JP2008115285A - Method for joining metal member and apparatus therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and an apparatus for joining metal members which can efficiently cure or semi-cure an adhesive in a joining process using a thermosetting adhesive without necessitating large equipment. <P>SOLUTION: This method or apparatus for joining a plurality of superposed metal members 100 through interposing a thermosetting adhesive between the members comprises generating a magnetic field at the joining part of the metal members 100 by magnets 71a and 71b, generating induction currents in the metal members 100 by varying the magnetic field, and accelerating heating and curing of the thermosetting adhesive through heat evolution of the metal members 100 by the induction current. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method and an apparatus for joining a plurality of stacked metal members with a thermosetting adhesive interposed therebetween.

  Conventionally, spot welding is generally performed as a method of joining metal members to each other in the body of an automobile. However, in recent years, there has been an increasing demand for improvement in collision performance, and therefore, spot welding sometimes has insufficient strength. This is because in spot welding, the joints are discontinuous, so stress concentration is likely to occur, and the joints peel off relatively easily at the time of collision.

  Therefore, in recent years, bonding with an adhesive is being frequently used to solve the problem. According to the adhesive, since it is possible to join at continuous joining points, there is an advantage that it is difficult to peel off at the time of collision as compared with joining by spot welding. As the adhesive to be used, a thermosetting structural adhesive represented by an epoxy adhesive is generally used.

  As a series of flows including a bonding process using an adhesive, for example, as seen in an automobile body manufacturing process, a bonding process using an adhesive, an electrodeposition coating process, and a painting drying process are often performed in this order. In this case, curing of the adhesive is performed using heating in the paint drying process. That is, productivity is improved by simultaneously drying the coating and curing the adhesive.

In addition, although it is not joining using an adhesive agent, what is shown in Patent Document 1 is known as a method of joining stacked metal members. This method is a friction point welding in which the tip of a cylindrical rotary tool is pushed into a metal member and the metal member is softened by the frictional heat to cause plastic flow (referred to as friction stir welding in Patent Document 1). ). In Patent Document 1, a plurality of magnets are attached so that different magnetisms are alternately arranged in the rotation direction around the rotary tool. If it does in this way, while the magnetic field by a magnet will arise in the vicinity of a joined part, a magnetic field will change with rotation of a rotary tool. As a result, an induced current is generated in the metal member and heat is generated. This heat generation can promote softening of the metal member and facilitate plastic flow.
JP 2005-324246 A

  However, when another process (for example, an electrodeposition coating process) is performed between the bonding process using an adhesive and the process for curing the adhesive (for example, a paint drying process) as described above, various problems occur.

  First of all, there is a problem that misalignment occurs during conveyance because the adhesive is uncured. On the other hand, it can be dealt with by temporarily fixing by spot welding or the like, but it is not preferable to add a new process from the viewpoint of productivity.

  Secondly, there is a problem that the adhesive protruding from the application part adheres to a jig or other workpiece in the process via the operator. In this case, enormous costs and time are required for wiping off the adhesive adhered to the jig or workpiece.

  Third, in the electrodeposition coating process, there is a problem that the adhesive is released in each of the cleaning, chemical conversion treatment, and electrodeposition liquid baths. The released adhesive stains each liquid or adheres again to the work (such as the body outer plate of an automobile).

  In order to solve the first to third problems, the adhesive is cured or at least semi-cured to a level at which each of the above problems does not occur immediately after the joining process or immediately after that (before moving to the electrodeposition coating process). It is considered good. However, in the conventional method, that is, the method of heat-curing in a heat treatment furnace similar to a paint drying furnace, a large equipment investment and a large space are required to heat treat the entire workpiece. In addition, it takes time to transfer heat because it uses radiant heat, and the temperature at the interface where the adhesive is applied is unlikely to rise.

  In view of the circumstances as described above, the present invention provides a metal member joining method capable of efficiently curing or semi-curing an adhesive in a joining process using a thermosetting adhesive without requiring a large amount of equipment, and its An object is to provide an apparatus.

  The invention according to claim 1 for solving the above-mentioned problem is a method of joining by interposing a thermosetting adhesive between a plurality of stacked metal members, and using a magnet at the joint of the metal members. A magnetic field is generated, an induced current is generated in the metal member by changing the magnetic field, and heat curing of the thermosetting adhesive is promoted by heat generation of the metal member by the induced current.

  According to a second aspect of the present invention, in the method for joining metal members according to the first aspect, a magnet unit in which a plurality of magnets are arranged so that different polarities are alternately arranged in a direction intersecting with the overlapping direction of the metal members. The magnetic field is changed by preparing and moving the magnet unit in the magnet arrangement direction.

  According to a third aspect of the present invention, in the method for joining metal members according to the second aspect, the pair of magnet units are arranged to face each other with the joint portion interposed therebetween, and at least one of the magnet units is moved to move the magnetic field. It is characterized by making changes.

  According to a fourth aspect of the present invention, in the method for joining metal members according to the second or third aspect, the magnet unit is attached to a rotary tool having a rotation axis substantially parallel to the overlapping direction of the metal members, and the rotary tool is mounted. The magnet unit is moved by being positioned and rotated in the vicinity of the joint portion of the metal member.

  According to a fifth aspect of the present invention, in the method for joining metal members according to the fourth aspect, a processing portion is provided at a tip portion of the rotary tool that faces the metal member, and the processing portion is provided while rotating the rotary tool. The metal member is pushed into the metal member to generate frictional heat, and the frictional heat and the heat generated by the induced current soften the metal member to cause plastic flow and join, and accelerate the thermosetting of the thermosetting adhesive. It is characterized by making it.

  The invention according to claim 6 is the method for joining metal members according to claim 4 or 5, wherein the joint part of the metal member is provided in a range wider than the rotation trajectory of the rotary tool, and the rotary tool is provided on the joint part. It is moved within an expanding range, and the heat curing of the thermosetting adhesive is promoted continuously or intermittently along the movement trajectory.

  The invention according to claim 7 is an apparatus for joining by interposing a thermosetting adhesive between a plurality of stacked metal members, the magnet generating a magnetic field at the joint of the metal members, and the magnetic field Magnetic field changing means for generating an induced current in the metal member by changing the temperature of the metal member, and heat curing of the thermosetting adhesive is promoted by heat generation of the metal member by the induced current.

  According to an eighth aspect of the present invention, in the metal member joining apparatus according to the seventh aspect, a plurality of the magnets are arranged so that different polarities are alternately arranged in a direction intersecting with the overlapping direction of the metal members. The magnetic field changing means moves the magnet unit in the direction in which the magnets are arranged.

  According to a ninth aspect of the present invention, in the apparatus for joining metal members according to the eighth aspect, the pair of magnet units are arranged to face each other with the joint portion interposed therebetween, and the magnetic field changing means moves at least one of the magnet units. It is a thing to let it be.

  According to a tenth aspect of the present invention, in the metal member joining apparatus according to the eighth or ninth aspect, the magnetic field changing means has a rotation axis substantially parallel to the overlapping direction of the metal members and the magnet unit is attached thereto. A rotating tool, wherein the magnet unit is moved by rotating the rotating tool in the vicinity of the joint portion of the metal member.

  According to an eleventh aspect of the present invention, in the metal member joining apparatus according to the tenth aspect, the rotary tool includes a processing portion at a tip portion facing the metal member, and the processing portion is arranged while rotating the rotary tool. The metal member is pushed into the metal member to generate frictional heat, and the frictional heat and the heat generated by the induced current soften the metal member to cause plastic flow and join, and accelerate the thermosetting of the thermosetting adhesive. It is characterized by making it.

  The invention according to claim 12 is the metal member joining apparatus according to claim 10 or 11, further comprising movement control means for moving the rotary tool in a direction intersecting at least the rotation axis thereof, wherein the movement control means comprises the rotation The tool is moved along a range where the joint is widened, and the heat curing of the thermosetting adhesive is promoted continuously or intermittently along the movement trajectory.

  According to a thirteenth aspect of the present invention, in the metal member joining apparatus according to the twelfth aspect of the invention, the movement control means is a robot having the rotary tool mounted at the tip and a driving means for driving the rotary tool to rotate. It is characterized by being.

  According to the first aspect of the present invention, as described below, the adhesive can be efficiently cured or semi-cured in the joining step using the thermosetting adhesive without requiring a large amount of equipment.

  According to the configuration of the present invention, since the adhesive can be cured only by arranging the magnet around the joint and changing the magnetic field thereof, a large heat treatment furnace or the like that accommodates the entire workpiece is not required. That is, it is possible to avoid a large capital investment and a large space.

  Further, since the metal member is directly heated by the induced current, there is less energy loss compared to the conventional method using radiant heat, and it can be cured in a short time.

  Furthermore, since a magnet is used, an attractive force acts between the metal members, and the effect that the mutual gap can be reduced can also be expected.

  As the magnet, a permanent magnet or an electromagnet may be used. As the permanent magnet, a neodymium magnet, an alnico magnet, a samarium cobalt magnet or the like is preferable. As a method of changing the magnetic field, in addition to moving (including rotating) a magnet (including an electromagnet), in the case of an electromagnet, the magnetic field may be changed by changing an electric current.

  The present invention is not intended to limit the degree of curing. If the adhesive is completely cured by the method of the present invention, it is a matter of course that the above problems can be solved, but it is not always necessary to completely cure the adhesive. For example, it is sufficient to cure to such an extent that the above problems do not occur. Alternatively, it may be cured to such an extent that some of the above problems can be solved, and the remaining problems may be solved by other means. Hereinafter, in this specification, curing to the required level is referred to as semi-curing.

  When an electrodeposition coating process or the like is refrained from the later process, it is desirable to keep the degree of curing semi-cured. This is because the second half of the heat curing process can be performed using the paint drying process, which is efficient.

  According to invention of Claim 2, a magnetic field can be easily changed only by moving the magnet unit arrange | positioned so that different polarities may line up alternately (including rotation).

  According to the invention of claim 3, the magnetic flux density is changed by moving at least one of the magnet units while maintaining the state in which the magnetic flux penetrates the metal member by the pair of magnet units, and an induced current is generated in the metal member. be able to. Accordingly, the temperature of the joint can be increased more reliably and efficiently.

  According to the invention of claim 4, the magnet unit can be easily moved by simply attaching the magnet unit to the rotary tool and rotating the rotary tool. Further, the heating temperature can be easily adjusted by controlling the distance between the rotary tool and the metal member and the number of rotations of the rotary tool.

  According to the invention of claim 5, in addition to the heat generated by the induced current, the frictional heat generated by pushing the processed portion can be used, so that the adhesive can be more efficiently cured by the synergistic effect. Further, the joining of the metal members can depend not only on the adhesive but also on the joining by plastic flow. Therefore, for example, it is possible to reduce the share of the bonding force of the adhesive with respect to the bonding force required for preventing displacement (temporary fixing). That is, it can be expected to reduce the degree of semi-curing required for the adhesive.

  According to the invention of claim 6, even if the joining range (application range of the adhesive) is wide, it is not necessary to use a rotary tool that covers the whole, and the equipment can be made more compact.

  According to invention of Claims 7-12, the joining apparatus which show | plays the effect according to each item of the said Claims 1-6 can be obtained easily.

  According to the invention of claim 13, by using a highly versatile robot as the movement control means for moving the rotary tool at least in the direction crossing the rotation axis, the rotary tool can be easily and freely moved, As an adaptation flexibility can be enhanced.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a schematic configuration diagram of a metal member joining apparatus 1 (hereinafter abbreviated as a joining apparatus 1) according to a first embodiment of the present invention. The joining apparatus 1 includes a joining gun unit 10 and a robot 40 including the joining gun unit 10 on a wrist as main components.

  The joining gun unit 10 is composed of a pair of joining guns 10a arranged to face each other. A rotary tool 70 is attached to the tip of each joining gun 10a, and they are arranged to face each other. A magnet unit 71 composed of a plurality of magnets is attached to the rotary tool 70. The magnet unit 71 will be described in detail later. A magnetic field is generated between the magnet unit 71 and the magnet unit 71 facing each other, and the magnetic field is changed by rotating at least one of the magnet unit 71 (the rotary tool 70). Is configured to do.

  As the robot 40, a general-purpose 6-axis vertical articulated robot is used in this embodiment. The robot 40 is connected to the control panel 50 via a harness 51. Each joining gun 10 a is connected to the control panel 50 via harnesses 52, 54, 55 and a repeater 53. A control unit 50a is built in the control panel 50, and controls the robot 40 to operate the joining gun 10a so as to have a predetermined position and inclination set in advance. In addition, the control unit 50a controls a lifting motor 14 and a rotation motor 15 (see FIG. 2), which will be described later, mounted on the joining gun 10a, and a pair of rotary tools disposed opposite to the tip of each joining gun 10a. 70 is caused to perform a predetermined operation set in advance.

  2 is a front view of the joining gun 10a, and FIG. 3 is a side view of the joining gun 10a (each mainly showing one side). As shown in these drawings, the joining gun 10a includes an arm 12 that branches in two directions from the wrist of the robot 40, a mounting box 11 attached to the arm 12, and a body case attached to the side surface of the mounting box 11. 13, a lifting motor 14 connected to a harness 54, and a rotating motor 15 connected to a harness 55. A rotating tool 70 is attached to the lower end of the main body case 13.

  The joining of the metal members by the joining device 1 is performed by sandwiching the metal member (workpiece 100) that has been coated with an adhesive in a non-contact manner between the rotary tools 70 and rotating the rotary tool 70 to rotate the magnet unit 71. The induced magnetic field is generated in the workpiece 100 by changing the magnetic field caused by the above, and the curing of the adhesive is promoted by the heat generated thereby.

  4 is a cross-sectional view showing the internal structure of the main body case 13, and FIG. 5 is a cross-sectional view taken along the line VV of FIG. Although the vertical relationship at the time of operation in the joining gun unit 10 can be freely changed, for convenience of explanation, in the following description, the main body case 13 side is set to the upper side and the rotary tool 70 side is set to the lower side.

  Inside the main body case 13, screw shafts (elevating shafts) 24 and spline shafts (rotating shafts) 25 extending in the vertical direction in parallel with each other are provided so as to be rotatable around respective axis centers. The upper ends of the shafts 24 and 25 penetrate the upper lid member 21 and reach the upper cover 22, where the driven pulleys 26 and 27 are assembled to the shafts 24 and 25, respectively. As shown in FIG. 5, the upper lid member 21 and the upper cover 22 project from the upper part of the main body case 13 to the side of the main body case 13. The motor 15 is fixed. The front end portions (upper end portions) of the output shafts 14a and 15a of both the motors 14 and 15 pass through the upper lid member 21 and reach the upper cover 22, where drive pulleys 14b and 15b are connected to the output shafts 14a and 15a. Each is assembled. Drive transmission belts 28 and 29 are wound between the drive pulleys 14b and 15b and the driven pulleys 26 and 27, respectively, and the screw shaft 24 is shown in FIG. 5 is rotated in the A direction (down direction) or the B direction (up direction), and the rotation of the motor 15 for rotation causes the spline shaft 25 to be rotationally driven in the C direction of FIG.

  Returning to FIG. 4, the description will be continued. The elevating block 31 is screwed to the screw portion 24 a of the screw shaft 24, and the rotating cylinder 35 is splined to the spline portion 25 a of the spline shaft 25. The rotating cylinder 35 is rotatably provided inside an elevating cylinder 33 integrally coupled to the elevating block 31 via a coupling member 32. The spline shaft 25, the elevating cylinder 33, and the rotating cylinder 35 are arranged concentrically with each other. Hereinafter, an integrated body of the lifting block 31, the coupling member 32, and the lifting cylinder 33 is referred to as a lifting body 30.

  A cylindrical downward projecting portion 13a is formed on the lower surface of the main body case 13, and a lower cover 23 is provided at the lower end portion of the downward projecting portion 13a. The lower end portions of the elevating cylinder body 33 and the rotating cylinder body 35 penetrate the lower cover 23 and protrude downward. The rotating cylinder 35 on the inner side protrudes downward longer than the lifting cylinder 33 on the outer side, and the attachment member 36 is fixed to the lower end portion of the rotating cylinder 35. A rotary shaft 73 of the rotary tool 70 is detachably attached to the attachment member 36 (changeable). The rotation axis of the attached rotary tool 70 is on the extension line of the axis of the spline shaft 25. An extendable bellows member 34 is disposed between the lower cover 23 and the lower end of the elevating cylinder 33 to protect the outer surface of the elevating cylinder 33 from contamination outside the main body case 13. .

  A bearing 25b is provided between the spline shaft 25 and the upper lid member 21, a bearing 35a is provided between the elevating cylinder 33 and the rotating cylinder 35, and a bearing is provided between the elevating cylinder 33 and the mounting member 36. 33a are provided.

  Further, the lift motor 14 is preferably a servo motor that can easily control and detect the rotation angle, and the rotation motor 15 can be a servo motor that can easily control and detect the rotation angle, or can easily control the rotation speed. Induction mode is preferred.

  FIG. 6 is an explanatory diagram of the structure of the rotary tool 70. The rotary tool 70 includes a rotary shaft 73 attached to the attachment member 36 and a flat disk portion 74 provided at the tip thereof. Further, a magnet unit 71 is attached to the tip of the disc portion 74. The main part of the magnet unit 71 is composed of six permanent magnets arranged so that different magnetic poles are alternately arranged in the rotation direction of the rotary tool 70. Specifically, three N-arranged magnets 71a and three S-arranged magnets 71b are alternately arranged. The N-arranged magnet 71a is a magnet arranged so that the distal end side is an N pole and the proximal end side (disc portion 74 side) is an S pole. On the other hand, the S-arranged magnet 71b is a magnet arranged so that the tip side is the S pole and the base end side (the disk portion 74 side) is the N pole. As the N-arranged magnet 71a and the S-arranged magnet 71b, a neodymium magnet, an alnico magnet, a samarium cobalt magnet or the like having a strong magnetic force is preferable.

  Moreover, it arrange | positions so that different magnetism may oppose in the magnet units 71 which oppose. Accordingly, the magnetic flux 80 is generated substantially in parallel up and down so as to penetrate the workpiece 100. In the present embodiment, the pair of rotary tools 70 rotate at the same rotational speed in the same direction while maintaining the relationship (indicated by arrows A1 and A2). Therefore, the position is confirmed by an encoder or the like as necessary, and synchronization is achieved.

  Next, a method for joining metal members using the joining apparatus 1 will be described. FIG. 7 is a schematic diagram showing a joining process of a metal member using an adhesive. The workpieces 100 to be joined in this step are a metal member 101 having a reverse hat cross section and a metal member 103 having a flat plate shape. The metal members 101 and 103 are preferably, for example, an aluminum alloy plate or a steel plate.

  The upper part of FIG. 7 shows a state where the adhesive 102 is applied to the flange portion of the metal member 101. The adhesive 102 is a one-component heat curable adhesive (thermosetting adhesive) mainly composed of an epoxy resin. As curing conditions, those of 140 to 160 ° C. × 20 minutes, 80 ° C. × 60 minutes (low temperature curing type) and the like are suitable.

  The middle part of FIG. 7 shows a state in which the metal member 103 is subsequently superimposed on the metal member 101.

  The lower part of FIG. 7 shows a process of subsequently heat-curing the adhesive 102. Here, in order to simplify the drawing, only the rotary tool 70 of the joining apparatus 1 is shown. As shown in this figure, first, the rotary tool 70 is set by the robot 40 near one end of the adhesive 102 extending linearly. At this time, the workpiece 100 is adjusted so as to be sandwiched between the pair of rotary tools 70 in a non-contact state.

  The raising / lowering operation | movement of the rotary tool 70 for that is demonstrated. When the screw shaft 24 is driven to rotate in the direction A in FIG. 5 by the rotation of the lifting motor 14, the lifting body 30 is lowered by screwing with the screw portion 24 a and is installed in the lifting cylinder 33 in the lifting body 30. The rotary cylinder 35 and the rotary tool 70 attached to the lower end portion of the rotary cylinder 35 via the attachment member 36 are lowered together. Conversely, when the screw shaft 24 is rotationally driven in the direction B of FIG. 5 by the rotation of the lifting motor 14, the lifting body 30 is lifted by screwing with the screw portion 24a, and the rotary cylinder 35 and the rotary tool 70 are moved. Rise together.

  By performing such an elevating operation with a pair of rotary tools 70 (may be performed with only one rotary tool 70), a predetermined gap is provided between the magnet unit 71 and the workpiece 100 so as to sandwich the joint portion. A pair of magnet units 71 can be arranged to face each other.

  At this time, a magnetic field is formed between the pair of magnet units 71, and the workpiece 100 exists in the magnetic field. The magnetic flux 80 at that time is arranged substantially perpendicularly to the plate surface so as to penetrate the workpiece 100 as shown in FIG. At this time, an attractive force acts between the metal member 101 and the adhesive 102 by the magnetic force of the magnet unit 71 that sandwiches the workpiece 100, and the mutual gap is reduced. Therefore, the adhesive effect of the adhesive 102 can be promoted.

  Next, the rotary tool 70 is rotationally driven. To rotate the rotary tool 70, the rotation motor 15 is driven, and the spline shaft 25 is driven to rotate in the direction C in FIG. In this way, independent of the movement of the lifting body 30, the rotating cylinder 35 rotates in the same C direction as the spline shaft 25 by spline coupling with the spline portion 25 a, and the rotating tool 70 attached to the rotating cylinder 35 is also It rotates in the same C direction as the spline shaft 25 around the rotation shaft 73. In addition, the rotation motor 15 can change the rotation speed (rotation speed) of the rotary tool 70 by a current supplied to the rotation motor 15.

  The pair of rotary tools 70 are controlled by the control unit 50a so as to rotate in the same direction at the same rotational speed (arrows A1, A2). Further, the position of the magnet unit 71 is confirmed sequentially by an encoder or the like not shown in the figure, and synchronization is always taken so that different magnetic magnets face each other. If it does in this way, magnetic flux 80 will follow the rotation of rotary tool 70, and will move in parallel, drawing the locus of an arc. This changes the magnetic flux density at each point of the workpiece 100. That is, the magnetic field changes. Due to the change in the magnetic field, an induced current is generated in the workpiece 100 near the region sandwiched between the rotary tools 70, and the workpiece 100 generates heat due to the induced current. The heat generation promotes the curing of the adhesive 102.

  If the workpiece 100 is heated at a temperature and time corresponding to the above curing conditions, the adhesive 102 is completely cured. For example, when the process of heating the workpiece 100 later is not kept, the heat curing process may be completed as such. However, when a process of heating the workpiece 100 is refrained later, such as a paint drying process, it is desirable to semi-cure to a required hardness until that process and keep it temporarily fixed. This is because the latter half of the heat curing process can be performed using the process (paint drying process or the like), which is efficient.

  The pair of rotary tools 70 are sequentially moved by the robot 40 in the direction in which the adhesive 102 extends (arrow A3). The slower the moving speed, the higher the curing acceleration effect, and the faster the moving speed, the shorter the time (tact) required for the joining process. Further, the moving speed may be constant or may be moderate. When it is moved at a constant speed, a uniform curing acceleration effect is obtained, and when it is moved slowly and slowly, a portion with a relatively high degree of curing acceleration can be obtained although it is a relatively short tact. it can. In this way, when the heat curing acceleration of all the places is completed, the joining process is completed.

  In the present embodiment, as shown in FIG. 6, the pair of rotary tools 70 are rotated in the same direction while being synchronized, but it is not always necessary to do so. For example, the following modifications may be used.

  FIG. 8 is an explanatory view showing a modification of the rotating operation of the rotary tool 70. In this modification, the pair of rotary tools 70 are rotated in opposite directions (arrows A1, A4). Therefore, as viewed from each N-arranged magnet 71a and S-arranged magnet 71b, the case where the opposing magnets have different polarities (left side in FIG. 8) and the case where they have the same polarity (right side in FIG. 8) are repeated alternately. Will be. When the opposing magnets have different polarities, the magnetic flux 80 intersects the plate surface of the workpiece 100 at a substantially right angle as in the case of FIG. On the other hand, when the opposing magnets have the same polarity, the magnetic flux 80 is formed between the magnets adjacent to the opposing magnets (which become magnets having different polarities). That is, the magnetic flux 80 intersects the plate surface of the workpiece 100 obliquely. As described above, the magnetic flux 80 alternately changes between a state in which the magnetic flux 80 intersects at right angles to the plate surface of the workpiece 100 and a state in which the magnetic flux 80 intersects obliquely. That is, the magnetic field changes and an induced current is generated in the workpiece 100, which generates heat.

  According to this modification, there is an advantage that an encoder or the like can be omitted because there is no need to synchronize rotation.

  FIG. 9 is an explanatory view showing another modified example of the rotating operation of the rotary tool 70. In this modification, only one (upper side in the figure) of the pair of rotary tools 70 is rotated (arrow A1). Also in this case, similarly to the above-described modification, when the opposing magnets have the same polarity as viewed from the N-arranged magnets 71a and S-arranged magnets 71b (left side in FIG. 9) ( And the right side of FIG. 9 appear alternately.

  Similarly to the above modification, this modification has the advantage that the encoder and the like can be omitted because it is not necessary to synchronize the rotation. However, since the relative speed (change speed of magnetic flux density) between the rotating tools 70 is slower than the modification shown in FIG. 8 if the conditions such as the rotational speed are the same, the heating ability is relatively lowered. However, on the other hand, a driving mechanism such as the motor 15 for rotation with respect to the fixed-side rotary tool 70 can be omitted, or the fixed-side magnet unit 71 is made to sufficiently approach (may be brought into contact with) the workpiece 100 to face the workpiece 100. There is an advantage that the interval between the magnet units 71 can be further reduced.

  As described above with respect to the present embodiment and the modifications thereof, according to the joining apparatus 1, the rotary tool 70 is disposed only around the joint portion to which the adhesive 102 of the workpiece 100 is applied, and the magnet unit is rotated by rotating it. The adhesive 102 can be cured or semi-cured simply by changing the magnetic field by 71. Therefore, a large heat treatment furnace or the like that accommodates the entire workpiece 100 is not required. In addition, since the workpiece 100 is directly heated by the induced current, energy loss is less than that of the conventional method using radiant heat, and it can be cured or semi-cured in a short time. That is, according to this embodiment, the adhesive can be efficiently cured or semi-cured in the joining step using the thermosetting adhesive without requiring a large amount of equipment.

  Further, the joining apparatus 1 includes a plurality of magnets (three N-arranged magnets 71 a and three S-arranged magnets 71 b) so that different polarities are alternately arranged in the direction intersecting with the overlapping direction of the metal members 101 and 103. Is mounted on a rotary tool 70 (magnetic field changing means) having a rotation axis substantially parallel to the superimposing direction, and the rotary tool 70 is positioned in the vicinity of the joint portion of the workpiece 100. Thus, the magnetic field can be easily changed with a simple structure. Further, the heating temperature can be easily adjusted by controlling the distance between the rotary tool 70 and the workpiece 100 and the rotational speed of the rotary tool 70.

  Moreover, since the pair of rotary tools 70 (magnet unit 71) are arranged to face each other with the workpiece 100 interposed therebetween and are configured to rotate at least one of them, the magnetic flux 80 penetrates the workpiece 100 by the pair of magnet units 71. The induced current can be generated in the workpiece 100 by changing the magnetic flux density while maintaining the above. Accordingly, the temperature of the joint can be increased more reliably and efficiently.

  In addition, the robot 40 (movement control means) that moves the rotary tool 70 at least in the direction intersecting the rotation shaft 73 is provided, and the heat curing of the adhesive 102 is promoted continuously or intermittently along the movement trajectory. Therefore, even if the joining range (in this embodiment, the application length of the adhesive 102 and the interval between the two adhesives 102) is wide, there is no need to use a rotary tool that covers the entire area, and the equipment can be more It can be made compact.

  Then, by using the highly versatile robot 40 as the movement control means for moving the rotary tool 70, the rotary tool 70 can be easily moved freely, and the adaptability flexibility as the joining device 1 is enhanced.

  Next, a second embodiment according to the present invention will be described. FIG. 10 is a schematic configuration diagram of a metal member bonding apparatus 1a according to a second embodiment of the present invention. In FIG. 10 and subsequent drawings, members having the same or similar functions as those in the first embodiment are denoted by the same reference numerals, and redundant description thereof is omitted.

  The joining apparatus 1a includes a joining gun 10a and a robot 40 including the joining gun 10a on the wrist as main components.

  The joining gun 10a has the same configuration as the one joining gun 10a constituting the joining gun unit 10 shown in FIG. However, instead of the rotary tool 70, a rotary tool 70a (detailed structure will be described later) is attached to the tip. An L-shaped arm 12 extends from the attachment box 11 of the joining gun unit 10, and a cylindrical receiving tool 98 is provided at the tip thereof. The receiving tool 98 is provided so as to face the same axis as the rotary tool 70a.

  The configuration of the robot 40 that moves the bonding gun 10a is the same as that of the first embodiment, and the control unit 50a performs drive control and movement control for one bonding gun 10a.

  FIG. 11 is an explanatory view of the joining process by the joining apparatus 1a. First, the structure of the rotary tool 70a will be described with reference to the upper left figure. The rotary tool 70a includes a rotary shaft 73, a disc portion 74, and a magnet unit 71 similar to those of the rotary tool 70 of the first embodiment. Further, a processing part 91 and a pin part 93 are provided.

  The processing portion 91 is a substantially columnar member provided coaxially and integrally with the rotation shaft 73. The front edge of the processing portion 91 is a shoulder portion 92. The tip surface of the processing portion 91 facing the workpiece 100 is a flat or shallow mortar-shaped surface with a slightly depressed center. A small-diameter columnar pin portion 93 that protrudes further toward the distal end side is provided at the center of the distal end surface.

  Next, the joining process by the joining apparatus 1a of this embodiment is demonstrated, referring FIG. As a material of the workpiece 100 (metal members 101, 103) of the present embodiment, for example, an aluminum alloy plate is suitable. First, the process of applying the adhesive 102 to the metal member 101 and overlaying the metal member 103 thereon is the same as in the first embodiment (shown in the upper and middle stages of FIG. 7). For the sake of convenience, the thickness of the adhesive 102 is exaggerated from the actual one.

  Then, while rotating the rotating shaft 73 (arrow A1), the rotating tool 70a and the receiving tool 98 are brought close to each other so as to sandwich the joint portion of the workpiece 100 (arrows A5 and A6). The rotary tool 70a is lowered by driving the elevating motor 14, and the receiver 98 is lowered (closed to the workpiece 100) by moving the entire joining gun 10a by the robot 40.

  In this embodiment, the magnet unit 71 is disposed only on one side of the workpiece 100. Accordingly, the magnetic field is generated by the three N-arranged magnets 71 a and the three S-arranged magnets 71 b that constitute the magnet unit 71. That is, an arch-shaped magnetic flux is generated mainly between the adjacent N-arranged magnet 71a and S-arranged magnet 71b. The magnetic field changes with the rotation of the rotary tool 70a. As the rotary tool 70a is brought closer to the workpiece 100, the change in the magnetic field acts on the workpiece 100 to generate an induced current and generate heat. Therefore, the effect of promoting the curing of the adhesive 102 can be obtained as in the first embodiment. Moreover, the effect of reducing the clearance gap between the metal member 101 and the metal member 103 by magnetic force is also acquired.

  Subsequently, in this embodiment, the rotary tool 70a and the receiving tool 98 are further brought closer to each other. Then, the receiving tool 98 is brought into contact with the metal member 101, and the processing portion 91 is brought into contact with the metal member 103, and further lowered and pressurized (upper right in FIG. 11). At this time, first, the thin pin portion 93 comes into contact with the metal member 103 before the shoulder portion 92, whereby the rotary tool 70a is positioned with a small frictional resistance, and the rotational runout is suppressed.

  By pressing the workpiece 100 while rotating the processing portion 91, frictional heat is generated in addition to the heat generated by the induced current, so that the workpiece 100 is further heated. Accordingly, the curing of the adhesive 102 is further promoted. Moreover, the workpiece | work 100 softens with those heat.

  Subsequently, the rotary tool 70a is further lowered and pressurized until the pin portion 93 is inserted into the metal member 101 (lower right in FIG. 11). As a result, the frictional heat further increases, and the softening of the workpiece 100 is promoted to cause plastic flow (the temperature at this time is about 400 ° C.). The metal member 101 and the metal member 103 are also joined to each other by this plastic flow. Further, the adhesive 102 is extruded to the periphery, and curing is promoted while increasing the bonding area.

  When the pressing for a predetermined period (about 0.5 to 2.5 s) is completed, the rotary tool 70a and the receiving tool 98 are separated from the workpiece 100 (arrows A7 and A8) as shown in the lower left of FIG.

  As described above, according to the bonding apparatus 1a of the present embodiment, in addition to the heat generated by the induced current, the frictional heat generated by pushing the processed portion 91 can be used. 102 can be cured. Further, the joining of the metal member 101 and the metal member 103 can depend not only on the adhesive 102 but also on joining by plastic flow. Therefore, for example, it is possible to reduce the share of the bonding force of the adhesive 102 with respect to the bonding force required for preventing misalignment (temporary fixing). That is, it can be expected that the degree of semi-curing required for the adhesive 102 is reduced.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to said each embodiment, It can change suitably in a claim.

  For example, although the magnet unit 71 of each said embodiment uses a total of six magnets (71a, 71b), the number is not limited and may be more or less than that. .

  The magnet used for generating the magnetic field is not limited to a permanent magnet, and an electromagnet may be used. When an electromagnet is used, as a means for changing the magnetic field, the electromagnet itself may be moved (including rotation) as in this embodiment, or the magnetic field may be changed by changing the current supplied to the electromagnet. good.

  Further, the movement of the magnet is not necessarily a rotational movement, and may be caused to reciprocate linearly using an appropriate mechanism.

  In the second embodiment, a magnet unit 71 may also be provided on the support 98 side so that the magnetic flux penetrates the workpiece 100 as in the first embodiment. At that time, the magnet unit 71 may be fixed integrally with the receiving tool 98, or may be rotated in the same direction or in the opposite direction to the rotary tool 70a.

  In the second embodiment, the metal member 101 and the metal member 103 may be steel plates. However, in that case, since the temperature at the time of plastic flow is about 800 ° C., it is necessary to pay attention to the heat resistance of the adhesive 102.

It is a schematic block diagram of the joining apparatus of the metal member which concerns on 1st Embodiment of this invention. It is a front view of the joining gun shown in FIG. It is a side view of the joining gun shown in FIG. It is sectional drawing which shows the internal structure of the main body case shown in FIG. It is the VV sectional view taken on the line of FIG. It is structure explanatory drawing of the rotary tool shown in FIG. It is a schematic diagram which shows the joining process of the metal member using an adhesive agent. It is explanatory drawing which shows the modification about rotation operation | movement of a rotary tool. It is explanatory drawing which shows another modification about rotation operation | movement of a rotary tool. It is a schematic block diagram of the joining apparatus of the metal member which concerns on 2nd Embodiment of this invention. It is explanatory drawing of the joining process by the joining apparatus shown in FIG.

Explanation of symbols

1 (Metal member) joining device 10a Joining gun (driving means)
40 Robot (movement control means)
70, 70a Rotary tool (magnetic field changing means)
71 Magnet unit 71a (N arrangement) Magnet 71b (S arrangement) Magnet 91 Processing part

Claims (13)

A method of joining by interposing a thermosetting adhesive between a plurality of stacked metal members,
Generate a magnetic field by a magnet at the joint of the metal member,
An induced current is generated in the metal member by changing the magnetic field,
A method for joining metal members, wherein heat curing of the thermosetting adhesive is promoted by heat generation of the metal members by the induced current. Preparing a magnet unit in which different polarities are alternately arranged in a direction intersecting with the overlapping direction of the metal members,
2. The method of joining metal members according to claim 1, wherein the magnetic field is changed by moving the magnet unit in the arrangement direction of the magnets.   3. The method of joining metal members according to claim 2, wherein the pair of magnet units are arranged opposite to each other with the joint portion interposed therebetween, and the magnetic field is changed by moving at least one of the magnet units. . The magnet unit is attached to a rotary tool having a rotation axis substantially parallel to the overlapping direction of the metal members,
4. The method for joining metal members according to claim 2, wherein the magnet unit is moved by positioning the rotary tool in the vicinity of the joint portion of the metal members and rotating the rotary tool. Provided with a processing portion at the tip of the rotary tool facing the metal member,
While rotating the rotary tool, the processed portion is pushed into the metal member to generate frictional heat, and the metal member is softened by the frictional heat and the heat generated by the induced current to cause plastic flow, and joined. The method for joining metal members according to claim 4, wherein the heat curing of the thermosetting adhesive is accelerated. The joint part of the metal member is provided in a wider range than the rotation trajectory of the rotary tool,
5. The rotary tool is moved within a range where the joint is spread, and the heat curing of the thermosetting adhesive is promoted continuously or intermittently along the movement trajectory. 5. The method for joining metal members according to 5. An apparatus for joining by joining a thermosetting adhesive between a plurality of stacked metal members,
A magnet for generating a magnetic field at the joint of the metal member;
Magnetic field changing means for generating an induced current in the metal member by changing the magnetic field,
An apparatus for joining metal members, wherein heat curing of the thermosetting adhesive is promoted by heat generation of the metal members by the induced current. A magnet unit in which a plurality of magnets are arranged so that different polarities are alternately arranged in a direction intersecting with the overlapping direction of the metal members,
8. The apparatus for joining metal members according to claim 7, wherein the magnetic field changing means moves the magnet unit in the direction in which the magnets are arranged. A pair of the magnet units are arranged opposite to each other with the joint portion interposed therebetween,
9. The apparatus for joining metal members according to claim 8, wherein the magnetic field changing means moves at least one of the magnet units. The magnetic field changing means is a rotary tool having a rotation axis substantially parallel to the overlapping direction of the metal members and having the magnet unit attached thereto,
10. The metal member joining apparatus according to claim 8 or 9, wherein the magnet unit is moved by positioning the rotating tool in the vicinity of the joining portion of the metal member and rotating the rotating tool. The rotary tool includes a processing portion at a tip portion facing the metal member,
While rotating the rotary tool, the processed portion is pushed into the metal member to generate frictional heat, and the metal member is softened by the frictional heat and the heat generated by the induced current to cause plastic flow, and joined. The metal member bonding apparatus according to claim 10, wherein the heat curing of the thermosetting adhesive is accelerated. A movement control means for moving the rotating tool at least in the direction intersecting the rotation axis;
The movement control means moves the rotary tool along a range where the joint extends, and continuously or intermittently promotes heat curing of the thermosetting adhesive along the movement trajectory. The metal member joining apparatus according to claim 10 or 11, characterized in that:   13. The apparatus for joining metal members according to claim 12, wherein the movement control means is a robot having the rotary tool mounted on the tip and a drive means for rotationally driving the rotary tool.

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