JP6437880B2 - Film capacitors, coupled capacitors, inverters and electric vehicles - Google Patents

Description

  The present invention relates to a film capacitor, a coupled capacitor, an inverter, and an electric vehicle.

  For example, a film capacitor is formed by winding a metallized film having a dielectric film formed of a polypropylene resin film and an electrode film formed by vapor deposition on the surface of the dielectric film around a resin core. (Hereinafter referred to as a main body), and terminal electrodes made of metallicon are respectively provided at both ends in the axial length direction of the main body (see, for example, Patent Document 1).

JP 2013-138046 A

  However, the conventional film capacitor has a problem that the bonding strength between the main body and the terminal electrode is still low.

  An object of this invention is to provide the film capacitor which can improve the joint strength of a main body and a terminal electrode, a connection type | mold capacitor, an inverter, and an electric vehicle.

The film capacitor of the present invention includes a main body formed by winding a metallized film around a core made of an insulating material, and first and second terminal electrodes provided on both end surfaces of the main body in the axial length direction. The core body has a first end portion located in the axial length direction , a second end portion, and an outer peripheral surface located in the radial direction of the main body, and the first outer surface is provided with the first end portion. A first recess extending from the end in the axial length direction and not reaching the second end is provided, and a first anchor connected to the first terminal electrode is provided in the first recess . It is characterized by.

  The coupled capacitor of the present invention is formed by connecting a plurality of the above film capacitors with a bus bar.

  The inverter of the present invention is an inverter including a bridge circuit constituted by a switching element and a capacitor connected to the bridge circuit, and the capacitor is the film capacitor or the connected capacitor.

  The electric vehicle of the present invention includes a power source, the inverter connected to the power source, a motor connected to the inverter, and wheels driven by the motor.

According to the film capacitor of the present invention, the first concave portion that extends in the axial length direction from the first end located in the axial length direction and does not reach the second end portion is provided on the outer peripheral surface in the radial direction of the core body. And since the 1st anchor part connected with a 1st terminal electrode is provided in this 1st recessed part, the joint strength of a main body and a terminal electrode can be improved.

The structure of a film capacitor is shown typically, (a) is a side view, (b) is a developed perspective view. (A) is a cross-sectional view of the film capacitor, (b) is a side view showing a state in which the first anchor portion is provided on the outer peripheral surface of one end portion in the axial direction of the core body, and (c) is the outer periphery of the core body. It is a longitudinal cross-sectional view which shows the state which the 1st anchor part and electrode film of the surface have connected. The form which has a connection layer in the end surface of a core is shown, (a) is a side view, (b) is a longitudinal cross-sectional view. The form which has an anchor part in the outer peripheral surface of the both ends of a core is shown, (a) is a side view, (b) is a longitudinal cross-sectional view. It is a perspective view which shows a connection type capacitor typically. It is a schematic block diagram for demonstrating the structure of an inverter. It is a schematic block diagram which shows an electric vehicle.

  1A and 1B show a configuration of a film capacitor A, in which FIG. 1A is a side view and FIG. 1B is a developed perspective view schematically. The film capacitor A of FIG. 1 has a core body 6 made of an insulating material in a state where two kinds of metallized films 5a and 5b each having electrode films 3a and 3b are laminated on the main surfaces of the dielectric films 1a and 1b. And a main body 9 wound around. First and second terminal electrodes 11a and 11b are respectively provided on both end faces of the main body 9 in the axial length direction L of the core body 6, and the first terminal electrode 11a is connected to the electrode film 3a and the second terminal The electrode 11b is connected to the electrode film 3b.

  In FIG. 1 (b), the thicknesses of the dielectric films 1a and 1b and the electrode films 3a and 3b are shown as thicker as possible to facilitate understanding. In FIG. 1B, the description of the first and second terminal electrodes 11a and 11b is omitted.

  An electrode film 3a is formed on the dielectric film 1a so as to form an exposed portion 20a of the partial dielectric film 1a to form a metallized film 5a. The partial dielectric film 1b is formed on the dielectric film 1b. The metal film 5b is formed by forming the electrode film 3b so as to form the exposed portion 20b, and these are shifted slightly in the width direction and laminated and wound around the core body 6 as shown in FIG. ing.

  Then, when the metallized films 5a and 5b are laminated and wound around the core body 6, pressure is applied, and as shown in FIG. 2 (c), gaps (exposed portions 20a and 20b) are formed between the dielectric films 1a and 1b. In the part S1, the dielectric films 1a and 1b are joined together to eliminate a gap, and one side of the electrode films 3a and 3b in the axial length direction L is covered with the dielectric films 1a and 1b. The second terminal electrode 11b is insulated, and the electrode film 3b and the first terminal electrode 11a are insulated.

  Further, a portion S2 having a gap between the dielectric films 1a, 1b and the electrode films 3a, 3b (a portion shifted in the width direction of the metallized films 5a, 5b) remains, and the first, By arranging the material constituting the second terminal electrodes 11a and 11b, the first terminal electrode 11a is connected to the electrode film 3a, and the second terminal electrode 11b is connected to the electrode film 3b.

  As shown in FIG. 2, four first anchor portions 13 extending in the axial length direction L are provided on the outer peripheral surface of the one end portion of the core body 6 in the axial length direction L, and these first anchors are provided. The end face of the portion 13 on the side in the axial direction L is connected to the first terminal electrode 11a.

2A is a cross-sectional view taken along line 2a-2a in FIG. 2B. In FIG. 2C, the core body 6 is shown as a side surface, and the periphery of the core body 6 is shown as a cross section. It is a figure. As shown in FIG. 2, the core body 6 is made of, for example, a resin and has a cylindrical shape, and the end surface in the axial length direction L has a circular shape. Needless to say, the core body 6 may have a cylindrical shape, or may have an elliptic cylinder shape or an elliptic cylinder shape. In the cross-sectional view of FIG. 2C, the metallized films 5a and 5b are wound so as to have a total of three electrode films 3a and 3b, but it goes without saying that four or more layers may be used. is there.

  The first anchor portion 13 is formed of, for example, a conductive material in the four groove-like recesses 7 extending in the axial length direction L formed at a predetermined interval on the outer peripheral surface of one end portion of the core body 6. Metal materials (including alloys) are arranged.

  As shown in FIG. 2A, the cross-section of the recess 7 in the direction orthogonal to the axial length direction L has a concave curved bottom, and the cross-sectional shape of the first anchor portion 13 in the recess 7 is A convex curved inner surface corresponding to the bottom surface and a convex curved outer surface continuous with the outer peripheral surface of the core 6 are formed. The cross-sectional shape of the recess 7 is not particularly limited, but in particular, it is difficult for stress to be applied to the metallized films 5 a and 5 b that the outer surface is a convex curved surface continuous with the outer peripheral surface of the core body 6. This is desirable.

  In addition, the first anchor portion 13 is provided in the groove-like recess 7 extending in the axial length direction L. However, the recess 7 is formed in the outer peripheral direction of the core body 6 (with the axial length direction L and the length in the axial length direction L). A concave portion having a long length (in the direction perpendicular to the vertical axis) may be used. In this case, the first anchor portion 13 has a shape corresponding to the shape of the concave portion 7.

  Furthermore, the 1st anchor part 13 is connected to the electrode film 3a of the metallized film 5a, as shown in FIG.2 (c). The four first anchor portions 13 need not be, the first anchor portions 13 may be 1 to 3, 5 or more, and the outer peripheral surface of one end portion of the core body 7 may be It may be an annular body formed on the entire surface so as to surround it.

  It is desirable that the metal material constituting the first anchor portion 13 is the same as the metal material constituting the first and second terminal electrodes 11a and 11b. The first and second terminal electrodes 11a and 11b are preferably made of one metal material selected from, for example, zinc, aluminum, copper, and solder.

  Next, a method for manufacturing the film capacitor A will be described. First, for example, a polyarylate resin to be used as the dielectric films 1a and 1b is prepared. As a solvent for slurrying the polyarylate resin, for example, one kind selected from cyclohexane, ethylcyclohexane, toluene, xylene, chloroform and tetrahydrofuran is prepared.

  When forming the dielectric films 1a and 1b, for example, a PET film is prepared as a base material, and the above-described polyarylate resin is dissolved in a specific solvent to prepare a slurry, which is formed on the PET film. The dielectric films 1a and 1b are obtained through a drying process. For film formation, a kind of molding method selected from a doctor blade method, a die coater method, a knife coater method and the like is used.

  Next, electrode films 3a and 3b are formed by vapor-depositing metal components such as zinc and aluminum on the surfaces of the obtained dielectric films 1a and 1b, and the dielectric films 1a and 1b formed with the electrode films 3a and 3b. The metallized films 5a and 5b are prepared.

  Further, for example, a cylindrical resin core body 6 is prepared, four concave portions 7 are formed at one end portion in the axial length direction L of the core body 6, and a metal material is placed in the concave portion 7. The first anchor part 13 is formed by vapor deposition. The metallized films 5a and 5b are wound around the core body 6 having the first anchor portion 13 as shown in FIG. 1B to obtain the main body 9 of the film capacitor A.

Next, as shown in FIG. 2C, first and second terminal electrodes 11a and 11b are formed on the end surfaces of the body 9 where the electrode films 3a and 3b are exposed. For the formation of the first and second terminal electrodes 11a and 11b, for example, metal spraying (metallicon), plating, or the like is suitable. Next, the film capacitor A can be obtained by surrounding the surface of the main body 9 on which the first and second terminal electrodes 11a and 11b are formed with an exterior member.

  In such a film capacitor A, for example, on the end face in the axial length direction L of the main body 9 formed by winding the metallized films 5a and 5b around the outer periphery of the core body 6 having the first anchor portion 13 in the concave portion 7, for example By forming the first and second terminal electrodes 11a and 11b, the electrode films 3a and 3b are connected to the first and second terminal electrodes 11a and 11b, and the first terminal electrode 11a and the first anchor portion are connected. 13 can be joined to improve the joining strength between the first terminal electrode 11a and the main body 9 (core body 6).

  Moreover, in the said form, since the 1st anchor part 13 and the electrode film 3a are connected, the electrical connection reliability of the terminal electrode 11a and electrode film 3a which consist of the conventional metallicons can be improved.

  FIG. 3 shows another form of the film capacitor A. In this form, a connection layer made of a conductive material connected to the first anchor portion 13 is formed on one end face in the axial length direction L of the core body 6. 15 is provided. That is, a connection layer 15 is provided on one end face in the axial length direction L of the core body 6, and this connection layer 15 covers the one end face in the axial length direction L of the first anchor portion 13 to connect doing.

  The connection layer 15 is a vapor deposition film of a metal material (including an alloy), and the metal material constituting the connection layer 15 is the same as the metal material constituting the first anchor portion 13, that is, the first and second terminals. It is desirable that the material is the same as that of the electrodes 11a and 11b.

  In such a film capacitor A, since the terminal electrode 11a made of metallicon has a low bonding force to the core body 6 made of resin, the connection layer 15 is formed in advance on the end surface of the core body 6 by vapor deposition. In this step, the first terminal electrode 11a made of metallicon is formed on one end face of the core body 6 and in the vicinity thereof, so that the bonding strength between the terminal electrode 11a and the main body 6 can be improved.

  Although not shown, a concave portion is formed in the axial length direction on one end face of the core body 6 in FIGS. 2 and 3, and a columnar conductor is formed by vapor deposition in the concave portion, and the first terminal electrode 11a or You may make it connect with a connection layer. In other words, the columnar conductor may be embedded in one end face of the core body 6. In this case, the bonding strength between the first terminal electrode 11a and the main body 9 can be further improved.

  FIG. 4 shows still another form of the film capacitor A. In this form, as shown in FIG. 2, the first terminal electrode is formed on the outer peripheral surface of one end portion in the axial length direction L of the core body 6. The first anchor portion 13 connected to 11a and the second anchor portion 17 connected to the second terminal electrode 11b on the outer peripheral surface of the other end portion in the axial length direction L of the core body 6 are further provided. ing. The length of the second anchor portion 17 in the axial length direction L is adjusted to be short so as not to connect to the electrode film 3a. The surface of the second anchor portion 17 may be covered with an insulating film to insulate it from the electrode film 3a.

  In such a film capacitor A, in addition to the effect of the film capacitor A of FIG. 2, the terminal electrode 11b made of metallicon and the second anchor portion 17 are bonded, and the bonding strength between the terminal electrode 11b and the main body 9 is increased. It can be improved. In this embodiment, the connection layer 15 shown in FIG. 3 can be provided so as to be connected to the second anchor portion 17.

FIG. 5 is a perspective view schematically showing the configuration of the coupled capacitor C. FIG. In FIG. 5, the case and the resin for molding are omitted for easy understanding of the configuration. The coupled capacitor C of this embodiment has a configuration in which a plurality of film capacitors A are connected in parallel by a pair of bus bars 21 and 23. The bus bars 21 and 23 are composed of terminal portions 21a and 23a for external connection and lead terminal portions 21b and 23b connected to the terminal electrodes 11a and 11b of the film capacitor A, respectively.

  When the film capacitor A described above is applied to the connection type capacitor C, the connection type capacitor C having a high bonding strength between the main body and the terminal electrode can be obtained.

  The coupled capacitor C shown in FIG. 5 is arranged in the direction of the major axis of the cross section of the film capacitor A. In addition to this, the film capacitor A is stacked in the direction of the minor axis of the cross section. However, the same effect can be obtained.

FIG. 6 is a schematic configuration diagram for explaining the configuration of the inverter. FIG. 6 shows an example of an inverter D that generates alternating current from direct current. As shown in FIG. 6, the inverter D of the present embodiment includes a switching element (for example, an IGBT (Insulated Gate Bipolar Transistor)).
) And a diode, and a capacitor 33 disposed between the input terminals of the bridge circuit 31 for voltage stabilization. Here, the film capacitor A or the connected capacitor C is applied as the capacitor 33.

  The inverter D is connected to a booster circuit 35 that boosts the voltage of the DC power supply. On the other hand, the bridge circuit 31 is connected to a motor generator (motor M) serving as a drive source.

  FIG. 7 is a schematic configuration diagram showing an electric vehicle. FIG. 7 shows an example of a hybrid vehicle (HEV) as the electric vehicle E.

  In FIG. 7, reference numeral 41 denotes a driving motor, 43 denotes an engine, 45 denotes a transmission, 47 denotes an inverter, 49 denotes a power source (battery), and 51a and 51b denote front wheels and rear wheels.

  This electric vehicle E mainly has a function of transmitting the output of the motor 41 or the engine 43 as a drive source, or both to the pair of left and right front wheels 51a via the transmission 45, and the power source 49 is connected to the motor via the inverter 47. 41.

  In addition, the electric vehicle E shown in FIG. 7 is provided with a vehicle ECU 53 that performs overall control of the entire electric vehicle E. The vehicle ECU 53 receives a drive signal corresponding to the operation of the driver or the like from the electric vehicle E such as an ignition key 55, an accelerator pedal (not shown), and a brake. The vehicle ECU 53 outputs an instruction signal to the engine ECU 57, the power source 49, and the inverter 47 as a load based on the drive signal. The engine ECU 57 controls the rotational speed of the engine 43 in response to the instruction signal and drives the electric vehicle E.

  For example, when the inverter D in which the film capacitor A or the connection type capacitor C is used as the capacity unit 33 is used as the inverter 47 of the electric vehicle E as shown in FIG. 7, the film capacitor A or the connection type capacitor C is connected. Since it is highly reliable, current control of a control device such as an ECU mounted on the electric vehicle E can be made more stable.

  In addition, the inverter D of this embodiment can be applied not only to the hybrid vehicle (HEV) described above but also to various power conversion application products such as an electric vehicle (EV), a fuel cell vehicle, an electric bicycle, a generator, and a solar cell. .

1a, 1b ··· Dielectric films 3a and 3b · · Electrode films 5a and 5b · · Metallized film 6 ··· Core 7 · · · Recess 9 · · · Main body 11a · · · First terminal electrode 11b ··· Second terminal electrode 13: first anchor portion 15: connection layer 17: second anchor portion L: axial length direction

Claims (9)

A main body formed by winding a metallized film around a core made of an insulating material, and first and second terminal electrodes respectively provided on both end faces in the axial length direction of the main body;
The core has a first end portion, a second end portion located in the axial length direction , and an outer peripheral surface located in the radial direction of the main body, and the axial length from the first end portion to the outer peripheral surface. A first recess is provided that extends in a direction and does not reach the second end ;
A film capacitor, characterized in that a first anchor portion connected to the first terminal electrode is provided in the first recess. The film capacitor according to claim 1, wherein the first anchor portion is provided in the groove-shaped first recess extending in the axial length direction.   The film capacitor according to claim 1, wherein the first anchor portion is made of a conductive material and is connected to an electrode film of the metallized film. Extending from said second end to said outer peripheral surface of the front Kishintai to the axial direction, the second recess is provided spaced from the first recess with not reach the first end,
The film capacitor according to any one of claims 1 to 3, wherein a second anchor portion connected to the second terminal electrode is provided in the second recess. 5. The connection layer made of a conductive material connected to the first anchor portion is provided on the surface of the first end portion of the core body. Film capacitor.   A connected capacitor comprising a plurality of film capacitors according to claim 1 connected by a bus bar.   It is an inverter provided with the bridge circuit comprised by a switching element, and the capacity | capacitance part connected to this bridge circuit, Comprising: The said capacity | capacitance part is a film capacitor in any one of Claims 1 thru | or 5 An inverter characterized by. An inverter comprising a bridge circuit constituted by a switching element and a capacitor connected to the bridge circuit, wherein the capacitor is the coupled capacitor according to claim 6. .   An electric vehicle comprising: a power source; the inverter according to claim 7 or 8 connected to the power source; a motor connected to the inverter; and a wheel driven by the motor.

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