JP2005279760A - Control method of charged particle flow, and control method of molten metal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a novel and useful arc control method. <P>SOLUTION: Electric wires 4 (current paths) through which a current flows in a direction nearly parallel to the flowing direction of a welding arc are formed. A magnetic field generated around the electric wires 4 when they are energized is made to act on electrons in the welding arc to generate the Lorentz's force, thereby controlling the welding arc by the Lorentz's force. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for controlling a flow of charged particles such as an arc, plasma, and electron beam, a method for controlling a welding arc and plasma, and a method for controlling a molten metal such as a molten metal pool formed by the welding arc.

  Arc welding is a type of fusion welding in which a welding arc is generated and the members to be welded are melted by the arc heat of the welding arc, and the electrode is melted, such as MAG welding or MIG welding. And non-melting type electrodes such as TIG welding in which the electrodes do not melt.

  Various techniques relating to the control of arc, molten metal pool, and weld bead in arc welding have been proposed as described below.

  Patent Document 1 describes a technique for displacing a molten metal pool or a molten bead generated by welding arc or welding with an external force. According to this, when welding the vertical joint portion near the interface between the bottom plate and the side plate, the welding torch is tilted downward by 10 to 45 °, is substantially perpendicular to the welding line and the arc direction, and the arc is upward. A technique has been proposed in which the direction of the arc is controlled so that the direction of the arc is upward by generating a DC magnetic field that generates the Lorentz force, thereby preventing the molten metal from dripping.

  Patent Document 2 proposes a technique for generating a magnetic field parallel to the arc and converging the arc by Lorentz force.

Patent Document 3 proposes a technique for performing welding while applying a magnetic field so that the metal solidified portion is lifted in the narrow groove lateral welding.
Patent No. 2912150 Japanese Patent Publication No. 07-102458 Japanese Patent Publication No. 07-73791

  An object of the present invention is to provide a novel and useful method for controlling arc and molten metal in arc welding.

  The method of the present invention is not limited to welding arc control or molten metal control, but can be applied to other charged particle flows other than welding. Therefore, the present invention also aims to provide a novel charged particle flow control method.

The invention of claim 1 made to solve the above technical problem is:
A current path through which a current flows in a direction substantially parallel to the flow direction of the charged particle flow is formed, and a magnetic field generated around the current path when the current path is energized is applied to the charged particles in the charged particle flow. A charged particle flow control method is characterized in that a Lorentz force is generated by acting, and the charged particle flow is controlled by the generated Lorentz force.

The invention of claim 2 is the invention of claim 1,
A plurality of the current paths are formed so as to surround a periphery of the flow of the charged particle flow, and a direct current is supplied to the plurality of current paths in the same direction and simultaneously.

The invention of claim 3 is the invention of claim 1,
A plurality of the current paths are formed so as to surround a periphery of the flow of the charged particle flow, and a direct current is sequentially supplied to the plurality of current paths in the same direction.

The invention of claim 4 is the invention of claim 1,
It is characterized in that at least two current paths are formed on both sides of the flow of the charged particle flow, and a direct current flows in the same direction through the two current paths.

The invention of claim 5 is the invention of claim 1,
At least one of the current paths is formed on one side of the flow of the charged particle flow, and an alternating current is passed through the current path.

The invention of claim 6 is the invention of any one of claims 1 to 5,
The charged particle flow is a welding arc or plasma.

Further, the invention of claim 7 made to solve the above technical problem,
A magnetic field generated around the current path when a current path is formed in which the current flows in a direction substantially parallel to the flow direction of the current passing through the molten metal formed by arc welding. It is a method for controlling a molten metal, characterized in that a Lorentz force is generated by acting on charged particles in the molten metal, and the molten metal is controlled by the generated Lorentz force.

The invention of claim 8 is the invention of claim 7,
Forming at least two current paths on both sides of the current flow passing through the molten metal, the current flowing in the two current paths in the same direction and opposite to the current flow direction passing through the molten metal; It is characterized by flowing.

  According to the first aspect of the present invention, the current path (electric wire) is formed in a direction substantially parallel to the flow direction of the charged particle flow such as a welding arc, and the current is passed through the current path. Then, a magnetic field is generated around the current path. Since the direction of the generated magnetic field is parallel to a plane perpendicular to the flow direction of the charged particle flow, it acts on the charged particles in the charged particle flow in the vertical direction. Accordingly, the charged particles in the charged particle flow are subjected to Lorentz force, and the flow of the charged particle flow is changed by the Lorentz force. Thereby, the flow of the charged particle flow can be controlled.

  The charged particle flow is a flow of charged particles, and is a concept of a flow including an electric current (electron flow), an ion flow (ion flow), plasma, and the like. Further, the charged particle flow applied to the present invention is not particularly limited, and forms a flow of charged particles such as an arc, plasma, electron flow (electron beam), ion flow (ion beam), etc. If it is good.

  The control of the charged particle flow is to apply an operation to the density (strength) and the flow direction in order to bring the charged particle flow into a target state.

  A feature of the present invention is that a current flows in a direction substantially parallel to the flow of the charged particle flow. By flowing in this manner, the charged particle flow can be easily controlled, and various charged particle flow controls can be realized by devising a current flow method.

  According to the second aspect of the present invention, a plurality of current paths are provided so as to surround the periphery of the flow of the charged particle flow, a direct current is supplied to the current path in the same direction, and the flow direction of the charged particle flow is Simultaneously flow in substantially parallel directions. When a direct current is passed in this way, a magnetic field is generated around each current path, but the combined magnetic field of each magnetic field becomes a rotating magnetic field that rotates around the charged particle flow. When such a rotating magnetic field acts on the charged particles in the charged particle flow, the charged particles are drawn in the center of the charged particle flow in a plane perpendicular to the flow of the charged particle flow or in the charged particle flow. A Lorentz force is applied in a direction radially away from the center. When receiving a Lorentz force in the direction of being drawn into the center of the charged particle flow, the charged particle irradiation cross-sectional area in a plane perpendicular to the flow of the charged particle flow is reduced and the flow is converged. For this reason, the energy density of the charged particle flow can be increased. On the other hand, when a Lorentz force is received in a direction radially away from the center of the charged particle flow, an irradiation cross-sectional area of the charged particles in a plane perpendicular to the charged particle flow becomes large and the flow is diffused. For this reason, the charged particle flow can be irradiated over a wide range. That is, the convergence state or diffusion state of the charged particle flow can be controlled by the method of the present invention.

  For example, when the charged particle flow is a flow by arc discharge and the direction of this arc discharge is regarded as an arc current (flow from the positive electrode to the negative electrode), a plurality of direct currents surrounding the arc current When the direction of the current is flowing in the direction opposite to the arc current, the electrons in the arc receive a Lorentz force in the direction toward the center of the arc, and as a result, the arc converges to increase its energy density. . Further, when the current flows in the same direction as the arc current, electrons in the arc receive a Lorentz force in a direction away from the center of the arc, and as a result, the arc can diffuse and irradiate the arc over a wide range.

  The “same direction” indicates that all of the plurality of direct currents flow in the same direction.

  Further, according to the invention of claim 3, a plurality of current paths are provided so as to surround the periphery of the flow of the charged particle flow, a direct current is provided in these current paths in the same direction, and substantially the same as the flow direction of the charged particle flow. Sequentially flow in parallel directions. When a direct current is passed sequentially in this way, the direction of action of the Lorentz force generated based on the magnetic field generated around the direct current changes sequentially. For this reason, the direction in which the charged particle flow is affected by the Lorentz force also changes, and as a result, the charged particle flow can be rotated. That is, according to the present invention, the charged particle flow can be rotationally controlled.

  In the above description, “sequentially” means “following current paths in order”, and includes sequentially stopping energization after sequentially energizing.

  According to the fourth aspect of the present invention, at least two current paths are provided on both sides of the flow of the charged particle flow, and a direct current is passed through these current paths in the same direction. By flowing an electric current in this way, Lorentz force can act on electrons in the charged particle flow from a specific direction, and as a result, the cross-sectional area in the flow direction of the charged particle flow can be extended or compressed in one direction. Can do. In the present invention, a direct current may be supplied simultaneously to the two current paths or may be controlled so as to be supplied alternately.

  According to the invention of claim 5, at least one current path is provided on one side of the flow of the charged particle flow, and an alternating current is passed through the current path. By flowing an alternating current in this way, the direction of the Lorentz force received by the electrons in the charged particles can be sequentially reversed, and as a result, it can be extended in one direction to the cross-sectional area in the flow direction of the charged particle flow. Can do.

  In the present specification, the “alternating current” refers to a waveform that draws a sine waveform with a current value generally called an alternating current centered at 0, and other waveforms that are not sine waveforms, such as a rectangular wave. But what is presented is also included.

  According to the sixth aspect of the invention, since the Lorentz force is applied to the welding arc or plasma as the charged particle flow, the shape and strength of the welding arc or plasma can be controlled widely.

  According to the invention of claim 7, a current path (electric wire) is formed in a direction substantially parallel to the flow direction of the current passing through the molten metal formed by arc welding, and the current path Apply current. Then, a magnetic field is generated around the current path. Since the direction of the generated magnetic field is parallel to a plane perpendicular to the flow direction of the current passing through the molten metal, electrons in the molten metal receive Lorentz force, and the flow of the molten metal is caused by this Lorentz force. Change. Thereby, the flow of the molten metal can be controlled.

  According to the invention of claim 8, at least two current paths are formed on both sides of the current flow passing through the molten metal, and the current passes through the two current paths in the same direction and through the molten metal. The current flows in the opposite direction to the current flow direction. By passing an electric current in this way, electrons in the molten metal receive a Lorentz force in a direction toward the center of the molten metal. For this reason, the molten metal causes convection from the edge side toward the center. As a result, the opportunity for the molten metal to come into contact with the base material on the bottom surface increases, and the penetration depth can be further increased.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments according to the present invention will be described below with reference to the drawings.

(First embodiment)
FIG. 1 is a schematic view showing a welding arc control method according to the first embodiment of the present invention. In this example, an example of TIG welding is illustrated, and as shown in the figure, the welding torch 1 is arranged so that the tip of an electrode rod 1a including a tungsten electrode faces downward. In addition, an object A to be welded is disposed below the welding torch 1 with a predetermined spatial distance. The welding torch 1 and the member to be welded A are electrically connected by a welding power source 10. The welding power source 10 generates direct current or direct current pulse current.

  Around the welding torch 1 and the workpiece A, a magnetic field generator 2 is disposed. As shown in FIG. 1, the magnetic field generator 2 includes a DC power supply 3 and a plurality of electric wires 4 electrically connected to the DC power supply 3. The electric wires 4 are arranged in parallel so that a current flows in the vertical direction from the welding torch 1 side toward the welded member A side, and one end (upper end) of each electric wire 4 is connected to the positive electrode of the power source 3. The end (lower end) is connected to the negative electrode of the power source 3. Therefore, when each electric wire 4 is energized, current flows from the upper side to the lower side of each electric wire 4.

  FIG. 2 is a diagram showing the positional relationship between the electrode rod 1a of the welding torch 1 and the welding arc ARC generated from the electrode rod 1a and the electric wire 4 of the magnetic field generator 2, and these configurations are shown by the arrow A1 in FIG. It is seen from the upper side shown by. As shown in FIG. 2, each electric wire 4 is disposed so as to surround the entire circumference of the welding arc ARC generated from the electrode rod 1a. In order to dispose the electric wire 4 in this way, each electric wire is embedded in a cylindrical member formed of an insulator such as ceramics in the axial direction to produce an integrated body of the electric wire 4 and the ceramic cylindrical body. It is good also as an aspect which covers a welding torch 1 with a cylindrical body, and it is good also as an aspect which covers the welding torch 1 which formed the wire harness in the shape of a cylinder.

  In the above configuration, a welding arc is generated from the welding torch 1. Then, an arc discharge occurs in the vertical direction between the electrode rod 1a and the member A to be welded, and a welding arc ARC is generated. And the to-be-welded member A fuse | melts with the arc heat of the generated welding arc ARC, and welding is performed.

  Further, along with the generation of the welding arc ARC, the magnetic field generator 2 is operated to pass a current through each electric wire 4. In this case, the direction of the current in each electric wire 4 flows from the top to the bottom so as to be substantially parallel to the welding arc formation direction (vertical direction) as shown in FIG.

  When a current flows through the electric wire 4, a magnetic field is generated around it. As shown in FIG. 2, since the direction of the current flowing through the electric wire 4 is from the front side to the back side of the paper in FIG. 2, the direction of the generated magnetic field is indicated by the arrow A2 in FIG. Thus, the direction is clockwise. The magnetic field generated in this way is generated in each electric wire 4, and when these magnetic fields are combined, a magnetic field rotating counterclockwise around the welding torch 1 as shown by an arrow B in FIG. Become.

  In this example, TIG welding is performed. In the case of TIG welding, the electrode rod 1a side is a negative electrode, and the welded member A side is a positive electrode. Therefore, the generated arc current Iarc flows from the welded member A side to the electrode rod 1a side. That is, the arc current Iarc flows from the bottom to the top in FIG.

  The welding arc emitted from the electrode rod 1a tries to diffuse with a certain spread in the horizontal direction from the electrode rod 1a to the member A to be welded. In this case, for example, as shown in FIG. 2, when the influence of electrons from the magnetic field B at a position X1 shifted from the center of the electrode rod 1a by a predetermined distance in the right direction in the drawing is examined, the direction of the arc current Iarc at X1 is Since the direction of the magnetic field at X1 is the front direction from the back side of the page, and the upward direction indicated by the arrow B1 direction, the electromagnetic force F1 is directed toward the center of the electrode rod 1a according to the Fleming left-hand rule ( It occurs in the left direction in the figure. Further, considering the influence of electrons from the magnetic field B at the position X2 that is shifted from the center of the electrode rod 1a by a predetermined distance in the upper right direction in the figure, the direction of the current in X2 is the front side from the back side of the page, and X2 Since the direction of the magnetic field is the upper left direction indicated by the arrow B2, the electromagnetic force F2 is generated in the direction toward the center of the electrode rod 1a (the lower left direction in the drawing) according to the Fleming left hand rule. Similarly, the electromagnetic forces F3, F4, F5, and F6 at the positions X3, X4, X5, and X6 are also influenced by the magnetic fields B3, B4, B5, and B6 in the field, and are directed toward the center of the electrode rod 1a. Occurs.

  That is, the electromagnetic force acts in the direction toward the center of the arc ARC generated from the electrode rod 1a by the magnetic field B. As a result, the spread of the arc is suppressed, and the welded member A is irradiated with the arc converged as shown in FIG.

  Therefore, in the arc irradiation part in the member A to be welded, the energy density is increased by converging the arc, and as a result, deep penetration welding can be realized. Moreover, since the melting time can be reduced by increasing the energy density, high-speed welding is also possible.

  The above example is an example of converging the welding arc with the arc current and the direction of current flowing through each wire as opposite directions. However, if the arc current and the direction of current flowing through each wire are set in the same direction, convergence is achieved. Conversely, the welding arc can be spread over a wide area. By diffusing in this way, it is possible to weld a wide area. In this case, in addition to welding, it can also be expected as an alternative means of heat treatment such as surface modification of the base material.

(Second Embodiment)
FIG. 3 is a diagram showing a welding arc control method in the second embodiment of the present invention. In this example, the energization control to the electric wire of the magnetic field generator is different from that of the first embodiment, and other configurations are basically the same as those of the first embodiment.

  In the first embodiment, the welding arc is converged by simultaneously energizing the electric wires. In this example, the electric wires are energized sequentially. For example, the first electric wire 41 is first energized, and after a predetermined time (minute time) has elapsed, the energization of the first electric wire 41 is stopped and the second electric wire 42 adjacent to the first electric wire 41 is energized. Next, after the predetermined time (minute time) has elapsed, the energization of the second electric wire 42 is stopped and the third electric wire 43 adjacent to the second electric wire 42 is energized. In this way, the first electric wire 41, the second electric wire 42, the third electric wire 43, the fourth electric wire 44, the fifth electric wire 45, and the sixth electric wire 46 are sequentially energized, and this is repeated.

  The state of the welding arc when the electric wires are sequentially energized as described above while the welding arc is generated from the electrode rod 1a will be examined. First, in a state where the first electric wire 41 is energized, the direction of the arc current Iarc at the position X4 located on the opposite side of the first electric wire 41 with the electrode rod 1a interposed therebetween is the front side from the back side of the page. Further, since the direction of the magnetic field at the position X4 is the upper left direction shown in the arrow B4 direction, the electromagnetic force F4 is generated in the direction away from the first electric wire 41, that is, the lower left direction shown in the figure, according to the Fleming left-hand rule. Therefore, the welding arc in this case is formed in the region R4 in the drawing. When the second electric wire 42 is energized, the direction of the arc current Iarc at the position X5 located on the opposite side of the second electric wire 42 across the electrode rod 1a is the front side from the back side of the page. In addition, since the direction of the magnetic field at the position X5 is the upward direction shown in the direction of arrow B5, the electromagnetic force F5 is generated in the direction away from the second electric wire 42, that is, the left side in the figure, according to the Fleming left-hand rule. Therefore, the welding arc in this case is formed in the region R5 in the drawing. Similarly, in a state where the third electric wire 43, the fourth electric wire 44, the fifth electric wire 45, and the sixth electric wire 46 are energized, the electromagnetic forces F6, F1, F2, and F3 at the positions X6, X1, X2, and X3 are In this case, the welding arcs are formed in regions R6, R1, R2, and R3 in the respective directions.

  That is, the welding arc is deflected away from the energized wire. Therefore, by switching energization to the adjacent electric wires one after another, the deflection direction of the welding arc is sequentially shifted, and it is possible to realize a state where the welding arc is rotating.

  As a welding method, there is a welding method such as a rotary welding method in which a welding torch is rotated to perform a wide range of welding, but the method of this example can be an alternative method of this rotary welding method. In this case, there is no need to adopt a complicated structure such as a rotating mechanism of a welding torch, and rotational welding can be realized with an inexpensive configuration.

  FIG. 4 is a modification of this example. That is, in the above example, the electric current in each electric wire flows from the front side to the back side in FIG. 3, but in FIG. 4, it flows from the back side to the front side.

  In such energization control, when considering the electromagnetic force generated when a current flows through the first electric wire 41, the magnetic field acting on the electrons existing at the position X1 approaching the first electric wire 41 from the electrode rod 1a in the figure is: Acting in the lower right direction indicated by the arrow B1 in the figure, and the direction of the arc current Iarc flows from the back side to the near side in FIG. 4, the electromagnetic force is in the direction indicated by the arrow F1, that is, in the first direction. Acts in a direction approaching one electric wire 41. Therefore, the welding arc as a whole approaches the first electric wire 41 and is formed by being deflected to a region R1 in the drawing.

  Further, when considering the electromagnetic force generated when a current flows through the second electric wire 42, the magnetic field acting on the electrons existing at the position X2 approaching the second electric wire 42 from the electrode rod 1a in the figure is the direction of the arrow B2 shown in the figure. 4 and the direction of the arc current Iarc flows from the back side to the front side in FIG. 4, so that the electromagnetic force is in the direction indicated by the arrow F2, that is, the direction approaching the second electric wire 42. Act on. Accordingly, the welding arc as a whole approaches the second electric wire 42 and is formed by being deflected to a region R2 in the drawing.

  Similarly to the above, when a current is passed through the third electric wire 23 (the fourth electric wire 24, the fifth electric wire 25, the sixth electric wire 26), the welding arc as a whole is the third electric wire 23 (the fourth electric wire 24, It approaches the fifth electric wire 25 and the sixth electric wire 26) and is deflected and formed in the region R3 (R4, R5, R6) in the drawing.

  That is, the welding arc is deflected so as to approach the energized electric wire. Therefore, by switching energization to the adjacent electric wires one after another, the deflection direction of the welding arc is sequentially shifted, and it is possible to realize a state where the welding arc is rotating.

  FIG. 5 shows another modification. That is, in this example, as shown in FIG. 5, the directions of the currents flowing through the wires opposed to each other with the electrode rod 1a interposed therebetween are opposite to each other. In addition, when energizing, the current is sequentially passed through the adjacent wires as in the above example, and the opposing wires are simultaneously energized. That is, in FIG. 5, first, a current is simultaneously supplied to the first electric wire 41 and the fourth electric wire 44 disposed opposite to the first electric wire 41 with the welding torch (electrode bar 1a) interposed therebetween, and a predetermined time (minute time). After the elapse of time, the energization to the first electric wire 41 and the fourth electric wire 44 is stopped, and the second electric wire 42 adjacent to the first electric wire 41 and the fifth electric wire arranged opposite to the second electric wire 42 with the welding torch interposed therebetween. Energize 45. Further, after a predetermined time (smile time) has elapsed, the energization of the second electric wire 42 and the fifth electric wire 45 is stopped, and the third electric wire 43 adjacent to the second electric wire 42 and the third electric wire are sandwiched between the welding torch. The sixth electric wire 46 arranged opposite to the current 43 is energized. In this way, the opposing wires are energized simultaneously, and the adjacent wires are energized sequentially.

  In this energization control, when the electromagnetic force generated when the current I1 is passed through the first electric wire 41 and the current I4 through the fourth electric wire 44 is examined in the opposite direction, the electron existing at the position X1 in the figure is shown. The magnetic field that acts on the current I1 and the magnetic field that results from the current I4 both act in the upper left direction shown in the direction of the arrow B14, and the direction of the arc current Iarc in FIG. Therefore, the electromagnetic force acts in the direction indicated by the arrow F14, that is, in the direction away from the electrode rod 1a and approaching the first electric wire 41. On the other hand, in the figure, the magnetic field acting on the electron existing at the position X4 is that both the magnetic field generated from the current I4 and the magnetic field generated from the current I1 act in the direction of the arrow B41 shown in FIG. , The electromagnetic force acts in the direction of the arrow F41 in the figure, that is, in the direction approaching the fourth electric wire 44 away from the electrode rod 1a. Therefore, the welding arc as a whole extends in the direction of the first electric wire 41 and the fourth electric wire 44 around the welding torch by the electromagnetic force acting in the F14 direction and the electromagnetic force acting in the F41 direction (region). R14 + region R41)).

  Due to the same action as described above, when the current I2 is supplied to the second electric wire 42 and the current I5 is supplied to the fifth electric wire 45, the welding arc is directed to the second electric wire 42 and the fifth electric wire 45 around the electrode rod 1a. When the current I3 is passed through the third electric wire 43 and the current I6 is passed through the sixth electric wire 46, the welding arc is centered on the electrode rod 1a. And the flat shape (area | region R36 + area | region R63) extended in the direction of the 6th electric wire 46 comes to be exhibited.

  Therefore, by switching the energization to the adjacent electric wires one after another, the flat direction of the welding arc is sequentially shifted, and it is possible to realize a state where the welding arc is rotating. In the case of FIG. 5, compared to the cases of FIGS. 3 and 4, the configuration is such that the deflection of the arc is promoted from both directions, so that the amount of arc deflection becomes larger and the arc rotation radius can be increased. Has the advantage.

(Third embodiment)
FIG. 6 is an external view of an apparatus for performing the welding method according to the third embodiment of the present invention. In addition, about the same part as 1st Embodiment, it shows with the same code | symbol and the detailed description is abbreviate | omitted.

  In the first embodiment, the electric wires 4 in the magnetic field generator 2 are arranged over the entire circumference surrounding the welding torch 1, but in this example, as shown in FIG. 6, not the entire circumference of the welding torch 1. Are arranged only on one side (right side in the figure). In theory, only one electric wire 4 may be arranged on one side, but in order to strengthen the magnetic field, a configuration in which a plurality of electric wires 4 are arranged in parallel from the back side to the front side in FIG. You may take it. Other configurations are the same as those in the first embodiment.

  In the above configuration, a welding arc is generated from the welding torch 1. Then, an arc discharge occurs in the vertical direction between the electrode rod 1a and the member A to be welded, and a welding arc is generated. And the to-be-welded member A fuse | melts with the arc heat of the generated welding arc, and welding is performed.

  Further, along with the generation of the welding arc, the magnetic field generator 2 is operated to pass a current through the electric wire 4. In this case, the direction of the current in the electric wire 4 flows from the top to the bottom so as to be substantially parallel to the welding arc formation direction (vertical direction) as shown in FIG.

  When a current flows through the electric wire 4, a magnetic field is generated around it. The direction of the generated magnetic field follows the right thumb rule.

  In this example, TIG welding is also performed. In the case of TIG welding, the electrode rod 1a side is a negative electrode, and the welded member A side is a positive electrode. Therefore, the generated arc current Iarc flows from the welded member A side to the electrode rod 1a side. That is, the arc current Iarc flows from the bottom to the top in FIG.

  As shown in FIG. 6, when the influence of electrons in the welding arc from the magnetic field B at the position X is examined, the direction of the welding current Iarc at the position X is from the bottom to the top, and the direction of the magnetic field at the X Is the direction from the near side to the far side of the paper surface indicated by the arrow B direction according to the right thumb rule, and therefore, the electromagnetic force F acts in the left direction in the figure at the position X according to the Fleming left hand rule. By this electromagnetic force F, the entire generated welding arc is deflected to the left.

  Therefore, welding at a desired position becomes possible by deflecting the arc at the arc irradiation site in the member A to be welded. This technique has an advantage that welding can be performed by arc deflection even in places where welding cannot be performed by ordinary arc welding, for example, narrow places where a welding torch does not enter.

(Fourth embodiment)
FIG. 7 is an external view of an apparatus for performing the welding method according to the fourth embodiment of the present invention. In addition, about the same part as 3rd Embodiment, it shows with the same code | symbol and the detailed description is abbreviate | omitted.

  In the third embodiment, the electric wire 4 in the magnetic field generator 2 is arranged only on one side (the right side in FIG. 6) of the welding torch 1, but in this example, as shown in FIG. They are arranged on both sides (right side and left side in FIG. 7). That is, the first magnetic field generator 2a is arranged on the right side of the welding torch 1 in the figure, and the second magnetic field generator 2a is arranged on the left side. The first magnetic field generator 2a has a DC power source 3a and a first electric wire 4a, and the second magnetic field generator 2b has a DC power source 3b and a second electric wire 4b. The first and second electric wires 4a and 4b are configured such that current flows from top to bottom in the drawing. The energization in the first magnetic field generator 2a and the second magnetic field generator 2b is controlled by a control device (not shown). Other configurations are the same as those of the third embodiment.

  In the above configuration, a welding arc is generated from the welding torch 1. Then, an arc discharge occurs in the vertical direction between the electrode rod 1a and the member A to be welded, and a welding arc is generated. And the to-be-welded member A fuse | melts with the arc heat of the generated welding arc, and welding is performed.

  Further, the first and second magnetic field generators 2a and 2b are operated together with the generation of the welding arc. At this time, the first electric wire 4a and the second electric wire 4b are connected by the first and second magnetic field generators 2a and 2b. Control is performed by a control device (not shown) so as to energize alternately.

  When only the first magnetic field generator 2a is activated and only the first electric wire 4a is energized, the welding arc generated from the electrode rod 1a is deflected to the left in the drawing based on the same principle as in the third embodiment. . On the other hand, when only the second magnetic field generator 2b is activated and only the second electric wire 4b is energized, the welding arc ARC generated from the electrode rod 1a is deflected from the right in the drawing. Therefore, by repeating the energization to the first magnetic field generator 2a and the energization to the second magnetic field generator 2b alternately and at a high speed, the irradiated portion of the arc to the member A to be welded extends in the illustrated horizontal direction.

  FIG. 8 is a view showing a distribution region of the welding arc that can be seen from the upper side of FIG. In the drawing, a circular area drawn with a dotted line is an arc formation area before energization, and an elliptical area drawn in practice is an arc formation area during energization. In the figure, B1 is the direction of the magnetic field generated at that position when the current I1 is energized, B2 is the direction of the magnetic field generated at that position when the current I2 is energized, and F1 is when the magnetic field B1 is generated The direction of Lorentz force acting on that position, F2 indicates the direction of Lorentz force acting on that position when the magnetic field B2 is generated. Of the arc forming regions at the time of energization shown in FIG. 8, regions R1 and R3 are regions in which the welding arc emitted from the electrode rod 1a is obliquely applied to the member to be welded. Decreases. On the other hand, the region R2 is a region in which the welding arc emitted from the electrode rod 1a is irradiated to the member to be welded substantially vertically, and the energy density is increased by the amount irradiated almost vertically. In such an irradiation state, the welding torch 1 is moved in the direction of the arrow P in FIGS. 7 and 8, that is, the direction along the direction in which the welding arc extends. Then, the member to be welded is first preheated with the heat of the welding arc in the region R1, and then welding is performed with the heat of the welding arc in the region R2. Finally, tempering is performed by post-heating with the heat of the welding arc in the region R3. Thus, preheating, welding, and post-heating (tempering) can be realized with a single welding torch. Moreover, it can also employ | adopt as an alternative method of heat processing or surface modification by adjusting the strength of a welding arc.

  FIG. 9 shows a modification of this example. This differs from FIG. 7 in that the magnetic field generator 2 'is provided only on one side. However, an AC power source 3 'is connected to the magnetic field generator 2', and therefore an AC current is supplied to the electric wire 4 '.

  Since an alternating current is supplied to the electric wire 4 ′, when the electric current flowing through the electric wire 4 ′ flows in the direction from the top to the bottom in the figure, the electromagnetic force acts in the left direction in the figure, and the welding arc is in the left side in the figure. To deflect. On the other hand, when flowing in the direction from bottom to top in the figure, the electromagnetic force acts in the right direction in the figure, and the welding arc is deflected from the right in the figure. Since such an action is repeated, the portion irradiated with the arc to the member A to be welded extends in the illustrated lateral direction. Therefore, as in the example of FIG. 7, preheating, welding, and post-heating can be realized with a single welding torch. Moreover, it can also employ | adopt as an alternative method of heat processing or surface modification by adjusting the strength of a welding arc.

  In addition, a magnetic field generator having an AC power source is arranged on both sides of the welding torch as shown in FIG. 7, and both the magnetic field generators are energized at a phase angle of 180 ° to extend the welding arc over a wider area. Can do.

(Fifth embodiment)
FIG. 10 is an external view of an apparatus for performing the welding method according to the fifth embodiment of the present invention, and FIG. 11 is a view showing a distribution region of a welding arc that can be seen from the upper side of FIG. In addition, about the same part as 4th Embodiment, it shows with the same code | symbol and the detailed description is abbreviate | omitted.

  In the fourth embodiment (FIG. 7), the electric wires 4 in the magnetic field generator 2 are arranged on both sides (the right side and the left side in FIG. 7) of the welding torch 1, and the welding arc is extended by the magnetic field generated from these electric wires 4. At the same time, the welding torch 1 is moved in a direction along the extending direction of the welding arc. In this example, the welding torch 1 is perpendicular to the extending direction of the welding arc (the direction of arrow P in FIGS. 10 and 11). ). Other configurations are the same as those of the fourth embodiment.

  In this example, since the welding arc is extended in a direction perpendicular to the welding direction in this way, the molten metal portion can be widely taken with respect to the welding direction. Therefore, even when the welding gap G is large, there is an advantage that welding can be sufficiently performed.

  FIG. 12 is a modification of this example, and is an example in which the magnetic field generator is provided only on one side of the welding torch and the power supply is an AC power supply, as in the modification of the fourth embodiment. . Even in this case, the same operations and effects as described above are provided.

(Sixth embodiment)
FIG. 13 is a diagram for explaining the principle in the case of performing the welding method of the sixth embodiment of the present invention, and is a schematic top view showing the arrangement configuration of the welding arc to be formed and the electric wires for applying a magnetic field. is there. In the figure, a circle drawn with a dotted line indicates a formation region of a welding arc when no magnetic field is applied. In this example, two magnetic field generators are provided, the first magnetic field generator 2a has a first electric wire 4a, and the second magnetic field generator 2b has a second electric wire 4b. The 1st electric wire 4a and the 2nd electric wire 4b are arrange | positioned as shown in FIG. That is, the two wires are not arranged so as to oppose each other with the electrode rod interposed therebetween, but are arranged so that the apex angle θ with the electrode rod at the apex is about 90 °. Arranged in this way, both magnetic field generating circuits are energized during welding. Then, at the position X1, the direction of the magnetic field is B1, the welding current Iarc is from the back side to the front side of the paper, and both of them go straight. Acts in the direction of heading. Further, at the position X2, the magnetic field direction is B2, and the welding current Iarc is from the back side to the front side of the page, so that the electromagnetic force F2 acts in the direction toward the center of the arc according to the Fleming left-hand rule. At position X3, the magnetic field generated from the first electric wire and the magnetic field generated from the second electric wire cancel each other, so that no electromagnetic force acts.

  Accordingly, the arcs at the position X1 and the position X2 move in the directions of the arrows F1 and F2 by the action of the electromagnetic force, and the arc convergence region R1 is locally formed. On the other hand, it is presumed that the portion where the electromagnetic force does not act is affected by the portion where the electromagnetic force acts, and the arc shape is distorted, resulting in the state shown in the figure.

In this way, the arc shape can be deformed. In this example, by deforming the arc shape and locally forming an arc converging part (a part with high energy density), it becomes possible to form a pre- and post-heated composite arc with one arc and weld cracking. It can be expected to be prevented and can also be used as an alternative to hybrid welding (seventh embodiment).
FIG. 14 is an external view of an apparatus for performing the welding method according to the seventh embodiment of the present invention, and FIG. The configuration of this example is basically the same as the configuration shown in FIG. 10, and only the energization control in the first electric wire 4a and the second electric wire 4b is different.

  In this example, as shown in FIG. 14, the directions of currents flowing through the first electric wire 4a and the second electric wire 4b are both directions flowing from the bottom to the top. Moreover, it supplies with electricity simultaneously to the 1st electric wire 4a and the 2nd electric wire 4b.

  Then, both wires are energized during welding. Then, as shown in FIG. 14, at the position X1, the direction of the magnetic field B1 is the direction from the back side to the front side of the page, the welding current Iarc is the vertical direction in the figure, and both are orthogonal, so the framing left hand The electromagnetic force F1 acts in the right direction in the figure. Further, at the position X2 on the opposite side across the position X1 and the electrode rod 1a, the direction of the magnetic field B2 is the direction from the near side to the far side of the paper surface, and the welding current Iarc is the vertical direction in the drawing, so the framing left hand The electromagnetic force F2 acts in the left direction in the figure.

  Therefore, the welding arc has an electromagnetic force acting in the direction approaching the first electric wire 4a side on the position X1 side (right side direction in the figure) and electromagnetic in the direction approaching the second electric wire 4b side on the position X2 side (left side direction in the figure). A force acts, and the arc as a whole is extended in the arrangement direction of the first electric wire 4a and the second electric wire 4b to exhibit a wide arc shape.

  In FIG. 15, a circular area indicated by a dotted line is an arc formation area when not energized, and an elliptical area indicated by a solid line is an arc formation area when energized. Of the arc forming regions during energization, the regions R1 and R3 are regions in which the welding arc emitted from the electrode rod 1a is obliquely applied to the member to be welded, and the energy density is reduced by the amount irradiated obliquely. On the other hand, the region R2 is a region in which the welding arc emitted from the electrode rod 1a is irradiated to the member to be welded substantially vertically, and the energy density is increased by the amount irradiated almost vertically. In such an irradiation situation, when welding is performed by moving the welding torch in the direction of the arrow Q in FIG. 15, that is, the direction parallel to the direction in which the welding arc extends, the member to be welded is first heated by the heat of the welding arc in the region R1. Preheating is performed, and then welding is performed with the heat of the welding arc in the region R2. Finally, tempering is performed by post-heating with the heat of the welding arc in the region R3. Thus, preheating, welding, and post-heating (tempering) can be realized with a single welding torch. Moreover, it can also employ | adopt as an alternative method of heat processing or surface modification by adjusting the strength of a welding arc.

  On the other hand, when the welding torch 1 is moved in the direction of the arrow P in FIG. 15, that is, the direction orthogonal to the direction in which the welding arc extends, welding can be performed in a wide area with respect to the traveling direction of the welding torch. It is possible to perform welding with a wide gap.

  In the above example, the welding current Iarc and the direction of the current flowing through the electric wires 4a and 4b are set to the same direction, but they may be reversed. In such a case, the wide direction of the arc is a direction orthogonal to the above example.

(Eighth embodiment)
FIG. 16 is an external view of an apparatus for performing the welding method according to the eighth embodiment of the present invention. The configuration of this example is basically the same as the configuration shown in FIG. 10, and only the energization control and the fusion target in the first electric wire 4a and the second electric wire 4b are different.

  In this example, as shown in FIG. 16, the directions of currents flowing through the first electric wire 4a and the second electric wire 4b are both directions flowing from top to bottom. Moreover, it supplies with electricity simultaneously to the 1st electric wire 4a and the 2nd electric wire 4b.

  In the above configuration, when welding is performed, a welding arc is generated, and the member to be welded is melted by the arc heat. And the metal molten pool S is formed. In the formed molten metal pool S, at the position X1, the direction of the magnetic field B1 is the direction from the front side to the back side of the paper surface, the welding current Iarc is the direction from the bottom to the top side, and both are orthogonal. In accordance with Fleming's left-hand rule, the electromagnetic force F1 acts in the direction toward the center of the molten metal pool S. Further, at the position X2 on the opposite side across the position X1 and the electrode rod 1a, the direction of the magnetic field B2 is the direction from the back side to the front side of the page, and the welding current Iarc is the direction from the bottom to the top. In accordance with Fleming's left-hand rule, the electromagnetic force F2 acts in the direction toward the center of the molten metal pool S.

  Therefore, in the molten metal pool S, the molten metal receives electromagnetic force from the edge side toward the center, and the molten metal flows in the center of the molten metal pool S. When the molten metal flows in this way, the molten metal sinks from the center of the molten pool as shown by the arrow W1 in the figure and flows to the bottom of the pond, and further flows from the bottom to the edge as shown by the arrow W2. Form a convection state. Such a convection state is a flow opposite to the convection state caused by plasma air flow or Marangoni convection (convection by surface tension) generated by normal arc welding, and the molten metal enters the bottom surface of the molten metal S and melts. Since the effect of colliding with the bottom of the pond and further melting the bottom surface can be expected, there is an advantage that the welding penetration depth can be further increased.

  The first to seventh embodiments have been described by taking TIG welding as an example, but it is apparent that the present invention can also be applied to non-molten electrode welding other than TIG welding. Furthermore, the present invention can also be applied to welding electrode type welding such as MAG welding and MIG welding. However, in MAG welding or the like, since the welding wire is a negative electrode and the member to be welded is a positive electrode, and the welding current flows in reverse to TIG welding, it is necessary to reverse the current flowing in each wire.

(Ninth embodiment)
FIG. 17 is a schematic view showing a method for controlling metal droplets according to the eighth embodiment of the present invention. In this example, an example of MAG welding which is a welding electrode type welding is illustrated. As shown in the figure, the welding torch 1 is arranged such that the tip of the welding rod 1a faces downward. In addition, an object A to be welded is disposed below the welding torch 1 with a predetermined spatial distance.

  A first magnetic field generator 2a is disposed on the right side of the welding torch 1 and the work A to be welded, and a second magnetic field generator 2b is disposed on the left side of the figure. The first magnetic field generator 2a includes a first DC power source 3a and a first electric wire 4a electrically connected to the first DC power source 3a. Similarly, the 2nd magnetic field generator 2b is provided with the 2nd DC power supply 3b and the 2nd electric wire 4b electrically connected to this 2nd DC power supply 3b. The first electric wire 4a (second electric wire 4b) is arranged in the vertical direction in the figure, and one end (upper end) is connected to the negative electrode of the first power source 3a (second power source 3b) and the other end (lower end) is the first. The first power source 3a (second power source 3b) is connected to the positive electrode. Therefore, when the electric wires 4a and 4b are energized, the current flows from the lower side to the upper side of the electric wires 4a and 4b.

  In the above configuration, a welding arc is generated from the welding torch 1. Then, an arc discharge occurs in the vertical direction between the welding rod 1a and the member A to be welded, and a welding arc is generated. And the welding rod 1a and the to-be-welded member A fuse | melt with the arc heat of the generated welding arc, and welding is performed.

  In MAG welding, a welding rod, which is an electrode, is melted by arc heat and is dropped as a metal droplet into a weld pool of a member to be welded. At this time, a magnetic field is applied to the welding arc. Thus, an electromagnetic force is generated, and the dropping point of the metal droplet is controlled by the electromagnetic force.

  That is, when the first magnetic field generating device 2a and the second magnetic field generating device 2b are operated during welding and the first electric wire 4a and the second electric wire 4b are energized, the current flows in each electric wire from the bottom to the top in the figure. Flowing. In this case, when the magnetic field at the position X1 in the figure is examined, the magnetic field generated by the first electric wire 4a is dominant at this position, and as a result, the direction of the magnetic field is from the back side to the front side of the paper as shown in the figure. It becomes the direction toward On the other hand, an arc current acts on the metal droplet at the position X1, and the direction of the arc current is from the upper direction to the lower direction in the figure, so the Lorentz force force is the center of the arc indicated by the F1 direction in the drawing. Acts to the side. In response to this Lorentz force F1, the metal droplet at the position X1 falls on the member to be welded while moving toward the center of the arc.

  On the other hand, when the magnetic field at the position X2 in the figure is examined, the magnetic field generated by the second electric wire 4b becomes dominant at this position, and as a result, the direction of the magnetic field is directed from the front side to the back side as shown in the figure. Direction. On the other hand, since an arc current acts on the metal droplet at the position X2, and the direction of the arc current is from the upper direction to the lower direction in the drawing, the Lorentz force is the position X2 as shown in the F2 direction in the drawing. Acts in the direction from the arc toward the center of the arc. In response to this Lorentz force F2, the metal droplet at the position X2 falls to the member to be welded while moving toward the center of the arc.

  That is, by operating the magnetic field generator as in this example and energizing each electric wire, the metal droplets that have melted from the welding rod can be collected in the center. Therefore, it is possible to reliably drop droplets scattered as spatter out of the molten pool into the molten pool, reduce spatter, reduce the man-hours for removing spatter adhering to the workpiece, and prevent the spatter from adhering. A great effect in practical use such as abolition can be expected.

(Tenth embodiment)
FIG. 18 is a schematic diagram showing a metal droplet control method according to the tenth embodiment of the present invention. In this example, unlike the eighth embodiment, the magnetic field generator 2 is provided only on one side of the welding torch. Other configurations are the same as those of the eighth embodiment.

  In such an apparatus configuration, the metal droplet is affected by the magnetic field generated from the electric wire 4. The direction of the magnetic field B1 is a direction from the back side to the front side as shown in the figure. On the other hand, an arc current is acting on the metal droplet, and since the direction of the arc current Iarc is from the upper direction to the lower direction in the figure, the Lorentz force acting on the metal droplet is indicated by the F1 direction in the drawing. Acts to the left. In response to this Lorentz force F1, the metal droplet falls on the member to be welded while shifting in the left direction in the figure. By shifting in this way, it is possible to control spatter scattering in a specific arbitrary direction, preventing spatter adhesion to parts where spatter scattering is undesirable, reducing the number of work steps for removing adhering spatter, and spatter adhesion It can be expected to have a great practical effect, such as the abolition of the cover to prevent this.

It is the schematic of the apparatus structure which performs the control method of the welding arc in the example of 1st Embodiment of this invention. FIG. 1 shows the positional relationship between the welding arc generated in the first embodiment of the present invention and the electric wires of the magnetic field generator, the direction of the magnetic field generated from each electric wire, and the direction of the Lorentz force acting at each position in the welding arc. It is the figure seen from the upper side. It is the schematic which shows the control principle of the welding arc in 2nd Embodiment of this invention, In the arrangement | positioning relationship between the welding arc which generate | occur | produces in 2nd Embodiment, and the electric wire of a magnetic field generator, In each position in a welding arc It is the figure which showed the direction of the Lorentz force which act | operates. It is a figure which shows the control principle of the welding arc in the modification of the 2nd Embodiment of this invention. It is a figure which shows the control principle of the welding arc in another modification of the 2nd Embodiment of this invention. It is the schematic of the apparatus structure which performs the control method of the welding arc in the example of 3rd Embodiment of this invention. It is the schematic of the apparatus structure which performs the control method of the welding arc in the example of 4th Embodiment of this invention. It is a figure which shows the formation area of the welding arc in the example of 4th Embodiment of this invention. It is the schematic of the apparatus structure which performs the control method of the welding arc in the modification of the example of 4th Embodiment of this invention. It is the schematic of the apparatus structure which performs the control method of the welding arc in the example of 5th Embodiment of this invention. It is a figure which shows the formation area of the welding arc in the example of 5th Embodiment of this invention. It is the schematic of the apparatus structure which performs the control method of the welding arc in the modification of 5th Example of this invention. It is a figure which shows the arrangement configuration of the electric wire for applying the welding arc and magnetic field which are formed in the 6th Example of this invention. It is the schematic of the apparatus structure which performs the control method of the welding arc in the example of 7th Embodiment of this invention. It is the figure which showed the formation area of the welding arc in the example of 7th Embodiment of this invention. It is the schematic of the apparatus structure which performs the control method of the metal molten pool in the 8th Example of this invention. It is the schematic of the apparatus structure which performs the control method of a metal droplet in the 9th Example of this invention. It is the schematic of the apparatus structure which performs the control method of a metal droplet in the 10th Example of this invention.

Explanation of symbols

1: welding torch 1a: electrode rod 2, 2 'magnetic field generator 2a: first magnetic field generator, 2b: second magnetic field generators 3, 3', 3a, 3b: power supply 4: electric wire (current path)
4a: first electric wire (current path), 4b: second electric wire (current path)
41: First electric wire (current path)
42: Second electric wire (current path)
43: Third electric wire (current path)
44: Fourth electric wire (current path)
45: Fifth electric wire (current path)
46: 6th electric wire (current path)

Claims (8)

A current path through which a current flows in a direction substantially parallel to the flow direction of the charged particle flow is formed, and a magnetic field generated around the current path when the current path is energized is applied to the charged particles in the charged particle flow. A charged particle flow control method, wherein a Lorentz force is generated by applying the Lorentz force, and the charged particle flow is controlled by the generated Lorentz force. In claim 1,
A method for controlling a charged particle flow, wherein a plurality of the current paths are formed so as to surround a periphery of the flow of the charged particle flow, and a direct current is passed through the plurality of current paths in the same direction and simultaneously. . In claim 1,
A plurality of the current paths are formed so as to surround a periphery of the flow of the charged particle flow, and a direct current is allowed to flow through the plurality of current paths in the same direction and sequentially. Control method. In claim 1,
A method for controlling a charged particle flow, wherein at least two current paths are formed on both sides of the flow of the charged particle flow, and a direct current is passed through the two current paths in the same direction. In claim 1,
A method for controlling a charged particle flow, comprising forming at least one current path on one side of a flow of a charged particle flow and causing an alternating current to flow through the current path. In any one of Claims 1-5,
The method for controlling a charged particle flow, wherein the charged particle flow is a welding arc or plasma. A magnetic field generated around the current path when a current path is formed in which the current flows in a direction substantially parallel to the flow direction of the current passing through the molten metal formed by arc welding. A method of controlling a molten metal, wherein a Lorentz force is generated by acting on charged particles in the molten metal, and the molten metal is controlled by the generated Lorentz force. In claim 7,
At least two current paths are formed on both sides of the current flow passing through the molten metal, and the current is passed through the two current paths in the same direction and opposite to the current flow direction passing through the molten metal. A method for controlling molten metal, characterized by flowing in a direction.

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