JP2005183753A - Pressure relief valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To effectively prevent intrusion of dust and ejection of contents such as an electrolyte in a pressure relief valve 11 being installed to a sealing plate 4 for a pressure vessel such as a capacitor while releasing a pressure by a releasing when the pressure in the pressure vessel exceeds a specified value. <P>SOLUTION: A sub-lip 21 preventing the intrusion of dust and the ejection of the contents is formed on the atmospheric air side of a main lip 15 as the valve body of the pressure relief valve 11. It is preferable that a communication path 25 releasing a space C between the main lip 15 and the sub-lip 21 to atmospheric air is formed to the sub-lip 21 so that a pressure difference is not generated inside and outside the sub-lip 21. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a pressure release valve which is provided on a sealing plate of a pressure vessel such as a capacitor or a capacitor and opens when the sealing pressure in the pressure vessel exceeds a predetermined valve opening pressure to release the pressure. is there.

  In a sealed aluminum electrolytic capacitor, an electric double layer capacitor, or the like, the opening of a pressure vessel that houses the element body is closed by a sealing plate that is sealed via a gasket. If such a completely sealed structure is used, when a sudden load is applied, the internal pressure of the container increases due to Joule heat generation, which may cause a decrease in the function and lifetime of the capacitor. For this reason, conventionally, the bottom of the pressure vessel is cut into a rupture plate, or the pressure vessel is prevented from rupturing by attaching a rubber cap to the lid as a safety valve, or the sealing plate For example, by applying a water repellent treatment to a porous membrane made of PTFE or the like, a gas that permeates the gas but does not permeate the liquid and is attached with a breather that releases the internal pressure of the container to the outside. The one that can release the pressure of the is being developed.

  According to the prior art, when a rupturable plate or a safety valve is used as the sealing plate, once the container is ruptured, it cannot be used thereafter, and therefore cannot be used repeatedly.

  In addition, the breather provided on the sealing plate has a function of keeping the internal pressure of the pressure vessel constant and preventing leakage of the encapsulated liquid such as an electrolyte, but even with heat and internal pressure generated in a normal use state, Since the gas in the container is slightly released from the breather, the electrolytic solution is likely to be reduced by evaporation, and water vapor from outside tends to enter. Further, in a poor environment, the breather porous membrane may be clogged, making it difficult to expect stable performance. Also, since the breather cannot cope with a sudden increase in internal pressure, it is necessary to provide an explosion-proof valve to release the internal pressure instantly and prevent the container from exploding when the internal pressure exceeds a predetermined value. there were.

  Therefore, the oil seal type pressure release valve 51 of FIG. 6 previously proposed by the applicant of the present application has a configuration in which only one lip seal 54 is assembled to the sealing plate 52 provided with the valve mounting space 53. A valve device that is easy to assemble and has high operational reliability (see Patent Document 1).

  However, since the pressure release valve 51 is disposed in the valve mounting space 53 opened on the upper surface (the container exterior A side) of the sealing plate 52 as shown in the figure, it is used in a situation where it is exposed to the external environment. become. Further, since the capacitor or capacitor to which the pressure release valve 51 is attached is often installed in a direction (vertical or oblique) with the valve mounting space 53 on the upper side, dust in the atmosphere is placed on the pressure release valve 51. There is a possibility of deposition and adhesion. When these dusts enter the lip portion 55 that functions as a valve body, the valve opening characteristics are impaired, and a gap is generated between the lip portion 55 and the shaft portion 56 due to the accumulated dust. There is a risk that the internal electrolyte may leak or steam.

  Further, since the lip portion 55 is opened to the outside, the electrolytic solution adhering to the vicinity of the lip portion 55 is ejected to the outside with the release of the internally generated gas when the valve is opened, and the vicinity of the pressure release valve 51. Furthermore, there is a possibility that the electrolytic solution adheres to the substrate or the bus bar, causing circuit corrosion or short circuit.

International Publication No. WO03 / 044397A1 Pamphlet

  In view of the above points, the present invention can effectively suppress the intrusion of dust or the ejection of internal contents such as an electrolyte, and the above prior art can be further improved from these points. An object is to provide a pressure relief valve that can be used.

In order to achieve the above object, a pressure release valve according to claim 1 of the present invention is provided on a sealing plate of a pressure vessel and opens when the pressure in the pressure vessel exceeds a predetermined value to release the pressure. The pressure release valve is characterized in that a sub lip portion is provided on the atmosphere side of the main lip portion forming the valve body of the pressure release valve to prevent the intrusion of dust and the ejection of internal contents.
The pressure relief valve according to claim 2 of the present invention is characterized in that in the pressure relief valve according to claim 1, a communication passage is provided to open the space between the main lip portion and the sub lip portion to the atmosphere. It is.
The pressure relief valve according to claim 3 of the present invention is the pressure relief valve according to claim 2 described above, wherein the communication passage is formed by a hole provided in the reinforcing ring of the sub lip portion. .

The pressure relief valve according to claim 4 of the present invention is the pressure relief valve according to claim 2 described above, wherein the communication passage is formed by a recess provided at the lip end of the sub lip portion.
The pressure relief valve according to claim 5 of the present invention is the pressure relief valve according to claim 2 described above, wherein the communication path is formed by a convex portion provided at the lip end of the sub lip portion contacting the mating seal surface. It consists of a gap portion formed between the sub lip portion and the mating seal surface.
Furthermore, a pressure relief valve according to a sixth aspect of the present invention is the pressure relief valve according to any one of the first to fifth aspects, wherein the reinforcing ring of the sub lip portion is fitted to the reinforcing ring of the main lip portion. Thus, both lip portions are integrated.

  As in the pressure release valve according to the first aspect of the present invention having the above-described configuration, when a sub lip portion is provided on the atmosphere side of the main lip portion forming the valve body to prevent dust intrusion and internal contents from being ejected, Due to the sealing action of the sub lip portion, it is possible to suppress the entry of external dust or the ejection of the internal contents during the valve opening operation of the main lip portion.

  However, depending on the shape of the sub lip, the space between the main lip and the sub lip may be sealed when the main lip is closed. If this occurs, the valve opening characteristics of the main lip portion may be impaired. Therefore, it is desirable that this space be communicated with the external environment without being sealed. Therefore, from this point of view, the pressure relief valve according to claim 2 of the present invention is provided with a communication passage that opens the space between the main lip portion and the sub lip portion to the atmosphere, thereby communicating the external environment with this space. It was to be.

The following three types of communication paths are preferable, but in any case, it is preferable to form the communication path as small as possible so as not to impair the sealing action by the sub lip portion.
(1) When the sub lip has a reinforcing ring, a hole is provided in the reinforcing ring, and this hole serves as a communication path.
(2) A concave portion is provided at the lip end of the auxiliary lip portion, and this concave portion serves as a communication path.
(3) Since a convex portion is provided at the lip end of the auxiliary lip portion, and the convex portion abuts against the mating seal surface, the sub lip portion is slightly lifted, and at this time, it is formed between the sub lip portion and the mating seal surface. The gap portion is a communication path (claim 5).

  The secondary lip can be attached directly to the sealing plate as a separate body from the pressure relief valve with the main lip. It is advantageous to integrate it with the valve. Therefore, from this point of view, in the pressure relief valve according to claim 6 of the present invention, the lip portions are integrated by fitting the reinforcing ring of the sub lip portion with the reinforcing ring of the main lip portion.

  The present invention has the following effects.

  That is, first, in the pressure relief valve according to the first aspect of the present invention having the above-described configuration, it is possible to suppress the entry of external dust by the sealing action by the sub lip portion. Therefore, it is possible to prevent the valve opening characteristics from being damaged or leakage from occurring due to dust intrusion. Further, since it is possible to suppress the ejection of the internal contents during the valve opening operation of the main lip portion, it is possible to prevent the occurrence of circuit corrosion, short circuit, etc. due to the ejection of the internal contents. be able to.

  In addition, in the pressure relief valve according to claims 2 to 5 of the present invention, it is possible to prevent the occurrence of a differential pressure between the space between the main lip portion and the sub lip portion and the external environment. It is. Accordingly, it is possible to prevent the valve opening characteristics of the main lip portion from being impaired by this differential pressure.

  In the pressure relief valve according to claim 6 of the present invention, since both the main lip portion and the sub lip portion are integrated, even if the sub lip portion is provided, the number of mounting steps is increased and handling is difficult. There is no complication.

The present invention includes the following embodiments.
(1) In a pressure release valve (one-way valve) used in a capacitor or a capacitor, a dust lip is disposed on the upper part of a main lip that releases internal pressure.
(2) In a pressure relief valve (one-way valve) used in a capacitor or a capacitor, a dust lip is provided at the upper part of the contact portion between the main lip and the shaft.
(3) A through hole, a through groove or a protrusion is provided in the dust lip portion, and atmospheric pressure is introduced into the space between the main lip and the dust lip.

  Next, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows a sealed battery or capacitor (hereinafter simply referred to as a capacitor) 1 which is a pressure vessel having a pressure release valve (also referred to as a one-way valve) according to an embodiment of the present invention. ) Is a longitudinal sectional view thereof, and FIG. 5B is a plan view of FIG. FIG. 2 is an enlarged sectional view taken along line AA in FIG. 1 (B) and shows a half sectional view of the pressure release valve 11.

  The capacitor 1 shown in FIG. 1 is configured as follows.

  That is, first, a bottomed cylindrical case 2 is provided as a pressure vessel made of a metal material such as aluminum. A main body element 3 is accommodated in the case 2, and an upper end opening of the case 2 is It is closed by a disc-shaped sealing plate 4 made of a polymer material such as phenol resin having electrical insulation. The main body element 3 is impregnated with an electrolyte solution enclosed in the case 2. The outer periphery of the case 2 is covered with an outer can 5.

  The sealing plate 4 has an outer peripheral portion continuously formed in the circumferential direction on the case 2 and a caulking portion 2a formed so that the upper end portion of the case 2 is folded back inward. Between the throttle part 2b, it is airtightly fixed via an annular gasket 6 made of a rubber-like elastic material. The sealing plate 4 is provided with a pair of electrode terminals 8 connected to the main body element 3 via lead wires 7 in the thickness direction and a pressure release valve 11. Each of the electrode terminals 8 is integrated in a state where a part thereof is embedded in the sealing plate 4 by insert molding, and is prevented from being detached from the sealing plate 4 by an annular flange 8a formed on the outer peripheral surface thereof. ing.

(1) Sealing plate The sealing plate 4 is formed into a plate shape by a polymer material, for example, a disk shape, an elliptical shape, or a substantially square shape, and the sealing plate 4 is made of aluminum or the like. The electrode terminal 8 is embedded so as to penetrate in the thickness direction, and an external terminal (not shown) made of a metal plate such as SPCC, nickel, stainless steel or the like is attached to the outer end surface of the electrode terminal 8.

  As the molding material of the sealing plate 4 made of a polymer material, a resin material, an elastomer (rubber, thermoplastic elastomer, a mixture of a resin material and rubber, or an elastic body such as a block copolymer or a graft copolymer), a resin material, An elastomer laminate material or the like is used.

  Resin materials include polyolefin resin, polyolefin resin polymerized by metallocene catalyst, polyphenylene sulfide, syndiotactic polystyrene, polyamide resin, polyester resin, polyimide resin, polyamideimide resin, liquid crystalline resin, etc. Examples include thermosetting resins such as plastic resins, phenolic resins, epoxy resins, and imide resins, and fibrous fillers such as glass fibers, carbon fibers, or whiskers, and particulate fillers such as carbon particles, mica, and glass beads. Fillers / reinforcing materials such as agents, metal oxides or processing aids are appropriately blended.

  Examples of elastomers include rubber materials such as butyl rubber, halogenated butyl rubber, vinyl-modified butyl rubber, ethylene propylene rubber, fluorine rubber, acrylic rubber, hydrogenated nitrile rubber and the like, cross-linking agents, fillers, A plasticizer or an antioxidant is appropriately blended. Examples of thermoplastic elastomers include olefin-based thermoplastic elastomers, ester-based thermoplastic elastomers, amide-based thermoplastic elastomers, hydrogenated styrene / butadiene block copolymers, and hydrogenated styrene / isoprene block copolymers. It is produced by a polymerization method, a graft copolymerization method, a dynamic crosslinking method, or the like, and a crosslinking agent, a plasticizer, an antiaging agent or a filler is appropriately blended. Examples of the elastomer such as a mixture of a resin material and rubber, a block copolymer, or a graft copolymer include a mixture of a phenol resin and a hydrogenated nitrile rubber, a phenol resin and an acrylic rubber, a butyl rubber, a fluorine rubber, or the like.

  The polymer material is appropriately selected according to required heat resistance. In this example, an example using a phenol resin which is one of thermosetting resins in terms of heat resistance and cost is shown.

  In this embodiment, the sealing plate 4 and the electrode terminal 8 are integrated by insert molding. However, the present invention is not limited to this, and the sealing plate 4 and the electrode terminal 8 are formed separately, and the sealing plate 4 is molded. A sealing plate of a type in which the electrode terminal 8 is integrated later may be used.

(2) Pressure release valve The pressure release valve 11 is in a closed state because the internal pressure is equal to or lower than the set valve opening pressure in normal use, and the pressure in the capacitor 1 exceeds a predetermined value. The valve is opened to release this pressure, and is configured as follows.

  That is, as shown in FIG. 2, the sealing plate (housing) 4 is provided with a planar circular through-hole penetrating in the thickness direction thereof, and this through-hole serves as a valve mounting space 12. A shaft portion (shaft) 13 is provided in the center of the 12 planes. This shaft portion 13 is arranged with its central axis 0 facing the thickness direction of the sealing plate 4 and is formed integrally or separately from the sealing plate 4, and its outer peripheral surface 13 a is formed by the pressure release valve 11. It functions as a valve seat surface for the main lip portion 15 forming the valve body, and functions as a mating seal surface for the sub lip portion 21 forming the dust seal.

  A main lip portion 15 is press-fitted into the valve mounting space 12 from above, that is, from the container exterior A side. In this embodiment, the main lip portion 15 has an elastic body 18 made of a rubber-like elastic material on a reinforcing ring 17. The lip seal member 16 is vulcanized and bonded. An inward flange portion 14 for positioning the main lip portion 15 is provided at a lower portion of the inner peripheral surface 12a of the valve mounting space 12, that is, at an end portion on the container inside B side. The reinforcing ring 17 is formed by integrally molding a flange portion 17b toward the inside in the radial direction at one end of a cylindrical portion 17a fitted to the inner peripheral surface 12a of the valve mounting space 12. The elastic body 18 is attached to the outer peripheral surface of the cylindrical portion 17a of the reinforcing ring 17 and is attached to the outer peripheral seal portion 18a that seals between the main lip portion 15 and the sealing plate 4, and the inner peripheral surface of the cylindrical portion 17a. The inner peripheral seal portion 18b interposed between the reinforcing ring of the main lip portion 15 and the reinforcing ring 23 of the sub lip portion 21, and outwardly formed integrally with both the seal portions 18a and 18b (upward in the figure). The lip (main lip) 18c is integrally formed, and the outward lip 18c functions as a valve body in the pressure release valve 11. That is, the lip 18c is in contact (sitting) with a predetermined amount of interference with the shaft portion 13 by fitting a garter spring (spring) 19 and the pressure inside the container B is a predetermined value. When it is below, the valve is closed, and when the pressure inside the container B exceeds a predetermined value, the lip 18c separates from the shaft portion 13 and opens. Therefore, it is possible to release the pressure exceeding the predetermined value to the outside A of the container. When the internal pressure is released, the valve immediately closes due to the resilience of the lip 18 itself and the elastic force of the garter spring 19.

  The material of the elastic body 18 is selected from saturated rubbers such as butyl rubber, halogenated butyl rubber, vinyl group-containing butyl rubber, ethylene propylene rubber (EPDM), fluorine rubber, acrylic rubber, and hydrogenated nitrile rubber. A crosslinking agent, a filler, a plasticizer, an antiaging agent, or the like is appropriately blended. In addition, as thermoplastic elastomers, olefin-based thermoplastic elastomers, ester-based thermoplastic elastomers, amide-based thermoplastic elastomers, styrene-based thermoplastic elastomers, such as hydrogenated styrene / butadiene block copolymers or hydrogenated styrene / isoprene block copolymers. It can be selected from a block copolymerization method, a graft copolymerization method, a dynamic crosslinking method, etc., and a crosslinking agent, a plasticizer, an antiaging agent, a filler or the like is appropriately blended. In the case of an elastomer such as a mixture of a resin material and rubber or a block copolymer or a graft copolymer, it can be selected from a mixture of a phenolic resin and hydrogenated nitrile rubber, butyl rubber or fluororubber.

  A metal material such as iron, copper, titanium, or nickel is used as the material of the reinforcing ring 23. Preferably, stainless steel having excellent corrosion resistance, synthetic resin, ceramic, or the like is used. When a corrosion-resistant material is used, the reinforcing ring 23 may or may not be exposed to the electrolyte side. However, when a non-corrosion-resistant material is used, it is not exposed to the electrolyte side. Must be completely buried.

Example 1
A sub lip portion 21 is disposed on the outer side A of the main lip portion 15, that is, on the atmosphere side, for preventing dust from entering and ejecting internal contents. In this embodiment, the sub lip portion 21 is The lip seal member 22 is formed by vulcanizing and bonding an elastic body 24 made of a rubber-like elastic material to the reinforcing ring 23. The reinforcing ring 23 is formed by integrally forming a flange portion 23b radially inward at one end of the cylindrical portion 23a fitted to the inner peripheral side of the cylindrical portion 17a of the reinforcing ring 17 in the main lip portion 15. An elastic body 24 is vulcanized and bonded to the tip of the flange portion 23b, and an outward (upward in the figure) lip (dust strip) 24a is provided on the elastic body 24. The outward lip 24a Acts as a dust seal for the pressure relief valve 11.

  Further, the sub lip portion 21 is provided with a communication passage 25 for opening the space C between the main lip portion 15 and the sub lip portion 21 to the atmosphere. In this embodiment, the communication passage 25 is connected to the sub lip portion 21. The hole 21 (through hole) 26 is provided in the flange portion 23 b of the reinforcing ring 23 in the portion 21. A plurality of the hole portions 26 are provided in a uniform manner (for example, three equal portions).

  The internal pressure is discharged from the inside A of the container to the outside A of the container via the space C between the main lip portion 15 and the sub lip portion 21 and the communication passage 25, but when the high pressure is discharged at once, the sub lip portion 21 may be released by pushing open.

  According to the pressure release valve 11 having the above-described configuration, the following operational effects can be achieved.

  That is, in the pressure release valve 11 having the above-described configuration, it is possible to suppress the dust outside the container A from entering the main lip portion 15 side by the sealing action by the sub lip portion 21. Therefore, it is possible to prevent the valve opening characteristics of the main lip portion 15 from being impaired or the main lip portion 15 from leaking due to the dust intrusion, accumulation / adhesion, and the like. Further, since the sealing action of the sub lip portion 21 prevents the internal contents from being ejected when the main lip portion 15 is opened, corrosion of the circuit or a short circuit occurs due to the ejection of the internal contents. Can be prevented.

  Further, it is possible to prevent a differential pressure from being generated between the space C between the main lip portion 15 and the sub lip portion 21 and the external environment. Therefore, it is possible to prevent the valve opening characteristic of the main lip portion 15 from being impaired due to the differential pressure between the space C and the external environment due to the installation of the sub lip portion 21.

  Further, since the reinforcing ring 23 of the sub lip portion 21 is fitted to the inner peripheral side of the reinforcing ring 17 of the main lip portion 15, both the lip portions 15 and 21 are assembled in advance and handled as an integrated object. It is possible. Therefore, it is possible to prevent the installation man-hours from being increased and handling becomes complicated due to the installation of the sub lip portion 21.

  In the first embodiment, the communication path 25 for opening the space C between the main lip portion 15 and the sub lip portion 21 to the atmosphere is constituted by the hole 26 provided in the reinforcing ring 23 of the sub lip portion 21. The configuration may be as follows.

Second embodiment ...
As shown in FIG. 3, a recess (groove) 27 is provided at the seal end portion of the lip 24 a in the sub lip portion 21, and this recess 27 serves as a communication path 25. A plurality of the concave portions 27 are provided in a uniform manner (for example, three equal portions).

Third embodiment ...
As shown in FIG. 4, a convex portion (projection) 28 is provided at the seal end of the lip 24a in the sub lip portion 21, and this convex portion 28 abuts on the outer peripheral surface 13a of the shaft portion 13 which is the mating seal surface. Since the lip 24a is slightly lifted, a communication passage 25 is defined by a gap (not shown) formed between the lip 24a and the outer peripheral surface 13a of the shaft portion 13 at this time. A plurality of the convex portions 28 are provided in a uniform manner (for example, three equal portions).

  Since the other configurations of the second and third embodiments are the same as those of the first embodiment, description thereof is omitted. In the case where the communication passage 25 is provided at the seal end (seal end) of the lip 24a in the sub lip portion 21 as in both embodiments, the communication passage 25 is in the radial direction as compared with the case of the first embodiment. Since it is arranged inward, there is an effect that when the pressure vessel is used obliquely or horizontally, the internal contents such as the electrolyte passing through the main lip portion 15 are not easily leaked from the communication passage 25 to the outside. .

  In addition, the configuration of the pressure release valve 11 according to the first to third embodiments can be changed within the technical scope of the present invention. For example, as shown in FIG. 5 as the fourth embodiment, a so-called beard lip 29 may be integrally formed at the tip of the lip 18 c in the main lip portion 15, and this may be used as the sub lip portion 21. Also in this case, if necessary, a communication path (not shown) is set by a hole, a concave portion, a convex portion, or the like as described above.

(A) is a longitudinal sectional view of a capacitor having a pressure release valve according to an embodiment of the present invention, (B) is a plan view of the capacitor Half cut sectional view of the pressure release valve according to the first embodiment of the present invention Half cut sectional view of the pressure relief valve according to the second embodiment of the present invention Half cut sectional view of the pressure relief valve according to the third embodiment of the present invention Half sectional view of the pressure relief valve according to the fourth embodiment of the present invention Sectional view of a pressure relief valve according to the prior art

Explanation of symbols

1 Capacitor (pressure vessel)
2 Case 3 Body element 4 Sealing plate 5 Outer can 6 Gasket 7 Lead wire 8 Electrode terminal 11 Pressure release valve 12 Valve mounting space 12a Inner peripheral surface 13 Shaft portion 13a Outer peripheral surface (mating seal surface)
14, 17b, 23b Flange part 15 Main lip part 16, 22 Lip seal member 17, 23 Reinforcement ring 17a, 23a Tubular part 18, 24 Elastic body 18a Outer peripheral seal part 18b Inner peripheral seal part 18c, 24a Lip 19 Garter spring 21 Sub lip part 25 Communication path 26 Hole part 27 Concave part 28 Convex part 29 Beard lip 0 Center axis A Container exterior B Container interior C Space

Claims (6)

In a pressure release valve (11) provided on the sealing plate (4) of the pressure vessel and opening when the pressure in the pressure vessel exceeds a predetermined value to release the pressure,
A pressure characterized by providing a sub lip portion (21) for preventing intrusion of dust and ejection of internal contents on the atmosphere side of the main lip portion (15) constituting the valve body of the pressure release valve (11). Open valve. The pressure relief valve of claim 1,
A pressure relief valve comprising a communication passage (25) for opening the space (C) between the main lip portion (15) and the sub lip portion (21) to the atmosphere. The pressure relief valve of claim 2,
The pressure release valve, wherein the communication passage (25) includes a hole (26) provided in the reinforcing ring (23) of the sub lip portion (21). The pressure relief valve of claim 2,
The pressure release valve characterized in that the communication passage (25) comprises a recess (27) provided at the lip end of the sub lip portion (21). The pressure relief valve of claim 2,
The communication passage (25) is configured such that the convex portion (28) provided at the lip end of the sub lip portion (21) contacts the mating seal surface (13a), thereby the sub lip portion (21) and the mating seal surface (13a). A pressure release valve comprising a gap portion formed therebetween. The pressure relief valve according to any one of claims 1 to 5,
A pressure characterized by integrating both lip portions (15) and (21) by fitting the reinforcing ring (23) of the sub lip portion (21) to the reinforcing ring (17) of the main lip portion (15). Open valve.

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