JP7249258B2 - electromagnetic fuel injection valve - Google Patents

Description

本発明は、主として内燃機関の燃料供給系に使用される電磁式燃料噴射弁に関し、特に、一端に弁座及び弁孔を有する弁ケーシングと、その弁ケーシングの他端側に設けた固定コアと、その固定コアの周囲を取り囲むコイルと、そのコイルの周囲に配置され、コイルへの通電時、固定コア及び弁ケーシング間に磁気回路を形成するコイルハウジングと、弁座と協働して弁孔を開閉する弁体、並びに磁気回路の形成時に固定コアに吸引されて弁体を開弁する可動コアを有する弁部材と、モールド成形されてコイルハウジングの少なくとも一部を覆うと共にコイルハウジング及びコイル間をシールする樹脂被覆部とを備えた電磁式燃料噴射弁の改良に関する。 TECHNICAL FIELD The present invention relates to an electromagnetic fuel injection valve mainly used in a fuel supply system of an internal combustion engine, and more particularly to a valve casing having a valve seat and a valve hole at one end and a fixed core provided at the other end of the valve casing. , a coil surrounding the fixed core, a coil housing arranged around the coil and forming a magnetic circuit between the fixed core and the valve casing when the coil is energized, and a valve hole cooperating with the valve seat. and a valve member having a movable core that is attracted to the fixed core to open the valve body when a magnetic circuit is formed; and a valve member molded to cover at least a portion of the coil housing and between the coil housing and the coil It relates to an improvement of an electromagnetic fuel injection valve provided with a resin coating portion that seals the .

この種の電磁式燃料噴射弁において、コイルハウジングを、これの成形性を高めるべく、 略半円筒状に各々形成されてコイルを挟むように対向配置される一対のコイルハウジング半体より分割構成したものが知られている（下記特許文献１を参照）。 In this type of electromagnetic fuel injection valve, the coil housing is divided into a pair of coil housing halves which are each formed in a substantially semi-cylindrical shape and arranged opposite to each other so as to sandwich the coil, in order to improve the formability of the coil housing. is known (see Patent Document 1 below).

そして、このものでは、一対のコイルハウジング半体の、周方向で隣り合う側縁の相互間に間隙がそれぞれ設けられており、樹脂被覆部をモールド成形する際に上記間隙を通して樹脂をコイルハウジングとコイル間に充填させ、コイルを絶縁シールするようにしている。 In this case, gaps are provided between the side edges of the pair of coil housing halves that are adjacent in the circumferential direction, and the resin is introduced into the coil housing through the gaps when the resin coating portion is molded. The space between the coils is filled to insulate and seal the coils.

特開２０１４－２１８９２６号公報JP 2014-218926 A

従来の燃料噴射弁では、コイルハウジングとコイル間への樹脂の充填性を十分確保するために、両コイルハウジング半体の、周方向で隣り合う側縁の相互間にかなり広い間隙を設けているが、この広い間隙のためにコイルハウジング周辺での磁束密度（従って弁部材に対する磁気吸引力）が少なからず低下してしまい、弁の作動精度向上を図る上で不利となる。そして、この問題を、例えば各コイルハウジング半体の断面積調整等で対策しようとしても十分にカバーすることは難しい。 In the conventional fuel injection valve, a fairly wide gap is provided between the circumferentially adjacent side edges of both coil housing halves in order to ensure sufficient resin filling between the coil housing and the coil. However, due to this wide gap, the magnetic flux density around the coil housing (and thus the magnetic attraction force to the valve member) is not a little reduced, which is disadvantageous in terms of improving the accuracy of valve operation. It is difficult to solve this problem sufficiently by, for example, adjusting the cross-sectional areas of the coil housing halves.

一方、磁束密度の確保のために上記間隙を狭めた場合には、樹脂の充填性が低下して、コイルハウジングとコイル間のシール性の悪化が懸念される。 On the other hand, if the gap is narrowed in order to ensure the magnetic flux density, there is a concern that the filling performance of the resin will deteriorate, and the sealing performance between the coil housing and the coil will deteriorate.

本発明は、このような事情に鑑みてなされたもので、上記した磁束密度の確保と樹脂の充填性の確保といった相反する課題を一挙に解決可能とした電磁式燃料噴射弁を提供することを目的とする。 SUMMARY OF THE INVENTION It is an object of the present invention to provide an electromagnetic fuel injection valve capable of solving the conflicting problems of securing the magnetic flux density and securing the filling property of the resin at once. aim.

上記目的を達成するために、本発明は、一端に弁座及び弁孔を有する弁ケーシングと、その弁ケーシングの他端側に設けた固定コアと、前記固定コアの周囲を取り囲むコイルと、前記コイルの周囲に配置され、該コイルへの通電時、前記固定コア及び前記弁ケーシング間に磁気回路を形成するコイルハウジングと、前記弁座と協働して前記弁孔を開閉する弁体、並びに前記磁気回路の形成時に前記固定コアに吸引されて前記弁体を開弁する可動コアを有する弁部材と、モールド成形されて前記コイルハウジングの少なくとも一部を覆うと共に該コイルハウジング及び前記コイル間をシールする樹脂被覆部とを備え、前記コイルハウジングが、略半円筒状に各々形成されて前記コイルを挟むように対向配置される一対のコイルハウジング半体より構成されていて、その一対のコイルハウジング半体の、周方向で隣り合う側縁の相互間に間隙がそれぞれ設けられる電磁式燃料噴射弁において、前記樹脂被覆部の、前記コイルハウジングを囲繞する外周側面の周方向の一部には、二本のリブが突設され、前記各リブは、前記コイルハウジング半体の周方向で隣り合う前記側縁に沿うと共に、前記間隙のそれぞれと周方向の位置を一致させたことを第１の特徴とする。
In order to achieve the above object, the present invention provides a valve casing having a valve seat and a valve hole at one end, a fixed core provided at the other end of the valve casing, a coil surrounding the fixed core, and the a coil housing arranged around a coil and forming a magnetic circuit between the fixed core and the valve casing when the coil is energized; a valve body that opens and closes the valve hole in cooperation with the valve seat; a valve member having a movable core that is attracted to the fixed core to open the valve body when the magnetic circuit is formed; and a sealing resin coating portion, and the coil housing is composed of a pair of coil housing halves each formed in a substantially semi-cylindrical shape and arranged oppositely so as to sandwich the coil, and the pair of coil housings In the electromagnetic fuel injection valve in which gaps are provided between the side edges of the halves that are adjacent in the circumferential direction , a part of the outer peripheral side surface of the resin coating portion in the circumferential direction surrounding the coil housing includes: A first feature is that two ribs are provided protruding, and each of the ribs extends along the side edges adjacent to each other in the circumferential direction of the coil housing half and coincides with each of the gaps in the circumferential direction. Characterized by

また本発明は、第１の特徴に加えて、前記一対のコイルハウジング半体は、前記コイルの外周面の少なくとも一部を覆う胴部と、前記胴部の軸方向両端に一対の接続壁部を介してそれぞれ一体に連なり且つ前記固定コア及び前記弁ケーシングにそれぞれ当接、固定される、前記胴部よりも曲率半径が小さい一対の連結部とを各々有しており、前記間隙は、前記一対のコイルハウジング半体における前記胴部の、周方向で隣り合う側縁の相互間に形成される胴部相互間隙部と、前記連結部の、周方向で隣り合う側縁の相互間に形成される連結部相互間隙部とを含み、前記連結部相互間隙部の開き角は、同じ側の前記胴部相互間隙部の最大の開き角よりも小さく設定されることを第２の特徴とする。 In addition to the first feature, the present invention is characterized in that the pair of coil housing halves includes a body portion covering at least a part of the outer peripheral surface of the coil, and a pair of connection wall portions on both ends of the body portion in the axial direction. and a pair of connecting portions having a radius of curvature smaller than that of the body portion, which are integrally connected via and are abutted and fixed to the fixed core and the valve casing, respectively, and the gap is formed by the A gap formed between circumferentially adjacent side edges of the trunks of the pair of coil housing halves, and a trunk gap formed between circumferentially adjacent side edges of the connecting portion. A second feature is that the opening angle of the connecting part gap is set smaller than the maximum opening angle of the body part gap on the same side. .

本発明において、「間隙部の開き角」とは、間隙部の、コイルの中心軸線を基準（即ち中心）とした開き角、換言すれば中心角である。より具体的に言えば、間隙部を相互間に形成する、周方向で隣り合う胴部又は連結部の各一対の側縁と、コイルの中心軸線とを結ぶ２つの直線のなす角度をいう。 In the present invention, the "opening angle of the gap" is the opening angle of the gap with respect to the central axis of the coil (that is, the center), in other words, the central angle. More specifically, it refers to the angle formed by two straight lines connecting each pair of side edges of circumferentially adjacent body portions or connecting portions forming a gap between them and the central axis of the coil.

本発明の第１の特徴によれば、コイルハウジングが、略半円筒状に各々形成されてコイルを挟むように対向配置される一対のコイルハウジング半体より構成され、その両コイルハウジング半体の、周方向で隣り合う側縁の相互間に間隙がそれぞれ設けられる電磁式燃料噴射弁において、樹脂被覆部の外周側面の周方向の一部には、二本のリブが突設され、前記各リブは、コイルハウジング半体の周方向で隣り合う前記側縁に沿うと共に、前記間隙のそれぞれと周方向の位置を一致させているので、磁束密度を確保するために上記間隙を狭くしても、樹脂被覆部のモールド成形時にキャビティのリブ成形部及びその周辺で樹脂が流動し易くなって、リブと対応する上記間隙へも樹脂が流れ込み易くなる。これにより、その間隙を通して各コイルハウジング半体とコイル間へも樹脂を十分に充填させて、その間のシール性を高めることができるため、上記した磁束密度の確保と、樹脂の充填性（従ってコイルのシール性）の確保といった相反する課題を一挙に解決可能となる。しかも、樹脂被覆部の外周部の一部にリブを突設したことで、外周部全体を肉厚とする場合よりも燃料噴射弁を小型軽量化できると共にコスト節減を達成できる。
According to the first feature of the present invention, the coil housing is composed of a pair of coil housing halves each formed in a substantially semi-cylindrical shape and arranged oppositely so as to sandwich the coil. In an electromagnetic fuel injection valve in which gaps are provided between side edges that are adjacent in the circumferential direction, two ribs are protruded from a portion of the outer peripheral side surface of the resin coating portion in the circumferential direction. Each rib extends along the circumferentially adjacent side edges of the coil housing halves and coincides with each of the gaps in the circumferential direction. Also, when molding the resin-coated portion, the resin easily flows in and around the rib-molded portion of the cavity, and the resin easily flows into the gap corresponding to the rib. As a result, resin can be sufficiently filled between the coil housing halves and the coils through the gaps, and the sealability between the gaps can be improved. It is possible to solve conflicting issues such as securing the sealing performance of the product at once. In addition, by protruding ribs from a portion of the outer peripheral portion of the resin coating portion, the fuel injection valve can be made smaller and lighter than when the entire outer peripheral portion is made thick, and cost reduction can be achieved.

また第２の特徴によれば、各々のコイルハウジング半体は、コイルの外周面の少なくとも一部を覆う胴部と、胴部の軸方向両端に一対の接続壁部を介してそれぞれ一体に連なり且つ固定コア及び弁ケーシングにそれぞれ当接、固定される、胴部よりも曲率半径が小さい一対の連結部とを有しており、上記間隙は、第１，第２コイルハウジング半体における胴部の隣り合う側縁の相互間に形成される胴部相互間隙部と、連結部の隣り合う側縁の相互間に形成される連結部相互間隙部とを含み、連結部相互間隙部の開き角は、同じ側の胴部相互間隙部の最大の開き角よりも小さく設定される。これにより、弁ケーシングや固定コアと直接固定されて樹脂による絶縁シールを不要とする上記連結部においては、周方向で隣り合う連結部相互の間隔を十分に狭めて磁束密度の低下を抑えることができるため、弁部に対する吸引力を十分に確保して弁の作動精度向上に寄与することができる。 According to the second characteristic, each of the coil housing halves is integrally connected to a body covering at least a part of the outer peripheral surface of the coil, and a pair of connecting walls at both ends of the body in the axial direction. and a pair of connecting portions having a radius of curvature smaller than that of the body, which are abutted and fixed to the fixed core and the valve casing, respectively. and a gap between connecting parts formed between adjacent side edges of the connecting part, and the opening angle of the gap between connecting parts is set smaller than the maximum opening angle of the gap between the trunks on the same side. As a result, in the connecting portion that is directly fixed to the valve casing or the fixed core and does not require an insulation seal with resin, the gap between the connecting portions adjacent in the circumferential direction can be sufficiently narrowed to suppress the decrease in the magnetic flux density. Therefore, it is possible to secure a sufficient suction force to the valve portion and contribute to improvement in the operation accuracy of the valve.

本発明の第１実施形態に係る電磁式燃料噴射弁の内燃機関への取付状態の一例を示す縦断面図（図４の１－１線断面図）FIG. 4 is a vertical cross-sectional view showing an example of the mounting state of the electromagnetic fuel injection valve according to the first embodiment of the present invention to an internal combustion engine (cross-sectional view along line 1-1 in FIG. 4). 第１実施形態に係る電磁式燃料噴射弁の、図１と同じ側から見た側面図A side view of the electromagnetic fuel injection valve according to the first embodiment, viewed from the same side as in FIG. 図２の３－３線断面図3-3 line sectional view of FIG. （Ａ）は、図１の４Ａ－４Ａ線断面図、また（Ｂ）は、図１の４Ｂ－４Ｂ線断面図(A) is a cross-sectional view along the 4A-4A line in FIG. 1, and (B) is a cross-sectional view along the 4B-4B line in FIG. 第１実施形態に係る電磁式燃料噴射弁のコイルハウジングを単独で示すものであって、（Ａ）は、中間部の平断面図（図４（Ａ）対応断面図）、また（Ｂ）は図５（Ａ）のＢ矢視図、また（Ｃ）は図５（Ａ）のＣ矢視図4(A) is a plane cross-sectional view of an intermediate portion (a cross-sectional view corresponding to FIG. 4(A)), and (B) is a coil housing of the electromagnetic fuel injection valve according to the first embodiment. FIG. 5(A) is a view from arrow B, and (C) is a view from arrow C of FIG. 5(A) 第２実施形態に係る電磁式燃料噴射弁のコイルハウジングを単独で示すものであって、（Ａ）は、中間部の平断面図（図５（Ａ）対応断面図）、また（Ｂ）は、図６（Ａ）のＢ矢視図（図５（Ｂ）対応断面図）、また（Ｃ）は、図６（Ａ）のＣ矢視図（図５（Ｃ）対応断面図）5(A) shows a coil housing alone of an electromagnetic fuel injection valve according to a second embodiment, in which (A) is a plane cross-sectional view of an intermediate portion (a cross-sectional view corresponding to FIG. 5(A)), and (B) is a , and (C) is a view along the arrow B in FIG. 6A (cross-sectional view corresponding to FIG. 5B), and (C) is a view along the arrow C in FIG. 6A (cross-sectional view corresponding to FIG. 5C)

本発明の実施形態を、添付図面に示す本発明の好適な実施例に基づいて以下に説明する。尚、本発明及び本明細書において、「軸方向」「径方向」「周方向」は、電磁式燃料噴射弁Ｉの中心軸線Ｘを基準とするものであって、例えば、中心軸線Ｘに沿う方向が軸方向であり、中心軸線Ｘを中心とした半径方向が径方向であり、中心軸線Ｘを中心とした円周方向が周方向である。また本明細書では、電磁式燃料噴射弁Ｉにおいて、燃料噴射側を前方、燃料入口側を後方という。 Embodiments of the present invention will be described below based on preferred examples of the present invention shown in the accompanying drawings. In the present invention and this specification, "axial direction", "radial direction", and "circumferential direction" are based on the central axis X of the electromagnetic fuel injection valve I. The direction is the axial direction, the radial direction about the central axis X is the radial direction, and the circumferential direction about the central axis X is the circumferential direction. Further, in this specification, in the electromagnetic fuel injection valve I, the fuel injection side is referred to as the front, and the fuel inlet side as the rear.

先ず、第１実施形態を示す図１～図４において、内燃機関用の電磁式燃料噴射弁Ｉの弁ハウジングＩｈは、円筒状の弁座部材３と、この弁座部材３の後端部に嵌合して液密に溶接される磁性円筒体４と、この磁性円筒体４の後端に突き当てて液密に溶接される非磁性円筒体６と、この非磁性円筒体６のの内周面に前端部を嵌合して液密に溶接される円筒状の固定コア５と、この固定コア５の後端に同一素材を以て一体に連設される燃料入口筒２６とを前端から後端に向かって順次連ねて構成される。 First, in FIGS. 1 to 4 showing the first embodiment, a valve housing Ih of an electromagnetic fuel injection valve I for an internal combustion engine includes a cylindrical valve seat member 3 and a rear end portion of the valve seat member 3. A magnetic cylinder 4 fitted and liquid-tightly welded, a non-magnetic cylinder 6 abutted against the rear end of the magnetic cylinder 4 and liquid-tightly welded, and the inner part of the non-magnetic cylinder 6. A cylindrical fixed core 5 whose front end is fitted to the peripheral surface and welded in a liquid-tight manner, and a fuel inlet cylinder 26 integrally connected to the rear end of the fixed core 5 with the same material are arranged from the front end to the rear. They are arranged in series toward the end.

弁座部材３、磁性円筒体４及び非磁性円筒体６は、後述する弁組立体Ｖを収容する弁ケーシング２を構成する。そして、この弁ケーシング２、固定コア５及び燃料入口筒２６よりなる弁ハウジングＩｈは、燃料入口筒２６の後端小径部２６ａを除いて、各部外周面が同一直径に形成される。 The valve seat member 3, the magnetic cylinder 4, and the non-magnetic cylinder 6 constitute a valve casing 2 that accommodates a valve assembly V, which will be described later. The valve housing Ih consisting of the valve casing 2, the fixed core 5 and the fuel inlet tube 26 has the same outer peripheral surface diameter except for the small diameter portion 26a at the rear end of the fuel inlet tube 26. As shown in FIG.

弁座部材３は、その前端面に開口する弁孔７と、この弁孔７の内端に連なる円錐状の弁座８と、この弁座８の大径部に連なる円筒状のガイド孔９とを備えている。弁座部材３の前端面には、上記弁孔７と連通する複数の燃料噴孔１１を有する鋼板製のインジェクタプレート１０が液密に溶接される。 The valve seat member 3 includes a valve hole 7 opening at the front end face, a conical valve seat 8 continuing to the inner end of the valve hole 7, and a cylindrical guide hole 9 continuing to the large diameter portion of the valve seat 8. and A steel plate injector plate 10 having a plurality of fuel injection holes 11 communicating with the valve holes 7 is liquid-tightly welded to the front end face of the valve seat member 3 .

非磁性円筒体６の前端部には、固定コア５と嵌合しない部分が残され、その部分から弁座部材３に至る弁ケーシング２内に、弁部材としての弁組立体Ｖが収納される。 A portion not fitted to the fixed core 5 is left at the front end of the non-magnetic cylindrical body 6, and a valve assembly V as a valve member is housed in the valve casing 2 extending from that portion to the valve seat member 3. .

弁組立体Ｖは、弁座８と協働して弁孔７を開閉するよう前記ガイド孔９を摺動し得る球状の弁体１４と、この弁体１４に溶接により結合される杆部１３を一体に備えた可動コア１２とで構成されるもので、その可動コア１２は、磁性円筒体４の内周面に摺動自在に嵌合、支承されて、固定コア５に対置される。球状の弁体１４の周囲には、燃料の通過を許容する複数の平坦面が形成される。 The valve assembly V comprises a spherical valve body 14 which can slide in the guide hole 9 so as to cooperate with the valve seat 8 to open and close the valve hole 7, and a rod portion 13 joined to the valve body 14 by welding. The movable core 12 is slidably fitted and supported by the inner peripheral surface of the magnetic cylindrical body 4 and opposed to the fixed core 5 . A plurality of flat surfaces are formed around the spherical valve body 14 to allow fuel to pass therethrough.

弁組立体Ｖには、可動コア１２の後端面から始まり杆部１３の中間部で終わる縦孔１９と、この縦孔１９を杆部１３の外周面に開放する横孔２０とが設けられる。縦孔１９の途中には、固定コア５側を向いた環状のばね座２４が形成される。 The valve assembly V is provided with a vertical hole 19 starting from the rear end surface of the movable core 12 and ending at an intermediate portion of the rod portion 13 , and a horizontal hole 20 opening the vertical hole 19 to the outer peripheral surface of the rod portion 13 . An annular spring seat 24 facing the fixed core 5 side is formed in the middle of the vertical hole 19 .

固定コア５は、燃料入口筒２６の中空部を固定コア５の前端面側に連通させる縦孔２１を有する。その縦孔２１は、燃料入口筒２６の中空部より小径になっており、可動コア１２の縦孔１９と連通する。 The fixed core 5 has a vertical hole 21 that communicates the hollow portion of the fuel inlet tube 26 with the front end face side of the fixed core 5 . The vertical hole 21 has a smaller diameter than the hollow portion of the fuel inlet tube 26 and communicates with the vertical hole 19 of the movable core 12 .

この固定コア５の縦孔２１には、すり割り付きパイプ状のリテーナ２３が圧入され、このリテーナ２３と前記ばね座２４との間に可動コア１２を弁体１４の閉弁側に付勢する弁ばね２２が縮設される。その際、リテーナ２３の縦孔２１への嵌合深さにより弁ばね２２のセット荷重が調整される。 A slotted pipe-shaped retainer 23 is press-fitted into the vertical hole 21 of the fixed core 5, and between the retainer 23 and the spring seat 24, the movable core 12 is biased toward the valve closing side of the valve element 14. The valve spring 22 is compressed. At this time, the set load of the valve spring 22 is adjusted by the fitting depth of the retainer 23 into the vertical hole 21 .

可動コア１２には、非磁性材製でリング状のストッパ部材３７が埋設され、このストッパ部材３７は、可動コア１２の、固定コア５と対向する後端面より僅かに突出する。そのストッパ部材３７は、固定及び可動コア５，１２相互の吸引時、ストッパ部材３７が固定コア５の前端面に当接することで、固定コア５及び可動コア１２の対向端面間に所定のギャップを残存させるものである。 A ring-shaped stopper member 37 made of a nonmagnetic material is embedded in the movable core 12 , and the stopper member 37 projects slightly from the rear end surface of the movable core 12 facing the fixed core 5 . The stopper member 37 contacts the front end surface of the fixed core 5 when the fixed and movable cores 5 and 12 are attracted to each other, thereby forming a predetermined gap between the opposed end surfaces of the fixed core 5 and the movable core 12 . It is something that remains.

弁ハウジングＩｈの外周には、固定コア５及び可動コア１２に対応して円筒状のコイル組立体２８が嵌装される。このコイル組立体２８は、磁性円筒体４の後端部から固定コア５にかけてそれらの外周面に嵌合するボビン２９と、これに巻装されるコイル３０とを備える。ボビン２９及びコイル３０は円筒状をなし、これらの中心軸線は、燃料噴射弁Ｉの中心軸線Ｘと一致する。ボビン２９の後端部には、ボビン２９の一側方に突出するカプラ端子３３の基端部３３ａが保持され、このカプラ端子３３にコイル３０の端末が接続される。 A cylindrical coil assembly 28 is fitted around the outer periphery of the valve housing Ih so as to correspond to the fixed core 5 and the movable core 12 . The coil assembly 28 includes a bobbin 29 fitted to the outer peripheral surface of the magnetic cylindrical body 4 from the rear end of the magnetic cylinder 4 to the stationary core 5, and a coil 30 wound thereon. The bobbin 29 and the coil 30 are cylindrical, and their central axes coincide with the central axis X of the fuel injection valve I. As shown in FIG. A base end portion 33 a of a coupler terminal 33 projecting to one side of the bobbin 29 is held at the rear end portion of the bobbin 29 , and the end of the coil 30 is connected to the coupler terminal 33 .

このコイル組立体２８は、それの周囲を磁性体製のコイルハウジングＨで囲繞される。コイルハウジングＨは、これの前後両端部が弁ケーシング２および固定コア５の各外周面に接触、固定される。そして、コイルハウジングＨは、後述するようにコイル３０への通電時に弁ケーシング２及び固定コア５間に磁気回路を形成して、固定コア５に可動コア１２（従って弁組立体Ｖ）を磁気吸引させることができ、これにより、弁体１４が開弁動作する。コイルハウジングＨの具体的構造については、後で詳述する。 This coil assembly 28 is surrounded by a coil housing H made of a magnetic material. Both front and rear ends of the coil housing H contact and are fixed to the outer peripheral surfaces of the valve casing 2 and the fixed core 5 . As will be described later, the coil housing H forms a magnetic circuit between the valve casing 2 and the fixed core 5 when the coil 30 is energized so that the movable core 12 (and thus the valve assembly V) is magnetically attracted to the fixed core 5. This allows the valve element 14 to open. A specific structure of the coil housing H will be described in detail later.

燃料噴射弁Ｉは、これの外郭が、絶縁性の合成樹脂でモールド成形された樹脂被覆部３２により構成される。樹脂被覆部３２は、弁ハウジングＩｈと同心の概略段付き円筒状をなす被覆部本体３２ｍと、その被覆部本体３２ｍの外周部より一側方に突出するカプラ本体部３２ｃとを備える。 The outer shell of the fuel injection valve I is composed of a resin covering portion 32 molded with an insulating synthetic resin. The resin covering portion 32 includes a covering portion main body 32m having a substantially stepped cylindrical shape concentric with the valve housing Ih, and a coupler main body portion 32c projecting to one side from the outer peripheral portion of the covering portion main body 32m.

被覆部本体３２ｍは、これに弁ケーシング２の一部（即ち磁性円筒体４の後半部及び非磁性円筒体６）、固定コア５、及び燃料入口筒２６の大部分（後端部を除く）、並びにコイル組立体２８及びコイルハウジングＨを埋封するようにして、カプラ本体部３２ｃと共にモールド成形される。 The covering main body 32m includes a portion of the valve casing 2 (that is, the rear half of the magnetic cylinder 4 and the non-magnetic cylinder 6), the fixed core 5, and most of the fuel inlet tube 26 (excluding the rear end). , and the coil assembly 28 and the coil housing H are molded together with the coupler body portion 32c.

より具体的に説明すると、被覆部本体３２ｍは、固定コア５の前半部及びコイルハウジングＨを囲繞する中間大径部３２ｍａと、その中間大径部３２ｍａの前側に連設されて磁性円筒体４の後半部を囲繞する前部小径部３２ｍｂと、中間大径部３２ｍａの後側に連設されて固定コア５の後半部及び燃料入口筒２６を囲繞する後部小径部３２ｍｃとを有している。特に中間大径部３２ｍａは、これの前部外周に他の部分よりも小径の縮径部６０を有しており、その縮径部６０と前部小径部３２ｍｂとの間に環状の段差面６１が形成される。 More specifically, the covering portion main body 32m includes an intermediate large-diameter portion 32ma surrounding the front half of the fixed core 5 and the coil housing H, and the magnetic cylindrical body 4 connected to the front side of the intermediate large-diameter portion 32ma. and a rear small-diameter portion 32mc connected to the rear side of the intermediate large-diameter portion 32ma and surrounding the rear half of the stationary core 5 and the fuel inlet tube 26. . In particular, the intermediate large-diameter portion 32ma has a reduced-diameter portion 60 having a smaller diameter than the other portions on its front outer periphery, and an annular step surface is formed between the reduced-diameter portion 60 and the front small-diameter portion 32mb. 61 is formed.

カプラ本体部３２ｃは、これに前記カプラ端子３３を収容、保持するものであって、中間大径部３２ｍａと後部小径部３２ｍｃとに跨がるようにして被覆部本体３２ｍに結合される。そして、カプラ本体部３２ｃとカプラ端子３３とによりカプラ３４が構成される。このカプラ３４には、図示しないが、外部配線に連なる外部カプラが着脱可能に嵌合、接続される。 The coupler main body 32c accommodates and holds the coupler terminal 33, and is connected to the cover main body 32m so as to straddle the middle large-diameter portion 32ma and the rear small-diameter portion 32mc. A coupler 34 is composed of the coupler body portion 32 c and the coupler terminal 33 . The coupler 34 is detachably fitted and connected to an external coupler (not shown) connected to the external wiring.

またカプラ本体部３２ｃは、これの、被覆部本体３２ｍ外周より外側方に張出す根元部分８０の左右側面８１，８２が、燃料噴射弁Ｉの中心軸線Ｘと平行な平坦面に形成される。その左右側面８１，８２間の距離は、後部小径部３２ｍｃの外径と略等しい。 Further, the coupler main body 32c has left and right side surfaces 81, 82 of a root portion 80 projecting outward from the outer periphery of the covering main body 32m and formed into flat surfaces parallel to the central axis X of the fuel injection valve I. The distance between the left and right side surfaces 81, 82 is approximately equal to the outer diameter of the rear small diameter portion 32mc.

また上記根元部分８０は、これの下部の外側方への張出しが上部よりも抑えられていてスリム化が図られているが、その下部の外側面８３には、カプラ３４側に張り出す補強用突出部８３ａが一体に突設される。この補強用突出部８３ａは、カプラ本体部３２ｃの側方張出部分の下面と、中間大径部３２ｍａ（特に後述する第１リブＲｗ）との間を一体に連結してカプラ本体部３２ｃの支持剛性を高めることができる。これにより、カプラ３４が効果的に補強される。 The root portion 80 is slimmed down by having its lower portion 80 less outwardly projecting than its upper portion. A projecting portion 83a is integrally provided. The reinforcing projecting portion 83a integrally connects the lower surface of the side projecting portion of the coupler main body portion 32c and the intermediate large diameter portion 32ma (especially the first rib Rw to be described later) of the coupler main body portion 32c. Support rigidity can be increased. This effectively reinforces the coupler 34 .

一方、燃料噴射弁Ｉを装着すべき内燃機関Ｅ（具体的には機関本体）には、燃料噴射弁Ｉを嵌装、支持するための段付きの弁支持孔７０が設けられる。この弁支持孔７０は、前部小径部３２ｍｂを嵌合させる小径孔部７１と、この小径孔部７１の開口端に環状段部７２を介して連なり且つ中間大径部３２ｍａを嵌合させる大径孔部７３とを有する。 On the other hand, a stepped valve support hole 70 for fitting and supporting the fuel injection valve I is provided in the internal combustion engine E (specifically, the engine body) to which the fuel injection valve I is to be mounted. The valve support hole 70 includes a small-diameter hole portion 71 into which the front small-diameter portion 32mb is fitted, and a large-diameter hole portion 71 that continues to the open end of the small-diameter hole portion 71 via an annular stepped portion 72 and into which the intermediate large-diameter portion 32ma is fitted. and a diameter hole portion 73 .

環状段部７２は、前部小径部３２ｍｂ外周に嵌合されて前部小径部３２ｍｂと大径孔部７３間を液密にシールするシールリング５１の座面となる。即ち、この環状段部７２と、中間大径部３２ｍａ（特に縮径部６０）及び前部小径部３２ｍｂ間の段差面６１との間で、シールリング５１が軸方向に挟持される。 The annular stepped portion 72 serves as a bearing surface of a seal ring 51 that is fitted around the outer periphery of the front small diameter portion 32mb and that seals between the front small diameter portion 32mb and the large diameter hole portion 73 in a liquid-tight manner. That is, the seal ring 51 is axially sandwiched between the annular stepped portion 72 and the step surface 61 between the intermediate large diameter portion 32ma (especially the diameter reduced portion 60) and the front small diameter portion 32mb.

また被覆部本体３２ｍは、前部小径部３２ｍｂの前端に先細りのテーパ面ｆｔを有している。このテーパ面ｆｔは、シールリング５１を前部小径部３２ｍｂに嵌合させる際のガイド面となるため、シールリング５１をスムーズに装着することができる。 Further, the covering portion main body 32m has a tapered surface ft that tapers to the front end of the front small diameter portion 32mb. Since this tapered surface ft serves as a guide surface when fitting the seal ring 51 to the front small diameter portion 32mb, the seal ring 51 can be smoothly mounted.

ところで後部小径部３２ｍｃの外周面には、カプラ本体部３２ｃの根元部分８０よりも後方側において、クッションリング５２を嵌合させるリング取付面６２と、クッションリング５２の座面となる環状突部６３とが設けられる。一方、燃料入口筒２６の後端小径部２６ａの外周面には、樹脂被覆部３２の後部小径部３２ｍｃの後端面が臨む環状シール溝２６ａｇが凹設され、そのシール溝２６ａｇにはシールリング５３が嵌着される。 By the way, on the outer peripheral surface of the rear small diameter portion 32mc, on the rear side of the root portion 80 of the coupler main body portion 32c, there are provided a ring mounting surface 62 for fitting the cushion ring 52, and an annular protrusion 63 serving as a seat surface for the cushion ring 52. is provided. On the other hand, an annular seal groove 26ag facing the rear end surface of the rear small diameter portion 32mc of the resin coating portion 32 is formed in the outer peripheral surface of the rear small diameter portion 26a of the fuel inlet cylinder 26. A seal ring 53 is formed in the seal groove 26ag. is fitted.

また燃料入口筒２６の入口、即ち後端開口には、燃料フィルタ４３の筒状本体４３ｍが固定（例えば圧入）される。そして、その筒状本体４３ｍの外端には、燃料入口筒２６の後端面と係合する取付けフランジ４３ｆが連設される。 A cylindrical main body 43m of the fuel filter 43 is fixed (for example, press-fitted) to the inlet of the fuel inlet tube 26, that is, the rear end opening. A mounting flange 43f that engages with the rear end surface of the fuel inlet tube 26 is continuously provided at the outer end of the tubular body 43m.

而して、不図示の燃料ポンプに連なる燃料分配管５５を、これと環状突部６３との間にクッションリング５２を挟圧すると共に、 シールリング５３を介して燃料入口筒２６に嵌装させる。この状態で、燃料分配管５５を内燃機関Ｅ（例えば機関本体）の適所に固定、例えばボルト止めすることにより、燃料分配管５５と燃料入口筒２６との間が油密に接続されると共に、燃料分配管５５により燃料噴射弁Ｉの前部が弁支持孔７０に押圧、保持される。かくして、燃料噴射弁Ｉが、図１に例示したような設置態様で内燃機関Ｅにセットされる。 A fuel distribution pipe 55 connected to a fuel pump (not shown) is fitted into the fuel inlet tube 26 via a seal ring 53 while a cushion ring 52 is pressed between the fuel distribution pipe 55 and the annular protrusion 63 . In this state, the fuel distribution pipe 55 is fixed, for example, bolted, to an appropriate position of the internal combustion engine E (eg, the engine body), so that the fuel distribution pipe 55 and the fuel inlet cylinder 26 are connected in an oil-tight manner. The fuel distribution pipe 55 presses and holds the front portion of the fuel injection valve I against the valve support hole 70 . Thus, the fuel injection valve I is set in the internal combustion engine E in the manner of installation illustrated in FIG.

尚、本実施形態では、弁支持孔７０を内燃機関Ｅの機関本体に設けたものを示したが、内燃機関Ｅの付属品（例えば、スロットルボディ、吸気管等）に弁支持孔７０を設けてもよい。尚また、弁支持孔７０に対する燃料噴射弁Ｉの、中心軸線Ｘ回りの取付位置を位置決め、保持するための位置決め手段（図示せず）が、弁支持孔７０が設けられる内燃機関Ｅの機関本体又はその付属品と、燃料噴射弁Ｉとの間に設けられる。 In this embodiment, the valve support hole 70 is provided in the engine body of the internal combustion engine E, but the valve support hole 70 is provided in an accessory of the internal combustion engine E (for example, throttle body, intake pipe, etc.). may Positioning means (not shown) for positioning and holding the mounting position of the fuel injection valve I around the central axis X with respect to the valve support hole 70 is provided by the engine body of the internal combustion engine E in which the valve support hole 70 is provided. Alternatively, it is provided between its accessories and the fuel injection valve I.

次に前記コイルハウジングＨについて、図５も併せて参照して説明する。 Next, the coil housing H will be described with reference to FIG. 5 as well.

コイルハウジングＨは、略半円筒状（換言すれば、横断面劣弧状）に各々形成されてコイル組立体２８を挟むように対向配置される第１，第２コイルハウジング半体Ｈ１，Ｈ２より分割構成される。その第１，第２コイルハウジング半体Ｈ１，Ｈ２の、周方向で隣り合う側縁ｅ１，ｅ２；ｅ１′，ｅ２′は、互いに離間して相対向している。従って、その相対向する側縁ｅ１，ｅ２；ｅ１′，ｅ２′の相互間には、燃料噴射弁Ｉの中心軸線Ｘに沿ってスリット状に延びる第１，第２間隙Ｓｗ，Ｓｓがそれぞれ設けられる。 The coil housing H is divided into first and second coil housing halves H1 and H2 which are each formed in a substantially semi-cylindrical shape (in other words, a minor arc shape in cross section) and which are arranged to face each other so as to sandwich the coil assembly 28 therebetween. Configured. Circumferentially adjacent side edges e1, e2; e1', e2' of the first and second coil housing halves H1, H2 face each other while being spaced apart from each other. Accordingly, first and second gaps Sw and Ss extending in a slit shape along the central axis X of the fuel injection valve I are provided between the mutually opposing side edges e1 and e2; e1' and e2', respectively. be done.

第１，第２間隙Ｓｗ，Ｓｓは、上記中心軸線Ｘを通る一直径線上に配列され、また特に第１間隙Ｓｗの方が第２間隙Ｓｓよりも幅広に形成される。しかも上記一直径線の延長線上で、幅広の第１間隙Ｓｗが臨む側に前記カプラ３４が配設される。これは、樹脂被覆部３２のモールド成形過程で、コイルハウジングＨ内（より具体的には第１，第２コイルハウジング半体Ｈ１，Ｈ２とコイル組立体２８との間の空隙２７）と、カプラ本体部３２ｍに対応した金型のキャビティ内との間でモールド樹脂を、比較的幅広の第１間隙Ｓｗを通してスムーズに流動させるためである。 The first and second gaps Sw and Ss are arranged on one diameter line passing through the central axis X, and particularly the first gap Sw is wider than the second gap Ss. Moreover, the coupler 34 is arranged on the extension line of the one diameter line on the side facing the wide first gap Sw. During the molding process of the resin coating portion 32, the inside of the coil housing H (more specifically, the gap 27 between the first and second coil housing halves H1 and H2 and the coil assembly 28) and the coupler This is for allowing the mold resin to smoothly flow through the relatively wide first gap Sw between the inside of the mold cavity corresponding to the main body portion 32m.

而して、樹脂被覆部３２のモールド成形過程で上記空隙２７に充填された樹脂は、各コイルハウジング半体Ｈ１，Ｈ２とコイル組立体２８（従ってコイル３０）との間を絶縁、シールする。 Thus, the resin filled in the gap 27 during the molding process of the resin coating portion 32 insulates and seals between the coil housing halves H1, H2 and the coil assembly 28 (and thus the coil 30).

また第１及び第２コイルハウジング半体Ｈ１，Ｈ２は、コイル組立体２８の外周部を覆う胴部４４と、胴部４４の軸方向両端から半径内方に屈曲してボビン２９の前後両端面に当接する前接続壁部４５及び後接続壁部４６と、前・後接続壁部４５，４６の内周端から軸方向で互いに反対方向に延びる連結部としての前・後連結筒部４７，４８とを各々有している。 The first and second coil housing halves H1 and H2 are composed of a body portion 44 that covers the outer peripheral portion of the coil assembly 28 and both front and rear end surfaces of the bobbin 29 that are bent radially inward from both ends of the body portion 44 in the axial direction. a front connection wall portion 45 and a rear connection wall portion 46 abutting on the front and rear connection wall portions 45 and 46; 48 each.

前・後連結筒部４７，４８は、胴部４４よりも径方向内方側に絞られる関係で、胴部４４よりもコイル３０の中心軸線Ｘからの曲率半径が小さい。そして、その前・後連結筒部４７，４８は、弁ケーシング２（より具体的には磁性円筒体４）および固定コア５の外周面にそれぞれ密接、固定（本実施形態では溶接）される。 The front and rear connecting tubular portions 47 and 48 are narrowed radially inward from the body portion 44 , and have a smaller radius of curvature from the central axis X of the coil 30 than the body portion 44 . The front and rear connecting tubular portions 47 and 48 are closely fixed (welded in this embodiment) to the outer peripheral surfaces of the valve casing 2 (more specifically, the magnetic cylindrical body 4) and the fixed core 5, respectively.

尚、本実施形態において、前・後連結筒部４７，４８は、これが弁ハウジングＩｈ及び固定コア５にそれぞれ溶接される被溶接部が他の部位よりも薄肉に形成される。 そのように被溶接部を薄肉化することで、溶接のためのエネルギ節減が図られる。 In the present embodiment, the front and rear connecting tubular portions 47 and 48 are formed so that the portions to be welded, which are welded to the valve housing Ih and the fixed core 5 respectively, are thinner than other portions. By reducing the thickness of the welded portion in this way, the energy for welding can be saved.

前記した第１，第２間隙Ｓｗ，Ｓｓは、図５に明示されるように、第１及び第２コイルハウジング半体Ｈ１，Ｈ２における胴部４４の、周方向で隣り合う側縁ｅ１ａ，ｅ２ａ；ｅ１ａ′，ｅ２ａ′の相互間に形成される胴部相互間隙部Ｓｗａ，Ｓｓａと、前・後連結筒部４７，４８の、周方向で隣り合う側縁ｅ１ｂ，ｅ２ｂ；ｅ１ｂ′，ｅ２ｂ′の相互間に形成される連結部相互間隙部Ｓｗｂ，Ｓｓｂとを各々含んでいる。 As shown in FIG. 5, the first and second gaps Sw and Ss are defined by the circumferentially adjacent side edges e1a and e2a of the trunk portions 44 of the first and second coil housing halves H1 and H2. body gaps Swa and Ssa formed between e1a' and e2a', and side edges e1b and e2b of the front and rear connecting tubular portions 47 and 48, which are adjacent in the circumferential direction; e1b' and e2b' , each including inter-connection gaps Swb and Ssb formed between the .

しかも、本実施形態において、胴部相互間隙部Ｓｗａ，Ｓｓａの開き角θｗａ，θｓａは、胴部４４の軸方向全域に亘り一定である。従って、その一定の開き角θｗａ，θｓａが、胴部相互間隙部Ｓｗａ，Ｓｓａの最大の開き角θｗａ，θｓａとなる。 Moreover, in the present embodiment, the opening angles θwa and θsa of the gaps Swa and Ssa between the trunk portions are constant throughout the axial direction of the trunk portion 44 . Therefore, the constant opening angles θwa and θsa are the maximum opening angles θwa and θsa of the trunk gaps Swa and Ssa.

一方、連結部相互間隙部Ｓｗｂ，Ｓｓｂの開き角θｗｂ，θｓｂは、前・後連結筒部４７，４８の軸方向全域に亘り一定であり、且つ同じ側の胴部相互間隙部Ｓｗａ，Ｓｓａの開き角θｗａ，θｓａよりも小さく設定（即ち、θｗａ＞θｗｂ，θｓａ＞θｓｂ）されている。 On the other hand, the opening angles θwb and θsb of the joint gaps Swb and Ssb are constant throughout the axial direction of the front and rear joint cylinders 47 and 48, and the gaps Swa and Ssa on the same side are constant. They are set smaller than the opening angles θwa and θsa (that is, θwa>θwb, θsa>θsb).

ここで、胴部相互間隙部Ｓｗａ，Ｓｓａの開き角θｗａ，θｓａは、胴部相互間隙部Ｓｗａ，Ｓｓａの、コイル３０の中心軸線Ｘを基準（即ち中心軸線Ｘより放射状に見た）開き角、換言すれば中心軸線Ｘを中心とした中心角に相当する。より具体的に言えば、胴部相互間隙部Ｓｗａ，Ｓｓａを相互間に形成する、胴部４４の周方向で隣り合う側縁ｅ１ａ，ｅ２ａ；ｅ１ａ′，ｅ２ａ′と、中心軸線Ｘとを結ぶ２つの直線のなす角度をいう。 Here, the opening angles θwa and θsa of the trunk gaps Swa and Ssa are the opening angles of the trunk gaps Swa and Ssa with respect to the central axis X of the coil 30 (that is, viewed radially from the central axis X). , in other words, it corresponds to the central angle about the central axis X. More specifically, the circumferentially adjacent side edges e1a, e2a; The angle between two straight lines.

また、連結部相互間隙部Ｓｗｂ，Ｓｓｂの開き角θｗｂ，θｓｂは、連結部相互間隙部Ｓｗｂ，Ｓｓｂの、コイル３０の中心軸線Ｘを基準（即ち中心軸線Ｘより放射状に見た）開き角、換言すれば中心軸線Ｘを中心とした中心角に相当する。より具体的に言えば、連結部相互間隙部Ｓｗｂ，Ｓｓｂを相互間に形成する、前・後連結筒部４７，４８の周方向で隣り合う側縁ｅ１ｂ，ｅ２ｂ；ｅ１ｂ′，ｅ２ｂ′と、中心軸線Ｘとを結ぶ２つの直線のなす角度をいう。 Further, the opening angles θwb and θsb of the inter-connection gaps Swb and Ssb are the opening angles of the inter-connection gaps Swb and Ssb with respect to the central axis X of the coil 30 (that is, when viewed radially from the central axis X). In other words, it corresponds to the central angle around the central axis X. More specifically, adjacent side edges e1b, e2b; It refers to the angle formed by two straight lines connecting the central axis X.

而して、胴部相互間隙部Ｓｗａ，Ｓｓａの開き角θｗａ，θｓａと、同じ側の連結部相互間隙部Ｓｗｂ，Ｓｓｂの開き角θｗｂ，θｓｂとには、前述のように角度差が存在するが、その角度差は、図５（Ａ）で明らかなように前・後接続壁部４５，４６の、周方向で隣り合う側縁ｅ１ｃ，ｅ２ｃ；ｅ１ｃ′，ｅ２ｃ′において吸収される。即ち、その前・後接続壁部４５，４６の、周方向で隣り合う側縁ｅ１ｃ，ｅ２ｃ；ｅ１ｃ′，ｅ２ｃ′は、相互間の間隙部の開き角度が徐々に変化するような側縁形状に形成される。 As described above, there is an angular difference between the opening angles θwa and θsa of the body gaps Swa and Ssa and the opening angles θwb and θsb of the connecting gaps Swb and Ssb on the same side. However, the angle difference is absorbed by the side edges e1c, e2c; That is, the side edges e1c, e2c; e1c', e2c' adjacent in the circumferential direction of the front and rear connection walls 45, 46 are shaped such that the opening angle of the gap between them gradually changes. formed in

また、第１，第２コイルハウジング半体Ｈ１，Ｈ２は、磁性板をプレス成形して製作されるが、各々の横断面が劣弧状をなすことで、プレス時、深絞りすることなく容易に成形することができる。 The first and second coil housing halves H1 and H2 are manufactured by press-molding a magnetic plate. Since each of the cross-sections has a subarc-shaped cross section, they can be easily formed without deep drawing during pressing. Can be molded.

更に樹脂被覆部３２の、コイルハウジングＨを囲繞する部分（より具体的には被覆部本体３２ｍの中間大径部３２ｍａ）の外周面には、第１，第２間隙Ｓｗ，Ｓｓにそれぞれ対応して第１，第２リブＲｗ，Ｒｓが、樹脂被覆部３２のモールド成形により一体に成形される。 Further, the outer peripheral surface of the portion of the resin coating portion 32 surrounding the coil housing H (more specifically, the middle large diameter portion 32ma of the coating portion main body 32m) corresponds to the first and second gaps Sw and Ss, respectively. The first and second ribs Rw and Rs are integrally molded by molding the resin coating portion 32 .

そして、図５からも明らかなように、第１，第２間隙Ｓｗ，Ｓｓと、これに対応する第１，第２リブＲｗ，Ｒｓとは、各々の少なくとも一部（実施形態では大部分）の周方向位置が互いに一致するように配置される。この配置は、第１，第２間隙Ｓｗ，Ｓｓの径方向外方側から中心軸線Ｘの方向に向かって第１，第２コイルハウジングＨ１，Ｈ２を見た図に相当する図５の（Ｂ）（Ｃ）において、第１，第２間隙Ｓｗ，Ｓｓと、これに対応する第１，第２リブＲｗ，Ｒｓとが各々、広範囲に亘りオーバラップしている点からも明らかである。 As is clear from FIG. 5, the first and second gaps Sw and Ss and the corresponding first and second ribs Rw and Rs are at least part (mostly in the embodiment) of each. are arranged so that their circumferential positions coincide with each other. This arrangement corresponds to a view of the first and second coil housings H1 and H2 viewed from the radially outer side of the first and second gaps Sw and Ss in the direction of the center axis X (B of FIG. 5). ) In (C), the first and second gaps Sw and Ss and the corresponding first and second ribs Rw and Rs respectively overlap over a wide range.

次に前記第１実施形態の作用を説明する。 Next, the operation of the first embodiment will be described.

電磁式燃料噴射弁Ｉの組み立てに当たっては、例えば、コイル組立体２８と、弁ハウジングＩｈの、弁座部材３を除く主要部を各々、別々に製作する。次いで、弁ハウジングＩｈの外周部の所定中間部位にコイル組立体２８を嵌装すると共に、コイル組立体２８を左右から挟んで包み込むように第１及び第２コイルハウジング半体Ｈ１，Ｈ２を左右から相互に近接させる。そして両コイルハウジング半体Ｈ１，Ｈ２の胴部４４内にコイル組立体２８を収めた状態で前連結筒部４７を磁性円筒体４の外周面に、後連結筒部４８を固定コア５の外周面にそれぞれ密着させ、前・後連結筒部４７，４８の薄肉部を複数箇所でレーザ溶接する。こうして、コイルハウジングＨは弁ハウジングＩｈに取付けられる。 In assembling the electromagnetic fuel injection valve I, for example, the main parts of the coil assembly 28 and the valve housing Ih, excluding the valve seat member 3, are manufactured separately. Next, the coil assembly 28 is fitted in a predetermined intermediate portion of the outer periphery of the valve housing Ih, and the first and second coil housing halves H1 and H2 are inserted from the left and right so as to enclose the coil assembly 28 from the left and right. close to each other. Then, with the coil assembly 28 housed in the body portion 44 of both coil housing halves H1 and H2, the front connecting tubular portion 47 is positioned on the outer peripheral surface of the magnetic cylinder 4, and the rear connecting tubular portion 48 is positioned on the outer peripheral surface of the fixed core 5. The thin portions of the front and rear connecting cylindrical portions 47 and 48 are laser-welded at a plurality of locations. Thus, the coil housing H is attached to the valve housing Ih.

しかる後に樹脂被覆部３２のモールド成形工程に移り、絶縁性を有する合成樹脂の射出成形により、コイル組立体２８、コイル組立体２８及びコイルハウジングＨ、並びにカプラ端子３３の基部を埋封するようにして、弁ハウジングＩｈの周囲に樹脂被覆部３２を成形する。その際、第１及び第２コイルハウジング半体Ｈ１，Ｈ２間には、カプラ端子３３の基端部３３ａを挟む側と、その反対側とに第１，第２間隙Ｓｗ，Ｓｓが設けられるから、その両方の間隙Ｓｗ，Ｓｓを通して射出樹脂が各コイルハウジング半体Ｈ１，Ｈ２及びコイル組立体２８間の空隙２７に容易に進入、充填される。これにより、コイル組立体２８を確実に埋封固定すると共に、その絶縁性及び防水性を確保することができる。 After that, the resin coating portion 32 is molded, and the coil assembly 28, the coil assembly 28, the coil housing H, and the base portion of the coupler terminal 33 are embedded by injection molding of an insulating synthetic resin. Then, the resin coating portion 32 is formed around the valve housing Ih. At this time, the first and second gaps Sw and Ss are provided between the first and second coil housing halves H1 and H2 on the side sandwiching the base end portion 33a of the coupler terminal 33 and on the opposite side. , and gaps Sw and Ss, the injection resin easily enters and fills the gap 27 between the coil housing halves H1 and H2 and the coil assembly . As a result, the coil assembly 28 can be reliably embedded and fixed, and its insulation and waterproof properties can be ensured.

樹脂被覆部３２の成形後は、磁性円筒体４内に弁組立体Ｖを収容して、弁座部材３を磁性円筒体４の前端部に嵌合、溶接する。そして燃料入口筒２６側から弁ハウジングＩｈ内に弁ばね２２及びリテーナ２３を装着し、その後、燃料フィルタ４３、シールリング５１，５３及びクッションリング５２を取り付けて、電磁式燃料噴射弁Ｉの組み立て作業は、完了する。 After molding the resin coating portion 32, the valve assembly V is housed in the magnetic cylinder 4, and the valve seat member 3 is fitted to the front end portion of the magnetic cylinder 4 and welded. Then, the valve spring 22 and the retainer 23 are mounted in the valve housing Ih from the side of the fuel inlet cylinder 26, and then the fuel filter 43, the seal rings 51, 53 and the cushion ring 52 are mounted to assemble the electromagnetic fuel injection valve I. is complete.

このようにして組立てられた燃料噴射弁Ｉは、例えば図１に示すような設置態様で内燃機関Ｅの機関本体又はその付属品にセットされる。このセット状態で、燃料ポンプから燃料分配管５５を経て燃料入口筒２６に圧送される燃料は、燃料フィルタ４３で濾過された後、固定コア５及び弁ケーシング２の内部を満たす。そしてコイル３０を消磁した状態では、弁ばね２２の付勢力で弁組立体Ｖは前方に押圧され、弁体１４を弁座８に着座させて弁孔７を閉じる。コイル３０を通電により励磁すると、それにより生ずる磁束がコイルハウジングＨ、磁性円筒体４、可動コア１２、固定コア５を順次走り、両コア５，１２間に発生する磁気吸引力により可動コア１２が弁ばね２２のセット荷重に抗して固定コア５に吸引され、弁体１４が弁座８から離座するので、弁孔７が開放される。これにより、弁座部材３内の高圧燃料が弁孔７を出て、インジェクタプレート１０の燃料噴孔１１から、霧状に噴射される。 The fuel injection valve I assembled in this manner is set in the engine main body of the internal combustion engine E or its accessories in an installation manner as shown in FIG. 1, for example. In this set state, the fuel pressure-fed from the fuel pump to the fuel inlet tube 26 through the fuel distribution pipe 55 is filtered by the fuel filter 43 and then fills the insides of the fixed core 5 and the valve casing 2 . When the coil 30 is demagnetized, the valve assembly V is pushed forward by the biasing force of the valve spring 22, causing the valve body 14 to be seated on the valve seat 8 and the valve hole 7 to be closed. When the coil 30 is excited by energization, the magnetic flux generated thereby runs through the coil housing H, the magnetic cylinder 4, the movable core 12, and the fixed core 5 in sequence, and the magnetic attraction generated between the cores 5 and 12 causes the movable core 12 to move. Since the fixed core 5 is attracted against the set load of the valve spring 22 and the valve element 14 is separated from the valve seat 8, the valve hole 7 is opened. As a result, the high-pressure fuel in the valve seat member 3 exits the valve hole 7 and is injected from the fuel injection hole 11 of the injector plate 10 in the form of mist.

本実施形態の燃料噴射弁Ｉにおいては、コイルハウジングＨが、略半円筒状に各々形成されてコイル組立体２８を挟むように対向配置される第１及び第２コイルハウジング半体Ｈ１，Ｈ２より分割構成され、その両コイルハウジング半体Ｈ１，Ｈ２の、周方向で隣り合う側縁ｅ１，ｅ２；ｅ１′，ｅ２′の相互間に第１，第２間隙Ｓｗ，Ｓｓがそれぞれ設けられ、樹脂被覆部３２の、コイルハウジングＨを囲繞する外周部（より具体的には被覆部本体３２ｍの中間大径部３２ｍａ）には、第１，第２間隙Ｓｗ，Ｓｓに対応して第１，第２リブＲｗ，Ｒｓが突設される。そして、第１，第２間隙Ｓｗ，Ｓｓと、これに対応する第１，第２リブＲｗ，Ｒｓとは、各々の少なくとも一部（実施形態では大部分）の周方向位置が互いに一致するように配置される。 In the fuel injection valve I of this embodiment, the coil housing H is formed from first and second coil housing halves H1 and H2 which are formed in a substantially semi-cylindrical shape and are arranged opposite to each other with the coil assembly 28 interposed therebetween. First and second gaps Sw and Ss are respectively provided between side edges e1 and e2; First and second gaps corresponding to the first and second gaps Sw and Ss are provided on the outer peripheral portion of the covering portion 32 surrounding the coil housing H (more specifically, the intermediate large diameter portion 32ma of the covering portion main body 32m). 2 ribs Rw and Rs are projected. The first and second gaps Sw and Ss and the corresponding first and second ribs Rw and Rs are arranged such that at least a portion (most in the embodiment) of each of them in the circumferential direction coincides with each other. placed in

これにより、コイルハウジングＨ周辺の磁束密度を確保するために第１，第２間隙Ｓｗ，Ｓｓを比較的狭く（即ち従来構造よりも狭く）設定した場合でも、樹脂被覆部３２のモールド成形時にキャビティのリブ成形部及びその周辺で樹脂が流動し易くなって、第１，第２リブＲｗ，Ｒｓと対応する第１，第２間隙Ｓｗ，Ｓｓへも樹脂が流れ込み易くなる。その結果、第１，第２間隙Ｓｗ，Ｓｓを通して各コイルハウジング半体Ｈ１，Ｈ２とコイル組立体２８間の空隙２７へも樹脂を十分に充填させて、その間を確実にシールできるため、磁束密度の確保と、樹脂の充填性（従ってコイル３０のシール性）の確保といった相反する課題を一挙に解決可能となる。しかも、樹脂被覆部３２の中間大径部３２ｍａの一部に第１，第２リブＲｗ，Ｒｓを突設したことで、中間大径部３２ｍａの全体を肉厚とする場合よりも燃料噴射弁Ｉを小型軽量化できると共にコスト節減を達成できる。 As a result, even when the first and second gaps Sw and Ss are set relatively narrow (that is, narrower than the conventional structure) in order to secure the magnetic flux density around the coil housing H, the cavity gap is reduced when the resin coating portion 32 is molded. The resin becomes easy to flow in and around the rib molding portion of , and the resin also becomes easy to flow into the first and second gaps Sw and Ss corresponding to the first and second ribs Rw and Rs. As a result, the gap 27 between the coil housing halves H1, H2 and the coil assembly 28 can be sufficiently filled with the resin through the first and second gaps Sw, Ss, and the gap between them can be reliably sealed. It is possible to solve conflicting problems such as ensuring of .theta. Moreover, since the first and second ribs Rw and Rs are protruding from a part of the intermediate large diameter portion 32ma of the resin coating portion 32, the fuel injection valve is more efficient than the case where the intermediate large diameter portion 32ma is thickened as a whole. I can be made smaller and lighter, and cost savings can be achieved.

その上、本実施形態における各コイルハウジング半体Ｈ１，Ｈ２は、コイル組立体２８の外周面を覆う胴部４４と、胴部４４の軸方向両端に一対の接続壁部４５，４６を介してそれぞれ一体に連なり且つ固定コア５及び弁ケーシング２に直接、溶接される、胴部４４よりも曲率半径が小さい一対の前・後連結筒部４７，４８とを有している。また上記間隙Ｓｗ，Ｓｓは、第１，第２コイルハウジング半体Ｈ１，Ｈ２における胴部４４の、周方向で隣り合う側縁ｅ１ａ，ｅ２ａ；ｅ１ａ′，ｅ２ａ′の相互間に形成される胴部相互間隙部Ｓｗａ，Ｓｓａと、前・後連結筒部４７，４８の、周方向で隣り合う側縁ｅ１ｂ，ｅ２ｂ；ｅ１ｂ′，ｅ２ｂ′の相互間に形成される連結部相互間隙部Ｓｗｂ，Ｓｓｂとを各々含んでおり、しかも各々の連結部相互間隙部Ｓｗｂ，Ｓｓｂの開き角θｗｂ，θｓｂは、これと同じ側の胴部相互間隙部Ｓｗａ，Ｓｓａの開き角θｗａ，θｓａよりも小さく設定（即ち、θｗａ＞θｗｂ，θｓａ＞θｓｂ）されている。 In addition, each of the coil housing halves H1 and H2 in this embodiment includes a trunk portion 44 that covers the outer peripheral surface of the coil assembly 28, and a pair of connection wall portions 45 and 46 at both ends of the trunk portion 44 in the axial direction. It has a pair of front and rear connecting cylinders 47 and 48 which are integrally connected and directly welded to the fixed core 5 and the valve casing 2 and have a radius of curvature smaller than that of the body 44 . The gaps Sw and Ss are formed between the circumferentially adjacent side edges e1a and e2a; gaps Swa, Ssa and side edges e1b, e2b; Ssb, respectively, and the opening angles θwb, θsb of the gaps Swb, Ssb between the connecting portions are set smaller than the opening angles θwa, θsa of the gaps Swa, Ssa between the body portions on the same side. (that is, θwa>θwb, θsa>θsb).

これにより、弁ケーシング２や固定コア５と直接固定されて樹脂による絶縁シールを不要とする前・後連結筒部４７，４８においては、周方向で隣り合う側縁ｅ１ｂ，ｅ２ｂ；ｅ１ｂ′，ｅ２ｂ′相互の間隔を十分に詰めることができて、間隔があくことに因る磁束密度の低下が効果的に抑えられる。従って、弁組立体Ｖに対する磁気吸引力を十分に確保して燃料噴射弁Ｉの作動精度を向上させることができる。 As a result, in the front and rear connecting tubular portions 47 and 48, which are directly fixed to the valve casing 2 and the fixed core 5 and do not require insulating seals by resin, side edges e1b, e2b; 'The space between them can be sufficiently reduced, and the decrease in the magnetic flux density caused by the space can be effectively suppressed. Therefore, a sufficient magnetic attraction force for the valve assembly V can be secured, and the operating accuracy of the fuel injection valve I can be improved.

次に、第２実施形態を、図６を参照して説明する。前記した第１実施形態では、胴部相互間隙部Ｓｗａ，Ｓｓａの開き角θｗａ，θｓａが、胴部４４の軸方向全域に亘り一定であるもの、換言すれば、胴部４４の、周方向で隣り合う側縁ｅ１ａ，ｅ２ａ；ｅ１ａ′，ｅ２ａ′の各端面（即ち切り口）が同一平面であるものを示した。 Next, a second embodiment will be described with reference to FIG. In the above-described first embodiment, the opening angles θwa and θsa of the gaps Swa and Ssa between the trunk portions are constant throughout the axial direction of the trunk portion 44, in other words, in the circumferential direction of the trunk portion 44 Adjacent side edges e1a, e2a; e1a', e2a' are shown to have coplanar end surfaces (that is, cut edges).

これに対し、第２実施形態では、胴部相互間隙部Ｓｗａ，Ｓｓａの開き角θｗａ，θｓａが、胴部４４の軸方向両端部よりも中間部の方が広角に設定され、具体的には、胴部４４の、周方向で隣り合う側縁ｅ１ａ，ｅ２ａ；ｅ１ａ′，ｅ２ａ′の軸方向中間部に、周方向に（より具体的には各胴部４４の周方向中央側に）窪む浅い切欠き状凹部９１，９２；９１′，９２′が形成される。 On the other hand, in the second embodiment, the opening angles θwa and θsa of the gaps Swa and Ssa between the trunk portions are set wider at the intermediate portion than at both ends in the axial direction of the trunk portion 44. Specifically, , circumferentially adjacent side edges e1a, e2a; 91', 92' are formed.

而して、胴部相互間隙部Ｓｗａ，Ｓｓａは、切欠き状凹部９１，９２；９１′，９２′に対応した軸方向中間部の開き角θｗａ，θｓａが、軸方向両端部の開き角θｗａ，θｓａよりも広角となる。従って、その切欠き状凹部９１，９２；９１′，９２′に対応した軸方向中間部の開き角θｗａ，θｓａが、胴部相互間隙部Ｓｗａ，Ｓｓａの最大の開き角θｗａ，θｓａとなる。 91' and 92', the opening angles .theta.wa and .theta.sa at the intermediate portions in the axial direction correspond to the opening angles .theta.wa at both ends in the axial direction. , θsa. Therefore, the opening angles .theta.wa, .theta.sa of the intermediate portions in the axial direction corresponding to the notch-shaped concave portions 91, 92;

そして、図６で明らかなように、この第２実施形態でも、連結部相互間隙部Ｓｗｂ，Ｓｓｂの開き角θｗｂ，θｓｂは、同じ側の胴部相互間隙部Ｓｗａ，Ｓｓａの最大の開き角θｗａ，θｓａよりも小さく設定（即ち、θｗａ＞θｗｂ，θｓａ＞θｓｂ）される。これにより、樹脂による絶縁シールを不要とする前・後連結筒部４７，４８においては、周方向で隣り合う側縁ｅ１ｂ，ｅ２ｂ；ｅ１ｂ′，ｅ２ｂ′相互の間隔を十分に詰めることができるから、磁束密度の低下が効果的に抑えられ、従って、弁組立体Ｖに対する磁気吸引力を十分に確保して燃料噴射弁Ｉの作動精度向上が図られる。 As is clear from FIG. 6, in the second embodiment as well, the opening angles θwb and θsb of the gaps Swb and Ssb between the connecting portions are equal to the maximum opening angle θwa of the gaps Swa and Ssa between the body portions on the same side. , θsa (that is, θwa>θwb, θsa>θsb). As a result, in the front and rear connecting tubular portions 47, 48 which do not require insulating seals by resin, the distance between the side edges e1b, e2b; e1b', e2b' adjacent in the circumferential direction can be sufficiently narrowed. , the decrease in the magnetic flux density is effectively suppressed, so that a sufficient magnetic attraction force to the valve assembly V is ensured, and the operating accuracy of the fuel injection valve I is improved.

第２実施形態のその他の構成は、第１実施形態と同様である。従って、第２実施形態の各構成要素に、第１実施形態の対応する各構成要素と同じ参照符号を付すにとどめ、第２実施形態について更なる構造説明は省略する。 Other configurations of the second embodiment are similar to those of the first embodiment. Accordingly, each component of the second embodiment is given the same reference numerals as the corresponding component of the first embodiment, and further structural description of the second embodiment is omitted.

而して、第２実施形態もまた、第１実施形態と基本的に同様の作用効果を達成することができる。 Therefore, the second embodiment can also achieve basically the same effects as the first embodiment.

以上、本発明の実施形態について説明したが、本発明はそれに限定されることなく、その要旨を逸脱しない範囲で種々の設計変更が可能である。 Although the embodiments of the present invention have been described above, the present invention is not limited thereto, and various design changes are possible without departing from the scope of the invention.

例えば、前記実施形態では、樹脂被覆部３２の、コイルハウジングＨを囲繞する部分の外周面に第１，第２間隙Ｓｗ，Ｓｓにそれぞれ対応して設けられる第１，第２リブＲｗ，Ｒｓの周方向幅を略同幅としたものを例示したが、第１，第２リブＲｗ，Ｒｓは必ずしも同幅に形成する必要はない。例えば、比較的幅広の第１間隙Ｓ１に対応して第１リブＲ１を第２リブＲ２よりも幅広に形成してもよく、この場合には、モールド成形過程で第１間隙Ｓ１を流動する樹脂の流動性が更に向上する。 For example, in the above-described embodiment, the first and second ribs Rw and Rs provided corresponding to the first and second gaps Sw and Ss, respectively, on the outer peripheral surface of the portion of the resin coating portion 32 surrounding the coil housing H. Although the circumferential width is exemplified to be approximately the same width, the first and second ribs Rw and Rs do not necessarily have to be formed to have the same width. For example, the first rib R1 may be formed wider than the second rib R2 to correspond to the relatively wide first gap S1. fluidity is further improved.

また、前記実施形態では、本発明の第２の特徴に合わせて、連結部相互間隙部Ｓｗｂ，Ｓｓｂの開き角θｗｂ，θｓｂを、同じ側の胴部相互間隙部Ｓｗａ，Ｓｓａの最大の開き角θｗａ，θｓａよりも小さく設定（即ち、θｗａ＞θｗｂ，θｓａ＞θｓｂ）したものを例示したが、本発明の第１の特徴を実施するにおいては、連結部相互間隙部Ｓｗｂ，Ｓｓｂの開き角θｗｂ，θｓｂを、同じ側の胴部相互間隙部Ｓｗａ，Ｓｓａの最大の開き角θｗａ，θｓａと略同一（例えば、θｗａ＝θｗｂ，θｓａ＝θｓｂ）に設定した不図示の別実施形態も実施可能である。 Further, in the above-described embodiment, the opening angles θwb and θsb of the gaps Swb and Ssb between the connecting portions are set to the maximum opening angles of the gaps Swa and Ssa on the same side in accordance with the second feature of the present invention. Although the setting smaller than θwa and θsa (that is, θwa>θwb, θsa>θsb) has been exemplified, in carrying out the first feature of the present invention, the opening angle θwb , θsb are substantially the same as the maximum opening angles θwa, θsa of the gaps Swa, Ssa on the same side (for example, θwa=θwb, θsa=θsb). be.

また前記実施形態では、第１，第２コイルハウジング半体Ｈ１，Ｈ２の、周方向で隣り合う側縁ｅ１，ｅ２；ｅ１′，ｅ２′の端面（即ち切り口）を、コイル中心軸線Ｘより概ね放射状に延びる平面に略沿う形状としたものを示したが、周方向で隣り合う上記側縁ｅ１，ｅ２；ｅ１′，ｅ２′の端面形状は、前記実施形態に限定されず、例えば平行な２面に形成してもよい。 Further, in the above-described embodiment, the end surfaces (i.e. cut ends) of side edges e1, e2; Although a shape substantially along a plane extending radially has been shown, the shape of the end faces of the side edges e1, e2; It may be formed on the surface.

Ｉ・・・・・・電磁式燃料噴射弁
Ｈ・・・・・・コイルハウジング
Ｈ１，Ｈ２・・一対のコイルハウジング半体としての第１，第２コイルハウジング半体
ｅ１，ｅ２；ｅ１′，ｅ２′・・コイルハウジング半体の、周方向で隣り合う側縁
ｅ１ａ，ｅ２ａ；ｅ１ａ′，ｅ２ａ′・・胴部の、周方向で隣り合う側縁
ｅ１ｂ，ｅ２ｂ；ｅ１ｂ′，ｅ２ｂ′・・連結筒部の、周方向で隣り合う側縁
Ｒｗ，Ｒｓ・・リブとしての第１，第２リブ
Ｓｗ，Ｓｓ・・間隙としての第１，第２間隙
Ｓｗａ，Ｓｓａ・・胴部相互間隙部
Ｓｗｂ，Ｓｓｂ・・連結部相互間隙部
Ｖ・・・・・・弁部材としての弁組立体
Ｘ・・・・・・燃料噴射弁（コイル）の中心軸線
θｗａ，θｓａ・・胴部相互間隙部の最大の開き角
θｗｂ，θｓｂ・・連結部相互間隙部の開き角
２・・・・・・弁ケーシング
５・・・・・・固定コア
７・・・・・・弁孔
８・・・・・・弁座
１２・・・・・可動コア
１４・・・・・弁体
３０・・・・・コイル
３２・・・・・樹脂被覆部
３２ｍａ・・・樹脂被覆部の、コイルハウジングを囲繞する部分としての中間大径部
４４・・・・・胴部
４５，４６・・一対の接続壁部としての前・後接続壁部
４７，４８・・一対の連結部としての前・後連結筒部 I... Electromagnetic fuel injection valve H... Coil housings H1, H2... First and second coil housing halves e1, e2 as a pair of coil housing halves; e1', e2' side edges e1a, e2a of coil housing halves adjacent in the circumferential direction; e1a', e2a' side edges e1b, e2b adjacent in the body portion; Circumferentially adjacent side edges Rw and Rs of the connecting cylinder portion... First and second ribs Sw and Ss as ribs... First and second gaps as gaps Swa and Ssa... Body portion mutual gaps Swb, Ssb... Gap between connecting parts V... Valve assembly X... Central axes of fuel injection valve (coil) ?wa, ?sa... Gap between body parts opening angle θwb, θsb of . Valve seat 12 Movable core 14 Valve element 30 Coil 32 Resin coated portion 32ma The resin coated portion surrounds the coil housing Intermediate large-diameter portion 44 as a part... Body parts 45, 46... Front and rear connection wall parts 47, 48 as a pair of connection wall parts... Front and rear connection cylinder parts as a pair of connection parts

Claims (2)

一端に弁座（８）及び弁孔（７）を有する弁ケーシング（２）と、その弁ケーシング（２）の他端側に設けた固定コア（５）と、前記固定コア（５）の周囲を取り囲むコイル（３０）と、前記コイル（３０）の周囲に配置され、該コイル（３０）への通電時、前記固定コア（５）及び前記弁ケーシング（２）間に磁気回路を形成するコイルハウジング（Ｈ）と、前記弁座（８）と協働して前記弁孔（７）を開閉する弁体（１４）、並びに前記磁気回路の形成時に前記固定コア（５）に吸引されて前記弁体（１４）を開弁する可動コア（１２）を有する弁部材（Ｖ）と、モールド成形されて前記コイルハウジング（Ｈ）の少なくとも一部を覆うと共に該コイルハウジング（Ｈ）及び前記コイル（３０）間をシールする樹脂被覆部（３２）とを備え、
前記コイルハウジング（Ｈ）が、略半円筒状に各々形成されて前記コイル（３０）を挟むように対向配置される一対のコイルハウジング半体（Ｈ１，Ｈ２）より構成されていて、その一対のコイルハウジング半体（Ｈ１，Ｈ２）の、周方向で隣り合う側縁（ｅ１，ｅ２，ｅ１′，ｅ２′）の相互間に間隙（Ｓｗ，Ｓｓ）がそれぞれ設けられる電磁式燃料噴射弁において、
前記樹脂被覆部（３２）の外周側面の周方向の一部には、二本のリブ（Ｒｗ，Ｒｓ）が突設され、前記各リブ（Ｒｗ，Ｒｓ）は、前記コイルハウジング半体（Ｈ１，Ｈ２）の周方向で隣り合う前記側縁（ｅ１，ｅ２；ｅ１′，ｅ２′）に沿うと共に、前記間隙（Ｓｗ，Ｓｓ）のそれぞれと周方向の位置を一致させたことを特徴とする、電磁式燃料噴射弁。 A valve casing (2) having a valve seat (8) and a valve hole (7) at one end, a fixed core (5) provided at the other end of the valve casing (2), and the periphery of the fixed core (5) and a coil (30) disposed around said coil (30) and forming a magnetic circuit between said fixed core (5) and said valve casing (2) when said coil (30) is energized. A housing (H), a valve body (14) that cooperates with the valve seat (8) to open and close the valve hole (7), and the magnetic circuit that is attracted to the fixed core (5) when the magnetic circuit is formed. A valve member (V) having a movable core (12) for opening a valve body (14); 30) a resin coating portion (32) for sealing between,
The coil housing (H) is composed of a pair of coil housing halves (H1, H2) which are each formed in a substantially semi-cylindrical shape and arranged to face each other so as to sandwich the coil (30). An electromagnetic fuel injection valve in which gaps (Sw, Ss) are respectively provided between circumferentially adjacent side edges (e1, e2, e1', e2') of coil housing halves (H1, H2),
Two ribs (Rw, Rs) protrude from a portion of the outer peripheral side surface of the resin coating portion (32) in the circumferential direction. , H2) along the circumferentially adjacent side edges (e1, e2; e1′, e2′) and aligned with each of the gaps (Sw, Ss) in the circumferential direction. , electromagnetic fuel injection valve. 前記一対のコイルハウジング半体（Ｈ１，Ｈ２）は、前記コイル（３０）の外周部を覆う胴部（４４）と、前記胴部（４４）の軸方向両端に一対の接続壁部（４５，４６）を介してそれぞれ一体に連なり且つ前記固定コア（５）及び前記弁ケーシング（２）にそれぞれ当接、固定される、前記胴部（４４）よりも曲率半径が小さい一対の連結部（４７，４８）とを各々有しており、
前記間隙（Ｓｗ，Ｓｓ）は、前記一対のコイルハウジング半体（Ｈ１，Ｈ２）における前記胴部（４４）の、周方向で隣り合う側縁（ｅ１ａ，ｅ２ａ，ｅ１ａ′，ｅ２ａ′）の相互間に形成される胴部相互間隙部（Ｓｗａ，Ｓｓａ）と、前記連結部（４７，４８）の、周方向で隣り合う側縁（ｅ１ｂ，ｅ２ｂ，ｅ１ｂ′，ｅ２ｂ′）の相互間に形成される連結部相互間隙部（Ｓｗｂ，Ｓｓｂ）とを含み、
前記連結部相互間隙部（Ｓｗｂ，Ｓｓｂ）の開き角（θｗｂ，θｓｂ）は、同じ側の前記胴部相互間隙部（Ｓｗａ，Ｓｓａ）の最大の開き角（θｗａ，θｓａ）よりも小さく設定されることを特徴とする、請求項１に記載の電磁式燃料噴射弁。 The pair of coil housing halves (H1, H2) includes a trunk portion (44) covering the outer peripheral portion of the coil (30) and a pair of connection wall portions (45, 46), and abutted against and fixed to the fixed core (5) and the valve casing (2), respectively, a pair of connecting portions (47) having a radius of curvature smaller than that of the body (44). , 48) and
The gaps (Sw, Ss) are formed between circumferentially adjacent side edges (e1a, e2a, e1a', e2a') of the body portions (44) of the pair of coil housing halves (H1, H2). Between the gaps (Swa, Ssa) formed between the body parts and the side edges (e1b, e2b, e1b', e2b') of the connecting parts (47, 48) adjacent in the circumferential direction and a connecting portion mutual gap (Swb, Ssb),
The opening angles (θwb, θsb) of the gaps between the connecting portions (Swb, Ssb) are set smaller than the maximum opening angles (θwa, θsa) of the gaps between the body portions (Swa, Ssa) on the same side. 2. The electromagnetic fuel injection valve according to claim 1, characterized in that:

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