JP2007085245A

JP2007085245A - Common rail

Info

Publication number: JP2007085245A
Application number: JP2005274800A
Authority: JP
Inventors: Masayoshi Usui; 正佳臼井
Original assignee: Usui Kokusai Sangyo Kaisha Ltd
Current assignee: Usui Kokusai Sangyo Kaisha Ltd
Priority date: 2005-09-21
Filing date: 2005-09-21
Publication date: 2007-04-05

Abstract

<P>PROBLEM TO BE SOLVED: To provide a common rail in which the internal pressure fatigue strengths of a main pipe rail and a branch hole are increased by using a transformation induced plastic reinforced steel, reduced in overall weight and cost by using a rather small diameter, thin-walled, and long tube body for the main pipe rail, formed to be resistant to high pressure, and enabling a reduction in pressure during injection. <P>SOLUTION: In this common rail 13, the branch hole led to a flow passage is formed in the axial peripheral wall part of the main pipe rail 13-1 having a flow passage therein in its axial direction. A branch connection body is connected to the branch hole integrally with the main pipe rail 13-1 or through a separate joint member. A thin-walled small diameter pipe with t/d (t: wall thickness, d: outer diameter) of 0.2 to 0.35 for the main pipe rail. The pipe is of a transformation induced plastic reinforced steel. After processing is applied to the main pipe rail, retained austenite is produced by a heat treatment. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

本発明は、一般にディーゼル内燃機関の蓄圧燃料噴射システムにおける高圧燃料多岐管あるいはブロックレールなどのようなコモンレールに係り、特に内圧疲労強度を高めたコモンレールに関するものである。 The present invention generally relates to a common rail such as a high pressure fuel manifold or a block rail in a pressure accumulating fuel injection system of a diesel internal combustion engine, and more particularly to a common rail having increased internal pressure fatigue strength.

従来、この種のコモンレールとしては、本管レール側の周壁部に設けた内部の流通路に通ずる分岐孔部を外方に開口する受圧座面となし、該受圧座面附近の本管レールの外周部を囲繞するリング状の継手金具を使用し、端部に例えば先細円錐状の挫屈成形による拡径した分岐接続体（噴射管等）側の接続頭部のなす押圧座面を当接係合せしめ、該継手金具に突設した螺子壁部と予め分岐接続体側にスリーブワッシャを介して組込んだナットの螺合による前記接続頭部首下での押圧に伴って締着して接続する構造となしたものや、リング状の継手金具に替えて、筒状のスリーブニップルをそれぞれ凹凸嵌合螺着方式や、溶接、ろう付け等により直接本管レールの外周壁に取着し、分岐接続体側の接続頭部のなす押圧座面を本管レール側の受圧座面に当接係合せしめ、前記スリーブニップルに螺合するナットを締着して接続する構造となしたもの等が知られている（特許文献１、特許文献２、特許文献３等参照）。
特開平５−２４８５８３号公報特開平９−３２９２８７号公報特開平１０−２１３０４４号公報 Conventionally, as this type of common rail, there is a pressure receiving seat surface that opens outwardly to a branch hole portion that communicates with an internal flow passage provided in the peripheral wall portion on the main rail side, and the main rail near the pressure receiving seat surface is provided. Using a ring-shaped joint fitting that surrounds the outer periphery, the pressing seat surface formed by the connection head on the side of the branch connection body (injection pipe, etc.) that has been expanded by, for example, a tapered conical buckling is brought into contact with the end. Engage and connect with the screw wall part projecting from the joint fitting and the press under the neck of the connection head by screwing the nut assembled in advance on the branch connector side through the sleeve washer. Instead of ring-shaped joint fittings, cylindrical sleeve nipples are directly attached to the outer peripheral wall of the main rail by uneven fitting screwing, welding, brazing, etc. The pressure bearing surface formed by the connection head on the branch connector side is the pressure receiving seat on the main rail side. The abutment engagement tighten combined, such as those without a structure to connect fastening nut screwed to the sleeve nipple is known (see Patent Document 1, Patent Document 2, Patent Document 3).
JP-A-5-244853 Japanese Patent Laid-Open No. 9-329287 Japanese Patent Laid-Open No. 10-213044

上記した従来のコモンレールの場合は、当該レールに内圧が作用したとき分岐接続体（噴射管等）の流路の本管レールの開口内周縁部に最も大きな応力が発生し当該部位の内圧疲労強度が低下することを防止するため、厚肉化で対処してきた。しかし、この厚肉化により本管レールの外径が大きくなるため、コスト増、重量増を余儀なくされ、その重量増が熱容量の増大につながり、焼入れ−焼戻し等の熱処理において、本管レールは内面まで均一な金属組織が得られず、強度のバラツキを生じていた。
また、厚肉化によってレール外径が大きくなると、必然的に分岐接続体のサイズもそれに伴って大きくなるため、本管レールのみならず分岐接続体の重量も増し、コモンレール全体の重量および所要スペースの増加を招くといった問題もあった。 In the case of the conventional common rail described above, when internal pressure is applied to the rail, the largest stress is generated at the inner peripheral edge of the main rail opening in the flow path of the branch connection body (injection pipe, etc.), and the internal pressure fatigue strength of the corresponding portion Has been dealt with by increasing the wall thickness in order to prevent the decrease in the thickness. However, this increase in thickness increases the outer diameter of the main rail, which necessitates an increase in cost and weight, leading to an increase in heat capacity, and in the heat treatment such as quenching and tempering, the main rail has an inner surface. A uniform metal structure could not be obtained, resulting in variations in strength.
In addition, as the rail outer diameter increases due to thickening, the size of the branch connection inevitably increases accordingly, so the weight of not only the main rail but also the branch connection increases, and the weight of the entire common rail and the required space There was also the problem of inviting an increase.

本発明は従来技術の有する前記問題に鑑みてなされたものであり、変態誘起塑性型強度鋼を用い、本管レールおよび分岐孔の内圧疲労強度を高めるとともに、本管レールに比較的細径かつ薄肉で長尺の管体を用いることにより、コモンレール全体の重量の軽減、コストの低減をはかるとともに、高圧対応を可能にしかつ噴射時の圧力低下を少なくできるコモンレールを提供することを目的とするものである。 The present invention has been made in view of the above-mentioned problems of the prior art, and uses transformation-induced plastic-type strength steel to increase the internal pressure fatigue strength of the main rail and the branch hole, and has a relatively small diameter on the main rail. The purpose is to provide a common rail that uses a thin and long tube to reduce the weight and cost of the common rail as well as to enable high pressure response and reduce pressure drop during injection. It is.

本発明に係るコモンレールは、その軸芯方向内部に流通路を有する本管レールの軸方向の周壁部に前記流通路に通じる分岐孔を設け、本管レールと一体もしくは別体の継手部材を介して前記分岐孔に分岐接続体を接続して構成されるコモンレールにおいて、前記本管レールにｔ／ｄ（ｔ：肉厚、ｄ：外径）が０．２〜０．３５の薄肉細径管を用い、かつ該管を変態誘起塑性型強度鋼製とし、該本管レールに加工を施した後、熱処理により残留オーステナイトを生ぜしめたことを特徴とし、また、変態誘起塑性型強度鋼製の本管レールに熱処理により残留オーステナイトを生ぜしめた後、該本管レールに加工を施したことを特徴とするものである。
さらに、本発明に係るコモンレールは、前記本管レールに長尺の管体を用い、該管体をＵ字形に屈曲して形成された略平行する管体部分に前記複数の分岐孔を設け、該分岐孔に前記分岐接続体を接続した構成とすること、前記本管レールを、短尺の２本の管体を略平行に配置して構成するとともに、該２本の管体を接続配管に分岐接続して連通し、前記２本の管体に設けた前記複数の分岐孔に前記分岐接続体を接続した構成とすること、前記本管レールを、Ｕ字形に屈曲して形成された２本の管体を略環状に配置して構成するとともに、該２本の管体各々の両端末を接続配管に連通し、かつ該２本の管体に設けた前記複数の分岐孔に前記分岐接続体を接続した構成とすること、前記本管レールの外周壁部に前記別体からなる継手部材を外嵌した後、該本管レールの分岐孔部付近を塑性加工により少なくとも一部を拡径し本管レールと継手部材を相互に固着させたとすること等を特徴とするものである。さらにまた、本発明は、前記本管レールに内径がφ３〜φ６ｍｍ、肉厚が２〜３ｍｍの薄肉細径管を用いることを特徴とする。なお、前記分岐接続体の接続手段としては、ろう付けまたは溶接等を用いる。 The common rail according to the present invention is provided with a branch hole communicating with the flow passage in the axial peripheral wall portion of the main rail having a flow passage in the axial center thereof, and through a joint member that is integral with or separate from the main rail. In the common rail configured by connecting a branch connecting body to the branch hole, the thin main tube rail has a thin and thin diameter tube having a t / d (t: thickness, d: outer diameter) of 0.2 to 0.35. And the tube is made of transformation-induced plastic type strength steel, and after the main pipe rail is processed, residual austenite is produced by heat treatment, and the tube is made of transformation-induced plastic type strength steel. The main rail is characterized in that residual austenite is generated by heat treatment and then the main rail is processed.
Furthermore, the common rail according to the present invention uses a long tubular body for the main rail, and provides the plurality of branch holes in a substantially parallel tubular body portion formed by bending the tubular body into a U shape. The branch connection body is configured to be connected to the branch hole, and the main rail is configured by arranging two short pipe bodies substantially in parallel, and the two pipe bodies are connected to a connection pipe. 2 connected by branching connection, connecting the branch connection body to the plurality of branch holes provided in the two pipe bodies, and bending the main rail into a U-shape. The two pipe bodies are arranged in a substantially annular shape, and both ends of the two pipe bodies are connected to a connection pipe, and the branch is provided in the plurality of branch holes provided in the two pipe bodies. A connection body is connected, and a joint member made of the separate body is fitted on the outer peripheral wall of the main rail. After, it is characterized in that such a near branch hole portion of the main pipe rail at least a portion increased in diameter the main rail and the joint member is secured to each other by plastic working. Furthermore, the present invention is characterized in that a thin thin tube having an inner diameter of φ3 to φ6 mm and a thickness of 2 to 3 mm is used for the main rail. In addition, brazing, welding, etc. are used as a connection means of the said branch connection body.

本発明に係るコモンレールは上記のごとく、本管レールを変態誘起塑性型強度鋼製とし熱処理により残留オーステナイトを生ぜしめたことにより、本管レールおよび分岐孔の内圧疲労強度が大幅に高められるとともに、前記本管レールにｔ／ｄ（ｔ：肉厚、ｄ：外径）が０．２〜０．３５の薄肉細径管で高圧対応が可能である。また、本発明では、１本の薄肉細径管をＵ字形に屈曲して長尺の本管レールを構成したり、または短尺の２本の薄肉細径管を略平行に配置して長尺の本管レールを構成したり、あるいはＵ字形に屈曲して形成した２本の薄肉細径管を略環状に配置して長尺の本管レールを構成することにより、蓄圧体積を増加させることが可能となり噴射時の圧力低下を少なくできるという優れた効果を奏する。さらに、コモンレール全体の重量の軽減、コストの低減、省スペース化がはかられる。 As described above, the common rail according to the present invention is made of transformation-induced plastic-type strength steel and the retained austenite is generated by heat treatment, so that the internal pressure fatigue strength of the main rail and the branch hole is greatly increased. The main rail can be adapted to high pressure with a thin thin tube having a t / d (t: thickness, d: outer diameter) of 0.2 to 0.35. In the present invention, one thin thin tube is bent into a U shape to form a long main rail, or two short thin tubes are arranged substantially in parallel. To increase the pressure accumulation volume by constructing a long main rail by arranging two thin thin-diameter pipes formed in a substantially annular shape. This makes it possible to reduce the pressure drop during injection. Furthermore, the weight of the entire common rail can be reduced, costs can be reduced, and space can be saved.

本発明における変態誘起塑性型強度鋼は、近年、乗用車の足回りプレス成形部品の軽量化を目的として開発されたもので、残留オーステナイト（γ_Ｒ）のひずみ誘起変態（ＴＲＩＰ）を利用してプレス成形性を著しく改善したフエライト（α_ｆ）＋ベイナイト（α_ｂ）＋γ_Ｒ複合組織鋼［ＴＲＩＰ型Ｄｕａｌ−Ｐｈａｓｅ鋼、ＴＤＰ鋼］、およびベイニティックフェライト（α_ｂｆ）＋γ_Ｒ鋼［ＴＲＩＰ型ベイナイト鋼、ＴＢ鋼］である。
ここで変態誘起塑性とは、科学的に不安定な状態で存在するオーステナイト（γ）層が、力学的エネルギーの付加によりマルテンサイトへと変態する際に相伴う大きな伸びのことである。
すなわち、ＴＲＩＰ鋼とは、ある限定された組成の鋼において特定な熱処理を施すことにより、α層の粒界を中心に残留オーステナイトやベイナイト組織の混在した金属組織を得た鋼のことである。このような金属組織を有するＴＲＩＰ鋼の特徴としては、塑性変形能が高いこと、塑性加工によりマルテンサイト組織となるため強度が高くかつ硬くなることなどがあげられる。また、ＴＲＩＰ鋼の特徴としては表面から亀裂の発生そのものを抑える効果があるため、本管レール流通路内面から亀裂の発生が減少して内圧疲労強度が上昇することがあげられる。 The transformation-induced plastic type strength steel in the present invention has been developed in recent years for the purpose of reducing the weight of undercarriage press-formed parts of passenger cars, and presses using strain-induced transformation (TRIP) of retained austenite (γ _R ). Ferrite (α _f ) + bainite (α _b ) + γ _R composite structure steel [TRIP type Dual-Phase steel, TDP steel] and bainitic ferrite (α _bf ) + γ _R steel [TRIP type bainite] Steel, TB steel].
Here, the transformation-induced plasticity is a large elongation accompanying the transformation of an austenite (γ) layer that exists in a scientifically unstable state into martensite by the addition of mechanical energy.
That is, the TRIP steel is a steel obtained by performing a specific heat treatment on a steel having a limited composition to obtain a metal structure in which retained austenite and bainite structure are mixed around the grain boundary of the α layer. The characteristics of TRIP steel having such a metal structure include high plastic deformability and high strength and hardness because it becomes a martensite structure by plastic working. Further, TRIP steel has an effect of suppressing the occurrence of cracks from the surface itself, so that the occurrence of cracks from the inner surface of the main rail flow passage is reduced and the internal pressure fatigue strength is increased.

本発明に係るコモンレールは、このような特性を有する変態誘起塑性型強度鋼製であるので、鍛造時においては加工性が良く、所望の形状が得やすい。一方、特定の熱処理を行なわない場合（残留オーステナイト、ベイナイトが少ない場合）は、伸び、引張り強度共低く、容易に切削加工ができる。
また、変態誘起塑性型強度鋼は、局部的に変形した部分のオーステナイトが硬質なマルテンサイトに変態し、その部分を強化するという特性（ＴＲＩＰ現象）を有するので、この変態誘起塑性型強度鋼製のコモンレールの場合は、内圧が上昇してもある圧力から変態が進み、前記特性によりその部分が強化されて本管レールの破壊を阻止する抵抗力が生じるため耐圧性が向上する。 Since the common rail according to the present invention is made of transformation-induced plastic-type strength steel having such characteristics, workability is good during forging, and a desired shape is easily obtained. On the other hand, when specific heat treatment is not performed (when there is little retained austenite and bainite), the elongation and tensile strength are low, and cutting can be easily performed.
In addition, transformation induced plasticity strength steel has the property that the locally deformed austenite transforms into hard martensite and strengthens that portion (TRIP phenomenon). In the case of the common rail, the transformation proceeds from a certain pressure even if the internal pressure rises, and the portion is strengthened by the above characteristics, and a resistance force that prevents the breakage of the main rail is generated, so that the pressure resistance is improved.

本発明において、本管レールを細径化しかつ肉厚を薄肉化したのは、熱容量を小さくすることによって熱処理のバラツキを低減し、全体に均一な金属組織をるためである。ここで、本管レールのｔ／ｄ（ｔ：肉厚、ｄ：外径）を０．２〜０．３５としたのは、ｔ／ｄが０．２未満では薄肉すぎて強度が不足して耐圧強度が十分に得られず、他方、０．３５を超えると熱処理が本管レールの流通路の内周面まで均一に行われないためである。また、本発明において、前記本管レールに内径がφ３〜φ６ｍｍ、肉厚が２〜３ｍｍの薄肉細径管を用いることとしたのは、内径がφ３ｍｍ未満ではポンプからノズルへの燃料供給量が、流過抵抗が大きいために不足することが問題となり、他方、φ６ｍｍを超えると耐圧性を確保するために肉厚を増加させると、厚肉となることによりＴＲＩＰ鋼の熱処理時に本管レールの流通路の内周面まで均一な熱処理組織が得られないためである。また、肉厚が２ｍｍ未満では薄肉のため耐圧性が確保できず、他方、３ｍｍを超えると厚肉となりＴＲＩＰ鋼の熱処理時に均一な熱処理組織が得られないためである。 In the present invention, the main rail is reduced in diameter and the thickness is reduced in order to reduce the variation in heat treatment by reducing the heat capacity and to form a uniform metal structure throughout. Here, the t / d (t: wall thickness, d: outer diameter) of the main rail is set to 0.2 to 0.35 because if the t / d is less than 0.2, it is too thin and the strength is insufficient. This is because sufficient pressure resistance cannot be obtained, and on the other hand, if it exceeds 0.35, the heat treatment is not uniformly performed to the inner peripheral surface of the flow path of the main rail. In the present invention, a thin thin tube having an inner diameter of φ3 to φ6 mm and a wall thickness of 2 to 3 mm is used for the main rail because the fuel supply amount from the pump to the nozzle is less than φ3 mm. However, if the thickness is increased to ensure pressure resistance when the diameter exceeds 6 mm, the thickness of the main rail is increased during heat treatment of the TRIP steel. This is because a uniform heat treatment structure cannot be obtained up to the inner peripheral surface of the flow passage. In addition, if the thickness is less than 2 mm, the pressure resistance cannot be ensured because it is thin, and if it exceeds 3 mm, it becomes thick and a uniform heat treatment structure cannot be obtained during heat treatment of TRIP steel.

なお、本発明における熱処理は、本管レールを９５０℃に加熱し所定の時間保持してオーステナイト化し、その後３５０℃〜５００℃の間で所定の時間保持してオーステンパー処理を施す。このオーステンパー処理を施すことにより、α層の粒界を中心に残留オーステナイト（γ）層やベイナイト組織の混在した金属組織となる。
［実施例］ In the heat treatment in the present invention, the main rail is heated to 950 ° C. and held for a predetermined time to be austenitized, and thereafter austenitic treatment is performed by holding the temperature between 350 ° C. and 500 ° C. for a predetermined time. By performing this austempering treatment, a metal structure in which a retained austenite (γ) layer and a bainite structure are mixed around the grain boundary of the α layer is obtained.
[Example]

図１は本発明に係るコモンレールの第１実施例を示す概略図、図２は同じくコモンレールの第２実施例を示す概略図、図３は同じくコモンレールの第３実施例を示す概略図、図４は同じくコモンレールの第４実施例を示す噴射管接続部の断面図、図５は同じくコモンレールの第５実施例を示す噴射管接続部の断面図、図６は同じくコモンレールの第６実施例を示す噴射管接続部の断面図、図７は同じくコモンレールの第７実施例を示す噴射管接続部の断面図、図８は同じくコモンレールの第８実施例を示す噴射管接続部の断面図、図９は同じくコモンレールの第９実施例を示す噴射管接続部の断面図、図１０は同じくコモンレールの第１０実施例を示す噴射管接続部の断面図、図１１は同じくコモンレールの第１１実施例を示す噴射管接続部の断面図、図１２は同じくコモンレールの第１２実施例を示す噴射管接続部の断面図、図１３は同じくコモンレールの第１３実施例を示す噴射管接続部の断面図、図１４は同じくコモンレールの第１４実施例を示す噴射管接続部の断面図で、（Ａ）は縦断正面図、（Ｂ）は（Ａ）のイーイ線上の縦断側面図、図１５は同じくコモンレールの第１５実施例を示す噴射管接続部の断面図で、（Ａ）は縦断正面図、（Ｂ）は（Ａ）のローロ線上の縦断側面図であり、１１はＵ字形コモンレール、１１−１はＵ字形本管レール、１１−２は噴射管、１１−３はキャップ、１２は並設形コモンレール、１２−１はストレート形本管レール、１２−２は噴射管、１２−３は接続配管、１２−４は継手、１２−５はキャップ、１３は環状形コモンレール、１３−１はＵ字形本管レール、１３−２は噴射管、１３−３は継手、１４〜２５はコモンレール、１４−１〜２５−１は本管レール、１４−２〜２５−２は噴射管である。 1 is a schematic diagram showing a first embodiment of the common rail according to the present invention, FIG. 2 is a schematic diagram showing the second embodiment of the common rail, and FIG. 3 is a schematic diagram showing the third embodiment of the common rail. Fig. 5 is a sectional view of an injection pipe connecting portion showing a fourth embodiment of the common rail, Fig. 5 is a sectional view of an injection pipe connecting portion showing the fifth embodiment of the common rail, and Fig. 6 is a sixth embodiment of the common rail. FIG. 7 is a cross-sectional view of an injection pipe connecting portion showing a seventh embodiment of the common rail, and FIG. 8 is a cross-sectional view of an injection pipe connecting portion showing the eighth embodiment of the common rail. FIG. 10 is a sectional view of an injection pipe connecting portion showing a tenth embodiment of the common rail, and FIG. 11 is an sectional view of an injection pipe connecting portion showing the tenth embodiment of the common rail. Injection pipe connection 12 is a cross-sectional view of an injection pipe connection portion showing a twelfth embodiment of the common rail, FIG. 13 is a cross-sectional view of an injection pipe connection portion showing the thirteenth embodiment of the common rail, and FIG. 14A is a cross-sectional view of an injection pipe connecting portion showing a 14th embodiment, FIG. 15A is a vertical front view, FIG. 15B is a vertical side view on the line E of FIG. 15A, and FIG. It is sectional drawing of a pipe connection part, (A) is a longitudinal front view, (B) is a longitudinal side view on the roll line of (A), 11 is a U-shaped common rail, 11-1 is a U-shaped main rail, 11 -2 is an injection pipe, 11-3 is a cap, 12 is a side-by-side common rail, 12-1 is a straight main pipe rail, 12-2 is an injection pipe, 12-3 is a connection pipe, 12-4 is a joint, 12 -5 is a cap, 13 is an annular common rail, 1 -1 is a U-shaped main rail, 13-2 is an injection pipe, 13-3 is a joint, 14 to 25 are common rails, 14-1 to 25-1 are main rails, and 14-2 to 25-2 are injection pipes. It is.

本発明に係るコモンレールとしての本管レール１１−１〜２４−１は、変態誘起塑性型強度鋼製であって、熱処理により残留オーステナイトを生ぜしめたｔ／ｄが０．２〜０．３５の薄肉細径の金属管からなる。 Main rails 11-1 to 24-1 as common rails according to the present invention are made of transformation-induced plastic-type strength steel, and have a t / d of 0.2 to 0.35 in which residual austenite is generated by heat treatment. It consists of a thin and thin metal tube.

図１に示す第１実施例のコモンレールは、Ｕ字形コモンレール１１を例示したもので、このＵ字形コモンレール１１におけるＵ字形本管レール１１−１は、前記したごとく変態誘起塑性型強度鋼製であって、熱処理により残留オーステナイトを生ぜしめたｔ／ｄが０．２〜０．３５の薄肉細径の金属管からなる１本の長尺の金属管をＵ字形に屈曲して形成したＵ字形本管レール１１−１の略平行する金属管部分１１−１ａに前記複数の分岐孔が設けられ、該分岐孔に噴射管１１−２を接続して構成したものである。なお、Ｕ字形本管レール１１−１の両端部はキャップ１１−３にて密閉する。なお、ポンプからの供給管は省略してある。 The common rail of the first embodiment shown in FIG. 1 is an example of a U-shaped common rail 11, and the U-shaped main rail 11-1 in the U-shaped common rail 11 is made of transformation-induced plastic type strength steel as described above. A U-shaped book formed by bending one long metal tube made of a thin and thin metal tube having a t / d of 0.2 to 0.35 and having retained austenite by heat treatment into a U shape. The plurality of branch holes are provided in the substantially parallel metal pipe portion 11-1a of the pipe rail 11-1, and the injection pipe 11-2 is connected to the branch holes. Note that both ends of the U-shaped main rail 11-1 are sealed with caps 11-3. The supply pipe from the pump is omitted.

図２に示すコモンレール１２は、並設形コモンレールを例示したもので、この並設形コモンレールにおけるストレート形本管レール１２−１は、同じく変態誘起塑性型強度鋼製であって、熱処理により残留オーステナイトを生ぜしめたｔ／ｄが０．２〜０．３５の薄肉細径の金属管で作製した同一長さの短尺の２本の金属管に前記複数の分岐孔を設けてストレート形本管レール１２−１を構成し、この２本のストレート形本管レール１２−１の一端をポンプからの供給管が接続された継手１２−４にて接続配管１２−３に接続するとともに、他端をキャップ１２−５にて密閉し、各ストレート形本管レール１２−１に設けられた分岐孔に噴射管１２−２を接続して構成したものである。 The common rail 12 shown in FIG. 2 is an example of a side-by-side common rail, and the straight main rail 12-1 in this side-by-side common rail is also made of transformation-induced plastic-type strength steel and is retained austenite by heat treatment. A straight main rail provided with a plurality of branch holes in two short metal pipes of the same length made of a thin and thin metal pipe having a t / d of 0.2 to 0.35 that gives rise to 12-1 is configured, and one end of the two straight main rails 12-1 is connected to a connection pipe 12-3 by a joint 12-4 to which a supply pipe from a pump is connected, and the other end is connected. Sealed with a cap 12-5, the injection pipe 12-2 is connected to a branch hole provided in each straight main rail 12-1.

図３に示すコモンレール１３は、略環状形コモンレールを例示したもので、この略環状形コモンレールにおけるＵ字形本管レール１３−１は、同じく変態誘起塑性型強度鋼製であって、熱処理により残留オーステナイトを生ぜしめたｔ／ｄが０．２〜０．３５の薄肉細径の金属管をＵ字形に屈曲して形成したＵ字形本管レールを２本用い、このＵ字形本管レールの各両端末をポンプからの供給管が接続された継手１３−３にて接続して環状となし、各Ｕ字形本管レールに設けられた分岐孔に噴射管１３−２を接続して構成したものである。 The common rail 13 shown in FIG. 3 is an example of a substantially annular common rail, and the U-shaped main rail 13-1 in the substantially annular common rail is also made of transformation-induced plastic-type strength steel and is retained austenite by heat treatment. Using two U-shaped main rails formed by bending a thin and thin metal tube with a t / d of 0.2 to 0.35 into a U shape, each of the U-shaped main rails The terminal is connected by a joint 13-3 to which a supply pipe from a pump is connected to form a ring, and the injection pipe 13-2 is connected to a branch hole provided in each U-shaped main rail. is there.

図４に示すコモンレール１４は、同じく変態誘起塑性型強度鋼製であって、熱処理により残留オーステナイトを生ぜしめたｔ／ｄが０．２〜０．３５の薄肉細径の本管レール１４−１の流通路１４−１ａの軸方向の周壁部に間隔を保持して外方に開口する周面を受圧座面１４−１ｃとなす分岐孔１４−１ｂを前記流通路１４−１ａに連通して設けてなるものである。
一方、噴射管１４−２は、その内部に前記流通路１４−１ａに通ずる流路１４−２ａを有してその端部に先細円錐状の挫屈成形による拡径した接続頭部１４−２ｂのなす押圧座面１４−２ｃを設けてなるものである。
この図４に示すコモンレールの本管レール１４−１と噴射管１４−２の接続方式は、筒状スリーブニップル１４−３を本管レール１４−１の径方向で外方に突出するようにろう付けまたは溶接あるいは凹凸嵌合螺着方式等により直接本管レール１４−１の外周壁に取着し、噴射管１４−２側の押圧座面１４−２ｃを本管レール１４−１側の受圧座面１４−１ｃに当接係合せしめ、前記スリーブニップル１４−３に螺合するナット１４−４を締付けて接続する方式となしたものである。 The common rail 14 shown in FIG. 4 is also made of transformation-induced plastic-type strength steel, and has a thin and thin main rail 14-1 having a t / d of 0.2 to 0.35 that generates retained austenite by heat treatment. A branch hole 14-1b is formed in communication with the flow passage 14-1a. The branch hole 14-1b forms a pressure receiving seat surface 14-1c with a circumferential surface opening outward while maintaining a space in the axial peripheral wall portion of the flow passage 14-1a. It is provided.
On the other hand, the injection pipe 14-2 has a flow path 14-2a that communicates with the flow passage 14-1a therein, and has a connecting head 14-2b whose diameter is increased by a tapered conical buckling at the end thereof. A pressing seat surface 14-2c is provided.
The connection method of the main rail 14-1 and the injection tube 14-2 of the common rail shown in FIG. 4 is such that the cylindrical sleeve nipple 14-3 protrudes outward in the radial direction of the main rail 14-1. It is directly attached to the outer peripheral wall of the main rail 14-1 by attaching or welding or an uneven fitting screwing method, etc., and the pressure seating surface 14-2c on the side of the injection pipe 14-2 is received by the pressure on the main rail 14-1 side. This is a system in which a seat 14-1c is abutted and engaged, and a nut 14-4 that is screwed into the sleeve nipple 14-3 is tightened and connected.

図５に示すコモンレール１５は、本管レール１５−１の周壁部に設ける受圧座面１５−１ｃ付き分岐孔１５−１ｂの大きさが異なる以外は、前記図４に示すコモンレールと実質的に同じ構成となしたもので、本管レール１５−１は同じく変態誘起塑性型強度鋼製であって、熱処理により残留オーステナイトを生ぜしめたｔ／ｄが０．２〜０．３５の薄肉細径の本管レール１５−１の流通路１５−１ａの軸方向の周壁部に間隔を保持して外方に開口する周面を受圧座面１５−１ｃとなす分岐孔１５−１ｂを前記流通路１５−１ａに連通して設け、噴射管１５−２側の押圧座面１５−２ｃを本管レール１５−１側の受圧座面１５−１ｃに当接係合せしめ、前記本管レール１５−１の外周壁にろう付けまたは溶接等により取着した筒状スリーブニップル１５−３に螺合するナット１５−４を締付けて接続構成したものである。１５−２ａは流路、１５−２ｂは接続頭部である。 The common rail 15 shown in FIG. 5 is substantially the same as the common rail shown in FIG. 4 except that the size of the branch hole 15-1b with the pressure receiving seat surface 15-1c provided on the peripheral wall portion of the main rail 15-1 is different. The main rail 15-1 is made of transformation-induced plastic-type strength steel, and has a thin and thin diameter t / d of 0.2 to 0.35, which produced residual austenite by heat treatment. The flow passage 15 has a branch hole 15-1b that forms a pressure receiving seat surface 15-1c with a circumferential surface that opens outward while maintaining a space in the axial peripheral wall portion of the flow passage 15-1a of the main rail 15-1. 1a, the pressure seat surface 15-2c on the injection tube 15-2 side is brought into contact with and engaged with the pressure receiving seat surface 15-1c on the main rail 15-1 side, and the main rail 15-1 A cylindrical sleeve attached to the outer peripheral wall of the steel by brazing or welding It is obtained by connection configuration by tightening the nut 15-4 screwed to Le 15-3. 15-2a is a flow path, and 15-2b is a connection head.

図６に示すコモンレール１６は、締結用ナットに袋ナット１６−４を用い、かつワッシャ１６−５を組込んで締付ける方式を採用した以外は、前記図５に示すコモンレールと実質的に同じ構成となしたもので、本管レール１６−１は同じく変態誘起塑性型強度鋼製であって、熱処理により残留オーステナイトを生ぜしめたｔ／ｄが０．２〜０．３５の薄肉細径の本管レール１６−１の流通路１６−１ａの軸方向の周壁部に間隔を保持して外方に開口する周面を受圧座面１６−１ｃとなす分岐孔１６−１ｂを前記流通路１６−１ａに連通して設け、噴射管１６−２側の押圧座面１６−２ｃを本管レール１６−１側の受圧座面１６−１ｃに当接係合せしめ、噴射管１６−２の接続頭部１６−２ｂの背面側に組込んだをワッシャ１６−５を、前記本管レール１６−１の外周壁にろう付けまたは溶接等により取着した筒状スリーブニップル１６−３に螺合する袋ナット１６−４にて締付けて接続構成したものである。１６−２ａは流路である。 The common rail 16 shown in FIG. 6 has substantially the same configuration as the common rail shown in FIG. 5 except that a cap nut 16-4 is used as a fastening nut and a washer 16-5 is incorporated and tightened. The main rail 16-1 is also made of transformation-induced plastic-type strength steel, and has a thin thin main tube with a t / d of 0.2 to 0.35 that has produced retained austenite by heat treatment. A branch hole 16-1b is formed in the flow passage 16-1a. The branch hole 16-1b forms a pressure receiving seat surface 16-1c with a circumferential surface opening outward while maintaining a space in the axial peripheral wall portion of the flow passage 16-1a of the rail 16-1. The pressure bearing surface 16-2c on the injection tube 16-2 side is brought into contact with and engaged with the pressure receiving seat surface 16-1c on the main rail 16-1 side, and the connection head of the injection tube 16-2 is provided. The washer 16-5 incorporated in the back side of 16-2b Which are connected configured fastened at the cap nut 16-4 screwed to the tubular sleeve nipple 16-3 was attached by brazing or welding to the outer peripheral wall of the rail 16-1. 16-2a is a flow path.

図７に示すコモンレール１７は、前記図５に示すコモンレール１５における筒状スリーブニップル１５−３に替えて、本管レール１７−１の外周部を囲繞するリング状の継手金具１７−３を用いた以外は、図５に示すコモンレール１５と実質的に同じ構成となしたもので、本管レール１７−１は同じく変態誘起塑性型強度鋼製であって、熱処理により残留オーステナイトを生ぜしめたｔ／ｄが０．２〜０．３５の薄肉細径の本管レール１７−１の流通路１７−１ａの軸方向の周壁部に間隔を保持して外方に開口する周面を受圧座面１７−１ｃとなす分岐孔１７−１ｂを前記流通路１７−１ａに連通して設け、噴射管１７−２側の押圧座面１７−２ｃを本管レール１７−１側の受圧座面１７−１ｃに当接係合せしめ、前記本管レール１７−１の外嵌固定したリング状の継手金具１７−３に螺合するナット１７−４を締付けて接続構成したものである。１７−２ａは流路、１７−２ｂは接続頭部である。 The common rail 17 shown in FIG. 7 uses a ring-shaped fitting 17-3 surrounding the outer periphery of the main rail 17-1, instead of the cylindrical sleeve nipple 15-3 in the common rail 15 shown in FIG. The main rail 17-1 is made of transformation-induced plastic-type strength steel, and the residual austenite is generated by heat treatment, except that the common rail 15 shown in FIG. The pressure-receiving seat surface 17 is a circumferential surface that opens outward while maintaining a space in the axial peripheral wall portion of the flow passage 17-1a of the thin-walled thin main rail 17-1 having d of 0.2 to 0.35. Branch passage 17-1b that is connected to the flow passage 17-1a, and the pressure seat surface 17-2c on the injection tube 17-2 side is provided with the pressure receiving seat surface 17-1c on the main rail 17-1 side. To the main rail 17-1. Which are connected constitute a nut 17-4 screwed into a ring-shaped joint fitting 17-3 sleeving fixed tightened. 17-2a is a flow path, and 17-2b is a connection head.

図８に示すコモンレール１８は、前記図５に示すコモンレール１５における本管レールに設ける分岐孔１５−１ｂの部分を円錐状で内方に突設した以外は、図５に示すコモンレール１５と実質的に同じ構成となしたもので、本管レール１８−１は同じく変態誘起塑性型強度鋼製であって、熱処理により残留オーステナイトを生ぜしめたｔ／ｄが０．２〜０．３５の薄肉細径の本管レール１８−１の流通路１８−１ａの軸方向の周壁部に間隔を保持して該本管レール１８−１の内壁を内方に突出させて截頭円錐状の突出部１８−１ｄを形成し、該突出部１８−１ｄに外方に開口する周面を受圧座面１８−１ｃとなすテーパ状に開口した分岐孔１８−１ｂを前記流通路１８−１ａに連通して設け、噴射管１８−２側の押圧座面１８−２ｃを本管レール１８−１側の受圧座面１８−１ｃに当接係合せしめ、前記本管レール１８−１の外周壁にろう付けまたは溶接等により取着した筒状スリーブニップル１８−３に螺合するナット１８−４を締付けて接続構成したものである。１８−２ａは流路、１８−２ｂは接続頭部である。 The common rail 18 shown in FIG. 8 is substantially the same as the common rail 15 shown in FIG. 5 except that the branch hole 15-1b provided in the main rail of the common rail 15 shown in FIG. The main rail 18-1 is also made of transformation-induced plastic-type strength steel, and has a thin and thin thickness t / d of 0.2 to 0.35 that generates retained austenite by heat treatment. The inner wall of the main rail 18-1 protrudes inward while maintaining a gap in the axial peripheral wall portion of the flow passage 18-1a of the main pipe rail 18-1 having a diameter, and the frustoconical protrusion 18 is formed. -1d is formed, and a branch hole 18-1b having a taper-like shape is formed in communication with the flow passage 18-1a. The press seat surface 18-2c on the injection pipe 18-2 side is connected to the main pipe Abutting and engaging with the pressure receiving seat surface 18-1c on the side of the rail 18-1, and screwing into a cylindrical sleeve nipple 18-3 attached to the outer peripheral wall of the main rail 18-1 by brazing or welding. The nut 18-4 is tightened and connected. 18-2a is a flow path, and 18-2b is a connection head.

図９に示すコモンレール１９は、前記図６に示すコモンレール１６における本管レールに設ける分岐孔１６−１ｂの部分を円錐状で内方に突設した以外は、図６に示すコモンレール１６と実質的に同じ構成となしたもので、本管レール１９−１は同じく変態誘起塑性型強度鋼製であって、熱処理により残留オーステナイトを生ぜしめたｔ／ｄが０．２〜０．３５の薄肉細径の本管レール１９−１の流通路１９−１ａの軸方向の周壁部に間隔を保持して該本管レール１９−１の内壁を内方に突出させて截頭円錐状の突出部１９−１ｄを形成し、該突出部１９−１ｄに外方に開口する周面を受圧座面１９−１ｃとなすテーパ状に開口した分岐孔１９−１ｂを前記流通路１９−１ａに連通して設け、噴射管１９−２側の押圧座面１９−２ｃを本管レール１９−１側の受圧座面１９−１ｃに当接係合せしめ
、噴射管１９−２の接続頭部１９−２ｂの背面側に組込んだをワッシャ１９−５を、前記本管レール１９−１の外周壁にろう付けまたは溶接等により取着した筒状スリーブニップル１９−３に螺合する袋ナット１９−４にて締付けて接続構成したものである。１９−２ａは流路である。 The common rail 19 shown in FIG. 9 is substantially the same as the common rail 16 shown in FIG. 6 except that the branch hole 16-1b provided in the main rail of the common rail 16 shown in FIG. The main rail 19-1 is also made of transformation-induced plastic-type strength steel, and is thin and thin with a t / d of 0.2 to 0.35 that generates retained austenite by heat treatment. The inner wall of the main rail 19-1 protrudes inward while maintaining a space in the axial peripheral wall portion of the flow passage 19-1a of the main pipe rail 19-1. -1d is formed, and a branch hole 19-1b having a taper-like shape is formed in communication with the flow passage 19-1a. The press seat surface 19-2c on the injection pipe 19-2 side is connected to the main pipe The washer 19-5 is abutted and engaged with the pressure-receiving seat surface 19-1c on the side of the barrel 19-1 and assembled on the back side of the connection head portion 19-2b of the injection pipe 19-2. -1 and tightened with a cap nut 19-4 screwed to a cylindrical sleeve nipple 19-3 attached by brazing or welding to the outer peripheral wall. 19-2a is a flow path.

図１０に示すコモンレール２０は、前記図７に示すコモンレール１７における本管レールに設ける分岐孔１７−１ｂの部分を内方に突設した以外は、図７に示すコモンレール１７と実質的に同じ構成となしたもので、本管レール２０−１は同じく変態誘起塑性型強度鋼製であって、熱処理により残留オーステナイトを生ぜしめたｔ／ｄが０．２〜０．３５の薄肉細径の本管レール２０−１の流通路２０−１ａの軸方向の周壁部に間隔を保持して該本管レール２０−１の内壁を内側に突出させた突出部２０−１ｄを形成し、該突出部２０−１ｄに外方に開口する周面を受圧座面２０−１ｃとなすテーパ状に開口した分岐孔２０−１ｂを前記流通路２０−１ａに連通して設け、噴射管２０−２側の押圧座面２０−２ｃを本管レール２０−１側の受圧座面２０−１ｃに当接係合せしめ、前記本管レール２０−１の外嵌固定したリング状の継手金具２０−３に螺合するナット２０−４を締付けて接続構成したものである。２０−２ａは流路、２０−２ｂは接続頭部である。 The common rail 20 shown in FIG. 10 has substantially the same configuration as the common rail 17 shown in FIG. 7 except that the branch hole 17-1b provided in the main rail in the common rail 17 shown in FIG. The main rail 20-1 is also made of transformation-induced plastic-type strength steel, and has a thin and thin diameter with a t / d of 0.2 to 0.35, which produced residual austenite by heat treatment. A protruding portion 20-1d is formed in which the inner wall of the main rail 20-1 protrudes inward while maintaining a gap in the axial peripheral wall portion of the flow passage 20-1a of the pipe rail 20-1. A branch hole 20-1b having a tapered shape in which a circumferential surface that opens outwardly to 20-1d serves as a pressure receiving seat surface 20-1c is provided in communication with the flow passage 20-1a, and is provided on the injection pipe 20-2 side. The pressing seat 20-2c is received on the main rail 20-1 side. Tighten combined contact engagement with the seat surface 20-1C, which are connected structure fitted fixed by tightening the nut 20-4 screwed into a ring-shaped joint fitting 20-3 of the main rail 20-1. 20-2a is a flow path, and 20-2b is a connection head.

図１１に示すコモンレール２１は、前記図８に示すコモンレール１８における本管レールに設ける受圧座面１８−１ｃの部分を円錐状で外方に突設した以外は、図８に示すコモンレール１８と実質的に同じ構成となしたもので、本管レール２１−１は同じく変態誘起塑性型強度鋼製であって、熱処理により残留オーステナイトを生ぜしめたｔ／ｄが０．２〜０．３５の薄肉細径の本管レール２１−１の流通路２１−１ａの軸方向の周壁部に間隔を保持して、流通路２１−１ａに連通するテーパ状の分岐孔２１−１ｂを設け、かつ外側には截頭円錐状の受圧座面２１−１ｃを外方に突設し、噴射管２１−２の端部に形成した当該噴射管より大径の拡径部からなる接続頭部２１−２ｂのなす外側に広がる押圧座面を２１−２ｃを本管レール２１−１側の受圧座面２１−１ｃに当接係合せしめ、前記本管レール２１−１の外周壁にろう付けまたは溶接等により取着した筒状スリーブニップル２１−３に螺合するナット２１−４を締付けて接続構成したものである。２１−２ａは流路である。 The common rail 21 shown in FIG. 11 is substantially the same as the common rail 18 shown in FIG. 8 except that the pressure receiving seat surface 18-1c provided on the main rail in the common rail 18 shown in FIG. The main rail 21-1 is also made of transformation-induced plastic-type strength steel, and has a thin wall thickness t / d of 0.2 to 0.35 that generates residual austenite by heat treatment. A tapered branch hole 21-1b communicating with the flow passage 21-1a is provided on the outer peripheral wall portion in the axial direction of the flow passage 21-1a of the main rail 21-1 having a small diameter. Has a frustoconical pressure-receiving seat surface 21-1c projecting outward, and the connecting head 21-2b, which is formed at the end of the injection pipe 21-2 and has a larger diameter than the injection pipe. 21-2c is the main seat rail 21- A nut 21-4 that engages with the pressure-receiving seat surface 21-1c on the side and is screwed into a cylindrical sleeve nipple 21-3 attached to the outer peripheral wall of the main rail 21-1 by brazing or welding. The connection structure is tightened. 21-2a is a flow path.

図１２に示すコモンレール２２は、前記図９に示すコモンレール１９における本管レールに設ける受圧座面１９−１ｃの部分を円錐状で外方に突設した以外は、図９に示すコモンレール１９と実質的に同じ構成となしたもので、本管レール２２−１は同じく変態誘起塑性型強度鋼製であって、熱処理により残留オーステナイトを生ぜしめたｔ／ｄが０．２〜０．３５の薄肉細径の本管レール２２−１の流通路２２−１ａの軸方向の周壁部に間隔を保持して、流通路２２−１ａに連通するテーパ状の分岐孔２２−１ｂを設け、かつ外側には截頭円錐状の受圧座面
２２−１ｃを外方に突設し、噴射管２２−２の端部に形成した当該噴射管より大径の拡径部からなる接続頭部２２−２ｂのなす外側に広がる押圧座面を２２−２ｃを本管レール２２−１側の受圧座面２２−１ｃに当接係合せしめ、噴射管２２−２の接続頭部２２−２ｂの背面側に組込んだスリーブワッシャ２２−５を、前記本管レール２２−１の外周壁にろう付けまたは溶接等により取着した筒状スリーブニップル２２−３に螺合する袋ナット２２−４にて締付けて接続構成したものである。２２−２ａは流路である。 The common rail 22 shown in FIG. 12 is substantially the same as the common rail 19 shown in FIG. 9 except that the pressure receiving seat surface 19-1c provided on the main rail in the common rail 19 shown in FIG. The main rail 22-1 is also made of transformation-induced plastic-type strength steel, and has a thin wall thickness of t / d of 0.2 to 0.35 that generates residual austenite by heat treatment. A tapered branch hole 22-1b that communicates with the flow passage 22-1a is provided on the outer peripheral wall portion of the small diameter main rail 22-1 in the axial direction of the flow passage 22-1a. Has a frustoconical pressure-receiving seat surface 22-1c projecting outward, and a connecting head 22-2b having a larger diameter portion than the injection pipe formed at the end of the injection pipe 22-2. The pressing seat surface 22-2c that extends outward is connected to the main rail 22- The sleeve washer 22-5, which is brought into contact with and engaged with the pressure-receiving seat surface 22-1c on the side and incorporated on the back side of the connection head portion 22-2b of the injection tube 22-2, is attached to the outer periphery of the main rail 22-1. It is configured to be connected by tightening with a cap nut 22-4 that is screwed into a cylindrical sleeve nipple 22-3 attached to the wall by brazing or welding. 22-2a is a flow path.

図１３に示すコモンレール２３は、前記図１０に示すコモンレール２０における本管レールに設ける受圧座面２２−１ｃの部分を円錐状で外方に突設した以外は、図１０に示すコモンレール２０と実質的に同じ構成となしたもので、本管レール２３−１は同じく変態誘起塑性型強度鋼製であって、熱処理により残留オーステナイトを生ぜしめたｔ／ｄが０．２〜０．３５の薄肉細径の本管レール２３−１の流通路２３−１ａの軸方向の周壁部に間隔を保持して、流通路２３−１ａに連通するテーパ状の分岐孔２３−１ｂを設け、かつ外側には截頭円錐状の受圧座面２３−１ｃを外方に突設し、噴射管２３−２の端部に形成した当該噴射管より大径の拡径部からなる接続頭部２３−２ｂのなす外側に広がる押圧座面を２３−２ｃを本管レール２３−１側の受圧座面２３−１ｃに当接係合せしめ、前記本管レール２３−１の外嵌固定したリング状の継手金具２３−３に螺合するナット２３−４を締付けて接続構成したものである。２３−２ａは流路である。 The common rail 23 shown in FIG. 13 is substantially the same as the common rail 20 shown in FIG. 10 except that the pressure receiving seat surface 22-1c provided on the main rail in the common rail 20 shown in FIG. The main rail 23-1 is also made of transformation-induced plastic-type strength steel, and has a thin wall thickness of t / d of 0.2 to 0.35 that generates residual austenite by heat treatment. A tapered branch hole 23-1b communicating with the flow passage 23-1a is provided on the outer peripheral wall portion in the axial direction of the flow passage 23-1a of the narrow main rail 23-1, and is provided on the outside. Has a frustoconical pressure receiving seat surface 23-1c projecting outward, and the connecting head 23-2b, which is formed at the end of the injection pipe 23-2 and has a larger diameter than the injection pipe. 23-2c the main seat rail 2 -1 side pressure-receiving seat surface 23-1c is abutted and engaged, and a nut 23-4 that is screwed into a ring-shaped joint fitting 23-3 that is externally fixed to the main rail 23-1 is tightened. It is a thing. 23-2a is a flow path.

図１４に示すコモンレール２４は、同じく変態誘起塑性型強度鋼製であって、熱処理により残留オーステナイトを生ぜしめたｔ／ｄが０．２〜０．３５の薄肉細径の本管レール２４−１の外周壁部にリング状の継手金具２４−３を外嵌した後、該本管レール２４−１の周壁部に設けた内部の流通路に２４−１ａに通ずる分岐孔２４−１ｂの付近の両側をプレス加工により押圧して当該本管レール２４−１を拡径させて前記リング状の継手金具２４−３を該本管レール２４−１に圧嵌させる。この時、分岐孔２４−１ｂの流通路開口端部は、同図（Ｂ）に示すように流通路に２４−１ａの内側に突出し、その周縁には圧縮応力が残留して内圧疲労強度を向上させている。噴射管２４−２の接続に際しては、該噴射管２４−２の端部に形成した接続頭部２４−２ｂのなす外側に広がる押圧座面を２４−２ｃを本管レール２４−１側の受圧座面２４−１ｃに当接係合せしめ、噴射管２４−２の接続頭部２４−２ｂの背面側に組込んだをワッシャ２４−５を、前記本管レール２４−１の外周壁に取着した筒状スリーブニップル２４−３に螺合する袋ナット２４−４にて締付けて接続構成したものである。２４−２ａは流路である。 The common rail 24 shown in FIG. 14 is also made of transformation-induced plastic-type strength steel, and has a thin and thin main rail 24-1 having a t / d of 0.2 to 0.35, which generates retained austenite by heat treatment. After fitting the ring-shaped joint fitting 24-3 on the outer peripheral wall portion of the main rail 24-1, the inner flow passage provided in the peripheral wall portion of the main rail 24-1 near the branch hole 24-1b leading to 24-1a. Both sides are pressed by press working to expand the diameter of the main rail 24-1, and the ring-shaped joint fitting 24-3 is press-fitted to the main rail 24-1. At this time, the flow passage opening end portion of the branch hole 24-1b protrudes inside the flow passage 24-1a as shown in FIG. It is improving. When connecting the injection pipe 24-2, the pressure seating surface that extends outward from the connection head 24-2b formed at the end of the injection pipe 24-2 is used as the pressure receiving surface on the main rail 24-1 side. The washer 24-5, which is abutted and engaged with the seating surface 24-1c and is assembled on the back side of the connection head 24-2b of the injection pipe 24-2, is attached to the outer peripheral wall of the main rail 24-1. It is configured to be tightened and connected with a cap nut 24-4 that is screwed into the worn cylindrical sleeve nipple 24-3. 24-2a is a flow path.

図１５に示すコモンレール２５は、同じく変態誘起塑性型強度鋼製であって、熱処理により残留オーステナイトを生ぜしめたｔ／ｄが０．２〜０．３５の薄肉細径の本管レール２５−１の分岐孔２５−１ｂの外側開口端部付近の断面形状が異なる以外は、図１４に示すものと実質的に同じ構成である。すなわち、本管レール２５−１の外周壁部にリング状の継手金具２５−３を外嵌した後、該本管レール２５−１の周壁部に設けた内部の流通路に２５−１ａに通ずる分岐孔２５−１ｂの外側開口端部付近をプレス加工により押圧して当該本管レール２５−１を拡径させて前記リング状の継手金具２５−３を該本管レール２５−１に圧嵌させる。この時、分岐孔２５−１ｂの流通路開口端部は、同図（Ｂ）に示すように流通路に２５−１ａの内側に突出し、その周縁には圧縮応力が残留して内圧疲労強度を向上させている。噴射管２５−２の接続に際しては、該噴射管２５−２の端部に形成した接続頭部２５−２ｂのなす外側に広がる押圧座面を２５−２ｃを本管レール２５−１側の受圧座面２５−１ｃに当接係合せしめ、噴射管２５−２の接続頭部２５−２ｂの背面側に組込んだワッシャ２５−５を、前記本管レール２５−１の外周壁に取着したリング状の継手金具２５−３に螺合する袋ナット２５−４にて締付けて接続構成したものである。２５−２ａは流路である。 The common rail 25 shown in FIG. 15 is also made of transformation-induced plastic-type strength steel, and has a thin and thin main rail 25-1 having a t / d of 0.2 to 0.35, which has produced retained austenite by heat treatment. 14 is substantially the same as that shown in FIG. 14 except that the cross-sectional shape near the outer opening end of the branch hole 25-1b is different. That is, after fitting the ring-shaped joint metal fitting 25-3 on the outer peripheral wall portion of the main rail 25-1, it leads to the internal flow passage provided in the peripheral wall portion of the main rail 25-1 to 25-1a. The vicinity of the outer opening end of the branch hole 25-1b is pressed by press working to expand the diameter of the main rail 25-1, and the ring-shaped joint fitting 25-3 is press-fitted to the main rail 25-1. Let At this time, the flow passage opening end of the branch hole 25-1b protrudes to the inside of the flow passage 25-1a as shown in FIG. It is improving. When connecting the injection pipe 25-2, the pressure bearing surface 25-2c extending outside the connection head 25-2b formed at the end of the injection pipe 25-2 is used as the pressure receiving pressure on the main rail 25-1 side. A washer 25-5 which is brought into contact with and engaged with the seating surface 25-1c and is installed on the back side of the connection head portion 25-2b of the injection pipe 25-2 is attached to the outer peripheral wall of the main rail 25-1. The ring-shaped joint metal fitting 25-3 is tightened with a cap nut 25-4 that is screwed together to be connected. 25-2a is a flow path.

本発明に係るコモンレールは、本管レールを変態誘起塑性型強度鋼製とし、かつ熱処理により残留オーステナイトを生ぜしめ、本管レールおよび分岐孔の内圧疲労強度を高めるとともに、比較的細径かつ薄肉で高圧対応を可能とし、また、長尺の前記管体を用い、本管レールをＵ字形に屈曲して構成したコモンレール、２本の直線上管体を平行に配置して構成した並設型コモンレール、２本のＵ字形管体を接続して構成した環状型コモンレールを製作することができるので、軽量でコンパクト化できるのみならず、蓄圧体積を増加させることができることにより噴射時の圧力を少なくできるという優れた効果を奏し、その用途は、ディーゼル内燃機関におけるコモンレール以外の高圧燃料多岐管等にも適用可能である。 The common rail according to the present invention is made of transformation-induced plastic-type strength steel, and the retained austenite is generated by heat treatment to increase the internal pressure fatigue strength of the main rail and the branch hole, and is relatively thin and thin. A common rail that can be used for high pressures and that is constructed by using the long tubular body and bending the main rail into a U-shape and arranging two straight tubes in parallel. Since an annular common rail constructed by connecting two U-shaped tubes can be manufactured, not only is it lightweight and compact, but also the pressure during injection can be reduced by increasing the pressure accumulation volume. The use of the high-pressure fuel manifold other than the common rail in a diesel internal combustion engine can be applied.

本発明に係るコモンレールの第１実施例を示す概略図である。It is the schematic which shows 1st Example of the common rail which concerns on this invention. 同じくコモンレールの第２実施例を示す概略図である。It is the schematic which shows 2nd Example of a common rail similarly. 同じくコモンレールの第３実施例を示す概略図である。It is the schematic which shows 3rd Example of a common rail similarly. 同じくコモンレールの第４実施例を示す噴射管接続部の断面図である。It is sectional drawing of the injection pipe connection part which similarly shows 4th Example of a common rail. 同じくコモンレールの第５実施例を示す噴射管接続部の断面図である。It is sectional drawing of the injection pipe connection part which similarly shows 5th Example of a common rail. 同じくコモンレールの第６実施例を示す噴射管接続部の断面図である。It is sectional drawing of the injection pipe connection part which similarly shows 6th Example of a common rail. 同じくコモンレールの第７実施例を示す噴射管接続部の断面図である。It is sectional drawing of the injection pipe connection part which similarly shows 7th Example of a common rail. 同じくコモンレールの第８実施例を示す噴射管接続部の断面図である。It is sectional drawing of the injection pipe connection part which similarly shows 8th Example of a common rail. 同じくコモンレールの第９実施例を示す噴射管接続部の断面図である。It is sectional drawing of the injection pipe connection part which similarly shows 9th Example of a common rail. 同じくコモンレールの第１０実施例を示す噴射管接続部の断面図である。It is sectional drawing of the injection pipe connection part which similarly shows 10th Example of a common rail. 同じくコモンレールの第１１実施例を示す噴射管接続部の断面図である。It is sectional drawing of the injection pipe connection part which similarly shows 11th Example of a common rail. 同じくコモンレールの第１２実施例を示す噴射管接続部の断面図である。It is sectional drawing of the injection pipe connection part which similarly shows 12th Example of a common rail. 同じくコモンレールの第１３実施例を示す噴射管接続部の断面図である。It is sectional drawing of the injection pipe connection part which shows 13th Example of a common rail similarly. 同じくコモンレールの第１４実施例を示す噴射管接続部の断面図で、（Ａ）は縦断正面図、（Ｂ）は（Ａ）のイーイ線上の縦断側面図である。Similarly, it is sectional drawing of the injection pipe connection part which shows 14th Example of a common rail, (A) is a vertical front view, (B) is a vertical side view on the easy line of (A). 同じくコモンレールの第１５実施例を示す噴射管接続部の断面図で、（Ａ）は縦断正面図、（Ｂ）は（Ａ）のローロ線上の縦断側面図である。Similarly, it is sectional drawing of the injection pipe connection part which shows 15th Example of a common rail, (A) is a vertical front view, (B) is a vertical side view on the roll line of (A).

Explanation of symbols

１１Ｕ字形コモンレール
１１−１Ｕ字形本管レール
１１−２噴射管
１１−３キャップ
１２並設形コモンレール
１２−１ストレート形本管レール
１２−２、１３−２、１４−２〜２５−２噴射管
１２−３接続配管
１２−４、１３−３継手
１２−５キャップ
１３環状形コモンレール
１３−１Ｕ字形本管レール
１４〜２５コモンレール
１４−１〜２５−１本管レール

11 U-shaped common rail 11-1 U-shaped main rail 11-2 Injection pipe 11-3 Cap 12 Parallel type common rail 12-1 Straight main rail 12-2, 13-2, 14-2 to 25-2 injection Pipe 12-3 Connection pipe 12-4, 13-3 Fitting 12-5 Cap 13 Annular common rail 13-1 U-shaped main rail 14-25 Common rail 14-1-25-1 Main rail

Claims

A branch hole leading to the flow path is provided in the axial peripheral wall portion of the main rail having a flow path inside the axial center direction, and branch connection is made to the branch hole via a joint member that is integral with or separate from the main rail. In a common rail configured by connecting bodies, a thin-walled thin tube having a t / d (t: thickness, d: outer diameter) of 0.2 to 0.35 is used for the main rail, and the tube is A common rail made of transformation-induced plastic-type strength steel, which is processed into the main rail and then austenite remains by heat treatment.

A branch hole leading to the flow path is provided in the axial peripheral wall portion of the main rail having a flow path inside the axial center direction, and branch connection is made to the branch hole via a joint member that is integral with or separate from the main rail. In a common rail configured by connecting bodies, a thin-walled thin tube having a t / d (t: thickness, d: outer diameter) of 0.2 to 0.35 is used for the main rail, and the tube is A common rail which is made of transformation-induced plastic type strength steel, and after the austenite is generated by heat treatment on the main rail, the main rail is processed.

A long tube is used for the main rail, the plurality of branch holes are provided in a substantially parallel tube portion formed by bending the tube into a U shape, and the branch connection body is provided in the branch hole. The common rail according to claim 1 or 2, which is connected.

The main rail is configured by arranging two short pipes substantially parallel to each other, and the two pipes are branched and connected to a connection pipe so as to be provided on the two pipes. The common rail according to claim 1, wherein the branch connection body is connected to the plurality of branch holes.

The main pipe rail is configured by arranging two pipe bodies formed by bending in a U shape in a substantially annular shape, communicating both ends of the two pipe bodies with a connection pipe, and The common rail according to claim 1 or 2, wherein the branch connection body is connected to the plurality of branch holes provided in two pipe bodies.

After fitting the joint member made of the separate body to the outer peripheral wall portion of the main rail, at least a part of the diameter of the vicinity of the branch hole portion of the main rail is expanded by plastic working so that the joint member is pressed against the main rail. The common rail of Claim 1 or 2 made to fit.

The common rail according to any one of claims 1 to 6, wherein a thin thin tube having an inner diameter of φ3 to φ6 mm and a thickness of 2 to 3 mm is used for the main rail.

The common rail according to any one of claims 1 to 7, wherein brazing or welding is used as connection means of the branch connection body.