JPH0612749B2 - Method and apparatus for manufacturing multilayer capacitor - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and a method for manufacturing a multilayer capacitor having a film-shaped metal layer on one surface thereof and a plurality of sheet-shaped dielectric layers independent of each other. Regarding the device.

[0002]

2. Description of the Related Art An example of such a conventional capacitor is disclosed, for example, in U.S. Pat. No. 3,670,378, together with its manufacturing method and manufacturing apparatus. According to this method, first, a dielectric layer having a width shorter than the thickness of the drum and a film-like metal layer are alternately laminated on a drum having an appropriate thickness and wound for a predetermined number of layers. When the winding for the predetermined number of layers is completed, the separation layer is wound once for one rotation of the drum (that is, for one layer), and the dielectric layer and the film-shaped metal layer are overlapped on the separation layer again. The layers are alternately wound for a predetermined number of layers. If necessary, another separating layer is formed thereon, and the same winding process is repeated.

However, in this conventional method, every time one layer of the dielectric layer and the film-shaped metal layer are wound around the drum, they are alternately left and right along the widthwise direction (axial direction or thickness direction of the drum). Since the winding position on the drum is shifted by a predetermined dimension, the film-shaped metal layers are in a relationship of being shifted left and right for each layer after the winding is completed. That is, for convenience of understanding, for example, the film-like metal layer closest to the drum is referred to as a first layer, and the second-layer metal layer laminated with a dielectric layer sandwiched on the first-layer metal layer. Are referred to as the second layer, and when the layers are numbered in order, the first, third, fifth,
..... and the odd-numbered metal layer groups and the second, fourth, sixth, ...
... The even-numbered metal layer groups have the same end positions in the width direction in each group, but the both-end positions of each metal layer in the odd-numbered group and the even-numbered group in the even-numbered group The positions of both ends of each metal layer are offset from each other in the width direction.

In this conventional method, metal is sprayed on both end surfaces in the width direction of the alternating laminated structure of the dielectric layers and the metal layers. Then, as described above, since the odd-numbered metal layer group and the even-numbered metal layer group are displaced from each other in the width direction, for example, on the left end face in the width direction of the laminated structure, only the odd-numbered metal layer group is formed. Are electrically connected to each other by the metal material sprayed on this left end surface, while on the right end surface of the laminated structure, only even-numbered metal layers are electrically connected to each other by the metal material sprayed on this right end surface. Connected to. Of course, since the dielectric layers are interposed in the stacking direction between the odd-numbered metal layer groups and the even-numbered metal layer groups, they are electrically insulated from each other.

In this way, according to the conventional method, as in the case of putting a knife in a round cake or a ring donut with a knife in a radial direction to separate them, a plurality of the alternately laminated structures wound around a drum are circumferentially arranged. When cutting is performed in the radial direction at each point, and as described above, the separation layers are sandwiched and wound and formed, by removing the separation layers after cutting, the sheet-shaped dielectric layers are respectively removed. And individual laminated capacitors each having a predetermined number of laminated film-like metal layers are cut out. Obviously, in the individual multilayer capacitors made in this way,
The above-mentioned spraying method (spray method) on one end face in the width direction
The metal material formed in 1 constitutes one electrode surface of the capacitor, and the metal material formed in the other end surface forms the other capacitor electrode surface. Inside the multilayer capacitor, each of the plurality of metal layers electrically connected to one electrode surface is electrically connected to the other electrode surface through the dielectric layer in the stacking direction. Since the metal layers are inserted into a pair or adjacent to each other so as to be nested or misaligned, the capacitance can be expected between the surfaces of the electrodes, and the multilayer capacitor functions as expected.

[0006]

However, in the above conventional method or apparatus, each dielectric layer on the drum,
When the metal layers are wound without being able to maintain the above-described predetermined deviation width for each layer due to undulations or the like, if the upper and lower dielectric layers adjacent to each other in the stacking direction or the metal layers adjacent to each other are stacked. In some cases, the predetermined positional relationship in the width direction cannot be maintained. Nevertheless, in this conventional method, there is no means for suppressing the deviation of each dielectric layer and each metal layer from the predetermined path when winding around a drum, and in practice, such an unexpected deviation easily occurs. of course,
Such a positional shift causes a short circuit accident between a pair of electrodes of the multilayer capacitor, or a deviation from a permissible range for a predetermined capacitance value even if it does not reach that point. For example, as described above, the odd-numbered metal layer group and the even-numbered metal layer group have to be deviated from each other by a predetermined distance in the width direction, but the deviated width is not sufficient in the above-described manufacturing process. When metal spraying is applied to the left and right end surfaces of the alternately laminated structure of the dielectric layers and the metal layers, the electrical properties of one sprayed metal material should be electrical only on one edge side in the width direction. It is possible that all or some of the metal layers that should be in contact with the metal contact the metal material sprayed on the other end face on the other end edge side in the width direction. Of course, in this case, the multilayer capacitor is a defective product in which both electrode surfaces are short-circuited. Even if it is not so, it is difficult to maintain the geometrical positional relationship, which means that the capacitance value of the produced multilayer capacitor is likely to change. This is because the capacitance value is greatly affected by the area in which the metal layer connected to one electrode surface and the metal layer connected to the other electrode surface face each other with the dielectric layer sandwiched therebetween. In addition, even if the metal layers belonging to the same group are not separated by a predetermined distance in the stacking direction, the capacitance value is likely to vary from capacitor to capacitor. The metal layer group that should be commonly connected to the electrode surface of one end face (for convenience, the first group) and the metal layer group that should be commonly connected to the electrode surface of the other end face (hence this is the second group) (Referred to as) is displaced from each other by a predetermined distance in the width direction,
Even between a pair of metal layers that belong to each group and are adjacent to each other in the stacking direction, since the metal layers belonging to the other group do not intervene up to the site near the end face electrode surface, A considerably large space is created in the stacking direction between the pair of adjacent metal layers. Therefore, when this space portion is crushed by some factor during the manufacturing process and the pair of adjacent metal layers are extremely close to each other, the capacitance is increased. There were also unexpected fluctuations in the values.

The present invention has been made to solve the above-mentioned conventional drawbacks, and the most basic purpose thereof is that even if the outer shape is a general type, the internal structure is different from the conventional one,
Further, the difference is to provide a manufacturing method or a manufacturing apparatus of a multilayer capacitor, which can affect the manufacturing cost and performance better than the conventional example. However, in the following, for simplicity, the multilayer capacitor according to the present invention may be simply referred to as a capacitor.
To further subdivide the object of the present invention, one is:
Even if the positional relationship in the width direction between the metal layers facing each other across the dielectric layer in the stacking direction slightly deviates from the predetermined relationship, both ends in the width direction of the alternate stacked structure of the dielectric layers and the metal layers The metal material sprayed on the surface makes electrical contact only with the corresponding first and second metal layer groups, respectively, as expected.
It is sometimes disclosed to provide a manufacturing method or apparatus suitable for providing a capacitor having an internal structure that does not contact the metal layer of the other group. Secondly, in this type of capacitor, the area portion where the metal layer belonging to the first group and the metal layer belonging to the second group face each other in the stacking direction with the dielectric layer sandwiched between them It becomes an effective capacitance forming portion, but on both sides in the width direction of this capacitance forming portion, that is, in the length portion where the metal layers belonging to each group extend to connect to the corresponding end face electrode surfaces, There is also a case of providing a manufacturing method or a manufacturing apparatus of a capacitor having an internal structure that does not cause a large fluctuation in the capacitance value of the capacitor even if the crush deformation occurs in the stacking direction as in the conventional case. Further, the present invention provides a method for manufacturing a multilayer capacitor of this type, which is much faster than a conventional manufacturing method and can reliably manufacture a multilayer capacitor having the above structure. Also as a manufacturing apparatus, the present invention provides an apparatus capable of reliably maintaining a predetermined widthwise displacement relationship between a metal layer belonging to the first group and a metal layer belonging to the second group within predetermined dimensions and an allowable range. It will be provided.

[0008]

In order to achieve the above-mentioned object, the present invention comprises a plurality of sheet-like dielectric layers each having a metal layer formed on one surface and independent of each other. As a method of manufacturing a laminated capacitor, which has a laminated structure, and in which a plurality of metal layers independent of each other in the laminated structure are electrically connected to one end of a pair of capacitor terminal electrodes, a. A plurality of dielectric layers having a width and continuous in the length direction orthogonal to the width are formed on the surface of the dielectric layer and are continuous in the length direction at predetermined intervals in the width direction, each of which has a predetermined width. The metal layer is formed in a strip shape, and between adjacent ones of the plurality of strip-shaped metal layers, metal-free zones having no metal are formed over a predetermined width, respectively. The first and second webs with respect to the first web The plurality of metal-free zones formed on one web are continuously cut in the lengthwise direction at a position slightly separated from one side in the width direction, and the second web is treated with the second web. The first and second webs are respectively cut by continuously cutting in the length direction at a position slightly distant from the plurality of metal-free zones formed on the web to the other side in the width direction. Dividing into a plurality of strips; b. Winding the first web composed of the divided plurality of strips on the same drum; c. Forming a plurality of strips also divided into the plurality of strips A second web together with the plurality of strips of the first web, with the widthwise one edge of each strip of the first web extending beyond the same widthwise one edge of the second web. Tensioned to the specified width outward Winding the first and second webs on the drum while offsetting each other in the width direction; d. Winding the strips of the first and second webs together on the drum. As a result, a plurality of adjacent strips are formed around the drum in the widthwise direction, and the strips of the first and second webs are alternately laminated in a plurality of layers in the radial direction of the drum. Removing each of the plurality of rings including the alternate laminated structure from the drum; and e. A metal material that constitutes each of the terminal electrodes with respect to both end faces in the width direction of the alternate laminated structure of each of the rings. A step of cutting the alternating laminated structure having the terminal electrodes attached thereto at a plurality of positions parallel to the width direction; and a laminated type having at least six steps a. To f. In total. We propose a capacitor manufacturing method.

Further, as a manufacturing apparatus suitable for use in this manufacturing method, a first and a second having a metal layer on one surface of a dielectric layer having a width of g. A first and a second supply roller on which the web is pre-wound; h. Selectively one or both of the first and second webs drawn from the first and second supply rollers A rotary drum that winds up together in a combined state; i. The first and second webs at positions where the first and second webs drawn from the first and second supply rollers are in contact with the rotary drum, respectively. The first and second pressing members press the respective webs against the surface of the rotary drum so that the webs are wound around the rotary drum while maintaining a state where they are displaced from each other by a predetermined dimension in the width direction. A pressure roller; j. Said first, second First and second idler rollers located between the second pressure roller and the first and second supply rollers for applying tension to the first and second webs respectively; k. On the one pressure roller or immediately before the first pressure roller, the metal layer on the dielectric layer of the first web is divided into a plurality of strip-shaped metal layers arranged in the width direction. For each of the plurality of metal-free zones on the dielectric layer, the first web is continuously cut in the length direction at a position slightly apart from one side in the width direction to form a plurality of strips. A first cutting station that divides into: a. A width of the metal layer on the dielectric layer of the second web on or immediately prior to the second pressure roller. In each of the plurality of metal-free zones on the dielectric layer which are divided into a plurality of strip-shaped metal layers arranged in parallel in the direction And a second cutting station for continuously cutting the second web in the lengthwise direction at a position slightly apart from the other side in the width direction and dividing the second web into a plurality of strips; m. As a result of winding the strips of the first and second webs together, a plurality of strips are formed adjacent to each other in the width direction around the drum, and each of the first web is formed in the radial direction of the drum. After removing from the drum a plurality of rings having an alternating laminated structure in which strips and strips of the second web are alternately laminated in a plurality of layers, both ends of each of the rings in the width direction of the alternating laminated structure. A device for adhering a metal material constituting each of the terminal electrodes to a surface; n. A device for cutting the alternating laminated structure with the terminal electrodes at a plurality of positions parallel to the width direction; Eight components required An apparatus for manufacturing a multilayer capacitor having at least items g. To n. Is proposed.

As described above, the metal-free zones extending on the dielectric layers of the respective webs in the lengthwise direction and in a parallel relationship with each other are formed in advance by the manufacturer of this type of web. It is also possible that such webs are already provided with such metal-free zones while being wound around the first and second feed rollers, as far as the manufacturing apparatus of the present invention is concerned. Alternatively, the web manufacturer may receive the provision of a metal layer formed on the dielectric layer in a series or on the entire surface. In the latter case, before each web passes through each cutting station described above with respect to the manufacturing apparatus of the present invention, the metal is applied to the metal layer formed in series on the dielectric layer of each web. Each required metal-free zone may be formed by a laser device or the like that continuously removes the material in the width direction at predetermined intervals over the predetermined width in the length direction.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows, as an embodiment of the present invention, a manufacturing apparatus suitable for manufacturing a multilayer capacitor. First, it has a pair of supply rollers 2 and 4. Webs A and B are wound around the supply rollers 2 and 4, respectively. The webs A and B are shown only for one of the webs B in the figure, but as shown in the cross section in FIG. They may be the same member composed of the metal layer 8 and the superposed layer. Hereinafter, when simply referred to as a web, it means a polymerized layer in which the metal layer 8 is previously formed on the dielectric layer 6. Dielectric layer 6 of each web A, B
As a specific material for the above, a suitable plastic such as resin marketed under the trademark "Mylar" can be selected. On the other hand, the film-shaped metal layer 8 may be an aluminum layer or the like deposited on the dielectric layer 6 by vapor deposition, and both the dielectric layer 6 and the metal layer 8 are extremely thin. For reference purposes only, and not for limitation, a prototype of the present applicant uses a web in which a metal layer 8 of about 500 angstrom is deposited on a dielectric layer 6 having a thickness of 0.001 inch or less. I was there. In the following description, components belonging to the respective webs A and B, but having the same or similar functions to each other, have the same numeral reference followed by the lowercase alphabets a and b. In some cases, it may be discriminated which web the component belongs to. For example, when the dielectric layer 6a is used, it indicates that it is the dielectric layer of the web A. On the contrary, such a component without a lowercase alphabetic subscript can be commonly used by both webs A and B. Further, even if the reference numerals in the drawings have alphabetical subscripts a and b, when such subscripts are omitted in the description, for example, although the reference numeral 8b is shown in the drawings, it is in accordance with the drawing. In the description below, only the metal layer 8 is mentioned, and when mentioned, the description there is related to such a metal layer.
This means that the contents can be similarly applied not only to the web B but also to the metal layer 8a of the web A.

However, as shown in FIGS. 3 and 4, the metal layer 8 formed on each of the dielectric layers 6 of the webs A and B (only the web B is illustrated in the drawing) is It is not formed so as to cover the entire surface of the dielectric layer 6, but is composed of a plurality of strip-shaped metal layers juxtaposed in the width direction of the web. In other words, between the adjacent strip-shaped metal layers, there is a region 10 continuously extending in the length direction of the web and having no metal layer over a predetermined width, in which the dielectric layer is provided. The surface of 6 is exposed. Therefore, this region is abbreviated as “metal-free zone” 10 hereinafter. Such metal-free zones 10 may have already been formed on the webs A and B when they are provided by the manufacturers of the webs A and B, or, as will be described later, on the entire surface of the dielectric layer 6. The webs A and B on which the metal layer is formed may be formed later by a laser burning method. Figure 1 again
Returning to, the webs A and B having the above-described structures are respectively wound around a series of roller groups described below, and then wound around a large-diameter rotating drum (or winding wheel) 20. The webs A and B drawn from the web supply rollers 2 and 4 first pass through the outer peripheral surfaces of the idler rollers 12a and 12b, but the rotation axes of these idler rollers 12a and 12b are the waviness of the drawn webs A and B. It is possible to move in the axial direction so that can be corrected. That is,
The idler rollers 12a and 12b can be axially moved together with the supply rollers 2 and 4 as a unit by adjustment using an existing edge guide sensor (not shown), and the webs A and B to be pulled out are always Without waviness
Try to move in a given direction as straight as possible. The webs A and B that have passed through the idler rollers 12a and 12b are then tension-sensitive idlers 14a and 14b.
Pass the outer peripheral surface of. This tension sensing idler 14a, 14b
Respectively detects the tensions of the webs A and B extending between the drum 20 and the supply rollers 2 and 4, and an existing variable drag clutch (not shown) attached to the supply rollers 2 and 4 is used. Send a tension signal. Although not shown in the figure, similarly, according to the existing technology, there is an adjusting device by a closed loop control system, which acts on the variable drag clutch to maintain the tensions of the webs A and B at desired preset values. work. The webs A and B that have passed the tension sensing idlers 14a and 14b are pressed by the pressure rollers 16a and 16b against the outer peripheral surface of the drum 20 while passing around the pressure rollers 16a and 16b. It is taken up in the state that it was made. In addition, each pressure roller 16
a and 16b, the rollers 15 and 17 are provided at the positions facing each other in the diametrical direction of the drum 20 in FIG.
Is a drum 2 for winding webs or strips.
It is a roller for maintaining a tightly wound state by stably pressing it to the 0 side.

Therefore, as is apparent, according to such a device, each web A, B passes through the space from the supply rollers 2, 4 on which they are first wound to the drum 20 on which the web is wound. It is maintained in a taut state with a predetermined tension in the path without hanging up. Therefore, as in the conventional example, an edge that simply guides both edges of the moving web.
Compared with the case where only the guide is provided, the predetermined widthwise displacement relationship (described later) between the web A and the web B does not deviate significantly from the permissible range and can be guaranteed very well. it can. Further, as will be described next, when cutting each web into the width required for each capacitor, unlike the above-described conventional example, in the case of the present invention, the cutting after being wound on the drum 20 is performed. But before each web A, B is wound onto the drum 20,
By passing through the respective cutting stations while maintaining a predetermined tension as described above, it is pre-cut into a plurality of strips having a width required for individual capacitors in the future.

Such cutting stations are shown in FIGS. 2 and 4 for web B and for web A in FIG. 7, but in practice, as will be described below, the position of the cutting blades. However, structurally, the components required for the cutting station of either web may be the same. To explain, each cutting station
In the illustrated case, it is provided between the pressure roller 16 and the tension sensing idler 14, and preferably at a position close to the pressure roller 16, and as shown in FIGS. 2, 4 and 7, respectively. A plurality of cutters 21 separated from each other in the width direction of the web at predetermined intervals, ...
And have. Each cutter 21, ... May be a razor blade or the like, as shown. The upper surface of the support bar 22 is sufficiently polished, and the upper surface of the support bar 22 stably supports the webs A and B passing therethrough. As shown in the enlarged view of the essential part of the cutter,
Slits are also provided to receive the cutting edges for cutting the webs A and B. However, the pressure roller 16 is provided with such a slit group, and the cutter 21 cuts the webs A and B into a plurality of strips arranged side by side in the width direction at the pressure roller 16. It may be. In any case, apply the appropriate tension as above,
In addition, if each of the webs A and B is cut by the cutter 21 in an environment in which the state can be maintained, it is usually difficult to cut the web material without wrinkling. Can be cut. As shown in FIG. 1, the pressure rollers 16a and 16b dedicated to the webs A and B are preferably separated by 90 ° or 180 ° around the axis of the drum 20.

However, regarding the division of the webs A and B into a plurality of strips arranged in the width direction, the following explanation can be made. FIG. 3 shows the division of the web B, and the plurality of cutters 21b
The web B is divided into a plurality of elongated strips 18b. Each of the plurality of dividing lines for the web B, that is, the position of each cutter 21b is provided on the surface of the dielectric layer at predetermined intervals in the width direction as described above. It is a position close to each of the metal-free zones 10, and in particular, a position a little distance apart from one side in the width direction of each of the metal-free zones 10 (left side in the case of illustration). Each strip 18b cut in this way
Respectively correspond to each one of the polymer layers (layers having a polymerizing relationship between the dielectric layer and the metal layer) in the internal laminated structure of the individual capacitors, which is particularly well shown in FIG. As described above, on the surface of the dielectric layer 6b for each of the cut strips 18b, one end edge is aligned with one end edge in the width direction of the dielectric layer 6b, but the other end edge is dielectric. A metal layer 8b that does not reach the other end of the body layer 6b and a metal layer 8b that faces the metal layer 8b in the width direction with the metal-free zone 10 interposed therebetween. The thin strip-shaped metal layer 24 that continuously extends is left. For convenience of explanation, the metal layer 24 having a narrow width and extending in a strip shape is hereinafter referred to as an “edge metal zone” 24.

On the other hand, although the structural parts used are the same, as indicated by an arrow 21dd in FIG.
A cutting station, in which the position of each cutter is on the other side in the width direction of each metal-free zone 10, that is, on the right side in this case, and at a position slightly separated, divides the web A into a plurality of strips 18a. Used for. Therefore, the arrangement relationship of the metal layer 8a, the metal-free zone 10, and the edge metal zone 24 on the dielectric layer 6a with respect to each strip 18a obtained by dividing the web A is as shown in FIG. The arrangement relationship of those relating to B is reversed left and right in the width direction. Further, as shown in FIG. 6, the strip 18a divided from the web A and the strip 18b divided from the web B are displaced from each other in the width direction (left and right) by a certain size. And
This misalignment relationship is already formed when wound around the drum 20 in FIG.

This can also be explained in more detail with reference to the schematic drawing of FIG. 5, which is a sectional view along the line 5-5 in FIG. However, in FIG. 5, each web or each strip 18 obtained by cutting each web is shown only by the outline along the cross section, and the metal-free zone 10 is shown by the portion where the outline is interrupted. The width of the strip 18 is shown in a much shortened state relative to its thickness. As already mentioned, each web A, B is previously divided into a plurality of strips 18 by the cutting station and then wound on the drum 20. First, in this embodiment, the first five windings on the drum 20 are ,
Only web A (cut into strips) is rolled up at once. This is shown in FIG. 5 by a portion where five symbols “A” are arranged from the portion in contact with the surface of the drum 20 toward the upper side in the drawing. When the web A of five layers is wound in the cross section along the radial direction in this way, the tip of the web B (also cut into a plurality of strips in the width direction) is placed on the uppermost layer via the pressure roller 16b. When they are placed, and the drum 20 is rotated again in this state to wind them around the drum together, the webs A for the first five layers described above are displayed in the order of " BA
Now, as shown by "BABABA", Web B
And a web A are alternately laminated. However,
Since the web B is wound around the web A while being displaced by a predetermined distance in the width direction (that is, the drum thickness direction or axial direction) of the web A, as shown schematically in FIG. Web B and Web A are drum 20
When they are wound on top of each other, they are offset from each other by a predetermined dimension in their width direction. In this way, when the alternately laminated structure portion of the webs B and A is formed, the supply of the web B is stopped again, only the web A is wound around the drum 20 for four revolutions, and five layers are continuously continued. Form a layer of web A. The reason why four rotations are sufficient is that when the alternating laminated structure of the web B and the web A is formed as described above, the layer located at the top is the layer of the web A. A laminated structure of only five continuous webs A is formed. The web A layers of five layers each on the radially inner side and the outer side, which are formed according to such a procedure, finally become reinforcing layers in the individual capacitors, and the alternately laminated structure portion of the intermediate web B and web A is effective. It becomes an active part or an effective capacitor area that generates the electric capacity of each capacitor.

However, as described above, each web A,
Since B is divided into a plurality of strips 18a, 18b in the width direction by passing through the respective cutting stations before being wound on the drum 20, the ring 3 with respect to the plurality of strips 18a, 18b.
A plurality of 0, ... Are fitted into the drum 20 along the thickness direction or axial direction of the drum, as schematically shown in cross section in FIG. Then, as described above, all the rings 30 are strips 18 a cut from the web A on the five reinforcing layers of the strip 18 a and strips 18 cut from the web B and the web A respectively.
strips 18a each having an active portion or an effective capacitor region having an alternating laminated structure of four sets of a and 18b and further cut as a reinforcing layer from the web A of five layers.
The structure has a layer group of. Note that in FIG. 5, for convenience of understanding, one ring 30 in the circumferential direction, which is shown beside the laminated structure denoted by reference characters A and B, is hatched with respect to one cross-section portion, and this constitutes a unit capacitor. It is clearly stated that it will be a laminated structure for. When the winding is completed in this way, each ring 30 is removed from the drum 20, and the metal material 40 is attached to both end faces in the width direction of each removed ring 30 by the same metal spray method as in the conventional method. Let This metal material 40,
40 is shown in FIG. 6, except that in this FIG.
As described above with reference to FIG. 5, the upper and lower five layers of reinforcing layers obtained by cutting from the web A are omitted, and only the effective capacitor region that should function as the capacitor, that is, the web A , B each of which is obtained by cutting the strips 18a and 18b from each other is shown by extracting only four alternately laminated structure portions. After the metal coatings 40, 40 on both end surfaces are formed, the ring 30 is radially cut at one location in the circumferential direction and elongated, and the elongated laminated structure is cut at a plurality of locations along the length direction. Then, a plurality of substantially rectangular capacitor structures are individually obtained. In this way, the strip portion for each capacitor obtained by cutting the alternately laminated structure of the strips 18 in parallel in the width direction at a plurality of locations in the lengthwise direction is as shown in FIG. In addition, the sheet-shaped dielectric layer 6 and the metal layer 8, the metal-free zone 10, and the edge metal zone 24 respectively formed on the sheet-shaped dielectric layer 6.

For convenience, the alternate laminated structure thus obtained as the internal structure of the individual capacitors, whichever may be either, is obtained from the strip 18a belonging to Web A, or from it. The sheet-shaped dielectric layers 6a belong to the first group,
Those belonging to Web B, on the other hand, are referred to as belonging to the second group. As shown in FIG. 6, in the capacitor of the present invention produced by the above-described manufacturing procedure, in the effective capacitor area portion, each sheet 18a belonging to the first group and each sheet 18b belonging to the second group are arranged in the width direction. However, a closer look reveals the following geometrical relationship between them. Each sheet 18a belonging to the first group
6, the film-shaped metal layer 8a formed on the sheet-shaped dielectric layer 6a corresponds to the left end of the dielectric layer 6a at the left end in FIG. 6, but the right end is The dielectric layer 6a does not reach the right end, and the metal-free zone 10 is sandwiched between the right edge of the dielectric layer 6a and the right edge of the metal layer 8a. Are formed. On the other hand, regarding each sheet-shaped dielectric layer 6b belonging to the second group, as described above with reference to FIG. 3, although the original configuration is the same, the cutting position of the web B is the same as that of the web A. Is different, the film-shaped metal layer 8b formed on the dielectric layer 6b
6 corresponds to the right end of the dielectric layer 6b at the right end in FIG. 6, but the left end does not reach the left end of the dielectric layer 6b, and a metal is not formed on the left end edge of the dielectric layer 6b. Layer 8
An edge metal zone 24 is formed so as to sandwich the metal-free zone 10 with the left end of b. Further, as also described above, with respect to the winding on the drum 20, as a result of shifting the webs A and B or the strip groups 18a and 18b from each other by a predetermined dimension in the width direction, each of the dielectric bodies belonging to the first group. The left end of the layer 6a is the dielectric layers 6b belonging to the second group.
Has a geometrical relationship in which it extends beyond the left end 36 to the left in the width direction, and conversely, on the right end side, the right end of each dielectric layer 6b belonging to the second group corresponds to that of each dielectric layer 6a belonging to the first group. Right edge 3
There is a relationship that exceeds 7 and further projects to the right in the width direction. Therefore, as described above, when the metal material 40 serving as the terminal electrode of the capacitor is sprayed on the both end surfaces by the metal spray method as described above, the metal material 40 sprayed on the left side is as shown in the correct state in FIG. The metal layer 8 on each dielectric layer 6a of the first group protruding to the left.
Only a can be electrically contacted, and the metal material 40 sprayed on the right side electrically contacts only the metal layer 8b on each dielectric layer 6b of the second group protruding to the right. be able to. As a result, a unit electric capacity can be obtained in the area portion of the pair of metal layers 8a and 8b sandwiching the dielectric layer 6 when viewed in the stacking direction and facing each other in the stacking direction. In the relationship that the electric capacities of are parallel according to the number of laminated layers, a pair of end face metal materials 40, 40,
That is, a desired capacitance value can be obtained between the pair of terminal electrodes 40, 40 of the capacitor.

However, such a capacitor internal structure according to the present invention cannot be sprayed properly as described above, or since each capacitor structure is quite small as described above, the metal material 40 sprayed on each end face is used. , 40 cannot be brought into contact with only the corresponding one group of metal layers 8 and the metal material inevitably reaches the end of the other dielectric layer,
A short circuit accident as a capacitor can be effectively prevented. This is because, even if the metal material that has penetrated inward in the width direction reaches not only the metal layer 8 of the target group but also the end portion of the dielectric layer 6 of the other group, the other metal layer 8 exists there. This is because there is only the edge metal zone 24 formed on the dielectric layer 6 of FIG. As is clear
This edge metal zone 24 is, so to speak, a “floating electrode”,
Due to the existence of the metal-free zone 10, the floating electrode 24 is not electrically connected to the metal layer 8 even though it is formed on the same dielectric layer 6. In other words, the metal-free zone 10 formed between the edge metal zone 24 and the metal layer 8 becomes a region for ensuring insulation between them, and thus the metal layers belonging to the first and second groups. 8
This is a region for ensuring insulation between a and 8b. Because of the existence of the edge metal zone 24, the metal material 40 by spraying never enters the metal-free zone 10. In addition, the metal-free zone 10 does not unexpectedly largely collapse. The gap in the stacking direction of the metal-free zone 10, that is, as is apparent in FIG. 6, the gap in the vertical direction between the pair of adjacent dielectric layers 6a and 6b in the region 10 is the edge metal on one side. This is because the band 24 is provided and the metal layer 8 is provided on the other side, so that it is maintained at a predetermined size. Therefore, the distance between the stacked metal layers 8a and 8b in the stacking direction can be kept substantially constant, particularly in the area of the facing area thereof, which greatly eliminates the variation of capacitance that can occur from product to product. Be useful.

FIG. 7 also shows an example of a main part that can be modified in the manufacturing method or apparatus of the present invention. The drawing is shown on the side of the web A, in front of a cutting station having a cutter 21a and a support rod 22a, an applicator 50 for applying a thin layer of adhesive on the surface of the web A, in particular on the metal layer 8a. Is provided. Although not limited, the adhesive used here may include an epoxy resin. However, even if it is on the metal layer 8a, when the above-mentioned alternate laminated structure of FIG. 6 is completed in the future, the metal spray 40 is overhanged from the opposite strip 18b or the opposite dielectric layer 6b in the width direction. Do not apply to the receiving area. The purpose of applying the adhesive is to allow handling without stripping the thin metal layer after being wound onto the drum. The thickness of the adhesive layer is preferably about 1 micron (1 μm) or less, and it is preferable that the adhesive layer is distributed not at the entire surface of the metal layer 8a but at a plurality of points. If you put it in this way, even if you use an adhesive,
Almost no loss in the efficient volume-to-capacitance ratio. These points also apply to the attachment of the adhesive to the metal layer 8b.

By the way, the metal-free zone 1 used in the present invention
The webs A and B with zeros can be purchased from the manufacturer of this type of web, already mentioned above, with such metal-free zones 10 already formed. However, the pre-made metal-free zone 10 may be too wide for a normal low-voltage capacitor. Therefore, in such a case, on the side of the capacitor manufacturer who uses the present invention, the webs A and B are pulled out from the supply rollers 2 and 4 and wound on the drum 20, in the middle of the route. As shown in FIG.
By passing through the laser burning station 52,
A plurality of parallel laser beams 53 spaced at predetermined intervals in the width direction are formed on the dielectric layers 6 of the webs A and B to form a predetermined interval, a predetermined width, and a predetermined number of metal-free zones 10. You can also do it. Practically, by such a method, the metal layer 8 formed on the entire surface of the dielectric layer 6 by the plurality of parallel laser beams 53, ... When burnt out (evaporated), the metal-free zone 10, ... With a width much narrower than that provided on a commercially available web can be formed with extremely high precision. This naturally leads to a reduction in the size of the capacitor itself and a saving of materials. The tension sensing and guidance adjustment system adopted in the prototype of the applicant is the Advanced Web Systems, Inc., a U.S. company.
Obtained from.

[0023]

In the multilayer capacitor (stacked type capacitor) manufactured according to the manufacturing method of the present invention, the alternately laminated structure portion serving as the active region or effective capacitor region of the capacitor, that is, the sheet belonging to the first group. -Shaped dielectric layers and sheet-shaped dielectric layers belonging to the second group are alternately laminated one by one, and the metal layers formed on the respective dielectric layers are adjacent to each other. In the part of the structure where the dielectric layer is sandwiched between them, the metal layers belonging to the first group and the dielectric layers are displaced from each other by a predetermined dimension in the width direction with respect to the metal layers belonging to the second group. Each metal layer is always on the part where each dielectric layer projects outward in the width direction with respect to the dielectric layer of the other group, while on the other hand, above or below the projecting part. Of the other party The collector layer, rather than the metal layer of the other party, faces the edge metal band. The edge metal zone on each dielectric layer is, so to speak, a floating electrode. In other words, the edge metal band is not in electrical contact with the metal layer formed on the same dielectric layer at all, and the metal layer between the edge metal band and the metal layer is always in contact with each other. There is a metal-free zone not marked. Therefore, the capacitor terminal electrodes are formed from the respective end faces in the width direction with respect to the metal layer part formed on the dielectric layer part which is the part protruding outward in the width direction with respect to the group of the other party. When the metallic materials for contacting are deposited, not only when the respective metallic materials make electrical contact only with the corresponding metallic layers, but not with the counterparts located under the corresponding metallic layers. Even if it comes into contact with the edge metal zone belonging to the group, since there is a metal-free zone between this edge metal zone and the metal layer of the other party, on each dielectric layer of the first and second groups. The short circuit accident of the metal layers formed in the will never occur. In other words, even in the metal-free zone,
The metal material for forming the terminal electrodes does not enter.
And, such a short-circuit preventing action is remarkable when a metal spray method, which has been most apt to cause such a short-circuit accident in the past, is used as a method for depositing a metal material. Further, the metal-free zone on each dielectric layer provided as described above for ensuring insulation has a metal layer on one side in the width direction and an edge metal zone on the other side. Therefore, even when it is superposed on the other dielectric layer, it does not unexpectedly collapse. Therefore, the variation of the capacitance value can be suppressed to be small. As a matter of course, as described later in Examples, the metal-free zone sufficiently fulfills its insulating function even with an extremely narrow width.

Further, the capacitor manufacturing method of the present invention can manufacture the capacitor having the above-mentioned excellent internal structure simply, surely, and promptly even in comparison with the conventional method. In particular, the first group of dielectric layers and the second group of dielectric layers are the same by simply changing the cutting positions of the webs and shifting them by a predetermined dimension in the width direction when the webs are wound around a common drum. It can be obtained from the web of the configuration. Also, many capacitors can be manufactured at once. On the other hand, according to the capacitor manufacturing apparatus of the present invention, while using existing parts for each component,
It is possible to provide a device having an optimum configuration as a device for manufacturing the capacitor having the above-mentioned specific action or as a device for realizing the above manufacturing method.
In particular, by using two webs having the same structure, changing the cutting positions, and merely shifting them by a predetermined dimension in the width direction when laminating each other, the metal of the first and second groups required for the capacitor of the present invention is obtained. Not only can an alternate laminated structure of layered dielectric layers be easily obtained, but also a pair of pressure rollers function advantageously in order to maintain a predetermined shift width relationship and a dense laminated relationship regarding such an alternating laminated structure. Not only that, the first and second webs
In the web advancing path until they are drawn out from the respective supply rollers and wound up on the drum via the pressure roller, the predetermined idle positions are provided to the webs by the interposition of the first and second idler rollers. Since it is possible to apply the tension, the swelling and the like in progress are effectively prevented, and therefore the above-mentioned predetermined deviation width relationship is extremely well ensured. In addition, since each web can be cut into a plurality of strips at each cutting station while the webs are stretched, that is, in a state where the webs are not dangling, the cut strips can be prevented from wrinkling. , Very smooth cutting can be done. In the end, this leads to stabilization or improvement in quality of the finally obtained multilayer capacitor.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an embodiment of a manufacturing apparatus of the present invention suitable for manufacturing a multilayer capacitor.

2 is a diagram for explaining the configuration of a cutting station, FIG.
2 is a sectional view taken along line 2-2 shown in FIG.

FIG. 3 is an enlarged plan view showing a part of the structural portion shown in FIG. 2 in an enlarged manner to explain a web cutting position at a cutting station.

FIG. 4 is a cross-sectional view taken along line 4-4 shown in FIG. 3 and showing a cut portion of one cutter.

5 is an explanatory diagram schematically showing the stacking relationship of each strip when a cross section is taken along line 5-5 shown in FIG. 1. FIG.

FIG. 6 is a cross-sectional view of an alternate laminated structure of a portion manufactured according to the present invention and effectively functioning as a multilayer capacitor.

FIG. 7 is a schematic configuration diagram of a main part of an example of an apparatus required for applying an adhesive to a web.

FIG. 8 is an explanatory diagram of a case where a metal-free zone is formed on each web by a laser.

[Explanation of symbols]

 2 Supply Roller 4 Supply Roller 6 Dielectric Layer 8 Metal Layer 10 Metal-free Zone 12 Idler Roller 16 Pressure Roller 18 Strip 20 Rotating Drum 21 Cutter 24 Edge Metal Zone 40 Metal Material or Terminal Electrode A Web B Web

Claims (7)

[Claims] 1. A metal layer is formed on each surface,
It has a laminated structure formed by laminating a plurality of sheet-shaped dielectric layers which are independent layers from each other, and a pair of capacitor terminal electrodes with a plurality of metal layers independent of each other in the laminated structure. A method of manufacturing a multilayer capacitor which is electrically connected to one end of a dielectric layer; having a width and a predetermined dielectric constant in the width direction on one surface of a dielectric layer continuous in a length direction orthogonal to the width. A plurality of metal layers that are continuous in the lengthwise direction at intervals and each have a predetermined width are formed in a strip shape, and the adjacent metal layers of the plurality of strip-shaped metal layers each have a predetermined spacing. The first and second webs having a metal-free zone formed with no metal over the width thereof are provided with respect to the first web, and the plurality of metal-free zones formed on the first web. In the length direction at a position slightly separated from each of the metal bands on one side in the width direction. The second web is continuously cut, and the second web is continuous in the length direction at a position slightly apart from each of the plurality of metal-free zones formed in the second web on the other side in the width direction. Cutting the first and second webs into a plurality of strips by cutting the strips into a plurality of strips; and winding the first web composed of the plurality of divided strips on the same drum. The second web, which also comprises a plurality of strips, divided together with the plurality of strips of the first web, except that the widthwise one edge of each strip of the first web is the first strip. The first and second webs are wound on the drum in a state where they are offset from each other in the width direction so as to project outward in the width direction by a predetermined dimension beyond one end edge in the width direction on the same side of the two webs. Process; on the drum As a result of winding up the strips of the first and second webs together, a plurality of strips are formed adjacent to each other in the width direction around the drum, and the first and second strips are respectively formed in the radial direction of the drum. Removing from the drum each of a plurality of rings comprising an alternating laminated structure in which strips of two webs are alternately laminated over a plurality of layers; and to the widthwise end faces of the alternating laminated structure of each ring. A step of adhering a metal material forming each of the terminal electrodes, and a step of cutting the alternating laminated structure with the terminal electrodes at a plurality of locations parallel to the width direction. Method for manufacturing multilayer capacitor. 2. The step of winding each strip group of the first and second webs together on the drum further comprises projecting the strip layers in the metal layer of each strip group outward in the width direction. The method of manufacturing a multilayer capacitor according to claim 1, further comprising the step of applying an adhesive on the surface of the non-existing portion. 3. A metal layer is formed on each surface,
It has a laminated structure formed by laminating a plurality of sheet-shaped dielectric layers which are independent layers from each other, and a pair of capacitor terminal electrodes with a plurality of metal layers independent of each other in the laminated structure. An apparatus for producing a multilayer capacitor electrically connected to one side of the first and second webs having a metal layer on one surface of a dielectric layer having a width and continuous in the length direction. And first and second supply rollers on which is wound in advance; only one of the first and second webs respectively drawn out from the first and second supply rollers is selectively
Or both of them, a rotary drum which is wound up together in a state of being overlapped with each other; and the first and second webs drawn from the first and second supply rollers are in contact with the rotary drum, respectively. First and second pressurizing the respective webs against the surface of the rotating drum so that the second webs are wound around the rotating drum while maintaining a state where they are displaced from each other by a predetermined dimension in the width direction. A pressure roller, which is located between the first and second pressure rollers and the first and second supply rollers, and which applies tension to the first and second webs. A second idler roller; the metal layer on the dielectric layer of the first web is arranged side by side in the width direction on the first pressure roller or immediately before the first pressure roller. Gold-free on the dielectric layer divided into metal strips A first cutting station for continuously cutting the first web in the length direction at a position slightly apart from one side in the width direction for each of the bands, and dividing the first web into a plurality of strips; On the second pressure roller or immediately before the second pressure roller, the metal layer on the dielectric layer of the second web is divided into a plurality of strip-shaped metal layers arranged in the width direction. For each of the plurality of metal-free zones on the dielectric layer, the second web is continuously cut in the lengthwise direction at a position slightly separated from the other side in the width direction to form a plurality of strips. A second cutting station to divide into;
As a result of winding the strips of the first and second webs together on the drum, a plurality of strips are formed adjacent to each other in the width direction around the drum, and each of the strips is formed in the radial direction of the drum. After removing from the drum a plurality of rings having an alternating laminated structure in which the strips of the first web and the strips of the second web are alternately laminated in a plurality of layers, each of the alternating laminated structures of the rings is removed. A device for adhering the metal material forming each of the terminal electrodes to both end faces in the width direction; a device for cutting the alternating laminated structure with the terminal electrodes at a plurality of positions parallel to the width direction; An apparatus for manufacturing a multilayer capacitor, comprising: 4. An adhesive agent is applied on the metal layer of each strip group before the first and second webs divided into the strip groups pass on the first and second pressure rollers, respectively. The apparatus for manufacturing a multilayer capacitor according to claim 3, further comprising an attached device. 5. A first and a second tension sensing roller for sensing the tension of each web are provided between the first and second supply rollers and the first and second pressure rollers, respectively, and 5. The apparatus for manufacturing a multilayer capacitor according to claim 3, further comprising a device that adjusts the tension of each web based on the tension sensed by the first and second tension sensing rollers. 6. A plurality of strip-shaped metal layers in which the metal layers on the dielectric layers are arranged side by side in the width direction on each of the first and second webs before cutting by each of the cutting stations. Each of the plurality of metal-free zones on the dielectric layer, which is divided into, is already formed when the webs are wrapped around the first and second feed rollers;
6. The apparatus for manufacturing a multilayer capacitor according to claim 3, 4, or 5. 7. A plurality of strip-shaped metal layers in which the metal layers on the dielectric layers are arranged side by side in the width direction on each of the first and second webs before cutting by each cutting station. A plurality of metal-free zones on the dielectric layer, each of which is divided into, are formed in series on the dielectric layer of each web before the web passes through the cutting stations. 6. The laser device for removing the metal material from the metal layer at predetermined intervals in the width direction and continuously in the length direction over the predetermined width, respectively. Manufacturing equipment for multilayer capacitors.