JP2006286973A - Capacitor and its manufacturing process - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a capacitor exhibiting high sealability as well as high bonding strength over a long term. <P>SOLUTION: The capacitor 1 comprises a capacitor element 5, an enclosure case 2 having an opening containing the capacitor element 5, a sealing body 3 for hermetically sealing the opening, and a lead-out terminal 4 connected to the capacitor element 5 and led out from the sealing body 3, where the lead-out terminal 4 is bonded to the sealing body 3 under hermetically sealed state, the sealing body 3 is composed of a material that transmits a laser light 20, and the abutting portion of the lead-out terminal 4 and the sealing body 3 is irradiated with laser light 20 and sealed tightly. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention provides a capacitor element, an exterior case having an opening for accommodating the capacitor element, a sealing body that tightly seals the opening, and connected to the capacitor element, and external to the sealing body. The present invention relates to a capacitor including a drawn-out lead terminal, wherein the lead-out terminal is joined to the sealing body in a sealed state, and a method for manufacturing the same.

  As a means for joining the lead terminal and the sealing body in a conventional capacitor, for example, a terminal insertion hole of the lead terminal is formed in a sealing body made of an electrical insulating material such as rubber, and a round bar shape slightly larger than the diameter of the terminal insertion hole is formed. The extraction terminal was inserted into the terminal insertion hole to ensure sealing performance. And what applied the coupling agent to the joint surface in order to improve the sealing performance and pull-out strength is known (for example, refer to patent documents 1). However, this type of joining means has a limitation on the pull-out strength because the terminal is only inserted into the hole even if a coupling agent is applied, and there is a possibility that the sealing performance cannot be maintained for a long time due to deterioration of the sealing body. It was.

  Under the circumstances described above, it is also known that the sealing body is made of a thermoplastic resin and is pressed or heat-sealed to a metal lead terminal to improve sealing performance and bonding strength. (For example, refer to Patent Document 2).

JP-A-6-181149 (paragraphs 0005 and 0029, FIG. 1) JP-A-5-259008 (paragraph 0012)

  Since the joining means described in Patent Document 2 is joining by pressure welding or heat fusion, the sealing property and joining strength between the lead terminal and the sealing body are improved, but the sealing body by heat cycle or long-term use is improved. A decrease in sealing performance and bonding strength due to deterioration cannot be avoided, and there is room for further improvement.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a capacitor having a high sealing performance and a high bonding strength over a long period of time and a method for manufacturing the same.

In order to solve the above-mentioned problem, the capacitor according to claim 1 of the present invention provides:
A capacitor element, an outer case having an opening for accommodating the capacitor element, a sealing body for tightly sealing the opening, and a lead connected to the capacitor element and led out from the sealing body A capacitor in which the extraction terminal is joined to the sealing body, wherein the sealing body is made of a laser light transmitting material, and a contact portion between the extraction terminal and the sealing body is irradiated with laser light. It is characterized by being tightly sealed by.
According to this feature, it is possible to irradiate a laser beam to an arbitrary position of the contact portion and the whole through the transparent material, so that the bonding force does not decrease even with an external force, and for a long time. It is possible to provide a capacitor having a joining structure of an extraction terminal and a sealing body having a large joining force and excellent sealing performance.

A capacitor according to claim 2 of the present invention is the capacitor according to claim 1,
The laser light transmitting material is characterized in that the laser light transmittance is 15% or more.
According to this feature, when the laser beam transmittance of the transparent material is 15% or more, the laser beam can be effectively irradiated onto the contact portion, so that the productivity of the capacitor can be improved and the energy can be saved.

A capacitor according to claim 3 of the present invention is the capacitor according to claim 1 or 2,
The permeable material is a thermoplastic resin or a thermoplastic elastomer.
According to this feature, there are many types of thermoplastic resins or thermoplastic elastomers, and those suitable for permeability or softness can be selected according to the material of the lead terminal. In particular, the thermoplastic elastomer can further increase the degree of adhesion with the lead-out terminal during laser light irradiation due to its elastic force.

A capacitor according to claim 4 of the present invention is the capacitor according to claim 3,
The thermoplastic resin is any one selected from polyetheretherketone, polyphenylene sulfide, or liquid crystal polymer.
According to this feature, any of polyetheretherketone, polyphenylene sulfide, or liquid crystal polymer has excellent adhesion to the lead terminal and a large bonding force.

The method for manufacturing a capacitor according to claim 5 of the present invention is as follows.
A capacitor element, an outer case having an opening for accommodating the capacitor element, a sealing body for tightly sealing the opening, and a lead connected to the capacitor element and led out from the sealing body A capacitor manufacturing method comprising: a terminal, wherein the lead terminal is joined to the sealing body, wherein the sealing body is made of a laser light transmitting material, and the lead terminal is surrounded by the sealing body. The sealing body and the extraction terminal are brought into contact so as to be further derived, and then the laser beam is irradiated to the corresponding contact portion from the sealing body side, and the contact portion of the sealing body with the extraction terminal is melted or softened so that the extraction terminal and the sealing body It is characterized by joining.
According to this feature, the metal material of the extraction terminal is surrounded by the sealing body made of a laser light transmitting material and is irradiated with laser light after contacting the sealing body and the extraction terminal so as to be led out from the sealing body. Since the contact portion with the lead-out terminal of the sealing body is melted or softened and joined, the sealing degree is high, and any portion of the contact portion can be irradiated with the laser light through the transparent material. Sufficient bonding strength can be obtained.

A capacitor manufacturing method according to claim 6 of the present invention is the capacitor manufacturing method according to claim 5,
While the laser beam is irradiated, the contact portion is in a pressed state.
According to this feature, by pressing the contact portion while irradiating the laser beam, the degree of adhesion is increased, and the bonding with a large bonding force can be performed efficiently.

A capacitor manufacturing method according to claim 7 of the present invention is the capacitor manufacturing method according to claim 5 or 6,
The abutting portion is preliminarily bonded by thermal welding or ultrasonic waves before irradiation with laser light.
According to this feature, the alignment of the lead terminal and the sealing body can be omitted at the time of laser light irradiation, which is suitable for continuous production, and the re-melting of the heat welded part or the ultrasonic welded part makes it possible to homogenize the sealed part of both. I can plan.

  Examples of the present invention will be described below.

  An embodiment of the present invention will be described with reference to the drawings. First, FIG. 1 is a partially broken perspective view showing a capacitor in the first embodiment, and FIG. 2 shows the joining of an extraction terminal and a sealing body using a laser beam. It is sectional drawing shown.

  Reference numeral 11 in FIG. 1 denotes a rectangular capacitor 11 to which the present invention is applied. The capacitor 11 includes a bottomed rectangular tube-shaped outer case 12 and two lead terminals 14 housed inside the outer case 12. Is connected to the capacitor element 15 and a substantially rectangular sealing body 13 that seals the opening of the outer case 12 and leads the lead-out terminal 14 to the outside in a sealed state.

  The exterior case 12 is filled with an electrolyte solution, and a plurality of capacitor elements 15 housed in the exterior case 12 are stacked on the front and back via separators that hold the electrolyte solution between the anode foil and the cathode foil. The laminated type electrolytic capacitor element 15 is used. The capacitor element 15 used in this embodiment may be a cylindrical electrolytic capacitor element that is wound between an anode foil and a cathode foil via a separator, or an electric double layer capacitor or a film capacitor. Various capacitors such as these may be used.

The lead terminal 14 is attached to the sealing body 13 with one end of the lead terminal 14 connected to the electrode foil and the other through the sealing body 13. Note that the lead terminal 14 used in this embodiment may be one in which an external terminal for external lead is inserted in the sealing body 13 in advance, and an internal terminal separately connected to the electrode foil is connected to the external terminal. .

  The connection portion of the lead terminal 14 to the capacitor element 15 is formed in a flat plate shape so as to be easily connected to an electrode foil (anode foil and cathode foil), although not particularly shown. The capacitor element 15 is made of aluminum. In this embodiment, since the capacitor element 15 to be used has a square corner shape in plan view, the outer case 12 has a corner shape. However, the present invention is not limited to this, and the capacitor to be used is not limited thereto. If the element 15 is oblong in plan view, the outer case may be a long cylindrical shape. If the capacitor element 15 used is a circular cylindrical shape, the outer case is also cylindrical. The shape of the outer case 12 may be appropriately selected according to the shape of the capacitor element.

  In the present embodiment, the outer case 12 is formed of an absorbent resin having the ability to absorb the laser light 20. The absorbent resin may be a thermoplastic resin, a thermoplastic elastomer, or the like similar to the thermoplastic resin as the permeable material of the sealing plate 12 to be described later. However, the heat resistance and chemical resistance during normal use of the capacitor can be used. Polypropylene and polyphenylene sulfide having excellent properties are suitable. A contact surface 12 a having a predetermined width substantially the same as the thickness of the outer case 12 is formed at the upper end of the opening of the outer case 12. The abutting surface 12 a is abutted against the lower surface 13 a of the sealing body 13.

  Further, the lead terminal 14 shown in FIG. 1 is formed using a metal material such as aluminum. In addition, an aluminum alloy, iron, copper, tin, or the like can be used as the metal material used for the lead terminal 14. Metal plating for soldering may be applied to the surface of the part drawn out from the sealing body of the lead terminal.

Next, the laser beam 20 used for bonding the sealing body 13 and the lead terminal 14 in this embodiment will be described in detail. The laser used in this embodiment may be a semiconductor laser, a YAG laser, or a CO ₂ laser. preferable. Further, the optimum laser beam 20 may be configured by changing various laser irradiation conditions depending on the metal material or the like of the lead terminal 4.

  Next, the sealing body 13 will be described in detail. The sealing body 13 shown in FIG. 2 is formed of a thermoplastic resin as a transmissive material in the present embodiment having the transmittance of the laser beam 20. In addition to the thermoplastic resin, a thermoplastic elastomer (TPE) or the like may be used as a permeable material. There are many types of thermoplastic resins and thermoplastic elastomers, and metal materials constituting the lead terminal 14 (this embodiment) In the example, a material suitable for permeability and softness can be selected according to aluminum). In particular, the thermoplastic elastomer can further increase the degree of adhesion with the extraction terminal 14 when irradiated with laser light due to its elastic force. This thermoplastic elastomer is a material that has rubber elasticity at room temperature and is plasticized at high temperatures and can be melt-molded. Styrene, olefin, polyvinyl chloride, polyurethane, polyester, polyamide, fluorine , Chlorinated polyethylene, nitrile, silicone, 1,2 polybutadiene, trans-1,4 polyisoprene, chlorinated ethylene copolymer cross-linked alloy, etc. can be used, and polyester elastomer and polyolefin elastomer are particularly suitable. Used for.

  When a thermoplastic resin is used, polyether ether ketone (PEEK), polyphenylene sulfide (PPS), liquid crystal polymer (LCP), polypropylene, polyethylene, polyethylene terephthalate, polybutylene terephthalate, polyvinyl chloride, fluororesin, Acrylic or the like is used. In particular, PEEK, PPS, and LCP are all excellent in sealing performance against metal materials and have high bonding strength, and are excellent in heat resistance and chemical resistance during normal use and are suitable for use in capacitors. As the liquid crystal polymer (LCP), wholly aromatic polyamide, wholly aromatic polyester, polyester amide, polyamide imide, polyester carbonate, and polyazomethine are preferably used.

  In addition, you may add additives, such as reinforcing fibers, such as glass fiber and carbon fiber, fillers, such as inorganic substance powder, and a coloring material, to these permeable materials mentioned above. However, the content of the additive in the transmissive material is adjusted so that the transmittance of the laser beam 20 is maintained at 15% or more at least in the region irradiated with the laser at the time of laser irradiation described later. Is done.

  As shown in FIG. 2, two through holes 13 b (contact portions) are formed in the central portion of the sealing body 13, and the two lead terminals 14 connected to the capacitor element 15 penetrate through the through holes 13 b. By doing so, the capacitor element 15 is attached to the sealing body 13. The outer peripheral surface (outer diameter) of the lead terminal 14 is formed to be slightly larger than the inner peripheral surface (inner diameter) of the through hole 13b, and the lead terminal 14 is tightly fitted into the through hole 13b. Therefore, when the extraction terminal 14 is attached to the through hole 13b of the sealing body 13, the contact portion 14a of the extraction terminal 14 with the sealing body 13 is pressed.

  In this embodiment, all of the sealing body 13 is formed of a permeable material. However, the present invention is not limited to this, and the permeable region of the sealing body 13 formed of a permeable material is as follows. It is only necessary to be formed in the vicinity of the through hole 13b of the sealing body 13 that is in contact with at least the region irradiated with the laser, that is, the contact portion 14a of the so-called lead terminal 14.

  Next, the joining operation of the sealing body 13 and the extraction terminal 14 using the laser beam 20 will be described. As shown in FIG. 2, the vicinity of the extraction terminal 14 including the planned joining portion of the contact portion 14a is heated by a heating means such as a heater. By heating, the contact portion 14a of the lead terminal 14 and the through hole 13b of the sealing body 13 are preliminarily bonded in advance by heat welding.

  Then, as shown in FIG. 2, the laser beam 20 is irradiated from above the sealing body 13 toward the contact portion 14 a of the extraction terminal 14 from an oblique direction. The laser beam 20 passes through the sealing body 13 formed of a transmissive material and is irradiated to the contact portion 14 a of the lead terminal 14. Then, the temperature of the contact portion 14a is increased by the energy of the laser beam 20, and the heat of the contact portion 14a is conducted to the inner peripheral surface of the through hole 13b of the sealing body 13 that is in contact with the contact portion 14a. The And the temperature of the internal peripheral surface of the through-hole 13b of the sealing body 13 rises, and the internal peripheral surface of the through-hole 13b of the sealing body 13 can be softened or melted. In addition, by continuing the heating in the vicinity of the contact portion 14a even during the laser irradiation, the temperature rise of the planned joining portion can be accelerated. The surface of the contact portion 14a of the lead terminal 14 made of aluminum is not softened or melted even when the laser beam 20 is irradiated.

  When the irradiation region of the laser beam 20 is gradually moved along the outer peripheral surface of the contact portion 14a of the extraction terminal 14, the region corresponding to the contact portion 14a of the extraction terminal 14 that has already been irradiated with the laser beam 20 is detected. The inner peripheral surface of the through-hole 13b of the sealing body 13 begins to solidify, and the through-hole 13b of the sealing body 13 is firmly joined to the contact portion 14a of the lead terminal 14. Such laser irradiation is performed over the entire outer peripheral surface of the contact portion 14 a of the lead terminal 14, and the contact portion 14 a is surface-bonded to the through hole 13 b of the sealing body 13. In addition, if the laser beam transmittance of the above-described transmissive material is 15% or more, the laser beam 20 can be effectively applied to the contact portion 14a, so that the productivity of the capacitor 11 can be improved and energy can be saved. .

  Further, the extraction terminal 14 is tightly fitted into the through hole 13b, and the abutting portion 14a of the extraction terminal 14 with the sealing body 13 is in a pressed state. The close contact between the contact portion 14a of the terminal 14 and the through-hole 13b of the sealing body 13 is increased, and it is possible to efficiently join with high joining strength.

  In addition, in order to make the contact part 14a with the sealing body 13 of the extraction terminal 14 into a press state, a protrusion is provided in the inner peripheral surface of the through-hole 13b of the sealing body 13, and this protrusion is used as the outer peripheral surface of the extraction terminal 14. (Outer diameter) The inner peripheral surface (inner diameter) of the through-hole 13b may be formed small by providing the entire outer diameter. Further, a protrusion may be formed on the entire outer peripheral surface of the lead terminal 14 so that the outer peripheral surface (outer diameter) of the lead terminal 14 is increased. Furthermore, by forming a tapered surface that guides the lead terminal 14 at the end of the through hole 13b on the capacitor element 15 side of the through hole 13b of the sealing body 13, the lead terminal 14 can be easily penetrated into the through hole 13b and the through hole 13b is penetrated. The contact portion 14a of the lead terminal 14 and the through hole 13b of the sealing body 13 may be pressed later.

  In this embodiment, before the laser beam 20 is irradiated, heat is applied by a heater or the like in the vicinity including the planned joining portion of the abutting portion 14a of the lead terminal 14, and by heat welding with the through hole 13b of the sealing body 13. Temporary joining is performed, so that the alignment of the lead-out terminal 14 and the sealing body 13 can be omitted at the time of irradiation with the laser beam 20, and the temperature of the contact surface 14a can be accelerated, which is suitable for continuous production and a heat welded portion. By remelting, the sealing part of both can be homogenized. In the present embodiment, the through hole 13b of the sealing body 13 and the contact portion 14a of the lead terminal 14 are temporarily joined by using heat welding. However, ultrasonic welding or the like is used in addition to heat welding. Thus, the through hole 13b of the sealing body 13 and the contact portion 14a of the lead terminal 14 may be temporarily joined.

  And the exterior case 12 and the sealing body 13 are joined by the method similar to joining of the extraction terminal 14 and the sealing body 13. That is, as shown in FIG. 2B, the laser beam 20 ′ that has passed through the sealing body 13 is irradiated with the laser beam 20 ′ on the edge of the sealing body 13 so that the exterior is made of a thermoplastic resin as an absorbent material. The contact surface 12a of the case 12 is irradiated and the temperature of the contact surface 12a rises to soften or melt. The heat of the contact surface 12a is conducted to the edge of the lower surface 13a of the sealing body 13 that is in contact with the contact surface 12a, the temperature of the edge of the lower surface 13a of the sealing body 13 rises, and the sealing body 13 By softening or melting the edge of the lower surface 13a, it is possible to firmly bond together the melting of both the edge of the lower surface 13a of the sealing body 13 and the contact surface 12a of the exterior case 12. It should be noted that, for example, polypropylene is used as the absorbent material constituting the sealing body 13, and polypropylene is used as the permeable material constituting the exterior case 12. Is obtained.

  In the first embodiment, the outer casing 12 is made of a thermoplastic resin as a laser light absorbing material. However, the present invention is not limited to this, and the laser light absorbing material may be a metal material such as aluminum or aluminum alloy. it can. Since the capacitor element 15 accommodated in the outer case 12 is mainly formed of aluminum, the outer case 12 is formed of aluminum, thereby preventing corrosion due to the battery forming action and adversely affecting the electric characteristics of the capacitor. There is nothing.

  According to the joining structure of the lead terminal 14 and the sealing body 13 in the capacitor 11 of the present invention, the entire contact portion 14a of the lead terminal 14 can be irradiated with the laser beam 20 through the sealing body 13 that is a transmissive material. Therefore, it is possible to provide the capacitor 11 having a joining structure of the extraction terminal 14 and the sealing body 13 that does not decrease the joining force with respect to an external force and has a large joining force over a long period of time and excellent in sealing performance.

  Further, since the lead terminal 14 and the sealing body 13 are firmly joined, and the outer case 12 and the sealing body 13 are also firmly joined, the sealing performance inside the capacitor 11 is improved. In other words, the influence on the capacitor element 15 from the outside is more strongly protected, so that moisture, foreign matter, and the like do not enter the capacitor 11 from the outside, and the electrolyte solution and its vaporized components inside the capacitor 11 are prevented. Leakage is also reliably prevented. Further, since any portion of the contact portion 14a of the lead terminal 14 can be irradiated with the laser light 20 through the sealing body 13 made of a transmissive material, a sufficient bonding force can be obtained.

  Next, a second embodiment of the present invention will be described with reference to FIGS. 3 is a partially broken perspective view showing the capacitor in Example 1, FIG. 4A is an exploded sectional view of the capacitor element, the outer case, and the sealing body, and FIG. 4B is a laser beam. It is sectional drawing which shows joining of the lead-out terminal and sealing body using this.

  As shown in FIG. 3, the cylindrical capacitor 1 according to the second embodiment includes a bottomed cylindrical outer case 2 and a capacitor element 5 to which two lead terminals 4 housed inside the outer case 2 are connected. It is composed of a substantially disc-shaped sealing body 3 formed with a through hole 3b (contact portion) for sealing the opening of the outer case 2 and leading the lead terminal 4 to the outside in a sealed state. In this embodiment, a wound laminated type electrolytic capacitor in which the capacitor element 5 is wound between an anode foil and a cathode foil via a separator is used.

  As shown in FIG. 4A, the lead terminal 4 is made of aluminum. Further, the sealing body 3 in Example 2 is formed of a thermoplastic resin as a transmissive material, and the outer case 2 is formed of a metal material such as aluminum as an absorptive material having an absorptivity of the laser beam 20. . As this absorbent resin, the same thermoplastic resin or thermoplastic elastomer as the permeable material of the sealing plate 12 described in Example 1 can be used. Examples of the thermoplastic material include polypropylene, Polyphenylene sulfide is preferred. In addition, a black colorant such as carbon black is added to the absorptive resin to facilitate absorption of the laser beam 20.

  As shown in FIG. 4B, when joining the lead terminal 4 and the sealing body 3, first, pressure from the left and right side surfaces of the sealing body 3 toward the center of the sealing body 3 is applied by a pressing means (not shown). Add. Then, the contact portion 4a of the lead terminal 4 and the through hole 3b of the sealing body 3 are pressed. Then, the laser beam 20 is irradiated from above the sealing body 3 toward the abutting portion 4 a that abuts the through hole 3 b of the sealing body 3 in the lead-out terminal 4 from an oblique direction.

  The laser beam 20 passes through the sealing body 3 formed of a transmissive material and is irradiated to the contact portion 4 a of the lead terminal 4. And the temperature of the contact part 4a rises, the heat | fever is conducted by the internal peripheral surface of the through-hole 3b of the sealing body 3, and the temperature of the internal peripheral surface of the through-hole 3b of the sealing body 3 rises, A sealing body 3 is softened or melted, and the contact portion 4a of the lead terminal 4 and the inner peripheral surface of the through hole 3b of the sealing body 3 are joined.

  And the exterior case 2 and the sealing body 3 are joined by the method similar to joining of the extraction terminal 4 and the sealing body 3. That is, as shown in FIG. 4B, when the laser light 20 ′ is irradiated from above the sealing body 3, the laser light 20 ′ that has passed through the sealing body 3 is brought into contact with the lower surface 3 a of the sealing body 3. The contact surface 2d is irradiated and the temperature of the contact surface 2d is increased. The heat of the contact surface 2d is transmitted to the lower surface 3a of the sealing body 3 in contact with the contact surface 2d, the temperature of the edge of the sealing body 3 rises, and the lower surface 3a of the sealing body softens or melts. Thereby, the lower surface 3a of the sealing body 3 and the contact surface 2d of the exterior case 2 can be firmly joined.

  Next, a third embodiment of the present invention will be described with reference to FIGS. FIG. 5 is a partially broken perspective view showing the capacitor in Example 3, and FIG. 6A is a cross-sectional view showing joining of the lead-out terminal and the transmissive film using laser light, and FIG. ) Is a cross-sectional view showing a capacitor using a laminate film.

  As shown in FIG. 5, in the laminated capacitor 21 in Example 3, a capacitor element 25 to which two lead terminals 24 are connected is wrapped with a laminate film 22. In this embodiment, a multilayer electrolytic capacitor is used in which a plurality of capacitor elements 25 are laminated between the anode foil and the cathode foil via a separator. However, a separator is used between the anode foil and the cathode foil. Alternatively, a cylindrical electrolytic capacitor using a cylindrical capacitor element wound therethrough may be used.

  Further, the laminate film 22 constitutes the outer case of the present invention, so that the capacitor 21 can be thinned and can cope with any shape of the capacitor element 25. The laminate film 22 is a composite film material in which an insulating resin layer made of nylon, polyethylene terephthalate, polybutylene terephthalate, polyphenylene sulfide, or polyimide is formed on both surfaces of a metal material such as aluminum.

  As shown in FIG. 5, the lead terminal 24 is made of aluminum, and a permeable film as a sealing body in this embodiment is wound so as to surround a part of the lead terminal 24. Furthermore, the permeable film is formed of the permeable material described in Example 1. The laminate film 22 has a cylindrical shape with an upper end and a lower end opened. After the capacitor element 25 is surrounded, the upper end and the lower end of the laminate film 22 are sealed to seal the inside. .

  Referring to FIG. 6 (a), the joining of the lead terminal 24 and the permeable film 23 will be described. First, the permeable film 23 is sandwiched from both sides by a pressing means (not shown), and further, by a heating means (not shown). Heat is applied to the permeable film 23. Then, the transparent films 23 are heat-welded. Furthermore, when the permeable film 23 is heat-welded, the permeable film 23 is formed with a through hole 23a (contact portion) for leading the lead terminal 24 to the outside.

  When the permeable film 23 shown in FIG. 6A is sealed by heat welding, the permeable films 23 are firmly joined to each other because they are formed of a thermoplastic resin. Moreover, although the through-hole 23a of the permeable film 23 and the contact part 24a of the extraction terminal 24 contact | abutted by this through-hole 23a are also joined by heat welding, the permeable film 23 and the extraction terminal 24 are mutually different materials. Since the thermal expansion coefficients of these materials (resin and aluminum) are different, the contact between the through hole 23a of the transparent film 23 and the lead terminal 24 can be achieved by using the laminated capacitor 21 for many years. The joint with the part 24a may be peeled off. Therefore, in order to ensure the bonding between the through hole 23a of the transparent film 23 and the contact portion 24a of the extraction terminal 24, the bonding operation of the transmission film 23 and the extraction terminal 4 using the laser beam 20 is performed.

  Next, the joining operation of the transparent film 23 and the extraction terminal 24 using the laser beam 20 will be described. As shown in FIG. 6A, the laser beam 20 is applied to the extraction terminal 24 from the side of the transmission film 23. Irradiate toward the contact portion 24a. The laser beam 20 is transmitted through a transmissive film 23 formed of a transmissive material, and is applied to the contact portion 24 a of the lead terminal 24. And the temperature of the contact part 24a rises, the heat is conducted to the inner peripheral surface of the through hole 22a of the permeable film 23, and the temperature of the inner peripheral surface of the through hole 22a of the permeable film 23 rises. The inner peripheral surface of the through hole 22a of the transmissive film 23 is melted, and the contact portion 24a of the lead terminal 24 and the inner peripheral surface of the through hole 22a of the laminate film 23 are joined.

  Then, the upper and lower ends of the laminate film 22 shown in FIG. 6B are sandwiched from both sides by pressing means (not shown), and heat is further applied to the upper and lower ends of the laminate film 22 by heating means (not shown). Then, the upper end of the laminate film 22 is joined so as to sandwich the transparent film 23 wound around the lead terminal 24, and the laminate film 22 and the transparent film 23 are thermally welded, and the lower ends of the laminate film 22 are also thermally welded. Then, the inside of the laminate film 22 is sealed. In this embodiment, by using heat welding, the upper end of the laminate film 22 and the transmissive film 23 are joined together, and the lower ends of the laminate film 22 are joined together, but the laminate film 22 is used using an adhesive or the like. The upper and lower ends may be joined.

  According to the joining structure of the lead terminal 24 and the transmissive film 23 in the capacitor 21 of the present invention, the transmissive film 23 is locally heated using the laser beam 20, so that the transmissive film 23 made of resin is completely formed. It is possible to heat to a temperature at which it melts. When the transmissive film 23 melted by the laser beam 20 is solidified, it is strongly bonded to the surface of the lead terminal 24 made of aluminum. Since the laser beam 20 can be applied to the entire contact portion 24a of the extraction terminal 24 through the transmissive film 23, the entire bonding area between the transmissive film 23 and the extraction terminal 24 can be firmly bonded, and external force can be increased. In contrast, it is possible to provide the capacitor 21 whose bonding force does not decrease.

  From the description of each of the above embodiments, the joining structure of the lead terminals 4, 14, 24 and the sealing bodies 3, 13 (transparent film 23) and the joining method in the capacitor according to the present invention are complicated to the capacitors 1, 11, 21. Therefore, the capacitors 1, 11, and 21 can be miniaturized and the lead terminals 4, 14, 24 and the sealing bodies 3, 13 (and the sealing bodies 3, 13 ( The manufacturing method of the capacitors 1, 11 and 21 can maintain the bonding strength of the permeable film 23), has a high bonding strength over a long period of time, and has high sealing performance.

  Although the embodiments of the present invention have been described with reference to the drawings, the specific configuration is not limited to these embodiments, and modifications and additions within the scope of the present invention are included in the present invention. It is.

  For example, in Example 3, a laminate film having a cylindrical shape with an open upper end and a lower end was used. However, the present invention is not limited to this, and the outer peripheral portion is joined using two laminate films, and the laminate film is disposed at the lead terminal. The transparent film may be bonded with a laser beam, and the optimum shape of the laminate film is used according to the outer shape of the capacitor.

  Further, in Example 1 and Example 2, a sealing method using a laser was used to seal the sealing body made of a laser light-transmitting material and the outer case. However, the sealing is not limited to this, and the sealing body and the outer case are sealed. It is also possible to use heat welding (hot press), adhesive, ultrasonic bonding, or the like.

  In the first and second embodiments, the lead terminal drawn out from the sealing body has a linear shape. However, the present invention is not limited to this, and the sealing body is not limited to this direction in the direction of separating the cathode side and the anode side lead terminals. It can be bent along the surface, used as a chip product, and adapted to surface mounting.

3 is a partially broken perspective view showing the capacitor in Example 1. FIG. It is sectional drawing which shows joining of the extraction terminal and sealing body using a laser beam. 10 is a partially broken perspective view showing a capacitor in Example 2. FIG. (A) is an exploded assembly sectional view of a capacitor element, an exterior case, and a sealing body, and (b) is a sectional view showing joining of a lead terminal and a sealing body using a laser beam. 10 is a partially broken perspective view showing a capacitor in Example 3. FIG. (A) is sectional drawing which shows joining of the lead-out terminal and transparent film using a laser beam, (b) is sectional drawing which shows the capacitor | condenser using a laminate film.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cylindrical capacitor 2 Exterior case 2a Contact surface 3 Sealing body 3a Lower surface 3b Through-hole 4 Lead-out terminal 4a Contact part 5 Capacitor element 11 Square capacitor 12 Exterior case 12a Contact surface 13 Sealing body 13a Lower surface 13b Through-hole 14 Terminal 14a Contact portion 15 Capacitor element 20 Laser light 21 Laminated capacitor 22 Laminate film 23 Transparent film 23a Through hole 24 Lead-out terminal 24a Contact portion 25 Capacitor element

Claims (7)

  A capacitor element, an outer case having an opening for accommodating the capacitor element, a sealing body for tightly sealing the opening, and a lead connected to the capacitor element and led out from the sealing body A capacitor in which the extraction terminal is joined to the sealing body, wherein the sealing body is made of a laser light transmitting material, and a contact portion between the extraction terminal and the sealing body is irradiated with laser light. A capacitor characterized in that it is tightly sealed.   The capacitor according to claim 1, wherein the laser light transmitting material has a laser light transmittance of 15% or more.   The capacitor according to claim 1, wherein the permeable material is a thermoplastic resin or a thermoplastic elastomer.   The capacitor according to claim 3, wherein the thermoplastic resin is any one selected from polyether ether ketone, polyphenylene sulfide, and a liquid crystal polymer.   A capacitor element, an outer case having an opening for accommodating the capacitor element, a sealing body for tightly sealing the opening, and a lead connected to the capacitor element and led out from the sealing body A capacitor comprising: a terminal, wherein the lead terminal is joined to the sealing body, wherein the sealing body is made of a laser transmissive material, and the lead terminal is surrounded by the sealing body. The sealing body and the extraction terminal are brought into contact so as to be further derived, and then the laser beam is irradiated to the corresponding contact portion from the sealing body side, and the contact portion of the sealing body with the extraction terminal is melted or softened so that the extraction terminal and the sealing body And a capacitor manufacturing method.   The method for manufacturing a capacitor according to claim 5, wherein the abutting portion is in a pressed state while the laser beam is irradiated.   The method of manufacturing a capacitor according to claim 5, wherein the contact portion is preliminarily bonded by thermal welding or ultrasonic waves before irradiation with laser light.

Images