JP2007253182A - Electromagnetic forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electromagnetic forming apparatus which can provide increased productivity while avoiding flowing of large current through a drive circuit for inductors including a capacitor. <P>SOLUTION: A plurality of inductors 21(1)-21(n) (n is a natural number.) are respectively connected between electric discharge terminals 25(1)-25(n) and a grounding terminal 250. The capacitor 24 is charged with a proper power unit and one terminal of the capacitor 24 is respectively connected to the discharge terminals 25(1)-25(n) through a plurality of switches 22(1)-22(n). On and off of the switches 22(1)-22(n) is performed by being turned on by the supply of a low-current and low voltage trigger current and the trigger current is supplied from a proper trigger power source through trigger changeover switch 23. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electromagnetic forming apparatus for electromagnetically forming a plurality of materials.

  An electromagnetic forming technique for plastic processing of metal using electromagnetic force can flexibly cope with various shapes such as a plate shape or a tubular shape, and therefore, application to various fields is being studied. This electromagnetic forming technology instantaneously discharges the electric charge stored at a high voltage to the coil for electromagnetic forming, forms a strong magnetic field in a very short time around it, and places the workpiece in this magnetic field Thus, repulsive force is generated between the workpiece and the forming coil to perform forming. FIG. 11 is a conceptual diagram showing this electromagnetic forming technique. When the metal tube is expanded by electromagnetic forming, the shaft portion of the electromagnetic tube forming coil 16 around which the conductive wire is wound is inserted into the metal tube 14 which is a workpiece, and these are inserted into a predetermined position of the forming die 15. To place. Then, a large impact current is caused to flow from the wirings 17 a and 17 b to the conducting wire of the electromagnetic tube forming coil 16 to generate a magnetic field around the shaft portion of the electromagnetic tube forming coil 16. As a result, the metal tube 14 is expanded by receiving a strong expansion force due to the repulsive force of the magnetic field, and is pressed against the inner surface of the forming die 15, so that the metal tube 14 is formed by the forming die 15.

  This electromagnetic forming technology is suitable for forming aluminum and aluminum alloys and copper and copper alloys, which are good electrical conductors, and is currently used for forming grooves in aluminum alloy tubes and joining aluminum alloy tubes together. . Further, the application of electromagnetic forming is also being studied for processing of a large amount of deformation, such as bending of an end portion of an aluminum alloy tube or caulking of a large diameter tube, processing of a high-strength material, and the like. Furthermore, application to the processing of frame materials or parts such as vehicles, automobiles, and motorcycles is also being studied. And in patent document 1, the example of the tubular member with a flange material using pipe expansion molding is described. Further, Patent Document 2 is known as a technique for forming a plate-shaped metal material into a dish shape using a plate-shaped inductor.

JP 2003-393013 A JP 2001-526963 A

  However, the above example is basically a single-product production apparatus that uses a single capacitor and switch for a single inductor. FIG. 12A is a circuit diagram showing a drive circuit of this single-unit production electromagnetic forming apparatus. One terminal of the inductor 1 for molding is connected to the charging unit 4 through two discharge switches 2 and a charge switch 3. A capacitor 5 is connected between a connection point between the discharge switch 2 and the charge switch 3 and the other terminal of the inductor 1. In this electromagnetic forming apparatus, the discharge switch 2 is turned off and the charge switch 3 is turned on, and a current is supplied from the charging unit 4 to charge the capacitor 5. Thereafter, after the charge switch 3 is turned off, the discharge switch 2 is turned on to allow the charge accumulated in the capacitor 5 to flow through the inductor 1, and a large current is shockedly supplied to the inductor 1.

  However, in single-product production, productivity is low, and in order to reduce production costs, it is necessary to mass-produce with a multi-product production apparatus that simultaneously molds a plurality of materials. For this reason, as shown in FIG. 12B, it is necessary to connect the inductors 1a, 1b, 1c, and 1d in parallel and to electromagnetically form a plurality of materials simultaneously using the plurality of inductors 1a and the like. is there. However, as shown in FIG. 12B, in order to supply a large current to the plurality of inductors 1a, 1b, 1c, and 1d at the same time, it is necessary to use a capacitor having a large capacity. In addition, if the capacity of the capacitor is increased, a higher voltage and large current circuit is obtained, and the conductors, capacitors, and switches constituting the circuit require dedicated products that can withstand the high voltage and large current. In addition, by repeatedly energizing a large current for a short time, the consumption of components becomes severe.

  Further, when a large current is applied, the inductor generates heat and accumulates the generated heat. Therefore, even during mass production, a certain interval of energization is necessary, and productivity is deteriorated. On the other hand, as shown in FIG. 12 (c), a switch 6 is provided for alternately switching energization currents to the inductors 1a, 1b, 1c, and 1d. An electromagnetic forming apparatus is also conceivable in which the energization current is required for one inductor and charging of the capacitor 5 and energization of each inductor from the capacitor 5 are repeated alternately. However, in this electromagnetic forming apparatus, a current loss due to resistance occurs at the switching contact point through which a large current flows, and further, the wiring of the terminal portion moves or deforms due to the electromagnetic force action when a large current is applied. Furthermore, the circuit wiring that returns to the capacitor through the capacitor, the discharge switch, and the inductor when discharging from the capacitor also becomes a circuit resistance and generates a current loss.

  In the discharge switch 2 and the charge switch 3 as well, it is preferable that the standby time from the discharge to the recharge is long, and it is necessary to take a constant discharge interval even during mass production. For this reason, in the apparatus shown in FIG.12 (c), productivity is not fully improved.

  The present invention has been made in view of such problems, and an object thereof is to provide an electromagnetic forming apparatus capable of increasing productivity while avoiding an increase in current of an inductor drive circuit including a capacitor. To do.

  An electromagnetic forming apparatus according to the present invention includes a plurality of inductors for forming a plurality of materials, a capacitor that supplies current to these inductors, and a plurality that switches on / off of current supply from the capacitors to the inductor. A plurality of discharge switches; a charging unit for charging the capacitor; and a control unit that selectively drives the inductor by switching on and off the plurality of discharge switches.

  Another electromagnetic forming apparatus according to the present invention includes a plurality of collective inductors composed of one or a plurality of inductors for forming a plurality of materials, and is connected to each of the collective inductors to supply current to the inductors. A plurality of bank units, and a charging unit, wherein each bank unit includes a capacitor charged by the charging unit, a discharge terminal connected to the collective inductor and supplying a current to the collective inductor, A discharge switch that is connected between a capacitor and the discharge terminal and switches on / off of current supply to the discharge terminal, and further switches the on / off of the discharge switch to selectively drive the collective inductor. It has a control part.

  In the electromagnetic forming apparatus, for example, the collective inductor is a plurality of inductors connected in series, or a plurality of inductors connected in parallel.

  Still another electromagnetic forming apparatus according to the present invention includes a plurality of collective inductors including one or a plurality of inductors for forming a plurality of materials, and a plurality of collective inductors connected to each of the plurality of collective inductors. And each of the bank units is connected to a capacitor charged by the charging unit and the plurality of collective inductors to supply current to the collective inductor. A plurality of discharge terminals, a plurality of discharge switches connected between the capacitor and the plurality of discharge terminals for switching on / off of current supply to the discharge terminals, and selectively turning on / off the discharge switches And a control unit for selectively driving the collective inductor by controlling the changeover switch. The features.

  In this electromagnetic forming apparatus, for example, the plurality of collective inductors connected to each bank unit is a plurality of inductors connected in series, or a plurality of inductors are connected in parallel, respectively. It has been done.

  According to the present invention, it is possible to electromagnetically form a plurality of materials at the same time while avoiding an increase in current of an inductor drive circuit including a capacitor, and it is possible to improve productivity by mass production effect.

  Hereinafter, embodiments of the present invention will be specifically described with reference to the accompanying drawings. FIG. 1 is a diagram showing a circuit portion of an electromagnetic forming apparatus according to a first embodiment of the present invention. A plurality (n: n is a natural number) of inductors 211 to 21n are connected between the discharge terminals 251 to 25n and the ground terminal 250 of the capacitor bank power supply 20, respectively. In the capacitor bank power supply 20, the capacitor 24 is charged by an appropriate power supply device, and one terminal of the capacitor 24 is connected to the discharge terminals 251 to 25n via a plurality of switches 221 to 22n, respectively. ing. The switches 221 to 22n are turned on when the trigger voltage is supplied, and the trigger voltage is supplied from the appropriate trigger voltage via the trigger changeover switch 23.

  In the electromagnetic forming apparatus of the present embodiment configured as described above, a charge corresponding to a current supplied to one inductor is accumulated in the capacitor 24. Thereafter, the trigger switch 23 is switched to the switch 221 and the trigger voltage is supplied to the switch 221. As a result, the switch 221 is turned on, a large molding current is supplied from the capacitor 24 to the molded inductor 211, and the material is electromagnetically molded by the inductor 211.

  Next, the switch 23 is disabled (not connected to any of the switches 221 to 22n), and the capacitor 24 is charged. Thereafter, the trigger changeover switch 23 is connected to the next switch (not shown), this switch is turned on to discharge the capacitor 24, and a large current for molding is supplied to the next inductor (not shown). Next, the trigger changeover switch 23 is disabled, the capacitor 24 is charged, the next switch is turned on, and the discharge current is supplied to the next inductor. This operation is repeated, and finally, after charging the capacitor 24, the trigger voltage is supplied to the switch 22n, and the discharge current is supplied to the inductor 21n via the switch 22n.

  In the present embodiment, since the current switched by the trigger changeover switch 23 is a low voltage and low current trigger voltage, there is no need to switch the large current conducting portion. Therefore, there is no current loss and terminal portion consumption due to large current switching.

  FIG. 2 is a diagram showing a circuit portion of an electromagnetic forming apparatus according to the second embodiment of the present invention. Bank units 321 to 32n are connected to a plurality (n) of inductor units 311 to 31n, respectively. In each bank unit 321-32n, a switch 32 and a capacitor 34 are provided, a charging terminal of the charging unit 33 is connected to the capacitor 34, and the capacitor 34 is charged by the charging unit 33. ing. The switch 32 is connected between the charge terminal of the capacitor 34 and the discharge terminals of the units 321 to 32n, and the ground terminal of the capacitor 34 is connected to the ground terminals of the units 321 to 32n. In the inductor units 311 to 31n, for example, three molding inductors 31 are connected in series, and three materials can be molded simultaneously in one unit.

  In the electromagnetic forming apparatus configured as described above, the capacitor 34 is charged by supplying current from the charging unit 33 to the capacitors 34 of all the bank units 321 to 32n. Then, the trigger voltage is supplied to the switch 32 to turn on the switch 32. As a result, the discharge current of the capacitor 34 is supplied to the three inductors 31 connected in series of the collective inductor 311.

  In the present embodiment, by charging one capacitor 34, a large current can be supplied to the three inductors 31 at a time to form three materials electromagnetically. Therefore, 3n materials can be simultaneously formed using n bank units 321 to 32n. In the present embodiment, it is necessary that the capacity of the capacitor that can supply power to the three inductors 31 is a large capacity, but since the on / off of the switch is switched by a trigger voltage of a low voltage and a low current. There is no inconvenience when switching a large current as in FIG. Moreover, since the circuit which returns a charging part to a capacitor | condenser through a capacitor | condenser, a discharge switch, an inductor is provided as another unit, the circuit wiring of the units 321-32n can be integrated short, and the current loss by circuit resistance can be reduced.

  Moreover, in this embodiment, since it is divided into n units 321-32n, the capacitor capacity only needs to flow an impact current through three inductors. Further, as compared with the case where 3n inductors are connected in series (conventional FIG. 12C), a relatively low current and low voltage can be achieved in each unit. For this reason, it is possible to use conductors, capacitors, and switches constituting the circuit with a low voltage and small current specification. In addition, the cost of the entire apparatus can be reduced by sharing the charging unit for each bank unit. Furthermore, a control unit for driving the switch 32 of each bank unit is provided, and by performing differential energization in which molding in each unit is sequentially performed at a constant time interval, the inductor cooling period can be taken. The life of each component can be extended. Furthermore, since there is no large current switching part, the switching contact can be eliminated, and there is no current loss and no terminal wear.

  FIG. 3 is a circuit diagram showing the voltage reduction effect when three inductors 31 are connected in series to each of the collective inductors 311 to 31n in the embodiment shown in FIG. As in the present embodiment, in one collective inductor, since three inductors 31 are connected in series, the same current flows in common to all the inductors 31 provided in one unit. All the inductors 31 in the unit can generate the same electromagnetic force. For this reason, the deformation amount of the material to be molded / joined is less varied and uniform molding can be performed. Furthermore, if the voltage of V is necessary for one unit by connecting in series, in the case of N units, not only N × V but a voltage of V√N lower than that is sufficient. Each component in the unit can be a component using a lower voltage and a smaller current.

As shown in FIG. 3, when there is one molding inductor 31, when the capacitor 34 is 200 μF and the charging voltage is 5 kV, the energy that can be supplied to the inductor 31 is P = (1/2) CV ² = 2. 5 (kJ).

  On the other hand, when three forming inductors 31 are connected in series, 7.5 kJ of energy is required in total to supply 2.5 kJ of energy to each inductor 31. Is 200 μF, the charging voltage V is V = √ ((2 × P) / C) = 8.66V. That is, the required voltage per inductor is not 8. 5 kV × 3 = 15 kV, but 8.66 kV, and a power supply device for lower voltage and small current can be used. The number of inductors in the collective inductor is not limited to three and is arbitrary.

  FIG. 4 is a diagram showing a circuit portion of the electromagnetic forming apparatus according to the third embodiment of the present invention. In the present embodiment, three inductors 31 in the collective inductors 311 to 31n are connected in parallel. When the inductor 31 is connected in parallel, the amount of current that flows between the inductor close to the capacitor and the inductor far from the capacitor in the distance of the conducting wire is different, so that there is a difference in forming ability. Using this effect, it is possible to form different shapes in the unit. In FIG. 2 or FIG. 4, the collective inductors in all the units are connected in series or in parallel, but a series collective inductor and a parallel collective inductor may be mixed.

  FIG. 5 is a diagram showing a circuit portion of an electromagnetic forming apparatus according to the fourth embodiment of the present invention. In the bank unit 321, for example, four switches 3211 to 3214 are connected in parallel, and the switches 3211 to 3214 to which a trigger voltage is to be supplied are switched by the trigger changeover switch 35. Collective inductors 3111 to 3114 are connected to the four changeover switches 3211 to 3214 of the bank unit 321, respectively. In these collective inductors 3111 to 3114, for example, three inductors 31 are connected in series.

  In the present embodiment, the trigger changeover switch 35 sequentially supplies trigger voltages to the switches 3211 to 321n to turn them on. For example, four units in which three inductors 31 are connected in series are sequentially supplied at regular time intervals. Perform differential energization. Thereby, it is possible to electromagnetically form 3 × 4 × n inductors. In addition, the cooling period of the inductor can be taken, and the life of each component can be extended. Furthermore, since there is no large current switching part, the switching contact can be eliminated, and there is no current loss and no terminal wear.

  FIG. 6 shows a system diagram of the controller of the present invention. Since charging / discharging to each bank unit is collectively controlled by the control panel, differential energization as shown below is possible. An example of this differential energization procedure is shown in Table 1 below. Although not described here, differential energization between bank units is also possible.

Table 1

  FIG. 7 is a diagram showing the relationship between the circuit portion and the control portion of the electromagnetic forming apparatus according to the fifth embodiment of the present invention. In the bank units 1 to n, for example, four collective inductors connected to three inductors are connected in parallel, and a discharge switch DW is connected to each of these collective inductors. Furthermore, since all the discharge switches and the charge switches are connected so as to be controlled by commands from the external control unit, the switches in each bank unit or the switches between each bank unit are charged in an arbitrary order at an operation interval. Energization can be repeated.

  FIG. 8 is a diagram showing a circuit portion of an electromagnetic forming apparatus according to the sixth embodiment of the present invention. In the present embodiment, four collective inductors 3111 to 3114 and 31n1 to 31n4 are connected to n bank units 321 to 32n, respectively. The present embodiment is different from the fourth embodiment shown in FIG. 5 in that each of the collective inductors 3111 to 3114 and 31n1 to 31n4 has three inductors 31 connected in parallel. This embodiment also has the same effect as the embodiment shown in FIG.

  FIG. 9 is a diagram showing a circuit portion of an electromagnetic forming apparatus according to the seventh embodiment of the present invention. In the present embodiment, four collective inductors 3111 to 3114 and 31n1 to 31n4 are connected to n bank units 321 to 32n, respectively. This embodiment differs from the fourth embodiment shown in FIG. 5 in that some of the collective inductors 3111 to 3114 and the like are obtained by connecting three inductors 31 in parallel, and the remaining collective inductors 31n1 to 31n1. 31n4, etc. is that three inductors 31 are connected in series. That is, the collective inductor is a combination of a parallel connection body of inductors and a serial connection body. This embodiment also has the same effect as the embodiment shown in FIG.

  FIG. 10 is a diagram showing a circuit portion of an electromagnetic forming apparatus according to the eighth embodiment of the present invention. A plurality of discharge switches 61 and 62 are connected in parallel between a series connection body of inductors 60 or an inductor unit and the capacitor 63.

  In the present embodiment, when the switch standby time is longer than the time required for charging the capacitor 63, the plurality of discharge switches 61 and 62 are connected in parallel in this way, and used in order, thereby waiting. The electromagnetic molded body can be mass-produced while keeping time.

  In addition, the discharge switch used for this invention can use various switches, such as a gap switch, a thyratron switch, a semiconductor switch, and an ignitron switch, as a high-speed, high-voltage, high-current starting switch. Although an example of one switch is shown in this figure, a plurality of switches may be connected in parallel in order to suppress switch wear.

  The present invention can realize cost reduction in processing and joining using electromagnetic forming of other metals or alloys such as automobile materials, container materials such as aluminum and aluminum alloys, and copper and copper alloys.

It is a figure which shows the circuit part of the electromagnetic forming apparatus which concerns on 1st Embodiment of this invention. It is a figure which shows the circuit part of the electromagnetic forming apparatus which concerns on 2nd Embodiment of this invention. In this 2nd Embodiment, it is a conceptual diagram which shows the voltage reduction effect of three inductors connected in series of the collective inductor. It is a figure which shows the circuit part of the electromagnetic forming apparatus which concerns on 3rd Embodiment of this invention. It is a figure which shows the circuit part of the electromagnetic shaping | molding apparatus which concerns on 4th Embodiment of this invention. It is a system system | strain diagram of the control part of this invention. It is a figure which shows the relationship between the circuit part and control part of the electromagnetic forming apparatus which concerns on 5th Embodiment of this invention. It is a figure which shows the circuit part of the electromagnetic forming apparatus which concerns on 6th Embodiment of this invention. It is a figure which shows the circuit part of the electromagnetic forming apparatus which concerns on 7th Embodiment of this invention. It is a figure which shows the circuit part of the electromagnetic shaping apparatus which concerns on 8th Embodiment of this invention. It is a schematic diagram which shows an electromagnetic forming technique. (A) thru | or (c) is a figure which shows the conventional electromagnetic forming apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1a, 1b, 1c, 1d: Inductor 2: Discharge switch 3: Charge switch 6: Changeover switch 4: Charging part 5: Capacitor 14: Metal pipe 15: Mold 16: Coil 17a, 17b: Wiring 20: Power supply 211 21n: Inductors 221-2n: Switch 23: Switch 23: Trigger switch 24, 34: Capacitor 250: Ground terminal 251-25n: Discharge terminal 31: Inductor 3111-3114, 31n1-31n4: Collective inductor 32, 3211-3214: Discharge switch 321-32n: Bank unit 33: Charging unit 34: Capacitor 35: Trigger switch 60: Inductor 61, 62: Discharge switch 63: Capacitor 64: Charge switch

Claims (7)

A plurality of inductors for forming a plurality of materials, a capacitor for supplying current to the inductors, a plurality of discharge switches for switching on and off the supply of current from the capacitors to the inductor, and the capacitor An electromagnetic forming apparatus comprising: a charging unit for charging; and a control unit that selectively drives the inductor by switching on and off the plurality of discharge switches. A plurality of collective inductors composed of one or a plurality of inductors for forming a plurality of materials, a plurality of bank units connected to each of the collective inductors to supply current to the inductors, a charging unit, And each bank unit is connected between the capacitor and the discharge terminal, a capacitor charged by the charging unit, a discharge terminal to which the collective inductor is connected and supplies current to the collective inductor. A discharge switch that switches on and off the supply of current to the discharge terminal, and further includes a controller that selectively drives the collective inductor by switching on and off the discharge switch. apparatus. The electromagnetic forming apparatus according to claim 2, wherein the collective inductor is a plurality of inductors connected in series. The electromagnetic forming apparatus according to claim 2, wherein the collective inductor is a plurality of inductors connected in parallel. A plurality of collective inductors comprising one or a plurality of inductors for forming a plurality of materials, a plurality of bank units connected to each of the plurality of collective inductors and supplying current to the inductors, and a charging unit And each bank unit includes a capacitor charged by the charging unit, a plurality of discharge terminals connected to the plurality of collective inductors to supply current to the collective inductor, the capacitors, and the A plurality of discharge switches connected between a plurality of discharge terminals and switching on / off of current supply to the discharge terminals; and a selector switch for selectively switching on / off of the discharge switches; An electromagnetic forming apparatus comprising: a control unit that controls the changeover switch to selectively drive the collective inductor. 6. The electromagnetic forming apparatus according to claim 5, wherein the plurality of collective inductors connected to each bank unit are a plurality of inductors connected in series. 6. The electromagnetic forming apparatus according to claim 5, wherein each of the plurality of collective inductors connected to each bank unit is a plurality of inductors connected in parallel.

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