JP5186939B2 - Case mold type capacitor - Google Patents

Description

  INDUSTRIAL APPLICABILITY The present invention is used in various electronic equipment, electrical equipment, industrial equipment, automobiles, etc., and in particular, a metallized film capacitor that is optimal for smoothing, filtering, and snubbing of a motor drive inverter circuit of a hybrid car is contained in a case. And a resin-molded case mold type capacitor.

  In recent years, from the viewpoint of environmental protection, all electric devices are controlled by inverter circuits, and energy saving and high efficiency are being promoted. In particular, in the automobile industry, hybrid vehicles (hereinafter referred to as HEVs) that run on electric motors and engines have been introduced into the market, and the development of technologies relating to energy saving and high efficiency has been activated, which is friendly to the global environment.

  Since such a HEV electric motor has a high operating voltage range of several hundred volts, a metallized film capacitor having high withstand voltage and low loss electric characteristics as a capacitor used in connection with such an electric motor. In addition, the trend of adopting metalized film capacitors with a very long life is conspicuous due to the demand for maintenance-free in the market.

  And since the metallized film capacitor used for HEVs in this way is required to have a high withstand voltage, large current, large capacity, etc., a plurality of metallized films connected in parallel by bus bars. A case mold type capacitor in which a capacitor is housed in a case and a mold resin is poured into the case has been developed and put into practical use.

  However, in such a case mold type capacitor, in addition to the dimensional variation in the metallized film capacitor itself, the metallized film capacitors come into contact with each other during assembly, or the metallized film capacitor is subjected to heat cycle in the usage environment. There were problems such as swelling and contact.

  In addition, when the AC voltage is applied to such a metallized film capacitor, when the AC voltage is superimposed on the DC voltage, the metallized film capacitor itself vibrates due to the generation of a ripple current, and this vibration causes the metallized film arranged in parallel. There is a problem that film capacitors make contact with each other, and such contact between metallized film capacitors has the problem that in the worst case there is a risk of short-circuiting, thus reducing such vibrations. Various proposals have been made for this purpose.

For example, as a means for reducing the vibration by the capacitor itself, a liquid insulator such as 25 mm ² / s at 25 ° C. is formed on a capacitor element formed by laminating and winding a metallized plastic film having an electrode film on the surface of a dielectric film. And by impregnating methyl hydrogen silicone oil, which is a low-viscosity crosslinking reactive monomer, and then heating to 130 ° C. for 15 minutes or 100 ° C. for 60 minutes to polymerize methyl hydrogen silicone oil to increase the viscosity. There has been proposed a method for manufacturing a capacitor capable of suppressing the vibration of the capacitor that occurs when an alternating voltage is applied (Patent Document 1).

  In addition, as a means for reducing vibration in a metallized film capacitor of a type in which a metallized film capacitor is placed in a resin case and molded with resin, the present applicant shows the following FIGS. 3A and 3B. I have a proposal like this.

  FIGS. 3A and 3B are a front sectional view and a side sectional view showing the structure of a case mold type capacitor in which the above metallized film capacitor is resin-molded, in which 11 is composed of a metallized film. A wound capacitor element, 12 is a resin case, 13 is a connection terminal, 13a is a bus bar for connecting the electrode parts of the capacitor element 11, 14 is a filling resin, and 15 is a sound-absorbing and soundproofing material.

  The conventional metallized film capacitor configured as described above has a configuration in which a sound absorbing and soundproof material 15 made of urethane foam is disposed between the outer surface of the capacitor element 11 and the inner surface of the resin case 12. 11 was able to suppress the propagation of 11 vibrations to the outside, enhance the sound insulation effect, and reduce the noise to the outside (Patent Document 2).

As prior art document information related to the invention of this application, for example, Patent Document 1 and Patent Document 2 are known.
JP 2004-303934 A JP 2005-93515 A

  However, in the above conventional metallized film capacitor, the vibration of the capacitor element is reduced by the capacitor itself (Patent Document 1) or in a resin-molded state placed in a resin case (Patent Document 2). However, there was no vibration. This is because heat treatment is performed on the capacitor element 11 that has been assembled, but a plurality of wound metallized films shrink, but an interlayer gap is easily generated between the metallized films. When a voltage is applied, a ripple current is generated when an AC voltage is superimposed on a DC voltage, and the capacitor element 11 vibrates. When such vibration increases, adjacent capacitor elements come into contact with each other, which is the worst. In this case, there is a possibility of causing a short circuit, and there is a problem that higher vibration suppression is necessary.

  The present invention solves such a conventional problem, and suppresses vibration generated in a metallized film capacitor, and also prevents a short circuit by preventing contact between metallized film capacitors. It is intended to provide.

In order to solve the above problems, the present invention provides a case mold type capacitor in which a plurality of elements each having a pair of electrodes provided on both end faces are connected in parallel with each other by a bus bar, and these are housed in a case and resin molded. The element is formed in an oval cross-section, accommodated in the case with the major axis direction vertical, and a plurality of elements arranged in parallel are filled with mold resin and at least the element In this configuration, a plurality of partition walls having thicker portions disposed in the vicinity of the electrodes are provided so as to rise from the inner bottom surface of the case .

  As described above, the case mold type capacitor according to the present invention has a configuration in which an element formed in an oval cross section is accommodated in a case with the major axis direction being a vertical direction, and a mold resin is filled between the elements. Even if the device generates a ripple current by applying an AC voltage or an AC voltage superimposed on the DC voltage to the device, even if the device itself vibrates, the vibration is suppressed by the mold resin filled between each device. In addition, since the elements are separated from each other by the mold resin while being insulative, there is an effect that they do not come into contact with each other and are not short-circuited.

(Embodiment 1)
Hereinafter, the first and second aspects of the present invention will be described with reference to the first embodiment.

  1A to 1C are a plan sectional view, a front sectional view, and a side sectional view showing a configuration of a case mold type capacitor according to Embodiment 1 of the present invention. In FIG. 1 represents a first metallized film capacitor (hereinafter referred to as a first element 1), and 2 represents a second metallized film capacitor (hereinafter referred to as a second element 2) having an oval cross section. The element 1 (same for the second element 2) is a pair of metallized films (not shown) in which a metal vapor deposition electrode is formed on one or both sides of a dielectric film made of polypropylene, and the metal vapor deposition electrode is a dielectric. The metallicon electrode 1a (metallicon electrode 2a in the second element 2) in which the cross-section is flattened by press working after being wound in a state of being opposed to each other through a film and zinc is sprayed on both end faces. Forming each Those constructed by providing a pair of extraction electrodes of the P and N poles by Rukoto.

  The first element 1 and the second element 2 have different functions. In the present embodiment, the first element 1 is used for smoothing the inverter, and the second element 2 is used for the filter. Although used, the present invention is not limited to this.

  Reference numeral 3 denotes a first P-pole bus bar, 3a denotes a P-pole terminal for external connection provided at one end of the first P-pole bus bar 3, and 3b denotes a plurality of locations so as to branch from the first P-pole bus bar 3. The first P-pole bus bar 3 includes a plurality of the first element 1 with the major axis direction in the vertical direction (three in the present embodiment, but this is not limitative). In parallel with a predetermined gap between each of the first elements 1, the above-mentioned one side of the pair of metallicon electrodes 1 a provided on both end faces of the first element 1 It joins by soldering the junction part 3b.

  Reference numeral 4 denotes a first N pole bus bar which is formed in the same manner as the first P pole bus bar 3 and is joined to the metallicon electrode 1a on the other side of the first element 1. The elements 1 are connected in parallel by the first P-pole bus bar 3 and the first N-pole bus bar 4 in a state where the major axis direction is the vertical direction and a gap is provided between the first elements 1 (hereinafter referred to as this In this way, a state in which the bus bars are connected in parallel is referred to as a first element unit for convenience).

  Reference numeral 5 denotes a second P-pole bus bar, 5a denotes a P-pole terminal for external connection provided at one end of the second P-pole bus bar 5, and 5b denotes a plurality of locations branching from the second P-pole bus bar 5. The second P-pole bus bar 5 has a plurality of the second elements 2 with the major axis direction in the vertical direction (two in the present embodiment, but this is not limitative). In parallel with a predetermined gap between each of the second elements 2, the above-mentioned one side of the pair of metallicon electrodes 2a provided on both end faces of the second element 2 It joins by soldering the junction part 5b.

  Reference numeral 6 denotes a second N-pole bus bar that is formed in the same manner as the second P-pole bus bar 5 and is joined to the metallicon electrode 1a on the other side of the second element 2. The elements 2 are connected in parallel by the second P-pole bus bar 5 and the second N-pole bus bar 6 in a state where the major axis direction is the vertical direction and a gap is provided between each of the second elements 2 (hereinafter referred to as “this”). In this way, a state in which the bus bars are connected in parallel is referred to as a second element unit for convenience).

  7 is a case made of resin (in this embodiment, PPS (polyphenylene sulfite) is used, but is not limited to this) and has an open top surface. 7 a is an opening from the inner bottom surface of the case 7. And a partition wall provided so as to rise between the first element 1 and the second element 2, and in the case 7, the first element unit and the second element The unit is accommodated with the major axis direction being the vertical direction, whereby the partition wall 7a is placed in a predetermined gap provided between the first element 1 and the second element 2. It is made to arrange | position to.

  8 is a mold resin filled in the case 7, and only the P-pole terminals 3a and 5a and the N-pole terminals 4a and 6a of the first element unit and the second element unit are on the upper surface. In this state, the first element unit and the second element unit are accommodated in the case 7 and resin-molded, and the mold resin 8 is used for the first element 1 and the second element 2. In this embodiment, an epoxy resin is used as the mold resin 8.

  The case mold type capacitor according to the present embodiment configured as described above accommodates an element formed in an oval cross-section in the case with the major axis direction vertical, and is filled with mold resin between the elements. With the configuration described above, even if an AC voltage or a DC voltage superposed with an AC voltage is applied to the element, a ripple current is generated, so that even if the element itself vibrates, the mold resin filled between the elements The vibration of the element is suppressed by the above, and each element is kept in an insulated state by the mold resin so that it does not come into contact with each other and is not short-circuited. By providing the partition wall disposed in the gap, the effect of suppressing the vibration of the element is further enhanced.

(Embodiment 2)
Hereinafter, the second and second embodiments of the present invention will be described.

  In the present embodiment, the configuration of the partition wall provided in the case of the case mold type capacitor described in the first embodiment with reference to FIG. 1 is partially different. Since it is the same as that of the first embodiment, the same reference numerals are given to the same parts and the detailed description thereof is omitted, and only different parts will be described below with reference to the drawings.

  2A to 2C are a plan sectional view, a front sectional view, and a side sectional view showing the configuration of a case mold type capacitor according to the second embodiment of the present invention. In FIG. The resin case 9a rises from the inner bottom surface of the case 9 toward the opening, and the partition wall 9b is provided so as to be positioned between the elements, and the thickness of both end portions of the partition wall 9a is increased. The thick portion 9b is provided only in the vicinity of the metallicon electrode 1a of the first element 1 and the metallicon electrode 2a of the second element 2.

  9c is an element mounting rib provided on the inner bottom surface of the case 9, on which the metallicon electrode 1a of the first element 1 and the metallicon electrode 2a of the second element 2 are mounted, respectively. 9, the first element unit and the second element unit are accommodated with the major axis direction vertical.

  The case mold type capacitor according to the present embodiment configured as described above is provided with thick portions at both ends of a partition wall provided on the inner bottom surface of the case so as to separate each element, and further on the inner bottom surface of the case. In addition to the effect obtained by the case mold type capacitor according to the first embodiment, the metallicon electrode, which is the part where the vibration of the element is the smallest, is provided on the partition wall by providing the element mounting rib for mounting the metallicon electrode of each element. By positioning and fixing with the thick portion and the element mounting rib, the vibration of the element can be made difficult to propagate to the outside.

  The case mold type capacitor according to the present invention has an effect of excellent vibration resistance, and is particularly useful as an automobile capacitor or the like.

(A) Plan sectional drawing which showed composition of case mold type capacitor by Embodiment 1 of the present invention, (b) Front sectional view, (c) Side sectional view (A) Plan sectional drawing which showed composition of case mold type capacitor by Embodiment 2 of the present invention, (b) Front sectional view, (c) Side sectional view (A) Front sectional view showing the configuration of a conventional case mold type capacitor, (b) Side sectional view

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 1st element 1a, 2a Metallicon electrode 2 2nd element 3 1st P pole bus bar 3a, 5a P pole terminal 3b, 5b Junction part 4 1st N pole bus bar 4a, 6a N pole terminal 5 2nd P pole bus bar 6 2nd N pole bus bar 7, 9 Case 7a, 9a Partition wall 8 Mold resin 9b Thick part 9c Element mounting rib

Claims (3)

A plurality of elements provided with a pair of electrodes on both end faces are connected in parallel with each other with a bus bar provided with a terminal portion for external connection at one end,
In a case mold type capacitor in which these are housed in a case and filled with a mold resin except at least the terminal portion of the bus bar,
The element is formed in an oval cross-section, and is accommodated in the case with the major axis direction being the vertical direction,
A plurality of partition walls filled with mold resin and thickened at least in the vicinity of the electrode of the element rise from the inner bottom surface of the case between the elements arranged in parallel. A case mold type capacitor. The case mold type capacitor according to claim 1 , wherein an element mounting rib on which a pair of electrodes provided on both end faces of the element is placed is provided on the inner bottom surface of the case. The case mold type capacitor according to claim 1, wherein two or more types of elements having different functions are connected in parallel and accommodated in the case.

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