JP4076250B2 - Fixing method of smoothing capacitor of power converter - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electric device having a relatively large capacitor such as a smoothing capacitor on a circuit board, and more particularly to a power converter suitable as a general-purpose inverter device.
[0002]
[Prior art]
Usually, circuit boards are mainly used for the formation of electronic circuits, but many electronic components at this time are of surface mounting type, and their terminals are soldered to the circuit pattern. Thus, fixing to the circuit board can be obtained together with electrical connection.
[0003]
However, depending on the type of electronic component, there are components that are separately attached by hand, and such electronic components are used for electric devices such as power converters, sequencers, television receivers, washing machines, and the like. There is a smoothing capacitor.
[0004]
Among them, power converters such as inverter devices require a capacitor with a considerably large capacitance for smoothing. Therefore, as the main circuit capacitor, an aluminum electrolytic capacitor is usually used. Even in this case, the inertial mass of a large product having a diameter of 20 mm or more and a length of 40 mm or more is considerably large.
[0005]
Therefore, in the case of such a large-capacitance capacitor, if the lead wire (electrode terminal) is simply soldered to the circuit board, when vibration is applied, a large stress is generated in the soldered portion or the lead, resulting in metal fatigue. Since there is a possibility that the capacitor is raised and broken, and there is a possibility that the capacitor may come into contact with an adjacent component, it is necessary to separately fix the capacitor body to a fixing member such as a circuit board.
[0006]
Therefore, conventionally, in such a case, a filler such as silicon rubber is poured between the capacitor body and the fixing member, or the band is wound around the capacitor body, and both ends of the band are attached to the fixing member. It was fixed by attaching.
[0007]
[Problems to be solved by the invention]
The above-described prior art does not give consideration to the point that a special work is required for fixing the capacitor, and there is a problem that much cost and labor are required for fixing the capacitor.
For example, in the case of the prior art using a filler such as silicon rubber, a special tool is required for pouring the filler, and it takes a considerable time to solidify the filler, resulting in an increase in cost.
In addition, skill is required to keep the filling amount of the filler constant, otherwise there is a problem that the uniformity of quality cannot be maintained.
[0008]
Furthermore, when silicon rubber is used as the filler, the adhesive strength is reduced by heating, so an automatic soldering apparatus cannot be used.For this reason, after the soldering process of the circuit board, separately, There is a problem that an inefficient work that requires a capacitor fixing process is unavoidable.
[0009]
On the other hand, the conventional technique using a fixing band also has a problem that a special jig is required for winding the band and it takes a considerable time to wind the band.
An object of the present invention is to provide a method for fixing a smoothing capacitor of a power converter that makes it easy to attach a capacitor.
[0010]
[Means for Solving the Problems]
The above object is to fix the smoothing capacitor of a power converter having a smoothing capacitor on a circuit board, and adhere the smoothing capacitor to the circuit board using a double-sided adhesive tape whose adhesive force increases by heating , and then solder A heat treatment is performed on the double-sided adhesive tape by heat generated when the lead wire of the smoothing capacitor is soldered to the circuit board using an apparatus to increase the adhesive force, and the smoothing capacitor is fixed to the circuit board. Is achieved.
[0011]
With a double-sided adhesive tape or adhesive plate-like member, the capacitor can be fixed simply by pressing the capacitor against the fixing member such as a circuit board. Can be completed.
[0012]
In addition, since the double-sided adhesive tape can be cut with a very common tool such as scissors or a knife, it is not necessary to use a special tool.
Furthermore, as such a double-sided adhesive tape, for example, there is a structural tape “VHB” (trade name) manufactured by Sumitomo 3M Limited, which is easily available and inexpensive.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a method for fixing a main circuit capacitor of a power converter according to the present invention will be described in detail using the illustrated embodiment as an example.
FIG. 1 shows an embodiment in which the present invention is applied to an inverter device. In this figure, 1 is a capacitor, 2 is a fixing member, and 3 is a double-sided adhesive tape (also called double-sided adhesive tape). 2A is a diagram viewed from the side of the capacitor 1, and FIG. 2B is a diagram viewed from the bottom surface of the capacitor 1. FIG.
[0014]
The capacitor 1 is a so-called main circuit capacitor composed of a smoothing aluminum electrolytic capacitor provided in the main circuit of the inverter device. For example, the capacitor 1 is a large product having a diameter of 20 mm or more and a length of 40 mm or more. A lead wire (electrode terminal) 1a is provided, and a wiring 5 is connected by a connection fitting 4 to be connected to a main circuit of an inverter device (not shown).
[0015]
The fixing member 2 is a member in a predetermined portion in the casing of the inverter device, and is a part of a circuit board of the inverter device or a structure of the inverter device, for example, and functions to attach and hold the capacitor 1.
The double-sided adhesive tape 3 is a tape having an adhesive layer for adhesion on both sides. At this time, a predetermined elasticity in the thickness direction is obtained by adopting a sandwich configuration in which a sponge-like synthetic resin layer having a predetermined thickness is sandwiched. For example, the above-described structural tape “VHB” or the like is used.
[0016]
In order to attach the capacitor 1 to the fixing member 2, first, the double-sided adhesive tape 2 cut to a predetermined length is interposed between the side surface of the capacitor 1 and the fixing surface of the fixing member 2, and the capacitor 1 is fixed. Press against member 2.
At this time, in order to obtain the original adhesive performance of the tape, a pressing force recommended by the tape manufacturer (for example, 5 kgf / cm ² ) is applied.
As a result, the double-sided adhesive tape 1 changes its shape in the thickness direction in accordance with the shape of the main body of the capacitor 1, and securely adheres and fixes the capacitor 1 to the flat fixing member 2.
[0017]
After the capacitor 1 is adhesively fixed to the fixing member 2 in this way, the connection fitting 4 is fitted to the lead wire 1a and the wiring 5 is connected. An electrical connection to the circuit is obtained, and the mounting operation of the capacitor 1 can be completed.
[0018]
Therefore, according to this embodiment, the capacitor 1 can be attached to the fixing tip member 2 in a very short time, so that the injected silicon rubber is solidified as in the prior art in which the silicon rubber is poured. You can save time.
Further, unlike the prior art using a mounting band, a special tool for applying the band becomes unnecessary, and further, the band itself becomes unnecessary.
[0019]
Next, FIG. 2 shows another embodiment of the present invention. In the figure, reference numeral 6 denotes a circuit board, and other configurations are the same as those of the embodiment of FIG.
In the embodiment shown in FIG. 2, the capacitor 1 itself is not changed, but the fixing member is a circuit board 6. Therefore, the circuit board 6 has one surface, the lower side in this figure. A circuit pattern (printed wiring pattern) for forming the main circuit of the inverter device is formed on this surface, and the circuit board 6 itself is attached to a predetermined position in the inverter device.
[0020]
Then, the capacitor 1 is adhered to a predetermined position on the other surface of the circuit board 6, that is, the upper surface in this drawing, using a double-sided adhesive tape 3 as shown in the figure, and in the embodiment of FIG. Similarly, a predetermined pressing force is applied to fix the adhesive.
[0021]
At this time, the lead wire 1a of the capacitor 1 is molded as shown in the figure, and is previously formed on the circuit board 6 in accordance with the circuit pattern of the circuit board 6 when adhered using the double-sided adhesive tape 3. The leading end portion 1b of the lead wire 1a is inserted into the lead wire insertion hole as shown in the figure.
[0022]
Thereafter, the tip end portion 1b of the lead wire 1a is soldered to the circuit pattern as indicated by the soldering portion 6a, whereby the electrical connection of the capacitor 1 to the main circuit of the inverter device is achieved. To be given.
Therefore, the same effect as that of the embodiment of FIG. 1 can be obtained also by the embodiment of FIG.
[0023]
By the way, the adhesive strength of the double-sided adhesive tape 3 may be obtained by heating and then raising the temperature once after adhesion.
Therefore, in the embodiment of FIG. 1 and FIG. 2, after the capacitor 1 is adhered with the double-sided adhesive tape 3, the adhesive portion is heated to a predetermined temperature, and then returned to room temperature, thereby increasing the adhesive force. Mounting can be strengthened.
[0024]
Therefore, by heating once after adhesion, the necessary adhesive force can be secured without necessarily applying the pressure recommended by the manufacturer. As a result, the pressing force at the time of adhesion can be reduced, and installation work is easier. Can be.
[0025]
By the way, an automatic soldering apparatus may be used for manufacturing a circuit board.
Therefore, it is assumed that an automatic soldering apparatus is used for forming the soldering portion 6a in the embodiment of FIG.
In this case, the capacitor 1 is first adhered to the circuit board 6 via the double-sided adhesive tape 3 and then soldered by an automatic soldering apparatus. In this case, the manufacturer recommends that the capacitor 1 be adhered. For example, a pressure of about 1 kgf / cm ² may be applied.
[0026]
This is because the circuit board 6 is heated at the time of processing by the automatic soldering apparatus, and as a result, the adhesive tape 2 is temporarily brought to a high temperature. This is because it is stronger than the time, and an adhesive force equivalent to that obtained when pressure is applied in advance by applying the pressure recommended by the manufacturer can be obtained.
[0027]
Therefore, according to the embodiment in which the processing is performed by the automatic soldering apparatus after the adhesion as described above, the same effect as that of the first example can be obtained, and the capacitor is firstly connected in advance through the adhesive tape 2. 1 and the substrate 3a can be applied with a small amount of pressure, and only a soldering process is required, and there is no need to perform a separate heating process. Therefore, the operation is further simplified, and a large aluminum electrolytic capacitor is automatically soldered. Since mounting becomes possible, efficient and high workability can be obtained.
[0028]
By the way, in the above embodiment, the double-sided adhesive tape 1 having a predetermined elasticity in the thickness direction is used for the attachment of the capacitor 1, so that the side surface shape of the main body of the capacitor 1 is the attachment portion of the fixing destination member. Even if it is different from the surface shape of this, reliable adhesion can be obtained and fixed firmly.
[0029]
Therefore, as another embodiment of the present invention, instead of such a tape, as shown in FIG. 3, one surface is previously formed into a cylindrical depression surface in accordance with the side surface shape of the capacitor 1. A plate-shaped member, that is, a plate-shaped member 8 in which one surface 8a has the same surface shape as the mounting surface of the capacitor 1 and the other surface 8b has the same surface shape as the mounting surface of the fixing destination is used. You may make it attach to the fixation destination member 2 or the circuit board 6. FIG.
[0030]
In this case, a normal double-sided adhesive tape may be interposed between the both surfaces 8a and 8b of the plate-like member 8, and an adhesive layer for adhesion is formed on both surfaces in advance, and the adhesive layer is adhered thereto. You may do it.
Furthermore, even in this case, it goes without saying that heating may be performed after adhesion.
[0031]
According to the embodiment of the present invention, the capacitor can be fixed simply by pressing, so that it is not necessary to pour silicon rubber having a long solidification time as in the prior art, and the capacitor can be fixed in an extremely short time. In addition, there is no need to use a fixing band as in the prior art, and there is no need to use a special jig, so that the capacitor can be easily fixed.
In addition, according to the present invention, since the capacitor can be processed by the automatic soldering apparatus after the adhesive is attached, it is necessary to provide an electronic component fixing process using silicon rubber after the automatic soldering process as in the prior art. And very good working efficiency can be obtained.
[0032]
【The invention's effect】
According to the present invention, it is possible to provide a method for fixing a smoothing capacitor of a power converter that makes it easy to attach a capacitor.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing a fixed state of a capacitor according to an embodiment of the present invention.
FIG. 2 is an explanatory diagram showing a fixed state of a capacitor according to another embodiment of the present invention.
FIG. 3 is a perspective view showing an example of a plate member used in still another embodiment of the present invention.
[Explanation of symbols]
1 Capacitor (Main circuit capacitor)
1a Lead wire (electrode terminal)
1b Lead wire tip 2 Fixing tip member 3 Double-sided adhesive tape 4 having elasticity in the thickness direction Connection fitting 5 Wiring 6 Circuit board 6a Soldering part 8 Plate-like member 8a One side 8b The other side

Claims (3)

In the method of fixing the smoothing capacitor of the power converter having a smoothing capacitor on the circuit board,
After sticking the smoothing capacitor to the circuit board using a double-sided adhesive tape that increases the adhesive force by heating,
Heat treatment of the double-sided adhesive tape by heat generated when soldering the lead wire of the smoothing capacitor to the circuit board using a soldering device, to increase the adhesive force,
A method for fixing a smoothing capacitor of a power converter, wherein the smoothing capacitor is fixed to the circuit board. In the invention of claim 1,
The said double-sided adhesive tape has elasticity in the thickness direction, The fixing method of the smoothing capacitor of the power converter characterized by the above-mentioned . In the invention of claim 1,
A method for fixing a smoothing capacitor of a power converter, wherein the side surface of the smoothing capacitor and the circuit board are fixed by the double-sided adhesive tape .

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