JPH0415882B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is applicable to materials such as IC lead frame materials.
A device installed in the manufacturing process or inspection process of a partially clad material in which another metal strip is overlapped in the longitudinal direction of a part of a metal strip in the width direction, and used to measure the width of the substrate part and/or clad part. Regarding.

[Prior art]

Conventionally, a cladding material is made by overlapping a part of a metal strip serving as a substrate in the width direction with another metal strip in the longitudinal direction of the substrate strip as shown in Fig. 2. The width of each part shown in It was calculated based on the signal width of the signal.

Fig. 10 is a waveform diagram showing the imaging signal, and in the figure, A, B, and C correspond to each part of A, B, and C in Fig. 2, and the clad part A is compared to the substrate parts A and C. The brightness level is increasing, and there are variations in the brightness level even in the same area.

In addition, Fig. 11 a and b show two types (for the substrate part and for the clad part), which are shown by broken lines in Fig. 10.
This is a waveform diagram obtained by binarizing at a level of The total width of the board part and the width of the cladding part A were measured.

[Problem that the invention seeks to solve]

However, in the width measurement as described above, due to variations in irradiation conditions such as the angle of the light source to the cladding material, or variations in manufacturing conditions, variations in the brightness level of the reflected light occur from strip to strip or in the longitudinal direction of the strip, for example, as shown in FIG. This is a waveform diagram of the luminance signal. In the binarized waveform diagram obtained by binarizing this, the boundary between the substrate part and the cladding part is not clear, and it is possible to misidentify the substrate part as the cladding part (or vice versa) and obtain an accurate width measurement value. The downside is that there are some things that aren't there.

Furthermore, it is necessary to set two types of binarization levels for the substrate section and the cladding section, which is a troublesome task.

Furthermore, the sensitivity in the width direction of the cladding material varies depending on the angle of inclination of the image sensor camera with respect to the cladding material, which may cause measurement errors, but no countermeasures have been taken for this.

[Means for solving problems]

The present invention has been made in view of the above circumstances, and is capable of differentiating an imaging signal representing the brightness of reflected light from the cladding material, converting the differential signal into a binary value, and detecting edges of the cladding material substrate portion and the cladding portion. By measuring the width of the substrate part and/or cladding part,
Accurate width measurements can always be performed without being affected by variations in the brightness level of reflected light, only one binary level is required, and the output value of the width measuring device matches the actual value measured using a microscope. An object of the present invention is to provide a width measuring device for a partial cladding material that can prevent measurement errors due to poor optical conditions by optically adjusting the angle of an image sensor camera with respect to the cladding material in advance. .

The width measuring device for a partially clad material according to the present invention includes:
A partial cladding material in which another metal strip is superimposed in the longitudinal direction of the substrate as a cladding part on a part of the widthwise part of the metal strip serving as the substrate part is imaged by at least one-dimensional image sensor, and the substrate part is formed based on the imaged signal. as well as/
Or, in a device for measuring the width of the cladding part, there is a differentiation circuit that differentiates the imaging signal, a binarization circuit that binarizes the differential signal at an appropriate level, and a circuit that measures the width of the substrate part and the cladding part based on the binarized signal. It is equipped with a width calculation unit that detects the edge position of the edge portion and calculates the width of the substrate portion and/or the cladding portion, and a microscope that detects the boundary between the substrate portion and the cladding portion and measures the width of the cladding portion. , the image sensor is characterized in that the optical angle can be adjusted with respect to the partial cladding material.

[Effect]

In the present invention, by analyzing the binary processed signal of the differential waveform of the imaging signal, even if there are variations in the brightness level, the binary signal becomes 0 in the substrate part and the cladding part, and the end face position of the cladding material is Since only the boundary position between the substrate portion and the cladding portion has a complex pulse waveform, accurate width measurement can be performed without being affected by changes in brightness level, and accurate angle adjustment can be performed using a microscope.

〔Example〕

The present invention will be explained below based on drawings showing embodiments thereof. FIG. 1 is a schematic diagram of the apparatus of the present invention, and 1 in the figure shows the rotation of the table rolls 2, 2, etc. due to the operation of a drive system (not shown) in the longitudinal direction (in the direction of the white arrow in the figure). This is the clad material being transported. The clad material 1, whose perspective view is also shown in FIG. 2, has a substrate made of a 42% Ni-Fe alloy.
It has a clad part 1a in which Al is laminated in the longitudinal direction on a part of its surface in the width direction.

Further, in the figure, 3 is a light source, and 4 is an image sensor camera that images the surface of the cladding material 1 using light projected from the light source 3. and image sensor camera 4
The differentiating circuit 5 receives the video signal of the captured image and performs differential processing on it, and the signal differentiated by the differentiating circuit 5 is converted into 2 at a certain appropriate level by the binarizing circuit 6.
Valued. Further, based on the processed signal of the binarization circuit 6, a width calculating section 7 calculates the substrate part width and the clad part width.

Further, a recorder 11 is connected to the width calculating section 7 through a D/A converter 10, so that changes in the widths of the substrate portion and the cladding portion can be continuously recorded. In addition, a judgment circuit 12 is connected to the width calculation unit 7 to judge whether the calculated value width is within an allowable range, and an alarm 13 is connected to the judgment circuit 12. When the width of the substrate portion or the cladding portion shows an abnormal value, An alarm signal is displayed.

On the other hand, similarly to the image sensor camera 4 for width measurement, an image sensor camera 14 for taking an image of the surface of the cladding material 1 is provided at an appropriate distance away from the cladding material 1, and the image sensor camera 14 includes the differential circuit 5, A differentiation circuit 15 and a binarization circuit 16 having the same functions as the binarization circuit 6 are connected. Further, in this embodiment, a defect detector 17 is connected to the binarization circuit 16 for detecting surface defects based on the processed signal of the binarization circuit 16. The image sensor cameras 4 and 14 are both two-dimensional image sensors, and their scanning direction is based on the cladding material 1.
It is designed to intersect with the conveyance direction.

Further, a microscope 8 connected to a micrometer 9 is installed at an appropriate distance away from the clad material 1 upstream in the transport direction of the clad material 1. While observing the clad material 1 with the microscope 8, the substrate is The width of the cladding part is measured with the micrometer 9 by aligning the boundary between the cladding part and the cladding part (see Figure 9), then changing the field of view and aligning the line in the microscope 8 with the other boundary. There is.

Next, a detailed procedure for measuring the width of a cladding material using the apparatus of the present invention will be explained. First, alignment of the image sensor camera 4 will be explained. The cladding material 1 is observed with a microscope 8, the boundary between the substrate part and the cladding part is sequentially aligned with the line inside the microscope 8 (see FIG. 9), and the width of the cladding part is measured with a micrometer 9. Then, the position of the measured portion of the clad material 1 is moved to the field of view of the image sensor camera 4, and the width calculation unit 7
In order to equalize the output values of Distance from the 1st edge of the cladding material to the end of the scan (distance of parts a and b in Fig. 3, which will be described later)
The image sensor camera 4 is positioned so that the values are equal. This adjustment is performed because the former adjustment eliminates sensitivity errors in the width direction of the image sensor camera 4, and the latter positioning prevents measurement errors due to lens aberrations.

On the other hand, regarding the image sensor camera 14, it is sufficient that the reflected light enters the image sensor camera 14, and there is no need for particular fine adjustment.

Next, a procedure for measuring the widths of the substrate portion and the cladding portion of the cladding material 1 will be explained. As described above, the image sensor camera 4 is positioned, and the clad material 1 is rotated as the table rolls 2, 2...
When the material is transported, light is emitted from the light source 3 in the width direction of the surface of the clad material 1, and the image sensor camera 4
The surface of the cladding material 1 is imaged. FIG. 3 is an example of an imaging signal waveform diagram of the image sensor camera 4, in which A, B, and C represent the substrate portion A, cladding portion A, and substrate portion U of the cladding material 1 shown in a perspective view in FIG. Also, a corresponds to the part from the scan start point to the 1st edge of the cladding material (in other words, the background), and b corresponds to the part from the 1st edge of the cladding material to the scan end point (in other words, the background). .

The image pickup signal as shown in FIG. 3 is input to the differentiating circuit 5, where it is subjected to differential processing. FIG. 4 is a differential signal waveform diagram obtained by differentiating the image pickup signal shown in FIG. , A, and the boundary positions of A and C), the amount of change is only the variation in the brightness level, so when differentiated, all values become close to 0 as shown in FIG. 4.

Next, in the binarization circuit 6, the differential signal as shown in FIG. 4 is binarized at the level shown by the broken line in FIG. 4 to obtain a binarized signal diagram as shown in FIG. In Fig. 5, a indicates the end face position of A, b indicates a rising signal indicating the boundary position between A and I, c indicates the boundary position between A and C, and d indicates a falling signal indicating the end face position of C. , and other parts are 0, so the edge positions of the proximal end and cladding can be detected accurately. Next, the width calculating section 7 calculates the widths of the respective parts of the clad part A, the substrate parts A and C based on the binary signal diagram as shown in FIG.

Then, the calculated value is D/A converted and digitally recorded in the recorder 11, and the determination circuit 12
is input and exceeds the permissible range, an alarm signal is displayed by the alarm device 13.

As described above, the procedure for measuring the width of the substrate and cladding parts is explained, but since the device of the present invention clearly displays the boundary position between the substrate part and the cladding part, it is possible to detect the positional deviation of the cladding part (Al layer) relative to the entire width of the cladding material. Of course, both can be detected at the same time.

Next, the details of the operation for detecting surface defects will be explained. Similar to the width measurement procedure described above, clad material 1
The surface is imaged by the image sensor camera 14.
FIG. 6 is a waveform diagram of the imaging signal, and in the figure A,
A and C are the same as in Figure 3. Next, the imaging signal as shown in FIG. 6 is input to the differentiating circuit 15, where it is subjected to differential processing. 7 is a differential signal waveform diagram obtained by differentiating the image pickup signal in FIG. 6 by the differentiating circuit 15, and FIG. FIG. 2 is a diagram of a binarized signal obtained by level binarization indicated by a broken line in FIG.
If the inspection surface of the cladding material 1 is normal, the rising signals a and b indicating the end face position of the substrate part A, the boundary position between the substrate part A and the cladding part A, and the boundary position between the cladding part A and the substrate part C, respectively. , four rising or falling signals, falling signals c and d, respectively indicating the position of the end surface of the substrate part C, should be seen, but in FIG. 8, a falling signal e other than the four mentioned above is detected. ing. Therefore, the defect detector 17 detects a surface defect existing on the substrate part A based on the falling signal e shown in FIG.

When a surface defect is detected by the defect detector 17, an alarm signal is displayed on the alarm 23.

In this embodiment, a case has been described in which a two-dimensional image sensor camera is used to capture an image, but it goes without saying that a one-dimensional image sensor camera can be used in the same manner.

〔effect〕

As described in detail above, in the apparatus of the present invention, the width is measured based on the differential signal of the imaging signal representing the brightness of the reflected light of the cladding material, so accurate width measurement is possible regardless of variations in the brightness level. Furthermore, since the image sensor angle and position are adjusted in advance in accordance with the model values, errors in the width direction of the cladding material of the image sensor can be eliminated. Further, in the above-mentioned embodiments, the present invention has excellent effects such as being able to measure the width of the substrate portion and the cladding portion and detect surface defects at the same time.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram of the device of the present invention, Fig. 2 is a perspective view of the cladding material, Figs. Differential signal waveform diagrams in Figures 3 and 6, Figures 5 and 8 are binary processing signal diagrams in Figures 4 and 7,
The figure is a schematic diagram of the field of view of the microscope, and Figures 10 and 12 are waveform diagrams of imaging signals of cladding materials related to conventional equipment.
FIG. 11 is also a binarization processing signal diagram. 1... Clad wood, 2... Table roll, 3
...Light source, 4,14...Image sensor camera,
8...Microscope, 9...Micrometer.

Claims (1)

[Scope of Claims] 1. A partial cladding material in which a part of a metal strip serving as a substrate portion in the width direction is overlapped with another metal strip in the longitudinal direction of the substrate as a cladding portion is imaged with at least one-dimensional image sensor. , a device for measuring the width of a substrate portion and/or a cladding portion based on an imaging signal, which comprises: a differentiation circuit that differentiates the imaging signal; a binarization circuit that binarizes the differentiated signal at an appropriate level;
A width calculating section detects the edge position of the substrate section and cladding section based on the value signal and calculates the width of the substrate section and/or the cladding section; and a width calculating section that detects the boundary between the substrate section and the cladding section and calculates the width of the cladding section. 1. An apparatus for measuring the width of a partial cladding material, comprising: a microscope for measuring the width of the partial cladding material; and a microscope for measuring the width of the partial cladding material.