JP2003343388A - Coupling structure for connecting fuel pipe part to fuel injection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coupling structure for connecting a fuel pipe part to a fuel injection device in which an assembling property and removal strength are enhanced. <P>SOLUTION: The coupling structure has: a first fuel pipe 10 fixed to a fuel injection device 1 side having a first engagement part 10a; a second fuel pipe 20 for leading the fuel in the first fuel pipe 10; a second engagement part 61 engageable with the first engagement part 10a; an arm part 62 extending from the second engagement part 61 to an approximately axial direction; and a connection part 63 connected to the arm part 62. The coupling structure is also provided with a coupling member 60 for connecting the second fuel pipe 20 to the first fuel pipe 20. An axial route Kj for approximately axially moving the second engagement part 61, and a circumferential route Ks for approximately circumferentially moving the second engagement part 61 are provided on the first fuel pipe 10. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a joint structure for connecting a fuel pipe portion to a fuel injection device, and more particularly to a pressure accumulation type fuel injection device for injecting high pressure fuel accumulated in a common rail to an internal combustion engine. The present invention relates to a joint structure for connecting pipes.

[0002]

2. Description of the Related Art As a fuel injection device, for example, in a common rail type fuel injection device as a fuel injection system for a diesel engine, high pressure fuel, which is provided in each cylinder of an internal combustion engine and accumulates pressure in the common rail, is injected into a combustion chamber of the cylinder. It is known that a fuel drain valve for supplying surplus fuel to a fuel tank or the like is attached to a fuel injection valve to be supplied.

As a joint structure of this type of fuel drain pipe for a fuel injection valve, an outlet portion 510 on the fuel injection valve side is provided.
A fuel pipe 520 such as a union pipe for guiding the fuel in the outlet 510 is inserted, and the union pipe 5 is inserted into the outlet 510.
In order to connect 20 to each other, a U-shaped clip 560 is sandwiched from the outside of the union pipe 520, and the outlet portion 5
The union pipe 520 is prevented from coming off from the valve 10 (see FIG. 5). In this clip 560, a flat plate member is formed in a U shape to form an arm portion 562 so that the union pipe 520 can be easily sandwiched from the outside.

[0004]

With the conventional structure, when the U-shaped clip is attached, it is difficult to confirm the fitted portion K on the outlet side, so that the assembly work is easy because of the fitting. There was a problem not. On the contrary, if the fitting force of the clip is suppressed in order to facilitate the workability of assembly, the clip will easily come off from the outlet portion. In some cases, if an excessive load is applied in the pulling direction of the union pipe, the arm part of the clip may open, and as a result, the connection between the outlet part and the union pipe may become insufficient.

The present invention has been made in view of the above circumstances, and therefore an object thereof is a joint structure for connecting a fuel pipe portion to a fuel injection device, which can improve the assemblability and the pull-out strength. To provide.

[0006]

According to claim 1 of the present invention, there is provided a joint structure for connecting a fuel pipe portion to a fuel injection device, which is fixed to the fuel injection device side and has a first locking. A first fuel pipe having a portion, a second fuel pipe for guiding the fuel in the first fuel pipe, a second locking portion engageable with the first locking portion, and a second locking portion A coupling member that connects the second fuel pipe to the first fuel pipe, the arm member extending in a substantially axial direction from the portion, and the connecting portion that connects to the arm portion. An axial path that allows the second locking portion to move in a substantially axial direction and a circumferential path that allows the second locking portion to move in a substantially circumferential direction are provided.

As a result, since the first fuel pipe and the second fuel pipe are connected to each other, when the joint member is assembled, the joint member does not have to be opened unlike the conventional U-shaped joint member, and the arm portion is opened. The second locking portion can be engaged with the first locking portion only by moving the second locking portion in the substantially axial direction and the substantially circumferential direction through the axial path and the circumferential path. That is, the first fuel pipe and the second fuel pipe can be connected by moving the joint member in the substantially axial direction and twisting it in the substantially circumferential direction. Therefore, it is possible to improve the assembling property and the pull-out strength.

According to the second and fourth aspects of the present invention, if a groove, a step, a notch or the like is provided in the first fuel pipe as a path for guiding the second locking portion of the joint member, the shaft can be provided. Directional paths and circumferential paths can be formed.

According to the second aspect, at least one of the axial path and the circumferential path is a groove formed in the first fuel pipe. Thereby, the surface of the first fuel pipe,
For example, since it is easy to form a groove on the outer peripheral surface, it is possible to provide a joint structure for connecting the fuel pipe portion to the fuel injection device at low cost.

According to the third aspect, at least one of the axial path and the circumferential path is a step formed on the first fuel pipe. As a path for guiding the second locking portion of the joint member, one surface along which the second locking portion is provided, that is, a step is sufficient.

According to the fourth aspect, at least one of the axial path and the circumferential path is a notch formed in the first fuel pipe. This makes it easy to sandwich the arm portion extending in the substantially axial direction between the first fuel pipe and the second fuel pipe. For example, even if the arm portion is long, it can be easily sandwiched between the first fuel pipe and the second fuel pipe. As a result, by sandwiching the first fuel pipe and the second fuel pipe between the first fuel pipe and the second fuel pipe, it is difficult to open the arm portion.
It is possible to prevent the engagement between the locking portion and the first locking portion from being disengaged.

According to the fifth aspect of the present invention, the connecting portion has an elastic portion that abuts against the second fuel pipe.

Accordingly, even if, for example, a load in the pull-out direction is applied to the second fuel pipe, the load can be canceled or reduced by the elastic force of the elastic portion that abuts against the second fuel pipe. Can be improved.

According to the sixth aspect of the present invention, the joint member is formed of a rod-shaped body, and the elastic portion has a V-shaped rod-shaped body.

As a result, a V-shape is formed in the connecting portion which is a part of the joint member, so that a predetermined elastic function, for example, an elastic force in the substantially axial direction, is limited to the V-shaped elastic portion. It is possible to add a function to generate. It is possible to increase the rigidity of the joint member as a whole while giving a part of the joint member an elastic function.

According to claim 7 of the present invention, the joint member is formed of a rod-shaped body, and the second locking portion is a curved shape in which the rod-shaped body is curved so that elastic force can be generated substantially in the axial direction. Has become.

As a result, the second locking portion is guided to the first locking portion through the axial path and the circumferential path, and the second locking portion is guided.
It is possible to automatically engage the first locking portion by utilizing the elastic force of the locking portion itself.

Even in the elastic portion according to claim 5, as a reaction force against the acting force generated in the elastic portion,
An elastic force can be applied to the second locking portion.

According to the eighth aspect of the present invention, the first locking portion is provided with the concave portion that can move the second locking portion in the direction in which the elastic force is reduced.

Accordingly, when the joint member has an elastic function of generating elastic force in the substantially axial direction, the second engaging portion and the first engaging portion
The locking part of can be automatically locked. When the fuel pipe is assembled to the fuel injection device in a predetermined positional relationship, the assembling workability can be facilitated.

According to the ninth aspect of the present invention, the plurality of first locking portions are arranged in the circumferential direction of the first fuel pipe.

Thus, when the fuel pipe portion is assembled to the fuel injection device in a predetermined positional relationship, the assembly according to the desired circumferential position becomes easy.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION A joint structure for connecting a fuel pipe portion of the present invention to a fuel injection device will be described with reference to the drawings.

(First Embodiment) FIG. 1 is a structural view showing a structure of a joint structure for connecting a fuel pipe portion of the present embodiment to a fuel injection device, and FIG. 1 (a) is an external view. 1 (b) is a sectional view taken along the line BB in FIG. 1 (a). As shown in FIG. 1, a joint structure for connecting a fuel pipe portion to a fuel injection device includes a fuel injection device 1 (specifically, a connection element 10) and a fuel pipe portion 20 that guides fuel in the connection element 10. , And a clip 60 as a joint member capable of connecting the fuel pipe portion 20 to the connecting element 10.

The connecting element 10 is formed, for example, at the fuel outlet end of the fuel injection valve 1 (see FIG. 5 of the conventional example) as a fuel injection device, and injects fuel into the combustion chamber of the internal combustion engine. Therefore, it is a part of the fuel passage portion for collecting the surplus fuel in the fuel tank (not shown) among the high-pressure fuel supplied to the fuel injection valve 1. Also, this connecting element 10
The fuel tank 20 is connected to the fuel pipe portion 20 that guides the fuel to the fuel tank so as to recover the fuel to the fuel tank, and the opening 20a on the fuel tank side of the fuel pipe portion 20 is set to a predetermined size in view of the positional relationship with the fuel tank. Connecting element 10 in a substantially circumferential direction
It can be assembled to the opening 2 of the fuel pipe 20.
0a may be assembled in a predetermined direction, or any fuel injection device that needs an adjustable function may be used.

The connecting element 10 described in the present embodiment.
That is, the fuel injection device 1 is provided in each cylinder of an internal combustion engine in a so-called common rail fuel injection system having a common rail for accumulating high pressure fuel, and the high pressure fuel accumulated in the common rail is injected and supplied to the combustion chamber of the cylinder. It will be described as a fuel injection valve.

Furthermore, the connecting element 10 as a part of the fuel passage portion may be any member that forms a fuel passage extending from the fuel injection valve 1, and the fuel inside the fuel injection valve 1 may be guided to the outside. It is not limited to a fuel pipe member such as a well-known fuel pipe fixed to the injection valve 1, but may be a part of a member constituting the casing of the fuel injection valve 1. In the present embodiment, the fuel pipe member fixed to the fuel injection valve 1 will be described below. Therefore, in the following description, the fuel pipe section 2
0 is called a second fuel pipe, and the connecting element 10 is called a first fuel pipe.

The second fuel pipe 20 can be hermetically connected to the first fuel pipe 10 when connected to the first fuel pipe 10 by a coupling means such as a clip 60.
An annular groove 20b for accommodating a seal member 30 such as an O-ring is provided. By sandwiching the O-ring 30 between the first fuel pipe 10 and the second fuel pipe 20,
Seal the fuel. The fuel sealing means may be any sealing member or sealing structure as long as it can attach or adjust the circumferential position of the opening 20a of the second fuel pipe 20 to a predetermined position. .
The second fuel pipe 20 may be a well-known union pipe that changes the direction in which the fuel is introduced from the axial direction to the circumferential direction (see FIG. 1). The second fuel pipe 20 includes an axial pipe 21 as an axial fuel passage, a circumferential pipe 22 as a circumferential fuel passage, and a union 23 that hermetically connects the axial pipe 21 and the circumferential pipe 22. Consists of. The axial pipe 21, the circumferential pipe 22, and the union 23 may be separate members integrally assembled and fixed, or may be integrated members.

In order to connect the second fuel pipe 20 to the first fuel pipe 10, the first fuel pipe 10 and the second fuel pipe 2 fitted by the clip 60 are fitted.
The structure of 0 will be described later.

The clip 60 includes a second locking portion 61 which can be engaged with the first locking portion 10a provided on the first fuel pipe 10, and a substantially axial direction from the second locking portion 61. It is configured to include an extending arm portion 62 and a connecting portion 63 that connects to the arm portion 62. The connecting portion 63 connects the arm portion 62a and the arm portion 62b and forms a U-shaped joint portion. At this time, as shown in FIG. 1, the second locking portion 61 may be one that extends in a substantially radial direction from at least one of the arm portion 62a and the arm portion 62b.

Further, when it is desired to rotate the second fuel pipe 20 in a predetermined circumferential direction, both arm portions 62a, 6a.
As shown in FIG. 1, 2b is inserted substantially axially so as to sandwich the second fuel pipe 20, and is twisted substantially circumferentially. As a result, due to the twist of the arms 62a, 62b, that is, the clip 60, the second fuel pipe 2
It is possible for 0 and the clip 60 to engage with each other and move in the substantially circumferential direction. It is desirable that the second fuel pipe 20 be provided with a guide groove 20g for inserting the arm portions 62a and 62b substantially in the axial direction. This allows
The clip 60 can be easily inserted in the axial direction. Further, by twisting the clip 60, the second fuel pipe 20 and the clip 60 can be integrally moved in the substantially circumferential direction.

The connecting portion 63 has an elastic portion E which comes into contact with the second fuel pipe 20 (specifically, the union 23).
The elastic portion E is in contact with the union 23 and can exert an elastic force on the second fuel pipe 20. As a result, due to the elastic force applied to the second fuel pipe 20,
It is possible to connect the second fuel pipe 20 to the first fuel pipe 10. Further, the second fuel pipe 20
Even if a load is applied to the circumferential direction pipe 22, for example, in the axial direction, the influence of the load can be canceled or reduced by the elastic force of the elastic portion E that abuts on the second fuel pipe 20. Therefore, the pull-out strength can be improved.

As the elastic portion E, a clip 60 is formed of a rod-shaped body, and the rod-shaped body is formed in a V shape. Accordingly, the connecting portion 6 that is a part of the clip 60
Since a V-shape is formed in 3, it is possible to impart a predetermined elastic function (specifically, a function for generating an elastic force in the substantially axial direction) to the elastic portion formed in the V-shape. is there. As a result, it is possible to increase the rigidity of the clip 60 as a whole while giving a part of the clip 60 an elastic function. That is, the clip 60 having the second locking portion 62 has a function of generating an elastic force in the substantially axial direction, and the elastic force causes the first locking portion 10 to move.
a, that is, the first fuel pipe 10 can be engaged. Therefore, since it is not necessary to use a method of opening the arm portion and engaging with the first fuel pipe 10 like a conventional clip, the arm portion 62 has an elastic force (specifically,
It is possible to prevent a decrease in rigidity for imparting an elastic force in the direction of opening the arms 62a and 62b (left-right direction in FIG. 1B). Furthermore, since the clip 60 is formed of a rod-shaped member instead of the conventional flat plate member, the rigidity can be easily improved.

Furthermore, due to this V-shape, the connecting portion 63 or the upper end portion of the arm portion 62 can project from the second fuel pipe 20. Therefore, it becomes easy to twist the clip 60 by utilizing the connecting portion 63 having the V shape or the upper end portion of the arm portion 62. The connecting portion 63 protruding from the second fuel pipe 20 and the upper ends of the arm portions 62 form a twist forming portion for twisting the clip 60.

Next, the structure of the second fuel pipe 20 and the first fuel pipe 10 connected by the clip 60, particularly the first fuel pipe 10 having the first engaging portion 10a, will be described below. The first fuel pipe 10 is the second
Axial path Kj capable of moving the locking portion 61 of the substantially axial direction
And a circumferential path Ks capable of moving the second locking portion 61 in a substantially circumferential direction. Thus, when the clip 60 is assembled to connect the first fuel pipe 10 and the second fuel pipe 20, the arm portion 6 is used like a conventional clip.
2 without opening the second locking portion 61, the axial path K
It is possible to engage with the first locking portion 10a simply by moving it in the substantially axial direction and the substantially circumferential direction through j and the circumferential path Ks. Specifically, the axial route Kj and the circumferential route Ks
Is a notch formed in the first fuel pipe 10.
As shown in FIG. 1, this notch has a substantially L-shaped notch, and can move the second locking portion 61 in the arrow direction L of FIG. 1, that is, in the substantially axial direction and the substantially circumferential direction. It is possible.
As a result, the first fuel pipe 10 and the second fuel pipe 20 can be easily connected by moving the clip 60 in the substantially axial direction and twisting it in the substantially circumferential direction.

The first engaging portion 10a constitutes at least a part of the circumferential path Ks of the axial path Kj and the circumferential path Ks.

In the joint structure between the clip 60 and the first fuel pipe 10 described above, the conventional arm portion is opened to make the first structure.
As compared with the joint structure for connecting the fuel pipe 10 and the second fuel pipe 20 of FIG.

Further, in the present embodiment, as shown in FIG. 1, since the axial path Kj and the circumferential path Ks are formed by the notches, the size of the second locking portion 10a extending in the substantially radial direction is set. Regardless, it becomes easy to sandwich the arm portion 62 of the clip 60 between the first fuel pipe 10 and the second fuel pipe 20. Thereby, even if the arm portion 62 is long, for example, it can be easily sandwiched between the first fuel pipe 10 and the second fuel pipe 20. As a result, the first fuel pipe 10 and the second fuel pipe 20
The arm portion 62 can be prevented from being opened easily by sandwiching the arm portion 62 between the arm portion 62 and the arm portion, and thus the arm portion 62 can be prevented from opening and the second locking portion 61 and the first locking portion 10a being disengaged. .

Further, in this embodiment, as shown in FIG. 1, an axial path (hereinafter referred to as a locking axial path) Kjs is provided at the end of the circumferential path Ks. The axial path Kj, the circumferential path Ks, and the locking axial path Kjs
Forms a substantially J-shaped notch. It should be noted that the locking axial path Kjs may be such that the second locking portion 61 can slightly move in the axial direction. As a result, the locking axial path js can automatically lock the second locking portion 61. That is, when the elastic portion E of the clip 60 is used to engage the second locking portion 61 with the notch of the circumferential path Ks with a predetermined elastic force in the axial direction, the second stopper portion 61 is moved along the notch.
The second locking portion 61 is automatically fitted into the locking axial path js in which the elastic force is reduced only by moving the locking portion 61 in the substantially circumferential direction.

The locking axial path Kjs may be a recess formed in a part of the circumferential path Ks, that is, the first locking portion 61. This recess Kjs has a clip 60.
It is desirable that the elastic force, that is, the reaction force acting on the second locking portion 61, be movable in a direction in which the reaction force is reduced. As a result, the first locking portion 10a and the second locking portion 61 can be automatically locked. Therefore, when the second fuel pipe 20 is assembled to the first fuel pipe 10, that is, the fuel pipe 20 to the connecting element 10 of the fuel injection device 1 in a predetermined positional relationship, the assembling workability can be facilitated.

Furthermore, the clip 60 of the present embodiment.
Has one second locking portion 61. Therefore, it becomes easy to arrange a plurality of first locking portions 10a in the circumferential direction of the first fuel pipe 10. As a result, when the fuel pipe portion 20 is assembled to the fuel injection device 1 in a predetermined positional relationship, the assembly according to the desired circumferential position becomes easy.

The number of the second locking portions 61 provided on the clip 60 is not limited to one, but two or more locking portions can be assembled according to the desired circumferential position.

A method of assembling the above-mentioned joint structure will be described below. The second fuel pipe 20 is inserted into the first fuel pipe 10 while sandwiching the seal member 30 between the second fuel pipe 20 and the first fuel pipe 10. Next, the clip 60 is inserted into the guide groove 20g of the second fuel pipe 20. The clip 60 is inserted in the substantially axial direction along the guide groove 20a, and the second locking portion 61 of the clip 60 is guided to the axial path Kj of the second fuel pipe 10. Further, when the elastic portion E is moved in the axial direction along the axial path Kj, the elastic portion E moves to the second position.
Abutting on the fuel pipe 20. At this time, the clip 60
Is only inserted in the substantially axial direction, and the second locking portion 61 has not reached the axial position at which it can be engaged with the notch of the circumferential path Ks. Further, while applying a load to the clip 60, that is, the elastic portion E, the clip 60 is inserted to an axial position where the second locking portion 61 can be inserted into the notch of the circumferential path Ks. After that, when the clip 60 is twisted using the twist forming portion of the clip 60, the second locking portion 61
Moves substantially in the axial direction along the notch of the circumferential path Ks. When the second locking portion 61 is moved to the end in the circumferential path Ks direction and the load on the elastic portion E is stopped, the second locking portion 61 causes the locking axial path Kjs, that is, the locking axial path Kjs. The first locking portion 10a is automatically locked by utilizing the elastic force.

It should be noted that the second engaging portion 61 is connected to the circumferential path Ks.
As long as it is inserted in the middle of or at the end, the elastic force generated by the elastic portion E causes the second locking portion 61 and the circumferential path Ks, that is, the second locking portion 61 and the first locking portion 10a.
Since the and are engaged, the second fuel pipe 20 can be connected to the first fuel pipe 10. Even if a load is applied in the direction of pulling out the second fuel pipe 20, the circumferential path Ks and the second
The engagement of the locking portion 61 can prevent the release of the connection between the second fuel pipe 20 and the first fuel pipe 10.

The clip 60 of this embodiment is formed of a rod-shaped body, and has a second locking portion 61 which can be engaged with the first locking portion 10a of the first fuel pipe 10 and an arm portion 62.
a, 62b and the arm portions 62a, 62b are connected to each other, and the second
Connecting portion 6 having an elastic portion E that abuts the fuel pipe 20 of
3, when the clip 60 is inserted and assembled, the axial movement of the second locking portion 61 in the vertical direction (see FIG. 1B) and the twisting of the second locking portion 61 in the circumferential direction, so-called It is a joint means that moves in the circumferential direction (see FIG. 1A).

As a result, the clip 60 utilizes the elastic force of the elastic portion E to move the second locking portion 61 to the first locking portion 1.
0a can be engaged. Moreover, the axial movement of the second locking portion 61 moves not only downward but also vertically, which is suitable for an automatic locking structure.

In the present embodiment, the axial path Kj and the circumferential path Ks are notches formed in the first fuel pipe 10, but the second locking portion 61 is substantially axial and circumferential. Any route may be used as long as it is a route leading in the direction, and may be a groove, a step or the like.

(Second Embodiment) Another embodiment to which the present invention is applied will be described below. In the following embodiments, the same or equivalent components as those in the first embodiment are designated by the same reference numerals and the description thereof will not be repeated.

In the second embodiment, as shown in FIG.
The elastic portion E described in the first embodiment is provided in the second locking portion 61 instead of the connecting portion 63. FIG. 2 is a configuration diagram showing a configuration of a joint structure for connecting the fuel pipe portion of the present embodiment to the fuel injection device, and FIG.
FIG. 2B is a sectional view taken along the line BB in FIG. As shown in FIGS. 2A and 2B, the second locking portion 61 has a shape capable of generating elastic force by contacting at least the circumferential path Ks. The shape is shown in FIG.
As shown in (b), the rod-shaped body is curved so that elastic force can be generated substantially in the axial direction. The elastic portion E, that is, the second locking portion 61 is larger than the width of the cutout of the circumferential path Ks. Accordingly, when the second locking portion 61 is inserted into the circumferential path Ks, the second locking portion 61 can be engaged with the circumferential path Ks by a predetermined elastic force (specifically, an axial elastic force). .

In the method of assembling the joint structure described above, the parts different from those of the first embodiment will be described below. The clip 60 is inserted into the guide groove 20g of the second fuel pipe 20. The clip 60 is inserted in the substantially axial direction along the guide groove 20a, and the second locking portion 61 of the clip 60 is guided to the axial path Kj of the second fuel pipe 10 to the lower end of the axial path Kj. insert. At this time, clip 6
0 is a state in which it is only inserted in the substantially axial direction, and the second locking portion 61 is not elastically deformed and no elastic force is generated.
Furthermore, by applying a load to the clip 60 (specifically, the connecting portion 63), the width of the second locking portion 61 is set to the circumferential path K.
It is elastically deformed to a width of s or less and contracted. After that, when the clip 60 is twisted using the twist forming portion of the clip 60, the second locking portion 61 moves in the substantially axial direction along the notch of the circumferential path Ks.

With this structure, as in the first embodiment, the assembling property and the pull-out strength can be improved.

(Third Embodiment) In the third embodiment,
As shown in FIG. 3, the clip 60 is inserted along the outer peripheries of the first fuel pipe 10 and the second fuel pipe 20. FIG. 3 is a configuration diagram showing a configuration of a joint structure for connecting the fuel pipe portion of the embodiment to a fuel injection device,
3 (a) is an external view, and FIG. 3 (b) is B- in FIG. 3 (a).
It is the sectional view seen from B.

As shown in FIG. 3, the circumferential path Ks is a step formed in the first fuel pipe 10. If this step is an annular step formed at the upper end of the first fuel pipe 10 or a plurality of step portions arranged in an annular shape,
Either is fine. It is possible to move the second locking portion 61 in a substantially circumferential direction along a surface that forms a step (a surface that is substantially orthogonal to the paper surface of FIG. 3A) (see FIG. 3A). The axial path Kj is a groove formed between the step portions in the circumferential direction of the first fuel pipe 10.

In this embodiment, the first locking portion 10
a is formed in the first fuel pipe 10 and is formed in a flange shape arranged in plural in the circumferential direction. The lower end surface of the first locking portion 10a forms a step in the circumferential path Ks. The groove formed between the first locking portions 10a forms the axial path Kj.

Furthermore, on the lower end surface of the first locking portion 10a, the locking axial path Kj described in the first embodiment is used.
A concave portion corresponding to s is formed.

The load applied to the connecting portion 63, that is, the elastic portion E is such that the second engaging portion 61 can be moved in the substantially circumferential direction along the lower end surface of the first engaging portion 10a.

As a result, similarly to the first embodiment, without opening the arm portions 62a and 62b of the clip 60,
The second locking portion 61 can be engaged with the first locking portion 10a. Further, the second locking portion 61 and the first locking portion 10a can be automatically locked by the locking axial path Kjs provided on the circumferential path Ks.

Furthermore, in the present embodiment, it is desirable that the second locking portion 61 has a recess 61a inside. As a result, as shown in FIG. 3, the flange-shaped first
Since the locking portion 10a is sandwiched, it is possible to prevent the second locking portion 61 and the first locking portion 10a from being disengaged from each other.

In the method of assembling the joint structure described above, when the clip 60 is inserted and guided to the circumferential path Ks,
As the load applied to the connecting portion 63, the upper end surface 6 of the recess 61a is
It suffices to apply a load such that 1b contacts the first locking portion 10a. Therefore, it is not necessary to manage the load applied to the connecting portion 63 within a predetermined load range, and the work of assembling the clip 60 becomes easy.

(Fourth Embodiment) In the fourth embodiment,
As shown in FIG. 4, as the locking axial path Kjs, instead of the recess formed in the lower end surface of the first locking portion 10a described in the third embodiment, the first locking portion 10a is provided. The recess 11a is provided in the groove 11 provided below.

As shown in FIG. 4, the circumferential path Ks is defined by a step forming the lower end surface of the first locking portion 10a and a step forming the groove 11. That is, the circumferential path Ks is a groove that forms the first locking portion 10a.
The groove 11 has an axial path Kj that allows the second locking portion 61 to move in the axial direction.

In this embodiment, one arm portion 6
2 has two second locking portions 61. Arm 62a
The second engaging portions 61 provided on the first and second engaging portions 61 engage with the first engaging portion 10a and the groove 11, respectively. The same applies to the second locking portion 61 provided on the arm portion 62b. Second locking portion 61
By engaging with the concave portion 11a, automatic locking is possible.

Even if the circumferential path Ks is a groove formed in the first fuel pipe 10 as in the present embodiment, the third path Ks
Similarly to the above embodiment, the arm portion 62a of the clip 60,
The second locking portion 61 can be engaged with the first locking portion 10a without opening the 62b.

In the embodiment of the present invention described above,
The first fuel pipe 10, that is, the connecting element of the fuel injection device 1, has a joint structure in which the second locking portion 61 is engaged with the first locking portion 10a without opening the arms 62a and 62b of the clip 60. 10 includes an axial path Kj capable of moving the second locking portion 61 in the substantially axial direction and a circumferential path Ks capable of moving the second locking portion 61 in the substantially circumferential direction, It can be applied to any joint structure.

At least one of the axial path Kj and the circumferential path Ks may be a groove, a step, or a notch formed in the first fuel pipe 10. If it ’s a groove,
It can be easily formed on the surface of the first fuel pipe, for example, the outer peripheral surface. Therefore, it is possible to provide the joint structure for connecting the fuel pipe portion to the fuel injection device 1 at low cost. Further, as a path for guiding the second locking portion 61, one surface along which the second locking portion 61 is provided, that is, a step is sufficient. Furthermore, if it is a notch, it becomes easy to sandwich the arm portion 62 between the first fuel pipe 10 and the second fuel pipe 20.

[Brief description of drawings]

1A and 1B are configuration diagrams showing a configuration of a joint structure for connecting a fuel pipe unit to a fuel injection device according to a first embodiment of the present invention, FIG. 1A being an external view and FIG. ) Is Figure 1
It is sectional drawing seen from BB in (a).

2A and 2B are configuration diagrams showing a configuration of a joint structure for connecting a fuel pipe portion of a second embodiment to a fuel injection device, wherein FIG. 2A is an external view and FIG. It is sectional drawing seen from BB in 2 (a).

3A and 3B are configuration diagrams showing a configuration of a joint structure for connecting a fuel pipe portion of a third embodiment to a fuel injection device, wherein FIG. 3A is an external view and FIG. It is sectional drawing seen from BB in 3 (a).

4A and 4B are configuration diagrams showing a configuration of a joint structure for connecting a fuel pipe portion of a fourth embodiment to a fuel injection device, wherein FIG. 4A is an external view and FIG. It is sectional drawing seen from BB in 4 (a).

FIG. 5 (a) is an explanatory view illustrating a structure for mounting a conventional fuel drain pipe for a fuel injection valve, and FIG.
Is a partial sectional view of the fuel injection valve showing the structure, FIG.
5B is a perspective view of a joint member for connecting the fuel injection pipe to the fuel injection valve in the fuel injection valve of FIG. 5A, and FIG. 5C is the fuel injection valve of FIG. 5A. 3 is a cross-sectional view showing a joint structure for connecting a fuel injection pipe to a fuel injection valve.

[Explanation of symbols]

1 Fuel injection valve (fuel injection device) 10 Connection element (first fuel pipe) 10a First locking portion 20 Fuel pipe section (second fuel pipe) 20a opening 20g guide groove 30 Seal member (O-ring) 60 clip (joint member) 61 First locking portion 61a recess 62 (62a, 62b) arm part 63 Connection E Elastic part Kj axial direction path Ks Circumferential route Kjs locking axial path (recess)

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 3G066 AA07 BA56 CB05 CD04                 3J037 AA01 BA01 BA04 BB01 BB03                       CA04                 3J039 AA03 AB05 BB01 JA16 JA18                 3J106 AA01 AB01 BA01 BB02 BC04                       BD01 BE22 CA07 EB05 EC01                       EC07 ED33 EE02 EF04

Claims (9)

[Claims] 1. A joint structure for connecting a fuel pipe part to a fuel injection device, comprising: a first fuel pipe fixed to the fuel injection device side and having a first locking part; A second fuel pipe for guiding the fuel in the fuel pipe, a second engaging portion engageable with the first engaging portion, and the second engaging portion.
A joint member for connecting the second fuel pipe to the first fuel pipe, the arm member extending substantially axially from the locking portion of the second fuel pipe, and a connecting portion connecting to the arm portion. The first fuel pipe is provided with an axial path capable of moving the second locking portion in a substantially axial direction and a circumferential path capable of moving the second locking portion in a substantially circumferential direction. A joint structure for connecting a fuel pipe portion to a fuel injection device, which is characterized in that 2. The fuel injection device for a fuel pipe portion according to claim 1, wherein at least one of the axial path and the circumferential path is a groove formed in the first fuel pipe. Joint structure for connecting to. 3. The fuel injection device for a fuel pipe portion according to claim 1, wherein at least one of the axial path and the circumferential path is a step formed in the first fuel pipe. Joint structure for connecting to. 4. The fuel injection unit for a fuel pipe according to claim 1, wherein at least one of the axial path and the circumferential path is a notch formed in the first fuel pipe. Joint structure for connecting to equipment. 5. The fuel injection device for a fuel pipe portion according to claim 2, wherein the connecting portion has an elastic portion that abuts against the second fuel pipe. Joint structure for connecting to. 6. The fuel injection device according to claim 5, wherein the joint member is formed of a rod-shaped body, and the elastic portion has a V-shaped rod-shaped body. Joint structure for connecting. 7. The joint member is formed of a rod-shaped body, and the second locking portion has a curved shape in which the rod-shaped body is curved so that elastic force can be generated substantially in the axial direction. A joint structure for connecting the fuel pipe section according to any one of claims 2 to 4 to a fuel injection device. 8. The second locking portion according to claim 2, wherein the first locking portion is provided with a concave portion capable of moving the second locking portion in a direction in which elastic force is reduced. A joint structure for connecting the fuel pipe section according to any one of claims 1 to 3 to a fuel injection device. 9. The fuel according to claim 1, wherein a plurality of the first locking portions are arranged in a circumferential direction of the first fuel pipe. A joint structure for connecting a pipe portion to a fuel injection device.