WO2017208610A1 - Wound type film capacitor and method for manufacturing same - Google Patents

Abstract

A wound type film capacitor 1 according to the present invention is provided with a wound body 2 in which a first and a second electrically conductive layer 5, 6 and a first and a second insulating film 7, 8 are wound in a roll in an overlapping state in the order of the first electrically conductive layer 5, the first insulating film 7, the second electrically conductive layer 6, and the second insulating film 8. At least the first insulating film 7 is a glass film, and the wound body 2 has a through-hole 10 provided at the center thereof that penetrates through the wound body 2 in a width direction thereof.

Description

Winding type film capacitor and manufacturing method thereof

The present invention relates to a wound film capacitor and a manufacturing method thereof.

For example, in an electric vehicle (EV) and a hybrid electric vehicle (HEV), an inverter is used to drive the AC motor by converting the DC power of the battery into AC power. A DC power supply circuit (converter, battery, etc.) connected to the inverter switching circuit is generally called a DC link, and the DC power supply voltage is called a DC link voltage. A large-capacitance capacitor called a DC link capacitor is connected to the DC link of the inverter in parallel with the DC power supply to compensate for an instantaneous load fluctuation caused by the switching circuit (see, for example, Patent Document 1).

Capacitors used for this purpose are required to have the following characteristics.
(1) The ability to instantaneously store and release large amounts of energy to compensate for instantaneous load fluctuations,
(2) In order to prevent a situation where the circuit does not operate properly due to a temperature change, the temperature dependence of the dielectric constant is small, and (3) it operates normally even in a high temperature environment.

JP-T-2004-52496 Gazette

At present, ceramic capacitors using BaTiO ₃ are mainly used as capacitors for this purpose. However, this ceramic capacitor has a problem that dielectric breakdown occurs when a high voltage is applied. The reason is that when the convex portions of the crystal grains present in the ceramic capacitor are in contact with the electrode and a high voltage is applied to the contact portion, electric field concentration occurs and a short circuit is likely to occur.

Further, it is known that a ceramic capacitor using BaTiO ₃ has a large temperature dependence of dielectric constant, and the dielectric constant is likely to change due to temperature change. For this reason, in order to reduce the temperature dependence of the dielectric constant, it has been studied to dope Mg, Mn, or the like into BaTiO ₃ . However, when doped with Mg and Mn, etc., a charge relatively -2 crystal lattice of BaTiO ₃ is induced, whereby there is a case where an oxygen defect is generated in BaTiO _3. This oxygen defect may cause a decrease in dielectric constant under a DC voltage. Therefore, in a ceramic capacitor using BaTiO ₃ , it is difficult to reduce the temperature dependence of the dielectric constant while increasing the dielectric constant.

In order to store a large amount of energy in the capacitor, it is necessary to secure a large area per unit volume. For example, a large area can be secured by adopting a structure in which plate-shaped ceramic materials are laminated. However, this method increases the number of parts and complicates the process, resulting in an increase in cost.

In order to increase the capacity, for example, it is conceivable to construct a capacitor by winding a resin film as an insulator together with a metal film in a roll shape. In order to guarantee use in a high temperature environment such as in-vehicle equipment, it is necessary to install a cooling device adjacent to the capacitor. In this case, even if the capacitor can be reduced in size, the required installation space is increased as much as the cooling device. As a result, it is difficult to say that it is preferable for reducing the size of the capacitor.

The characteristics described above are generally intended to improve the general versatility of capacitors. However, as described above, capacitors that are difficult to increase in capacity and have problems with high-temperature environment characteristics hinder the miniaturization of capacitors, resulting in As a result, it has been difficult to generalize capacitors.

In view of the above circumstances, in the present specification, the technology to be solved by the present invention is to provide a capacitor having excellent versatility by increasing capacity and improving high-temperature environment characteristics while avoiding an increase in size. As an objective.

The solution to the technical problem is achieved by the wound film capacitor according to the present invention. That is, in this capacitor, the first and second conductive layers and the first and second insulating films are the first conductive layer, the first insulating film, the second conductive layer, and the second insulating film. A wound film capacitor having a wound body that is wound into a roll shape in the state of overlapping in the order of at least the first insulating film is a glass film, and the center of the wound body In addition, it is characterized by the fact that a through-hole penetrating the wound body in the width direction is provided. In the present specification, the width direction of the wound body is a direction orthogonal to both the longitudinal direction and the thickness direction of the first or second insulating film in a state constituting the wound body. Means. *

Thus, in the present invention, the first and second insulating films and the first and second conductive layers are alternately wound in a roll shape with the first and second conductive layers overlapping each other. In addition, at least the first insulating film was a glass film. Since glass is unlikely to generate oxygen vacancies, the temperature dependence of the dielectric constant can be reduced without reducing the dielectric constant. Therefore, by configuring the capacitor with a wound body in the form of a roll of a film made of glass and a conductive layer, while increasing the capacitance per unit volume of the capacitor, due to temperature changes, The situation where the circuit does not operate properly can be effectively prevented. Therefore, a capacitor capable of storing a large amount of energy and excellent in high temperature environmental characteristics can be manufactured in a relatively small size.

Further, in the present invention, a through hole that penetrates the wound body in the width direction is provided at the center of the wound body constituting the capacitor. With this configuration, a hollow space exists in the center of the capacitor over the entire width direction. For example, if the core used for winding the insulating film remains in the center of the wound body, depending on the material of the core, when the wound body operates like a kind of coil, Inductance may increase due to the influence. This kind of increase in inductance is not preferable because it causes an increase in impedance particularly in a high frequency range. In this regard, by providing a through hole in the center of the wound body as described above, air as an insulator exists inside the wound body, so that an increase in inductance as described above is suppressed. It is possible to avoid as much as possible an increase in impedance in the high frequency range. Of course, if the center of the wound body is a hollow space, the weight of the capacitor can be reduced by that amount, which is suitable for general use of the capacitor.

Further, the wound film capacitor according to the present invention may be a glass film as the second insulating film.

Thus, by using the second insulating film as a glass film, the wound body can be composed of two glass films and two conductive layers disposed therebetween. As a result, the capacitor can be a completely inorganic film capacitor that does not contain an organic substance, so that the heat resistance of the capacitor can be increased. Therefore, the function as a capacitor can be appropriately exhibited without being affected by the ambient temperature and other environments.

Further, in the wound film capacitor according to the present invention, the first and second conductive layers are both metal films, and the first and second metal films are in opposite directions in the thickness direction of the first insulating film. The film may be formed on the first surface and the second surface that face each other.

By integrating the conductive layer with the insulating film in this way, the adhesion between the insulating film and each conductive layer is increased, so that the distance between the conductive layers serving as positive and negative electrodes can be reduced, and the capacitance is further improved. Can be achieved. In addition, when the conductive layer is a film, the thickness dimension can be set without considering the handleability of the conductive layer alone, so the metal film thickness can be made smaller and further miniaturization can be achieved. It becomes possible to plan.

Alternatively, in the wound film capacitor according to the present invention, the first and second conductive layers are both metal films, and the first metal film is directed to the first surface that faces one of the thickness directions of the first insulating film. It may be formed, and the second metal film may be formed on the third surface directed in one thickness direction of the second insulating film.

Also by integrating the conductive layer and the insulating film with this configuration, the adhesion between the insulating film and the conductive layer can be increased and the distance between the conductive layers can be reduced, thereby further improving the capacitance. It becomes possible. In addition, since one conductive layer (metal film) may be formed per one insulating film, depending on conditions, the thickness dimension of the insulating film is smaller than when two conductive layers are provided on one insulating film. it can. This can be expected to further improve the capacitance.

In addition, the wound film capacitor according to the present invention has a first side end face in which the first conductive layer faces one side in the width direction of the wound body and a second side end face in which the other side in the width direction faces. And the second conductive layer has a third side end face that faces one side in the width direction of the wound body, and a fourth side end face that faces the other side in the width direction. The side end face is offset to one side in the width direction of the wound body from the fourth side end face of the second conductive layer, and the third side end face of the second conductive layer is It may be offset from the first side end surface of the layer to the other side in the width direction of the wound body.

By comprising in this way, when the electrode (positive electrode, negative electrode) is provided on both sides in the width direction of the wound body, the conductive layer on the side to be connected can be easily identified. Can be reliably avoided, and electrical connection between each electrode and the conductive layer on the side to be connected to each electrode can be easily and safely performed.

Further, the wound film capacitor according to the present invention is provided with a first electrode in contact with the first conductive layer and separated from the second conductive layer on one side in the width direction of the wound body, and A second electrode that is in contact with the second conductive layer and is separated from the first conductive layer may be provided on the other side in the width direction of the wound body.

By arranging the electrodes in this way, electrical connection between the corresponding conductive layer and the electrodes can be performed with a simple structure. In particular, as described above, each conductive layer is arranged in an offset (shifted) direction different from each other in the width direction of the wound body, so that the gap between the electrode and the conductive layer on the non-connecting side that does not correspond to this electrode. In a state having a predetermined gap in the width direction. Therefore, it is possible to easily form a state in which only the conductive layer on the side to be connected is in contact with, without particularly making the electrode in a complicated shape (such as a partially protruding shape).

Further, the wound film capacitor according to the present invention may be one in which the surfaces of the glass films are in direct contact with each other at the end in the longitudinal direction on the winding end side of the glass film. The surfaces of the glass films referred to here include the meanings of both the two surfaces included in one glass film and the surfaces of two different glass films.

Thus, in the longitudinal direction end on the winding end side of the glass film constituting the wound body, by taking a form in which the surfaces of the glass films are brought into direct contact with each other without using an adhesive or the like, A glass film as an insulating film can be fixed at the end of the winding end. Therefore, the shape of the wound body obtained by winding the two insulating films including the glass film into a roll can be appropriately maintained. Moreover, since it is not necessary to interpose the element for fixing the surfaces of a glass film, a winding body can be comprised simply and can be reduced in size.

In addition, the wound film capacitor according to the present invention may be one in which the surfaces of the glass films are in direct contact with each other at the end in the longitudinal direction on the winding start side of the glass film. In addition, the meanings of both of the two surfaces contained in one glass film and the one surfaces of two different glass films are also included in the surfaces of the glass films referred to herein. *

In this way, at the end of the glass film constituting the wound body in the longitudinal direction end on the winding start side, the glass film surfaces are directly brought into close contact with each other, so that the glass at the end of the winding start side is taken. The film can be fixed. Accordingly, it is possible to appropriately maintain the shape of the wound body (part of) during winding of the two insulating films including the glass film into a roll shape, or the shape of the wound body wound up. it can. Also in this case, since it is not necessary to interpose an element for fixing the surfaces of the two insulating film glass films, the wound body can be easily configured and can be downsized.

Further, in the wound film capacitor according to the present invention, the thickness of the first insulating film may be set to 50 μm or less.

By setting the thickness dimension of the insulating film in this way, the area of the insulating film per unit volume is increased, so that the capacitance of the capacitor can be increased. In addition, since the flexibility of the insulating film is improved, the minimum winding diameter of the wound body (see below for details) can be reduced. Therefore, this also makes it possible to increase the area of the insulating film per unit volume and improve the capacitance. In other words, it is possible to reduce the size of the capacitor while ensuring a predetermined capacitance.

Further, the wound film capacitor according to the present invention may have a minimum winding diameter of 100 mm or less. The minimum winding diameter of the wound body here is substantially equal to the inner diameter dimension of the wound body, and among the first and second insulating films that are wound in a roll shape. It means the radius of curvature of the insulating film located at the innermost radial direction.

Thus, the capacitor can be effectively reduced in size by winding the insulating film so that the minimum winding diameter of the wound body becomes a certain value or less.

Further, the wound film capacitor according to the present invention may be one in which the longitudinal dimension of the first insulating film is set to 0.05 m or more.

Thus, by defining the lengthwise dimension of the insulating film, the area (surface area) of the conductive layer that is usually set to the same size as the insulating film or slightly smaller (size in the lengthwise direction). Can be secured. Therefore, it is possible to provide the capacitor with a capacitance corresponding to the area of the conductive layer.

Further, in the wound film capacitor according to the present invention, a value obtained by dividing the width dimension of the first insulating film by the thickness dimension of the first insulating film may be set to 1000 or more.

For the same reason as described above, the capacitance of the capacitor increases as the area (surface area) of the insulating film increases and the thickness dimension decreases. Therefore, by setting the ratio of the dimension in the width direction to the thickness dimension of the insulating film to be 1000 or more, it is possible to ensure the level of capacitance required for this type of capacitor.

Further, the wound film capacitor according to the present invention may be one in which the relative dielectric constant of the glass film as the first insulating film is set to 5.0 or more. Here, the relative dielectric constant refers to a value measured by a method based on ASTM D150 at a temperature of 25 ° C.

In addition, the wound film capacitor according to the present invention may be one in which the arithmetic average roughness Ra of the first or second surface of the first insulating film is set to 5 nm or less. In addition, arithmetic mean roughness Ra here refers to the value measured by the method based on JISB0601: 2001.

Thus, by defining the arithmetic average roughness Ra of the surface of the insulating film, the voltage causing dielectric breakdown increases, so that a large amount of energy can be stored accordingly.

In the wound film capacitor according to the present invention, the first insulating film is SiO ₂ : 20 to 70%, Al ₂ O ₃ : 0 to 20%, B ₂ O ₃ : 0 to 17 in mass%. %, MgO: 0 to 10%, CaO: 0 to 15%, SrO: 0 to 15%, BaO: 0 to 40%.

By setting the glass composition in this manner, devitrification is less likely to occur at the time of molding, so that the insulating film (glass film) having a large width direction dimension and a long direction dimension can be easily formed. Therefore, as a result, it is possible to efficiently manufacture a capacitor capable of storing a large amount of energy.

The solution to the above problem can also be achieved by the method for manufacturing a wound film capacitor according to the present invention. That is, in this manufacturing method, the first and second conductive layers, and the first and second insulating films in which at least the first insulating film is a glass film, the first conductive layer, the first insulating film, A step of superposing the second conductive layer and the second insulating film in this order to form a laminated body of insulating films; a step of winding the laminated body around the core to form a wound body; and The step of forming a through-hole penetrating the wound body in the width direction at the center of the wound body is characterized.

According to the manufacturing method of the present invention, since at least the first insulating film of the first and second insulating films is a glass film, as described above, the temperature of the dielectric constant without reducing the dielectric constant. The dependency can be reduced. Therefore, this glass film is overlapped with the conductive layer to form a laminate, and the laminate is wound around the core to form a wound body, thereby increasing the capacitance per unit volume of the capacitor. However, it is possible to effectively prevent a situation in which the circuit does not operate properly due to a temperature change. Therefore, a capacitor capable of storing a large amount of energy and excellent in high temperature environmental characteristics can be manufactured in a relatively small size.

Further, in the manufacturing method according to the present invention, the wound body is formed by removing the core from the wound body after the laminated body of the insulating film and the conductive layer described above is wound around the core to form the wound body. A through hole penetrating the wound body in the width direction was formed at the center. With this configuration, as described above, a hollow space exists in the center of the capacitor over the entire width direction. Therefore, as compared with the case where the capacitor is configured with the core remaining in the center of the wound body, it is possible to suppress an increase in inductance and avoid an increase in impedance in a high frequency region as much as possible.

Moreover, the manufacturing method of the winding type film capacitor which concerns on this invention is the 1st and 2nd on the 1st surface and 2nd surface which orient as the 1st insulating film and the direction which opposes in the thickness direction. After preparing what each formed the 1st and 2nd metal film as a conductive layer, the 1st insulating film in which the 1st and 2nd metal film was formed, and the 2nd insulating film A laminate may be formed by overlapping.

Thus, by preparing an insulating film in which two metal films are formed on both surfaces in advance as the first insulating film, the second insulating film is not integrally formed with any member, for example. It can be composed of a single glass film. This makes it possible to configure the capacitor with a simple structure while reducing the production cost of the second insulating film.

Further, the capacitor manufacturing method according to the present invention includes a core composed of a plurality of divided bodies each having a winding surface of a laminate on the outer periphery, and a connecting member that connects the plurality of divided bodies. After preparing and winding a laminated body around a core in a state where a plurality of divided bodies are connected by a connecting member to form a wound body, after removing a connecting member and eliminating a connected state between the plurality of divided bodies Alternatively, a part of the plurality of divided bodies may be removed from the wound body, and then the remaining portions of the plurality of divided bodies may be removed.

When the insulating film constituting the wound body is, for example, a resin film, after the wound body is formed, the wound body is fixed and a force is applied to the core in the axial direction (width direction of the wound body). Although the method of removing a core by this can be considered, when a winding body is comprised with the glass film, when a method as mentioned above is employ | adopted, a possibility that a glass film may be damaged increases. On the other hand, according to the manufacturing method according to the present invention, the core can be divided and removed in stages (extracted), so that the core can be removed without applying unnecessary force to the glass film. . Moreover, since it is set as the state which mutually connected the some division body by the connection member at the time of winding, the positional accuracy of a winding surface can be ensured and a laminated body can be wound up. Therefore, the wound body can be formed with high accuracy without the risk of damage described above.

As described above, according to the present invention, it is possible to provide a capacitor with excellent versatility by increasing the capacity and improving the high-temperature environment characteristics while avoiding an increase in size.

1 is a perspective view of a wound film capacitor according to a first embodiment of the present invention. It is a perspective view which shows the state which expanded a part of winding body shown in FIG. 1 virtually. It is sectional drawing of the capacitor | condenser shown in FIG. It is a figure for demonstrating an example of the manufacturing method of the capacitor | condenser shown in FIG. 1, Comprising: It is a disassembled perspective view which illustrates notionally the process of forming the laminated body of an insulating film. It is a perspective view of a laminated body. It is a perspective view of the core used for winding of a laminated body. It is a disassembled perspective view of the core used for winding of a laminated body. It is a figure for demonstrating an example of the winding aspect of a laminated body, Comprising: The figure which looked at the state of winding start of a laminated body from the direction along the winding centerline, and its principal part enlarged view. It is a figure for demonstrating an example of the winding aspect of a laminated body, Comprising: The figure which looked at the state of winding end of a laminated body from the direction along the winding centerline, and its principal part enlarged view. It is a perspective view of the winding body of the state which rolled up the laminated body around the core and integrated with the core. It is a perspective view of the winding body which shows the state which removed a part of core from the winding body. It is a perspective view which shows the state which expanded a part of winding body which concerns on 2nd embodiment of this invention virtually. It is a perspective view showing the state where a part of modification of the winding object concerning a second embodiment of the present invention was developed virtually. It is a figure for demonstrating an example of the winding aspect of the winding body which concerns on 3rd embodiment of this invention, Comprising: It is the figure which looked at the winding body in winding from the direction along the centerline. It is a figure for demonstrating an example of the winding mode shown in FIG. 14, Comprising: The figure which looked at the state of the winding start of both insulating films from the direction along the winding centerline, and its principal part enlarged view is there. It is a figure for demonstrating an example of the winding mode shown in FIG. 14, Comprising: The figure which looked at the state of the winding end of both insulating films from the direction along the winding centerline, and its principal part enlarged view is there. It is the figure which looked at the wound body which concerns on 4th embodiment of this invention from the direction along the centerline. It is the figure which looked at the winding body which concerns on 5th embodiment of this invention from the direction along the centerline. Sample No. of Example 2 is a graph showing measurement results of impedance of a wound film capacitor according to 1;

Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.

FIG. 1 is a perspective view of a wound film capacitor 1 according to a first embodiment of the present invention. The capacitor 1 includes a wound body 2 and positive and negative electrodes 3 and 4 that are in contact with the wound body 2 in the width direction. Lead electrodes (not shown) are attached to the electrodes 3 and 4 so that a predetermined voltage can be applied between the electrodes 3 and 4. Hereinafter, the configuration of the wound body 2 will be mainly described.

As shown in FIG. 2, the wound body 2 includes first and second conductive layers 5 and 6 and first and second insulating films 7 and 8, and these two conductive layers 5 and 6. 6 and the two insulating films 7 and 8 are stacked in the order of the first conductive layer 5, the first insulating film 7, the second conductive layer 6, and the second insulating film 8 in the form of a roll. Shape. In the present embodiment, the first and second conductive layers 5 and 6 are both metal films, and the first surface 7 a and the second surface are oriented in opposite directions in the thickness direction of the first insulating film 7. 7b, respectively. Thus, the two conductive layers 5 and 6 are both integrated with the first insulating film 7.

Of the two insulating films 7 and 8, at least the first insulating film 7 is a glass film. In the present embodiment, the two conductive layers 5 and 6 are integrated with the glass film (first insulating film 7). The details of the glass composition that can be used will be described later.

The thickness t1 (see FIG. 2) of the glass film as the first insulating film 7 is set to 50 μm or less, preferably 40 μm or less, more preferably 30 μm or less, and further 20 μm or less. It is suitably set in the order of 10 μm or less, 8 μm or less, 6 μm or less, 5 μm or less, 3 μm or less, and particularly preferably 1 μm or less. The smaller the thickness dimension t1 of the first insulating film 7, the larger the area per unit volume in the state in which the insulating film 7 is wound, so that a large amount of energy can be easily stored. Moreover, since the flexibility of the 1st insulating film 7 improves, so that the thickness dimension t1 is small, the minimum curvature radius (minimum winding diameter) of the said insulating film 7 can be made small to the level mentioned later.

Also, as the second insulating film 8, for example, a resin, paper, or glass film can be used, and among these, a glass film (that is, a glass film) can be suitably used. By using a glass film for the second insulating film 8 as well, it is possible to eliminate the so-called organic matter and form the wound body 2 with only the inorganic material, so that the heat resistance of the wound film capacitor 1 is improved. It can be easily increased. Here, when using a glass film for the 2nd insulating film 8, the thickness dimension t2 (refer FIG. 2) of the said glass film (2nd insulating film 8) is the glass film as the 1st insulating film 7, and Similarly, it is set to 50 μm or less, preferably set to 40 μm or less, more preferably set to 30 μm or less, more preferably 20 μm or less, 10 μm or less, 8 μm or less, 6 μm or less, 5 μm or less, 3 μm or less. And particularly preferably 1 μm or less. Of course, a resin film can also be used for the second insulating film 8. In this case, the resin film functions as an insulator and also functions as a buffer material. Therefore, it is possible to effectively avoid a situation in which the glass film is damaged when the both insulating films 7 and 8 are wound up.

The first conductive layer 5 is in a direction opposite to the first side end face 5a and the first side end faces 5a and 6a directed to one side in the width direction of the wound body 2 (left side in FIG. 3). It has the 2nd side end surface 5b which faces the other (the right side in FIG. 3) of the width direction of the wound body 2. As shown in FIG. The second conductive layer 6 has a third side end face 6 a that faces one side in the width direction of the wound body 2 and a fourth side end face 6 b that faces the other side in the width direction of the wound body 2. . In the present embodiment, the second side end face 5b of the first conductive layer 5 is offset to one side in the width direction from the fourth side end face 6b of the second conductive layer 6, and the second side end face 5b is offset. The third side end face 6 a of the conductive layer 6 is offset to the other side in the width direction from the first side end face 5 a of the first conductive layer 5. Further, the first conductive layer 5 is offset in one direction, i.e., in the thickness direction of the first insulating film 7 (here, the first conductive layer 5 is formed) of the first surface 7a of the first surface 7a. The width direction dimension d1 of the region where the conductive layer 5 is not formed is set to, for example, 1 mm or more, preferably 2 mm or more, and more preferably 3 mm or more. Similarly, the second surface 7b of the second surface 7b is directed to the other in the thickness direction of the first insulating film 7 (here, the second conductive layer 6 is formed), which is an offset amount of the second conductive layer 6. The width direction dimension d2 of the region where the second conductive layer 6 is not formed is set to 1 mm or more, preferably 2 mm or more, and more preferably 3 mm or more. In this way, even if the laminated body 9 is displaced in the width direction due to the winding mode of the laminated body 9 (see FIGS. 4 and 5) described later, the first conductive layer 5 and the first conductive layer 5 The situation where the second electrode 4, the second conductive layer 6 and the first electrode 3 are electrically connected can be effectively avoided. Of course, although not shown in the drawings, the first surface 7a and the second surface 7b of the first insulating film 7 are equivalent to the conductive layers 5 and 6 in regions where the conductive layers 5 and 6 are not formed. An insulating film having a thickness dimension may be formed.

Note that various materials can be used for the conductive layers 5 and 6 (metal films). For example, from the viewpoint of cost and conductivity, one or more metals selected from the group consisting of Al, Pt, Ni, Cu, Ag, and an Ag alloy can be suitably used. It shows better heat resistance than the simple substance. Further, as in the present embodiment, when the conductive layers 5 and 6 are formed as metal films on the surfaces 7a and 7b of the first insulating film 7 (glass film), known film forming means can be applied. is there.

Moreover, in this embodiment, the width direction dimension w2 of the 2nd insulating film 8 in which the conductive layers 5 and 6 are not formed is larger than the width direction dimension w1 of the 1st insulating film 7, as shown in FIG. The first insulating film 7 is small and disposed so as to protrude from the second insulating film 8 to the outside in the width direction. In this way, it is possible to avoid the state in which the second insulating film 8 protrudes in the width direction of the wound body 2 rather than the conductive layers 5 and 6. Can be easily formed.

The first electrode 3 serving as a positive electrode or a negative electrode is disposed on one side in the width direction of the wound body 2 (left side in FIG. 3). At this time, the first electrode 3 is electrically connected to the first conductive layer 5 adjacent in the thickness direction (vertical direction in FIG. 3) through the first insulating film 7 in the wound body 2. In contact with the first side end face 5a of the first conductive layer 5 and away from the third side end face 6a of the second conductive layer 6 so as to be insulated from the second conductive layer 6. Yes (not touching). The second electrode 4 is disposed on the other side in the width direction of the wound body 2 (on the right side in FIG. 3), is electrically connected to the second conductive layer 6, and is electrically connected to the first conductive layer. It is in contact with the fourth side end face 6b of the second conductive layer 6 and is separated (not in contact) with the second side end face 5b of the first conductive layer 5 so as to be insulated from the layer 5. .

As the electrodes 3 and 4, various materials can be used. For example, from the viewpoint of cost and conductivity, one or more metals selected from the group consisting of Al, Pt, Ni, Cu, Ag, and an Ag alloy can be suitably used. It shows better heat resistance than the simple substance. The electrodes 3 and 4 are formed, for example, by applying a conductive paste containing the above metal powder (a paste-like conductive material having a predetermined viscosity) on both sides in the width direction of the wound body 2 and solidifying it. It is possible. Also, the form that can be taken in this case is not particularly limited, and may be annular as shown in FIG. 1, or may be layered as shown in FIG. Of course, as shown in FIG. 1 and FIG. 3, it may be annular and layered.

Further, the minimum winding diameter of the wound body 2 is set to, for example, 100 mm or less, preferably 80 mm or less, more preferably 75 mm or less, further 50 mm or less, 30 mm or less, 20 mm or less, 10 mm or less, 5 mm or less in this order. It is set suitably, and particularly preferably set to 3 mm or less. When the outer diameter dimension of the wound body 2 is constant, the smaller the minimum winding diameter, the larger the area per unit volume, which is suitable for applications that require storage of a large amount of energy.

The longitudinal dimension L1 (see FIG. 4) of the first insulating film 7 is set to, for example, 0.05 m or more, preferably 0.5 m or more, more preferably 1 m or more. For example, 3 m or more, 5 m or more, 10 m or more, 30 m or more, 50 m or more, and 70 m or more are preferably set, and particularly preferably 100 m or more. Thus, by setting the size of the longitudinal direction dimension L1 of the first insulating film 7, it becomes possible to ensure a level of capacitance required for a current circuit, for example.

Further, the width direction dimension w1 and the thickness dimension t1 are set such that the value obtained by dividing the width direction dimension w1 of the first insulating film 7 by the thickness dimension t1 is, for example, 1000 or more, and preferably 1200 or more. Preferably, the width direction dimension w1 and the thickness dimension t1 are suitably set in the order of 1600 or more, 1800 or more, 2000 or more, more preferably 1400 or more, and particularly preferably the width direction dimension w1 to be 2400 or more. A thickness dimension t1 is set. By setting both dimensions w1 and t1 so that the ratio between the width direction dimension w1 and the thickness dimension t1 is within the above range, for example, it is possible to ensure a level of capacitance required for a current circuit. It becomes.

In addition, the relative dielectric constant of the first insulating film 7 is set to, for example, 5 or more, preferably 5.5 or more, more preferably 6 or more, and further 7 or more, 8 or more, 9 As described above, it is preferably set in the order of 10 or more, particularly preferably 11 or more. By using the first insulating film 7 (glass film) exhibiting a relative dielectric constant in the above-described range, it is possible to ensure a level of capacitance required for a current circuit, for example.

The arithmetic average roughness Ra of the first surface 7a (second surface 7b) of the first insulating film 7 is set to, for example, 5 nm or less, preferably 3 nm or less, more preferably 1 nm or less, Furthermore, it is preferably set in the order of 0.8 nm or less, 0.4 nm or less, and 0.3 nm or less, and particularly preferably 0.2 nm or less. By setting the arithmetic average roughness Ra of the first surface 7a (second surface 7b) of the first insulating film 7 within the above range, the voltage that causes dielectric breakdown when a high voltage is applied is increased. be able to.

The maximum height Rmax of the first surface 7a (second surface 7b) of the first insulating film 7 is set to, for example, 10 nm or less, preferably 5 nm or less, and more preferably 3 nm or less. The By setting the maximum height Rmax of the first surface 7a (second surface 7b) of the first insulating film 7 within the above range, the voltage causing dielectric breakdown when a high voltage is applied is increased. be able to. In addition, the maximum height Rmax here refers to the value measured by the method based on JIS B0601: 2001.

In the present embodiment, the first insulating film 7 has a glass composition in mass%, for example, SiO ₂ : 20 to 70%, Al ₂ O ₃ : 0 to 20%, B ₂ O ₃ : 0 to 17%, MgO: 0 to 10%, CaO: 0 to 15%, SrO: 0 to 15%, BaO: 0 to 40%.

Hereinafter, the reason why the content of each component is defined in the above-described range will be described.

If the content of SiO ₂ exceeds the appropriate range and increases, the meltability and moldability may be reduced. For the above reasons, the content of SiO ₂ is set to 70% or less, preferably 65% or less, more preferably 60% or less, and further 58% or less, 55% or less, 50%. It is suitably set in the following order, particularly preferably 45% or less. On the other hand, if the SiO ₂ content falls outside the proper range, it becomes difficult to form a glass network structure, and vitrification may become difficult. For the above reasons, the content of SiO ₂ is set to 20% or more, preferably 25% or more, and particularly preferably 30% or more.

When the content of Al ₂ O ₃ is increased outside the proper range, devitrified crystals are likely to be deposited on the glass, and the liquidus viscosity is likely to be lowered. For these reasons, the content of Al ₂ O ₃ is set to 20% or less, preferably set to 18% or less, more preferably set to 15% or less, and further preferably set to 12% or less. Preferably, it is set to 10% or less. On the other hand, when the content of Al ₂ O ₃ falls outside the appropriate range and decreases, the balance of components of the glass composition is impaired and the glass tends to be devitrified, depending on the relationship with other components. For the above reasons, the Al ₂ O ₃ content is set to 0% or more, preferably 1% or more, more preferably 3% or more, and particularly preferably 5% or more.

If the content of B ₂ O ₃ increases outside the proper range, the dielectric constant tends to decrease, the heat resistance decreases, and the reliability of the wound film capacitor 1 in a high temperature environment may decrease. Arise. For the above reasons, the content of B ₂ O ₃ is set to 17% or less, preferably 15% or less, more preferably 13% or less, and further 11% or less, 7% or less. It is preferably set in order, and particularly preferably 5% or less.

MgO is a component that increases the strain point and decreases the high-temperature viscosity. However, when the content of MgO increases outside the appropriate range, the liquidus temperature, density, and thermal expansion coefficient tend to be excessively high. For the above reasons, the content of MgO is set to 10% or less, preferably 5% or less, more preferably 3% or less, more specifically 2% or less, 1.5% or less, 1 % Is preferably set in the order of% or less, and particularly preferably 0.5% or less.

When the content of CaO is outside the proper range and increases, the density and thermal expansion coefficient increase, and the component balance of the glass composition is impaired, and the glass tends to be devitrified. For these reasons, the CaO content is set to 15% or less, preferably 12% or less, more preferably 10% or less, still more preferably 9% or less, and particularly preferably 8%. Set to less than 5%. On the other hand, when the content of CaO falls outside the proper range, the dielectric constant and meltability tend to decrease. For these reasons, the content of CaO is set to 0% or more, preferably 0.5% or more, more preferably 1% or more, and further 2% to 3% in this order. And is preferably set to 5% or more.

If the SrO content is increased outside the appropriate range, the density and thermal expansion coefficient tend to increase. For the above reasons, the SrO content is set to 15% or less, preferably 12% or less. On the other hand, when the content of SrO falls outside the proper range, the dielectric constant and meltability tend to decrease. For the above reasons, the SrO content is set to 0% or more, preferably set to 0.5% or more, more preferably set to 1% or more, still more preferably set to 3% or more, particularly preferably. Is set to 5% or more.

When the content of BaO increases outside the appropriate range, the density and the thermal expansion coefficient tend to increase. For the above reasons, the BaO content is set to 40% or less, preferably 35% or less. On the other hand, when the content of BaO is less than the proper range and decreases, the dielectric constant decreases and it becomes difficult to suppress devitrification. For the above reasons, the content of BaO is set to 0% or more, preferably 0.5% or more, more preferably 1% or more, and further 2% or more, 5% or more, 10% % Or more, 15% or more, and 20% or more in order, particularly preferably 25% or more.

Each component of MgO, CaO, SrO, and BaO is a component that increases the dielectric constant, devitrification resistance, meltability, and moldability. However, if the content of MgO + CaO + SrO + BaO (total amount of MgO, CaO, SrO, BaO) decreases outside the appropriate range, it becomes difficult to increase the dielectric constant, and the function as a flux cannot be sufficiently exhibited. , The meltability tends to decrease. For the above reasons, the content of MgO + CaO + SrO + BaO is set to 5% or more, preferably 10% or more, more preferably 15% or more, and more preferably 20% or more and 25% or more in this order. And particularly preferably 30% or more. On the other hand, when the content of MgO + CaO + SrO + BaO increases outside the appropriate range, the density tends to increase, and the balance of the glass composition component is impaired, and conversely, devitrification resistance tends to decrease. For the above reasons, the content of MgO + CaO + SrO + BaO is set to 60% or less, preferably 55% or less, and more preferably 50% or less.

In addition to the above components, for example, the following components can be added to the glass composition within a range of appropriate content ratios.

Each component of Li ₂ O, Na ₂ O, and K ₂ O is a component that adjusts the thermal expansion coefficient by lowering the viscosity. However, if it is included in a large amount outside the appropriate range, a voltage that causes dielectric breakdown. Tends to decrease. In addition, the temperature characteristics of dielectric constant tend to decrease. For these reasons, when these components are added, the total amount is set to 15% or less, preferably 10% or less, more preferably 5% or less, and further to 2% or less, It is preferably set in the order of 1% or less and 0.5% or less, particularly preferably 1000 ppm or less.

ZnO is a component that increases the dielectric constant and also increases the meltability. However, if it is included in a large amount outside the appropriate range, devitrification of the glass tends to occur and the density tends to increase. For these reasons, the ZnO content is set to 0 to 40%, preferably 0 to 30%, more preferably 0 to 20%, and even more preferably 0.5 to 15%. Particularly preferably, it is set to 1 to 10%.

ZrO ₂ is a component that increases the dielectric constant. However, if the ZrO ₂ is contained outside the proper range and contained in a large amount, the liquidus temperature rises abruptly and zircon devitrified foreign matter tends to precipitate. For the above reasons, the content of ZrO ₂ is set to 20% or less, preferably 15% or less, and more preferably 10% or less. The ZrO ₂ content is set to 0.1% or more, preferably set to 0.5% or more, more preferably set to 1% or more, further preferably set to 2% or more, particularly preferably. Is set to 3% or more.

Each component of Y ₂ O ₃ , Nb ₂ O ₃ , and La ₂ O _{3 is} a component that increases the dielectric constant and the like, but if it is included in a large amount outside the appropriate range, the density tends to increase. For these reasons, when adding Y ₂ O ₃ , Nb ₂ O ₃ , or La ₂ O ₃ , the content of each component is preferably set to 20% or less.

The glass composition of the first insulating film 7 includes one or two selected from the group consisting of As ₂ O ₃ , Sb ₂ O ₃ , CeO ₂ , SnO ₂ , F, Cl, and SO ₃ as a fining agent. More than seeds can be added in the range of 0 to 3%. However, As ₂ O ₃ , Sb ₂ O ₃ , and F are preferably used as much as possible from an environmental viewpoint, and the content of each component is preferably set to less than 0.1%. From the environmental point of view, SnO ₂ , Cl and SO ₃ are preferable as the fining agent. The content of SnO ₂ + Cl + SO ₃ (the total amount of SnO ₂ , Cl and SO ₃ ) is set to 0.001 to 1%, preferably set to 0.01 to 0.5%, more preferably 0. It is set to 01 to 0.3%. The SnO ₂ content is set to 0 to 1%, preferably set to 0.01 to 0.5%, particularly preferably set to 0.05 to 0.4%.

Of course, components other than those described above can be added to the glass composition of the first insulating film 7 in a range of, for example, up to 20%, preferably up to 10%.

The liquid phase temperature of the first insulating film 7 is set to, for example, 1200 ° C. or less, preferably 1150 ° C. or less, more preferably 1090 ° C. or less, and further 1050 ° C. or less, 1030 ° C. or less. Is preferably set, particularly preferably 1000 ° C. or lower. If the liquid phase temperature of the first insulating film 7 is too high, the glass tends to be devitrified during molding, and it becomes difficult to improve the surface accuracy (surface roughness, etc.) of the first insulating film 7. is there. Further, the liquid phase viscosity of the first insulating film 7 is set to, for example, 10 ^3.5 dPa · s or more, preferably 10 ^4.0 dPa · s or more, more preferably 10 ^4.5 dPa · s or more, Preferably it is set to 10 ^4.8 dPa · s or more, particularly preferably 10 ^5.0 dPa · s or more. This is because if the liquid phase viscosity of the first insulating film 7 is too low, devitrification of the glass tends to occur during molding, and it becomes difficult to increase the surface accuracy of the first insulating film 7. Here, the liquid phase viscosity refers to a value obtained by measuring the viscosity of glass at the liquid phase temperature by a platinum ball pulling method. The liquid phase temperature passes through a standard sieve 30 mesh (about 500 μm), the glass powder remaining in 50 mesh (about 300 μm) is placed in a platinum boat and held in a temperature gradient furnace for 24 hours, and crystals precipitate. Refers to the value measured temperature.

For example, the density of the first insulating film 7 is set to 4.5 g / cm ³ or less, preferably set to 4.0 g / cm ³ or less, more preferably set to 3.6 g / cm ³ or less. For example, it is suitably set in the order of 3.3 g / cm ³ or less, 3.0 g / cm ³ or less, and 2.8 g / cm ³ or less, particularly preferably 2.5 g / cm ³ or less. The smaller the density, the easier it is to reduce the weight of the wound film capacitor 1. In addition, the density here refers to the value measured by the well-known Archimedes method.

The thermal expansion coefficient of the first insulating film 7 is set to, for example, 25 × 10 ⁻⁷ to 120 × 10 ⁻⁷ / ° C., preferably set to 30 × 10 ⁻⁷ to 120 × 10 ⁻⁷ / ° C., and more preferably. Is set to 40 × 10 ⁻⁷ to 110 × 10 ⁻⁷ / ° C., more preferably 60 × 10 ⁻⁷ to 100 × 10 ⁻⁷ / ° C., and particularly preferably 70 × 10 ⁻⁷ to 95 × 10. ^-7 / ℃ is set. If the coefficient of thermal expansion of the first insulating film 7 is set in the above range, the coefficient of thermal expansion of the first insulating film 7 and the surfaces 7a and 7b of the first insulating film 7 are formed by film formation or the like. Since the thermal expansion coefficients of the conductive layers 5 and 6 can be matched (approached), deformation of the conductive layers 5 and 6 such as warpage can be prevented. The coefficient of thermal expansion here refers to an average value measured with a dilatometer in the range of 30 to 380 ° C.

The temperature at 10 ^2.5 dPa · s of the first insulating film 7 is set to 1550 ° C. or lower, preferably 1450 ° C. or lower, more preferably 1350 ° C. or lower, and further 1250 ° C. or lower. It is suitably set in the order of 1200 ° C. or lower and 1170 ° C. or lower, particularly preferably 1150 ° C. or lower. The lower the temperature at 10 ^{2. 5} dPa · s of the first insulating film 7, it becomes easy to melt the glass at a low temperature, it is possible to reduce the production cost of the glass film. Here, the temperature at 10 ^2.5 dPa · s indicates a value measured by a platinum ball pulling method.

At least part of the surface 7a (7b) of the first insulating film 7 may be in an unpolished state. Moreover, in that case, it is preferable that all of the first surface 7a and the second surface 7b directed in opposite directions are unpolished. Although the theoretical strength of glass is very high, in fact, it often breaks at much lower stresses than the theoretical strength. This is because a small defect called Griffith flow is generated on the surface of the glass in a post-molding process such as a polishing process. Therefore, if the first surface 7a (second surface 7b) of the first insulating film 7 which is a glass film is unpolished, in other words, the first surface 7a (second surface 7b) is formed on the molding surface. If so, the mechanical strength of the glass can be brought close to the original strength, thereby preventing the glass film from being broken as much as possible. Specifically, a first insulating film having a first surface 7a (second surface 7b) which is unpolished and has excellent surface accuracy by molding a glass film by a redraw method or an overflow downdraw method which will be described later. 7 can be obtained.

As a means for forming the first insulating film 7, for example, a redraw method can be adopted. According to this method, the thickness dimension t1 of the first insulating film 7 can be easily reduced. Further, the surface quality of the first insulating film 7 can be improved. Furthermore, each side end surface 7c, 7d (refer FIG. 3) of the 1st insulating film 7 is made into a shaping | molding surface (it may call a fire-making surface), and the 1st insulating film 7 has each side end surface 7c, 7d has the advantage that it is difficult to break. The redraw method is a method in which a molded glass is heated again to a temperature near the softening point and stretched to form the glass into a predetermined shape (in the case of this embodiment, a long film). Say.

Of course, as a means for forming the first insulating film 7, glass film forming means other than redraw, such as an overflow down draw method or a slot down draw method, may be employed. The overflow down-draw method is a forming method called fusion method, in which molten glass overflows from both sides of the heat-resistant bowl-like structure, and the overflowing molten glass is joined at the lower end of the bowl-like structure. However, this is a method of obtaining glass having a predetermined shape (long glass film in the case of the present embodiment) by stretching downward. Surface quality can also be improved by forming a glass film by the overflow downdraw method.

When the second insulating film 8 is a glass film, it is possible to make at least one of the glass composition, physical properties, shape, surface properties, dimensions, molding conditions, and the like of the first insulating film 7 described above the same. . Of course, if there is no particular problem in terms of cost and productivity, glass films having different glass compositions, physical properties, shapes, surface properties, dimensions, molding conditions, and the like may be used for the second insulating film 8. .

As mentioned above, although the material (glass composition) of both the insulating films 7 and 8 was described, as long as it can wind up without generating a crack, not only the glass composition mentioned above but various materials are also employable. It is. Specific examples include alkali-free glass, soda glass, and alkali-containing glass.

The thickness dimension t2 of the second insulating film 8 is arbitrary. For example, when the second insulating film 8 is a glass film, the second insulating film 8 has a thickness dimension t1 with respect to the thickness dimension t1 of the first insulating film 7. The thickness dimension t2 is set so that the relative thickness dimension (the value obtained by dividing the thickness dimension t2 of the second insulating film 8 by the thickness dimension t1 of the first insulating film 7) is, for example, 0.3 or more, preferably 0. The thickness dimension t2 is suitably set in the order of 0.6 or more, 0.7 or more, 0.8 or more, more preferably 0.5 or more, more preferably 0.5 or more, and particularly preferably The thickness dimension t2 is set so as to be 0.9 or more. On the other hand, from the viewpoint of the upper limit value, the thickness dimension t2 of the second insulating film 8 is set so that the ratio of the thickness dimensions t1 and t2 is, for example, 3.0 or less, preferably 2.5 or less. More preferably, the thickness dimension t2 is suitably set in the order of 1.8 or less, 1.5 or less, 1.3 or less, 1.2 or less, 1.1 or less, more preferably 2.0 or less. Particularly preferably, the thickness dimension t2 is set to be 1.05 or less.

At the center of the wound body 2, there is a through hole 10 that penetrates the wound body 2 in the direction along the width direction of the wound body 2, that is, in the direction along the center line X <b> 1 of the wound body 2 in FIG. 2. Is provided. In the present embodiment, the through hole 10 penetrates not only the wound body 2 but also the electrodes 3 and 4 attached to both sides in the width direction. Therefore, as shown in FIG. 1, the through hole 10 penetrates the wound film capacitor 1 in the direction along the center line at the center of the wound film capacitor 1. In this case, the center line of the wound film capacitor 1 is equal to the center line X1 of the wound body 2 (see FIGS. 1 and 2). Moreover, in this embodiment, since the internal peripheral surface of the through-hole 10 is comprised by the 2nd surface 8b of the 2nd insulating film 8 (refer FIG. 3), the internal diameter dimension D of the through-hole 10 in this case Is substantially equal to the minimum winding diameter of the insulating film 8 described above.

Next, an example of a method for manufacturing the wound film capacitor 1 having the above-described configuration will be described mainly based on FIGS.

The method for manufacturing the wound film capacitor 1 includes a step S1 for forming the laminated body 9, a step S2 for forming the wound body 2, a step S3 for forming the through hole 10 in the wound body 2, and a winding. And a step S4 of providing positive and negative electrodes 3 and 4 on both sides of the body 2 in the width direction.

(S1) Laminate Forming Step In this step, the long laminate 9 is formed by alternately stacking the two insulating films 7 and 8 and the two conductive layers 5 and 6. In the present embodiment, as shown in FIG. 4, a first insulation in which metal films as first and second conductive layers 5 and 6 are integrally formed on the first and second surfaces 7a and 7b, respectively. The film 7 is placed on the second insulating film 8, and the first conductive layer 5, the first insulating film 7, the second conductive layer 6, and the second insulating film 8 are laminated in this order. A laminated body is formed (see FIG. 5). In FIG. 4, the longitudinal dimension L1 of the first insulating film 7 and the longitudinal dimension L2 of the second insulating film 8 are the same length. The lengths L1 and L2 can be appropriately adjusted by, for example, direct adhesion between the insulating films 8).

At this time, the second surface 7b of the first insulating film 7 and the third surface 8a of the second insulating film 8 or the fourth surface 8b of the second insulating film 7 and the first insulating film Insulating films 7 and 8 are both glass films, and the surface roughness is set to a predetermined size so that the first surface 7 is in direct contact with no adhesive or the like. It is also possible to take a form in which the end in the longitudinal direction of the insulating film 7 protrudes from the conductive layers 5 and 6 in the longitudinal direction (see FIG. 4). Here, when the surface roughness is expressed by the arithmetic average roughness Ra, the arithmetic average roughness Ra of the second surface 7b and the third surface 8a (the first surface 7a and the fourth surface 8b) that are in close contact with each other. Are preferably set to 2.0 nm or less. By setting the arithmetic average roughness Ra of each surface 7b, 8a (7a, 8b) within the above-described range, the two insulating films 7, 8 are wound in a roll shape while being fixed to each other without positional displacement. It is possible to maintain the formed shape (maintain the shape of the wound body 2). Of course, from the viewpoint of improving adhesion, it is preferably 1.0 nm or less, more preferably 0.8 nm or less, 0.4 nm or less, and 0.3 nm or less in order, and 0.2 nm or less. Particularly preferred.

(S2) Winding body formation process At this process, the winding body 2 is formed by winding the laminated body 9 formed by process S1 around the core 11. FIG. Here, although arbitrary forms and materials can be adopted as the core 11, in the present embodiment, as shown in FIGS. 6 and 7, the core 11 having a divided structure is used. The core 11 includes a plurality of divided bodies 12 to 15 each provided with winding surfaces 12a to 15a of the laminated body 9 on the outer periphery, and connecting members 16 and 17 that connect the plurality of divided bodies 12 to 15 to each other. Have In the illustrated example, the four divided bodies 12 to 15 are connected to each other by the two connecting members 16 and 17. Each of the divided bodies 12 to 15 is formed with groove-like fitted portions 12b to 15b into which the connecting members 16 and 17 are fitted (see FIG. 7). By fitting the annular connecting members 16 and 17 to 15b, the four divided bodies 12 to 15 can be connected to each other. If the connection members 16 and 17 and the divided bodies 12 to 15 are to be connected more firmly, screw holes 12c to 15c are provided in the divided bodies 12 to 15 as shown in FIG. , 17 may be provided with screw insertion holes 16a, 17a so as to be connected by screws 18.

In addition, as shown in FIG. 6, between the divided bodies 12 to 15 adjacent in the circumferential direction, the divided bodies 12 to 15 are connected to each other by connecting members 16 and 17 in a predetermined circumferential direction. A gap 19 is formed. The circumferential clearance 19 functions effectively when only a part of the divided bodies 12 to 15 is first removed from the wound body 2 in the formation step S3 of the through hole 10 described later. Details will be described later. Further, a shaft fitting hole 11a into which a rotating shaft (not shown) having a predetermined outer diameter can be fitted is formed at the center of the core 11.

The winding of the laminate 9 using the core 11 having the above configuration is performed as follows, for example. First, as shown in FIG. 8, one end portion 9a in the longitudinal direction of the laminate 9 serving as the end portion on the winding start side is brought into close contact with the outer peripheral surface (winding surfaces 12a to 15a) of the core 11, and the shaft 11 is fitted into the shaft. A rotary drive shaft (not shown) such as a motor is fitted in the hole 11a, and the rotary drive shaft is rotationally driven to start winding the laminated body 9. At this time, as shown in FIG. 8, the second surface 7 b of the first insulating film 7 and the third surface 8 a of the second insulating film 8 are directly connected to each other at one longitudinal end 9 a of the laminate 9. After forming the contact | adhered area | region, it winds up so that the two insulating films 7 and 8 and the two conductive layers 5 and 6 may overlap | superpose in the order shown in FIG. In addition, in order to maintain more reliably the form at the time of winding of the insulating films 7 and 8 after removing the core 11, the 1st surface 7a used as the outer surface of the 1st insulating film 7, and 2nd Projection dimension of the first insulating film 7 from the conductive layers 5 and 6 toward the one end portion 9a in the longitudinal direction so that the fourth surface 8b which is the inner surface of the insulating film 8 is in direct contact with the fourth surface 8b. It is also possible to set p1 (see FIG. 4). That is, both the insulating films 7 and 8 are wound around the core 11 one or more times in a state where the second surface 7b of the first insulating film 7 and the third surface 8a of the second insulating film 8 are in direct contact with each other. It is also possible to set the protruding dimension p1 of the first insulating film 7 from the conductive layers 5 and 6 to such an extent that it can be taken.

Further, as described above, when the two insulating films 7 and 8 are wound in a state of being overlapped with each other, conditions such as a winding speed, a winding angle, and a winding direction of each insulating film 7 and 8 are set. It should be managed appropriately. By appropriately managing the winding condition in this manner, sliding contact between the insulating films 7 and 8 and undue stress concentration can be avoided, and the breakage probability of the glass film can be reduced.

In this way, the laminate 9 is wound around the core 11, and as shown in FIG. 9, for example, the other end 9b in the longitudinal direction, which is the end portion on the winding end side of the laminate 9, is positioned immediately inside thereof. By fixing to the outer surface (third surface 8a) of the second insulating film 8 to be formed, the wound body 2 (see FIG. 10) integrally having the core 11 is formed. At this time, the fixing means of the first insulating film 7 is arbitrary, but it is also possible to employ a fixing means using direct contact with the second insulating film 8 as in the case of starting winding. That is, as shown in FIG. 9, at the other end 9 b in the longitudinal direction of the laminated body 9, the inner surface of the first insulating film 7 (second surface 7 b) and the outer surface of the second insulating film 8. From the conductive layers 5 and 6 of the first insulating film 7 such that both the insulating films 7 and 8 can be wound around the core 11 one or more times in a state in which the surface (the third surface 8a) is in direct contact. It is also possible to set the protrusion dimension p2 (see FIG. 4). By doing in this way, the inner surface (second surface 7b) of the first insulating film 7 located on the outermost radial direction and the outer surface (third surface 8a) of the second insulating film 8 Not only directly but also the inner surface (fourth surface 8b) of the second insulating film 8 and the outer surface (first surface 7a) of the first insulating film 7 in the previous circumference. And are in direct contact. Thereby, it is possible to form the wound body 2 formed by winding the laminated body 9 and firmly fix both the insulating films 7 and 8 at the end of the laminated body 9 on the winding end side.

(S3) Through-hole forming step In this step, the core 11 is removed from the wound body 2 to form a through-hole 10 that penetrates the wound body 2 in the width direction at the center of the wound body 2. Specifically, as shown in FIG. 11, after the screws 18 are loosened and the connecting members 16 and 17 disposed on both sides in the width direction of the core 11 are removed from the divided bodies 12 to 15, the connecting member 16 , 17 are removed from each of the divided bodies 12-15. Thereafter, some of the divided bodies (here, the two divided bodies 12 and 13 having relatively small circumferential dimensions) are moved in the width direction of the wound body 2, so that the partial divided bodies 12, 13 is removed from the wound body 2. In this embodiment, in the state where the divided bodies 12 to 15 are connected to each other by the connecting members 16 and 17, the circumferential gap 19 is provided between the divided bodies 12 to 15, so that a special resistance is provided. It is possible to easily pull out some of the divided bodies 12 and 13. Finally, by removing the remaining divided bodies 14 and 15 from the wound body 2, the wound body 2 is formed, and at the center of the wound body 2, the penetrating through the wound body 2 in the width direction is formed. A hole 10 is formed (see FIG. 2). In the wound body 2 formed at this time, although not shown, the first and second conductive layers 5 and 6 and the first and second insulating films 7 and 8 are both spiral. The first conductive layer 5, the first insulating film 7, the second conductive layer 6, and the second insulating film 8 are repeatedly positioned in this order from the outside in the radial direction.

(S4) Electrode formation process After forming the wound body 2 in this way, both positive and negative electrodes 3 and 4 are formed on both sides of the wound body 2 in the width direction. At this time, the first electrode 3 located on one side in the width direction of the wound body 2 is in contact with the first side end face 5a of the first conductive layer 5 as shown in FIG. The conductive layer 6 is formed so as not to contact the third side end surface 6a. The second electrode 4 located on the other side in the width direction of the wound body 2 is in contact with the fourth side end face 6 b of the second conductive layer 6 and the second side end face of the first conductive layer 5. It is formed so as not to contact 5b. As a result, both the positive and negative electrodes 3 and 4 are formed so as to cover the end in the width direction of the wound body 2 and are electrically connected only to the corresponding conductive layers 5 and 6, as shown in FIG. The wound film capacitor 1 is completed.

In addition, although the formation means of the electrodes 3 and 4 is arbitrary, from a viewpoint which implement | achieves the electrical connection mentioned above easily, the electrically conductive paste containing the metal powder mentioned above is apply | coated to the width direction both sides of the wound body 2 However, it is preferable to form by solidifying. That is, it is difficult to accurately align the positions of the side end faces 7c, 7d, 8c, and 8d (see FIG. 3) in the width direction because of the property of winding the two insulating films 7 and 8 in a spiral shape. Variations in position are unavoidable. Therefore, for example, when the electrodes 3 and 4 are plate-shaped, it is extremely difficult to make them contact with the entire area of the side end faces 5a, 5b, 6a and 6b of the conductive layers 5 and 6. On the other hand, in the case of a paste-like conductive material, it adheres following the position of each side end face 5a, 5b, 6a, 6b. The electrodes 3 and 4 are in close contact with each other. Moreover, when it becomes a low-viscosity liquid when supplied, such as solder, it may flow between the insulating films 7 and 8 and adhere to the conductive layer 5 (6) on the side to be insulated. On the other hand, if it is a paste-like conductive material, the situation of flowing between the insulating films 7 and 8 can be avoided, so that it is necessary to avoid adhesion to the conductive layer 5 (6) on the side to be insulated. It is possible to obtain electrical connection only with the conductive layer 6 (5) on the side.

As described above, in the wound film capacitor 1 according to the present invention, the first and second insulating films 7 and 8 and the first and second conductive layers 5 and 6 are the first conductive layer 5, The first insulating film 7, the second conductive layer 6, and the second insulating film 8 are provided with a wound body 2 that is wound in a roll shape in an overlapping state, and the two insulating films 7, Of these, at least the first insulating film 7 is made of a glass film. Since glass is unlikely to generate oxygen vacancies, the temperature dependence of the dielectric constant can be reduced without reducing the dielectric constant. Therefore, by forming the wound film capacitor 1 with the wound body 2 in the form of winding the first insulating film 7 as a glass film together with the two conductive layers 5 and 6, the capacitor 1 While increasing the capacitance per unit volume, it is possible to effectively prevent a situation in which the circuit does not operate properly due to a temperature change. Therefore, the wound film capacitor 1 capable of storing a large amount of energy can be manufactured in a relatively small size.

Further, the wound film capacitor 1 according to the present invention is provided with a through hole 10 that penetrates the wound body 2 in the width direction at the center of the wound body 2 constituting the capacitor 1. By providing the through hole 10 in this manner, a hollow space, that is, air as an insulator is present in the center of the wound film capacitor 1 over the entire width direction. Therefore, the increase in inductance as described above can be suppressed, and an increase in impedance in the high frequency range can be avoided as much as possible. Of course, if the center of the wound body 2 is a hollow space, the wound film capacitor 1 can be reduced in weight by that amount, which is also suitable for general use of the capacitor.

In the present embodiment, the first and second conductive layers 5 and 6 are both metal films, and the first and second metal films have opposite directions in the thickness direction of the first insulating film 7. A film was formed on each of the first and second surfaces 7a and 7b that are directed to each other (see FIGS. 2 and 4). By integrating the conductive layers 5 and 6 with the first insulating film 7 in this way, the adhesion between the first insulating film 7 and the conductive layers 5 and 6 is enhanced, so both positive and negative conductors (both The distance between the conductive layers 5 and 6) can be reduced, and the capacitance can be further improved. In addition, when the conductive layers 5 and 6 are formed into a film shape, the thickness dimension can be set without considering the handleability of the conductive layers 5 and 6 alone. It is possible to further reduce the size by reducing the size. In addition, by integrating the two conductive layers 5 and 6 with the first insulating film 7 by film formation, the film formation region can be accurately set by masking or the like. Therefore, at the time of winding, it is possible to easily manage the contact mode between the electrodes 3 and 4 and the conductive layers 5 and 6 only by controlling the positions of the side end faces 7c and 7d of the first insulating film 7. it can.

Moreover, in this embodiment, in the longitudinal direction other end part 9b of the laminated body 9 used as the winding end side edge part of the two insulating films 7 and 8 which comprise the wound body 2, the 1st insulating film 7 of The second surface 7b and the third surface 8a of the second insulating film 8 are in direct contact with each other, and one end in the longitudinal direction of the laminate 9 that is the winding start side end of the two insulating films 7 and 8 In 9a, the second surface 7b of the first insulating film 7 and the third surface 8a of the second insulating film 8 were in direct contact with each other. In this way, by taking the form in which the two insulating films 7 and 8 are brought into close contact with each other, the winding body 2 (in the middle of winding the two insulating films 7 and 8 in a roll shape) The shape of the part) or the shape of the wound body 2 after being wound up can be properly maintained. In addition, since it is not necessary to separately prepare a member for fixing the two insulating films 7 and 8, the wound body 2 can be simply configured and can be downsized.

Further, as described above, the two insulating films 7 and 8 are both made of glass film and fixed to each other by direct adhesion, whereby the wound body 2 and thus the wound film capacitor 1 provided with the wound body 2 are used. Can be composed only of non-flammable or flame-retardant inorganic substances. This capacitor is particularly excellent in terms of safety because it has excellent heat resistance and no danger of leakage or burning. In addition, it does not easily deteriorate over time and is excellent in terms of long-term reliability.

As mentioned above, although 1st embodiment of this invention was described, the winding type film capacitor 1 which concerns on this invention, or its manufacturing method is not limited to the said embodiment, Various forms are within the scope of this invention. It is possible to take

For example, in the above embodiment, the first and second conductive layers 5 and 6 are both metal films, and both the first and second metal films (conductive layers 5 and 6) are both of the first insulating film 7. Although the case where it formed into a film on the 1st and 2nd surface 7a and 7b, respectively was illustrated, of course, it is also possible to take forms other than this. FIG. 12 is a perspective view of the wound body 2 according to an example (second embodiment of the present invention), and the first and second conductive layers 5 and 6 and the first and second insulating films 7, A state where 8 is virtually expanded is indicated by a two-dot chain line. As shown in this figure, in the wound body 2 according to this embodiment, the first and second conductive layers 5 and 6 are both metal films, and the first metal film (first conductive layer 5) is The first insulating film 7 is formed on the first surface (here, the outer surface) 7 a, and the second metal film (second conductive layer 6) is formed on the third insulating film 8. A film is formed on the surface (here, the outer surface) 8a. In this case, for example, as shown in FIG. 12, the first conductive layer 5, the first insulating film 7, the second conductive layer 6, and the second insulating film 8 in this order from the outside in the radial direction of the wound body 2. It is possible to take the form which wound two insulating films 7 and 8 in roll shape so that it may be arrange | positioned. Further, from the viewpoint of increasing the degree of freedom at the end of winding, as shown in FIG. 13, the first insulating film 7, the first conductive layer 5, the second insulating film 8, from the radially outer side of the wound body 2, It is also possible to take a form in which two insulating films 7 and 8 are wound into a roll shape so as to be arranged in the order of the second conductive layer 6. Of course, in this case, as shown in FIG. 3, the first conductive layer 5 and the second conductive layer 6 may be offset from each other in different directions in the width direction. Or although illustration is abbreviate | omitted, both the 1st and 2nd conductive layers 5 and 6 are made into a metal film, these 1st and 2nd metal films and the 1st and 2nd insulating films 7 and 8 are made into 1st. One metal film, the first insulating film 7, the second metal film, and the second insulating film 8 may be overlapped in this order and wound into a roll shape.

Moreover, regarding the wound body forming step S2, for example, as shown in FIG. 14, the first insulating film 7 and the second insulating film 8 that are wound in a roll shape are drawn out so as to overlap each other, The wound body 2 may be formed by winding around the core 11 (third embodiment of the present invention). In this case, the formation process S1 of the laminated body 9 and the formation process S2 of the wound body 2 are performed simultaneously. In this embodiment, the case where the winding starts from the second insulating film 8 and the winding ends with the second insulating film 8 will be described below as an example.

Specifically, first, as shown in FIG. 15, the longitudinal direction one end 8 e of the second insulating film 8 serving as the winding start side end is brought into close contact with the outer peripheral surface of the core 11, and the core 11 is already described. In this way, the second insulating film 8 starts to be wound. Then, when the second insulating film 8 is wound, for example, about 0.5 turn (1/2 turn) to about 3 turns (2 turns in FIG. 15), the first insulating film 7 is turned into the second insulating film. 8 is brought into close contact with the outer surface (third surface 8a), and the winding of the second insulating film 8 is continued. Thereby, in a state where the first insulating film 7 and the second insulating film 8 overlap each other, both the insulating films 7 and 8, in other words, the laminate 9 is wound around the core 11. Further, by starting winding of the second insulating film 8 in advance of the first insulating film 7, the outer surface of the second insulating film 8 (third surface 8a) and a radius corresponding to one circumference thereof It will be in the state which the inner surface (4th surface 8b) of the 2nd insulating film 8 located in the direction outer side was closely_contact | adhered directly. Thereby, since it will be in the state where 2nd insulating films 8 were firmly fixed in the winding start side of the 2nd insulating film 8, even after removing the core 11, at the time of winding-up of the insulating films 7 and 8 It becomes possible to reliably maintain the form. In addition, naturally the amount of preceding winding of the 2nd insulating film 8 is not restricted to the said illustration, For example, 0.1 rounds, 0.25 rounds, 1 round, 1.5 rounds, 5 rounds, etc. arbitrary The amount of winding can be set.

When the first insulating film 7 is introduced around the core 11, for example, as shown in FIG. 14, the roll body is arranged so that the first insulating film 7 is introduced inside the second insulating film 8 in the radial direction. Winding may be performed by arranging 20, 21. Thus, by arranging both the insulating films 7 and 8 (roll bodies 20 and 21) and starting the winding operation, the longitudinal direction one end portion 7e that becomes the winding start side end portion of the first insulating film 7 is obtained. Is sandwiched between the second insulating films 8 and the both insulating films 7 and 8 can be wound up while being wound (see FIG. 15). Therefore, the winding start state of the first insulating film 7 is stabilized, and as a result, the wound body 2 having excellent shape accuracy can be formed.

In this way, by winding both the insulating films 7 and 8 (that is, the laminated body 9) around the core 11, the wound body 2 having the core 11 integrally is formed as in FIG. At this time, for example, similarly to the start of winding, after the first insulating film 7 is wound, the second insulating film 8 is continuously wound, for example, about 0.5 turn (1/2 turn) to 3 turns (2 in FIG. 16). The outer surface (third surface 8a) of the second insulating film 8 and the inner surface (fourth surface) of the second insulating film 8 positioned radially outward by the circumference of the second insulating film 8 by winding. 8b) are fixed to each other by direct contact. Thereby, the winding body 2 of the state by which the winding form of both the insulating films 7 and 8 was maintained reliably can be obtained. In addition, since the end portion on the winding end side of the first insulating film 7 integrally formed with the first and second conductive layers 5 and 6 is completely covered by the second insulating film 8, The degree of freedom on the winding end side of the body 2 is increased. Note that the additional winding amount on the winding end side of the second insulating film 8 is not limited to the above-described example, and for example, 0.1 turn, 0.25 turn, 1 turn, 1.5 turn, An arbitrary winding amount such as 5 laps can be used.

In this embodiment, the roll body 20 of the first insulating film 7 and the roll body 21 of the second insulating film 8 are arranged on the same side (both left sides in FIG. 14) with respect to the core 11. Of course, the roll body 20 of the first insulating film 7 and the roll body 21 of the second insulating film 8 are arranged on different sides with respect to the core 11 (FIG. 14). In other words, the roll body 20 may be provided on one of the left and right sides of the core 11 and the roll body 21 may be provided on the other side, and the core 11 may be drawn out. Further, with respect to the drawing position around the core 11, it is not always necessary to pull out the both insulating films 7 and 8 at the same circumferential position. For example, although not shown, each is directed toward a position shifted by 180 ° in the circumferential direction. The insulating films 7 and 8 may be pulled out.

Moreover, in the above description, the winding body 2 of the winding type film capacitor 1 is exemplified as one in which the two insulating films 7 and 8 are wound in a true cylindrical shape (see FIG. 9 and the like). Of course, other shapes may be used. For example, as shown in FIGS. 17 and 18, when viewed from the direction along the center line, the wound body 22 (fourth embodiment of the present invention) having an elliptical shape or a flat shape including a straight portion is formed. As long as the two insulating films 7 and 8 are wound into a roll shape such as the wound body 23 (fifth embodiment of the present invention), various forms can be taken.

Hereinafter, the function and effect of the present invention will be described based on examples.

<Production of glass plate>
First, after preparing nine kinds of glass raw materials (samples No. 1 to No. 9) so as to have the glass composition described in Table 1, the obtained glass batch was supplied to a glass melting furnace and 1500 to It melted at 1600 ° C. Next, the obtained molten glass was poured onto a carbon plate, formed into a flat plate shape, and then slowly cooled over 10 hours from the strain point to room temperature. Finally, the obtained glass plate is processed, and various properties shown below (density, strain point, annealing point, softening point, high temperature viscosity, thermal expansion coefficient, liquidus temperature, liquidus viscosity, ratio Dielectric constant) was evaluated. The results are shown in Table 1.

The density was measured by the well-known Archimedes method.

The strain point and annealing point were measured by a method based on ASTM C336-71.

The softening point was measured by a method based on ASTM C338-93.

The high temperature ^{viscosity, 10 4.0 dPa · s, 10} 3.0 dPa · s, and the temperature at 10 ^2.5 dPa · s, was measured by a platinum ball pulling method.

The thermal expansion coefficient was measured with a dilatometer in the range of 30 to 380 ° C.

As for the liquidus temperature, the glass powder that passes through a standard sieve 30 mesh (about 500 μm) and remains in 50 mesh (about 300 μm) is placed in a platinum board and held in a temperature gradient furnace for 24 hours, and the temperature at which crystals precipitate. Was measured.

Regarding the liquid phase viscosity, the viscosity of the glass at the liquid phase temperature was measured by a platinum ball pulling method.

The relative dielectric constant was measured by a method based on ASTM D150.

<Production of capacitor>
Sample No. above. 1-No. After heating the glass plate according to 9 to near the softening point, the glass plate was stretch-molded by a redraw method, and a glass film (hereinafter referred to as a base glass film) having a longitudinal dimension of 50 m, a width dimension of 25 mm, and a thickness dimension of 10 μm. A glass film (hereinafter referred to as an intervening glass film) having a longitudinal dimension of 50 m, a width dimension of 25 mm, and a thickness dimension of 9 μm was obtained. The material is the same for any glass film. The arithmetic average roughness Ra was both set to 0.2 nm.

Next, with respect to one surface and the other surface (the first surface 7a and the second surface 7b of the first insulating film 7 referred to in the present invention) of the obtained base glass film, the thickness dimension is 45 nm. A Cu film was formed by film formation. During film formation, a region from the second side end face (see FIG. 3 and paragraph 0056) to 3 mm of one surface was masked so that a Cu film was not formed on the masking portion. In addition, a region from the first side end surface (see FIG. 3 and paragraph 0056) to 3 mm of the other surface was masked so that no Cu film was formed on the masking portion. In this way, after the Cu film was formed, the masking portion was removed.

Subsequently, the substrate glass film and the interposed glass film were overlapped, and the overlapped body was wound around the outer peripheral surface of the core having an outer diameter of 50 mm shown in FIG. 6 to form a wound body. Thereafter, the core was removed from the wound body by the method described in paragraph 0104, for example. Moreover, the through-hole was formed in the center of a wound body by removing a core from a wound body.

After removing the core in this manner, an electrode layer was formed by applying and solidifying a conductive paste on both sides of the wound body in the width direction. Specifically, the entire first side end face of the Cu film formed on one surface of the base glass film is electrically connected, and the first side end face of the Cu film formed on the other surface The entire region was not in contact with the electrode layer (not electrically connected). Further, the entire second side end face of the Cu film formed on the other surface of the base glass film is electrically connected, and the entire second side end face of the Cu film formed on one surface is an electrode. The layer was not in contact (not electrically connected). Here, CW2400 manufactured by ITW Chemtronics was used as the conductive paste. As described above, sample No. 1-No. A wound film capacitor according to 9 was produced.

Sample No. The impedance of the wound film capacitor according to 1 was measured with an impedance analyzer (Solartron 1260 type, measurement conditions: frequency 1 Hz to 32 MHz, applied voltage 100 mV). The measurement results are shown in FIG. The capacitance was calculated from the impedance at 1 Hz and found to be 7.8 μF.

Claims (18)

1. The first and second conductive layers and the first and second insulating films are in the order of the first conductive layer, the first insulating film, the second conductive layer, and the second insulating film. A wound film capacitor including a wound body that is wound into a roll shape in an overlapping state,
   The wound film capacitor in which the at least first insulating film is a glass film, and a through-hole penetrating the wound body in the width direction is provided at the center of the wound body.
2. 2. The wound film capacitor according to claim 1, wherein the second insulating film is a glass film.
3. The first and second conductive layers are both metal films, and the first and second metal films have a first surface and a second surface oriented in opposite directions in the thickness direction of the first insulating film. The wound film capacitor according to claim 1, wherein the wound film capacitor is formed on each surface.
4. The first and second conductive layers are both metal films, and the first metal film is formed on a first surface directed in one thickness direction of the first insulating film, and the second The wound film capacitor according to claim 1 or 2, wherein a metal film is formed on a third surface oriented in one thickness direction of the second insulating film.
5. The first conductive layer has a first side end face that faces one side in the width direction and a second side end face that faces the other side in the width direction,
   The second conductive layer has a third side end face that faces one side in the width direction, and a fourth side end face that faces the other side in the width direction,
   The second side end surface of the first conductive layer is offset to one side in the width direction with respect to the fourth side end surface of the second conductive layer, and the second conductive layer The wound film capacitor according to any one of claims 1 to 4, wherein the third side end face is offset to the other side in the width direction with respect to the first side end face of the first conductive layer. .
6. A first electrode in contact with the first conductive layer and separated from the second conductive layer is provided on one side in the width direction of the wound body,
   The second electrode that is in contact with the second conductive layer and is separated from the first conductive layer is provided on the other side in the width direction of the wound body. Winding film capacitor.
7. The wound film capacitor according to any one of claims 1 to 6, wherein the surfaces of the glass film are in direct contact with each other at the end in the longitudinal direction on the winding end side of the glass film.
8. The wound film capacitor according to any one of claims 1 to 7, wherein surfaces of the glass film are in direct contact with each other at an end in a longitudinal direction on a winding start side of the glass film.
9. 9. The wound film capacitor according to claim 1, wherein the thickness of the first insulating film is set to 50 μm or less.
10. The wound film capacitor according to any one of claims 1 to 9, wherein a minimum winding diameter of the wound body is set to 100 mm or less.
11. The wound film capacitor according to any one of claims 1 to 10, wherein a dimension in a longitudinal direction of the first insulating film is set to 0.05 m or more.
12. 12. The wound film capacitor according to claim 1, wherein a value obtained by dividing a width direction dimension of the first insulating film by a thickness dimension of the first insulating film is set to 1000 or more.
13. The wound film capacitor according to any one of claims 1 to 12, wherein a relative dielectric constant of the glass film as the first insulating film is set to 5.0 or more.
14. The arithmetic average roughness Ra of the first surface oriented in one thickness direction of the first insulating film or the second surface oriented in the other thickness direction is set to 5 nm or less. The wound film capacitor according to claim 1.
15. The first insulating film is, by mass%, SiO ₂ : 20 to 70%, Al ₂ O ₃ : 0 to 20%, B ₂ O ₃ : 0 to 17%, MgO: 0 to 10%, CaO: 0 The wound film capacitor according to any one of claims 1 to 14, which has a glass composition containing -15%, SrO: 0-15%, BaO: 0-40%.
16. The first and second conductive layers, and the first and second insulating films in which at least the first insulating film is a glass film, the first conductive layer, the first insulating film, the second Forming a laminate of the insulating film by overlapping the conductive layer and the second insulating film in this order;
    Winding the laminate around a core to form a wound body;
    And a step of forming a through-hole penetrating the wound body in the width direction at the center of the wound body by removing the core from the wound body. .
17. As said 1st insulating film, the 1st and 2nd metal film as said 1st and 2nd electroconductive layer was each formed into a film on the 1st and 2nd surface which faces the direction which opposes the thickness direction After preparing things,
    The wound film capacitor according to claim 16, wherein the laminated body is formed by overlapping the first insulating film on which the first and second metal films are formed and the second insulating film. Manufacturing method.
18. As the core, a plurality of divided bodies each having a winding surface of the laminate on the outer periphery, and a connection member that connects the plurality of divided bodies are prepared.
    After winding the laminated body around the core in a state where the plurality of divided bodies are connected with the connecting member to form the wound body,
    A part of the plurality of divided bodies is removed from the wound body after removing the connection member and the connection state between the plurality of divided bodies is eliminated, and then the remaining portions of the plurality of divided bodies are removed. A method for producing a wound film capacitor according to 16 or 17.

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