JPH0982565A - Winding type of metallized film capacitor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To materialize the function of preserving security which enables safe use at high temperature in a winding type of metallized film capacitor. SOLUTION: Metallikon parts 11 are made on both sides of a capacitor element 6 made by winding a dielectric film where a deposition electrode is made, and lead wires 1 and 1' are bonded to this, and those are molded with resin. The shrinkage factor of the dielectric film is 0.3% or over in TD direction, and the area of the bonding parts of the lead wires 1 and 1' is 0.5-50mm<2> , and the adhesive strength is 0.01-10kg/mm<2> , and besides the rate r/R of the distance 4 from the center of the winding of the capacitor element 6 to the center of the bonding part 2 of the lead wires 1 and 1' to the radius R of winding of the capacitor element 6 is made 0.3<=r/R<=0.95. When it gets to high temperature, the capacitor element 6 is transformed caused by the shrinkage of the dielectric film, and the lead wires 1 and 1' peel easily off the metallikon part 11, and the capacitor element 6 is cut off the circuit.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dry-wound metallized film capacitor used for AC applications.

[0002]

2. Description of the Related Art Conventionally, in a wound type metallized film capacitor, various metal wires and lead wires of metal foil are generally used.
It was adhered to the metallikon part by welding technology such as spot welding or technology such as soldering. In this case, from the viewpoint of setting the contact resistance low, it has been considered that a better design is to set the bonding area and the bonding strength as large as possible.

On the other hand, by molding with a curable resin and using the electrodes of the metallized film as divided electrodes, or along the edge of the metallized electrode of the divided electrodes, strip-shaped, linear, or intermittent other A capacitor with a safety function has been developed and put into practical use in combination with the provision of a fuse part whose current capacity is set smaller than that of the electrode part.

[0004]

However, if the temperature of the capacitor exceeds a high temperature, particularly 100 ° C., the destruction of the capacitor due to a heat factor becomes remarkable, and a highly reliable security function sufficient to solve this problem is required. Became. An object of the present invention is to provide a wound metallized film capacitor which can realize a safety function that can be safely used at high temperature.

[0005]

A wound metallized film capacitor according to claim 1 comprises a first dielectric film, a first vapor deposition electrode, a second dielectric film, and a second vapor deposition electrode. A wound metallized film capacitor in which a metallikon portion is formed on both sides of a capacitor element which is sequentially stacked and wound, and a lead wire is adhered to the metallikon portion and which is resin-molded, the first and second dielectric films being provided. shrinkage is 0.3% or more in the TD direction is 0.5 to 50 mm ² area of the adhesive portion with respect to metallikon portion of the lead wire, the adhesive strength is 0.01 to 10 / mm ^2, and , Distance r from the winding center of the capacitor element to the winding radius R of the capacitor element to the center of the bonded portion of the lead wire
Ratio r / R of 0.3 ≦ r / R ≦ 0.95. With this configuration, when the temperature becomes abnormally high, a certain deformation of the capacitor element due to the contraction of the dielectric film occurs, the lead wire is easily peeled from the metallikon part, the peel distance is secured, and as a result, the capacitor element is Disconnected from the circuit. As described above, the abnormal high temperature spontaneously causes the disconnection state, and the safety of the capacitor can be achieved.

According to the wound type metallized film capacitor of the second aspect, in the wound type metallized film capacitor of the first aspect, the lead wire is spot-welded to the metallikon portion. This spot welding is more preferable in terms of disconnection. The wound metallized film capacitor according to claim 3 is the wound metallized film capacitor according to claim 1 or 2, wherein at least one of the first and second vapor deposition electrodes is a divided electrode. As a result, the security of the conventional split electrode can be obtained.

A wound metallized film capacitor according to a fourth aspect is the wound metallized film capacitor according to the third aspect, in which the divided electrodes are strip-shaped, linear, or along the edge of the metallized electrode. Fuse portions are provided intermittently so that the current capacity is set smaller than that of the other electrode portions. As a result, the security can be obtained by the conventional divided electrode provided with the fuse portion.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view showing a safety function of a wound metallized film capacitor according to an embodiment of the present invention. 1, 1'is a lead wire, 2 is a bonding portion of the lead wires 1, 1 ', and 3 is a cured wire. 4 is a case, 5 is a case, 5 is a void formed by deformation of the capacitor element 6, 10 is a winding core portion, and 11 is a metallikon portion.

This wound metallized film capacitor is
Metallicon parts 11 are formed on both sides of a capacitor element 6 wound with a dielectric film having vapor-deposited electrodes, and lead wires 1 and 1'are bonded to the metallicon parts 11 and put in a metal or resin case 4. And is molded with the curable resin 3. Its characteristic is that the shrinkage rate of the dielectric film is 0.3% or more in the TD direction, the area of the adhesive portion 2 of the lead wires 1 and 1 ′ to the metallikon portion 11 is 0.5 to 50 mm ² , and the adhesive strength is Is 0.01 to 10 kg / mm ² ,
Further, the ratio r / R of the distance r from the winding center of the capacitor element 6 to the center of the bonding portion 2 of the lead wires 1, 1 ′ with respect to the winding radius R of the capacitor element 6 is 0.3 ≦ r / R ≦
That is 0.95.

A specific example of the structure of this winding type metallized film capacitor will be described below with reference to FIGS. 2 to 5 together with its manufacturing method. First, as a dielectric film, polypropylene having a thickness of 6 μm (hereinafter referred to as PP
Abbreviated) is used. The heat shrinkage rate of this PP film is MD (Machi) in the length direction of the film.
TD (Tr) which is 4.8% in the direction (ne Direction) and is a direction (width direction of the film) perpendicular to the MD direction.
0.6 in the direction
%Met. The heat shrinkage rate is basically DIN4063.
It is a value measured at 120 ° C./60 minutes according to 4. After vacuum-depositing aluminum on one surface of the PP film, a first single-sided metallized film having the divided electrodes 7 shown in FIG. 2 is obtained by a laser trimming technique. This single-sided metallized film has a margin portion 9 in which the divided electrodes 7 are not formed on the edge portion which is not subjected to metallikon. The vapor-deposited film resistance value of the divided electrodes 7 is 3.5Ω / □ on average, and the divided electrodes 7 have a current capacity higher than that of other electrode portions along the metal edge 12 of the electrode to be strip-shaped, linear, or intermittent. The fuse portion 8 is set to have a small value. The dimensions of each part in FIG. 2 are a = 0.8 mm, b = 0.6 mm,
c = 60 mm and e = 57 mm. On the other hand, although not shown, aluminum is vacuum-deposited on one side of a similar PP film to obtain a second one-side metallized film having vapor deposition electrodes formed thereon. The vapor deposition electrode of this second single sided metallized film is not segmented. The first and second single-sided metallized films thus obtained are stacked by a usual method and wound by a winder to obtain a capacitor element 6 (see FIG. 3).

Next, metallization is applied to both ends of the capacitor element 6 to form the metallikon portion 11. Then 1
After vacuum heat aging at 00 ° C / 15 hours, lead wires 1 and 1'of a metal foil having a thickness of 0.1 mm and a width of 5 mm are bonded to the metallikon portion 11 by spot welding (Fig. 3).
State). At this time, as shown in FIG. 4, when the radius of the capacitor element 6 is R and the distance from the center of the capacitor element 6 to the center point of the bonding portion 2 of the lead wires 1, 1 ′ is r, R =
At 18 mm and r = 12 mm, r / R is about 0.67. The electrical adhesion area by the spot welding (effective area in which the lead wires 1 and 1'electrically contact the metallikon portion 11) was about 12 mm ² . In this state,
As shown in FIG. 5, when the capacitor element 6 is fixed and a tensile strength test is performed in which a load is applied to the lead wires 1 and 1 ′ in the direction of arrow A to pull, the maximum value of the adhesive peel strength of each of the lead wires 1 and 1 ′ is obtained. (Total load for complete peeling) is 1.2 kg
And the adhesive strength of the lead wires 1 and 1'is 0.1 kg / m.
It was found to be m ² .

The capacitor element 6 to which the lead wires 1 and 1'are thus bonded is stored in a case 4 shown in FIG. 1, and an epoxy resin (manufactured by Matsushita Electric Works, Ltd., product name / main ingredient MDR-) is used as the curable resin 3. 4; Curing agent MDH-4) was vacuum-cast and thermally cured at 95 ° C. to complete a wound metallized film capacitor. Five roll-type metallized film capacitors were produced and placed in an AC313 hot air bath at 130 ° C.
When a voltage test of V (1.25 x 250 V) was performed,
It was confirmed that all of them were electrically opened within 5 hours and the capacitors were reliably separated from the power supply. When the capacitor is disassembled after the test, as shown in FIG. 1, the capacitor element 6 is deformed by the thermal contraction of the dielectric film, the void 5 is generated, and the lead wires 1 and 1 ′ are connected to the metallikon portion 1.
It was confirmed that it was peeled off from No. 1 and the security function was working. The deformation amount d in FIG. 1 due to the thermal contraction of the capacitor element 6 becomes 0.2 mm or more to perform the safety function, and becomes 0.8 mm or more to be sure.

As described above, according to this embodiment, when the temperature becomes abnormally high, the capacitor element 6 is deformed in a specific manner due to the contraction of the dielectric film.
1'is easily peeled from the metallikon portion 11, a peeling distance is secured, and as a result, the capacitor element 6 is separated from the circuit. As described above, the abnormal high temperature spontaneously causes the disconnection state, and the safety of the capacitor can be achieved.

In the embodiment of the invention described above, as shown in FIG. 2, at least one of the two poles of the capacitor is the split electrode 7, and the split electrode 7 is provided with the fuse portion 8 having a small current capacity. By combining with the conventional security function, a dual security function is formed, it is possible to deal with destruction in a wide range of destruction modes, and reliable security is realized, which is especially effective.

In this embodiment, the TD of the dielectric film is used.
It functions well when the shrinkage in the direction is 0.3% or more, and 0.4 to 2.5% is particularly preferable. A film larger than 2.5% can be used, but it may not be preferable because the capacitor characteristics tend to vary. Without limitation adhesion area particularly for metallikon portion 11 of the lead wire 1, 1 ', 0.5 to 50 mm ² are suitable, inter alia, 1 to 20 mm ² are preferred. 50m
If it is larger than m ^2, it is not preferable because the operation probability of the safety of the present invention is lowered, and if it is smaller than 0.5 mm ² , disconnection accident occurs during normal assembly and operation of the capacitor, which is not preferable. The adhesive strength can be measured with a push-pull gauge or the like and can be set between 0.01 and 10 kg / mm ² , and especially between 0.05 and 0.5 kg / mm ^2.
Is preferred. If it is larger than 10 kg / mm ^2, it is not preferable because the operation probability of security of the present invention is lowered.
If it is less than 0.01 kg / mm ² , disconnection occurs during normal assembly and operation of the capacitor, which is not preferable. In addition, the position of the center point of the adhesive portion 2 is
It is preferable that 0.3 ≦ r / R ≦ 0.95, but 0.5 or more is particularly preferable. If it is smaller than 0.3, the operation probability of security of the present invention is lowered, which is not preferable, and if it is larger than 0.95, the position is too large and the assembly yield is lowered, which is not preferable.

Further, the metallikon portion 1 of the lead wires 1, 1 '
The method for adhering to No. 1 is not particularly limited, but welding, spot welding, soldering, etc. are used, and spot welding is particularly preferable from the viewpoint of disconnectability. The curable resin 3 is preferably an epoxy resin, a urethane resin, an unsaturated polyester resin, a diallyl phthalate resin, a phenol resin, a melamine resin, a silicone resin, a urea resin, or the like. Among them, an epoxy resin and a urethane resin are suitable,
Epoxy resin is particularly preferable. The molding method is
The capacitor element 6 is housed in a metal or resin case 4 and cast. In this case, vacuum casting is preferable because the stability characteristics are more stable. As a resin curing method, a method such as heat curing, UV curing or EB curing can be applied. Alternatively, the capacitor element 6 may be coated by a dip or powder coating method and cured by a method such as heat curing, UV curing or EB curing.

The type of the dielectric film is not particularly limited, and PP, polyethylene terephthalate,
Polycarbonate, polyethylene, polystyrene, polyvinylidene fluoride, polyphenylene sulfide, etc. can be used alone or in combination.
Above all, a PP film is preferable in the present invention.
As the PP film, a film whose one side or both sides are subjected to corona treatment can be used.

Regarding the film, two single-sided metallized films may be combined and wound, or a double-sided metallized film and a non-metallized film may be combined and wound. The metallized film is mainly formed by vacuum vapor deposition, but the electrode material thereof is not particularly limited, but aluminum, zinc, tin, cobalt, nickel, silver, copper, gold, chromium, molybdenum, titanium, etc. These metals can be used alone or in combination to form an alloy or a multilayer. Particularly, in the present invention, aluminum and zinc are preferable, and aluminum is particularly preferable in terms of comprehensive characteristics.

The resistance value of the vapor deposition film is not particularly limited, and it is 1 to 1 because it is properly used depending on the electrode material and the purpose.
It is set in the range of 00Ω / □, but in aluminum,
The average value of the vapor deposition film resistance value is preferably 2 to 5 Ω / □, and particularly preferably 3 to 4 Ω / □. In addition, a so-called stepped electrode (an electrode whose membrane resistance value at the metallikon contact portion is designed to be lower than that of the main electrode portion) is particularly effective for the zinc electrode, and in this case, the main electrode portion has a resistance of 15 to 40 Ω / □ is preferable, and the metallikon contact portion is preferably 2 to 6 Ω / □.

The core 10 may be a resin-molded bobbin or a tubular core in which a film or sheet is wound several times. In this case, in particular, the heat deformation temperature of the member forming the portion (cylindrical or columnar portion) corresponding to the winding core in the central portion of the capacitor element is 90 to
It is particularly effective that the temperature is 140 ° C. from the viewpoint of improving the operability of the security function of the capacitor of the present invention.

The maximum permissible temperature of the capacitor of the present invention is specified according to the method of JIS C4908. In the present invention, the maximum permissible temperature is preferably higher than 100 ° C., preferably 105 ° C. or higher, and more preferably. By setting the temperature to be 115 ° C. or higher, a suitable effect can be expected. The upper limit of the maximum allowable temperature is not particularly limited, but 160 ° C. or lower is appropriate because of the heat resistance of the insulating material,
It is preferably 140 ° C. or lower.

[0022]

The wound metallized film capacitor of the present invention has a dielectric film shrinkage of 0.3% in the TD direction.
The area of the adhesive portion of the lead wire to the metallikon portion is 0.5 to 50 mm ² , and the adhesive strength is 0.01.
-10 kg / mm ² , and the ratio r / R of the distance r from the winding center of the capacitor element to the center of the bonding portion of the lead wire to the winding radius R of the capacitor element is 0.3.
By setting ≦ r / R ≦ 0.95, when the temperature becomes abnormally high, a specific deformation of the capacitor element due to the contraction of the dielectric film occurs, the lead wire is easily peeled from the metallikon portion, and the peel distance is Is ensured and, as a result, the capacitor element is disconnected from the circuit. As described above, the abnormal high temperature spontaneously causes the disconnection state, and the safety of the capacitor can be achieved.

It is more preferable to bond the lead wire to the metallikon portion by spot welding in terms of disconnection.
Further, by using at least one of the vapor deposition electrodes as a split electrode, and further by providing a fuse portion, the safety performance by the conventional split electrode and further the safety performance by the fuse portion can be obtained, and a double safety function can be obtained. It works and is effective.

[Brief description of drawings]

FIG. 1 is a sectional view showing a security function of a wound metallized film capacitor according to an embodiment of the present invention.

FIG. 2 is a plan view of a part of the metallized film according to the embodiment of the present invention.

FIG. 3 is a perspective view of a capacitor element according to an embodiment of the present invention.

FIG. 4 is a side view of the capacitor element according to the embodiment of the present invention.

FIG. 5 is a diagram showing a method of a tensile strength test of a lead wire of a capacitor element according to an embodiment of the present invention.

[Explanation of symbols]

 1,1 'Lead wire 2 Lead wire adhesion part 3 Curable resin 4 Case 5 Void 6 Capacitor element 7 Split electrode 8 Fuse part 9 Margin part 10 Core part 11 Metallicon part 12 Metallicon edge

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshiyuki Nishimori 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (4)

[Claims] 1. A first dielectric film and a first vapor deposition electrode.
The pole, the second dielectric film, and the second vapor deposition electrode in this order
Metallicon parts on both sides of the capacitor element wound next
And then attach the lead wire to this metallikon
It is a molded wound metalized film capacitor.
The shrinkage of the first and second dielectric films is TD
Is 0.3% or more toward the metal wire of the lead wire.
The area of the adhesive part to the inner part is 0.5 to 50 mm ²In
The adhesive strength is 0.01 to 10 kg / mm²Is
The capacitor element with respect to the winding radius R of the capacitor element.
From the winding center of the capacitor element to the center of the bonded part of the lead wire
The ratio r / R of the distance r to 0.3 ≦ r / R ≦ 0.9
Rolled metallized film condensate characterized in that
Sensor. 2. The wound metallized film capacitor according to claim 1, wherein the lead wire is spot-welded to the metallikon portion. 3. The wound metallized film capacitor according to claim 1, wherein at least one of the first and second vapor deposition electrodes is a divided electrode. 4. The divided electrode is provided with a fuse portion whose current capacity is set to be smaller than that of the other electrode portion in a strip shape, a linear shape, or an intermittent shape along the edge of the electrode to be metallyconstituted.
The described wound metallized film capacitor.