polytetrafluoroethylene block.

[0029] Please refer to FIG. 12 . In one embodiment, a method for processing a plate using the electromagnetic driven hydraulic punching-flanging integrated forming device includes the following steps: S1: placing the sheet 2 to be processed between the straight hole punching die 1 and the punch 6; S2: The pulse current loop of the electromagnetic coil 9 is turned on, and the discharge generates electromagnetic force to make the punch 6 move upward, thereby driving the liquid or gas to impact the sheet 2 to be processed, and the sheet 2 to be processed gradually bulges and becomes thinner at the cutting edge 101 of the straight hole punching die 1; S3: After being continuously impacted by the liquid or gas, the sheet material 2 to be processed is broken at the cutting edge 101 of the straight hole punching die 1 and is flanging and die-attaching due to the impact force of the liquid or gas.

[0030] Preferably, in one embodiment, current is passed through the expansion coil 17, and the annular member 16 squeezes the liquid or gas behind it, thereby increasing the local pressure and making the flanged area of ​​the sheet material 2 to be processed close to the die edge.

[0031] Preferably, in one embodiment, before the pulse current loop of the electromagnetic coil 9 is connected, the method further includes the step of starting the heating device 15 to heat the plate 2 to be processed.

[0032] Preferably, referring to FIG. 13 , in one embodiment, before the pulse current loop of the electromagnetic coil 9 is turned on, the process further includes the step of: opening a groove 201 of a preset depth at the position of the plate 2 to be processed opposite to the cutting edge 101 to obtain a pre-grooved plate, which is conducive to faster blanking of thicker or harder-to-break plates. Preferably, the groove of the preset depth is close to the side opposite to the die away from the cutting edge 101. This makes the die side longer, the die effect better, and the precision higher.

[0033] The electromagnetic driven hydraulic punching-flanging integrated forming device and method of the present invention can directly realize the one-step forming of part punching and flanging, avoid frequent mold replacement during the forming process, reduce the processing steps, and improve the forming efficiency; the electromagnetic driven hydraulic punching-flanging integrated forming device and method of the present invention have better universality, and only one forming coil 1 is required to realize flanging forming of various complex shapes by replacing the straight hole punching die 1 or the split die working part 104 of the straight hole punching die 1; by changing the forming angle of the cutting edge 101 of the straight hole punching die 1, the flow direction of the liquid or gas can be controlled, and the pressure in the forming area can be improved. distribution, and improve the die-fitting accuracy of the flanging parts; the number of coil turns can be increased by improving the bottom structure of the punch 6, thereby increasing the electromagnetic force, and the pressure on the liquid or gas is increased to ensure that the sheet 2 to be processed can be cut and improve the formability; the heating device 15 can achieve local heating of the sheet 2 to be processed to achieve a softening effect, and further improve the formability of the sheet 2 to be processed; it is suitable for most alloy materials, and there is no need to set a driving plate with higher conductivity, which reduces material consumption; and through the straight line or curve setting of the bottom edge 102 of the straight hole punching die, the forming of flat or curved parts and flat or curved flanging can be achieved simultaneously.

Claims

1. A plate electromagnetic driven hydraulic punching-flanging integrated forming device, characterized in that: include: Straight hole punching dies and punches used in conjunction with each other; A pressure chamber, which is sealed and connected to the punch and forms a cavity for containing liquid or gas; The cutting edge of the straight hole punching die faces the liquid or gas contained in the cavity; The plate to be processed is located between the cutting edge of the straight hole punching die and the pressure chamber; The forming coil is arranged at the bottom of the punch; the forming coil includes an insulating block and an electromagnetic coil fixed on the insulating block. The electromagnetic coil is connected to a pulse current loop through a wire. The forming coil discharges to generate electromagnetic force to drive liquid or gas to impact the sheet to be processed. The sheet to be processed is cut by the die edge and continuously subjected to the impact force of the liquid or gas to achieve flanging.

2. The electromagnetic driven hydraulic punching-flanging integrated forming device according to claim 1, characterized in that: The cutting edge is rectangular in shape or inclined on at least one side in the vertical direction. The bottom of the straight hole punching die where the cutting edge is located is a plane or a curved surface. The straight hole punching die includes a fixed part and a split die working part, and the split die working part is a detachable part.

3. The electromagnetic driven hydraulic punching and flanging integrated forming device according to claim 1, characterized in that: A heating device is provided at the bottom edge of the straight hole punching die near the cutting edge.

4. The electromagnetic driven hydraulic punching and flanging integrated forming device according to claim 1, characterized in that: A bulging coil is arranged at the bottom edge of the straight hole punching die close to the cutting edge, and a ring is arranged outside the bulging coil. When the bulging coil is energized, the ring is deformed and moves away from the bulging coil, thereby squeezing liquid or gas.

5. The electromagnetic driven hydraulic punching-flanging integrated forming device according to claim 1, characterized in that: The punch comprises an annular punch and a guide post arranged in the annular punch, the guide post extends to the bottom edge close to the straight hole punching die, and the annular punch moves up and down along the guide post; the annular punch and the guide post form an annular cavity, and liquid or gas is placed in the annular cavity.

6. The electromagnetic driven hydraulic punching and flanging integrated forming device according to claim 1, characterized in that: When the plate to be processed is aluminum alloy, the pressure chamber is connected with a cooling device, and the cooling device is used to reduce the temperature of the liquid or gas in the pressure chamber to an ultra-low temperature.

7. A processing method of an electromagnetic driven hydraulic punching-flanging integrated forming device, characterized in that: The electromagnetic driven hydraulic punching-flanging integrated forming device as claimed in any one of claims 1 to 6 comprises the following steps: S1: Place the sheet to be processed between the straight hole punching die and the punch; S2: The pulse current loop of the electromagnetic coil is turned on, and the discharge generates electromagnetic force to make the punch move upward, thereby driving the liquid or gas to impact the sheet to be processed. The sheet to be processed gradually bulges and becomes thinner at the edge of the straight hole punching die; S3 The sheet to be processed is continuously impacted by liquid or gas and then breaks at the cutting edge of the straight hole punching die and is flanging-formed by the impact force of the liquid or gas.

8. The processing method according to claim 7, characterized in that: Electric current is passed through the bulging coil, and the liquid or fluid is squeezed behind the ring, thereby increasing the local pressure and making the flange area of ​​the sheet close to the die edge.

9. The processing method according to claim 7, characterized in that: Before the pulse current loop of the electromagnetic coil is connected, the heating device is started to heat the plate to be processed.

10. The processing method according to claim 7, characterized in that: Before the pulse current loop of the electromagnetic coil is connected, a groove of a preset depth is opened on the plate to be processed opposite to the cutting edge.

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