WO2014189088A1 - Procédé de production de bougie d'allumage pour moteur à combustion interne - Google Patents

Procédé de production de bougie d'allumage pour moteur à combustion interne Download PDF

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Publication number
WO2014189088A1
WO2014189088A1 PCT/JP2014/063507 JP2014063507W WO2014189088A1 WO 2014189088 A1 WO2014189088 A1 WO 2014189088A1 JP 2014063507 W JP2014063507 W JP 2014063507W WO 2014189088 A1 WO2014189088 A1 WO 2014189088A1
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WO
WIPO (PCT)
Prior art keywords
base material
discharge
electrode
chip
spark plug
Prior art date
Application number
PCT/JP2014/063507
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English (en)
Japanese (ja)
Inventor
勇樹 村山
阿部　信男
弘一 坂入
邦弘 田中
Original Assignee
株式会社デンソー
田中貴金属工業株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
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Publication date
Application filed by 株式会社デンソー, 田中貴金属工業株式会社 filed Critical 株式会社デンソー
Priority to CN201480028953.7A priority Critical patent/CN105247747B/zh
Priority to EP14801406.1A priority patent/EP3001519B1/fr
Publication of WO2014189088A1 publication Critical patent/WO2014189088A1/fr

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01T—SPARK GAPS; OVERVOLTAGE ARRESTERS USING SPARK GAPS; SPARKING PLUGS; CORONA DEVICES; GENERATING IONS TO BE INTRODUCED INTO NON-ENCLOSED GASES
    • H01T13/00—Sparking plugs
    • H01T13/20—Sparking plugs characterised by features of the electrodes or insulation
    • H01T13/39—Selection of materials for electrodes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01T—SPARK GAPS; OVERVOLTAGE ARRESTERS USING SPARK GAPS; SPARKING PLUGS; CORONA DEVICES; GENERATING IONS TO BE INTRODUCED INTO NON-ENCLOSED GASES
    • H01T21/00—Apparatus or processes specially adapted for the manufacture or maintenance of spark gaps or sparking plugs
    • H01T21/02—Apparatus or processes specially adapted for the manufacture or maintenance of spark gaps or sparking plugs of sparking plugs

Definitions

  • the present invention relates to a method of manufacturing a spark plug for an internal combustion engine, in which at least one of a center electrode and a ground electrode that are opposed to each other with a spark discharge gap formed therebetween is provided with a discharge tip.
  • a high efficiency engine that performs supercharging with a low displacement is required.
  • These high-efficiency engines employ a high-performance spark plug having a discharge chip at least one of the center electrode and the ground electrode in order to improve ignition performance.
  • a noble metal such as Pt, Ir, Ru, Rh, Pd, Os or a rare metal is used in order to ensure wear resistance.
  • a spark plug in which a discharge chip is constituted by a composite material (Clad Material) of a base material joint portion joined to an electrode base material and a discharge portion facing a spark discharge gap.
  • Patent Document 1 discloses a method of manufacturing a discharge chip made of a composite material formed by joining a base material joint and a discharge part by resistance welding and diffusion bonding. It is disclosed.
  • the discharge chip (clad electrode) described in Patent Document 1 has the following problems. That is, since this discharge chip is obtained by joining the discharge part and the base material joint part, a step is likely to occur between them. Therefore, a sharp corner portion of the base material joint portion is likely to appear on the side portion of the discharge chip. Then, when this discharge chip is used for the ground electrode or the center electrode of the spark plug, the electric field strength near the sharp corner of the base material joint becomes high. Therefore, the discharge spark tends to fly to the sharp corners of the base material joint at the side of the discharge chip, and it may be difficult to form a normal discharge spark.
  • a discharge chip is produced by punching out a composite plate obtained by bonding the material of the discharge part and the material of the base material joint part, a discharge chip without a step between the discharge part and the base material joint part can be obtained. Is possible. However, when the composite plate after being punched is regenerated, it is necessary to separate the two kinds of materials, and there is a problem that the regeneration cost increases. On the contrary, when the discharge part and the base material joint part are joined after punching, the diameter of the base material joint part is made larger than the diameter of the discharge part in order to make the joint area of both constant. There is a need. As a result, a step is generated between the base material joined portion and the discharge portion, and a sharp corner portion of the base material joined portion is formed on the side portion of the discharge chip.
  • the present invention has been made in view of such a background, and an object of the present invention is to provide a method for manufacturing a spark plug for an internal combustion engine that can suppress a spark to a base material joint.
  • the present invention provides a discharge chip in which at least one of a center electrode and a ground electrode which are opposed to each other with a spark discharge gap formed therebetween is bonded to an electrode base material so as to protrude toward the spark discharge gap.
  • a method of manufacturing a spark plug for an internal combustion engine is provided. This method A discharge part disposed on the spark discharge gap side and a base material joint part made of a material having a melting point lower than that of the discharge part and joined to the electrode base material are joined together to produce the discharge chip.
  • Chip manufacturing process A temporary joining step of temporarily joining the discharge tip to the electrode base material at the base material joint by resistance welding; The main joining which joins the said discharge chip to the said electrode base material so that the side surface of the said discharge part and the surface of the said electrode base material may be smoothly connected with the connection surface which does not have a sharp edge by laser welding. And a process.
  • a sharp corner portion of the base material joint portion does not appear on the side portion of the discharge chip. That is, it is possible to prevent a portion where the electric field strength is locally increased from being formed in the base material joint. As a result, it is possible to suppress sparks to the base material joint.
  • the discharge chip can be easily joined to the electrode base material so that the side surface of the discharge part and the surface of the electrode base material are smoothly connected.
  • FIG. 1 The side view of the front-end
  • FIG. 1 The (a) front view and (b) top view of the discharge chip obtained by the chip
  • FIG. The front view which shows the state which carried out the temporary joining of the discharge chip to the electrode base material by the temporary joining process in Example 1.
  • FIG. The front view which shows the state which welded the discharge tip to the electrode base material by the main joining process in Example 1.
  • FIG. Sectional explanatory drawing which shows the state which welded the discharge tip to the electrode base material by the main joining process in Example 2.
  • FIG. Sectional explanatory drawing which shows the
  • the center electrode may include the discharge tip, the ground electrode may include the discharge tip, or both the center electrode and the ground electrode may include the discharge tip. You may have.
  • the spark plug can be used as ignition means in a combustion chamber of an internal combustion engine such as an automobile engine.
  • the discharge chip obtained in the chip manufacturing process may have a diameter of the base material joint portion larger than a diameter of the discharge portion. In this case, it is easy to stably join the discharge portion and the base material joint portion in the chip manufacturing process. However, when the diameter of the base material joint is larger than the diameter of the discharge part, a step is generated between the two, and a sharp corner of the base material joint appears. If the discharge tip is bonded to the electrode base material with the sharp corners still appearing, the sparks of the spark plug are likely to fly to the base material bonding portion.
  • the discharge chip and the electrode base material are joined to the electrode base material so that the side surface of the discharge portion and the surface of the electrode base material are smoothly connected by a connection surface having no sharp edge.
  • a connection surface having no sharp edge it is possible to take a sharp corner of the base material joint.
  • the spark to the base material junction part can be suppressed effectively.
  • Example 1 Examples of the method for manufacturing a spark plug for the internal combustion engine will be described with reference to FIGS.
  • the spark plug 1 obtained by the manufacturing method of this example has a spark discharge gap 11 in which a center electrode 2 and a ground electrode 3 that are opposed to each other with a spark discharge gap 11 formed therebetween.
  • Discharge chips 4 and 5 joined to the electrode base materials 20 and 30 so as to protrude toward the surface, respectively.
  • the discharge tip 5 in the ground electrode 3 is made of a discharge part 51 disposed on the spark discharge gap 11 side, and a base material joined to the electrode base material 30 while being made of a material having a melting point lower than that of the discharge part 51.
  • the joining portion 52 is joined to each other.
  • the discharge tip 4 in the center electrode 2 is not a composite member.
  • the manufacturing method of the spark plug 1 of this example includes a chip manufacturing process, a temporary bonding process, and a main bonding process described below. That is, the ground electrode 3 formed by joining the discharge chip 5 to the electrode base material 30 is formed through the following steps.
  • the chip manufacturing process as shown in FIG. 2, the discharge part 5 and the base material bonding part 52 are bonded together to manufacture the discharge chip 5.
  • the temporary joining step the discharge chip 5 is temporarily joined to the electrode base material 30 at the base material joint portion 52 by resistance welding as shown in FIG.
  • the main joining step as shown in FIG. 4, by melting and solidifying a part of the base material joining part 52 and a part of the electrode base material 30 by laser welding, the side surface 511 and the electrode of the discharge part 51 are solidified.
  • the discharge chip 5 is joined to the electrode base material 30 so that the surface of the base material 30 is smoothly connected to the connection surface 523 having no sharp edge.
  • the electrode base material 30 of the ground electrode 3 extends from the distal end of the housing 12 of the spark plug 1 to the distal end side (lower side in FIG. 1) and is bent toward the central axis.
  • the electrode base material 20 of the center electrode 2 is held inside the insulator 13 held inside the housing 12.
  • Both the housing 12 and the electrode base material 30 of the ground electrode 3 are made of a nickel alloy.
  • the electrode base material 20 of the center electrode 2 is also made of a nickel alloy.
  • the electrode base material 30 of the ground electrode 3 includes a facing surface 31 that faces the center electrode 2 in the axial direction of the spark plug 1 (hereinafter simply referred to as “plug axial direction”).
  • the discharge chip 5 is joined.
  • the discharge chip 4 is joined to the tip of the electrode base material 20 of the center electrode 2 facing the facing surface 31 in the plug axis direction.
  • the discharge tip 4 of the center electrode 2 is not a composite member but is made of a noble metal tip such as an iridium alloy. That is, the discharge tip 4 made of a noble metal is joined to the tip of the electrode base material 20 of the center electrode 2 by welding or the like.
  • the discharge chip 5 of the ground electrode 3 is composed of a composite member in which the discharge part 51 and the base material joining part 52 are joined to each other as described above.
  • the above-described chip manufacturing process, provisional bonding process, and main bonding process are performed. An example of each process will be specifically described below.
  • a discharge part 51 made of a material having a relatively high melting point (for example, a melting point of 1700 ° C. or higher) and a base material joining part 52 made of a material having a lower melting point than the discharge part 51 are prepared.
  • a material having a relatively high melting point for example, a melting point of 1700 ° C. or higher
  • a base material joining part 52 made of a material having a lower melting point than the discharge part 51 are prepared.
  • the material of the discharge part 51 for example, Pt (platinum), Ir (iridium), Ru (ruthenium), Rh (rhodium), Pd (palladium), Os (osmium), or the like can be used.
  • a Ni (nickel) alloy can be used as this Ni alloy. As this Ni alloy, for example, one having a melting point of 1400 to 1450 ° C. can be used.
  • a cylindrical discharge part 51 and a base material joining part 52 are obtained.
  • the diameter of the base material joint 52 is larger than the diameter of the discharge part 51.
  • the cylindrical discharge portion 51 and the base material joint portion 52 formed in this way are overlapped in the axial direction while matching the central axes of both. And in the state which pressed both mutually, heat processing is performed and the discharge part 51 and the base material junction part 52 are joined by diffusion joining. Thereby, the discharge chip 5 as a composite member (Clad Material) is obtained.
  • a diffusion layer (not shown) in which atoms of the respective materials of the discharge part 51 and the base material bonding part 52 diffuse to each other. Is formed.
  • the diameter of the base material joint portion 52 is larger than the diameter of the discharge portion. Therefore, at this stage, a step is formed between the base material joint portion 52 and the discharge portion 51, and a sharp corner 521 of the base material joint portion 52 exists at this step portion.
  • the discharge chip 5 obtained in the chip manufacturing step is temporarily bonded to the facing surface 31 of the electrode base material 30 as shown in FIG.
  • Temporary joining is performed by resistance welding. That is, the discharge chip 5 is brought into contact with a predetermined position on the facing surface 31 of the electrode base material 30 on the surface on the base material joint portion 52 side.
  • a current is passed between the discharge tip 5 and the electrode base material 30 while the discharge tip 5 and the electrode base material 30 are sandwiched between the pair of resistance welding electrodes. Thereby, the discharge tip 5 is welded to the electrode base material 30 by Joule heat and temporarily joined.
  • the discharge tip 5 is joined to the electrode base material 30 by laser welding as shown in FIG. That is, as shown in FIG. 5, the laser light L is irradiated from the periphery of the joined portion to the discharge chip 5 temporarily joined to the electrode base material 30.
  • the laser light L is irradiated from a plurality of locations over the entire circumference of the joint portion with respect to the electrode base material 30.
  • laser welding is performed at a temperature lower than the melting point of the discharge part 51. That is, in the main joining step, the discharge part 51 is not melted, and a part of the base material joint part 52 and a part of the electrode base material 30 are melted.
  • a molten portion 522 in which the base material joint 52 and the electrode base material 30 are melted and solidified is formed in an annular shape on the outer periphery of the base material joint 52.
  • connection surface 523 that smoothly connects the surface of the electrode base material 30 (opposing surface 31) is formed.
  • the connection surface 523 has a shape in which a cross section of a plane passing through the central axis of the discharge chip 5 smoothly connects a curve and a straight line, and does not have a sharp edge.
  • the discharge chip 5 is joined to the electrode base material 30 by melting and solidifying a part of the base material joint portion 52 and a part of the electrode base material 30 by laser welding.
  • the discharge chip 5 is joined to the electrode base material 30 so that the side surface 511 of the discharge part 51 and the opposing surface 31 of the electrode base material 30 are connected by the connection surface 523 having no sharp edge. Therefore, in the spark plug 1 obtained, the sharpened corners 521 (FIG. 3) of the base material joint 52 do not appear on the side of the discharge chip 5, and the region where the electric field strength is locally increased is the base material. It is possible to prevent the joint portion 52 from being formed. As a result, sparks to the base material joint 52 can be suppressed.
  • the outer shape of the base material bonding portion 52 can be easily formed along the side surface 511 of the discharge portion 51 and the facing surface 31 of the electrode base material 30. Therefore, the discharge chip 5 is easily joined to the electrode base material 30 so that the side surface 511 of the discharge part 51 and the facing surface 31 of the electrode base material 30 are connected by the connection surface 523 having no sharp edge. Can do.
  • the diameter of the base material joint portion 52 is larger than the diameter of the discharge portion 51.
  • the diameter of the base material joint portion 52 is larger than the diameter of the discharge portion 51, a step is generated between them, and a sharp corner portion 521 of the base material joint portion 52 appears.
  • the discharge chip 5 is connected to the electrode base material so that the side surface 511 of the discharge part 51 and the facing surface 31 of the electrode base material 30 are connected by the connection surface 523 having no sharp edge.
  • the sharp corner 521 of the base material bonding portion 52 can be taken.
  • the side surface of the discharge chip 5 can be smoothly connected to the surface (opposite surface 31) of the electrode base material 30 from the side surface 511 of the discharge part 51 by the connection surface 523 which does not have a sharp edge. As a result, it is possible to effectively suppress the sparks to the base material joint 52.
  • the discharge tip 4 of the center electrode 2 is also composed of a discharge part 41 disposed on the spark discharge gap 11 side, a material having a melting point lower than that of the discharge part 41, and an electrode mother.
  • the base material joining portion 42 joined to the material 20 is composed of a composite material formed by joining together.
  • tip preparation process demonstrated in Example 1, the temporary joining process, and the main joining process are performed.
  • the discharge part 41 and the base material bonding part 42 are diffusion-bonded to obtain the discharge chip 4.
  • the discharge chip 4 is temporarily joined by resistance welding to the tip surface 21 of the electrode base material 20 of the center electrode 2 as shown in FIG. That is, the tip portion of the electrode base material 20 of the center electrode 2 before joining the discharge chip 4 has a substantially conical shape and has a flat surface whose tip is orthogonal to the axial direction.
  • the discharge chip 4 is temporarily bonded to the tip surface 21 which is a flat surface so that the base material bonding portion 42 side is brought into contact therewith.
  • the discharge tip 4 is joined to the electrode base material 20 by laser welding.
  • a melting portion 422 between the base material joint portion 42 of the discharge chip 4 and the electrode base material 20 is formed in an annular shape.
  • angular part 421 (FIG. 8) of the base material junction part 42 is removed geometrically as shown in FIG. 9, and the side surface 411 of the discharge part 41 and the surface (substantially conical part) of the electrode base material 20 are removed.
  • the connecting surface 423 is formed to smoothly connect the side surface 22).
  • the connection surface 423 has a shape in which a cross section of a plane passing through the central axis of the discharge chip 5 smoothly connects a curve and a straight line, and does not have a sharp edge.
  • Example 1 Others are the same as in Example 1.
  • the same reference numerals as those used in the first embodiment denote the same components as in the first embodiment unless otherwise specified.
  • the center electrode has the same configuration as that of the second embodiment, and the discharge tip of the ground electrode is made of a metal tip that is not a composite material, or the discharge tip is not provided on the ground electrode. You can also.

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  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Spark Plugs (AREA)

Abstract

La présente invention concerne un procédé de production d'une bougie d'allumage (1), une électrode (2) centrale ou une électrode (3) de masse étant dotée d'une puce (5) de décharge. Selon le procédé de production de puce, la puce (5) de décharge est produite par liaison l'un à l'autre d'une partie (51) de décharge disposée sur un côté d'espace (11) de décharge d'étincelles et un joint (52) en matériau de base, constitué d'un matériau ayant un point de fusion inférieur au point de fusion de la partie (51) de décharge et lié à un matériau (30) de base d'électrode. Selon le procédé de liaison temporaire, la puce (5) de décharge est temporairement liée au matériau (30) de base d'électrode sur le joint (52) en matériau de base par soudage par résistance. Selon le procédé de liaison à proprement parler, la puce (5) de décharge est liée au matériau (30) de base d'électrode par soudage laser, afin que la surface (511) latérale de la partie (51) de décharge et la surface (31) du matériau (30) de base d'électrode puissent être liées de manière uniforme l'une à l'autre par une surface (523) de liaison n'ayant aucun bord pointu.
PCT/JP2014/063507 2013-05-21 2014-05-21 Procédé de production de bougie d'allumage pour moteur à combustion interne WO2014189088A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
CN201480028953.7A CN105247747B (zh) 2013-05-21 2014-05-21 内燃机用的火花塞的制造方法
EP14801406.1A EP3001519B1 (fr) 2013-05-21 2014-05-21 Procédé de production de bougie d'allumage pour moteur à combustion interne

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2013106942A JP6043681B2 (ja) 2013-05-21 2013-05-21 内燃機関用のスパークプラグの製造方法
JP2013-106942 2013-05-21

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WO2014189088A1 true WO2014189088A1 (fr) 2014-11-27

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Cited By (1)

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CN105807589A (zh) * 2015-01-16 2016-07-27 富士施乐株式会社 管状体、管状体单元、图像形成装置及管状体的制造方法

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Publication number Priority date Publication date Assignee Title
JP6702094B2 (ja) 2016-08-31 2020-05-27 株式会社デンソー スパークプラグ
JP6944429B2 (ja) 2018-11-09 2021-10-06 日本特殊陶業株式会社 スパークプラグ

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JP2008077838A (ja) * 2006-09-18 2008-04-03 Denso Corp 内燃機関用のスパークプラグ及びその製造方法
JP2009533803A (ja) * 2006-04-07 2009-09-17 フェデラル−モーグル コーポレイション スパークプラグ
WO2013015262A1 (fr) 2011-07-28 2013-01-31 田中貴金属工業株式会社 Électrode à gainage pour bougie d'allumage et procédé de fabrication associé

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CN101529678B (zh) * 2005-11-18 2012-10-10 费德罗—莫格尔公司 形成具有多层点火尖端的火花塞的方法
US7521850B2 (en) * 2005-11-18 2009-04-21 Federal Mogul World Wide, Inc. Spark plug with multi-layer firing tip
CN101670488A (zh) * 2009-02-05 2010-03-17 株洲湘火炬火花塞有限责任公司 一种贵金属火花塞电极的激光焊接方法

Patent Citations (3)

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Publication number Priority date Publication date Assignee Title
JP2009533803A (ja) * 2006-04-07 2009-09-17 フェデラル−モーグル コーポレイション スパークプラグ
JP2008077838A (ja) * 2006-09-18 2008-04-03 Denso Corp 内燃機関用のスパークプラグ及びその製造方法
WO2013015262A1 (fr) 2011-07-28 2013-01-31 田中貴金属工業株式会社 Électrode à gainage pour bougie d'allumage et procédé de fabrication associé

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105807589A (zh) * 2015-01-16 2016-07-27 富士施乐株式会社 管状体、管状体单元、图像形成装置及管状体的制造方法
CN105807589B (zh) * 2015-01-16 2018-12-18 富士施乐株式会社 管状体、管状体单元、图像形成装置及管状体的制造方法

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Publication number Publication date
JP6043681B2 (ja) 2016-12-14
EP3001519A4 (fr) 2017-01-25
JP2014229429A (ja) 2014-12-08
EP3001519B1 (fr) 2019-05-01
CN105247747B (zh) 2017-08-29
EP3001519A8 (fr) 2016-08-10
EP3001519A1 (fr) 2016-03-30
CN105247747A (zh) 2016-01-13

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