JP3349598B2 - Metallized film defect detection method for capacitors - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a capacitor metal in which a metal-deposited surface (vapor-deposited portion) and a non-deposited surface (margin portion) formed continuously on a base film are alternately formed in stripes. The present invention relates to a method for detecting a defect of a functionalized film during its production.

[0002]

2. Description of the Related Art In general, a metallized film used for manufacturing a capacitor element is well known as a substrate for a wound capacitor or a multilayer capacitor. The metal-deposited film is manufactured by providing a continuous metal non-deposited portion (margin portion) along one side edge in the flow direction of the metal-deposited film in order to prevent an electrical short circuit. This margin portion, before applying a plurality of narrow tapes to the surface of the base film, or applying a masking by a method such as applying oil, and then depositing metal, and then the center of the margin portion By slitting and winding with a blade of a slitter device, it is manufactured as an individual deposited film for a capacitor element.

[0003] In the vapor-deposited film for a capacitor element manufactured in this way, it is necessary to strictly control the width of the metal vapor-deposited portion and the margin portion for quality control, and strictly control the vapor-deposited surface of the metal vapor-deposited portion. Need to be managed. This is because the capacity of the capacitor formed later as a product is determined by the capacity of the metal deposition part, and if there is a pinhole or linear defect in this metal deposition part, the product will not be constant and the product will vary. It is. For this reason, conventionally, a slitter apparatus for cutting a margin portion is mainly inspected visually. However, it is difficult to detect a defect in a metal-deposited film moving at a high speed, and therefore, a method for detecting a defect in a metallized film using a CCD camera has been used.

[0004]

By the way, the detection method using a CCD camera requires a large imaging space, and it is difficult to incorporate it into a mixed slitter device. In addition, the metallized film for a capacitor element has a metal-deposited surface and a transparent margin formed in stripes in the moving direction, and when the CCD element is scanned in the width direction of the metallized film, the transparent margin is formed. The strong light of the camera CC
D detects the charge, causing leakage of electric charge to a pixel adjacent to a CCD element called so-called smear, making it difficult to detect a defect.

[0005] The present invention has been made in view of such a point, pinhole-shaped and linear defects on the metal deposition surface of the metallized film for the capacitor during the manufacturing,
It is an object of the present invention to provide a detection method that can surely detect with a simple device.

[0006]

According to the present invention, a high-frequency fluorescent lamp is arranged on one side of a sheet surface of a metallized film, and a light-shielding plate having a slit in a width direction on the other side corresponding thereto is arranged and arranged in a flow direction. The metallized film is irradiated with diffused light from the high-frequency fluorescent lamp, and light transmitted from two measurement areas in the flow direction of the metallized film is transmitted to the metallized film by the two-divided light-receiving element. as received, the signal a from the two light receiving elements, a sum signal a + B and the difference signal a-B and calculates to output from B, these
The change amount of the sum signal and the difference signal is set in advance.
Compared to each set value, and a change that is greater than the set value was entered.
It detected to be defective when, thereby a metallized film defect detection method for a capacitor which is adapted to detect defects in the metal deposition portion of the metallized film capacitor.

[0007]

The two measurement areas a and b are set on the upstream side and the downstream side in the flow direction of the metallized film by the two-divided light receiving element and the light shielding plate having the slit. Signals A and B obtained through divided light receiving elements
By using the sum signal A + B and the difference signal AB of
Defects in the metallized portion of the metallized film in which the metallized portion and the non-metallized portion are formed in stripes in the moving direction can be reliably detected with a simple and compact device.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing a schematic configuration of a detection device that performs defect detection, and FIG. 2 is a side view. That is, the high-frequency fluorescent lamp 1
And a plurality of two-divided light receiving elements 3 are installed so as to face the opposite sides in parallel with the width direction of the metallized film 2. A light-shielding plate 4 provided with a slit 4a having a predetermined length and width is provided between each two-divided light receiving element 3 and the metallized film 2. A slit 4a provided in the light shielding plate 4
Thus, optical signals A and B incident on the two light receiving sections 3a and 3b of each two-divided light receiving element 3 are obtained.

On the metallized film 2 having a width of 640 mm or less, for example, a metal-deposited portion 2a having a width of 40 mm is formed in a 16-stripe shape with a non-deposited portion (margin portion) 2b (FIG. Is shown). In this embodiment, pinhole-shaped defects and linear defects mainly present on the metal deposition portion 2a of the metallized film 2 are detected.
The metallized film 2 moves at a high speed in the direction indicated by the arrow, and the moving speed is 50 m / min to 300 m / min.

Light transmitted through the two measurement areas a and b on the upstream side and the downstream side of the metallized film 2 passes through a slit 4 a on a light shielding plate 4 provided in the width direction of the metallized film 2,
A flow provided at a predetermined distance corresponding to the slit 4a
Light receiving portions 3a and 3b of the two-divided light receiving element 3 arranged in the directions
To reach. A region a reaching the light receiving portion 3a and a region b reaching the light receiving portion 3b from above the metallized film 2 are located at positions shifted to the upstream side and the downstream side in the flow direction of the metallized film 2. These are the measurement areas a and b.

[0011]

[0012]

The two light receiving elements 3a and 3b are therefore made of metal.
Strip of opaque metal vapor formed in striped film 2
The width direction of the attaching portion 2a and the margin portion 2b which is a transparent non-evaporated portion
The amount of light from the two measurement areas a and b transmitted through
When receiving the light and measuring the full width, the two-divided light receiving element 3
The measurement is performed by arranging 16 linearly in the width direction. This
Thereby, the distance of about 1 mm in the moving direction of the metallized film 2
Total light transmitted through the entire width of the measurement areas a and b before and after
The amount will be received. FIG. 3 shows an enlarged view of a part of the metallized film 2. Metal deposition part 2 of metallized film 2
For example, if a pinhole indicated by reference numeral 5 exists in a, it can be regarded as a change in the amount of light when passing through the measurement areas a and b at different positions on the upstream side and the downstream side in the flow direction of the metallized film 2. Therefore, by using the difference signal AB between the signals A and B of the two light receiving units 3a and 3b, it is possible to obtain the defect detection signal O as shown in FIG. Here, C is a noise signal, and O
Is the difference signal.

In the case of a large defect such as a linear defect, the sum signal A + of the signals A and B of the two light receiving sections 3a and 3b is used.
By using B, a sum signal P as shown in FIG. 5 is obtained. This is the total amount of light transmitted through the measurement areas a and b. The sum signal P is affected by the size of the margin portion 2b existing in the measurement areas a and b. The sum signal P is constant. Metallized film 2
If there is a large defect such as a scratch existing in the metal deposition portion 2a of
Since a defect signal (a change of A + B) due to a flaw or the like is further added to the sum signal from the position where the defect exists, it can be detected from the change amount of the sum signal P.

The difference signal O is obtained by detecting light from the measurement areas a and b, whose positions are slightly shifted, by the two light receiving sections 3a and 3b and subtracting the respective signals. Even so, the signal changes in both the light receiving sections 3a and 3b, so that the difference signal O does not change. Therefore, the S / N ratio is excellent, and a minute defect can be easily detected. In this example, a minute defect of 0.5 mm × 0.5 mm could be detected. On the other hand, the sum signal P is equal to the measurement area a,
b is a signal that gives the total transmitted light amount, and this signal captures a change in light amount. Therefore, when the signal includes the transparent margin portion 2b or there is strong disturbance light, it is affected by these. Therefore, the noise signal becomes large, and a small defect cannot be detected, but only a large defect is detected.

Next, the measuring method will be briefly described with reference to the block diagram of FIG. The light transmitted by the high-frequency fluorescent lamp 1 and having passed through the two measurement areas a and b at different positions in the moving direction of the metallized film 2 passes through the slit 4 a of the light shielding plate 4.
Is detected by the light receiving portions 3a and 3b of the two-divided light receiving element 3 Light receiving portion 3a of the light receiving device 3, the signal from 3b is Ru is converted by a current-voltage converter 7. AB, which is one signal path, amplifies the difference signal by the differential AC amplifier 8 via the capacitor, and inputs only the AC component to the comparator 10 via the capacitor. The other signal path, A + B, is D
After being DC-amplified by the C amplifier 9, the changed component enters the comparator 11 via the capacitor.

The comparators 10 and 11 are connected to current-voltage converters 12 and 13 for setting the sensitivity, respectively. The values set by these converters and the light-receiving portions 3a and 3b of the two-division light-receiving element 3 are used. Are compared, and only when a detected value equal to or greater than a set value is input, a small defect output Q such as a pinhole and a large defect output R such as a linear scratch are output. It is configured to:

[0018]

As described above, according to the metallized film defect detecting method for a capacitor of the present invention, expensive C
By calculating the difference signal and the sum signal of a simple two-segment light receiving element without using a CD, it is possible to reliably detect defects in the metal deposition portion of a striped metallized film that moves at high speed. Becomes The light source and the detector are both formed of elongated members, and can be mounted close to each other, and can be easily installed between the rollers of the slitter without taking up space. Therefore, quality control is significantly improved, and a highly accurate product can be manufactured.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a schematic configuration of a detection device for explaining a method for detecting a metallized film defect for a capacitor according to the present invention;

2 is a side view of FIG. 1,

FIG. 3 is an enlarged perspective view of a part of the metallized film;

FIG. 4 is a waveform diagram of a difference signal;

FIG. 5 is a waveform diagram of a sum signal,

FIG. 6 is a block diagram of a measuring device.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 high-frequency fluorescent lamp 2 metallized film 3 two- piece light receiving element 4 light-shielding plate 4 a slit 5 point-like defect 7 current-voltage converter 8 differential AC amplifier 9 DC amplifier 10, 11 comparator 12, 13 current-voltage converter 14 capacitor a , B measurement area

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-54-158987 (JP, A) JP-A-4-1668638 (JP, A) JP-A-1-1977639 (JP, A) 7105 (JP, Y1) (58) Field surveyed (Int. Cl. ⁷ , DB name) G01N 21/892 G01N 21/894 H01G 4/18

Claims (1)

(57) [Claims] 1. A high-frequency fluorescent lamp is arranged on one side of a sheet surface of a metallized film, a light-shielding plate having a slit in a width direction is arranged on the other side corresponding to the high-frequency fluorescent lamp, and a two-divided light receiving element arranged in a flow direction is arranged. Irradiating the diffused light from the high-frequency fluorescent lamp to the metallized film so that the light transmitted from the two measurement areas in the flow direction of the metallized film is received by the two-divided light receiving element, A sum signal A + B and a difference signal AB from the signals A and B from the light receiving element are calculated and output, and a change in the sum signal and the difference signal is calculated.
Compare with each set value set in advance, and
If the above change is input, it is detected as a defect, and as a result, the metallized part of the metallized film for capacitors is detected .
A method for detecting a defect of a metallized film for a capacitor, wherein the defect is detected.