JP4967712B2 - Case mold type capacitor - Google Patents

Description

  INDUSTRIAL APPLICABILITY The present invention is used in various electronic equipment, electrical equipment, industrial equipment, automobiles, and the like. The present invention relates to a 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.

  3 is an exploded perspective view showing the structure of this type of conventional case mold type capacitor, FIG. 4 is a cross-sectional view taken along the line AA of FIG. 3, and in FIGS. 3 and 4, 10 is a metallized film capacitor. This capacitor 10 is a pair of metallized films in which metal vapor-deposited electrodes are formed on one or both sides of a dielectric film made of polypropylene, and the metal vapor-deposited electrodes are opposed to each other with the dielectric film interposed therebetween. In this state, a pair of extraction electrodes of P and N poles are provided respectively by forming metallicon electrodes with zinc sprayed on both end faces.

  Reference numeral 11 denotes a P-pole bus bar, and 11a denotes a P-pole terminal for external connection provided at one end of the P-pole bus bar 11. The P-pole bus bar 11 includes a plurality of capacitors 10 in close contact with each other. The P electrode 10 is joined to a P electrode formed on one end face, and the P electrode terminal 11a is pulled out above the capacitor 10 and exposed from a case 13 described later.

  Reference numeral 12 denotes an N-pole bus bar, and 12a denotes an N-pole terminal for external connection provided at one end of the N-pole bus bar 12. The N-pole bus bar 12 also includes a plurality of capacitors 10 in the same manner as the P-pole bus bar 11. The N pole electrodes formed on the other end face of each capacitor 10 are joined together in close contact, and the N pole terminal 12a is pulled out above the capacitor 10 and exposed from a case 13 described later. Thus, a plurality of capacitors 10 are connected in parallel connection by the P-pole bus bar 11 and the N-pole bus bar 12.

  Reference numeral 13 denotes a resin case, and reference numeral 14 denotes a mold resin filled in the case 13. The mold resin 14 is connected in parallel by the P-pole bus bar 11 and the N-pole bus bar 12. Is resin-molded in the case 13.

  The conventional case mold type capacitor configured as described above is a highly reliable case mold type excellent in mechanical strength, heat resistance and water resistance by molding the capacitor 10 in the case 13 with the mold resin 14. A capacitor could be provided (Patent Document 1).

  Further, it is known that the case mold type capacitor having such a configuration needs to be provided with a discharge resistor or a discharge circuit in order to discharge the electric charge stored in the capacitor 10 (Patent Document 2). FIG. 5 shows a specific example of a conventional case mold type capacitor to which such a discharge resistor is attached.

5A to 5D are a plan view, a front view, a side view, and a front sectional view of a conventional case mold type capacitor showing a specific example in which the above-described discharge resistor is attached. In FIG. Is a flat-shaped metallized film capacitor (hereinafter referred to as a capacitor), 16 and 17 are a pair of bus bars, 16a and 17a are terminals for external connection provided at one end of the bus bars 16 and 17, respectively. , 18 is an interior case, 19 is a mold resin filled in the interior case 18, 20 is an exterior case coupled to the interior case 18, and 21 is connected in parallel to the bus bars 16 and 17. It is the discharge resistance attached inside.
JP 2004-146724 A JP 2005-102416 A

  However, in the above conventional case mold type capacitor, since the discharge resistor 21 provided for the purpose of discharging the electric charge stored in the capacitor 15 is always in the ON state, the discharge resistor is always used regardless of whether it is normal or when the vehicle is stopped. 21 is activated and discharge is generated. Along with this discharge, a large amount of heat is generated in the discharge resistor 21. This heat generation increases as the voltage increases (and the capacity of the capacitor 15 increases during discharge). Met.

  The heat generated in the discharge resistor 21 propagates to the capacitor 15 near the discharge resistor 21 and the temperature of the capacitor 15 also rises, so that the heat resistance of the capacitor 15 may be adversely affected. .

  An object of the present invention is to solve such a conventional problem, and to provide a case mold type capacitor excellent in heat resistance, in which the heat generated by the discharge resistor does not have an adverse effect on the capacitor.

In order to solve the above-mentioned problem, the present invention is to connect a plurality of flat metallized film capacitors having metallicon electrodes on both end faces in parallel with a bus bar having a terminal portion on one end. A plurality of metallized film capacitors to be accommodated in the interior case. The interior case is made of resin and is molded with resin, and the interior case and an exterior case formed of aluminum in which a discharge resistor connected in parallel to the bus bar is coupled. Is formed by providing a horizontal arrangement row in which a plurality of flat minor axis directions are arranged in a straight line at both ends, and a vertical arrangement row in which a plurality of the same major axis directions are arranged in a straight line between the rows. together with the discharge resistor is disposed on an extension of, than metalized film capacitor closest lateral arrangement row to the discharge resistor, nearest the vertical to the discharge resistor The arcuate portion of the long diameter direction of the metalized film capacitor置列 those of the configurations in away from the discharge resistance.

  As described above, the case mold type capacitor according to the present invention has a structure in which the arcuate portion in the major axis direction, which is the portion where the flat metalized film capacitor is most susceptible to thermal damage, is kept away from the discharge resistance, so that the discharge resistance generates heat. Even so, the mold resin intervening before the heat propagates to the arcuate portion in the major axis direction of the metallized film capacitor will act as a buffer part that absorbs and dissipates the heat. The effect that it can suppress having a bad influence on the heat resistance of a chemical film capacitor is acquired.

  Moreover, the effect that size reduction is realizable by arrange | positioning a metallized film capacitor efficiently is also acquired.

(Embodiment)
Hereinafter, the invention described in the entire claims of the present invention will be described by using embodiments.

  1A to 1D are a plan view, a front view, a side view, and a front sectional view showing a configuration of a case mold type capacitor according to an embodiment of the present invention. FIG. 2 is an enlarged view of FIG. 1 and 2, reference numeral 1 denotes a flat metallized film capacitor (hereinafter referred to as a capacitor) having an oval cross section. The capacitor 1 is a dielectric film made of polypropylene. A flattening process in which the metallized film on which one side or both sides of the metallized film are formed is formed with a pair of metallized electrodes, the metallized electrode is wound in a state of being opposed to each other with a dielectric film, and the cross section is formed into an oval shape by pressing. And a pair of extraction electrodes of P and N poles are provided by forming metallized electrodes sprayed with zinc on both end faces, respectively.

  And the capacitor | condenser 1 comprised in this way has the horizontal arrangement | sequence row | line | column which arrange | positioned the flat type | formula minor axis direction linearly (five in this Embodiment) at both ends, and the flat major axis direction in the meantime Are arranged so as to be accommodated in an interior case 4 to be described later, in which a plurality of (three in the present embodiment) are arranged in a straight line.

  Reference numeral 2 denotes a P-pole bus bar, and 2a denotes a P-pole terminal for external connection provided at one end of the P-pole bus bar 2. The P-pole bus bar 2 has a plurality of capacitors 1 in close contact with each other. 1 is connected to a P-pole electrode formed on one end face of P. 1 and a P-pole terminal 2a is led out above the capacitor 1 and exposed from an interior case 4 described later.

  Reference numeral 3 denotes an N pole bus bar, 3a denotes an N pole terminal for external connection provided at one end of the N pole bus bar 3. The N pole bus bar 3 also includes a plurality of capacitors 1 in the same manner as the P pole bus bar 2. The N pole electrode formed on the other end face of each capacitor 1 is joined in a closely arranged state, and the N pole terminal 3a is pulled out above the capacitor 1 and exposed from an interior case 4 described later. Accordingly, a plurality of capacitors 1 are connected in parallel connection by the P-pole bus bar 2 and the N-pole bus bar 3.

  4 is a resin interior case, 5 is a mold resin filled in the interior case 4, and this mold resin 5 is connected in parallel by the P-pole bus bar 2 and the N-pole bus bar 3. The capacitor 1 is resin-molded in the interior case 4.

Reference numeral 6 denotes an aluminum outer case in which the inner case 4 is coupled, and 7 is a discharge resistor connected in parallel to the P-pole bus bar 2 and the N-pole bus bar 3 and mounted in the outer case 6. 7, the distance L <b> 1 to the arcuate portion in the major axis direction of the capacitors 1 in the vertically arranged row of the capacitors 1 in which a plurality of capacitors 1 are arranged in the interior case 4 is longer than the distance L <b> 2 to the capacitors 1 in the horizontally arranged row It is arrange | positioned by such a structure.

  The case mold type capacitor according to this embodiment configured as described above has a configuration in which the arcuate portion in the major axis direction, which is the portion where the flat capacitor 1 is most susceptible to thermal damage, is kept away from the discharge resistor 7. Even if the resistor 7 generates heat, the mold resin 5 interposed until the heat propagates to the arcuate portion in the major axis direction of the capacitor 1 plays a role of a buffer portion that absorbs and dissipates the heat. It is possible to prevent the heat resistance of the capacitor 1 from adversely affecting the heat resistance of the capacitor 1 and to dissipate the heat generated by the discharge resistor 7 in the outer case 6 by the configuration in which the discharge resistor 7 is attached to the outer case 6 made of aluminum. Therefore, it is possible to exhibit excellent heat resistance, and to efficiently arrange the capacitor 1 Ri is intended to achieve the significant effect of being able to realize downsizing.

In order to confirm the heat resistance of the case mold type capacitor according to the present embodiment thus obtained, the distance L1 from the discharge resistor 7 to the arc portion in the longitudinal direction of the capacitor 1 in the longitudinally arranged row is changed. Table 1 shows the results of measuring the effect of temperature on the capacitor 1 in comparison with a conventional product as a comparative example.

  The test conditions were as follows: applied voltage DC650 V, ambient temperature 85 ° C., ripple current 75 A, 5 KHz.

As is clear from Table 1, the case mold type capacitor according to the present embodiment has a configuration in which the distance L1 from the discharge resistor 7 to the arcuate portion in the longitudinal direction of the capacitors 1 in the longitudinally arranged rows is increased. 1 is less susceptible to thermal damage, and it can be seen that a more remarkable effect can be obtained by setting the distance L1 to 9 mm or more.

  The case mold type capacitor according to the present invention has the effects of suppressing the influence of heat generation due to the discharge resistance, exhibiting excellent heat resistance, and realizing downsizing, particularly for automobiles such as hybrid cars. It is useful as a field capacitor.

(A) top view, (b) same front view, (c) same side view, (d) same front sectional view showing the configuration of a case mold type capacitor according to an embodiment of the present invention An enlarged plan view of FIG. Exploded perspective view showing the configuration of a conventional case mold type capacitor Sectional drawing in the AA line of FIG. (A) Plan view, (b) Front view, (c) Side view, (d) Front sectional view showing the configuration of a case mold type capacitor with a conventional discharge resistor attached

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Metallized film capacitor 2 P pole bus bar 2a P pole terminal 3 N pole bus bar 3a N pole terminal 4 Interior case 5 Mold resin 6 Exterior case 7 Discharge resistance

Claims (1)

A plurality of flat metallized film capacitors each having an oval cross-section and provided with metallicon electrodes on both end faces are connected in parallel by a pair of bus bars having terminal portions for external connection at one end. An interior case in which the electrodes are accommodated in an upside down manner and resin-molded except at least the terminal portion of the bus bar, an exterior case formed of aluminum in which the interior case is coupled, and the pair of In a case mold type capacitor in which a discharge resistor connected in parallel to the bus bar is arranged , the plurality of metallized film capacitors accommodated in the interior case are arranged in a horizontal manner in which a plurality of flat minor axis directions are arranged in a straight line. A vertical arrangement row in which a plurality of flat major axis directions are arranged in a straight line is provided at both ends, and an extension of this vertical arrangement row Together with the discharge resistor is arranged above, than metalized film capacitor closest lateral arrangement row to the discharge resistor, the arc portion of the long diameter direction of the metalized film capacitor nearest the longitudinal arranged rows on the discharge resistor Case mold type capacitor that is kept away from discharge resistance .

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