JP5293219B2

JP5293219B2 - Fuel injection valve

Info

Publication number: JP5293219B2
Application number: JP2009013799A
Authority: JP
Inventors: 直哉当田; 里志菅原
Original assignee: Denso Corp
Current assignee: Denso Corp
Priority date: 2009-01-26
Filing date: 2009-01-26
Publication date: 2013-09-18
Anticipated expiration: 2029-01-26
Also published as: JP2010169048A

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inexpensive fuel injection valve by changing processing of an inlet orifice from oblique hole processing to a horizontal hole processing to facilitate management of processing accuracy and reducing processing man-hours. <P>SOLUTION: In structure of an outlet orifice 62 and an inlet orifice 63 controlling control pressure (back pressure) of a pressure control chamber 61 together with an open/close valve mechanism 5, the pressure control chamber 61 is constituted of a recess part with a conical slope face at an axial center of an end face of a substantially disc-like orifice plate 60 having a cutout at a part of a circumferential part thereof. The outlet orifice 62 is disposed at a tip part of the conical slope face and extended in an axial direction to communicate with the pressure control chamber 61, and the inlet orifice 63 of the horizontal hole processing is formed to a slope part of the conical slope face and extended in a radial direction. An opening part on a side opposite to the inlet orifice of the horizontal hole 65 is sealed with self-sealing blind plug 66, and the other end part of the blind plug 66 abuts on an inner wall face of a valve body 20, to form the inlet orifice 63 as a fuel path closed and independent of an external area. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

本発明は、所定の燃料供給源から燃料を受け入れエンジンに噴射供給する燃料噴射弁に関する。 The present invention relates to a fuel injection valve that receives fuel from a predetermined fuel supply source and supplies the fuel to an engine.

〔従来の技術〕
従来から、燃料噴射弁は、例えば、ディーゼルエンジンのような直噴型のエンジンに搭載され、コモンレール等の燃料供給源から高圧の燃料を受け入れ、エンジンの各気筒内に直接燃料を噴射供給するために用いられている。 [Conventional technology]
Conventionally, a fuel injection valve is mounted on a direct injection type engine such as a diesel engine, for receiving high-pressure fuel from a fuel supply source such as a common rail, and injecting and supplying fuel directly into each cylinder of the engine It is used for.

ディーゼルエンジン用燃料噴射装置に用いられる燃料噴射弁の構造は、ニードルを摺動自在に収容するノズルボディと制御ピストンおよび圧力制御室を備える弁ボディとからなり、圧力制御室の背圧を開閉弁機構により制御して、制御ピストンの付勢力を操作してニードルを開閉する構造のものが公知である（例えば、特許文献１参照）。 The structure of a fuel injection valve used in a fuel injection device for a diesel engine includes a nozzle body that slidably accommodates a needle, a valve body including a control piston and a pressure control chamber, and opens and closes a back pressure in the pressure control chamber. A structure that is controlled by a mechanism to open and close a needle by operating a biasing force of a control piston is known (for example, see Patent Document 1).

特許文献１に開示される燃料噴射弁は、ノズルボディの先端に噴孔と、ノズルボディの内部には軸方向に摺動自在に設けられ、噴孔を開閉するニードルと、ニードルを常に閉弁方向に付勢するスプリングが備えられている。また、コモンレール等の燃料供給源からの高圧燃料が高圧燃料通路を経由して供給されるノズル室を設けている。 The fuel injection valve disclosed in Patent Document 1 is provided with a nozzle hole at the tip of a nozzle body, a needle slidable in the axial direction inside the nozzle body, a needle that opens and closes the nozzle hole, and a valve that is always closed. A spring biasing in the direction is provided. In addition, a nozzle chamber is provided in which high-pressure fuel from a fuel supply source such as a common rail is supplied via a high-pressure fuel passage.

そして、弁ボディの内部には、制御ピストンが摺動自在に収容され、制御ピストンの先端は、ニードルの反噴孔側の軸端部と当接している。また、制御ピストンの反ニードル側の軸端部は、圧力制御室に連通して圧力（背圧）を受け、高圧燃料の供給により、制御ピストンは閉弁方向の付勢力を生じている。 A control piston is slidably accommodated inside the valve body, and the tip of the control piston is in contact with the shaft end of the needle on the side opposite to the injection hole. Further, the shaft end portion of the control piston on the side opposite to the needle communicates with the pressure control chamber and receives pressure (back pressure), and the supply of high pressure fuel causes the control piston to generate a biasing force in the valve closing direction.

圧力制御室は、燃料の供給（加圧）により制御ピストンの閉弁方向の付勢力、および燃料の排出（減圧）により制御ピストンの開弁方向の付勢力を制御するもので、制御ピストンの他端側に配設している。そして、この圧力制御室の背圧は、電磁弁の開閉により駆動される開閉弁機構によって制御される。 The pressure control chamber controls the urging force in the valve closing direction of the control piston by supplying (pressurizing) the fuel and the urging force in the valve opening direction of the control piston by discharging (depressurizing) the fuel. It is arranged on the end side. The back pressure in the pressure control chamber is controlled by an on / off valve mechanism that is driven by opening / closing of an electromagnetic valve.

図５は、従来例として、特許文献１に開示される燃料噴射弁の主要部である開閉弁機構の構造を示し、（ａ）は部分軸断面図であり、（ｂ）はＡ−Ａ断面図である。図５に示すように、開閉弁機構１００は、可動子１０１と、可動子１０１を摺動自在に保持する可動子ホルダ１０２と、および可動子１０１と当接するオリフィスプレート１０３を軸方向に組合せすることで構成される。 FIG. 5 shows a structure of an on-off valve mechanism that is a main part of a fuel injection valve disclosed in Patent Document 1 as a conventional example, where (a) is a partial axial sectional view and (b) is an AA sectional view. FIG. As shown in FIG. 5, the on-off valve mechanism 100 combines a mover 101, a mover holder 102 that slidably holds the mover 101, and an orifice plate 103 that contacts the mover 101 in the axial direction. Consists of.

可動子１０１は図示しない電磁弁に吸引される吸着面を有する平板部１０４と、平板部１０４と垂直に伸びるシャフト部１０５を備え、シャフト部１０５の先端部には円柱状、かつ円錐状に形成された弁体室１０６が設けられ、この弁体室１０６に略半球状のボール弁１０７が回動自在に挿着されている。 The mover 101 includes a flat plate portion 104 having a suction surface attracted by an electromagnetic valve (not shown), and a shaft portion 105 extending perpendicularly to the flat plate portion 104, and is formed in a cylindrical shape and a conical shape at the tip portion of the shaft portion 105. The valve body chamber 106 is provided, and a substantially hemispherical ball valve 107 is rotatably inserted into the valve body chamber 106.

また、オリフィスプレート１０３は円周上の一部を切欠いた略円盤状のプレートで、その一端面の軸中心に円錐状、かつ円柱状の圧力制御室１１０と、他端面の軸中心に出口オリフィス１１１が形成され、さらに、圧力制御室１１０と高圧燃料通路１２０との連通を図るとともに通過する燃料の流量を絞るための入口オリフィス１１２が構成されている。 The orifice plate 103 is a substantially disk-shaped plate with a part cut off on the circumference, a conical and columnar pressure control chamber 110 at the axial center of one end surface, and an outlet orifice at the axial center of the other end surface. 111 is further formed, and an inlet orifice 112 is provided for communication between the pressure control chamber 110 and the high-pressure fuel passage 120 and for restricting the flow rate of the fuel passing therethrough.

そして、図５に示すように、オリフィスプレート１０３の出口オリフィス１１１をシール（閉弁）するようにボール弁１０７および可動子１０１が押圧されて組付けられる。可動子１０１による押圧は、図示しない電磁弁のスプリングの付勢力による。そして、通電により電磁弁がＯＮすると、スプリングの付勢力に抗して可動子１０１の平板部１０４が吸引されて上方へリフトし、これにより、ボール弁１０７は開弁して圧力制御室１１０の高圧燃料が出口オリフィス１１１より流出して圧力制御室１１０の背圧が低下（減圧）するようになっている。 Then, as shown in FIG. 5, the ball valve 107 and the mover 101 are pressed and assembled so as to seal (close the valve) the outlet orifice 111 of the orifice plate 103. The pressing by the mover 101 is due to the biasing force of a spring of a solenoid valve (not shown). When the solenoid valve is turned on by energization, the flat plate portion 104 of the mover 101 is attracted and lifted up against the urging force of the spring, whereby the ball valve 107 is opened and the pressure control chamber 110 is opened. The high pressure fuel flows out from the outlet orifice 111 so that the back pressure in the pressure control chamber 110 decreases (depressurizes).

また、出口オリフィス１１１よりオリフィス面積を小さく（絞り比を大きく）した入口オリフィス１１２からは高圧燃料が供給されて、圧力制御室１１０の圧力回復がなされる。このとき、出口オリフィス１１１と入口オリフィス１１２との絞り比を所定の比率に設定することにより、圧力制御室１１０の背圧の回復圧力を制御でき好適な噴射率プロフィールを得ることができる。従って、入口オリフィス１１２は、燃料噴射弁の噴射特性にかかるキーデバイスであり、その設計および製造において精度確保が重要となり、その精度管理のし易さが重要なポイントとなる。 Further, high pressure fuel is supplied from an inlet orifice 112 having a smaller orifice area (larger throttle ratio) than that of the outlet orifice 111, and pressure recovery in the pressure control chamber 110 is performed. At this time, by setting the throttle ratio between the outlet orifice 111 and the inlet orifice 112 to a predetermined ratio, the recovery pressure of the back pressure in the pressure control chamber 110 can be controlled, and a suitable injection rate profile can be obtained. Therefore, the inlet orifice 112 is a key device related to the injection characteristics of the fuel injection valve, and it is important to ensure accuracy in the design and manufacture thereof, and the ease of accuracy management is an important point.

従来では、図５に示すように、オリフィスプレート１０３の軸中心の他端側に出口オリフィス１１１と、一端側に円錐状の圧力制御室１１０が連通して形成される。そして、入口オリフィス１１２は、圧力制御室１１０の円錐斜面に略垂直に設けられた傾斜誘導孔１１３と、他端側に高圧燃料通路１２０と連通する垂直誘導孔１１４と、および垂直誘導孔１１４と連通する傾斜誘導孔１１５とが形成され、傾斜誘導孔１１５と傾斜誘導孔１１３とを略直交させるとともに両者の間に所定の寸法を確保した上で極めて小径の孔を形成して構成される。 Conventionally, as shown in FIG. 5, an outlet orifice 111 is formed on the other end side of the axial center of the orifice plate 103, and a conical pressure control chamber 110 is formed on one end side. The inlet orifice 112 includes an inclined guide hole 113 provided substantially perpendicular to the conical slope of the pressure control chamber 110, a vertical guide hole 114 communicating with the high-pressure fuel passage 120 on the other end side, and a vertical guide hole 114. An inclined guide hole 115 is formed, and the inclined guide hole 115 and the inclined guide hole 113 are substantially orthogonal to each other, and a very small diameter hole is formed while ensuring a predetermined dimension therebetween.

従って、この入口オリフィス１１２は、出口オリフィス１１１と圧力制御室１１０との軸心に対し傾斜した斜め孔加工によるオリフィス構造となる。そして、複雑に傾斜する何段かの独立した誘導孔を繋げて圧力制御室１１０と高圧燃料通路１２０とを連通する１本の外部領域にリークすることのない閉鎖した燃料経路が出口オリフィス１１１と一体的にオリフィスプレート１０３に構成される。これにより、入口オリフィス１１２の所定の絞り特性は幾度の調整によって作り込まれ、精度が確保されるものである。 Therefore, the inlet orifice 112 has an orifice structure formed by oblique hole machining inclined with respect to the axis of the outlet orifice 111 and the pressure control chamber 110. A closed fuel path that does not leak to one external region that connects the pressure control chamber 110 and the high-pressure fuel passage 120 by connecting a plurality of independent guide holes that incline in a complicated manner is connected to the outlet orifice 111. The orifice plate 103 is integrally formed. Thereby, the predetermined throttle characteristic of the inlet orifice 112 is created by several adjustments, and the accuracy is ensured.

〔従来技術の不具合〕
しかし、オリフィスプレート１０３に出口オリフィス１１１と一体的に構成する斜め孔加工の入口オリフィス１１２は、予め傾斜誘導孔１１３と、垂直誘導孔１１４、および傾斜誘導孔１１５を加工した後に極めて小径の孔加工によって実現するものであり、工程数および加工工数が掛かるとともに斜め孔加工であることより精度管理がし難いという問題がある。 [Problems with conventional technology]
However, the inlet orifice 112 for machining the oblique hole integrally formed with the outlet orifice 111 in the orifice plate 103 is formed with an extremely small diameter after machining the inclined guiding hole 113, the vertical guiding hole 114, and the inclined guiding hole 115 in advance. There is a problem that the number of processes and the number of processing steps are increased, and the accuracy control is difficult due to the oblique hole processing.

特開２００６−３０７７４２号公報JP 2006-307742 A

本発明は、上記の問題点を解決するためになされたものであり、その目的は、入口オリフィスの加工を斜め孔加工から横孔加工に変更して、加工精度の管理を容易にするとともに加工工数を低減し、低コストの燃料噴射弁を提供することにある。 The present invention has been made to solve the above-mentioned problems, and its purpose is to change the processing of the inlet orifice from the oblique hole processing to the horizontal hole processing, thereby facilitating management of processing accuracy and processing. The object is to provide a low-cost fuel injection valve with reduced man-hours.

〔請求項１の手段〕
請求項１に記載の燃料噴射弁によれば、ノズルとノズルニードルを備えた噴射弁本体と、噴射弁本体からの燃料噴射を断続する電磁弁とからなり、電磁弁は、電磁ソレノイドと付勢手段と電磁ソレノイドの磁力により駆動される可動子とからなる開閉弁機構を備えており、開閉弁機構は、可動子に設けた弁体が出口オリフィスを開閉することにより、ノズルニードルと連動する制御ピストンに作用する圧力制御室の背圧を制御して、ノズルニードルを開閉して燃料を噴射供給する燃料噴射弁において、圧力制御室は、略円盤状の円周部の一部に切欠きを有するオリフィスプレートの一端面の軸心に円錐状の斜面を有する凹部からなり、円錐状の斜面の先端部には軸方向に向う出口オリフィスが設けられて圧力制御室と連通し、円錐状の斜面の傾斜部には径方向に向う横孔加工の入口オリフィスが設けられ、横孔の反入口オリフィス側の開口部は盲栓によって閉塞され、外部領域と閉鎖して独立した燃料経路を出口オリフィスと一体的にオリフィスプレートに形成したことを特徴としている。 [Means of Claim 1]
According to the fuel injection valve of the first aspect, the fuel injection valve includes an injection valve main body having a nozzle and a nozzle needle, and an electromagnetic valve for intermittently injecting fuel from the injection valve main body. The electromagnetic valve is energized with the electromagnetic solenoid. And an open / close valve mechanism comprising a mover driven by the magnetic force of an electromagnetic solenoid, and the open / close valve mechanism is controlled in conjunction with the nozzle needle by opening and closing the outlet orifice by a valve body provided on the mover. In a fuel injection valve that controls the back pressure of the pressure control chamber acting on the piston and opens and closes the nozzle needle to inject fuel, the pressure control chamber has a notch in a part of a substantially disc-shaped circumferential portion. The orifice plate has a concave portion having a conical slope at the axial center of one end surface thereof, and an outlet orifice directed in the axial direction is provided at the tip of the conical slope to communicate with the pressure control chamber. of The slanted part is provided with an inlet orifice for processing a horizontal hole in the radial direction, the opening on the side opposite to the inlet orifice of the horizontal hole is closed by a blind plug, and it is closed with the external region so that an independent fuel path is integrated with the outlet orifice. It is characterized by being formed into an orifice plate.

これにより、加工が容易な横孔構造の入口オリフィスが高い寸法精度で製造し易くなり、燃料噴射弁の良好な噴射特性が維持できる。また、横孔加工だけで入口オリフィスが製造できるので加工工程並びに工数が大幅に低減でき、コストダウンが可能となる。 As a result, it is easy to manufacture an inlet orifice having a lateral hole structure that is easy to process with high dimensional accuracy, and good injection characteristics of the fuel injection valve can be maintained. Further, since the inlet orifice can be manufactured only by the horizontal hole machining, the machining process and the number of processes can be greatly reduced, and the cost can be reduced.

また、請求項１に記載の燃料噴射弁によれば、盲栓は、有底円筒状のキャップ構造を有し、少なくとも円筒部の表面積が底部の断面積より大きく、円筒部を形成する壁厚が、弾性変形可能な所定の厚みを有し、横孔の開口部に圧入されて、内部に高圧燃料の内圧を受けて内径が拡径することにより、横孔と盲栓との接触面圧を増加してセルフシール（自密閉）することを特徴としている。 According to the fuel injection valve of claim 1 , the blind plug has a bottomed cylindrical cap structure, and at least the surface area of the cylindrical portion is larger than the cross-sectional area of the bottom portion, and the wall thickness forming the cylindrical portion Has a predetermined thickness that can be elastically deformed, and is press-fitted into the opening of the lateral hole, and the internal diameter of the lateral hole and the blind plug is increased by receiving the internal pressure of the high-pressure fuel inside. The self-sealing (self-sealing) is increased.

これにより、高圧の燃料圧力の作用により盲栓の軸方向作用力（つまり、抜け力）よりも盲栓の径方向作用力（つまり、保持力）の方が大きくでき、燃料圧力が高圧になればなるほど抜けにくくなり、高圧の燃料シールが確実となる。 As a result, the radial action force (ie, holding force) of the blind plug can be made larger than the axial action force (ie, pulling force) of the blind plug due to the action of high pressure fuel pressure, and the fuel pressure can be increased. The more difficult it is to remove, the higher the pressure of the fuel seal.

〔請求項２の手段〕
請求項２に記載の燃料噴射弁によれば、盲栓は、有底円筒状のキャップ構造を有し、円筒部を形成する壁厚が、塑性変形可能な一様な所定の厚み、または局部的な凹溝の形成による所定の厚みを有し、横孔の開口部には、その内周面に所定の凹溝が設けられており、盲栓が横孔の開口部に圧入されて、内部に高圧燃料の内圧を受けて内径が拡径することにより、塑性変形の張り出しを形成し、抜け止めを構成したことを特徴としている。
これにより、高圧の燃料圧力の作用により盲栓の軸方向作用力（つまり、抜け力）が増加しても抜けを防止でき、かつ高圧の燃料シールを確実とする。 [Means of claim 2 ]
According to the fuel injection valve of claim 2 , the blind plug has a bottomed cylindrical cap structure, and the wall thickness forming the cylindrical portion is a uniform predetermined thickness that can be plastically deformed, or a local portion. Having a predetermined thickness due to the formation of a typical concave groove, the opening of the horizontal hole is provided with a predetermined concave groove on its inner peripheral surface, and a blind plug is press-fitted into the opening of the horizontal hole, It is characterized in that the internal diameter of the high-pressure fuel is increased to increase the inner diameter, thereby forming an overhang of plastic deformation, thereby constituting a stopper.
Thereby, even if the axial action force (that is, the withdrawal force) of the blind plug increases due to the action of the high-pressure fuel pressure, it can be prevented from coming off, and a high-pressure fuel seal is ensured.

〔請求項３の手段〕
請求項３に記載の燃料噴射弁によれば、盲栓は、横孔の開口部に圧入した盲栓の他端を切欠き部の端面より突出させ、弁ボディの内壁面と当接させたことを特徴としている。
これにより、弁ボディの内壁面がストッパとなり、盲栓が抜けるのを防止できる。 [Means of claim 3 ]
According to the fuel injection valve of the third aspect , the blind plug has the other end of the blind plug press-fitted into the opening of the lateral hole protruded from the end surface of the notch and brought into contact with the inner wall surface of the valve body. It is characterized by that.
Thereby, the inner wall surface of the valve body serves as a stopper, and it is possible to prevent the blind plug from coming off.

〔請求項４の手段〕
請求項４に記載の燃料噴射弁によれば、入口オリフィスは、オリフィスプレートの切欠きのない円周部の所定の位置に形成される径方向に向う横孔の中心側に設けられ、横孔の反入口オリフィス側の円周部には、盲栓が面一となるまで圧入され、弁ボディの内壁面内にオリフィスプレートが収容されることを特徴としている。
これにより、盲栓の他端を切欠き部の横孔位置より突出させることなく、短い盲栓のままで盲栓が抜けるのを防止できる。 [Means of claim 4 ]
According to the fuel injection valve of claim 4 , the inlet orifice is provided at the center side of the radially extending lateral hole formed at a predetermined position of the circumferential portion of the orifice plate not having a notch. This is characterized in that an orifice plate is accommodated in the inner wall surface of the valve body by press-fitting a blind plug into the circumferential portion on the opposite inlet orifice side until the blind plug becomes flush.
Thereby, without letting the other end of the blind plug protrude from the lateral hole position of the notch, it is possible to prevent the blind plug from coming off while keeping the short blind plug.

燃料噴射弁の全体構成断面図である（実施例１）。1 is an overall configuration cross-sectional view of a fuel injection valve (Example 1). 燃料噴射弁の要部を示し、（ａ）は部分軸断面図であり、（ｂ）はＡ−Ａ断面図である（実施例１）。The principal part of a fuel injection valve is shown, (a) is a partial axial sectional view, and (b) is an AA sectional view (Example 1). 燃料噴射弁の要部を示し、（ａ）は部分軸断面図であり、（ｂ）はＡ−Ａ断面図である（実施例１の変形例）。The principal part of a fuel injection valve is shown, (a) is a partial axial sectional view, (b) is an AA sectional view (modified example of Example 1). 燃料噴射弁の要部を示し、（ａ）は部分軸断面図であり、（ｂ）はＡ−Ａ断面図である（実施例２）。The principal part of a fuel injection valve is shown, (a) is a partial axial sectional view, (b) is an AA sectional view (Example 2). 燃料噴射弁の要部を示し、（ａ）は部分軸断面図であり、（ｂ）はＡ−Ａ断面図である（従来例）。The principal part of a fuel injection valve is shown, (a) is a partial axial sectional view, (b) is an AA sectional view (conventional example).

本発明の最良の実施形態を、図に示す実施例１とともに説明する。 The best mode of the present invention will be described together with Example 1 shown in the drawings.

〔実施例１の構成〕
図１から図３は本発明の実施例１を示したもので、図１は燃料噴射弁の全体構成断面図であり、図２は図１に示す燃料噴射弁の要部を示し、（ａ）は部分軸断面図であり、（ｂ）はＡ−Ａ断面図である。また、図３は他の燃料噴射弁の要部を示し、（ａ）は部分軸断面図であり、（ｂ）はＡ−Ａ断面図である。 [Configuration of Example 1]
FIGS. 1 to 3 show a first embodiment of the present invention, FIG. 1 is a sectional view of the overall configuration of the fuel injection valve, FIG. 2 shows a main part of the fuel injection valve shown in FIG. ) Is a partial axial sectional view, and (b) is an AA sectional view. Moreover, FIG. 3 shows the principal part of another fuel injection valve, (a) is a partial axial sectional view, and (b) is an AA sectional view.

燃料噴射弁１は噴射弁本体２と、噴射弁本体２の後端に装着した電磁弁３と、先端側に締結した燃料の噴射ノズル４とからなる。電磁弁３は、図示しないエンジン制御装置（ＥＣＵ）から送出される制御信号により制御される。なお、以下の説明では、燃料噴射弁の噴射ノズル側を一端側または先端側、電磁弁側を他端側または後端側という。 The fuel injection valve 1 includes an injection valve main body 2, an electromagnetic valve 3 attached to the rear end of the injection valve main body 2, and a fuel injection nozzle 4 fastened to the front end side. The solenoid valve 3 is controlled by a control signal sent from an engine control unit (ECU) (not shown). In the following description, the injection nozzle side of the fuel injection valve is referred to as one end side or the front end side, and the electromagnetic valve side is referred to as the other end side or the rear end side.

噴射弁本体２は、軸心に貫通したシリンダ２１が設けられるとともに、シリンダ２１に並行して高圧燃料通路２２、および低圧燃料通路２３が設けられ、高圧燃料通路２２に高圧燃料を供給する筒状のインレット部２６と、低圧燃料通路２３に連通して低圧燃料を外部に排出するアウトレット部２７とを備えた棒状の弁ボディ２０と、弁ボディ２０のシリンダ２１の内部に収容され、後記するニードル４３の閉弁方向に付勢力を伝達する制御ピストン１７と、制御ピストン１７の背圧の大きさを制御する圧力制御室６１等からなる。 The injection valve body 2 is provided with a cylinder 21 penetrating the shaft center, and is provided with a high-pressure fuel passage 22 and a low-pressure fuel passage 23 in parallel with the cylinder 21, and a cylindrical shape for supplying high-pressure fuel to the high-pressure fuel passage 22. A rod-shaped valve body 20 having an inlet portion 26 and an outlet portion 27 that communicates with the low-pressure fuel passage 23 and discharges low-pressure fuel to the outside, and a needle that is housed in a cylinder 21 of the valve body 20 to be described later 43 includes a control piston 17 that transmits the urging force in the valve closing direction 43, a pressure control chamber 61 that controls the magnitude of the back pressure of the control piston 17, and the like.

弁ボディ２０の後端側には、円筒状の電磁弁設置室１０が設けられ、電磁弁設置室１０には電磁弁３が装着されてリテーニングナット２４により締結されている。
電磁弁３は、電磁弁設置室１０の後端側に設置された電磁ソレノイド３０、および電磁弁設置室１０の先端側に設置された開閉弁機構５からなる。 A cylindrical electromagnetic valve installation chamber 10 is provided on the rear end side of the valve body 20, and the electromagnetic valve 3 is mounted in the electromagnetic valve installation chamber 10 and fastened by a retaining nut 24.
The electromagnetic valve 3 includes an electromagnetic solenoid 30 installed on the rear end side of the electromagnetic valve installation chamber 10 and an on-off valve mechanism 5 installed on the front end side of the electromagnetic valve installation chamber 10.

電磁ソレノイド３０は、強磁性材製で後端が鍔状の円筒の外周に、複合磁性材を積層した磁気コアを配し、磁気コアの外周を強磁性材製外筒で包囲し、磁気コア内に電磁コイル３１を配設した構造を有する。電磁ソレノイド３０の先端面は、後述する可動子５０を吸引する吸引面となっており、鍔状の円筒の先端部は、可動子５０が当接するストッパ面となっている。 The electromagnetic solenoid 30 has a magnetic core in which a composite magnetic material is laminated on the outer periphery of a cylinder made of a ferromagnetic material and has a bowl-shaped rear end, and the outer periphery of the magnetic core is surrounded by an outer cylinder made of a ferromagnetic material. The electromagnetic coil 31 is disposed inside. The front end surface of the electromagnetic solenoid 30 is a suction surface that sucks a mover 50 to be described later, and the front end of the bowl-shaped cylinder is a stopper surface with which the mover 50 comes into contact.

開閉弁機構５は、電磁弁設置室１０の先端側の可動子室１５内に配置され、可動子５０と可動子５０を保持する可動子ホルダ５１とを有する。そして、可動子室１５の先端側はやや径小のプレート室１６が構成され、略円盤状のオリフィスプレート６０が収容されている。 The on-off valve mechanism 5 is disposed in a mover chamber 15 on the distal end side of the electromagnetic valve installation chamber 10, and includes a mover 50 and a mover holder 51 that holds the mover 50. A plate chamber 16 having a slightly smaller diameter is formed on the distal end side of the mover chamber 15, and a substantially disc-shaped orifice plate 60 is accommodated therein.

可動子５０は、平板部５２およびシャフト部５３を有し、平板部５２は、図示しない放射状に複数（本実施例では３個）の切欠きを有し、その上面が略平面であり、電磁ソレノイド３０の先端面に吸着される吸着面となっており、可動子室１５内に配設されている。シャフト部５３は円柱状を呈し、可動子ホルダ５１の中心穴に摺動自在に嵌め込まれている。可動子ホルダ５１は、電磁弁設置室１０の内周に螺合され、締結軸力を生じ、オリフィスプレート６０をプレート室１６の端面に接合させている。 The mover 50 has a flat plate portion 52 and a shaft portion 53. The flat plate portion 52 has a plurality of (not shown in the drawing) radial notches (three in this embodiment), and the upper surface thereof is substantially flat. It is an adsorption surface that is adsorbed to the front end surface of the solenoid 30, and is disposed in the mover chamber 15. The shaft portion 53 has a cylindrical shape and is slidably fitted into the center hole of the mover holder 51. The mover holder 51 is screwed into the inner periphery of the electromagnetic valve installation chamber 10 to generate a fastening axial force, and joins the orifice plate 60 to the end surface of the plate chamber 16.

そして、可動子５０は、電磁ソレノイド３０の軸心内に配されたばね３２で先端方向（閉弁方向）に付勢され、電磁コイル３１で生じた磁力により後端方向（開弁方向）に吸引されて先後端方向（図中上下）に移動（リフト）する。 The mover 50 is urged in the distal direction (valve closing direction) by a spring 32 disposed in the axial center of the electromagnetic solenoid 30 and is attracted in the rear end direction (valve opening direction) by the magnetic force generated by the electromagnetic coil 31. Then, it moves (lifts) in the front-rear direction (up and down in the figure).

シャフト部５３の先端面の中心には、円筒部および円錐部からなる弁体室５５が設けられ、弁体室５５には窒化珪素製のボール弁５６が収容されている。ボール弁５６は上面が球状であるが、下面はオリフィスプレート６０の上面の出口オリフィス６２を塞ぐシール平面状となっている。 A valve body chamber 55 composed of a cylindrical portion and a conical portion is provided at the center of the front end surface of the shaft portion 53, and a ball valve 56 made of silicon nitride is accommodated in the valve body chamber 55. The ball valve 56 has a spherical upper surface, but the lower surface has a sealing flat shape that closes the outlet orifice 62 on the upper surface of the orifice plate 60.

オリフィスプレート６０は、その外周端面の一部に切欠きを有する略円盤状であり、その先端面には、その中心に円錐形状の凹部が形成され、圧力制御室６１を形成し、この中心の後端側に出口オリフィス６２が設けられている。 The orifice plate 60 has a substantially disk shape having a notch in a part of the outer peripheral end surface thereof, and a conical recess is formed at the center of the tip surface of the orifice plate 60 to form a pressure control chamber 61. An outlet orifice 62 is provided on the rear end side.

インレット部２６の内部には、高圧燃料流入路１１が設けられ、高圧燃料通路２２、２８に分岐して連通する。高圧燃料通路２８は、オリフィスプレート６０に設けられた入口オリフィス６３と連通し、圧力制御室６１の回復圧力を制御している。また、高圧燃料通路２２はノズルボディ４０に設けられた傾斜する高圧燃料流路４１を経由してノズル室４２と連通し、噴射のための高圧燃料を供給するとともに、供給された高圧燃料がニードル４３の受圧面に作用し、開弁方向に付勢力を発生させている。 A high-pressure fuel inflow passage 11 is provided inside the inlet portion 26 and branches into and communicates with the high-pressure fuel passages 22 and 28. The high-pressure fuel passage 28 communicates with an inlet orifice 63 provided in the orifice plate 60 and controls the recovery pressure in the pressure control chamber 61. The high-pressure fuel passage 22 communicates with the nozzle chamber 42 via an inclined high-pressure fuel passage 41 provided in the nozzle body 40, and supplies high-pressure fuel for injection. Acting on the pressure receiving surface 43, an urging force is generated in the valve opening direction.

また、アウトレット部２７の内部には、低圧燃料流出路１２が設けられ、低圧燃料通路２９と連通し、低圧燃料通路２９は可動子室１５と連通し、さらに、可動子室１５はプレート室１６を経由して低圧燃料通路２３と連通している。従って、アウトレット部２７からは、圧力制御室６１に設けられた出口オリフィス６２から流出路１３を経由して流出する制御用燃料と、低圧燃料通路２３を経由して流れるニードル４３の摺動部からリークして噴射されなかった余剰燃料とをまとめて外部に排出する。 Further, the low pressure fuel outflow passage 12 is provided inside the outlet portion 27, communicates with the low pressure fuel passage 29, the low pressure fuel passage 29 communicates with the mover chamber 15, and the mover chamber 15 further includes the plate chamber 16. And communicates with the low-pressure fuel passage 23. Therefore, from the outlet portion 27, from the sliding portion of the control fuel flowing out from the outlet orifice 62 provided in the pressure control chamber 61 through the outflow passage 13 and the needle 43 flowing through the low pressure fuel passage 23. Excess fuel that has leaked and was not injected is collected and discharged to the outside.

制御ピストン１７は、２段長柱状に形成され、シリンダ２１内を摺動可能とするクリアランスシール型の摺動部１８と、径小の摺動部を有しないプレッシャピン部１９からなり、プレッシャピン部１９の先端は、常に、ニードル４３の後端と当接している。また、制御ピストン１７の後端は円錐台形状等を有して圧力制御室６１に臨み、圧力制御室６１に供給される高圧燃料の圧力を受けてニードル４３の閉弁方向の付勢力を発生させている。 The control piston 17 is formed in a two-stage long columnar shape, and includes a clearance seal type sliding portion 18 that can slide in the cylinder 21 and a pressure pin portion 19 that does not have a small-diameter sliding portion. The tip of the portion 19 is always in contact with the rear end of the needle 43. Further, the rear end of the control piston 17 has a truncated cone shape or the like, faces the pressure control chamber 61, receives the pressure of the high-pressure fuel supplied to the pressure control chamber 61, and generates a biasing force in the valve closing direction of the needle 43. I am letting.

また、弁ボディ２０の先端側に、シリンダ２１の内径より径大のばね室４４が設けられ、ばね４５が２つのばね受座４６との間に介装され、常にニードル４３を先端方向（閉弁方向）に付勢している。 Further, a spring chamber 44 having a diameter larger than the inner diameter of the cylinder 21 is provided on the distal end side of the valve body 20, and a spring 45 is interposed between the two spring seats 46 so that the needle 43 is always in the distal direction (closed). Energized in the valve direction).

噴射ノズル４は大径部のノズルボディ４０および小径部のノズル４７を有する二段筒型形状であり、ノズルボディ４０の中心に、ニードル４３を収容するニードル穴４８が形成されている。ニードル４３は２段長柱状に形成され、径大部は摺動自在となるクリアランスシール型のニードル摺動部３８と、径小部は高圧燃料の通路となるニードル燃料通路部３９を構成する。また、ニードル燃料通路部３９の上流側のニードル穴４８側の中間位置には径大の大容積を有するノズル室４２が、傾斜する高圧燃料流路４１と交差して設けられている。 The injection nozzle 4 has a two-stage cylindrical shape having a large-diameter nozzle body 40 and a small-diameter nozzle 47, and a needle hole 48 for accommodating the needle 43 is formed at the center of the nozzle body 40. The needle 43 is formed in a two-stage long column shape, and a large diameter portion constitutes a clearance seal type needle sliding portion 38 that is slidable, and a small diameter portion constitutes a needle fuel passage portion 39 that serves as a high pressure fuel passage. Further, a nozzle chamber 42 having a large diameter and a large volume is provided at an intermediate position on the needle hole 48 side upstream of the needle fuel passage portion 39 so as to intersect with the inclined high pressure fuel passage 41.

また、ニードル燃料通路部３９の下流側のニードル穴４８の先端には、テーパ構造のノズル先端室が構成され、高圧燃料を噴霧する１個もしくは複数個の適切な数の噴孔４９が設けられている。そして、このノズルボディ４０が弁ボディ２０の先端にリテーニングナット２５によって締結されて、燃料噴射弁１を構成する。 Further, at the tip of the needle hole 48 on the downstream side of the needle fuel passage portion 39, a nozzle tip chamber having a tapered structure is formed, and one or a plurality of appropriate number of injection holes 49 for spraying high pressure fuel are provided. ing. The nozzle body 40 is fastened to the tip of the valve body 20 by a retaining nut 25 to constitute the fuel injection valve 1.

ここで、本実施例では、本発明になる横孔加工による入口オリフィス６３を出口オリフィス６２と一体的にオリフィスプレート６０に形成したことを特徴としている。以下に、この構成を図２に基づいて詳しく説明する。 Here, the present embodiment is characterized in that the inlet orifice 63 by the horizontal hole processing according to the present invention is formed in the orifice plate 60 integrally with the outlet orifice 62. Hereinafter, this configuration will be described in detail with reference to FIG.

図２に示すように、本発明になるオリフィスプレート６０は、略円盤状のプレートであり、円周部の一部がオリフィスプレート６０の軸方向と一致する方向に切欠かれて空間をなし、燃料の流路を形成している。そして、オリフィスプレート６０の一端面の軸中心に円錐状、かつ円柱状の圧力制御室６１と、他端面の軸中心に出口オリフィス６２が形成され、互いに軸心を一致して連通している。 As shown in FIG. 2, the orifice plate 60 according to the present invention is a substantially disk-shaped plate, and a part of the circumference is cut away in a direction coinciding with the axial direction of the orifice plate 60 to form a space. The flow path is formed. A conical and columnar pressure control chamber 61 is formed at the axial center of one end face of the orifice plate 60, and an outlet orifice 62 is formed at the axial center of the other end face.

また、オリフィスプレート６０の切欠き部には、切欠き面に垂直に径方向に向う横孔６５が所定の深さまで形成され、その所定の深さの略中間位置にて垂直誘導孔６４と交差する。そして、その所定の深さの横孔６５の中心側に、さらに、極めて小径の孔が加工されて入口オリフィス６３が形成される。このとき、入口オリフィス６３の圧力制御室６１に対する配置箇所は、本実施例では図２に示すように、円錐状に傾斜する斜面であるが、これに限ることなく、円柱状の側面であってもよい。 Further, a lateral hole 65 extending in the radial direction perpendicular to the notch surface is formed in the notch portion of the orifice plate 60 to a predetermined depth, and intersects with the vertical guide hole 64 at a substantially intermediate position of the predetermined depth. To do. Then, an extremely small diameter hole is further processed on the center side of the lateral hole 65 of the predetermined depth to form the inlet orifice 63. At this time, the arrangement position of the inlet orifice 63 with respect to the pressure control chamber 61 is a slope inclined in a conical shape as shown in FIG. 2 in this embodiment. Also good.

従来例のように、袋穴の内部に、しかも円錐状に傾斜する斜面に対し、垂直でなく傾斜したままで極めて小径の孔加工による入口オリフィス６３を形成することは非常に難しかった故に、複雑に傾斜する何段かの傾斜誘導孔を設けて、互いの誘導孔が直交する配置を実現し、この位置に小径の孔加工を実施して所定の精度を確保する斜め孔加工の入口オリフィス６３を形成せざるを得なかったものが、本実施例で適用する横孔加工では、円錐状に傾斜する斜面に傾斜したままで加工することが容易となる。 As in the conventional example, it is very difficult to form the inlet orifice 63 by drilling a very small diameter hole while maintaining the inclination inside the bag hole and not inclined to the conical inclined surface. Inclined hole processing inlet orifice 63 is provided in which a plurality of inclined guiding holes are provided so as to realize an arrangement in which the guiding holes are orthogonal to each other, and a small-diameter hole is formed at this position to ensure a predetermined accuracy. However, in the case of the horizontal hole machining applied in the present embodiment, it is easy to machine the film while inclining on a slope inclined in a conical shape.

そして、横孔６５の反入口オリフィス側の開口部に盲栓６６を圧入して横孔６５を塞ぎ、外部領域にリークすることのない閉鎖して独立した燃料経路となる入口オリフィス６３を形成する。なお、盲栓６６から僅かなリークが生じても、入口オリフィス６３による圧力制御室６１の背圧の回復圧力が変わることにより、燃料噴射弁１の噴射特性、例えば噴射率プロフィールが変わってしまう恐れがあり、僅かなリークの発生も認められるものではなく、経年的にも信頼性が要求される。 Then, a blind plug 66 is press-fitted into the opening of the side hole 65 on the side opposite to the inlet orifice to close the side hole 65, and an inlet orifice 63 that forms a closed and independent fuel path without leaking to the outside region is formed. . Even if a slight leak occurs from the blind plug 66, the recovery characteristic of the back pressure of the pressure control chamber 61 by the inlet orifice 63 may change, thereby changing the injection characteristics of the fuel injection valve 1, for example, the injection rate profile. The occurrence of slight leaks is not recognized, and reliability over time is required.

盲栓６６は、所定の長さを有した円柱状部材であり、一端側（圧入側）に所定の深さの座ぐり穴が形成されて圧入部が有底円筒状に加工されたキャップ状部材である。そして、有底円筒状の圧入部の壁厚は所定の厚さに加工されて内圧に対して適度な弾性変形を許容するようになっている。 The blind plug 66 is a cylindrical member having a predetermined length, and has a cap shape in which a counterbore having a predetermined depth is formed on one end side (press-fit side) and the press-fit portion is processed into a bottomed cylindrical shape. It is a member. The wall thickness of the bottomed cylindrical press-fit portion is processed to a predetermined thickness to allow an appropriate elastic deformation with respect to the internal pressure.

また、有底円筒状の圧入部の底深さは、その底深さに至る円筒状の表面積がその有底部断面積より大きくなるように設定され、キャップ状の盲栓６６の内部に作用する高圧燃料の内圧によって、盲栓６６の軸方向に作用する抜け力よりも径方向に作用する保持力を大きくし、圧入部の径が弾性的に拡径し圧入部と横孔６５との接触面圧を増加させるもので、内圧の増加に呼応してシール性が促進する所謂セルフシール（自密閉）の構成をなすものである。 Further, the bottom depth of the bottomed cylindrical press-fitting portion is set so that the cylindrical surface area reaching the bottom depth is larger than the cross-sectional area of the bottomed portion, and acts inside the cap-shaped blind plug 66. Due to the internal pressure of the high-pressure fuel, the holding force acting in the radial direction is made larger than the pulling force acting in the axial direction of the blind plug 66, the diameter of the press-fit portion is elastically expanded, and the contact between the press-fit portion and the lateral hole 65 is increased. It increases the surface pressure and forms a so-called self-seal (self-sealing) structure in which sealing performance is promoted in response to an increase in internal pressure.

そして、本実施例では、所定の長さを有した盲栓６６の横孔６５への圧入を、図２に示すように、一端側の圧入部を所定の位置まで圧入し、他端側は切欠き面より突出させて組付け、他端側の端部を弁ボディ２０のプレート室１６の内壁面と当接させて組付けている。これにより、盲栓６６の最悪時の抜け防止を保証する。 In this embodiment, as shown in FIG. 2, the press-fitting part on one end side is press-fitted to a predetermined position, and the other end side is inserted into the horizontal hole 65 of the blind plug 66 having a predetermined length. It is assembled by projecting from the notch surface, and the end of the other end is brought into contact with the inner wall surface of the plate chamber 16 of the valve body 20. This guarantees the worst prevention of the blind plug 66 from coming off.

〔実施例１の作用〕
本実施例の燃料噴射弁１は、電磁ソレノイド３０が通電されオンすると、可動子５０は電磁力により吸引されて後端方向に移動し、そして、可動子５０に連動してボール弁５６が上位に変位し、出口オリフィス６２が開放されて低圧燃料の流出路１３に連通するため、圧力制御室６１内の背圧は低圧となる。すると、制御ピストン１７の付勢力と制御ピストン１７と連動したニードル４３のノズル室４２に作用する付勢力とのバランスが崩れ、ニードル４３は制御ピストン１７と共に後端方向へ移動し、噴孔４９を開放するとともに、ノズル室４２からの高圧燃料が噴孔４９から噴霧する。このとき、出口オリフィス６２のオリフィス径より径小に、かつ、精度よく形成された入口オリフィス６３は高圧燃料を供給させながら圧力制御室６１の圧力回復を開始し、正確な圧力回復パターンによって所定の噴射率プロフィールを実現する。 [Operation of Example 1]
In the fuel injection valve 1 of this embodiment, when the electromagnetic solenoid 30 is energized and turned on, the mover 50 is attracted by the electromagnetic force and moves in the rear end direction. Since the outlet orifice 62 is opened and communicated with the low-pressure fuel outflow passage 13, the back pressure in the pressure control chamber 61 is low. Then, the balance between the urging force of the control piston 17 and the urging force acting on the nozzle chamber 42 of the needle 43 interlocked with the control piston 17 is lost, and the needle 43 moves together with the control piston 17 toward the rear end, and the nozzle hole 49 is moved through the nozzle hole 49. While being opened, high-pressure fuel from the nozzle chamber 42 is sprayed from the nozzle hole 49. At this time, the inlet orifice 63, which is smaller than the orifice diameter of the outlet orifice 62 and accurately formed, starts the pressure recovery of the pressure control chamber 61 while supplying the high-pressure fuel, and a predetermined pressure recovery pattern is used. Realize the injection rate profile.

そして、電磁ソレノイド３０の通電がオフされると、可動子５０がばね３２の付勢力で先端方向に移動し、ボール弁５６が出口オリフィス６２を塞ぎ、入口オリフィス６３から高圧燃料圧が圧力制御室６１に作用し、制御ピストン１７は付勢力によって先端方向に移動し、これとともにニードル４３は噴孔４９を塞いで、燃料の噴射は終了する。 When the energization of the electromagnetic solenoid 30 is turned off, the mover 50 is moved in the distal direction by the urging force of the spring 32, the ball valve 56 closes the outlet orifice 62, and the high pressure fuel pressure is supplied from the inlet orifice 63 to the pressure control chamber. Acting on 61, the control piston 17 is moved in the distal direction by the urging force. At the same time, the needle 43 closes the injection hole 49, and the fuel injection is completed.

〔実施例１の効果〕
本実施例では、開閉弁機構５とともに圧力制御室６１の制御圧（背圧）を制御する出口オリフィス６２と入口オリフィス６３の組合せにおいて、圧力制御室６１は、略円盤状の円周部の一部に切欠きを有するオリフィスプレート６０の一端面の軸心に円錐状の斜面を有する凹部からなり、円錐状の斜面の先端部には軸方向に向う出口オリフィス６２が設けられて圧力制御室６１と連通し、円錐状の斜面の傾斜部には径方向に向う横孔加工の入口オリフィス６３が設けられ、横孔６５の反入口オリフィス側の開口部はセルフシール型の盲栓６６によってシールされ、さらに盲栓６６の他端部を弁ボディ２０の内壁面と当接させて、外部領域と閉鎖して独立した燃料経路となる入口オリフィス６３を形成する。 [Effect of Example 1]
In the present embodiment, in the combination of the outlet orifice 62 and the inlet orifice 63 that controls the control pressure (back pressure) of the pressure control chamber 61 together with the on-off valve mechanism 5, the pressure control chamber 61 has a substantially disc-shaped circumferential portion. A pressure control chamber 61 is provided with an outlet orifice 62 directed in the axial direction at the tip of the conical slope. In the inclined part of the conical slope, an inlet orifice 63 for processing a horizontal hole in the radial direction is provided, and the opening on the side opposite to the inlet orifice of the horizontal hole 65 is sealed by a self-sealing type blind plug 66. Further, the other end portion of the blind plug 66 is brought into contact with the inner wall surface of the valve body 20 to form an inlet orifice 63 that is closed from the outer region and becomes an independent fuel path.

これにより、加工が容易な横孔構造の入口オリフィス６３が高い寸法精度で製造し易くなり、燃料噴射弁１の良好な噴射特性が維持できる。また、横孔加工だけで入口オリフィス６３が製造できるので加工工程並びに工数が大幅に低減でき、コストダウンが可能となる。 As a result, the inlet orifice 63 having a side hole structure that is easy to process can be easily manufactured with high dimensional accuracy, and the good injection characteristics of the fuel injection valve 1 can be maintained. Further, since the inlet orifice 63 can be manufactured only by the horizontal hole processing, the processing steps and the number of processes can be greatly reduced, and the cost can be reduced.

また、盲栓６６は有底円筒状の所定の壁厚を有するキャップ状構造であって、高圧燃料の内圧を受けて接触面圧を増加するセルフシール（自密閉）型であるため、高圧の燃料圧力の作用により盲栓６６の軸方向の抜け力よりも径方向の保持力の方が大きくなって、シールを確実にするとともに抜けの防止が図れる。 The blind plug 66 is a bottomed cylindrical cap-like structure having a predetermined wall thickness and is a self-sealing type that increases the contact surface pressure by receiving the internal pressure of the high-pressure fuel. Due to the action of the fuel pressure, the holding force in the radial direction is larger than the axial pulling force of the blind plug 66, so that the sealing can be ensured and the slipping can be prevented.

また、横孔６５に圧入した盲栓６６の他端部を切欠き部の横孔位置より突出させ、弁ボディ２０の内壁面と当接させたので、内壁面がストッパとなり、盲栓６６が抜けるのを防止できる。 Further, since the other end of the blind plug 66 press-fitted into the horizontal hole 65 is protruded from the position of the horizontal hole of the notch and brought into contact with the inner wall surface of the valve body 20, the inner wall surface serves as a stopper, It can be prevented from coming off.

〔変形例〕
本変形例は、図３に示すように、有底円筒状の盲栓６６の壁厚をさらに一様に薄くする、もしくは壁厚を構成する内周面に断面が円弧状、あるいは三角状の環状の凹溝６７を形成して局部的に壁厚が所定の薄さになるよう加工したものである。そして、この盲栓６６を圧入してシールを確保する横孔６５の開口部の内周面の、盲栓６６の圧入部に形成される凹溝６７と対向する近傍位置に、同様に、断面が円弧状、あるいは三角状の環状の凹溝６８が形成されている。 [Modification]
In this modification, as shown in FIG. 3, the wall thickness of the bottomed cylindrical blind plug 66 is made even thinner, or the inner peripheral surface constituting the wall thickness has a circular arc shape or a triangular shape. An annular groove 67 is formed and locally processed so that the wall thickness becomes a predetermined thickness. Similarly, in the vicinity of the inner peripheral surface of the opening of the lateral hole 65 that press-fits the blind plug 66 and secures the seal, in the vicinity of the concave groove 67 formed in the press-fitted portion of the blind plug 66, the cross section A circular concave groove 68 having a circular arc shape or a triangular shape is formed.

壁厚を薄くするのは、高圧の燃料圧力の内圧により壁部が弾性変形を超えて塑性変形を起し易くするもので、所定の内圧以上でこの凹溝６７の壁部が外周側に凸状に塑性変形を起こして張り出し、この凸状の張り出しが横孔６５の開口部の内周面に設けた環状の凹溝６８と噛み合い、盲栓６６に作用する内圧による抜け力に対抗する抜け止めとなる。 The wall thickness is reduced because the internal pressure of the high fuel pressure causes the wall to exceed the elastic deformation and easily cause plastic deformation, and the wall of the groove 67 protrudes to the outer peripheral side at a predetermined internal pressure or higher. This projecting projecting protrusion meshes with an annular groove 68 provided in the inner peripheral surface of the opening of the lateral hole 65, and is pulled out to resist the pulling force due to the internal pressure acting on the blind plug 66. Stop.

なお、本変形例の盲栓６６に設けた環状の凹溝６７等の薄壁部の張り出し変形は、高圧の燃料圧力による塑性変形によって形成され、仮に、燃料圧力が除圧されて低下しても弾性変形のように復元することなく変形は残留するものである。 It should be noted that the overhanging deformation of the thin wall portion such as the annular groove 67 provided in the blind plug 66 of this modification is formed by plastic deformation due to the high fuel pressure, and the fuel pressure is reduced and reduced. However, the deformation remains without being restored like elastic deformation.

従って、一度所定の圧力以上の高圧の燃料圧力が作用して塑性変形による張り出し変形が生じれば、その後幾度の高圧の燃料圧力が作用しても塑性変形は進行しない。よって、張り出し部は材料破断することはない。これにより、一旦張り出し変形による抜け止めが形成すれば、シールも抜け防止も完全となるため、盲栓６６の円筒部の表面積を底部の断面積より大きくする必要はなく、盲栓６６の圧入部の長さを大幅に短くすることができる。 Therefore, once a high pressure fuel pressure higher than a predetermined pressure is applied to cause an overhanging deformation due to plastic deformation, the plastic deformation does not proceed no matter how many high pressure fuel pressures are applied thereafter. Therefore, the overhanging portion does not break the material. As a result, once the stopper is formed by overhanging deformation, the seal and the prevention of disconnection are complete. Therefore, it is not necessary to make the surface area of the cylindrical portion of the blind plug 66 larger than the cross-sectional area of the bottom plug 66. Can be significantly shortened.

〔実施例２の構成〕
本発明の実施例２を図４に示す。図４は、実施例２における燃料噴射弁の要部を示し、（ａ）は部分軸断面図であり、（ｂ）はＡ−Ａ断面図である。実施例１と実質的に同一構成部分に同一符号を付して、詳細な説明は省略する。 [Configuration of Example 2]
A second embodiment of the present invention is shown in FIG. FIGS. 4A and 4B show a main part of the fuel injection valve according to the second embodiment, where FIG. 4A is a partial axial sectional view and FIG. 4B is an AA sectional view. Components that are substantially the same as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

実施例１の燃料噴射弁１では、開閉弁機構５とともに圧力制御室６１の背圧を制御する出口オリフィス６２および入口オリフィス６３の組合せを略円盤状のオリフィスプレート６０に一体的に構成し、入口オリフィス６３はオリフィスプレート６０の切欠き部の切欠き面に垂直に径方向に向う横孔加工によって形成され、横孔６５の開口部を盲栓６６によってシールする構成である。 In the fuel injection valve 1 according to the first embodiment, the combination of the outlet orifice 62 and the inlet orifice 63 that controls the back pressure of the pressure control chamber 61 together with the on-off valve mechanism 5 is integrally formed in a substantially disc-shaped orifice plate 60. The orifice 63 is formed by processing a horizontal hole that is perpendicular to the cut surface of the cutout portion of the orifice plate 60 in the radial direction, and the opening of the horizontal hole 65 is sealed by a blind plug 66.

本実施例では、実施例１とは異なり、略円盤状のオリフィスプレート６０の切欠きのない円周部の所定の位置に横孔６５と横孔６５が略中間部にて交差する垂直誘導孔６４を加工し、横孔６５の中心側に、さらに、極めて小径の孔が加工されて入口オリフィス６３が形成され、横孔６５の開口部を盲栓６６によってシールすることを特徴とするものである。 In the present embodiment, unlike the first embodiment, a vertical guide hole in which the horizontal hole 65 and the horizontal hole 65 intersect at a substantially intermediate portion at a predetermined position on the circumferential portion without a notch of the substantially disc-shaped orifice plate 60. 64 is machined, and an extremely small diameter hole is further machined in the center side of the lateral hole 65 to form an inlet orifice 63, and the opening of the lateral hole 65 is sealed by a blind plug 66. is there.

図４に示すように、本発明になるオリフィスプレート６０は、略円盤状のプレートであり、円周部の一部がオリフィスプレート６０の軸方向と一致する方向に切欠かれて空間をなし、燃料の流路を形成している。そして、オリフィスプレート６０の一端面の軸中心に円錐状、かつ円柱状の圧力制御室６１と、他端面の軸中心に出口オリフィス６２が形成され、互いに軸心を一致して連通している。この構成は実施例１と異なるところはない。 As shown in FIG. 4, the orifice plate 60 according to the present invention is a substantially disk-shaped plate, and a part of the circumference is cut away in a direction coinciding with the axial direction of the orifice plate 60 to form a space. The flow path is formed. A conical and columnar pressure control chamber 61 is formed at the axial center of one end face of the orifice plate 60, and an outlet orifice 62 is formed at the axial center of the other end face. This configuration is not different from the first embodiment.

異なるのは、オリフィスプレート６０の切欠き部でない円周部の所定の位置に、円周部の端面に垂直に径方向に向う横孔６５が所定の深さまで形成され、その所定の深さの略中間位置に垂直誘導孔６４が形成され、交差するように構成されている。 The difference is that a lateral hole 65 extending in a radial direction perpendicular to the end face of the circumferential portion is formed to a predetermined depth at a predetermined position of the circumferential portion that is not a notch portion of the orifice plate 60, and has a predetermined depth. A vertical guide hole 64 is formed at a substantially intermediate position and is configured to intersect.

そして、その所定の深さの横孔６５の中心側に、さらに、極めて小径の孔が加工されて入口オリフィス６３が形成される。そして、横孔６５の反入口オリフィス側の開口部に盲栓６６を圧入して横孔６５を塞ぎ、外部領域にリークすることのない閉鎖して独立した燃料経路となる入口オリフィス６３を構成する。 Then, an extremely small diameter hole is further processed on the center side of the lateral hole 65 of the predetermined depth to form the inlet orifice 63. Then, a blind plug 66 is press-fitted into the opening on the side opposite to the inlet orifice of the horizontal hole 65 to close the horizontal hole 65, and an inlet orifice 63 that forms a closed and independent fuel path without leaking to the external region is formed. .

盲栓６６は、その形状並びに構造、およびその圧入後の作用は、実施例１と同様であり詳細な説明は省略する。 The shape and structure of the blind plug 66 and the action after the press-fitting are the same as those in the first embodiment, and detailed description thereof is omitted.

ただ、さらに１点異なるところとして、所定の長さを有した盲栓６６の圧入を、図４に示すように、盲栓６６の他端部が円周部より突出せずに略面一となるよう圧入している。そして、盲栓６６が圧入されたオリフィスプレート６０を弁ボディ２０のプレート室１６内に収容し、組付けるのみで、盲栓６６の他端部をプレート室１６の内壁面と当接させている。これにより、盲栓６６が抜けるのを防止する。 However, as a further difference, as shown in FIG. 4, the press-fitting of the blind plug 66 having a predetermined length is substantially flush with the other end of the blind plug 66 not protruding from the circumferential portion. It is press-fitted to become. Then, the orifice plate 60 into which the blind plug 66 is press-fitted is accommodated in the plate chamber 16 of the valve body 20, and the other end portion of the blind plug 66 is brought into contact with the inner wall surface of the plate chamber 16 only by being assembled. . This prevents the blind plug 66 from coming off.

〔実施例２の効果〕
本実施例では、入口オリフィス６３がオリフィスプレート６０の切欠き部でない円周部の所定の位置に垂直に径方向の横孔加工によって形成したので、横孔６６の開口部をシールする盲栓６６の軸方向の長さが短くなり、また、圧入も簡単となる。なお、円周部の所定の位置での横孔加工による入口オリフィス６３の形成は変わるところはないため、実施例１と同様な作用効果を奏する。 [Effect of Example 2]
In the present embodiment, since the inlet orifice 63 is formed by a radial horizontal hole processing at a predetermined position on the circumferential portion which is not a notch portion of the orifice plate 60, the blind plug 66 for sealing the opening of the horizontal hole 66 is formed. The length in the axial direction is shortened, and press-fitting is easy. In addition, since the formation of the inlet orifice 63 by the horizontal hole machining at a predetermined position in the circumferential portion is not changed, the same effects as those of the first embodiment are obtained.

１燃料噴射弁
２噴射弁本体
３電磁弁
４噴射ノズル（ノズル）
５開閉弁機構
１６プレート室
１７制御ピストン
２０弁ボディ
３０電磁ソレノイド
３２ばね（付勢手段）
４３ニードル（ノズルニードル）
５０可動子
６０オリフィスプレート
６１圧力制御室
６２出口オリフィス
６３入口オリフィス
６５横孔
６６盲栓
６７、６８凹溝 1 Fuel Injection Valve 2 Injection Valve Body 3 Solenoid Valve 4 Injection Nozzle (Nozzle)
5 On-off valve mechanism 16 Plate chamber 17 Control piston 20 Valve body 30 Electromagnetic solenoid 32 Spring (biasing means)
43 Needle (Nozzle Needle)
50 Movable Element 60 Orifice Plate 61 Pressure Control Chamber 62 Exit Orifice 63 Inlet Orifice 65 Side Hole 66 Blind Plugs 67, 68 Concave Groove

Claims

An injection valve body including a nozzle and a nozzle needle;
Comprising an electromagnetic valve for intermittently injecting fuel from the injection valve body,
The electromagnetic valve includes an on-off valve mechanism including an electromagnetic solenoid, an urging means, and a mover driven by the magnetic force of the electromagnetic solenoid,
The on-off valve mechanism controls the back pressure of the pressure control chamber acting on the control piston interlocked with the nozzle needle by opening and closing the outlet orifice by a valve body provided on the mover,
In a fuel injection valve that opens and closes the nozzle needle to supply fuel,
The pressure control chamber is composed of a concave portion having a conical slope at the axial center of one end face of an orifice plate having a notch in a part of a substantially disc-shaped circumferential portion,
The outlet orifice facing in the axial direction is provided at the tip of the conical slope, and communicates with the pressure control chamber.
The inclined portion of the conical slope is provided with an inlet orifice for processing a horizontal hole in the radial direction,
The opening on the side opposite to the orifice of the side hole is closed by a blind plug,
A closed and independent fuel path is formed in the orifice plate integrally with the outlet orifice ;
The blind plug has a bottomed cylindrical cap structure,
At least the surface area of the cylindrical part is larger than the cross-sectional area of the bottom part,
The wall thickness forming the cylindrical portion has a predetermined thickness capable of elastic deformation,
By being press-fitted into the opening of the horizontal hole and receiving the internal pressure of the high-pressure fuel inside, the inner diameter is expanded, thereby increasing the contact surface pressure between the horizontal hole and the blind plug to self-seal (self-sealing) A fuel injection valve characterized by:

An injection valve body including a nozzle and a nozzle needle;
Comprising an electromagnetic valve for intermittently injecting fuel from the injection valve body,
The electromagnetic valve includes an on-off valve mechanism including an electromagnetic solenoid, an urging means, and a mover driven by the magnetic force of the electromagnetic solenoid,
The on-off valve mechanism controls the back pressure of the pressure control chamber acting on the control piston interlocked with the nozzle needle by opening and closing the outlet orifice by a valve body provided on the mover,
In a fuel injection valve that opens and closes the nozzle needle to supply fuel,
The pressure control chamber is composed of a concave portion having a conical slope at the axial center of one end face of an orifice plate having a notch in a part of a substantially disc-shaped circumferential portion,
The outlet orifice facing in the axial direction is provided at the tip of the conical slope, and communicates with the pressure control chamber.
The inclined portion of the conical slope is provided with an inlet orifice for processing a horizontal hole in the radial direction,
The opening on the side opposite to the orifice of the side hole is closed by a blind plug,
A closed and independent fuel path is formed in the orifice plate integrally with the outlet orifice;
The blind plug has a bottomed cylindrical cap structure,
The wall thickness forming the cylindrical portion has a uniform predetermined thickness that can be plastically deformed, or a predetermined thickness due to the formation of local concave grooves,
The opening of the horizontal hole is provided with a predetermined groove on its inner peripheral surface,
The blind plug is press-fitted into the opening of the lateral hole , and the inner diameter is expanded by receiving the internal pressure of the high-pressure fuel to form an overhang of plastic deformation, thereby constituting a retainer. Fuel injection valve.

The fuel injection valve according to claim 1 or 2 ,
2. The fuel injection valve according to claim 1, wherein the blind plug has the other end of the blind plug press-fitted into the opening of the lateral hole protruded from the end surface of the notch and is in contact with the inner wall surface of the valve body .

The fuel injection valve according to claim 1 or 2 ,
The inlet orifice is provided on the center side of the lateral hole facing in the radial direction formed at a predetermined position of a circumferential portion without a notch of the orifice plate,
The circumferential hole on the side opposite to the orifice of the horizontal hole is press-fitted until the blind plug is flush,
The fuel injection valve , wherein the orifice plate is accommodated in an inner wall surface of the valve body .