JPH0714749A - Capacitor equipped with improved safety function - Google Patents

Abstract

PURPOSE:To enhance safety furthermore by forming a fuse part of metallization between the tips of third margin parts disposed closely each other and then securing a metallized base body in a case using a resin. CONSTITUTION:A metallized base body 1 comprises a film base body 2 provided with a margin part consisting of a metallized region 3 and an unmetallized region. The margin part is formed of a first margin part 2a, a plurality of second margin part 2b extending from the first margin part 2a at a predetermined interval, and a plurality of third margin parts 2c extending from the second margin part 2b. A metailized fuse part 5 is formed between the tips of third margin parts 2c approaching closely each other. A wound metallized base body 1 is then fixed in an exterior case using a resin having the hardness A50-A80 at a room temperature (25 deg.C) regulated by JIS K6301.

Description

Detailed Description of the Invention

The present invention relates to a capacitor with a safety function, which is used as a capacitor for various electric devices, a capacitor for phase advancing, and the like. In particular, the present invention relates to a capacitor with a security function having further improved security.

[0002]

2. Description of the Related Art Conventionally, a wound-type capacitor has a structure in which a plurality of metallized substrates provided with vapor deposition films are wound on a substrate such as paper or plastic, and metal is sprayed on both electrode ends of the wound metallized substrate. After forming the metallikon part, connecting the lead wire to this metallikon part, housing the wound metallized base in an outer case, and fixing the wound metallized base in the outer case with a filling resin such as epoxy resin. Is manufactured by.
Further, means for effectively preventing smoke, ignition, combustion, etc. of a capacitor caused by poor insulation of a metallized substrate at the time of manufacturing a capacitor, capacity fluctuation due to voltage fluctuation or temperature change, etc. are already known. As such a preventing means, there is a means of forming a narrow metallized part by a non-metallized margin part in a part of the metallized region provided in the base and using this as a kind of fuse. This type of metallized substrate can be roughly classified into a split type as shown in FIG. 1 and a continuous type as shown in FIG.

The split-type metallized substrate (1) is composed of a metallized region (3) and a non-metallized margin part, and the non-metallized margin part is provided on one side in the longitudinal direction of the substrate.
A margin part (2a), a plurality of second margin parts (2b) extending from the first margin part (2a), and a plurality of third margin parts extending from the second margin part (2b). (2c), and the tip portions of the third margin portions (2c) adjacent to each other form a fuse portion (5) including a narrowed metallized portion. on the other hand,
In the continuous type metallized substrate, the split type metallized substrate (1)
Unlike the second margin part (22b), the metallized regions (23) are not completely isolated from each other, and the metallized regions (23) are electrically connected to each other.
The structure is substantially the same as that of the split type.

In any of the types, the fuse portion formed by the tips of the third margin portions adjacent to each other constitutes the weakest point portion in the metallized region and, for example, abruptly exceeds the withstand voltage. When the voltage fluctuates, a large current flows through the fuse, causing excessive heat generation.
Due to this heat generation, the metal in the fuse portion and its surroundings is scattered. In this way, by scattering only the fuse portion and the metal around the fuse portion, the metallized region having the fuse portion is separated from other metallized regions, causing a loss of function, and partially limiting the damage, Avoid damage to other metallized areas. As a result, the capacitor can retain the function as a capacitor (although the capacity is somewhat reduced) without producing smoke, ignition, combustion, or the like.

The safety of the capacitor having such a safety function is determined by the shape (eg, width and length) of the fuse portion, the resistance value of the metallized region forming the fuse portion, and the width (Y pitch) of the metallized region. ) Is said to greatly depend on. However, even when these factors are the same, there is a problem in that, when the security test is performed under the same condition, the security varies and the security becomes uneven.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a capacitor with a safety function, which has no variation in safety performance and further improved safety.

[0007]

The present inventor has diligently studied the cause of the above-mentioned variation in security, and as a result, the cause of this variation is used when the wound metallized substrate is housed in an outer case. Of the filled resin, that is, the hardness (or elasticity) of the filled resin interposed between the metallicon portion of the wound metallized substrate and the outer case, and this variation causes the hardness of the filled resin to change. The present invention has been found based on this finding that it can be solved reliably by selecting within a specific range.

That is, the present invention relates to a capacitor with a safety function, in which at least two metal vapor deposition substrates are wound and fixed by a filling resin in an outer case, wherein at least one of the metal vapor deposition substrates is a film-shaped one. The substrate has a metallized region and a margin portion composed of a non-metallized region, and the margin portion is (1) a first margin portion provided on one side in the longitudinal direction of the film substrate, 2) A plurality of second margin portions extended from the first margin portion at a predetermined interval, and (3) a plurality of third margin portions extended from the second margin portion, which are close to each other. The third
The present invention relates to a capacitor with a safety function, in which a fuse portion composed of a metallized portion is formed by the tips of the margin portions and the filling resin has a hardness of A50 to A85 according to JIS K6301 at room temperature.

The present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 shows a split-type metallized substrate 1 used for constructing a capacitor with security function according to the present invention.
It is shown. The metallized substrate 1 includes a film-shaped substrate 2, on which the metallized region 3 is formed.
And a margin portion composed of a non-metallized region. The margin portion includes (1) a first margin portion 2a provided on one side in the longitudinal direction of the film-shaped substrate and (2) a first margin portion. The plurality of second margin portions 2b extended from 2a at a predetermined interval, and (3) the plurality of third margin portions 2c extended from the second margin portion 2b, which are close to each other. The fuse portions 5 made of metallized portions are formed by the tips of the three margin portions 2c.

As the film-like substrate used here, any substrate conventionally used for such a capacitor can be used without particular limitation. For example,
Paper or a plastic such as polyester, polypropylene, polyethylene, polystyrene, polyimide, polyphenylene sulfide, polysulfone, or polycarbonate can be used. However, when paper is used as the substrate, it is preferable to apply a lacquer composed of acetyl cellulose, ethyl cellulose or the like to, for example, 1 to 2 μm in order to smooth the surface on the metallized side and reduce pinholes. . Further, before forming the metallized region described below, in order to improve the adhesion between the film-like substrate and the metal layer in the metallized region, a nuclear metal such as gold or silver is applied to the paper surface or the lacquer layer on the paper surface. You may attach a small amount.

The width and the thickness of the substrate vary depending on the application of the capacitor. For example, the width is 10 to 1
50 mm, preferably 20 to 100 mm, with a thickness of 2
It is 16 μm, preferably 3 to 10 μm. The metal forming the metallized region can be used without any particular limitation as long as it is a conventionally used evaporated metal. For example, zinc, aluminum, tin, copper, indium, etc. may be mentioned. The thickness of the metal film in the metallized region is generally 100.
~ 500 angstrom, preferably 150 ~
It is 300 angstroms. The metallized region and the margin portion composed of the non-metallized region are formed, for example, by vacuum-depositing metal on the substrate through a mask having a predetermined pattern. The width of the first margin portion 2a is generally 0.5 to 3.0 mm as long as sufficient insulation can be secured, and is determined by the working voltage. For example, voltage 250
In the case of V, it is 1.5 to 2.0 mm. Similarly, the width of the second margin portion 2b may be a conventionally used width. For example, it is generally 0.2 to 1.0 mm, preferably 0.
It is 2 to 0.5 mm. Also, the second margin portion 2b may extend to the opposite side of the film-shaped substrate with respect to the first margin portion 2a, as in the continuous metallized substrate (FIG. 2). It may also stop at a position close to the opposite side of the film substrate, as in (FIG. 1).

First margin portion 2a and second margin portion 2b
The angle between and is not particularly limited, but it is considered to be determined by the capacitance of the capacitor, the ease of forming the pattern of the vapor-deposited metal by the mask, and the like. Further, the connecting portion between the first margin portion 2a and the second margin portion 2b does not need to form a rectangular corner as shown in FIG. 1, and may be curved. In addition, the second margin portion 2b is connected to the first margin portion 2a at an acute angle of more than 90 °.
The metallized region formed by a and the two second margin portions 2b may be a parallelogram as a whole. Second
Similarly, the angle between the margin portion 2b and the third margin portion 2c is not particularly limited as long as the tips of the third margin portions 2c adjacent to each other form a metallized portion having a predetermined width. Can be designed to. The width of the third margin portion 2c can be set to a width that has been conventionally adopted. Generally, it is 0.2 to 2.0 mm, preferably 0.3 to 0.6 mm.

The width (d in FIG. 2) of the fuse portion formed by the tips of the third margin portions 2c which are close to each other can be used within the range conventionally adopted. Generally, the width of the fuse portion is 0.2 to 2.0.
mm, preferably 0.2 to 1.0 mm. If it is narrower than 0.2 mm, it will be difficult to set this width with high precision,
It becomes difficult to manufacture a highly accurate capacitor. An acute angle portion may be provided at a tip end portion of the third margin portion 2c forming the fuse portion 5 adjacent to the third margin portion 2c. With such a configuration, durability can be improved as compared with a smooth shape. The angle of the acute angle is generally 1
It is 0 ° to 90 °, preferably 10 ° to 60 °. If the number of acute-angled portions is 1 or more, the number is not particularly important.

From the edge of the film substrate 2 to the fuse portion 5
The interval up to can be set in the same manner as in the conventional case. Generally, it is 0.2 to 2.0 mm, preferably 0.3 to 1.5 mm. If this interval is narrower than the lower limit of the above range, the capacity decreases greatly during use, and durability is likely to decrease. On the other hand, if this interval is wider than the upper limit of the above range, safety is likely to decrease. Therefore, it is not preferable. In addition, you may provide the above-mentioned metallization area | regions and a margin part on both surfaces of the said film-shaped base | substrate. In Figure 2,
3 illustrates a continuous metallized substrate used to make the security capacitor of the present invention. In this continuous metallized substrate, the metallized regions (23) are not completely isolated from each other by the second margin portion (22b), and the metallized regions (23) are electrically connected. The structure is substantially the same as that of the split-type metallized substrate shown in FIG.

Such metallized substrates are, for example, filled
Through a mask made of masking oil
Can be manufactured by depositing metal on
It Conventionally used as a material for masks
What can be used is, for example, silicone oil,
-Masking oil such as fluoroalkyl polyether oil
used. The mask is formed by, for example, patterning the margin part.
Use a roll with a pattern corresponding to the surface formed on the surface
Then, deposit masking oil according to the pattern.
And transfer it to the substrate, and the pattern
Of the roll with the corresponding slit formed.
The masking oil vapor is passed through the slit from the inside.
Vapor deposition of masking oil on the substrate located outside the tool
There are ways. In addition, for example, polyimide film
After applying the masking tape consisting of
You may vapor-deposit. The substrate masked in this way is
It is then vapor deposited with metal. Pressure when depositing metal
Is generally 10^-1-10^-7Tall, preferably 1
0^-3-10 ^-FiveIt's Thor. Gold on the masked part
The metal is not vapor-deposited and the margin part consisting of the non-metal area is configured.
To be done. On the other hand, metal is evaporated on the unmasked area.
To form a metallized region.

The metallized substrate (3
As shown in FIG. 3, 1) are laminated in a state in which they are rotated by 180 ° in the horizontal direction, and the electrode parts (34) of the respective metallized substrates are arranged so as to face mutually opposite sides. After winding this laminated body and flattening it if necessary, metal is sprayed on both electrode parts (34) to form a metallikon part (39) as shown in FIG.
To form. Then, after connecting a lead wire (not shown) to the metallikon part, the lead wire (not shown) is housed in a predetermined outer case, the case is filled with a filling resin, and the outer case is covered with a lid as necessary to maintain the safety of the invention. Manufacturing functional capacitors. Of the multiple (usually two) metallized substrates that are wound, at least one must be a metallized substrate having divided metallized regions as described in FIG. 1 or 2. Note that all of the plurality of metallized substrates may be metallized substrates as shown in FIG. 1 or 2. As the metal used for the metallikon part, those conventionally used can be used. Generally, zinc, aluminum, solder (tin +
Lead), lead, etc. are used. From the viewpoint of weldability, the same metal as that used for the metallized substrate is preferable. As the injection method, the metal melted by heating is discharged from the nozzle to the electrode part (34).
There is a method of adhering it onto the compressed air flow by adhering to it, or a method of blowing metal while melting it with an arc.

A resin having a hardness of A50 to A85 at room temperature (25 ° C.) specified by JIS K6301 is used as a filling resin for fixing the wound metallized substrate in the outer case. The reason for this is as follows. When an overvoltage exceeding the withstand voltage is suddenly applied to the capacitor, a large current flows through the fuse part that forms the weakest point, which causes a large amount of heat to suddenly occur in the fuse part and The evaporated metal film is evaporated and scattered. Due to the pressure of the scattered gas generated at this time, the metallikon portion formed at the electrode end portion of the wound metallized substrate receives a strong force toward the outside (toward the outer case). When such an overvoltage is repeatedly applied, the electrical connection of the metallikon part gradually deteriorates, and before the safety of the capacitor functions, the metallikon part is damaged, heat is generated, and the capacitor smokes. Alternatively, the fuse is ignited, and the original security of the fuse portion does not function at all. That is, when the hardness of the filling resin is smaller than A50, the filling resin is too soft, and when the overvoltage is applied, the metallikon portion should be held flexibly at the electrode end portion against the outward force. I can't. On the other hand, the hardness is A8
When it is larger than 5, the elasticity is poor and similarly the metallikon portion cannot be flexibly held at the electrode end portion. In particular, the hardness of the filling resin is preferably A60 to A80.

Conventionally, an epoxy resin has been mainly used as a filling resin, and the hardness of such a filling resin conventionally used is usually A95 or more. On the other hand, in the present invention, as described above, A50 to A8
By using a resin in the range of 5 in a capacitor with a safety function, it was possible to obtain significantly better safety than a conventional capacitor with a safety function. JIS
The K6301 (5. hardness test) standard has been conventionally used to measure the hardness of vulcanized rubber, but in the capacitor with a safety function of the present invention, the resin used here is specified. Use this standard. The hardness according to this standard includes A-type and C-type measuring methods, but in the present invention, the A-type measuring method is used. In this method, the hardness of the resin is such that when the pressure surface of the tester is brought into contact with the surface of the resin layer having a predetermined thickness of 12 mm or more,
The distance at which the push needle protruding from the hole provided at the center of the pressing surface by the spring pressure is pushed back from the resin surface is recorded as a scale of hardness.

As the filling resin, urethane resin is particularly excellent in that it is excellent in water resistance and electric resistance and the hardness can be easily adjusted, and is preferable as the filling resin used in the capacitor with a safety function of the present invention. As such a urethane resin, for example, a diisocyanate having two NCO groups (OCN-R ₁ -NCO) is reacted with a glycol having two hydroxyl groups (OH-R ₂ -OH) to form a chain polymer. An elastic urethane resin obtained by forming and then crosslinking with a suitable crosslinking agent is mentioned. In order to impart elasticity to the urethane resin, it is necessary that the chain polyurethane does not have high cohesiveness. Therefore, R ₂ is preferably long-chain and has low polarity. For example, it is preferable that R ₂ is polyester or polyalkylene ether. When R ₂ is a long chain hydrocarbon, castor oil polyurethane and polybutadiene polyurethane are also preferable. A particularly preferable urethane resin is a resin which has excellent water resistance and electric resistance and whose hardness can be easily adjusted. Can be mentioned.

As the cross-linking agent, water, hydrogen sulfide, dimercaptan, diamine, etc. can be used when the reaction is carried out with an excess of isocyanate (when an isocyanate group is present at the terminal).
Dicarboxylic acids, glycols, polyols and the like are commonly used. When the reaction is carried out with excess hydroxyl groups, a crosslinking agent such as diisocyanate or polyisocyanate is generally used. Preferred specific resins include urethane resin SU-1800 manufactured by Sanyu Resin Co., Ltd. and the like.

The outer case can be used without limitation as long as it has been conventionally used for manufacturing a capacitor with a safety function. Usually, a cylindrical or rectangular outer case is used.

EXAMPLES The present invention will now be described in more detail with reference to examples. Example 1 A 5 μm thick polyester (polyethylene terephthalate) film was provided with a mask made of silicone oil so as to provide a 2 mm wide margin along one side of the film and a surface resistance of 7 ohms. , Zinc was vapor-deposited to produce a metallized substrate 1 having a 2 mm wide margin along one side of the film. Separately, a metallized substrate 2 having a margin portion shown in FIG. 2 is formed by depositing zinc on the same polyester film as described above using a mask made of silicone oil having a margin portion pattern as shown in FIG. (Width of fuse part: 0.5 mm)
Was manufactured. The width of these metallized substrates 1 and 2 is 38 mm
And rolled it up on a reel. Next, using one metallized substrate 1 and one metallized substrate 2, as shown in FIG. 3, the metallized substrate 1 and the metallized substrate 2 are laminated so that the margin portions formed along one side of the metallized substrate are opposite to each other. , Wind this,
A rolled metallized substrate was produced. Molten zinc is jetted from the nozzle to the end surface of this wound metallized substrate to form a metallikon part, and a lead wire is further connected to this metallikon part, which is then housed in a cylindrical outer case, and according to JIS K6301 A urethane resin having a mold hardness of A75 (SU-1800 manufactured by Sanyu Resin Co., Ltd.) was introduced into the outer case and cured to manufacture a capacitor with a safety function (14 μF). Eighteen capacitors with security function were manufactured. To evaluate the safety performance of capacitors with a safety function (test capacitors),
It was performed according to JIS C4908 (8.15 (2)). That is, while applying an AC voltage of 300 V to the capacitor to be tested,
Connect to a 22μF discharge capacitor charged at 0V, apply energy to the test capacitor once every 10 seconds, and measure the number of application times required for the capacitance of the test capacitor to reach zero. did. At this time, it was judged that the safety function was lost if the outer casing was cracked, the film substrate of the capacitor element was melted and blown out, or the capacitor smoked or ignited. The results are shown in Table 1 below.

Comparative Examples 1 to 3 Instead of the filling resin used in Example 1, hardness A9
Urethane resin of 5 or more (SU-150 manufactured by Sanyu Resin Co., Ltd.)
0) or an epoxy resin having a hardness of A95 or more (EX664 / H-390 manufactured by Sanyu Resin Co., Ltd.) is used (Comparative Examples 1 and 2: 18 each), and no filling resin is used (Comparison) For Example 3: 9 pieces), a test capacitor was manufactured, and the safety performance thereof was evaluated in the same manner as in Example 1. The results are shown in Table 1.

[0023]

[Table 1] Table 1 Filling resin Hardness Safety performance Average number of applications Presence or absence of defects (%) (times) Example 1 Urethane resin A75 18/18 = 100 785 Comparative example 1 Urethane resin> A95 7/18 = 38.9 710 Smoke generation 1 pieces melt blow 10 Comparative example 2 epoxy resin> A95 5/18 = 27.9 479 fuming four melt blowing nine Comparative example 3 as to ─── 0/9 = 0 394 melt blowing nine Note) the test temperature was 65 ° C. .

As can be seen from Table 1, in the case of the capacitor with safety function of the present invention, all capacitors with safety function (1
(00%) can be stably used for a long time (the average number of times of application is 785 times). On the other hand, in the case of the capacitor with safety function of Comparative Example 2 using the same urethane resin, its hardness is as high as A95 or higher, so 61% of the ones generate smoke or melt blowout on the way, and the safety property Was inferior. Also, the average number of times of application was smaller than that in Example 1. Furthermore, it can be seen that even when using a resin other than the urethane resin, if the hardness is too high or if the filling resin is not used, the safety and the average number of times of application are deteriorated. Incidentally, the polyester film as the film-shaped substrate generally has a poor operation rate of the safety function and has a difficulty in practical application, but by selecting the hardness of the filling resin in a predetermined range as described above, It turns out that the difficulties can be solved.

Example 2 A polypropylene film having a thickness of 4 μm was provided with a mask made of silicone oil so that a margin of 2 mm in width was provided along one side of the film, and the surface resistance was 3.
Zinc was evaporated to a thickness of 5 ohms to produce a metallized substrate 3 having a 2 mm wide margin along one side of the film. Separately, a metallized substrate 4 having a margin portion shown in FIG. 2 is formed by depositing zinc on the same polypropylene film as described above by using a mask made of silicone oil having a margin portion pattern as shown in FIG. (Fuse width: 0.5 mm) was manufactured. The widths of these metallized substrates 3 and 4 were adjusted to 38 mm and wound on a reel. Then, using one metalized substrate 3 and one metalized substrate 4, a capacitor with a safety function (25 μF) was manufactured in the same manner as in Example 1. Three capacitors with security function were manufactured. JIS C4908 is used to evaluate the safety performance of capacitors with a safety function (test capacitors).
(8.15 (2)). That is, while applying an AC voltage of 260 V to the test capacitor, connect it to a 44 μF discharging capacitor charged at 800 V, and apply energy to the test capacitor once every 10 seconds,
The voltage applied to the discharging capacitor was increased by 100 volts every 100 times until the capacitance of the capacitor to be tested became zero, and the number of times of application required up to that time was measured. At this time, it was judged that the safety function was lost if the outer casing was cracked, the film substrate of the capacitor element was melted and blown out, or the capacitor smoked or ignited. The results are listed in Table 2 below.

Comparative Example 4 Instead of the urethane resin used in Example 2, hardness A95
Epoxy resin above (made by Sanyu Resin Co., Ltd., EX664 / H-
390) was used, test capacitors were manufactured (5 capacitors were manufactured), and the safety performance thereof was evaluated in the same manner as in Example 2. The results are shown in Table 2.

[0027]

[Table 2] Table 2 Filling resin Hardness Safety performance Average number of applications Presence or absence of defects (%) (times) Example 2 Urethane resin A75 3/3 = 100 599 Comparative example 2 Epoxy resin> A95 2/5 = 40 374 Melt blowing 3 pieces Note) Test temperature is 85 ℃.

As can be seen from Table 2 above, in the case of the capacitors with a safety function of the present invention, all the capacitors with a safety function (100%) do not generate smoke or blow out in the middle of the process for a long period (average application). (The number of times is 599 times) It can be used stably. On the other hand, in the case of the capacitor with a safety function of Comparative Example 2, the hardness thereof was as high as A95 or higher, and therefore 60% of the capacitors with a safety function had melt blown out on the way, and the safety was poor. . Also, the average number of times of application was smaller than that in Example 1.

[Brief description of drawings]

FIG. 1 is a plan view of a split-type metallized substrate used in a capacitor with a security function according to the present invention.

FIG. 2 is a plan view of a continuous metallized substrate used in the capacitor with security function of the present invention.

FIG. 3 is a perspective view of one step of manufacturing a wound metallized substrate used to manufacture the capacitor with security feature of the present invention.

FIG. 4 is a perspective view of a wound metallized substrate having a metallikon portion used to manufacture the capacitor with security function of the present invention.

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Masahiro Terasaki 3465-1, Nakatsugawa, Nakatsugawa, Gifu Prefecture Honshu Paper Co., Ltd. Nakatsu Mill

Claims (1)

[Claims] 1. A capacitor with a security function, wherein at least two metal vapor deposition substrates are wound and fixed by a filling resin in an outer case, wherein at least one of the metal vapor deposition substrates is a metal film on a film substrate. A metallized region and a marginal part composed of a non-metallized region, the marginal part comprising:
(1) a first margin portion provided on one side in the longitudinal direction of the film base, (2) a plurality of second margin portions extending from the first margin portion at a predetermined interval, and (3) )
A fuse portion formed of a metallized portion is formed by a plurality of third margin portions extending from the second margin portion, and the tips of the third margin portions that are close to each other form a fuse portion that is a metallized portion, and the filling resin is A capacitor with a safety function characterized by a hardness of A50 to A85 at room temperature according to JIS K6301.