JP2022122360A - Joining device - Google Patents

Abstract

To efficiently cool an upper electrode.SOLUTION: A joining device includes a first electrode 101, a second electrode 102, a power source 103, and a pressure application mechanism 104. A welding device includes a position fixing mechanism 112 that fixes a position of a button component 131 in a direction perpendicular to an axial direction of a shaft portion 131b. The position fixing mechanism 112 is formed on a first electrode 101. For example, the position fixing mechanism 112 is a projection formed on a first contact surface 111.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to a joining apparatus for joining a structure made of a different material such as aluminum to a structure made of steel.

High strength and light weight are required for parts (body parts) that constitute a vehicle. For this reason, as materials for forming parts, for example, high-strength steel, aluminum materials, and composite members in which high-strength steel and aluminum materials are integrated are used. In joining dissimilar materials such as these, for example, the shank of a rivet (button part) is inserted by pushing it into an aluminum plate without a hole, and an opening is formed in the aluminum plate in advance, and this The shaft of the rivet is fitted into the opening, and then the tip of the shaft and the steel plate are welded (crimped) (see Patent Document 1).

For example, as shown in FIG. 6A, first, the head of the button component 301 is brought into contact with the lower end surface of the upper electrode 311 of the welding device that performs resistance spot welding. The welding device has a lower electrode 312 arranged below the upper electrode 311 so as to face the upper electrode 311 . Next, the steel plate 302 and the aluminum plate 303 that are stacked are moved so that the welded portion is positioned below the button component 301 . As a result, the welded portion is placed between the lower electrode 312 and the button component 301 . Next, the upper electrode 311 is lowered toward the lower electrode 312 side, and the head portion of the button component 301 is brought into contact with the welded portion of the aluminum plate 303 .

Next, the upper electrode 311 is further lowered to the lower electrode 312 side, and as shown in FIG. , the tip of the button component 301 is brought into contact with the steel plate 302 . By lowering the upper electrode 311 and applying a force along the axial direction of the shaft of the button component 301 , the tip of the button component 301 is pushed in from the surface side of the aluminum plate 303 , and the tip of the shaft is pressed against the steel plate 302 . abut.

Next, by energizing the upper electrode 311 and the lower electrode 312 in contact with the steel plate 302, as shown in FIG. Weld by welding. At this time, while the tip of the button component 301 is in contact with the steel plate 302 , pressure is applied to the button component 301 by the upper electrode 311 while the tip and the steel plate 302 are welded by resistance spot welding.

By this welding, a nugget 304 is formed between the tip of the button part 301 and the steel plate 302 by melting and solidifying them, and the tip is deformed from the tapered shape. As a result, the front end of the button component 301 is welded to the steel plate 302, and the steel plate 302 and the aluminum plate 303 are joined together.

Here, in so-called mass production, the welding described above is performed continuously. When the welding described above is continuously performed, firstly, the button part is supplied to the lower end surface of the upper electrode, secondly, the supplied button part is fixed to the lower end surface of the upper electrode, and thirdly, the plate to be welded is The movement of the member and, fourth, the welding operation described above will be repeated. The above-described supply and fixing of the button part can also be performed after the welded portion of the plate member is arranged between the upper electrode and the lower electrode.

Generally, in this type of bonding apparatus, the upper electrode is pushed down toward the lower electrode so that the tip of the button part is pushed into an aluminum plate or the like. It has a mechanism for fixing the lower electrode and the like for receiving the pressure of . In such a configuration, it is not easy to move the pair of upper and lower electrodes. In this case, by fixing the position of the pair of the upper electrode and the lower electrode and moving the plate member to be joined, the joint can be arranged between the upper electrode and the lower electrode.

By the way, when pushing the button component with the upper electrode as described above, for example, the pushing is performed after the button component is picked up by the upper electrode. Suction is generally used to pick up such button parts. The upper electrode picks up the head portion of the button component having a substantially T-shaped axial cross section by suction. According to such pick-up by suction, it is possible to suppress displacement of the button component in the plane direction of the plate member with respect to the welded portion, depending on the strength of the suction. If the position of the button part fixed to the lower end face of the upper electrode is displaced, there may be a case where the force along the axial direction of the shaft part of the button part cannot be applied, and the shaft part of the button part thrusts obliquely. problems such as For this reason, it is important to fix the button component to the lower end surface of the upper electrode so as not to cause misalignment. According to the pick-up by adsorption, it is possible to prevent the positional deviation as described above by controlling the force of adsorption.

On the other hand, cooling of the upper electrode is important, for example, for the formation of the nuggets mentioned above and for the rapid execution of continuous welds. For example, the tip of a button part and a steel plate are welded by resistance spot welding to form a nugget, and then cooled appropriately to form a nugget with a desired size and high joint strength. important. For this purpose, it is effective, for example, to cool the upper electrode after energizing and heating it for a desired time. In addition, in order to prevent heating before the tip of the button part and the steel plate come into contact with each other, during continuous welding, the upper electrode must be sufficiently deep before the electric heating of each welding process. It is important that the

JP 2015-062911 A

As for the cooling of the upper electrode described above, there is a cooling mechanism in which a pipe for flowing a cooling medium is provided in the upper electrode and a cooling medium such as water is flowed through the pipe. However, as described above, when the upper electrode is provided with an attraction mechanism for attracting the button component to the upper electrode, it is not easy to provide cooling pipes or the like in the upper electrode. In this case, it is conceivable to use a cooling mechanism such as blowing cold air from around the electrode, but in this case, a complicated mechanism will be provided around the upper electrode, and there may be cases where sufficient cooling cannot be achieved. is not practical because As described above, the conventional technique has a problem that it is not easy to efficiently cool the upper electrode.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to enable efficient cooling of the upper electrode.

The joining device according to the present invention comprises a first part made of steel and a second part made of a material different from the steel, which is superimposed on the first part. By applying a force between a first electrode that contacts the head of a button part made of letter-shaped steel and a second electrode that is arranged on the side of the first part and contacts the first part, the button part is By applying pressure, the shaft of the button component is axially pushed in from the surface side of the second component, the tip of the shaft is brought into contact with the first component, and the tip and the first component are welded by resistance spot welding. a first electrode having a first contact surface with which the head portion of the button part abuts; and a second electrode having a second contact surface with which the first part abuts. and the first electrode and the second electrode are connected to each other, and when the tip of the button part contacts the first part, the first electrode and the second electrode are energized to connect the tip and the first part. a power supply for heating the contact point of the , a pressure mechanism that applies a force between the first electrode and the second electrode so that the distance between the first electrode and the second electrode becomes small, and the first electrode a position fixing mechanism for fixing the position of the button component in the direction perpendicular to the axial direction of the shaft portion, wherein the first contact surface of the first electrode and the second contact surface of the second electrode; are placed facing each other.

In one configuration example of the bonding apparatus, the first electrode is arranged on the ground side with respect to the second electrode.

In one configuration example of the bonding apparatus, the pressure mechanism applies force between the first electrode and the second electrode by pushing up the first electrode toward the second electrode.

In one configuration example of the bonding apparatus, the second electrode is arranged on the ground side with respect to the first electrode, and further includes a gripping mechanism that grips the periphery of the head of the button part and presses the button part against the first electrode. Prepare.

In one configuration example of the bonding apparatus, the pressure mechanism applies force between the first electrode and the second electrode by pressing the first electrode down toward the second electrode.

In one configuration example of the joining apparatus, the position fixing mechanism is a projection formed on the first contact surface.

In one configuration example of the joining device, the position fixing mechanism is arranged around the first contact surface at a position surrounding the head portion of the button component that contacts the first contact surface.

In one configuration example of the joining apparatus, the position fixing mechanism is an annular wall formed around the first contact surface.

In one configuration example of the joining apparatus, the position fixing mechanism is three or more protrusions formed around the first contact surface.

As described above, according to the present invention, the first electrode is provided with a position fixing mechanism for fixing the position of the button component in the direction perpendicular to the axial direction of the shaft portion of the button component. can be cooled efficiently.

FIG. 1 is a configuration diagram showing the configuration of a joining apparatus according to an embodiment of the present invention. FIG. 2A is a configuration diagram showing a partial configuration of the joining device according to the embodiment of the present invention. FIG. 2B is a plan view showing a partial configuration of the joining device according to the embodiment of the present invention; FIG. 2C is a plan view showing a partial configuration of the joining device according to the embodiment of the present invention; FIG. 3A is a plan view showing a partial configuration of the joining device according to the embodiment of the present invention; FIG. 3B is a plan view showing a partial configuration of the joining device according to the embodiment of the present invention; FIG. 4 is a configuration diagram showing the configuration of another joining apparatus according to the embodiment of the present invention. FIG. 5 is a perspective view showing a partial configuration of another joining device according to the embodiment of the present invention. FIG. 6A is an explanatory diagram for explaining the joining method. FIG. 6B is an explanatory diagram for explaining the joining method. FIG. 6C is an explanatory diagram for explaining the joining method.

A joining apparatus according to an embodiment of the present invention will be described below with reference to FIG. This bonding apparatus includes a first electrode 101, a second electrode 102, a power source 103, and a pressure mechanism 104, like a well-known bonding apparatus. This joining device uses a button part 131 to join a first part 132 made of steel to a second part 133 made of a material different from steel (for example, an aluminum alloy). The first part 132 and the second part 133 are plate members, for example.

The first electrode 101 has a first contact surface 111 with which the head portion 131a of the button component 131 contacts. The first contact surface 111 is composed of one plane. For example, the first contact surface 111 can have a size greater than or equal to a range in which the entire head 131a can be accommodated in a plan view. The head 131a is, for example, a circle with a diameter of about 12 mm in plan view. The first abutment surface 111 can be larger than this area. Also, the outer diameter of the first electrode 101 can be larger than the diameter of the first contact surface 111 . For example, the first electrode 101 can have an outer diameter of about 13 mm. Also, the first contact surface 111 can be smaller than the area of the head 131a in plan view. Also, the outer diameter of the first electrode 101 can be smaller than the area of the head 131a in plan view. For example, when the head 131a has a diameter of about 12 mm, the outer shape of the first electrode 101 can be about 8 mm to 11 mm.

The second electrode 102 has a second contact surface 121 against which the first component 132 contacts. The second contact surface 121 is composed of one plane. The first contact surface 111 of the first electrode 101 and the second contact surface 121 of the second electrode 102 are arranged to face each other. The first contact surface 111 and the second contact surface 121 are parallel to each other. Also, in this example, the first electrode 101 is arranged on the ground side with respect to the second electrode 102 .

A power source 103 is connected to the first electrode 101 and the second electrode 102 respectively. When the tip portion 131c of the button part 131 contacts the first part 132, the power source 103 causes the first electrode 101 and the second electrode 102 to be electrically connected. As a result, the contact portion between the tip portion 131c and the first component 132 is electrically heated and welded (resistance spot welding). Welding may be AC welding, DC welding, servo welding, or the like.

The pressure mechanism 104 applies force between the first electrode 101 and the second electrode 102 so that the distance between the first electrode 101 and the second electrode 102 is reduced. In this example, the pressure mechanism 104 applies force between the first electrode 101 and the second electrode 102 by pushing the first electrode 101 toward the second electrode 102 .

By using the bonding apparatus described above, the following well-known bonding can be performed. First, the second part 133 made of a material different from steel is placed on the first part 132 made of steel. The first part 132 and the second part 133 that are arranged in an overlapping manner are moved by a moving device (not shown), and the welding point is arranged at the button part 131 . In this case, the welding point is arranged on the upper part of the button component 131 .

Next, the first electrode 101 abuts on the head portion 131a of a button component 131 made of steel having a substantially T-shaped cross section in the axial direction and comprising a head portion 131a and a shaft portion 131b connected to the head portion 131a; By applying a force between the button part 131 and the second electrode 102 arranged on the side of the part 132 and in contact with the first part 132 , pressure is applied to the button part 131 and the axis of the button part 131 is pushed from the surface side of the second part 133 . The portion 131b is pushed axially. Next, the tip portion 131c of the shaft portion 131b is brought into contact with the first component 132, and the tip portion 131c and the first component 132 are welded by resistance spot welding.

In addition to the configuration described above, the welding device according to the embodiment includes a position fixing mechanism 112 for fixing the position of button component 131 in the direction perpendicular to the axial direction of shaft portion 131b. A position fixing mechanism 112 is formed on the first electrode 101 . For example, the position fixing mechanism 112 is a protrusion formed on the first contact surface 111 .

The shape of the position fixing mechanism 112 can be, for example, a cone or column having a bottom surface of 3 to 4 mm in diameter and a height of 1 to 2 mm. In this case, it is assumed that a concave portion 134 that fits into the position fixing mechanism 112 is formed in the head portion 131a at a position corresponding to the position fixing mechanism 112 using a projection.

For example, the first contact surface 111 and the head 131a have the same shape (area) in a plan view, and a position fixing mechanism 112 is formed by a protrusion in the center of the first contact surface 111. The recess 134 described above is formed in the center of 131a. When the head portion 131a of the button component 131 is placed on the first contact surface 111 and the concave portion 134 is fitted to the position fixing mechanism 112 by the protrusion, Positional deviation of the button component 131 with respect to the first contact surface 111 can be prevented.

2A and 2B, the position fixing mechanism 112a is positioned around the first contact surface 111 so as to surround the head portion 131a of the button component 131 that contacts the first contact surface 111. It can be an annular wall arranged. In this case, the shape in plan view is circular in accordance with the shape of the head 131a, which is circular in plan view. Further, when the head portion 131a that contacts the first contact surface 111 is rectangular in plan view, as shown in FIG. can. In this case, a rectangular shape with rounded corners is also possible.

Further, as shown in FIG. 3A, the position fixing mechanism 112c is arranged around the first contact surface 111 at a position surrounding the head portion 131a of the button component 131 that contacts the first contact surface 111. It is also possible to have three or more protrusions. In this example, it corresponds to the head 131a having a circular shape in plan view. Further, when the head portion 131a that contacts the first contact surface 111 is rectangular in plan view, as shown in FIG. A mechanism 112d may also be provided. It is also possible to make the area of the head of the button component larger than the first contact surface of the first electrode, provide an annular wall around the head, and use this as a position fixing mechanism. In this configuration, when the head portion of the button component is in contact with the first contact surface, the annular wall of the head portion surrounds the first electrode, and the first contact direction is perpendicular to the axial direction. It is possible to prevent the positional deviation of the button component with respect to the contact surface.

According to the above-described embodiment, the button component 131 is supplied to the first contact surface 111, which is the top surface of the first electrode 101. Therefore, a complex fixing mechanism such as an adsorption mechanism is provided to the first electrode 101. No need. Therefore, it becomes easy to provide (incorporate) the first electrode 101 with the liquid-cooled cooling mechanism 113 configured by a pipe for flowing a cooling medium. As described above, according to the embodiment, the first electrode 101 can be efficiently cooled, a desired high bonding strength can be obtained, and continuous welding can be performed during each welding process. It is possible to sufficiently cool the first electrode 101 in the stage prior to conducting heating.

By the way, as shown in FIG. 4, the second electrode 102 can also be arranged on the ground side with respect to the first electrode 101 . In this case, since the first contact surface 111 of the first electrode 101 faces the ground, a grasping mechanism 105 is provided for fixing the button part 131 to the first contact surface 111 . The gripping mechanism 105 grips the periphery of the head portion 131 a of the button component 131 and presses the button component 131 against the first electrode 101 . In this configuration, the pressure mechanism 104 applies force between the first electrode 101 and the second electrode 102 by pressing the first electrode 101 toward the second electrode 102 . Alternatively, the gripping mechanism may use magnetic force. Other configurations are the same as those of the above-described embodiment.

Note that the position fixing mechanism 112 is not limited to a conical shape, and may be an elliptical cone, a quadrangular pyramid, an annular projection, a truncated cone, or the like. Moreover, as shown in FIG. 5, it is also possible to form a cross-shaped projection in plan view.

As described above, according to the present invention, the first electrode is provided with a position fixing mechanism for fixing the position of the button component in the direction perpendicular to the axial direction of the shaft portion of the button component. can be cooled efficiently. According to the present invention, since it is not necessary to provide a complicated mechanism for fixing the button part to the first electrode, the upper electrode can be efficiently cooled, such as liquid cooling using a cooling medium such as water.

It should be noted that the present invention is not limited to the embodiments described above, and many modifications and combinations can be implemented by those skilled in the art within the technical concept of the present invention. It is clear.

DESCRIPTION OF SYMBOLS 101... 1st electrode, 102... 2nd electrode, 103... Power supply, 104... Pressure mechanism, 111... 1st contact surface, 112... Position fixing mechanism, 113... Cooling mechanism, 121... 2nd contact surface, 131 ... button part, 131a... head part, 131b... shaft part, 131c... tip part, 132... first part, 133... second part, 134... concave part.

Claims (9)

A second part made of a material different from steel is superimposed on the first part made of steel,
a first electrode of a button component made of steel having a substantially T-shaped cross section in the axial direction and made of a head and a shaft connected to the head; By applying force between the second electrode and the second electrode that abuts on the first component, pressure is applied to the button component, and the shaft portion of the button component is pushed in the axial direction from the surface side of the second component. ,
A joining device used for carrying out a joining method in which the tip portion of the shaft portion is brought into contact with the first component and the tip portion and the first component are welded by resistance spot welding,
the first electrode having a first contact surface with which the head portion of the button component contacts;
the second electrode having a second contact surface with which the first component contacts;
The first electrode and the second electrode are connected to each other, and when the tip portion of the button part contacts the first part, the first electrode and the second electrode are electrically energized, and the tip is a power supply for heating a contact point between the part and the first part;
a pressure mechanism that applies a force between the first electrode and the second electrode so that the distance between the first electrode and the second electrode is reduced;
a position fixing mechanism formed on the first electrode for fixing the position of the button component in a direction perpendicular to the axial direction of the shaft,
A joining device, wherein a first contact surface of the first electrode and a second contact surface of the second electrode are arranged to face each other. The joining apparatus according to claim 1,
The joining device, wherein the first electrode is arranged on the ground side with respect to the second electrode. The joining apparatus according to claim 2,
The bonding device, wherein the pressure mechanism applies force between the first electrode and the second electrode by pushing up the first electrode toward the second electrode. The joining apparatus according to claim 1,
The second electrode is arranged on the ground side with respect to the first electrode,
A joining device, further comprising a gripping mechanism that grips the periphery of the head of the button component and presses the button component against the first electrode. The joining apparatus according to claim 4,
The bonding device, wherein the pressure mechanism applies force between the first electrode and the second electrode by pressing the first electrode toward the second electrode. In the joining apparatus according to any one of claims 1 to 5,
The joining device, wherein the position fixing mechanism is a projection formed on the first contact surface. In the joining apparatus according to any one of claims 1 to 5,
The joining device, wherein the position fixing mechanism is arranged around the first contact surface at a position surrounding the head portion of the button component that contacts the first contact surface. The joining apparatus according to claim 7,
The joining device, wherein the position fixing mechanism is an annular wall formed around the first contact surface. The joining apparatus according to claim 7,
The joining device, wherein the position fixing mechanism is three or more protrusions formed around the first contact surface.

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