JP3780975B2 - Capacitor manufacturing method and capacitor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a leg-mounted capacitor, and more particularly to a capacitor used in a motor-driven inverter circuit.
[0002]
[Prior art]
Conventionally, a capacitor is used for the purpose of smoothing drive system power such as an inverter circuit for driving a motor, and it is required to suppress inductance as the capacitor capacity increases.
[0003]
3A and 3B are diagrams showing a configuration of a conventional capacitor, wherein FIG. 3A is a diagram showing a plan view in section, and FIG. 3B is a diagram showing a front view in section. As shown in FIG. 3, the conventional capacitor has a single small capacitance type capacitor element 2, and the mounting leg 6 to which the capacitor is attached is also simply attached to the bottom surface side of the capacitor case 1. The upper part of the capacitor case 1 has an opening (casting surface 7), and a filling resin 4 for fixing the capacitor element 2 is cast from the opening (casting surface 7) to fix the capacitor element 2. It was. Further, the connection fitting 3 connected to the electrode portion 5 of the capacitor element 2 is exposed to the outside from the surface 7 on which the filling resin 4 is cast, and is connected to the outside.
[0004]
[Problems to be solved by the invention]
However, in the above conventional capacitor, the opening (casting surface 7) of the capacitor case 1 is on the side opposite to the mounting leg 6, and the connection fitting 3 that needs to be taken out for connection is provided with the opening ( It was to be taken out from the casting surface 7). Then, the connection fitting 3 that has come to the outside changes the connection location with the outside depending on the use situation, and when the connection location is on the side of the mounting leg 6 opposite to the casting surface 7, it is necessary to route the path. The connection fitting 3 that connects the electrode part 5 and the outside needs to be extended to the lower part of the capacitor case 1. Therefore, the subject that inductance became large has arisen. In particular, when used as a smoothing capacitor for a high-voltage inverter circuit for driving a motor for driving an automobile, if the inductance is large, it may hinder smoothing ripples of high-frequency currents of several hundreds to several tens of kilohertz. Became.
[0005]
Further, when it is necessary to increase the capacity of the capacitor as in the case of an inverter circuit for driving a motor for driving an automobile, a plurality of capacitor elements need to be built in the capacitor case. The capacitor element far from the external connection location (the leftmost capacitor element in FIG. 3B) has a large inductance, and it is necessary to suppress this. Furthermore, when the capacitor is mounted on an automobile, the mounting height may be limited due to space saving requirements. In such a case, taking out the connection fitting from the side opposite to the mounting leg of the capacitor case has a problem that the height of the capacitor becomes high as a whole, and it cannot be mounted on an automobile.
[0006]
The present invention solves such a problem and provides a capacitor that suppresses inductance without increasing the overall height of the capacitor.
[0007]
[Means for Solving the Problems]
In order to solve the above problems, the capacitor according to the present invention has a capacitor case with a built-in capacitor element and filled with resin, and has mounting legs on the resin casting surface side and diagonal positions. In addition, the surface on which the filling resin is cast should be on the same side as the leg mounting surface of the capacitor case, and the connection fitting that connects the outside and the electrode part of the capacitor element should be exposed to the outside from the surface on which the filling resin is cast. It is a thing.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to FIG.
[0009]
(Embodiment 1)
In FIG. 1, reference numeral 1 denotes a resin capacitor case, and 2 denotes a capacitor element. Reference numerals 3a and 3b are integrally connected fittings, 3a is a part built in the capacitor case 1, and 3b is a part protruding from the capacitor case to the outside. 4 is a filling resin such as an epoxy resin for fixing the capacitor element, 5 is an electrode portion, 6 is a resin casting surface side for attaching the capacitor to the outside, and is attached to each diagonal position, mounting legs, 7 is filling The casting surface for casting resin is shown.
[0010]
And the capacitor | condenser element 2 winds or laminates | stacks the metallized film which is not shown in figure, and has provided the electrode part 5 in the end surface. The connection fitting 3a is connected to the electrode portion 5, and the connection fitting 3b (connected integrally with 3a) is connected to an external device or the like, thereby electrically connecting the electrode portion 5 and the external device or the like. . The capacitor case 1 includes the entire capacitor element 2 and a connection fitting 3a, and is filled with a filling resin 4 and fixed. In FIG. 1, the bottom portion (casting surface 7) of the capacitor case 1 is an opening surface before resin filling, and this surface is a surface for casting the filling resin 4. Further, the connection fitting 3b protrudes from the casting surface 7 to the outside from the capacitor case 1.
[0011]
Further, as shown in FIG. 1, the capacitor case 1 has an attachment leg 6 so that it can be attached to an external device or the like with a screw or the like. Since the capacitor case 1 contains a plurality of capacitor elements 2, the case itself is large, and the mounting legs 6 are provided at four locations from the weight of the entire capacitor and the durability during impact, and have a shape extending in all directions.
[0012]
A method for manufacturing the above capacitor will be described.
[0013]
First, the connection fitting 3a connected to each electrode part 5 of the plurality of capacitor elements 2 is assembled to the electrode part 5 by welding or soldering. At this time, the connection fitting 3a is connected to a location close to the casting surface 7 in the electrode portion 5 (the lower portion of the electrode portion 5 in FIG. 1B). This is for shortening the length of the connection fittings 3a and 3b connecting the electrode part 5 and the external connection portion as much as possible. Here, the connection fittings 3a and 3b are formed so as to protrude from the opening (the casting surface 7) of the capacitor case 1 when an assembly part of the capacitor element 2 and the connection fitting 3 is inserted into the capacitor case 1. .
[0014]
Further, the assembly parts of the capacitor element 2 and the connection fittings 3a and 3b are inserted into the capacitor case 1 from the opening (casting surface 7) of the capacitor case 1, and supported by ribs provided inside the capacitor case 1. After holding, the filling resin 4 is cast from the casting surface 7 and fixed. At this time, the connection fitting 3b is in a state of protruding from the casting surface 7 to the outside.
[0015]
Then, the capacitor thus manufactured is fixed to the outside with a screw or the like (not shown) with the mounting surface of the mounting leg 6 aligned with the external mounting surface. Further, as shown in the figure, the connection fitting 3b that has been exposed to the outside is connected to an external connection terminal (not shown) on the same side as the mounting leg 6.
[0016]
As described above, when the capacitor case is directly attached to the capacitor case and the connecting part is connected to the outside on the same side as the attachment leg, the filling resin 4 for fixing the capacitor element 2 to the capacitor case 1 is used. The casting surface 7 for casting is placed on the same side as the mounting leg 6 and the connection fitting 3 is projected from the casting surface 7 until it is connected to an external device or the like of the connection fitting 3a, 3b. Can be shortened. Thereby, the inductance of the connection fittings 3a and 3b can be suppressed.
[0017]
Further, as another advantage of doing this, even if the height of each of the mounting legs 6 is different by performing the manufacturing work with the mounting surface of the mounting legs 6 facing upward (upside down in FIG. 1 (b)), The planar surface of the capacitor case 1 serves as a base and facilitates work.
[0018]
Further, it is necessary to change the capacitor capacity, and even if the height of the capacitor element is changed, the distance between the connection fittings 3a and 3b can be made the same by adjusting the height of the mounting leg 6, and the connection fitting 3a. The change in inductance due to 3b can be eliminated.
[0019]
FIG. 2 is a diagram showing an example in which the capacitor according to the present embodiment is used for smoothing an inverter circuit that drives a motor for driving a vehicle, where 21 is a DC power source such as a battery, and 22 is the present embodiment. , 23 is an inverter circuit, 24 is a motor, and 25 is an automobile.
[0020]
The capacitor shown in this embodiment can suppress inductance as described above in a capacitor that requires a large capacity, such as that used in an automobile that is driven by a motor using an inverter circuit. As shown in FIG. 3, it is connected to an inverter circuit 23 that drives a vehicle drive motor 24, and is used for smoothing a ripple current or the like of a high frequency current of several hundreds to several tens of kilohertz. Is suitable.
[0021]
In this embodiment, an example in which a plurality of capacitors are used to cope with a large-capacity capacitor has been described. However, the present embodiment is effective even with a single capacitor.
[0022]
Further, if the capacitor of the present invention is a metallized film capacitor formed by winding or laminating a metallized film, it is suitable for severe environmental conditions such as a rapid temperature change for automobiles, so that the inductance is further suppressed. In this respect, the effect of the present invention is great.
[0023]
【The invention's effect】
As described above, the present invention can increase the capacity and suppress the inductance by using a plurality of capacitor elements with a film capacitor to which the legs are attached.
[Brief description of the drawings]
1A is a cross-sectional view of a capacitor according to an embodiment of the present invention. FIG. 1B is a cross-sectional view of a front view of the capacitor according to an embodiment of the present invention. The figure which shows the structure which used the capacitor | condenser of the form for smoothing of the inverter circuit which drives the motor for a vehicle drive. [FIG. 3] (a) The figure which showed the top view of the conventional capacitor in cross section (b) Front view in cross section 【Explanation of symbols】
DESCRIPTION OF SYMBOLS 1 Capacitor case 2 Capacitor element 3a, 3b Connection metal fitting 4 Filling resin 5 Electrode part 6 Mounting leg 7 Casting surface 23 Inverter circuit 24 Motor 25 Automobile

Claims (8)

A capacitor element, an electrode portion provided at an end of the capacitor element, a connection fitting connected to the electrode portion, the capacitor element is embedded, the inside is filled with a resin, and on the resin casting surface side and each A capacitor manufacturing method comprising a capacitor case provided with mounting legs at diagonal positions , wherein the resin filling the capacitor case is cast from the same side as the surface on which the mounting legs are mounted, A method of manufacturing a capacitor, wherein the resin is mounted and manufactured so as to be exposed to the outside from the surface to be cast.   The method of manufacturing a capacitor according to claim 1, wherein a capacitor having a plurality of capacitor elements is manufactured. A capacitor element, an electrode portion provided at an end of the capacitor element, a connection fitting connected to the electrode portion, the capacitor element is embedded, the inside is filled with a resin, and on the resin casting surface side and each A capacitor case provided with a mounting leg at a diagonal position of the capacitor, the casting surface of the resin filling the capacitor case is on the same side as the surface on which the mounting leg is mounted, and the connection fitting is Capacitors that are exposed to the outside from the resin casting surface.   The capacitor according to claim 3, comprising a plurality of capacitor elements. A capacitor element, an electrode portion provided at an end of the capacitor element, a connection fitting connected to the electrode portion, the capacitor element is embedded, the inside is filled with a resin, and on the resin casting surface side and each A capacitor case provided with mounting legs at diagonal positions, and the casting surface of the resin filling the capacitor case is on the same side as the surface to which the mounting legs are attached, and the connection fitting is the resin casting An inverter circuit for driving a motor for driving an automobile using a capacitor for smoothing out from the surface to be driven.   6. The inverter circuit according to claim 5, wherein a capacitor having a plurality of capacitor elements is used for smoothing. A capacitor element, an electrode portion provided at an end of the capacitor element, a connection fitting connected to the electrode portion, the capacitor element is embedded, the inside is filled with a resin, and on the resin casting surface side and each A capacitor case provided with a mounting leg at a diagonal position of the capacitor, the casting surface of the resin filling the capacitor case is on the same side as the surface on which the mounting leg is mounted, and the connection fitting is An automobile equipped with an inverter circuit for driving an automobile driving motor using a capacitor for smoothing out from the resin casting surface.   The automobile according to claim 7, which is equipped with an inverter circuit using a capacitor having a plurality of capacitor elements for smoothing.

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