JPH0375994B2 - - Google Patents
Info
- Publication number
- JPH0375994B2 JPH0375994B2 JP56015430A JP1543081A JPH0375994B2 JP H0375994 B2 JPH0375994 B2 JP H0375994B2 JP 56015430 A JP56015430 A JP 56015430A JP 1543081 A JP1543081 A JP 1543081A JP H0375994 B2 JPH0375994 B2 JP H0375994B2
- Authority
- JP
- Japan
- Prior art keywords
- electrode
- noble metal
- metal plate
- center electrode
- diameter portion
- Prior art date
- Legal status (The legal status 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 status listed.)
- Expired - Lifetime
Links
- 229910000510 noble metal Inorganic materials 0.000 claims description 39
- 238000002485 combustion reaction Methods 0.000 claims description 6
- 239000012212 insulator Substances 0.000 claims description 4
- 230000002093 peripheral effect Effects 0.000 claims 1
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 14
- 239000010970 precious metal Substances 0.000 description 14
- 238000003466 welding Methods 0.000 description 12
- 229910052697 platinum Inorganic materials 0.000 description 7
- 229910045601 alloy Inorganic materials 0.000 description 3
- 239000000956 alloy Substances 0.000 description 3
- 238000002788 crimping Methods 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 description 2
- 229910052804 chromium Inorganic materials 0.000 description 2
- 238000005260 corrosion Methods 0.000 description 2
- 230000007797 corrosion Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 229910052741 iridium Inorganic materials 0.000 description 2
- GKOZUEZYRPOHIO-UHFFFAOYSA-N iridium atom Chemical compound [Ir] GKOZUEZYRPOHIO-UHFFFAOYSA-N 0.000 description 2
- 238000005304 joining Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- -1 Of course Chemical compound 0.000 description 1
- 239000010953 base metal Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 229910052737 gold Inorganic materials 0.000 description 1
- 239000010931 gold Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 229910052763 palladium Inorganic materials 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 229910052703 rhodium Inorganic materials 0.000 description 1
- 239000010948 rhodium Substances 0.000 description 1
- MHOVAHRLVXNVSD-UHFFFAOYSA-N rhodium atom Chemical compound [Rh] MHOVAHRLVXNVSD-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Spark Plugs (AREA)
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は耐消耗性を向上させた内燃機関用スパ
ークプラグ（以下スパークプラグと呼ぶ）に関す
るものである。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a spark plug for an internal combustion engine (hereinafter referred to as a spark plug) with improved wear resistance.
従来公知の貴金属チツプを有するスパークプラ
グは、第１，２図に示すように貴金属チツプ５を
加締め後、抵抗溶接を行うか、第３図の如く単に
通常の抵抗溶接を行うという方法で、貴金属チツ
プが中心電極３もしくは接地電極４に固定されて
いる。
Conventionally known spark plugs with noble metal tips are manufactured by crimping the noble metal tip 5 as shown in FIGS. 1 and 2 and then performing resistance welding, or by simply performing ordinary resistance welding as shown in FIG. A noble metal chip is fixed to the center electrode 3 or the ground electrode 4.
しかし、前記従来の構成では、次のような問題
がある。即ち、
(1) 貴金属をチツプ状にして加締めるため、貴金
属量が多くなり、非常にコストアツプとなる。 However, the conventional configuration has the following problems. That is, (1) Since the precious metal is made into chips and crimped, the amount of precious metal increases, resulting in a significant increase in cost.
(2) 加締め後、抵抗溶接を実施する方法は、加締
める必要があるために凹部３ｂを作るなど構造
が複雑となり、特に接地電極４で加締め形状を
作るのは非常に困難であり、量産する上で非常
に問題がある。(2) The method of performing resistance welding after crimping requires crimping, which results in a complicated structure such as creating a recess 3b, and it is particularly difficult to create a crimped shape using the ground electrode 4. There are serious problems in mass production.
(3) 単に抵抗溶接を行う方法では溶接後の信頼性
が問題となる。(3) Mere resistance welding poses a problem in reliability after welding.
そこで、従来では仏国第1435473号明細書に開
示されるように、白金ロツドを高周波炉により溶
融させた中心電極に挿入することにより、中心電
極の端面に円錐ヘツドが形成され、この円錐ヘツ
ドにより、強固に白金ロツドが中心電極内に固定
することが行なわれてきた。 Therefore, conventionally, as disclosed in FR No. 1435473, a platinum rod is inserted into a center electrode melted in a high frequency furnace to form a conical head on the end face of the center electrode. The platinum rod has been firmly fixed within the center electrode.
しかし、このような構成では白金ロツドを使用
するために、非常に高価なプラグとなつてしまう
という問題が生じる。
However, since such a configuration uses a platinum rod, a problem arises in that the plug becomes very expensive.
そこで、本発明は貴金属チツプをプレート状に
なして貴金属の大きさを小さくできたにもかかわ
らず、容易に貴金属プレートを電極に強固に固定
可能とさせることを目的とするものである。 Therefore, an object of the present invention is to make the noble metal chip into a plate shape so that the size of the noble metal can be reduced and yet the noble metal plate can be easily and firmly fixed to the electrode.
内燃機関用スパークプラグにおいて、中心電極
の径小部または中心電極の径小部に対向する接地
電極のいずれか一方に設置され、他方の電極に対
向する平面部を有する偏平形状の貴金属プレート
と、一方の電極に貴金属プレートを固定するよう
に、該電極に形成され、かつ貴金属プレートの平
面部の全外周に形成される盛り上がり部とからな
る内燃機関用スパークプラグを提供するものであ
る。
In a spark plug for an internal combustion engine, a flat noble metal plate installed on either a small diameter portion of a center electrode or a ground electrode facing the small diameter portion of the center electrode and having a flat portion facing the other electrode; A spark plug for an internal combustion engine is provided, which includes a raised part formed on one electrode so as to fix the noble metal plate to the electrode, and formed on the entire outer periphery of a plane part of the noble metal plate.
本発明では、上記構成とすることにより、貴金
属プレートの電極への固定の際、貴金属プレート
の平面部を全周より盛り上がり部によつて固定す
ることができるので、偏平形状の貴金属プレート
であつても確実に電極に固定することができる。
In the present invention, with the above configuration, when fixing the noble metal plate to the electrode, the flat part of the noble metal plate can be fixed by the raised part from the entire circumference, so that even if the noble metal plate is a flat noble metal plate, can also be securely fixed to the electrode.
以下本発明を具体的実施例により詳細に説明す
る。
The present invention will be explained in detail below using specific examples.
第４図は、本発明のスパークプラグの先端断面
図を示す。 FIG. 4 shows a sectional view of the tip of the spark plug of the present invention.
３は、本発明のスパークプラグの中心電極であ
り、通常のスパークプラグに適用されているNi
にCr、Fe等が添加された耐熱耐食性に優れた従
来周知のNi基合金よりなり、絶縁碍子２の軸穴
２ａに封入されている。そして、中心電極３の先
端部には、この中心電極３の胴部３ａよりも径の
小なる径小部３ｂが形成され、この径小部３ｂの
先端面において、直径0.7mm〜1.0mmの厚さ0.1mm〜
0.4mm程度の偏平形状をなし、例えば白金よりな
る貴金属プレート５が、中心電極３の径小部３ｂ
との接触面からはみ出すことなく抵抗溶接によつ
て固定されている。 3 is the center electrode of the spark plug of the present invention, which is made of Ni which is applied to ordinary spark plugs.
It is made of a conventionally well-known Ni-based alloy with excellent heat and corrosion resistance to which Cr, Fe, etc. are added, and is sealed in the shaft hole 2a of the insulator 2. A small-diameter portion 3b smaller in diameter than the body portion 3a of the center electrode 3 is formed at the tip of the center electrode 3, and the tip surface of the small-diameter portion 3b has a diameter of 0.7 mm to 1.0 mm. Thickness 0.1mm~
A noble metal plate 5 made of, for example, platinum and having a flat shape of about 0.4 mm is attached to the small diameter portion 3b of the center electrode 3.
It is fixed by resistance welding without protruding from the contact surface.
また、ハウジング１には、中心電極３と同様、
通常のスパークプラグに適用されているNiにCr、
Fe等が添加された耐熱耐食性に優れた従来周知
のNi基合金よりなる接地電極４が溶接されてお
り、この接地電極４のうち中心電極３の貴金属プ
レート５との対設部分には、偏平形状をなす例え
ば白金よりなる貴金属プレート６が接地電極４と
の接触面からはみ出さない範囲内において、抵抗
溶接により固定されている。 In addition, the housing 1 includes, as well as the center electrode 3,
Cr, Ni applied to regular spark plugs,
A ground electrode 4 made of a conventionally well-known Ni-based alloy with excellent heat and corrosion resistance to which Fe etc. are added is welded. A shaped noble metal plate 6 made of, for example, platinum is fixed by resistance welding within a range that does not protrude from the contact surface with the ground electrode 4.
つまり、本実施例においては、各電極３，４の
貴金属プレート５，６の平面部５ａ，６ａが対向
するように固定されている。 That is, in this embodiment, the flat parts 5a and 6a of the noble metal plates 5 and 6 of each electrode 3 and 4 are fixed so as to face each other.
次に、この両貴金属プレート５，６の対設部分
の拡大図を第５図に、又第５図のＡ−Ａ断面図を
第６図に示す。 Next, FIG. 5 shows an enlarged view of the opposing portions of both noble metal plates 5 and 6, and FIG. 6 shows a cross-sectional view taken along line AA in FIG.
この第５図乃至第６図から明らかなように、本
発明のスパークプラグでは、抵抗溶接による電極
３，４の素材の盛り上がり部３ｃ，４ａが、各貴
金属プレート５，６の平面の平面部５ａ，６ａの
全周にわたり形成されるとともに、この盛り上が
り部３ｃ，４ａが各貴金属プレート５，６の約1/
２の高さにまで盛り上がつており、この盛り上が
り部３ｃ，４ａで各貴金属プレート５，６は確実
に中心電極３の径小部３ｂおよび接地電極４に固
定されている。 As is clear from FIGS. 5 and 6, in the spark plug of the present invention, the raised portions 3c, 4a of the material of the electrodes 3, 4 formed by resistance welding are the flat portions 5a of the planar surfaces of the noble metal plates 5, 6. , 6a, and the raised portions 3c, 4a cover approximately 1/1/2 of each precious metal plate 5, 6.
The noble metal plates 5 and 6 are securely fixed to the small diameter portion 3b of the center electrode 3 and the ground electrode 4 by the raised portions 3c and 4a.
次に、本発明のスパークプラグの各電極３，４
への貴金属プレート５，６の接合方法を詳述す
る。 Next, each electrode 3, 4 of the spark plug of the present invention
The method of joining the precious metal plates 5 and 6 to the metal plates will be described in detail.
はじめに、中心電極３の径小部３ｂの先端面に
貴金属プレート５を接合する際には、この径小部
３ｂの先端部に貴金属プレート５を載せ、抵抗溶
接に用いる図示しない電極を中心電極３および貴
金属プレート５のそれぞれに接続させる。そし
て、この電極間に電流を流すことによつて、中心
電極３と貴金属プレート５との間に接触抵抗によ
る、抵抗熱を生じせしめ、この熱を利用すること
によつて、中心電極３の径小部３ｂの母材の一部
を軟化させるとともに、貴金属プレート５を径小
部３ｂに対して加圧することにより、貴金属プレ
ート５が、径小部３ｂに埋没することによつて上
記盛り上がり部３ｃが形成されるのである。 First, when joining the noble metal plate 5 to the tip end surface of the small diameter portion 3b of the center electrode 3, place the noble metal plate 5 on the tip of the small diameter portion 3b, and attach the electrode (not shown) used for resistance welding to the center electrode 3. and the noble metal plate 5, respectively. By passing a current between the electrodes, resistance heat is generated between the center electrode 3 and the noble metal plate 5 due to contact resistance, and by using this heat, the diameter of the center electrode 3 is By softening a part of the base material of the small portion 3b and pressurizing the noble metal plate 5 against the small diameter portion 3b, the noble metal plate 5 is buried in the small diameter portion 3b, thereby forming the raised portion 3c. is formed.
この時、本実施例では、加圧力を14Kg、電流を
800A、通電時間を５サイクルとした。 At this time, in this example, the pressing force is 14Kg and the current is
800A, energizing time was 5 cycles.
また、接地電極４では、中心電極３の径小部３
ｂに接合された貴金属プレート５に対設する位置
に貴金属プレート６を載せ、中心電極３に貴金属
プレート５を接合した時と同一条件にて、接地電
極４には貴金属プレート６を固定した。 In addition, in the ground electrode 4, the small diameter portion 3 of the center electrode 3
A noble metal plate 6 was placed at a position opposite to the noble metal plate 5 bonded to b, and the noble metal plate 6 was fixed to the ground electrode 4 under the same conditions as when the noble metal plate 5 was bonded to the center electrode 3.
以上のように、各電極３，４と各貴金属プレー
ト５，６との間に、抵抗溶接により生じる抵抗熱
を生じさせ、この抵抗熱によつて、各電極３，４
と各貴金属プレート５，６との間が軟化されると
ともに、各貴金属プレート５，６をこの軟化した
部分に対して加圧を行い、各貴金属プレート５，
６の平面部５ａ，６ａの全周にわたり盛り上がり
部３ｃ，４ａを形成するのである。 As described above, resistance heat generated by resistance welding is generated between each electrode 3, 4 and each noble metal plate 5, 6, and by this resistance heat, each electrode 3, 4
and each noble metal plate 5, 6 is softened, and each noble metal plate 5, 6 is pressurized against this softened portion, and each noble metal plate 5, 6 is softened.
The raised portions 3c and 4a are formed over the entire circumference of the flat portions 5a and 6a of No.6.
上記実施例によれば、中心電極３の先端に形成
された径小部３ｂのように、先端端面の面積の小
さなところにも、接合面がはみ出すことなく接合
可能な小さな貴金属プレート５，６であつても、
溶接盛り上がり部３ｃ，４ａにより全周にわたつ
て加締められた構造となつているため、外力によ
る側面からの貴金属プレート５，６の剥離が防止
され、また中心電極３および接地電極４の母材金
属と貴金属プレート５および６との線膨張係数の
違いのための冷熱サイクル繰り返しによる貴金属
プレート５，６が剥離するのを防止できる。 According to the embodiment described above, the small precious metal plates 5 and 6 can be bonded to a small area of the tip end surface, such as the small diameter portion 3b formed at the tip of the center electrode 3, without the bonding surface protruding. Even if
Since the welding bulges 3c and 4a are crimped around the entire circumference, the precious metal plates 5 and 6 are prevented from peeling off from the side surfaces due to external force, and the base metals of the center electrode 3 and ground electrode 4 are It is possible to prevent the noble metal plates 5 and 6 from peeling off due to repeated cooling and heating cycles due to the difference in linear expansion coefficient between the metal and the noble metal plates 5 and 6.
さらにまた、白金にイリジウムを添加すると硬
度が増すので、上記溶接には適する。 Furthermore, since adding iridium to platinum increases its hardness, it is suitable for the above-mentioned welding.
本発明は上記の実施例に限定されず、以下のご
とく数々の変形が可能である。 The present invention is not limited to the embodiments described above, but can be modified in many ways as described below.
(1) 貴金属プレート５，６の材質は白金の他に、
パラジウム、イリジウム、ロジウム、金等、な
らびにこれらの合金でも勿論よい。(1) The material of the precious metal plates 5 and 6 is platinum,
Of course, palladium, iridium, rhodium, gold, etc., and alloys thereof may also be used.
(2) 貴金属プレート５，６の形状は円形、長方
形、星形状等、数々の形状が考えられる。(2) The precious metal plates 5 and 6 can have many shapes such as circular, rectangular, and star-shaped.
以下要するに本発明によれば、貴金属ロツドに
代えて、偏平形状の貴金属プレートを採用してい
るので、余分な貴金属量を極力少なくすることが
でき、従つて従来に比べて安価な内燃機関用スパ
ークプラグを提供できる。
In short, according to the present invention, since a flat precious metal plate is used instead of a precious metal rod, the amount of excess precious metal can be minimized, and the spark for internal combustion engines is therefore cheaper than the conventional one. We can provide plugs.
更に、各電極と各貴金属プレートの全周が電極
に確実に保持されるから、偏平形状の貴金属プレ
ートであつても、プレートを各電極に強固に固定
可能とさせ、剥離といつた問題を確実に回避する
ことができる。 Furthermore, since the entire circumference of each electrode and each precious metal plate is securely held on the electrode, even if the plate is a flat precious metal plate, the plate can be firmly fixed to each electrode, ensuring problems such as peeling. can be avoided.
第１図は従来のスパークプラグを示す断面図、
第２図は第１図の電極部の製造説明に供する正面
図、第３図は従来の他の例における電極部の正面
図、第４図は本発明の一実施例を示す断面図、第
５図は第４図の要部を拡大して示す断面図、第６
図は第５図のＡ−Ａ断面図である。
３……中心電極、３ａ……中心電極の胴部、３
ｂ……中心電極の径小部、３ｃ，４ａ……盛り上
がり部、４……接地電極、５，６……貴金属プレ
ート。
Figure 1 is a cross-sectional view of a conventional spark plug.
2 is a front view for explaining the manufacture of the electrode section shown in FIG. 1, FIG. 3 is a front view of another conventional electrode section, and FIG. 4 is a sectional view showing an embodiment of the present invention. Figure 5 is an enlarged sectional view of the main part of Figure 4;
The figure is a sectional view taken along the line AA in FIG. 3...center electrode, 3a...body of center electrode, 3
b... Small diameter portion of center electrode, 3c, 4a... Raised portion, 4... Ground electrode, 5, 6... Precious metal plate.
Claims (1)
い径小部が先端に形成された中心電極と、 前記絶縁碍子の外周面に固定されたハウジング
と、 このハウジングに設けられるとともに、前記中
心電極の前記径小部に対向した接地電極とからな
る内燃機関用スパークプラグであつて、 前記中心電極の前記径小部または前記中心電極
の前記径小部に対向する前記接地電極のいずれか
一方に設置され、他方の電極に対向する平面部を
有する偏平形状の貴金属プレートと、 前記一方の電極に前記貴金属プレートを固定す
るように、該電極に形成され、かつ前記貴金属プ
レートの前記平面部の全外周に形成される盛り上
がり部と、 からなることを特徴とする内燃機関用スパークプ
ラグ。[Scope of Claims] 1. An insulator, a center electrode held by the insulator and having a small diameter portion at its tip that is smaller in diameter than the body, and a housing fixed to the outer peripheral surface of the insulator. , a spark plug for an internal combustion engine comprising a ground electrode provided in the housing and facing the small diameter portion of the center electrode, the small diameter portion of the center electrode or the small diameter portion of the center electrode; a flat noble metal plate installed on one of the ground electrodes facing the other electrode and having a flat surface facing the other electrode; and a flat noble metal plate formed on the electrode so as to fix the noble metal plate to the one electrode. A spark plug for an internal combustion engine, comprising: and a raised portion formed on the entire outer periphery of the flat portion of the noble metal plate.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1543081A JPS57130385A (en) | 1981-02-04 | 1981-02-04 | Spark plug for internal combustion engine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1543081A JPS57130385A (en) | 1981-02-04 | 1981-02-04 | Spark plug for internal combustion engine |
Related Child Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4258101A Division JP2513173B2 (en) | 1992-09-28 | 1992-09-28 | Method for manufacturing spark plug for internal combustion engine |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS57130385A JPS57130385A (en) | 1982-08-12 |
| JPH0375994B2 true JPH0375994B2 (en) | 1991-12-04 |
Family
ID=11888561
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1543081A Granted JPS57130385A (en) | 1981-02-04 | 1981-02-04 | Spark plug for internal combustion engine |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS57130385A (en) |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3301094B2 (en) * | 1991-12-13 | 2002-07-15 | 株式会社デンソー | Spark plug for internal combustion engine and method of manufacturing the same |
| JP2513173B2 (en) * | 1992-09-28 | 1996-07-03 | 日本電装株式会社 | Method for manufacturing spark plug for internal combustion engine |
| JP3196601B2 (en) * | 1995-10-11 | 2001-08-06 | 株式会社デンソー | Method of manufacturing spark plug for internal combustion engine |
| DE102013105698B4 (en) | 2012-06-01 | 2019-05-02 | Federal-Mogul Ignition Company | spark plug |
| US9673593B2 (en) | 2012-08-09 | 2017-06-06 | Federal-Mogul Ignition Company | Spark plug having firing pad |
| US9318879B2 (en) | 2012-10-19 | 2016-04-19 | Federal-Mogul Ignition Company | Spark plug having firing pad |
| JP7028810B2 (en) * | 2019-01-25 | 2022-03-02 | 日本特殊陶業株式会社 | Spark plug |
| JP7121081B2 (en) * | 2020-08-19 | 2022-08-17 | 日本特殊陶業株式会社 | Spark plug |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2296033A (en) * | 1941-01-18 | 1942-09-15 | Gen Motors Corp | Spark plug |
| JPS522378A (en) * | 1975-06-24 | 1977-01-10 | Seiko Instr & Electronics Ltd | Semiconductor device manufacturing method |
-
1981
- 1981-02-04 JP JP1543081A patent/JPS57130385A/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2296033A (en) * | 1941-01-18 | 1942-09-15 | Gen Motors Corp | Spark plug |
| JPS522378A (en) * | 1975-06-24 | 1977-01-10 | Seiko Instr & Electronics Ltd | Semiconductor device manufacturing method |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS57130385A (en) | 1982-08-12 |
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