JP3858500B2 - Laser welding inspection equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a laser welding inspection apparatus that inspects a welded portion between an internal electrode and a terminal electrode in an electronic component, for example.
[0002]
[Prior art]
The configuration of the conventional laser welding inspection apparatus is as follows. That is, since the welding mark by laser welding is exposed on the other side of the polymer of the plurality of metal plates irradiated with laser from one side, this welding mark part is irradiated with light and the state is inspected. It was like that.
[0003]
[Problems to be solved by the invention]
However, the conventional inspection apparatus has a problem that the inspection accuracy is lowered.
[0004]
That is, the welding mark generated on the other surface side of the polymer is greatly changed in its state by laser welding. Specifically, the surface has unevenness, and this unevenness state changes. In the case where the inspection is performed by irradiating the surface with light and reflecting it, the amount of reflection from the welding mark is not stable, and as a result, the inspection accuracy cannot be increased.
[0005]
Accordingly, the present invention aims to increase the inspection accuracy of the laser welding state.
[0006]
[Means for Solving the Problems]
And in order to achieve this objective, this invention is set as the structure which test | inspects the welding state in a some metal plate by the color tone of the other surface side of the polymer of a metal plate.
[0007]
That is, when laser is irradiated from one side of a polymer of a plurality of metal plates, welding marks are generated on the other side of the polymer as in the conventional case. The color of the portion changes from the outer periphery.
[0008]
Therefore, in the present invention, on the other side of the polymer, it is confirmed whether or not laser welding is correctly performed by checking how much the color-changed portion is generated. Since it detects changes in the color tone of the inspection area, the inspection is always stable, and as a result, the inspection accuracy of the laser welding state can be increased.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
According to the first aspect of the present invention, a plurality of forming elements each having an internal electrode are stacked, and both ends thereof are wrapped with a metal plate, and then irradiated with laser from one surface side of the metal plate to A laser welding inspection apparatus for inspecting a weld portion of a polymer of a metal plate formed by welding the forming element and the metal plate, the irradiation source for irradiating light to the other surface side of the polymer, and the weight A color camera for recognizing the color tone of the reflected light from the merge, a color extraction mechanism for extracting a predetermined color tone from the video signal of the color camera, and an image processing for determining a change in the predetermined color tone from the video signal from the color extraction mechanism A laser welding inspection apparatus that inspects the welding state by a change in color tone of the inspection area on the lower surface side of the polymer, that is, on the other surface side of the polymer, Around Because it is intended to detect a change in color tone, always in the inspection it is stable, provides the effect that it is possible to improve the inspection accuracy of the laser welding condition as a result.
[0011]
The invention according to claim 2 is the laser welding inspection apparatus according to claim 1, wherein the metal plate on the other surface side of the polymer is formed by copper plating on at least the other surface side, By performing copper plating on the metal plate on the other surface side for inspecting the welded state, the color tone peculiar to copper plating, that is, the color tone of the red color system is large in this inspection portion.
[0012]
In this case, the welding mark is very different from this red color system and changes to white color. Therefore, how much the color tone of the red color system has been reduced can be detected very easily and accurately. As a result, there is an effect that the inspection accuracy can be improved.
[0013]
The invention according to claim 3 is the laser welding inspection apparatus according to claim 2 in which the metal plate is formed of iron and the surface of the iron is plated with copper. Often begins to melt and the resulting weld marks are white.
[0014]
For this reason, there is a large difference in color tone from the red color peculiar to copper mesh, and this can be detected easily and accurately by the inspection device that a significant decrease in the color of the red color etc. There exists an effect | action that a test | inspection precision can be raised.
[0015]
Invention of Claim 4 is set as the laser welding inspection apparatus as described in any one of Claims 1-3 which test | inspects a welding state with the quantity of the specific color component detected from the other surface side of a polymer. Therefore, inspecting the welding state by the amount of a specific color component is very simple and can improve accuracy.
[0016]
Specifically, if the other side of the polymer is set to a specific color tone, for example, a red color system, the welding state can be inspected only by how much the red color system has been reduced. However, it is easy and can be performed with high accuracy.
[0017]
The invention according to claim 5 is a laser welding inspection apparatus according to any one of claims 1 to 4, wherein the polymer comprises a plurality of extraction electrodes from the internal electrode of the electronic component and a terminal electrode that wraps the polymer. In this way, the polymer is composed of the lead electrode and the terminal electrode from the internal electrode, which is an element for forming the electronic component, so that the laser welding of the terminal electrode portion in the electronic component can be performed easily and accurately. There is an effect that it becomes possible to.
[0018]
In the invention according to claim 6, a plurality of terminal electrodes are provided on the hoop material, each terminal electrode encloses an extraction electrode of an electronic component, and a polymer is formed. A laser is irradiated from one side of the polymer. The laser welding inspection apparatus according to claim 5, wherein the welded part is continuously supplied to the welding inspection part by a hoop, and the inspection part is continuously supplied to the welding inspection part by the hoop. There exists an effect | action that it can test | inspect in a state with high productivity.
[0019]
Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 and FIG. 2 are for explaining an embodiment of the present invention, and specifically show an electrolytic capacitor. This electrolytic capacitor has a configuration in which a forming element 1 having a plurality of internal electrodes is laminated, and its outer surface is packaged with a mold resin 2.
[0020]
Further, in this state, terminal electrodes 3 and 4 are drawn out at both ends of the mold resin 2.
[0021]
The forming element 1 is formed of, for example, an aluminum foil, and the surface thereof is roughened and then oxidized. The lead electrode portion 1a is coated with a conductive material 5 on its front and back surfaces and a silver paste 6 on its surface.
[0022]
As shown in FIG. 3, the terminal electrodes 3 and 4 are in a so-called dust-like shape, and the lead electrode portions 1a of the plurality of forming elements 1 are held by the holding portions 3a of the terminal electrodes 3 in FIG. Conduction is achieved by application.
[0023]
On the other hand, in the portion of the terminal electrode 4, after the extraction electrode portion 1 b of the forming element 1 is overlapped, it is folded back so as to be wrapped from both sides as shown in FIG. 4 (a), and at the point A in FIG. Laser irradiation is performed for welding from the side.
[0024]
As a result, the terminal electrode 4 and the lead 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.
[0025]
The terminal electrode 4 is made of an iron material or the like, and has a surface plated with copper. Therefore, the surface has a red color tone characteristic unique to copper.
[0026]
When laser welding is performed at point A in FIG. 4A in such a state, the terminal electrode 4 in the weld mark 7 portion is changed to a white color.
[0027]
In this case, as shown in FIG. 4A, laser welding is performed at two points on the upper surface side, so that the upper side is particularly heated and the color tone of the upper surface side of the terminal electrode 4 is mostly changed from red. However, since the back surface side is largely curved from the front surface side to the left and right, it has a sufficient distance to wrap around. As a result, on the back surface side of the terminal electrode 4, only the portion of the welding mark 7 is present. The color will change to white.
[0028]
For this reason, as shown in FIG. 5, when light is emitted from the back side of the fluorescent lamp 8 as an irradiation source and the color camera 9 which is a color recognition device in this state determines the color tone, basically, In the red color tone state on the back surface side of the terminal electrode 4 (7a in FIG. 4B is the inspection area), only the portion of the welding mark 7 is detected as white.
[0029]
In this case, in the present embodiment, the image processing mechanism 11 determines how much the red color on the back surface side of the terminal electrode 4 has been reduced by the color extraction mechanism 10.
[0030]
That is, before laser welding is performed, the back side of the terminal electrode 4 has a red color characteristic of copper, but as a result of the laser welding, only the portion of the weld mark 7 becomes white color. It will be altered.
[0031]
Since the red component has decreased in the inspection area 7a at the portion that has changed to the white system, it is detected that the welding has been performed reliably when the red system has decreased by a certain amount from the initial state. To do.
[0032]
Thus, what inspects how much the red-colored system has simply decreased is markedly higher in inspection accuracy than what the color system has changed by looking at the weld mark portion.
[0033]
That is, although the portion of the weld mark 7 has been described in the prior art, this portion is uneven due to the effect of laser welding, and the surface state and color tone become indefinite. It is very difficult to inspect whether the welding has been performed correctly, and in the embodiment of the present invention, this part depends on how much the original red system has changed. In this case, the inspection accuracy is extremely increased.
[0034]
【The invention's effect】
As described above, the laser welding inspection apparatus of the present invention includes an irradiation source for irradiating the other surface side of the polymer irradiated with laser from one surface side , a color camera for recognizing the color of reflected light from the other surface side, and A laser welding inspection apparatus comprising: a color extraction mechanism that extracts a predetermined color tone from a video signal of a color camera; and an image processing mechanism that determines a change in a predetermined color tone from the video signal from the color extraction mechanism. Because the welding state can be detected by the change in the color of the inspection area on the back side of the surface to be irradiated, the inspection is always stable without being affected by the surface condition of the weld mark. The laser welding state inspection accuracy can be extremely increased.
[Brief description of the drawings]
FIG. 1 is a partially cutaway perspective view of an electrolytic capacitor for explaining 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. (A) and (b) are block diagrams for explaining the laser welding and the inspection thereof. FIG. 5 is a block diagram for explaining the inspection state.
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)

A plurality of forming elements having internal electrodes are laminated, and both ends thereof are wrapped with a metal plate, and then laser is irradiated from one side of the metal plate to weld the plurality of forming elements and the metal plate. A laser welding inspection apparatus for inspecting a welded portion of a polymer of a metal plate, an irradiation source for irradiating light to the other side of the polymer, and a color camera for recognizing the color of reflected light from the polymer; A color extraction mechanism for extracting a predetermined color tone from the video signal of the color camera, and an image processing mechanism for determining a change in the predetermined color tone from the video signal from the color extraction mechanism. Laser welding inspection device that inspects the welding state by changing the color tone of the inspection area.   The laser welding inspection apparatus according to claim 1, wherein the metal plate on the other surface side of the polymer is formed by copper plating on at least the other surface side.   The laser welding inspection apparatus according to claim 2, wherein the metal plate is made of iron and the surface of the iron is plated with copper.   The laser welding inspection apparatus according to any one of claims 1 to 3, wherein a welding state is inspected by an amount of a specific color component detected from the other surface side of the polymer.   The laser welding inspection apparatus according to any one of claims 1 to 4, wherein the polymer includes a plurality of extraction electrodes from an internal electrode of the electronic component and a terminal electrode that wraps the plurality of extraction electrodes.   A plurality of terminal electrodes are provided on a hoop material, and each terminal electrode encloses an extraction electrode of an electronic component to form a polymer, and a laser is irradiated from one side of the polymer and welded to form a polymer. The laser welding inspection apparatus according to claim 5, wherein the laser welding inspection apparatus is supplied to a welding inspection unit.

Images