JP2010133323A - Common rail - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique improving productivity, in manufacture of a common rail. <P>SOLUTION: The common rail supplying fuel to a plurality of injector pipes is provided. The common rail includes: an injector adapter having an adapter through-hole having a circular recess part for caulking; and a common rail body having a branched flow passage, and a fuel delivery pipe communicating with the branched flow passage and delivering fuel. In the commonrail body, an annular recess part of a recess part formed at a position surrounding the branched flow passage and having an annular shape is formed to an outer peripheral face of the common rail body. The injector adapter is fastened to the commonrail body, by caulking an annular projection part as a projection part formed between the branched flow passage and the annular recess part and having an annular shape, toward the recess part for caulking. In the annular projection part, a pressure receiving seat surface connecting the injector pipe with the flow passage is formed on a branched flow passage side. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a common rail.

  A pressure-accumulation type injection system in which high-pressure fuel is stored in a common rail that is a metal pipe (rail) and fuel is injected by each injector has become widespread. The common rail is generally manufactured by a method including a forging process in order to integrally form a branching cylinder portion that distributes and supplies high-pressure fuel to each injector. On the other hand, the forging process has a low material yield, and every time the injector position changes, the mold used in the forging process must be designed and the production efficiency is low. A technique for achieving this is also proposed (Patent Document 1).

However, since the welding process is a special process that is difficult to inspect and requires quality assurance through process control, there is a problem that the burden of quality control is particularly large.
Japanese Patent Laid-Open No. 9-236064

  The present invention has been made to solve at least a part of the above-described conventional problems, and an object of the present invention is to provide a technique for improving productivity in manufacturing a common rail.

[Application Example 1]
A common rail for supplying fuel to a plurality of injector pipes,
An injector adapter that is a through-hole for penetrating each of the plurality of injector pipes, and in which an adapter through-hole having a circumferential caulking recess is formed;
A common rail main body formed with a branch channel for supplying fuel to an injector pipe fastened through the adapter through-hole, and a fuel distribution channel for distributing fuel in communication with the branch channel;
With
The common rail body further has a shape to which the injector adapter is fitted, and an annular recess that is an annular recess formed at a position surrounding the branch flow path is formed on the outer peripheral surface of the common rail body.
In the state where the injector adapter is fitted in the annular recess, the injector adapter has an annular convex portion which is an annular convex portion formed between the branch flow path and the annular concave portion as the caulking concave portion. It is fastened to the common rail body by caulking toward it,
A common rail in which the pressure-receiving seating surface for connecting the injector pipe and the flow path is formed on the annular flow path side on the annular flow path.

  In the common rail of Application Example 1, since the injector adapter is crimped to the common rail main body, it is not necessary to form a branching cylinder portion in the forging process. Thereby, the forging process can be excluded from the manufacturing process of the common rail. The “crimping recess” has a broad meaning including an engaging portion (for example, the circumferential convex portion 129 in FIG. 13).

  As a result, it is possible to eliminate the decrease in productivity due to the forging process and to use standard products such as round bars, thereby realizing improvement in material yield and production efficiency. In addition, even if the position of the injector is changed, it can be dealt with by simply changing the machining position, so that it is not necessary to newly design and manufacture a forging die, and this can be easily handled.

  The caulking is fastened by caulking an annular convex portion formed between the branch flow path and the annular concave portion toward the caulking concave portion with the injector adapter fitted in the annular concave portion. On the other hand, since the pressure receiving seat surface for connecting to the flow path of the injector pipe is formed on the branch flow path side in the annular convex portion, the caulking fastening is strengthened when the common rail and the injector pipe are joined. Also has the effect of.

[Application Example 2]
A common rail for supplying fuel to a plurality of injector pipes,
An adapter through-hole that is a through-hole for penetrating each of the plurality of injector pipes is formed, and an injector adapter having a circumferential caulking recess formed on the outer periphery; and
A common rail main body formed with a branch channel for supplying fuel to an injector pipe fastened through the adapter through-hole, and a fuel distribution channel for distributing fuel in communication with the branch channel;
With
The common rail body further includes a seating surface for connecting the injector pipe and a flow path, the pressure receiving seating surface formed between the branch flow path and the outer peripheral surface of the common rail body, and the injector In order to fit the adapter, an annular recess that is an annular recess formed at a position surrounding the pressure-receiving seat surface is formed, and
The injector adapter is fastened to the common rail main body by caulking the common rail main body toward a caulking concave portion formed on an outer periphery of the injector adapter in a state where the injector adapter is fitted in the annular concave portion. Common rail.

  The common rail of the application example 2 is an aspect in which the caulking concave portion formed on the adapter through hole side in the application example 1 is provided on the outer peripheral side of the injector adapter. The common rail of the application example 2 has an effect similar to that of the application example 1, and also has a unique effect that the caulking fastening portion can be visually recognized from the outside. The “crimping recess” has a broad meaning including an engaging portion (for example, the circumferential convex portion 129 in FIG. 13).

[Application Example 3]
The common rail of application example 2,
The caulking of the common rail body is performed by forming a caulking groove at a position surrounding the annular recess,
The common rail further includes:
An attachment for coupling the injector pipe to the common rail;
A washer having a cross-sectional shape that fits into the caulking groove, and is fitted to the caulking groove and pressed against the attachment when the injector pipe is coupled to the injector adapter using the attachment. A return restraining washer that restrains the caulking return;
Common rail with.

  The common rail of Application Example 3 has a return restraining washer that is pressed against the attachment when the injector pipe is coupled with the caulking groove and uses the attachment to suppress the return of caulking. With this, the caulking can be firmly maintained.

[Application Example 4]
The common rail of any one of application examples 1 to 3,
The fuel distribution path is a common rail disposed at a position shifted from the centroid position of the common rail body to the opposite side of the annular recess.

  In the common rail of application example 4, the fuel distribution path is arranged at a position shifted from the centroid position of the common rail main body to the opposite side of the annular recess (caulking fastening position). , The rigidity and strength of the common rail body can be efficiently improved at the caulking fastening position).

  The present invention can be realized in various forms other than those described above. For example, the present invention can be realized in the form of a common rail manufacturing method, an internal combustion engine having a common rail, or an automobile including such an internal combustion engine. It is.

  ADVANTAGE OF THE INVENTION According to this invention, the technique which improves productivity can be provided in manufacture of a common rail.

Next, embodiments of the present invention will be described in the following order based on examples.
A. Common rail equipment layout:
B. Common rail configuration:
B-1. Common rail configuration of the comparative example:
B-2. Configuration of the common rail of the first embodiment:
B-3. Configuration of common rail of second embodiment:
C. Variation:

A. Common rail equipment and configuration:
FIG. 1 is an explanatory diagram showing an outline of a common rail fuel injection device 10 of a diesel engine (not shown). The common rail fuel injection device 10 includes a common rail 100, an electronic control device 200, a fuel pump 300, an injector 400, a pressure sensor 500, a relief valve 600, and a fuel tank 700. The common rail type fuel injection device 10 further includes a fuel supply pipe 310, an injector pipe 410, and an attachment 150 that connects these to the common rail 100.

  The fuel flow is as follows. The fuel supplied from the fuel tank 700 is pressurized by the fuel pump 300. The pressurized fuel is supplied to the common rail 100 through the fuel supply pipe 310. The common rail 100 distributes and supplies high-pressure fuel to the four injectors 400 via the four injector pipes 410.

  The electronic control device 200 controls the fuel pressure inside the common rail 100 and the amount and timing of fuel discharge by the injector 400. The control of the fuel pressure is performed by feeding back the pressure measured by the pressure sensor 500 mounted on the common rail 100 and operating the fuel pump 300 so that the fuel pressure inside the common rail 100 approaches the pressure target value. The pressure target value is set by the electronic control device 200 according to the rotational speed and load of the diesel engine.

  Thus, the fuel pressure inside the common rail 100 fluctuates in accordance with the rotational speed and load of the diesel engine, and further pulsates due to fuel discharge by the injector 400. In recent years, a technique in which the fuel pressure inside the common rail 100 is set to an ultrahigh pressure exceeding 200 MPa has been put into practical use.

  The configuration and functions of the common rail used in such an operational environment will be described below by exemplifying each example while comparing with a comparative example for easy understanding.

B. Common rail configuration:
B-1. Common rail configuration of the comparative example:
FIG. 2 is a cross-sectional view showing a part of the common rail 100c of the comparative example. The common rail 100c of the comparative example includes a fuel supply cylinder part 130c for receiving supply of high-pressure fuel from the fuel pump 300, four branch cylinder parts 120c for supplying high-pressure fuel to the four injectors 400, a fuel And a fuel distribution path 111c that distributes the high-pressure fuel supplied from the supply cylinder part 130c to the four branch cylinder parts 120c.

  FIG. 3 is an explanatory view showing a cross section AA of the common rail 100c of the comparative example. The common rail 100c of the comparative example is formed with a branching cylinder portion 120c, a fuel distribution path 111c disposed substantially at the center position (centroid position) of the common rail 100c, and a branch flow path 115pc. In this comparative example, the branching cylinder portion 120c has a male screw 124 for screwing with the attachment 150, and a pressure receiving seat surface 126c for joining the attachment 150 and the flow path. On the other hand, the fuel supply cylinder part 130c has the same configuration as the branch cylinder part 120c. The fuel supply cylinder part 130c and the four branch cylinder parts 120c are formed integrally with the common rail body 110c.

  Such an integral structure is realized by a forging process and machining by machining. The monolithic structure facilitates the design work of the common rail 100c in which fuel that is not allowed to leak is supplied at an ultra-high pressure and has many achievements. Therefore, the common rail 100c is generally manufactured by a manufacturing method including a forging process. Yes. The design work is easy because it is possible to avoid in advance technical problems when the fuel supply cylinder part 130c and the branching cylinder part 120c are provided separately from the common rail body in the outer peripheral direction of the common rail 100c. The technical problem is that it is difficult to ensure required specifications such as sealing performance, rigidity, and strength when the branching cylinder portion 120c and the like are fastened in the outer peripheral direction of the common rail body.

  Under such circumstances, the fact that a forging process is actually required for the production of the common rail constitutes the common general technical knowledge of those skilled in the art at the time of filing. On the other hand, the forging process has a problem that the material yield is low and the mold used in the forging process has to be designed every time the position of the injector is changed, resulting in low production efficiency.

  The inventor of the present application has created a new method of excluding the forging process from the manufacturing process of the common rail after recognizing such technical common sense.

B-2. Configuration of the common rail of the first embodiment:
FIG. 4 is a cross-sectional view showing a part of the common rail 100 in the first embodiment of the present invention. FIG. 4 shows a state in which the common rail body 110 and the adapter 120 and the fuel introduction adapter 130 that are separate from the common rail body 110 are fastened by caulking. The common rail main body 110 is formed with four branch flow paths 115p, a fuel introduction path 113, and a fuel distribution path 111 that distributes the high-pressure fuel introduced from the fuel introduction path 113 to the four branch flow paths 115p. Yes.

  The fuel distribution path 111 of the first embodiment is arranged at a position deviated from the center position (centroid position) of the common rail main body 110, and is therefore the fuel distribution of the comparative example arranged at substantially the center position of the common rail main body 110c. It differs from the path 111c. Specifically, the fuel distribution path 111 is disposed at a position shifted in the common rail body 110 to the side opposite to the side where the adapter 120 or the fuel introduction adapter 130 is mounted. Thereby, the common rail main body 110 can improve the rigidity and intensity | strength of the position where the adapter 120 and the fuel introduction adapter 130 are mounted | worn efficiently.

  The adapter 120 is formed with an adapter through hole 125p for allowing the injector pipe 410 fastened by the attachment 150 to pass therethrough. The adapter through hole 125p is configured to communicate with the branch flow path 115p of the common rail body 110 when the adapter 120 is fastened to the common rail body 110. On the other hand, the fuel introduction adapter 130 is configured so that the fuel introduction adapter through hole 135p communicates with the fuel introduction path 113 by being fastened to the common rail body 110.

  FIG. 5 is an enlarged cross-sectional view of the adapter 120 of the first embodiment. The adapter 120 includes a male screw 124 for fastening to the attachment 150 (FIG. 1), an adapter through hole 125p, a caulking recess 120sg, and an outer peripheral reference surface 120ref. The caulking recess 120sg is a circumferential recess formed in the inner periphery of the adapter through hole 125p in order to fasten the adapter 120 to the common rail body 110. The outer peripheral reference surface 120ref is a reference surface serving as a reference for positioning the mounting position with respect to the common rail main body 110.

  FIG. 6 is a cross-sectional view showing how the common rail body 110 and the adapter 120 are fitted in the first embodiment. FIG. 6 shows the common rail main body 110, the adapter 120 in the fitted state (right side), and the adapter 120 before the fitting (left side).

  In the common rail main body 110, an annular recess 117 into which the adapter 120 and the fuel introduction adapter 130 are fitted is formed around the branch flow path 115 p and the fuel introduction path 113 on the outer peripheral surface of the common rail main body 110. The annular recess 117 and the fuel introduction path 113 into which the fuel introduction adapter 130 is fitted are omitted in the drawing, but have the same configuration. The annular recess 117 can be formed by machining the common rail body 110.

  The reference inner peripheral surface 110ref, which is the inner peripheral surface facing the inner peripheral side of the annular recess 117, is a reference surface that serves as a reference for positioning the mounting position of the adapter 120 and the fuel introduction adapter 130 with respect to the common rail body 110. On the other hand, due to the formation of the annular recess 117, the common rail body 110 is formed with an annular protrusion 118 that is an annular protrusion.

  The outer peripheral reference surface 120ref of the adapter 120 and the reference inner peripheral surface 110ref of the common rail body 110 are preferably fastened by press-fitting or shrink fitting from the viewpoint of fastening rigidity and sealability. Such fastening can be realized by setting a fitting tolerance assuming such a fastening method with respect to the outer peripheral reference surface 120ref and the reference inner peripheral surface 110ref. For example, when the common rail main body 110 is heated by induction heating, the shrink fitting is performed by attaching the adapter 120 and the fuel introduction adapter 130 to the five annular recesses 117 (FIGS. 5 and 6) formed in the same direction. It can be easily realized by dropping it at once and cooling it.

  On the other hand, from the viewpoint of productivity, a fitting tolerance is set so that a minute gap is generated between the outer peripheral reference surface 120ref and the reference inner peripheral surface 110ref so that the insertion can be easily performed without press-fitting or the like. It is preferable.

  FIG. 7 is a cross-sectional view illustrating a fitting state of the common rail 100 and the adapter 120 according to the first embodiment. FIG. 7 shows a state where the adapter 120 is fitted to the common rail body 110. This fitting is realized by fitting the lower end portion where the outer peripheral reference surface 120ref of the adapter 120 is formed into the annular recess 117 formed in the common rail body 110. In this fitting, the annular projection 118 enters the adapter through hole 125p, and the tip of the annular projection 118 reaches a position facing the caulking recess 120sg formed in the adapter through hole 125p. By this fitting, the branch flow path 115p of the common rail 100 and the adapter through hole 125p of the adapter 120 communicate with each other.

  In such a fitting state, when the caulking punch PTL is pressed against the chamfer 117 e formed on the annular convex portion 118, the common rail main body 110 and the adapter 120 can be fastened. Such caulking is realized by the annular convex portion 118 being pushed and expanded by the caulking punch PTL, whereby the annular convex portion 118 is plastically deformed along the shape of the caulking concave portion 120sg.

  FIG. 8 is a cross-sectional view showing a fastening state of the common rail 100 and the adapter 120 according to the first embodiment. In this fastened state, the annular convex portion 118 is plastically deformed by pressing the caulking punch PTL, and is in close contact with the surface of the caulking concave portion 120sg. As a result, the adapter 120 is firmly fastened to the common rail main body 110.

  In this fastened state, the annular convex portion 118 is plastically deformed by caulking in the vicinity of the chamfer 117 e, thereby forming a pressure receiving seat surface 126. The pressure receiving seating surface 126 is a seating surface for joining the flow paths of the injector pipes 410 joined by the attachment 150 (FIG. 1).

  FIG. 9 is a cross-sectional view showing a fastening state of the adapter 120 and the injector pipe 410 according to the first embodiment. The adapter 120 and the injector pipe 410 are fastened by an attachment 150 having a nut 151 and a sleeve 152. When the adapter 120 and the injector pipe 410 are fastened, the branch flow path 115p formed in the common rail body 110 and the injector flow path 415p are connected.

  The branch flow path 115p and the injector flow path 415p are connected to the pressure receiving seat surface 126 formed at the end of the branch flow path 115p by caulking, with the pressure seat surface 416 formed at the end of the injector pipe 410 being connected. It is realized by pressing. Further, this connection is sealed from the outside by plastically deforming at least one of the pressure receiving seat surface 126 and the pressing seat surface 416.

  However, the material of the injector pipe 410 and the common rail body 110 should be selected so that the side of the pressing seat surface 416 formed at the end of the injector pipe 410 is mainly plastically deformed and the side of the common rail body 110 is hardly plastically deformed. Is preferred. This is because even if the injector pipe 410 is replaced, the common rail body 110 can be reused.

  The pressing load of the pressing seat surface 416 against the pressure receiving seat surface 126 is applied from the nut 151 via the sleeve 152. On the other hand, this pressing load works so as to cause elastic deformation in a direction in which the annular convex portion 118 formed with the pressure receiving seat surface 126 is pushed outward. Such a load also acts in the direction of strengthening the caulking fastening between the annular convex portion 118 and the caulking concave portion 120sg.

  As a result, the tightening of the nut 151 performed when the common rail fuel injection device 10 is equipped with the common rail 100 maintains the firm fastening between the common rail main body 110 and the adapter 120.

  Furthermore, in the present embodiment, the branch flow path 115p and the injector flow path 415p of the common rail main body 110 can be directly connected, so that it is possible to add another part without increasing the portion (seal line) that should be considered for sealing against fuel leakage. It has the advantage that the body adapter 120 can be used to connect the flow paths. In other words, in this configuration, the injector pipe 410 and the common rail main body 110 are connected to the common rail main body 110 through the adapter 120 fastened to the common rail main body 110 as a separate body of the common rail main body 110. The formed branch channel 115p and the injector channel 415p of the injector pipe 410 can be directly connected.

B-3. Configuration of common rail of second embodiment:
FIG. 10 is a cross-sectional view illustrating a fitting state of the common rail main body 110a and the adapter 120a before caulking and fastening in the second embodiment. In the adapter 120a of the second embodiment, the caulking recess 120sg formed in the adapter through hole 125p is the caulking recess formed in the outer peripheral surface of the adapter 120a of the second embodiment. It is different in that it is changed to 120 sga.

  On the other hand, the common rail main body 110a of the second embodiment has a common rail surface 119 for mounting the adapter 120a and an annular recess 117a formed on the flat seat surface 119, so that the common rail body of the first embodiment is formed. Different from the main body 110. The annular recess 117a is a recess into which the lower end of the adapter 120a is fitted.

  On the inner peripheral side (the surface on the branch flow path 115p side) of the lower end portion of the adapter 120a and the inner peripheral side (the surface on the branch flow path 115p side) of the annular recess 117a, an inner peripheral reference surface 120refa for positioning, respectively , An outer peripheral reference surface 110refa for positioning is formed. Thereby, relative positioning of the common rail main body 110a and the adapter 120a is possible. The tolerance of these surfaces can be appropriately set according to the fitting method (press fitting, shrink fitting, etc.) as in the first embodiment.

  FIG. 11 is a cross-sectional view showing a state after caulking and fastening of the common rail main body 110a and the adapter 120a in the second embodiment. This caulking is realized by forming a notch 119n with a caulking punch (not shown) and caulking the outer periphery of the common rail main body 110a toward the caulking recess 120sga formed on the outer peripheral surface of the adapter 120a. Such a configuration realizes the advantage that the crimped state can be visually recognized from the outside.

  FIG. 12 is a cross-sectional view showing a fastening state of the adapter 120a and the injector pipe 410 of the second embodiment. The adapter 120a and the injector pipe 410 are fastened by an attachment 150a. The attachment 150a includes a wedge-shaped washer 153 (an example of a “return suppressing washer” in the claims) in addition to the nut 151a and the sleeve 152a.

  In the configuration of the second embodiment, as in the first embodiment, the pressing load on the pressure receiving seat surface 126a by the pressing seat surface 416 of the injector pipe 410 pushes the annular convex portion 118a on which the pressure receiving seat surface 126a is formed outward. It will work to cause elastic deformation in the spreading direction. On the other hand, from the outer periphery of the adapter 120a, the wedge-shaped washer 153 pressed against the nut 151a works to maintain the plastic deformation generated in the caulking.

  Such a load received from the nut 151a also acts in the direction of strengthening the caulking between the annular convex portion 118a and the caulking concave portion 120sga in the second embodiment. As described above, in this configuration, the load is continuously applied so that the wedge-shaped washer 153 is held from the outside of the adapter 120a and the pressing seat surface 416 is held from the inside of the adapter 120a. On the other hand, since the connection between the pressure receiving seat surface 126 and the pressing seat surface 416 is substantially the same as the configuration of the comparative example, the sealing performance can be maintained.

  As a result, the tightening of the nut 151 that is performed when the common rail fuel injection device 10 is equipped with the common rail 100 is the same as in the first embodiment, and the sealing performance between the common rail main body 110 and the adapter 120 is high and strong. The fastening is realized at the same time.

C. Variation:
As mentioned above, although several embodiment of this invention was described, this invention is not limited to such embodiment at all, and implementation in various aspects is possible within the range which does not deviate from the summary. is there. In particular, elements other than the elements described in the independent claims in the constituent elements in each of the embodiments described above can be omitted as appropriate because they are additional elements.

  In the above-described embodiments, not all of the above-described advantages and effects lead to the essential constituent elements of the present invention, and the present invention provides a degree of design freedom for easily realizing each of the above-described advantages and effects. It may be anything that realizes at least one advantage or effect.

  In each of the above-described embodiments, the caulking concave portions 120sg and 120sga are used to perform caulking, but it is not always necessary to use the concave portions, and the circumferential convex portion 129 as shown in FIG. 13 is used. It is also possible to perform caulking. In addition, the “recess for caulking” in the claims has a wide meaning including the circumferential protrusion 129.

Explanatory drawing which shows the outline of the common rail type fuel-injection apparatus 10 of a diesel engine. Sectional drawing which shows a part of common rail 100c of a comparative example. Explanatory drawing which shows the cross section AA of the common rail 100c of a comparative example. Sectional drawing which shows a part of common rail 100 in 1st Example of this invention. The expanded sectional view of the adapter 120 of 1st Example. Sectional drawing which shows the mode of the fitting of the common rail main body 110 and the adapter 120 in 1st Example. Sectional drawing which shows the fitting state of the common rail 100 and adapter 120 of 1st Example. Sectional drawing which shows the fastening state of the common rail 100 and adapter 120 of 1st Example. Sectional drawing which shows the fastening state of the adapter 120 and the injector pipe 410 of 1st Example. Sectional drawing which shows the fitting state before caulking fastening of the common rail main body 110a and adapter 120a in 2nd Example. Sectional drawing which shows the state after caulking fastening of the common rail main body 110a and adapter 120a in 2nd Example. Sectional drawing which shows the fastening state of the adapter 120a and the injector pipe 410 of 2nd Example. Sectional drawing which shows the state after caulking fastening of the common rail main body 110b and adapter 120b in a modification.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Common rail type fuel-injection apparatus 100, 100c ... Common rail 110, 110a, 110b, 110c ... Common rail main body 110refa ... Outer periphery reference surface 110ref ... Reference inner periphery 111, 111c ... Fuel distribution path 113 ... Fuel introduction path 115p, 115pc ... Branch Flow path 117, 117a ... annular recess 118, 118a ... annular projection 119 ... plain seat surface 119n ... notch 120, 120a, 120a ... adapter 120sg, 120sga ... caulking recess 120refa ... inner circumference reference surface 120ref ... outer circumference reference surface 120c ... Branching cylinder part 124 ... Male screw 125p ... Adapter through hole 126, 126a ... Pressure receiving seat surface 129 ... Circular convex part 130 ... Fuel introduction adapter 130c ... Fuel supply cylinder part 135p ... Fuel introduction adapter through hole 150, 150a ... Attachment 151, 151a ... nut 152, 152a ... sleeve 153 ... wedge washer 200 ... electronic control device 300 ... fuel pump 310 ... fuel supply pipe 400 ... injector 410 ... injector pipe 415p ... injector flow path 416 ... pressure seat surface 500 ... pressure Sensor 600 ... Relief valve 700 ... Fuel tank PTL ... Caulking punch

Claims (4)

A common rail for supplying fuel to a plurality of injector pipes,
An injector adapter that is a through-hole for penetrating each of the plurality of injector pipes, and in which an adapter through-hole having a circumferential caulking recess is formed;
A common rail main body formed with a branch channel for supplying fuel to an injector pipe fastened through the adapter through-hole, and a fuel distribution channel for distributing fuel in communication with the branch channel;
With
The common rail body further has a shape to which the injector adapter is fitted, and an annular recess that is an annular recess formed at a position surrounding the branch flow path is formed on the outer peripheral surface of the common rail body.
In the state where the injector adapter is fitted in the annular recess, the injector adapter has an annular convex portion which is an annular convex portion formed between the branch flow path and the annular concave portion as the caulking concave portion. It is fastened to the common rail body by caulking toward it,
A common rail in which the pressure-receiving seating surface for connecting the injector pipe and the flow path is formed on the annular flow path side on the annular flow path. A common rail for supplying fuel to a plurality of injector pipes,
An adapter through-hole that is a through-hole for penetrating each of the plurality of injector pipes is formed, and an injector adapter having a circumferential caulking recess formed on the outer periphery; and
A common rail main body formed with a branch channel for supplying fuel to an injector pipe fastened through the adapter through-hole, and a fuel distribution channel for distributing fuel in communication with the branch channel;
With
The common rail body further includes a seating surface for connecting the injector pipe and a flow path, the pressure receiving seating surface formed between the branch flow path and the outer peripheral surface of the common rail body, and the injector An annular recess that is an annular recess formed in a position that surrounds the pressure-receiving seat surface, and has a shape to which the adapter is fitted;
The injector adapter is fastened to the common rail main body by caulking the common rail main body toward a caulking concave portion formed on an outer periphery of the injector adapter in a state where the injector adapter is fitted in the annular concave portion. Common rail. The common rail according to claim 2,
The caulking of the common rail body is performed by forming a caulking groove at a position surrounding the annular recess,
The common rail further includes:
An attachment for coupling the injector pipe to the common rail;
A washer having a cross-sectional shape that fits into the caulking groove, and is fitted to the caulking groove and pressed against the attachment when the injector pipe is coupled to the injector adapter using the attachment. A return restraining washer that restrains the caulking return;
Common rail with. The common rail according to any one of claims 1 to 3,
The fuel distribution path is a common rail disposed at a position shifted from the centroid position of the common rail body to the opposite side of the annular recess.

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