Plate flanging method and device using L-shaped magnetic field converter

Abstract

The present invention relates to a plate flanging method using an L-shaped magnetic field converter, comprising: making an L-shaped magnetic field converter; fixing the plate to be flanging by using a flange clamp and placing the magnetic field converter; arranging a driving coil under the base of the magnetic field converter; placing a die above the flange clamping area of ​​the plate to be flanging and fixing it; connecting the driving coil to a pulse power supply via a discharge switch; controlling the discharge switch to power the driving coil, generating induced eddy currents in the L-shaped magnetic field converter and the to-be-formed area of ​​the plate to be flanging, causing the to-be-formed area of ​​the plate to run toward the die, and completing the flanging of the plate. The present invention also discloses a plate flanging device. The present invention greatly increases the flanging angle of the plate, and by designing magnetic field converters with different base outer diameters and convex ring heights, different radial electromagnetic forces and axial electromagnetic forces are loaded in the flanging area of ​​the plate during the plate flanging process, thereby improving the flanging efficiency and forming quality of the plate.

Description

Technical Field

[0001] The invention belongs to the field of electromagnetic forming control of metal workpieces, and in particular relates to a plate flanging method and a device using an L-shaped magnetic field converter. Background Art

[0002] Various processed parts made of sheet metal are widely used in aerospace, automotive industry and other fields. Sheet metal flanging is an important processing technology in sheet metal forming.

[0003] In the existing plate flanging technology, a radial driving coil is usually used to provide axial electromagnetic force loading, and the plate flanging angle is difficult to reach above 45°. The invention with publication number CN107116128B, "A plate electromagnetic flanging device and method with axial-radial electromagnetic force time-sharing loading", provides a plate flanging method with axial electromagnetic force and radial electromagnetic force time-sharing loading. The invention with publication number CN111468589B, "Workpiece flanging analysis and control method with separated radial and axial electromagnetic forces", provides a workpiece flanging control method with separated axial electromagnetic force and radial electromagnetic force. The plate flanging angles of the above-mentioned plate flanging methods are all within 45°. Summary of the invention

[0004] The technical problem of the present invention is that the existing plate flanging method is difficult to achieve a flanging angle of more than 45°, and the drive coil requires an extremely high voltage to generate the current required for plate flanging, which seriously affects the service life of the drive coil.

[0005] The purpose of the present invention is to address the above-mentioned problems and to provide a plate flanging method and device using an L-shaped magnetic field converter, design a magnetic field converter with an L-shaped cross-section, and manufacture magnetic field converters with different outer diameters and heights, thereby achieving the loading of radial electromagnetic force and axial electromagnetic force in different proportions in the flanging area of ​​the plate, reducing the difficulty of flanging the plate, increasing the flanging angle, and reducing the current of the driving coil.

[0006] The technical solution of the present invention is a plate flanging method using an L-shaped magnetic field converter, wherein the magnetic field converter includes a hollow base and a convex ring on the base, the magnetic field converter is provided with a slit penetrating the base and the inside and outside of the convex ring, and the cross-section of the magnetic field converter is L-shaped; the method places the area to be formed of the plate above the base and outside the convex ring, utilizes the magnetic field generated by the induced eddy current on the convex ring of the magnetic field converter in the area to be formed of the plate to increase the radial electromagnetic force of the area to be formed of the plate, utilizes the magnetic field generated by the induced eddy current on the base of the magnetic field converter in the area to be formed of the plate to increase the axial electromagnetic force of the area to be formed of the plate, thereby improving the efficiency of plate flanging and increasing the angle of plate flanging.

[0007] The plate flanging method comprises the following steps:

[0008] Step 1: According to the sheet forming specification requirements, determine the height of the convex ring of the magnetic field converter, the outer diameter of the base of the magnetic field converter, and the angle between the slit and the center line of the magnetic field converter to make an L-shaped magnetic field converter;

[0009] Step 2: Use the edge clamp to fix the plate to be flanged, and place the magnetic field converter so that the forming area of ​​the plate to be flanged is located above the base of the magnetic field converter.

[0010] Step 3: Arrange the drive coil under the base of the magnetic field converter;

[0011] Step 4: Place the die above the flanged area of ​​the plate to be flanged and fix it;

[0012] Step 5: Connect the drive coil to the pulse power supply via the discharge switch.

[0013] Step 6: Control the discharge switch to supply power to the drive coil, generate induced eddy currents in the forming area of ​​the plate to be flanging, make the forming area of ​​the plate to be flanging move toward the die, and use the limiting effect of the die to complete the flanging of the plate.

[0014] Preferably, the angle between the slit of the magnetic field converter and the center line of the magnetic collector is 0.5°-1.5°.

[0015] Furthermore, the height of the convex ring of the magnetic field converter is greater than the length of the area to be formed of the plate.

[0016] Preferably, the outer diameter of the base of the magnetic field transformer is equal to the outer diameter of the driving coil.

[0017] The plate flanging device of the above-mentioned plate flanging method includes a driving coil, a magnetic field converter, a edge clamp, a die and a pulse power supply, wherein the driving coil is arranged below the base of the magnetic field converter, and the forming area of ​​the plate to be flanging is located above the base and outside the convex ring; the driving coil is connected to the pulse power supply via a discharge switch; the edge clamp is used to fix the edge clamping area of ​​the plate to be flanging; and the die is arranged above the edge clamping area of ​​the plate to be flanging.

[0018] The beneficial effects of the present invention include:

[0019] 1) Compared with the existing plate flanging method, the present invention greatly increases the flanging angle of the plate, which can reach a flanging angle of 90°;

[0020] By designing magnetic field converters with different base outer diameters and convex ring heights, different radial electromagnetic forces and axial electromagnetic forces are loaded in the flanging area of ​​the plate during the plate flanging process, thereby improving the flanging efficiency and forming quality of the plate.

[0021] 2) The magnetic field converter of the present invention is easy to produce, which reduces the difficulty of flanging the plate and is conducive to the production of flanging plates of various specifications;

[0022] 3) The present invention reduces the current peak value of the drive coil required for plate flanging, thereby extending the service life of the drive coil. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0024] Figure 1 FIG. 4 is a schematic diagram of an L-type magnetic field converter according to an embodiment of the present invention.

[0025] Figure 2 Schematic diagram of a plate flanging device according to an embodiment of the present invention.

[0026] Figure 3 FIG. 4 is a circuit diagram of a driving coil according to an embodiment of the present invention. DETAILED DESCRIPTION

[0027] Embodiment 1

[0028] like Figure 1 As shown, the L-shaped magnetic field converter includes a hollow base 2.2 and a convex ring 2.1 on the base. The magnetic field converter is provided with a slit 2.3 that penetrates the base and the inner and outer sides of the convex ring. The cross section of the magnetic field converter is L-shaped. The angle between the slit 2.3 and the center line of the magnetic collector is 1.5°. The height value of the convex ring of the magnetic field converter is h Greater than the length of the plate to be formed l The outer diameter of the base of the magnetic field transformer is equal to the outer diameter of the driving coil.

[0029] The embodiment utilizes the induced eddy currents on the convex ring 2.1 of the magnetic field converter to generate a magnetic field in the plate to be formed area 5.1, thereby increasing the radial electromagnetic force in the plate to be formed area, and utilizes the induced eddy currents on the base 2.2 of the magnetic field converter to generate a magnetic field in the plate to be formed area 5.1, thereby increasing the axial electromagnetic force in the plate to be formed area, thereby improving the efficiency of the plate flanging and increasing the angle of the plate flanging.

[0030] Embodiment 2

[0031] The second embodiment adopts the same L-shaped magnetic field converter as the first embodiment.

[0032] The plate flanging method of the embodiment comprises the following steps:

[0033] Step 1: According to the sheet forming specification requirements, determine the height of the convex ring of the magnetic field converter, the outer diameter of the base of the magnetic field converter, and the angle between the slit and the center line of the magnetic field converter to make an L-shaped magnetic field converter;

[0034] Step 2: Use the edge clamp to fix the plate to be flanged, and place the magnetic field converter so that the forming area of ​​the plate to be flanged is located above the base of the magnetic field converter.

[0035] Step 3: Arrange the drive coil under the base of the magnetic field converter;

[0036] Step 4: Place the die above the flanged area of ​​the plate to be flanged and fix it;

[0037] Step 5: Connect the drive coil to the pulse power supply via the discharge switch.

[0038] Step 6: Control the discharge switch to supply power to the drive coil, generate induced eddy currents in the L-shaped magnetic field converter and the forming area of ​​the plate to be flanging. Therefore, the electromagnetic force generated by the base of the L-shaped magnetic field converter is mainly axial; the electromagnetic force generated by the convex ring is mainly radial, so that the forming area of ​​the plate runs toward the direction of the die, and the flanging of the plate is completed by utilizing the limiting effect of the die.

[0039] The flanging device of the plate flanging method comprises a driving coil 1, a magnetic field converter 2, a flange holder 3, a die 4 and a pulse power supply. Figure 2 The driving coil 1 is arranged below the base 2.2 of the magnetic field converter, and the forming area 5.1 of the plate 5 to be flanged is located above the base 2.2 and outside the convex ring 2.1; the driving coil 1 is connected to the pulse power supply via the discharge switch, as shown in FIG. Figure 3 As shown; the edge holder 3 is used to fix the edge holding area 5.2 of the plate to be flanging; the die 4 is arranged above the edge holding area 5.2 of the plate 5 to be flanging.

Claims

1. A plate flanging method using an L-shaped magnetic field converter, characterized in that: The magnetic field converter comprises a hollow base and a convex ring on the base, the magnetic field converter is provided with a slit penetrating the base and the inner and outer sides of the convex ring, and the cross section of the magnetic field converter is L-shaped; the method places the to-be-formed area of ​​the plate above the base and outside the convex ring, and uses the magnetic field generated by the induced eddy current on the convex ring of the magnetic field converter in the to-be-formed area of ​​the plate to increase the radial electromagnetic force of the to-be-formed area of ​​the plate, and uses the magnetic field generated by the induced eddy current on the base of the magnetic field converter in the to-be-formed area of ​​the plate to increase the axial electromagnetic force of the to-be-formed area of ​​the plate, thereby improving the efficiency of the plate flanging and increasing the angle of the plate flanging; The method comprises the following steps: Step 1: According to the sheet metal forming specification requirements, determine the height of the convex ring of the magnetic field converter and the outer diameter of the base of the magnetic field converter to make an L-shaped magnetic field converter; Step 2: fix the plate to be flanged by using a flange holder, and place the magnetic field converter so that the forming area of ​​the plate to be flanged is located above the base of the magnetic field converter and outside the convex ring; Step 3: Arrange the drive coil under the base of the magnetic field converter; Step 4: Place the die above the flanged area of ​​the plate to be flanged and fix it; Step 5: Connect the driving coil to the pulse power supply via the discharge switch; Step 6: Control the discharge switch to power the drive coil, generate induced eddy currents in the forming area of ​​the plate to be flanging, make the forming area of ​​the plate run toward the die, and complete the flanging of the plate.

2. The plate flanging method according to claim 1, characterized in that: The angle of the slits of the magnetic field transformer is 0.5°-1.5°.

3. The plate flanging method according to claim 1, characterized in that: Height of the convex ring of the magnetic field converter h Greater than the length of the plate to be formed l .

4. The plate flanging method according to claim 1, characterized in that: The outer diameter of the base of the magnetic field transformer is equal to the outer diameter of the driving coil.

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