JP4051591B2

JP4051591B2 - Ignition coil

Info

Publication number: JP4051591B2
Application number: JP19434199A
Authority: JP
Inventors: 幸雄長谷; 有恒加藤
Original assignee: Denso Corp
Current assignee: Denso Corp
Priority date: 1999-07-08
Filing date: 1999-07-08
Publication date: 2008-02-27
Anticipated expiration: 2019-07-08
Also published as: JP2001023840A

Description

【０００１】
【発明の属する技術分野】
本発明は、内燃機関の点火装置に印加する高電圧を発生する点火コイルに関する。
【０００２】
【従来の技術】
近年、二輪・四輪車両に搭載される内燃機関の点火装置における点火コイルの小型化・軽量化や、搭載性向上の要求により、プラグ直結型の点火コイルが採用されており、特にプラグホール収納型の点火コイルが多く用いられている。点火コイルにより印加した高電圧が放電される際には、電波雑音が発生し、特にマイクロコンピュータを搭載する他の電装品等の作動に悪影響を及ぼすことがある。
【０００３】
【発明が解決しようとする課題】
プラグ直結型の点火コイルにおいては、電波雑音低減のための抵抗を内蔵した点火プラグを装着するように設計されている。抵抗入り点火プラグの標準の抵抗値は５ｋΩであるが、電波雑音をさらに低減するためには抵抗値をより大きくする必要がある。また、使用者が抵抗を内蔵しない点火プラグを誤って使用した場合に、電波雑音による誤動作の可能性が増大する。そのため、点火コイル内部に電波雑音防止のための抵抗を挿入することが考えられる。
【０００４】
点火コイル内部に電波雑音防止用の抵抗を挿入したものとして、実開昭６０−９８２８８号公報に開示されるものが知られている。しかしながら、実開昭６０−９８２８８号公報に開示される点火コイルでは、抵抗の固定方法が複雑で部品点数が増大し、製造コストが高くなるという問題があった。
本発明の目的は、簡単な構成で電波雑音を低減するための抵抗を固定することのできる点火コイルを提供することにある。
【０００５】
【課題を解決するための手段】
本発明の請求項１記載の点火コイルによると、二次コイルの巻線の一端を接続する端子部および筒状部を有する端子部材と、端子部材の筒状部に一端が収容される抵抗部材と、点火プラグに接続される接続部および抵抗部材の他端を収容する筒部を有する高圧ターミナルと、抵抗部材の少なくとも一方の端の外周に設けられ抵抗部材を保持する径方向の付勢力を加える複数の弾性手段とを備える。そのため、点火コイルより発生する電波雑音を低減するための抵抗部材を簡単な構成で固定することができる。
【０００９】
本発明の請求項４記載の点火コイルによると、抵抗部材と高圧ターミナルの筒部との間に、略円筒状に形成される筒状部と筒状部の内周に形成される複数の弾性突起とを有する第２の端子部材を備える。そのため、抵抗部材の他端側と高圧ターミナルとの寸法精度がそれほど高くなくても抵抗部材を安定して保持することができる。
【００１０】
本発明の請求項５または請求項６記載の点火コイルによると、抵抗部材はセラミックを基材とする略円筒状の抵抗部の両端に略椀状の電極部を被せてなる。そのため、一般に規格化された安価な抵抗部材を用いることができる。
【００１１】
本発明の請求項７記載の点火コイルによると、抵抗部材の電極部の外周に複数の弾性突起を有する。そのため、抵抗部材を部品点数の少ない簡単な構成で点火コイルに固定することができる。弾性突起の構成としては、電極部の側面を打ち出し加工して外側に突出させることや、切り起こし加工により板ばね部を形成することが可能である。
【００１２】
【発明の実施の形態】
以下、本発明の実施の形態を示す複数の実施例を図に基づいて説明する。
（第１実施例）
本発明の第１実施例による点火コイルを図１に示す。図１に示す点火コイル１０は、図示しないエンジンブロックの上部に気筒毎に形成された図示しないプラグホール内に収容され、点火装置としての点火プラグと図１の下側で電気的に接続する。
【００１３】
点火コイル１０は樹脂材料からなる略円筒状のケース１１およびケース１１の底部に一体形成され高電圧引き出しのタワー１２を備える。このケース１１およびタワー１２内に、コアとしての中心コア１３、中心コア１３の外周に設けられる一次ボビン１４、一次ボビンの外周に巻回される一次コイル１５、一次コイル１５の外周に設けられ外周側に突出した複数の鍔部１６１を有する二次ボビン１６、二次ボビン１６の外周に鍔部１６１により複数段に隔てられて巻回される二次コイル１７等が収容されている。ケース１１および高圧タワー１２内に各部材を収容した後にはエポキシ樹脂２０が充填され、点火コイル１０内の各部材間に浸透し、樹脂絶縁材として部材間の電気絶縁を確実なものとしている。
【００１４】
制御信号入力用のコネクタ２１はプラグホールから突出するようにコイルケース１１に設けられており、一次コイル１５および二次コイル１７のアース側と接続する端子２２が設けられている。
【００１５】
棒状の中心コア１３は薄い珪素鋼板を横断面がほぼ円形となるように径方向に積層して組立てられている。外装コア１８はケース１１の外側に装着されている。一次コイルの通電時に、中心コア１３と外装コア１８とにより磁気回路を形成する。外装コア１８の外側には、プラグホールへの放電を防止する樹脂製の外装ケース１９が設けられている。
【００１６】
ステンレス等の金属により形成される高圧ターミナル２３は高圧タワー１２に圧入されている。図２は高圧ターミナル２３を示す断面図であり、（Ａ）は（Ｂ）のＩ−Ｉ線に沿った軸方向断面図、（Ｂ）は（Ａ）のII−II線に沿った径方向断面図である。図２に示すように、高圧ターミナル２３の一端には、点火プラグを収容する収容部２３１とピン２４を保持するための溝２３２とが設けられる。湾曲させた複数のピン２４を溝２３２に差し込むことにより、点火プラグ３０との接続部が構成され、収容部２３１に収容された点火プラグ３０は、ピン２４の弾性力により保持され、高圧ターミナル２３と点火プラグ３０は電気的に接続される。図３は、点火コイル１０に点火プラグ３０を接続した状態を示す図である。高圧ターミナル２３の反点火プラグ３０側には、後述する抵抗部材２５の一端を収容する凹部２３３が形成されている。
【００１７】
二次ボビン１６の下端には、二次コイル１７の巻終わり線を巻き付けて、はんだ付けにより接続する端子部２６２と筒状部２６１とを備える端子部材としての二次ターミナル２６が圧入されている。二次ターミナル２６はりん青銅等の金属により形成される。
【００１８】
二次ターミナル２６と高圧ターミナル２３との間には、セラミックを基材とする略円筒状の抵抗部２５１の両端に金属製で略椀状の電極部２５２、２５３を被せてなり、点火プラグ３０の放電時の電波雑音を低減するための抵抗部材２５が設けられている。この形状の抵抗部材２５としては、一般に規格化された安価なものを用いることができるため、抵抗部材２５のコストを低減することができる。
【００１９】
以下に、本実施例において点火コイル１０に抵抗部材２５を固定するための構造を説明する。
図４の（Ａ）は二次ターミナル２６の平面図、（Ｂ）は（Ａ）のIII−III線断面図、（Ｃ）は左側面図である。
二次ターミナル２６の筒状部２６１は、金属の平板を曲げ加工して、断面が略三角形に形成される。筒状部２６１の３つの側面には、平面部分をコの字状に切り欠き、内側に切り起こし加工し、弾性変形可能な弾性突起としての板ばね部２６３が形成されている。筒状部２６１の側面に平面が形成されているため、板ばね部２６３の加工が容易となる。
【００２０】
抵抗部材２５の一方の電極部２５２は、二次ターミナル２６の筒状部２６１の内周に圧入され、複数の板ばね部２６３による径方向の付勢力によって保持される。これにより、二次ターミナル２６と抵抗部材２５は電気的に導通する。
【００２１】
抵抗部材２５の他方の電極部２５３は、高圧ターミナル２３の凹部２３３に収容される。電極部２５３と凹部２３３との導通を確実にするためには、電極部２５３を凹部２３３に圧入することも考えられるが、そのためには、電極部２５３と凹部２３３との寸法精度を極めて高くする必要があり、製造が困難である。そのため、本実施例では、電極部２５３と凹部２３３との間に第二の端子部材としての二次ターミナル２７を配設している。
【００２２】
図５の（Ａ）は二次ターミナル２７の平面図、（Ｂ）は（Ａ）のIV−IV線断面図、（Ｃ）は側面図である。二次ターミナル２７の筒状部２７１は、断面が略三角形に形成されている。筒状部２７１の３つの側面には、内側に切り起こし加工した弾性突起としての板ばね部２７２が形成されている。
【００２３】
二次ターミナル２７の筒状部２７１の外周が高圧ターミナル２３の凹部２３３の内周に圧入される。筒状部２７１の内周に抵抗部材２５の他端の電極部２５３が圧入され、複数の板ばね部２７２による径方向の付勢力によって保持される。そのため、電極部２５３の外径と凹部２３３の内径との寸法精度がそれほど高くなくても、電極部２５３を凹部２３３に圧入して固定することができる。従って、簡単な構成で抵抗部材２５を確実に組み付けることができ、抵抗部材２５を二次ターミナル２６および２７と導通させた状態でエポキシ樹脂２０を充填する作業が容易となる。
本実施例では、抵抗部材２５の両端に二次ターミナルを設けたが、本発明としては一方の二次ターミナルのみであってもよい。
【００２４】
（第２実施例）
本実施例の第２実施例による点火コイルを図６に示す。第１実施例と実質的に同一構成部分に同一符号を付し、説明を省略する。
第２実施例の点火コイルでは、図７に示す抵抗部材３５が二次ターミナル２６と高圧ターミナル２３との間に挿入されている。抵抗部材３５の抵抗部３５１の二次ターミナル２６側の端には、第１実施例と同様に略椀状の電極部３５２が被せられている。
【００２５】
図７の（Ａ）は抵抗部材３５の高圧ターミナル２３側の端を示す平面図であり、（Ｂ）は底面図である。抵抗部材３５の高圧ターミナル２３側の端に被せられる略椀状の電極部３５３には、電極部３５３を外側に打ち出し加工して形成された複数の弾性突起としての突出部３５４が設けられる。そのため、電極部３５３の外径と高圧ターミナル２３の凹部２３３の内径の寸法精度がそれほど高くなくても、電極部３５３を凹部２３３に圧入して固定することができるため、抵抗部材３５の組み付けが容易になる。
【００２６】
（第３実施例）
本実施例の第３実施例による点火コイルを図８に示す。第１、第２実施例と実質的に同一構成部分に同一符号を付し、説明を省略する。
第３実施例の点火コイルでは、抵抗部材４５が二次ターミナル２６と高圧ターミナル２３との間に挿入されている。抵抗部材４５の高圧ターミナル２３側の端に被せられる略椀状の電極部４５３には、電極部４５３の側面を外側に切り起こし加工して形成された複数の弾性突起としての板ばね部４５４が設けられる。第３実施例においても第２実施例と同様に、電極部４５３を凹部２３３に圧入して固定することができるため、抵抗部材４５の組み付けが容易になる。
【００２７】
以上、複数の実施例により説明したように、本発明によれば、電波雑音を低減するための抵抗を簡単な構成で確実に固定することができる。そのため、点火コイルに印加した高電圧が放電されるときに発生する電波雑音を低減することができる。また、抵抗を内蔵しない点火プラグを接続した場合であっても、電波雑音を小さくすることができる。
【００２８】
上述の複数の実施例では、二次ターミナルの断面を三角形状に形成したが、本発明としては、四角形以上の多角形や、円形など、他の形状であっても同様の効果を有する。
また、第２、第３実施例では、抵抗部材の高圧ターミナル側の電極部外周に弾性突起を設けたが、弾性突起を二次ターミナル側の電極部に設けてもよく、また、抵抗部材両端の電極部に弾性突起を設けてもよい。
【図面の簡単な説明】
【図１】本発明の第１実施例による点火コイルを示す断面図である。
【図２】本発明の第１実施例による点火コイルの高圧ターミナルを示す図である。
【図３】本発明の第１実施例による点火コイルと点火プラグを接続した状態を示す図である。
【図４】本発明の第１実施例による点火コイルの二次ターミナルを示す図である。
【図５】本発明の第１実施例による点火コイルの二次ターミナルを示す図である。
【図６】本発明の第２実施例による点火コイルを示す断面図である。
【図７】本発明の第２実施例による点火コイルの抵抗部材を示す図である。
【図８】本発明の第３実施例による点火コイルを示す断面図である。
【符号の説明】
１０点火コイル
１１ケース
１２タワー
１３中心コア（コア）
１５一次コイル
１６二次ボビン
１７二次コイル
２１コネクタ
２２端子
２３高圧ターミナル
２３３凹部
２５抵抗部材
２５１抵抗部
２５２、２５３電極部
２６二次ターミナル（端子部材）
２６１筒状部
２６２端子部
２６３板ばね部（弾性突起）
２７二次ターミナル（第２の端子部材）
２７１筒状部
２７２板ばね部（弾性突起）[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an ignition coil that generates a high voltage to be applied to an ignition device of an internal combustion engine.
[0002]
[Prior art]
In recent years, due to demands for smaller and lighter ignition coils in internal combustion engine ignition devices mounted on two-wheeled and four-wheeled vehicles, and demands for improved mountability, plug-connected ignition coils have been adopted, especially plug hole storage Many types of ignition coils are used. When the high voltage applied by the ignition coil is discharged, radio noise is generated, which may adversely affect the operation of other electrical components equipped with a microcomputer.
[0003]
[Problems to be solved by the invention]
The plug directly connected ignition coil is designed to be equipped with a spark plug with a built-in resistor for reducing radio noise. The standard resistance value of the spark plug with resistance is 5 kΩ, but it is necessary to increase the resistance value in order to further reduce radio noise. In addition, when a user accidentally uses a spark plug that does not incorporate a resistor, the possibility of malfunction due to radio noise increases. Therefore, it is conceivable to insert a resistor for preventing radio noise inside the ignition coil.
[0004]
As disclosed in Japanese Utility Model Laid-Open No. 60-98288, a resistor for preventing radio noise is inserted inside an ignition coil. However, the ignition coil disclosed in Japanese Utility Model Laid-Open No. 60-98288 has a problem that the method of fixing the resistance is complicated, the number of parts is increased, and the manufacturing cost is increased.
An object of the present invention is to provide an ignition coil capable of fixing a resistor for reducing radio noise with a simple configuration.
[0005]
[Means for Solving the Problems]
According to the ignition coil of the first aspect of the present invention, a terminal member having a terminal part and a cylindrical part for connecting one end of the winding of the secondary coil, and a resistance member having one end accommodated in the cylindrical part of the terminal member A high voltage terminal having a connecting portion connected to the spark plug and a cylindrical portion that accommodates the other end of the resistance member, and a radial biasing force that is provided on the outer periphery of at least one end of the resistance member and holds the resistance member A plurality of elastic means to be added. Therefore, the resistance member for reducing the radio noise generated from the ignition coil can be fixed with a simple configuration.
[0009]
According to the ignition coil of the fourth aspect of the present invention, the cylindrical portion formed in a substantially cylindrical shape between the resistance member and the cylindrical portion of the high-voltage terminal, and a plurality of elasticity formed on the inner periphery of the cylindrical portion. A second terminal member having a protrusion; Therefore, even if the dimensional accuracy between the other end side of the resistance member and the high voltage terminal is not so high, the resistance member can be stably held.
[0010]
According to the ignition coil of the fifth or sixth aspect of the present invention, the resistance member is formed by covering the both ends of a substantially cylindrical resistance portion made of ceramic as a base with substantially bowl-shaped electrode portions. Therefore, it is possible to use an inexpensive resistance member that is generally standardized.
[0011]
According to the ignition coil of the seventh aspect of the present invention, the plurality of elastic protrusions are provided on the outer periphery of the electrode portion of the resistance member. Therefore, the resistance member can be fixed to the ignition coil with a simple configuration with a small number of parts. As the configuration of the elastic protrusion, the side surface of the electrode portion can be stamped and protruded outward, or the leaf spring portion can be formed by cutting and raising.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a plurality of examples showing embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
An ignition coil according to a first embodiment of the present invention is shown in FIG. The ignition coil 10 shown in FIG. 1 is accommodated in a plug hole (not shown) formed for each cylinder in an upper part of an engine block (not shown), and is electrically connected to a spark plug as an ignition device on the lower side of FIG.
[0013]
The ignition coil 10 includes a substantially cylindrical case 11 made of a resin material and a tower 12 that is integrally formed at the bottom of the case 11 and draws out a high voltage. In the case 11 and the tower 12, a central core 13 as a core, a primary bobbin 14 provided on the outer periphery of the central core 13, a primary coil 15 wound around the outer periphery of the primary bobbin, an outer periphery provided on the outer periphery of the primary coil 15 A secondary bobbin 16 having a plurality of flanges 161 projecting to the side, and a secondary coil 17 wound around the outer periphery of the secondary bobbin 16 in a plurality of stages by the flanges 161 are accommodated. After the respective members are accommodated in the case 11 and the high-voltage tower 12, the epoxy resin 20 is filled and penetrates between the respective members in the ignition coil 10 to ensure electrical insulation between the members as a resin insulating material.
[0014]
The control signal input connector 21 is provided on the coil case 11 so as to protrude from the plug hole, and a terminal 22 connected to the ground side of the primary coil 15 and the secondary coil 17 is provided.
[0015]
The rod-shaped central core 13 is assembled by laminating thin silicon steel plates in the radial direction so that the cross section is substantially circular. The exterior core 18 is attached to the outside of the case 11. When the primary coil is energized, the central core 13 and the outer core 18 form a magnetic circuit. A resin exterior case 19 that prevents discharge to the plug hole is provided outside the exterior core 18.
[0016]
A high-pressure terminal 23 formed of a metal such as stainless steel is press-fitted into the high-pressure tower 12. 2A and 2B are cross-sectional views showing the high-voltage terminal 23, wherein FIG. 2A is an axial cross-sectional view taken along line II in FIG. 2B, and FIG. 2B is a radial direction taken along line II-II in FIG. It is sectional drawing. As shown in FIG. 2, at one end of the high-voltage terminal 23, a housing portion 231 that houses the spark plug and a groove 232 that holds the pin 24 are provided. By inserting a plurality of curved pins 24 into the groove 232, a connection portion with the spark plug 30 is configured, and the spark plug 30 housed in the housing portion 231 is held by the elastic force of the pin 24, and is connected to the high-pressure terminal 23. And the spark plug 30 are electrically connected. FIG. 3 is a view showing a state in which the ignition plug 30 is connected to the ignition coil 10. On the side of the anti-ignition plug 30 of the high-voltage terminal 23, a recess 233 that accommodates one end of a resistance member 25 described later is formed.
[0017]
At the lower end of the secondary bobbin 16, a secondary terminal 26 is press-fitted as a terminal member having a terminal portion 262 and a cylindrical portion 261 that are connected by soldering by winding a winding end line of the secondary coil 17. . The secondary terminal 26 is formed of a metal such as phosphor bronze.
[0018]
Between the secondary terminal 26 and the high-voltage terminal 23, both ends of a substantially cylindrical resistance portion 251 made of ceramic are covered with metal substantially saddle-shaped electrode portions 252 and 253. A resistance member 25 is provided to reduce radio noise during the discharge. As the resistance member 25 having this shape, a standardized and inexpensive one can be used, so that the cost of the resistance member 25 can be reduced.
[0019]
Below, the structure for fixing the resistance member 25 to the ignition coil 10 in a present Example is demonstrated.
4A is a plan view of the secondary terminal 26, FIG. 4B is a sectional view taken along line III-III in FIG. 4A, and FIG. 4C is a left side view thereof.
The cylindrical portion 261 of the secondary terminal 26 is formed by bending a metal flat plate to have a substantially triangular cross section. On the three side surfaces of the cylindrical portion 261, a plate spring portion 263 is formed as an elastic protrusion that can be elastically deformed by cutting a flat portion into a U-shape and cutting and raising the flat portion inward. Since a flat surface is formed on the side surface of the cylindrical portion 261, the processing of the leaf spring portion 263 is facilitated.
[0020]
One electrode portion 252 of the resistance member 25 is press-fitted into the inner periphery of the cylindrical portion 261 of the secondary terminal 26 and is held by a radial urging force by the plurality of leaf spring portions 263. Thereby, the secondary terminal 26 and the resistance member 25 are electrically connected.
[0021]
The other electrode portion 253 of the resistance member 25 is accommodated in the recess 233 of the high-voltage terminal 23. In order to ensure the electrical connection between the electrode part 253 and the recess 233, it is conceivable to press-fit the electrode part 253 into the recess 233. To that end, the dimensional accuracy between the electrode part 253 and the recess 233 is extremely increased. It is necessary and difficult to manufacture. Therefore, in this embodiment, the secondary terminal 27 as the second terminal member is disposed between the electrode portion 253 and the recess 233.
[0022]
5A is a plan view of the secondary terminal 27, FIG. 5B is a sectional view taken along line IV-IV in FIG. 5A, and FIG. 5C is a side view. The cylindrical part 271 of the secondary terminal 27 has a substantially triangular cross section. On the three side surfaces of the cylindrical portion 271, leaf spring portions 272 are formed as elastic protrusions cut and raised inward.
[0023]
The outer periphery of the cylindrical portion 271 of the secondary terminal 27 is press-fitted into the inner periphery of the recess 233 of the high-pressure terminal 23. The electrode portion 253 at the other end of the resistance member 25 is press-fitted into the inner periphery of the cylindrical portion 271 and is held by a radial urging force by the plurality of leaf spring portions 272. Therefore, even if the dimensional accuracy between the outer diameter of the electrode portion 253 and the inner diameter of the recess 233 is not so high, the electrode portion 253 can be press-fitted into the recess 233 and fixed. Therefore, the resistance member 25 can be reliably assembled with a simple configuration, and the work of filling the epoxy resin 20 in a state where the resistance member 25 is electrically connected to the secondary terminals 26 and 27 becomes easy.
In this embodiment, the secondary terminals are provided at both ends of the resistance member 25. However, only one secondary terminal may be used in the present invention.
[0024]
(Second embodiment)
The ignition coil according to the second embodiment of the present embodiment is shown in FIG. Components that are substantially the same as those of the first embodiment are denoted by the same reference numerals, and description thereof is omitted.
In the ignition coil according to the second embodiment, a resistance member 35 shown in FIG. 7 is inserted between the secondary terminal 26 and the high voltage terminal 23. A substantially bowl-shaped electrode portion 352 is placed on the end of the resistance portion 351 of the resistance member 35 on the secondary terminal 26 side, as in the first embodiment.
[0025]
7A is a plan view showing an end of the resistance member 35 on the high voltage terminal 23 side, and FIG. 7B is a bottom view. The substantially bowl-shaped electrode part 353 that covers the end of the resistance member 35 on the high-voltage terminal 23 side is provided with a plurality of protrusions 354 as elastic protrusions formed by stamping the electrode part 353 outward. Therefore, even if the dimensional accuracy of the outer diameter of the electrode portion 353 and the inner diameter of the concave portion 233 of the high-voltage terminal 23 is not so high, the electrode portion 353 can be press-fitted into the concave portion 233 and fixed. It becomes easy.
[0026]
(Third embodiment)
An ignition coil according to a third embodiment of the present embodiment is shown in FIG. Components that are substantially the same as those in the first and second embodiments are denoted by the same reference numerals, and description thereof is omitted.
In the ignition coil of the third embodiment, a resistance member 45 is inserted between the secondary terminal 26 and the high-voltage terminal 23. The substantially hook-shaped electrode portion 453 that covers the end of the resistance member 45 on the high-voltage terminal 23 side has a plurality of plate spring portions 454 as elastic protrusions formed by cutting and raising the side surface of the electrode portion 453 outward. Provided. In the third embodiment, as in the second embodiment, the electrode portion 453 can be press-fitted and fixed in the recess 233, so that the resistance member 45 can be easily assembled.
[0027]
As described above with reference to a plurality of embodiments, according to the present invention, it is possible to reliably fix a resistor for reducing radio noise with a simple configuration. Therefore, radio noise generated when the high voltage applied to the ignition coil is discharged can be reduced. Further, even when a spark plug that does not incorporate a resistor is connected, radio noise can be reduced.
[0028]
In the above-described embodiments, the secondary terminal has a triangular cross section. However, the present invention has the same effect even in other shapes such as a quadrilateral or more polygon or a circle.
In the second and third embodiments, the elastic protrusion is provided on the outer periphery of the electrode portion on the high-voltage terminal side of the resistance member. However, the elastic protrusion may be provided on the electrode portion on the secondary terminal side. An elastic protrusion may be provided on the electrode portion.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an ignition coil according to a first embodiment of the present invention.
FIG. 2 is a view showing a high voltage terminal of an ignition coil according to a first embodiment of the present invention.
FIG. 3 is a diagram showing a state where an ignition coil and a spark plug are connected according to a first embodiment of the present invention.
FIG. 4 is a view showing a secondary terminal of the ignition coil according to the first embodiment of the present invention.
FIG. 5 is a view showing a secondary terminal of the ignition coil according to the first embodiment of the present invention.
FIG. 6 is a cross-sectional view showing an ignition coil according to a second embodiment of the present invention.
FIG. 7 is a view showing a resistance member of an ignition coil according to a second embodiment of the present invention.
FIG. 8 is a sectional view showing an ignition coil according to a third embodiment of the present invention.
[Explanation of symbols]
10 ignition coil 11 case 12 tower 13 central core (core)
15 Primary coil 16 Secondary bobbin 17 Secondary coil 21 Connector 22 Terminal 23 High voltage terminal 233 Recess 25 Resistance member 251 Resistance portion 252, 253 Electrode portion 26 Secondary terminal (terminal member)
261 Tubular part 262 Terminal part 263 Leaf spring part (elastic protrusion)
27 Secondary terminal (second terminal member)
271 Cylindrical part 272 Leaf spring part (elastic protrusion)

Claims

A rod-shaped core, a primary bobbin disposed on the outer periphery of the core, a primary coil wound around the primary bobbin, a secondary bobbin disposed on the outer periphery of the primary coil, and the secondary bobbin A secondary coil to be wound, and an ignition coil accommodated in a plug hole of an internal combustion engine,
A terminal part integrally formed from a terminal part and a cylindrical part to which one end of the winding of the secondary coil is connected;
A resistance member having one end accommodated in the tubular portion of the terminal member;
A high-voltage terminal having a connection portion connected to the spark plug and a recess for accommodating the other end of the resistance member;
A plurality of elastic means that are provided on the outer periphery of the resistance member on the high-voltage terminal side and apply a radial biasing force that holds the resistance member;
The cylindrical portion is composed of a bent portion and a flat portion, the bent portion and the flat portion are alternately arranged in the circumferential direction, the cross section is a polygonal shape, and is press-fitted into the secondary bobbin,
Ignition coil, characterized in that provided on the tubular portion, a plurality of elastic projections applying a biasing force in the radial direction for holding the resistive member to the inside of the flat portion is provided.

2. The ignition coil according to claim 1, wherein the cylindrical portion is formed by bending a metal flat plate to have a substantially triangular cross section.

3. The ignition coil according to claim 1, wherein the tubular portion is formed by cutting a flat portion into a U shape and cutting and raising the flat portion to form an elastically deformable leaf spring portion. 4.

2. A second terminal member having a tubular portion and a plurality of elastic protrusions formed on an inner periphery of the tubular portion between the resistance member and the concave portion of the high-voltage terminal. The ignition coil as described in any one of -3.

5. The ignition coil according to claim 4 , wherein the resistance member is formed by covering a substantially cylindrical resistance portion having a ceramic base material with both ends of a substantially bowl-shaped electrode portion.

The ignition coil according to any one of claims 1 to 3, wherein the resistance member is formed by covering a substantially cylindrical resistance portion having a ceramic base material with both ends of a substantially bowl-shaped electrode portion. .

The ignition coil according to claim 6, further comprising a plurality of elastic protrusions on an outer periphery of at least one end of the electrode portion.