JP2012069633A - Metalized film capacitor or manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the shortcoming in a metalized film capacitor comprised of a single or plural capacitor elements composed of metalized film wound in cylindrical form and provided with a metallicon electrode at both ends, a bottomed cylindrical case with an opening at the top end face for accommodating the capacitor elements, a pair of external terminals disposed from the outer surface through the inner surface of this sealed body, and an extraction tab interconnecting the external terminals and the metallicon electrodes, that even when a space between the case and the capacitor element is narrow, there occurs a portion which is not filled with an insulating resin, to ensure that humidity resistance, vibration resistance, etc. can be maintained stably over a long period even when used over a wide temperature range.SOLUTION: The winding core of a capacitor element is hollow in the inside and has the same winding core shaft direction as the shaft direction of the case. The winding core shaft of the capacitor element includes a resin injection tool which injects a resin from an open hole provided in the sealed body penetrating from the outer surface through the inner surface thereof, with the insulating resin discharged from the internal bottom part of the case after passing the winding core shaft of the capacitor element.

Description

  The present invention relates to a metallized film capacitor in which one or a plurality of capacitor elements using a metallized film are housed in a case having an opening, or a method for manufacturing the same.

  In recent years, an inverter circuit suitable for energy saving and high efficiency has been adopted from the consideration of the environment. However, since the working voltage is high, there is a tendency to use a film capacitor among the capacitors. In particular, in applications such as on-vehicle moving bodies, conditions for use such as moisture resistance and vibration resistance are required over a long period of time in a wide temperature range.

  Conventionally, as shown in FIG. 6, a capacitor element 2 using a metallized film is housed in a case 4 having an opening at the upper end surface, and a metallized film capacitor filled with an insulating resin 9 is composed of two metallized films. After the metallized electrode 3 is sprayed on the wound end face to draw out the electrode, the metallicon electrode 3 is applied, and then a temperature treatment called heat treatment is performed as necessary to manufacture the capacitor element 2. Next, the external lead terminal 1 was connected to one or a plurality of electrodes at both ends of the capacitor element 2, housed in the resin case 4, and then filled with the insulating resin 9.

  As shown in Patent Document 1, the insulating resin is filled by a method of discharging the insulating resin with a nozzle of a filling machine installed above the opening of the case and filling the gap between the case and the capacitor element with the insulating resin. Has been.

JP 2007-129128 A

  However, if the case and the capacitor element have the same shape as in the case of storing the wound capacitor element in a cylindrical shape in a cylindrical case with an opening on the upper end surface, the case and the capacitor element The gap between and is likely to be narrow, and the insulating resin is difficult to fill.

  The present invention eliminates the problem that an unfilled portion of insulating resin occurs even if the gap between the case and the capacitor element is narrow, and stabilizes moisture resistance and vibration resistance over a long period of time under a wide temperature range of use conditions. It is aimed.

In order to solve the above problems, the present invention provides the following film capacitor and a method for manufacturing the same.
(1) Using a metallized film, winding it into a cylindrical shape, one or a plurality of capacitor elements provided with metallicon electrodes at both ends, and a bottomed cylindrical shape having an opening on the upper end surface that accommodates this capacitor element And a metallized film capacitor having an insulating resin filling the case, wherein the winding core of the capacitor element is cylindrical and the axis of the winding core is in the same direction as the axis of the case. Insulating resin is injected from the opening of the capacitor element, passes through the core axis of the capacitor element, and a metalized film is provided on the core axis part of the capacitor element to discharge the insulating resin from the bottom of the capacitor element Capacitor.
(2) The metallized film capacitor according to (1), wherein the resin injection tool is a tubular member extending from the opening side of the case into the winding core of the capacitor element.
(3) The metallized film capacitor according to (1), wherein the resin injection tool is a connecting member that is connected to the winding core of the capacitor element.
(4) The metallized film capacitor according to (1), wherein the resin injection tool is a dual-purpose member that also serves as a core member of the capacitor element, and connects the cores of the capacitor element.
(5) Using a metallized film, winding it into a cylindrical shape, one or a plurality of capacitor elements provided with metallicon electrodes at both ends, and a bottomed cylindrical shape with an opening on the upper end surface that accommodates this capacitor element And a method of manufacturing a metallized film capacitor having an insulating resin filling the case,
The winding core of the capacitor element is cylindrical, and the axis of the winding core is in the same direction as the axis of the case,
A method of manufacturing a metallized film capacitor, in which an insulating resin is injected from an opening of a case, passes through the core of the capacitor element, and is discharged from the bottom of the capacitor element to fill the case.

  According to the present invention, even when the gap between the case and the capacitor element is narrow, the problem that an unfilled portion of the insulating resin is generated is eliminated, and the moisture resistance and vibration resistance are stabilized over a long period of time under a wide temperature range. A metallized film capacitor can be provided.

1 shows a perspective schematic view of a cross section of a metallized film capacitor according to the present invention. 3 shows a method of injecting an insulating resin of another metallized film capacitor according to the present invention. Figure 3 shows a schematic cross section of another metallized film capacitor according to the present invention. Figure 3 shows a schematic cross section of another metallized film capacitor according to the present invention. Figure 3 shows a perspective schematic view of a cross section of another metallized film capacitor according to the present invention. 1 shows a schematic cross-sectional view of a conventional metalized film capacitor.

The capacitor element of the present invention is obtained by winding a metallized film in which a metal such as aluminum, copper, or zinc is deposited on a film surface such as polyethylene terephthalate or polypropylene, and winding the metal foil and the film on both ends, and zinc and copper on both end faces. In general, a metallicon electrode is provided by spraying a metal such as aluminum.
The production method is to use a winding jig to first roll the film as a winding core, and then roll the metallized film on top of it, and finally remove the winding jig. There is a method in which a winding core such as a cylindrical plastic is inserted, a metallized film is stacked and wound, and then the winding jig is removed while leaving the winding core such as plastic.

  The metallicon electrode of the present invention can be generally used for a film capacitor, and is made of a metal or alloy such as copper, zinc, aluminum, tin, or solder, and is formed on the end face of the capacitor element by thermal spraying. It is. In some cases, the surface of the electrode may be plated.

  The case of the present invention is a bottomed cylindrical container having an opening on the upper end surface and generally usable for a film capacitor, and is made of plastic or metal. In the case of plastic, for example, it is made of a resin such as polyethylene terephthalate, polybutylene terephthalate, polycarbonate, or polyphenylene sulfide. If it is a metal, it will consist of aluminum, magnesium, iron, stainless steel, copper, etc., for example. Some have metal laminated with plastic.

The resin injection tool of the present invention is a tool for injecting insulating resin from the opening of the case, passing through the inside of the core of the capacitor element, and discharging the insulating resin from the bottom of the capacitor element. It is a general term for members and dual-purpose members.
The tubular member is a tubular member extending from the opening of the case into the winding core of the capacitor element. Connected to the nozzle tip of the filling machine provided above the opening of the case, the insulating resin is discharged from the bottom of the capacitor element. In order to obtain insulation in the capacitor element or between the capacitor elements, the tubular member is preferably an insulating material at least on the outer surface. However, if the outer surface is conductive like a metal tube, the capacitor is injected after injecting an insulating resin. Extracted from the core of the element. If it stays in the winding core of the capacitor element, the reinforcing property against vibration of the capacitor element is improved.
The connecting member is a member that connects the winding cores of the capacitor element, and a member that connects the through hole provided in the sealing body and the winding core of the capacitor element when there is a sealing body at the opening of the case, or the case In the case where there is no sealing body in the opening, the member connects the surface of the opening of the case and the winding core of the capacitor element.
The dual-purpose member is a member that is also used as the core member of the capacitor element. To get.

  The insulating resin of the present invention is an insulating material generally used for filling a film capacitor, and is obtained by mixing a filler or the like with a resin such as an epoxy resin or a urethane resin. As the filler, hydroxides such as silicon, titanium, aluminum, calcium, zirconium, and magnesium, oxides, carbides, nitrides, and composites thereof can be used. If necessary, a flame retardant and an antioxidant may be added.

Hereinafter, the present invention will be described based on embodiments shown in the drawings.
FIG. 1 shows a schematic perspective view of a cross section of a metallized film capacitor according to the present invention. 1A shows a case where there is one capacitor element, and FIG. 1B shows a case where there are two capacitor elements. In addition, the insulating resin with which the case is filled is omitted (hereinafter, the insulating resin is also omitted in FIGS. 3, 4 and 5).
Each of the external lead electrodes 1 has one end connected to the metallicon electrode portion 3 of the capacitor element 2 and the other end led out from the opening end portion of the cylindrical case 4.
The capacitor element 2 is accommodated in the case 4 such that the axis of the winding core 5 is in the same direction as the axis of the cylindrical case 4.
The resin injection tool 6 is inserted into the winding core 3 of the capacitor element 2 as a tubular member. In the case of FIG. 1B, the two capacitor elements 2 are inserted in a skewered manner. Insulating resin is introduced by chucking the inlet 6a of the tubular member by the insulating resin supply device, and injected from the outlet 6b of the tubular member. After completion of the injection of the insulating resin, the tubular member of the resin injection tool 6 may be extracted.

FIG. 2 shows a method of injecting an insulating resin of another metallized film capacitor according to the present invention. 2A shows the state before the injection of the insulating resin, FIG. 2B shows the state during the injection of the insulating resin, and FIG. 2C shows the state after the injection of the insulating resin.
First, as shown in FIG. 2A, the resin injection tool 6 includes a through hole 7a for the resin injection tool provided in the sealing body 7 at the opening of the case 4 and the winding core 5 of the capacitor element 2 as a connecting member. It is a member which connects between. Further, the insulating resin supply device 8 is brought to the inlet 6 a side of the resin injection tool 6.
Next, as shown in FIG. 2 (b), the insulating resin supply device 8 chucks the inlet 6 a of the resin injection tool 6, and then passes the insulating resin 9 on the winding core 5 of the capacitor element 2 through the resin injection tool 6. inject.
Next, as shown in FIG. 2C, excess insulating resin 9 after being injected into the capacitor is discharged out of the capacitor through the through hole 7 b for discharging the insulating resin provided in the sealing body 7. Further, the discharged insulating resin 9 is blocked by a dam 7 c provided around the sealing body 7.
The sealing body is not always necessary, and a part of the resin injection tool may be inserted into the winding core of the capacitor element.
As shown in FIG. 3, the connecting member of the resin injection tool 6 may be integrated with the sealing body 7. When the connecting member is a separate part from the sealing body, the degree of freedom of the shape of the capacitor element increases.

FIG. 4 shows a schematic cross section of another metallized film capacitor according to the present invention. The case where there are two capacitor elements 2 is shown, and the resin injection tool 6 connects between the through hole 7a for the resin injection tool provided in the sealing body 7 of the opening of the case 4 and the core 5 of the capacitor element 2. In addition to the member, it is a member for connecting the winding cores 5 of the capacitor element 2 together.
Further, a member that connects the winding cores 5 of the capacitor element 2 may be provided with a leak hole 10 that leaks insulating resin in a gap between the capacitor elements 2. The leak hole 10 can easily fill a gap between the capacitor elements 2.

FIG. 5 shows a schematic perspective view of a cross section of another metallized film capacitor according to the present invention. The case where two or more capacitor elements 2 are provided in series in the winding axis direction is shown, and the resin injection tool 6 is a dual-purpose member that also serves as the core member 5a of the capacitor element 2, and between the cores 5 of the capacitor element 2 The two are linked together.
FIG. 5 (a) shows that the core member 11 as the resin injection tool 6 is mainly located on the capacitor element 2 on the opening side of the case 4 (upper side in FIG. 5) and protrudes from both sides. The case where it inserts in part to the core 5 of the capacitor element 2 on the side is shown.
FIG. 5B shows that the winding core members 11 that are the resin injection tools 6 are both in the capacitor element 2 and are connected at opposite ends.

  DESCRIPTION OF SYMBOLS 1 ... External extraction electrode, 2 ... Capacitor element, 3 ... Metallicon electrode, 4 ... Case, 5 ... Core, 5a ... Core member, 6 ... Resin injection tool, 6a ... Inlet, 6b ... Outlet, 7 ... Sealing body, 7a ... Through hole for resin injection tool, 7b ... Through hole for discharging insulating resin fat, 7c ... Dam, 8 ... Insulating resin supply device, 9 ... Insulating resin, 10 ... Leak hole, 11 ... Winding core member

Claims (5)

  One or a plurality of capacitor elements having metallized electrodes provided at both ends, and a bottomed cylindrical case with an opening on the upper end surface, using a metallized film and wound into a cylindrical shape And a metallized film capacitor having an insulating resin filling the inside of the case, wherein the winding core of the capacitor element is cylindrical, the axis of the winding core is in the same direction as the axis of the case, and the opening of the case A metallized film capacitor in which a resin injection tool for injecting an insulating resin, passing through the core of the capacitor element, and discharging the insulating resin from the bottom of the capacitor element is provided on the core axis of the capacitor element.   2. The metallized film capacitor according to claim 1, wherein the resin injection tool is a tubular member extending from the opening side of the case into the winding core of the capacitor element.   2. The metallized film capacitor according to claim 1, wherein the resin injection tool is a connecting member that is connected to the winding core of the capacitor element.   The metallized film capacitor according to claim 1, wherein the resin injection tool is a dual-purpose member that also serves as a core member of the capacitor element, and connects between the cores of the capacitor element. One or a plurality of capacitor elements having metallized electrodes provided at both ends, and a bottomed cylindrical case with an opening on the upper end surface, using a metallized film and wound into a cylindrical shape In the method of manufacturing a metallized film capacitor having an insulating resin filling the case,
The winding core of the capacitor element is cylindrical, and the axis of the winding core is in the same direction as the axis of the case,
A method of manufacturing a metallized film capacitor, in which an insulating resin is injected from an opening of a case, passes through the core of the capacitor element, and is discharged from the bottom of the capacitor element to fill the case.

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