JP3122357U

JP3122357U - Discharge tube

Info

Publication number: JP3122357U
Application number: JP2006002361U
Authority: JP
Inventors: 孝一今井
Original assignee: Okaya Electric Industry Co Ltd
Current assignee: Okaya Electric Industry Co Ltd
Priority date: 2006-03-31
Filing date: 2006-03-31
Publication date: 2006-06-08
Anticipated expiration: 2016-03-31

Abstract

【課題】回路基板へ実装する際に放電管が転がることがなく、実装作業が容易な放電管を実現する。
【解決手段】平行配置された第１の電極12、第２の電極14、第３の電極16と、上記第１の電極12と第２の電極14間に挟まれた絶縁材料より成る第１の円筒管18、上記第２の電極14と第３の電極16間に挟まれた絶縁材料より成る第２の円筒管20より成る気密外囲器22を有し、該気密外囲器22内に放電ガスを封入して成る放電管10であって、上記第１の電極12、第２の電極14、第３の電極16の周縁12ａ，14ａ，16ａは、第１の円筒管18、第２の円筒管20の外周面18ａ，20ａから外方へ張り出すと共に、第３の電極16の外形が略正四角形状と成され、第１の電極12、第２の電極14の外形が円形状と成されている。
【選択図】図１
A discharge tube that does not roll when mounted on a circuit board and is easy to mount is realized.
A first electrode, a second electrode, and a third electrode arranged in parallel, and a first material made of an insulating material sandwiched between the first electrode and the second electrode. An airtight envelope 22 comprising a second cylindrical tube 20 made of an insulating material sandwiched between the second electrode 14 and the third electrode 16. A discharge tube 10 in which a discharge gas is sealed, and the peripheral edges 12a, 14a, 16a of the first electrode 12, the second electrode 14, and the third electrode 16 are the first cylindrical tube 18, And the outer shape of the third electrode 16 is formed in a substantially square shape, and the outer shapes of the first electrode 12 and the second electrode 14 are circular. It is made with shape.
[Selection] Figure 1

Description

この考案は、プロジェクターや自動車のメタルハライドランプ等の高圧放電ランプやガス調理器等の着火プラグに、点灯用又は着火用の定電圧を供給するためのスイッチングスパークギャップとして、或いは、サージ電圧を吸収するためのガスアレスタ（避雷管）として使用される放電管に係り、特に、回路基板への表面実装に適した放電管に関する。 This device is a switching spark gap for supplying a constant voltage for lighting or ignition to a high pressure discharge lamp such as a projector or a metal halide lamp of an automobile or a gas cooker, or absorbs a surge voltage. More particularly, the present invention relates to a discharge tube suitable for surface mounting on a circuit board.

この種の放電管として、本出願人は、先に特開２００３−７４２０号を提案した。この放電管60は、図８及び図９に示すように、両端が開口した絶縁材よりなる円筒状のケース部材62の両端開口部を、放電電極を兼ねた一対の蓋部材64，64で気密に封止することによって気密外囲器66を形成し、該気密外囲器66内に、所定の放電ガスを封入してなる。 As this type of discharge tube, the present applicant has previously proposed Japanese Patent Application Laid-Open No. 2003-7420. As shown in FIGS. 8 and 9, the discharge tube 60 is formed by sealing a cylindrical case member 62 made of an insulating material having both ends open with a pair of lid members 64 and 64 serving as discharge electrodes. A hermetic envelope 66 is formed by sealing with a predetermined discharge gas in the hermetic envelope 66.

上記蓋部材64は、気密外囲器66の中心に向けて大きく突き出た平面状の放電電極部68と、円筒状のケース部材62の端面に接する接合部70を備えており、両蓋部材64，64の放電電極部68，68間には、所定の放電間隙72が形成されている。図９に示すように、蓋部材64の接合部70は円盤状と成されている。
また、上記ケース部材62の内壁面74の円周方向に、微小放電間隙76を隔てて対向配置された一対のトリガ放電膜78，78が、複数組形成されている。一対のトリガ放電膜78，78の内、一方のトリガ放電膜78は、一方の放電電極部68と電気的に接続され、他方のトリガ放電膜78は、他方の放電電極部68と電気的に接続されている。 The lid member 64 includes a planar discharge electrode portion 68 projecting greatly toward the center of the hermetic envelope 66, and a joint portion 70 in contact with the end surface of the cylindrical case member 62. 64, a predetermined discharge gap 72 is formed between the discharge electrode portions 68, 68. As shown in FIG. 9, the joint portion 70 of the lid member 64 is formed in a disc shape.
A plurality of pairs of trigger discharge films 78 and 78 are formed in the circumferential direction of the inner wall surface 74 of the case member 62 so as to face each other with a minute discharge gap 76 therebetween. Of the pair of trigger discharge films 78, 78, one trigger discharge film 78 is electrically connected to one discharge electrode portion 68, and the other trigger discharge film 78 is electrically connected to the other discharge electrode portion 68. It is connected.

上記放電電極部68の表面には、放電開始電圧の安定に効果的なアルカリヨウ化物が含有された絶縁性の被膜80が形成されている。このアルカリヨウ化物としては、ヨウ化カリウム（ＫＩ）、ヨウ化ナトリウム（ＮａＩ）、ヨウ化セシウム（ＣｓＩ）、ヨウ化ルビジウム（ＲｂＩ）等のアルカリヨウ化物の単体又は混合物が該当する。
上記気密外囲器66内に封入する放電ガスとしては、例えば、アルゴン、ネオン、ヘリウム、キセノン等の希ガスあるいは窒素ガス等の不活性ガスの単体又は混合ガスが該当する。尚、上記放電ガス中に、ハロゲン、ＳＦ_６、ＣＯ_２、Ｏ_２、Ｈｇ等の負極性ガスやＨ_２等の消イオン時間の早いガスを混合することにより、放電後に持続放電に至る続流現象を防止することができる。 On the surface of the discharge electrode portion 68, an insulating film 80 containing an alkali iodide effective for stabilizing the discharge start voltage is formed. As this alkali iodide, the simple substance or mixture of alkali iodides, such as potassium iodide (KI), sodium iodide (NaI), cesium iodide (CsI), and rubidium iodide (RbI), corresponds.
As the discharge gas sealed in the hermetic envelope 66, for example, a rare gas such as argon, neon, helium, xenon, or an inert gas such as nitrogen gas or a mixed gas is applicable. In addition, by mixing the negative gas such as halogen, SF ₆ , CO ₂ , O ₂ , and Hg or the gas having a fast deionization time such as H ₂ in the above discharge gas, the continuation leading to the continuous discharge after the discharge. The phenomenon can be prevented.

上記構成を備えた放電管60の放電電極部68，68間に、当該放電管60の放電開始電圧以上の電圧が印加されると、トリガ放電膜78，78間の微小放電間隙76に電界が集中し、これにより微小放電間隙76に電子が放出されてトリガ放電としての沿面コロナ放電が発生する。次いで、この沿面コロナ放電は、電子のプライミング効果によってグロー放電へと移行する。そして、このグロー放電が放電電極部68，68間の放電間隙72へと転移し、主放電としてのアーク放電に移行するのである。 When a voltage equal to or higher than the discharge start voltage of the discharge tube 60 is applied between the discharge electrode portions 68, 68 of the discharge tube 60 having the above-described configuration, an electric field is generated in the minute discharge gap 76 between the trigger discharge films 78, 78. As a result, electrons are emitted into the minute discharge gap 76, and creeping corona discharge as a trigger discharge is generated. Next, this creeping corona discharge shifts to glow discharge due to an electron priming effect. Then, the glow discharge is transferred to the discharge gap 72 between the discharge electrode portions 68 and 68, and is transferred to arc discharge as the main discharge.

上記放電管60は、放電電極を兼ねた一対の蓋部材64，64と回路基板82とをハンダ84を介して接続することにより、回路基板82への表面実装が可能である。
特開２００３−７４２０号 The discharge tube 60 can be surface-mounted on the circuit board 82 by connecting the pair of lid members 64 and 64 that also serve as discharge electrodes and the circuit board 82 via the solder 84.
JP 2003-7420 A

上記放電管60は全長がミリ単位の大きさであるが、円筒状のケース部材62の両端面に、放電電極を兼ねた一対の蓋部材64，64の円盤状の接合部70を接合させて成り、その外形が円形状と成されていることから、回路基板82へ実装する際に放電管60が転がり易いため位置決めが難しく、放電管60の実装作業が困難であった。 The total length of the discharge tube 60 is in millimeters, but a pair of lid members 64 and 64 that also serve as discharge electrodes are joined to both end faces of a cylindrical case member 62 to join the disc-like joint portions 70. Since the outer shape of the discharge tube 60 is circular, the discharge tube 60 easily rolls when mounted on the circuit board 82, so that positioning is difficult, and mounting of the discharge tube 60 is difficult.

この考案は、従来の上記問題に鑑みてなされたものであり、その目的とするところは、回路基板へ実装する際に放電管が転がることがなく、実装作業が容易な放電管を実現することにある。 The present invention has been made in view of the above-mentioned problems, and the object of the invention is to realize a discharge tube that is easy to mount without causing the discharge tube to roll when mounted on a circuit board. It is in.

上記目的を達成するため、請求項１に係る放電管は、平行配置された第１の電極、第２の電極、第３の電極と、上記第１の電極と第２の電極間に挟まれた絶縁材料より成る第１の円筒管、上記第２の電極と第３の電極間に挟まれた絶縁材料より成る第２の円筒管より成る気密外囲器を有し、該気密外囲器内に放電ガスを封入して成る放電管であって、上記第１の電極、第２の電極、第３の電極の周縁は、第１の円筒管、第２の円筒管の外周面から外方へ張り出すと共に、第１の電極、第２の電極、第３の電極の内、何れか１つの電極の外形が多角形状又は略多角形状と成され、他の２つの電極の外形が円形状と成されていることを特徴とする。 In order to achieve the above object, a discharge tube according to claim 1 is sandwiched between a first electrode, a second electrode, and a third electrode arranged in parallel, and the first electrode and the second electrode. A hermetic envelope comprising a first cylindrical tube made of an insulating material and a second cylindrical tube made of an insulating material sandwiched between the second electrode and the third electrode. A discharge tube in which a discharge gas is sealed, and the peripheral edges of the first electrode, the second electrode, and the third electrode are outside the outer peripheral surfaces of the first cylindrical tube and the second cylindrical tube. The outer shape of any one of the first electrode, the second electrode, and the third electrode is formed into a polygonal shape or a substantially polygonal shape, and the outer shapes of the other two electrodes are circular. It is characterized by its shape.

また、請求項２に係る放電管は、第１の電極、第２の電極、第３の電極の内、何れか１つの電極の外形が正多角形状又は略正多角形状と成され、また、外形が円形状と成された他の２つの電極が、外形が正多角形状又は略正多角形状と成された電極の全ての辺に内接する位置関係と成されていることを特徴とする。例えば、第１の電極、第２の電極、第３の電極の内、何れか１つの電極の外形が正四角形状又は略正四角形状と成され、また、外形が円形状と成された他の２つの電極が、外形が正四角形状又は略正四角形状と成された電極の四辺に内接する位置関係と成されている場合が該当する。 In the discharge tube according to claim 2, the outer shape of any one of the first electrode, the second electrode, and the third electrode is a regular polygonal shape or a substantially regular polygonal shape. The other two electrodes having a circular outer shape are in a positional relationship inscribed in all the sides of the electrode whose outer shape is a regular polygonal shape or a substantially regular polygonal shape. For example, any one of the first electrode, the second electrode, and the third electrode has an outer shape of a regular square shape or a substantially regular square shape, and the outer shape has a circular shape. This case corresponds to a case where the two electrodes are in a positional relationship inscribed in the four sides of the electrode whose outer shape is a regular square shape or a substantially regular square shape.

本考案に係る放電管にあっては、第１の電極、第２の電極、第３の電極の周縁が、第１の円筒管、第２の円筒管の外周面から外方へ張り出すと共に、第１の電極、第２の電極、第３の電極の内、何れか１つの電極の外形が多角形状又は略多角形状と成されていることから、回路基板へ実装する際に放電管が転がることを防止でき、実装作業を容易に行うことができる。
尚、本考案の放電管において、第１の電極、第２の電極、第３の電極の内、１つの電極の外形だけを多角形状又は略多角形状と成すと共に、他の２つの電極の外形を円形状と成したのは次の理由による。すなわち、第１の電極、第２の電極、第３の電極の内、２つ以上の電極の外形を多角形状又は略多角形状と成した場合にも放電管の転がりは防止できるものの、外形が多角形状又は略多角形状と成された２つ以上の電極が正確に対称な位置関係となるように第１の円筒管、第２の円筒管に取付されていない場合には、放電管を実装した際に何れかの電極が回路基板から浮き上がる等してガタツキが生じ、実装時の安定性に欠けることとなる。これに対し、本考案の如く、１つの電極の外形だけを多角形状又は略多角形状とし、他の２つの電極の外形を円形状としておけば、多角形状又は略多角形状と成された１つの電極を回路基板上に載置すると、円形状と成された他の２つの電極も回路基板に確実に当接・載置されるため、放電管を回路基板に安定的に実装できる。 In the discharge tube according to the present invention, the peripheral edges of the first electrode, the second electrode, and the third electrode protrude outward from the outer peripheral surfaces of the first cylindrical tube and the second cylindrical tube. Since the outer shape of any one of the first electrode, the second electrode, and the third electrode is a polygonal shape or a substantially polygonal shape, the discharge tube is mounted when mounted on the circuit board. Rolling can be prevented and mounting work can be easily performed.
In the discharge tube according to the present invention, only one of the first electrode, the second electrode, and the third electrode has a polygonal shape or a substantially polygonal shape, and the other two electrode outer shapes. The reason for forming a circle is as follows. That is, although the discharge tube can be prevented from rolling even when the outer shape of two or more of the first electrode, the second electrode, and the third electrode is made polygonal or substantially polygonal, the outer shape is When two or more electrodes formed in a polygonal shape or a substantially polygonal shape are not attached to the first cylindrical tube and the second cylindrical tube so as to have an accurate symmetrical positional relationship, a discharge tube is mounted. In this case, any one of the electrodes is lifted off the circuit board to cause backlash, resulting in lack of stability during mounting. On the other hand, if only the outer shape of one electrode is polygonal or substantially polygonal and the outer shape of the other two electrodes is circular as in the present invention, one polygonal or substantially polygonal shape is formed. When the electrodes are placed on the circuit board, the other two electrodes having a circular shape are also securely abutted and placed on the circuit board, so that the discharge tube can be stably mounted on the circuit board.

また、第１の電極、第２の電極、第３の電極の内、何れか１つの電極の外形が正多角形状（例えば正四角形状）又は略正多角形状（例えば略正四角形状）と成し、また、外形が円形状と成された他の２つの電極が、外形が正多角形状（例えば正四角形状）又は略正多角形状（例えば略正四角形状）と成された電極の全ての辺に内接する位置関係と成すことにより、放電管を回路基板に実装した場合、放電管を回路基板の表面と平行に配置することができ、実装時の安定性が向上する。 In addition, the outer shape of any one of the first electrode, the second electrode, and the third electrode is a regular polygonal shape (for example, a regular square shape) or a substantially regular polygonal shape (for example, a substantially regular square shape). In addition, the other two electrodes whose outer shape is circular are all of the electrodes whose outer shape is a regular polygonal shape (for example, a regular square shape) or a substantially regular polygonal shape (for example, a substantially regular square shape). When the discharge tube is mounted on the circuit board, the discharge tube can be arranged in parallel to the surface of the circuit board, and the stability during mounting is improved.

本考案に係る放電管10は三極構造の放電管であり、図１及び図２に示すように、平行配置された第１の電極12、第２の電極14、第３の電極16と、上記第１の電極12と第２の電極14間に挟まれたセラミック等の絶縁材料より成る第１の円筒管18、上記第２の電極14と第３の電極16間に挟まれた絶縁材料より成る第２の円筒管20より成る気密外囲器22を有している。 A discharge tube 10 according to the present invention is a triode discharge tube, and as shown in FIGS. 1 and 2, a first electrode 12, a second electrode 14, a third electrode 16 arranged in parallel, A first cylindrical tube 18 made of an insulating material such as ceramic sandwiched between the first electrode 12 and the second electrode 14; an insulating material sandwiched between the second electrode 14 and the third electrode 16; It has an airtight envelope 22 made of a second cylindrical tube 20 made of the same.

中央に配置された第２の電極14は接地電極であり、第１の円筒管18と第２の円筒管20の内部空間同士を連通させる通気孔24が形成されている。
また、左右に配置された第１の電極12、第３の電極16は、気密外囲器22の中心に向けて突出して気密外囲器22内に配置される放電電極部26を備えており、第１の電極12及び第３の電極16の放電電極部26，26間には放電間隙28が形成されている。また、第１の電極12、第３の電極16の外側面には、窪み12ｂ，16ｂが形成されている。
上記第１の電極12、第２の電極14、第３の電極16は、無酸素銅や、無酸素銅にジルコニウム（Ｚｒ）を含有させたジルコニウム銅で構成されている。また、第１の電極12、第２の電極14、第３の電極16と、第１の円筒管18、第２の円筒管20とは、銀ろう等のシール材（図示せず）を介して気密に接合される。 The second electrode 14 disposed in the center is a ground electrode, and a vent hole 24 is formed to communicate the internal spaces of the first cylindrical tube 18 and the second cylindrical tube 20 with each other.
Further, the first electrode 12 and the third electrode 16 arranged on the left and right are provided with discharge electrode portions 26 that protrude toward the center of the hermetic envelope 22 and are arranged in the hermetic envelope 22. A discharge gap 28 is formed between the discharge electrode portions 26 of the first electrode 12 and the third electrode 16. In addition, recesses 12 b and 16 b are formed on the outer surfaces of the first electrode 12 and the third electrode 16.
The first electrode 12, the second electrode 14, and the third electrode 16 are made of oxygen-free copper or zirconium copper containing oxygen-free copper containing zirconium (Zr). The first electrode 12, the second electrode 14, the third electrode 16, the first cylindrical tube 18 and the second cylindrical tube 20 are connected via a sealing material (not shown) such as silver brazing. And airtightly joined.

上記第１の電極12、第２の電極14、第３の電極16の周縁12ａ，14ａ，16ａは、第１の円筒管18、第２の円筒管20の外周面18ａ，20ａから外方へ張り出している。
図３及び図４に示すように第１の電極12の外形は円形状と成され、図５及び図６に示すように、第３の電極16の外形は隅丸の略正四角形状と成され、図７に示すように第２の電極14の外形は円形状と成されている。
また、外形が円形状と成された第１の電極12及び第２の電極14が、外形が略正四角形状と成された第３の電極16の四辺に内接する位置関係と成されている。 The peripheral edges 12a, 14a, 16a of the first electrode 12, the second electrode 14, and the third electrode 16 are outward from the outer peripheral surfaces 18a, 20a of the first cylindrical tube 18 and the second cylindrical tube 20. It is overhanging.
As shown in FIGS. 3 and 4, the outer shape of the first electrode 12 has a circular shape, and as shown in FIGS. 5 and 6, the outer shape of the third electrode 16 has a substantially square shape with rounded corners. As shown in FIG. 7, the outer shape of the second electrode 14 is circular.
Further, the first electrode 12 and the second electrode 14 whose outer shape is circular are in a positional relationship inscribed in the four sides of the third electrode 16 whose outer shape is a substantially square shape. .

上記気密外囲器22内には、所定の放電ガスが封入されている。この放電ガスとしては、例えば、アルゴン、ネオン、ヘリウム、キセノン等の希ガスあるいは窒素ガス等の不活性ガスの単体又は混合ガスが該当する。 A predetermined discharge gas is sealed in the hermetic envelope 22. As this discharge gas, for example, a rare gas such as argon, neon, helium, or xenon, or an inert gas such as nitrogen gas or a mixed gas is applicable.

本考案の上記放電管10は、第１の電極12、第２の電極14、第３の電極と回路基板31とをハンダ33を介して接続することにより、回路基板31への表面実装が可能である。 The discharge tube 10 of the present invention can be surface-mounted on the circuit board 31 by connecting the first electrode 12, the second electrode 14, and the third electrode to the circuit board 31 via the solder 33. It is.

本考案の上記放電管10にあっては、第１の電極12及び第３の電極16間に、当該放電管10の放電開始電圧以上の電圧が印加されると、放電間隙28において放電が生成されるのである。 In the discharge tube 10 of the present invention, when a voltage higher than the discharge start voltage of the discharge tube 10 is applied between the first electrode 12 and the third electrode 16, a discharge is generated in the discharge gap 28. It is done.

而して、本考案の放電管10にあっては、第１の電極12、第２の電極14、第３の電極16の周縁12ａ，14ａ，16ａが、第１の円筒管18、第２の円筒管20の外周面18ａ，20ａから外方へ張り出すと共に、第３の電極16の外形が略正四角形状と成されていることから、回路基板31へ実装する際に放電管10が転がることを防止でき、実装作業を容易に行うことができる。
尚、本考案の放電管10において、第１の電極12、第２の電極14、第３の電極16の内、１つの電極（第３の電極16）の外形だけを「略正四角形状」と成すと共に、他の２つの電極（第１の電極12、第２の電極14）の外形を「円形状」と成したのは次の理由による。すなわち、第１の電極12、第２の電極14、第３の電極16の内、２つ以上の電極の外形を「略正四角形状」と成した場合にも放電管10の転がりは防止できるものの、外形が「略正四角形状」と成された２つ以上の電極が正確に対称な位置関係となるように第１の円筒管18、第２の円筒管20に取付されていない場合には、放電管10を実装した際に何れかの電極が回路基板31から浮き上がる等してガタツキが生じ、実装時の安定性に欠けることとなる。これに対し、本考案の如く、１つの電極（第３の電極16）の外形だけを「略正四角形状」とし、他の２つの電極（第１の電極12、第２の電極14）の外形を「円形状」としておけば、「略正四角形状」と成された１つの電極（第３の電極16）を回路基板31上に載置すると、「円形状」と成された他の２つの電極（第１の電極12、第２の電極14）も回路基板31に確実に当接・載置されるため、放電管10を回路基板31に安定的に実装できる。 Thus, in the discharge tube 10 of the present invention, the peripheral edges 12a, 14a and 16a of the first electrode 12, the second electrode 14, and the third electrode 16 are the first cylindrical tube 18 and the second The cylindrical tube 20 projects outward from the outer peripheral surfaces 18a, 20a, and the outer shape of the third electrode 16 is a substantially square shape. Therefore, when the discharge tube 10 is mounted on the circuit board 31, Rolling can be prevented and mounting work can be easily performed.
In the discharge tube 10 of the present invention, only the outer shape of one of the first electrode 12, the second electrode 14, and the third electrode 16 (the third electrode 16) is a “substantially square shape”. The other two electrodes (the first electrode 12 and the second electrode 14) are formed in a “circular shape” for the following reason. That is, the discharge tube 10 can be prevented from rolling even when the outer shape of two or more of the first electrode 12, the second electrode 14, and the third electrode 16 is formed in a “substantially square shape”. However, when two or more electrodes having an outer shape of “substantially square shape” are not attached to the first cylindrical tube 18 and the second cylindrical tube 20 so as to have an accurate symmetrical positional relationship. In other words, when the discharge tube 10 is mounted, any one of the electrodes floats from the circuit board 31 to cause backlash, resulting in lack of stability during mounting. On the other hand, as in the present invention, only the outer shape of one electrode (third electrode 16) is made to be a “substantially square shape”, and the other two electrodes (first electrode 12, second electrode 14) If the outer shape is a “circular shape”, when one electrode (third electrode 16) formed in a “substantially square shape” is placed on the circuit board 31, another circular shape is formed. Since the two electrodes (the first electrode 12 and the second electrode 14) are also securely brought into contact with and placed on the circuit board 31, the discharge tube 10 can be stably mounted on the circuit board 31.

また、本考案の放電管10は、外形が円形状と成された第１の電極12及び第２の電極14が、外形が略正四角形状と成された第３の電極16の四辺に内接する位置関係と成されているので、放電管10を回路基板31に実装した場合、放電管10を回路基板31の表面と平行に配置することができ、実装時の安定性が向上する。 Further, in the discharge tube 10 of the present invention, the first electrode 12 and the second electrode 14 having a circular outer shape are disposed on the four sides of the third electrode 16 having a substantially square shape. Since the discharge tube 10 is mounted on the circuit board 31, the discharge tube 10 can be disposed in parallel with the surface of the circuit board 31 and the stability during mounting is improved.

上記においては、第３の電極16を「略正四角形状」と成した場合について説明したが、第１の電極12或いは第２の電極14を「略正四角形状」としても良く、要するに、第１の電極12、第２の電極14、第３の電極16の内、何れか１つの電極の外形を「略正四角形状」と成すと共に、他の２つの電極の外形を「円形状」と成せば良い。 In the above description, the case where the third electrode 16 has a “substantially square shape” has been described. However, the first electrode 12 or the second electrode 14 may have a “substantially square shape”. The outer shape of any one of the first electrode 12, the second electrode 14, and the third electrode 16 is a “substantially square shape”, and the outer shape of the other two electrodes is a “circular shape”. Just do it.

また、上記においては、第３の電極16の外形を「隅丸の略正四角形状」と成した場合を例に挙げて説明したが、「角を面取りした略正四角形状」、「正四角形状」、「四角形状」等であっても勿論良い。更に、三角形状や六角形状等、要するに、多角形状、或いは略多角形状と成されていれば良い。
尚、第１の電極12、第２の電極14、第３の電極16の内、何れか１つの電極の外形を「略正四角形状」と成した場合には、外形が円形状と成された他の２つの電極が、外形が「正多角形状」又は「略正多角形状」と成された電極の全ての辺に内接する位置関係と成すことにより、放電管10を回路基板31に実装した場合、放電管10を回路基板31の表面と平行に配置することができ、実装時の安定性が向上する。 Further, in the above description, the case where the outer shape of the third electrode 16 is “a substantially square shape with rounded corners” has been described as an example, but “a substantially square shape with chamfered corners”, “a regular square shape” Of course, “shape”, “rectangular shape” and the like may be used. Furthermore, it may be formed into a polygonal shape or a substantially polygonal shape such as a triangular shape or a hexagonal shape.
In addition, when the outer shape of any one of the first electrode 12, the second electrode 14, and the third electrode 16 is a "substantially square shape", the outer shape is a circular shape. The other two electrodes have a positional relationship inscribed in all sides of the electrode whose outer shape is a “regular polygon shape” or “substantially regular polygon shape”, so that the discharge tube 10 is mounted on the circuit board 31. In this case, the discharge tube 10 can be arranged in parallel with the surface of the circuit board 31, and the stability during mounting is improved.

本考案に係る放電管を示す概略断面図である。It is a schematic sectional drawing which shows the discharge tube which concerns on this invention. 本考案に係る放電管を示す正面図である。It is a front view which shows the discharge tube which concerns on this invention. 本考案に係る放電管を示す左側面図である。It is a left view which shows the discharge tube which concerns on this invention. 図１のＢ−Ｂ概略断面図である。It is BB schematic sectional drawing of FIG. 本考案に係る放電管を示す右側面図である。It is a right view which shows the discharge tube which concerns on this invention. 図１のＣ−Ｃ概略断面図である。It is CC schematic sectional drawing of FIG. 図１のＤ−Ｄ概略断面図である。It is DD schematic sectional drawing of FIG. 従来の放電管を示す概略断面図である。It is a schematic sectional drawing which shows the conventional discharge tube. 図８のＡ−Ａ概略断面図である。It is an AA schematic sectional drawing of FIG.

Explanation of symbols

10 放電管
12 第１の電極
14 第２の電極
16 第３の電極
18 第１の円筒管
20 第２の円筒管
22 気密外囲器
24 通気孔
26 放電電極部
28 放電間隙
10 discharge tube
12 First electrode
14 Second electrode
16 Third electrode
18 First cylindrical tube
20 Second cylindrical tube
22 Airtight envelope
24 Vent
26 Discharge electrode
28 Discharge gap

Claims

A first cylindrical tube made of an insulating material sandwiched between the first electrode and the second electrode, the second electrode, and the first electrode, the second electrode, and the third electrode arranged in parallel A discharge tube having a hermetic envelope made of a second cylindrical tube made of an insulating material sandwiched between the first electrode and the third electrode, wherein a discharge gas is sealed in the hermetic envelope, The peripheral edges of the first electrode, the second electrode, and the third electrode protrude outward from the outer peripheral surface of the first cylindrical tube and the second cylindrical tube, and the first electrode, the second electrode, A discharge tube characterized in that an outer shape of any one of the third electrodes is a polygonal shape or a substantially polygonal shape, and an outer shape of the other two electrodes is a circular shape.

Of the first electrode, the second electrode, and the third electrode, the outer shape of any one of the electrodes is a regular polygonal shape or a substantially regular polygonal shape, and the other 2 whose outer shape is a circular shape. The discharge tube according to claim 1, wherein the two electrodes are in a positional relationship inscribed in all sides of the electrode whose outer shape is a regular polygonal shape or a substantially regular polygonal shape.

Of the first electrode, the second electrode, and the third electrode, the outer shape of any one of the electrodes is a regular square shape or a substantially regular square shape, and the other two whose outer shapes are circular shapes. 2. The discharge tube according to claim 1, wherein the two electrodes are in a positional relationship inscribed in the four sides of the electrode whose outer shape is a regular square shape or a substantially regular square shape.