JP2000218384A - Checking devide for laser welding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance checking accuracy in a checking device for laser welding. SOLUTION: With this device, welding conditions of plural metallic plates are checked from a color tone on the other side of plural metallic plate polymers 1, to which lasers are radiated from one side A. On the other side of the polymers 1, whether laser welding is correctly performed or not is checked by a degree of occurrence of a portion where the color tone is changed. In this case, not the condition of a welding mark 7 is checked, but a peripheral portion where the welding mark 7 does not occur is checked. Thereby, checking is stabilized. As a result, checking accuracy of the laser welding condition can be heightened.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser welding inspection apparatus for inspecting, for example, a weld between an internal electrode and a terminal electrode of an electronic component.

[0002]

2. Description of the Related Art The configuration of a conventional laser welding inspection apparatus is as follows. That is, since welding marks by laser welding are exposed on the other side of the polymer of the plurality of metal plates irradiated with laser from one side, light is irradiated on the welding marks and the state is inspected. It was like that.

[0003]

However, the conventional inspection apparatus has a problem that the inspection accuracy is reduced.

[0004] That is, the welding marks formed on the other surface side of the polymer vary greatly in its state due to laser welding, and more specifically, have irregularities on its surface.
Since the irregularities change, the inspection is performed by irradiating the surface with light and reflecting the light, the amount of reflection from the welding mark is not stable, and as a result, the inspection accuracy can be increased. I couldn't.

Accordingly, an object of the present invention is to improve the inspection accuracy of a laser welding state.

[0006]

In order to achieve this object, the present invention is configured to inspect the welding condition of a plurality of metal plates by using the color tone of the other side of the polymer of the metal plate. .

That is, when a laser is irradiated from one surface of a polymer of a plurality of metal plates, welding marks are formed on the other surface of the polymer in the same manner as in the prior art. The color of the weld mark portion is different from that of the outer periphery.

Therefore, in the present invention, whether or not laser welding is properly performed is confirmed by determining how much a portion of the polymer whose color tone has changed on the other surface side. In this case, instead of detecting the state of the welding marks, the outer peripheral portion where no welding marks are formed is inspected, so that the inspection is always stable, and as a result, the inspection of the laser welding state is performed. Accuracy can be increased.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention is characterized in that the plurality of metal plates are irradiated with laser light from one surface side and the welding state of the plurality of metal plates is determined by the color of the other surface side. Is a laser welding inspection device for inspecting the inspection, and the inspection accuracy can be improved.

That is, on the other side of the polymer,
This is to check whether laser welding is performed correctly by checking the extent to which the color tone has changed.In this case, instead of detecting the state of the welding mark, the welding mark is not detected. Since the inspection is performed on the outer peripheral portion that does not occur, the inspection is always stable,
As a result, there is an effect that the inspection accuracy of the laser welding state can be improved.

According to a second aspect of the present invention, there is provided the laser welding inspection apparatus according to the first aspect, wherein the metal plate on the other side of the polymer is formed by plating at least the other side with copper. Since the copper plate is applied to the metal plate on the other side for inspecting the welding state, the color tone peculiar to the copper plating, that is, the red-based color tone is increased in this inspection portion.

[0012] In this case, since the welding mark is significantly different from the red system and is transformed into a white system, the extent to which the color tone of the red system has been reduced can be detected very easily and accurately. As a result, the inspection accuracy can be improved.

According to a third aspect of the present invention, there is provided the laser welding inspection apparatus according to the second aspect, wherein the metal plate is formed of iron and the surface of the iron is plated with copper. In addition, the iron often dissolves and the welding marks often become white.

For this reason, there is a large difference in color tone from the reddish color peculiar to copper plating, and this can be easily and accurately detected by the inspection apparatus to detect a large decrease in the reddish color or the like. And the inspection accuracy can be improved.

According to a fourth aspect of the present invention, the welding condition is inspected based on the amount of a specific color component detected from the other side of the polymer. Inspection of the welding condition based on the amount of a specific color component is very simple and can improve accuracy.

More specifically, if the other side of the polymer is set to a specific color tone, for example, a red color system, the welding condition can be inspected only by how much the red color system has been reduced. This has the effect that this inspection can be performed easily and with high accuracy.

According to a fifth aspect of the present invention, there is provided a laser welding method as set forth in any one of the first to fourth aspects, wherein the polymer comprises a plurality of extraction electrodes extending from the internal electrodes of the electronic component and terminal electrodes surrounding the extraction electrodes. This is an inspection device, and the polymer is composed of the extraction electrode from the internal electrode, which is a forming element of the electronic component, and the terminal electrode, so that the laser welding of the terminal electrode portion of the electronic component can be performed easily and easily. This has the effect that the operation can be performed with high accuracy.

According to a sixth aspect of the present invention, a plurality of terminal electrodes are provided on a hoop material, and each terminal electrode wraps an extraction electrode of an electronic component to form a polymer, and a laser is applied from one surface side of the polymer. The laser welding inspection apparatus according to claim 5, wherein the laser beam is irradiated and welded and continuously supplied to the welding inspection unit by a hoop, and the inspection part is continuously supplied to the welding inspection unit by the hoop. Therefore, it is possible to perform an inspection in a state of high productivity.

An embodiment of the present invention will be described below with reference to the drawings. 1 and 2 are for explaining an embodiment of the present invention, and specifically show an electrolytic capacitor. This electrolytic capacitor has a configuration in which forming elements 1 each having a plurality of internal electrodes are stacked, and the outer surface thereof is covered with a mold resin 2.

Further, in this state, terminal electrodes 3 and 4 are drawn out from both ends of the molding resin 2.

The forming element 1 is formed of, for example, an aluminum foil, and its surface is roughened and then oxidized. The lead electrode portion 1a is coated with a conductive material 5 on the front and back surfaces and a silver paste 6 on the front surface.

As shown in FIG. 3, the terminal electrodes 3 and 4 have a so-called dust-like shape, and the extraction electrode portions 1a of the plurality of forming elements 1 are provided with the holding portions 3a of the terminal electrodes 3 in FIG.
And conduction is achieved by applying a silver paste or the like.

On the other hand, in the portion of the terminal electrode 4, after the extraction electrode portion 1b of the forming element 1 is overlapped,
As shown in FIG. 4A, it is folded back so as to wrap around from both sides. At point A in FIG. 4A, laser irradiation is performed from the upper surface side for welding.

As a result, the terminal electrode 4 and the portion of the extraction electrode portion 1b included therein are integrated in a molten state. At this time, a welding mark 7 is formed on the lower surface side of the terminal electrode 4 as shown in FIG.

The terminal electrode 4 is made of iron or the like, and has a surface plated with copper.
Therefore, the surface is in a red color tone characteristic of copper.

If laser welding is performed at the point A in FIG. 4A in such a state, the terminal electrode 4 at the weld mark 7 will change color to white.

In this case, laser welding is performed as shown in FIG.
As shown in FIG. 2, since the upper side is heated, the upper side of the terminal electrode 4 is heated and the color tone of the upper side of the terminal electrode 4 is mostly changed from reddish. Since there is a sufficient distance after being bent largely left and right, only the portion of the welding mark 7 on the back surface side of the terminal electrode 4 changes to white.

For this reason, as shown in FIG. 5, light is radiated from the back side by a fluorescent lamp 8 as an irradiation source,
In this state, when the color tone is determined by the color camera 9 which is a color tone recognition device, basically, in the red color tone state on the back surface side of the terminal electrode 4 (7a in FIG. ), Only the portion of the welding mark 7 is detected as a white color.

In this case, in the present embodiment, the image processing mechanism 11 determines how much the red color on the back side of the terminal electrode 4 has been reduced by the color extracting mechanism 10.
Is determined.

That is, before the laser welding is performed, the rear surface of the terminal electrode 4 has a reddish color peculiar to copper on the front surface.
Only the part will be transformed into white.

Since the red component has decreased in the part of the inspection area 7a which has changed to the white color, it can be said that the welding has been reliably performed by the fact that the quantity and the red color have decreased from the initial state. That is to detect that.

In the case of simply examining the extent to which the red color has been reduced, the inspection accuracy is significantly higher than that of what color system has been changed by looking at the weld mark. Become.

That is, although the portion of the welding mark 7 has been described in the prior art, this portion is uneven due to the influence of laser welding, and its surface state and color tone become indefinite. It is very difficult to check whether the welding has been performed correctly by looking at, and in the embodiment of the present invention, this part is how much the original red system has changed. Attention is paid only to the fact that the inspection accuracy becomes extremely high.

[0034]

As described above, according to the laser welding inspection apparatus of the present invention, the welding state of the plurality of metal plates is controlled by the color tone of the other surface of the polymer of the plurality of metal plates irradiated with laser from one surface. On the other side of the polymer, the extent to which the color tone has changed on the other side of the polymer is checked to determine whether laser welding is performed correctly, In this case, instead of detecting the state of the welding marks, the outer peripheral portion where no welding marks are formed is inspected, so that the inspection is always stable, and as a result, the inspection of the laser welding state is performed. This has the effect that the accuracy can be made extremely high.

[Brief description of the drawings]

FIG. 1 is a partially cutaway perspective view of an electrolytic capacitor for describing an embodiment of the present invention.

FIG. 2 is a plan view of the internal electrode.

FIG. 3 is a perspective view of the terminal electrode.

4 (a) and 4 (b) are configuration diagrams for explaining the laser welding and the inspection thereof.

FIG. 5 is a block diagram for explaining an inspection state thereof;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Forming element 1a, 1b Extraction electrode part 2 Mold resin 3, 4 Terminal electrode 3a Holding part 5 Conductive material 6 Silver paste 7 Welding mark 8 Fluorescent lamp 9 Color camera 10 Color extraction mechanism 11 Image processing mechanism

Claims (6)

[Claims] 1. A laser welding inspection apparatus for inspecting a welding state of a plurality of metal plates by using a color of another surface of a polymer of the plurality of metal plates irradiated with laser from one surface side. 2. The laser welding inspection apparatus according to claim 1, wherein the metal plate on the other surface side of the polymer is formed by plating at least the other surface side with copper. 3. The laser welding inspection apparatus according to claim 2, wherein the metal plate is formed of iron, and the surface of the iron is plated with copper. 4. The laser welding inspection apparatus according to claim 1, wherein a welding state is inspected based on an amount of a specific color component detected from the other side of the polymer. 5. The laser welding inspection apparatus according to claim 1, wherein the polymer comprises a plurality of extraction electrodes from the internal electrodes of the electronic component and terminal electrodes surrounding the extraction electrodes. 6. A method in which a plurality of terminal electrodes are provided on a hoop material, each of the terminal electrodes wraps an extraction electrode of an electronic component to form a polymer, and the polymer is welded by irradiating a laser from one side of the polymer. 6. The laser welding inspection apparatus according to claim 5, wherein the laser beam is continuously supplied to the welding inspection unit by a hoop.