JP2003021026A - Fuel injection device and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel injection device and a manufacturing method thereof capable of being formed into a desired shape for respective models of an engine, easily changing the design, easily processing, and capable of exhibiting enhanced strength. SOLUTION: A housing 10 is divided into a fuel supply member 11, a main body member 12, a fuel recovery member 13 and a connection member 14. Therefore, the shape of the fuel supply member 11, the main body member 12, the fuel recovery member 13 and the connection member 14 can be individually selected in accordance with a shape of the engine and a periphery member to be mounted. Accordingly, the design of an injector 1 can be easily changed. By dividing the housing 10 into the fuel supply member 11, the main body member 12, the fuel recovery member 13 and the connection member 14, the respective members can be individually formed, a whole length of a narrow hole forming a passage of the respective members can be shortened, and the processing can be performed easily. The respective members are welded by an electron beam or diffusely joined, and the strength similar to the integral forming is secured.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an internal combustion engine (hereinafter,
An internal combustion engine is called an "engine." ) And a method for manufacturing the same, and particularly to a fuel injection apparatus used in a common rail fuel injection system and a method for manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, a common rail type fuel injection system has been used as a fuel injection system for diesel engines. In the common rail fuel injection system, the fuel pressurized by the high-pressure fuel pump is stored in the common rail in an accumulated state, and the high-pressure fuel stored in the common rail is distributed to the fuel injection device installed in each cylinder of the engine. .

High-pressure fuel is supplied from a common rail to a fuel injection device used in a common rail fuel injection system. Therefore, the fuel injection device is required to have a high pressure resistance performance, and the conventional fuel injection device has a fuel supply portion to which high-pressure fuel is supplied from the common rail, a main body portion connected to the fuel injection nozzle, and a surplus in the main body portion. The fuel recovery unit for discharging the exhausted fuel is formed integrally.

[0004]

However, when the fuel supply section, the main body section and the fuel recovery section of the fuel injection device are integrally formed, there are the following problems. First, since the method of mounting on the engine and the shape of the periphery of the fuel injection device mounted on the engine differ depending on the model of the engine, the shape of the fuel injection device becomes complicated and diversified. Second, since the shape of the fuel injection device is complicated and diversified,
It is difficult to process the material into a desired shape. Thirdly, if the fuel injection device is integrally formed, it is necessary to form a long hole having a long length that serves as a fuel passage, which complicates the manufacturing process and increases the number of stages.

On the other hand, in order to solve the above-mentioned problems, it is considered that a part of the fuel injection device is formed as a separate body and is connected by screwing or the like. However, the size of the fuel injection device is increased in order to secure the screw tightening portion. In addition, a shape portion for securing the strength of the joint portion and tightening with a screw is required, and a model in which a separate structure can be adopted is limited.

Therefore, an object of the present invention is to provide a fuel injection device which can be molded into a desired shape for each engine model, is easy in design change and processing, and has high strength, and a manufacturing method thereof.

[0007]

According to the method of manufacturing a fuel injection device according to claim 1 or the fuel injection device according to claim 7 of the present invention, a fuel supply member constituting a fuel supply portion and a main body portion are constituted. The main body member and the fuel recovery member forming the fuel recovery unit are joined to the connection member forming the connection unit. By configuring the fuel injection device with the fuel supply member, the main body member, the fuel recovery member, and the connecting member, the fuel injection path is formed in the fuel supply passage formed in the fuel supply member, the fuel passage formed in the main body member, and the fuel recovery member. The fuel discharge passage and the connecting passage formed in the connecting member may be narrow holes each having a short overall length. Further, by dividing the fuel injection device into a plurality of members, the shape of each member is simplified. Therefore, the fuel injection device can be easily processed.

Further, since the fuel injection device can be constructed by combining the fuel supply member, the main body member, the fuel recovery member, and the connecting member as necessary, the fuel can be adjusted according to the shape of the engine and the shape around the mounting portion. The shape of the injection device can be easily changed. Therefore, a fuel injection device having a desired shape can be molded for each engine model, and the design of the fuel injection device can be easily changed.

According to the second aspect of the fuel injection device of the present invention, the shape of the fuel supply member, the main body member, the fuel recovery member, and the connecting member is selected for each model, and the selected members are joined together. . Therefore, the shapes of the fuel supply member, the main body member, the fuel recovery member or the connecting member can be selected according to the engine model. Therefore, a fuel injection device having a desired shape can be formed for each engine model.

According to the third aspect of the fuel injection device of the present invention, any one of the fuel supply member, the main body member, the fuel recovery member and the connecting member is integrally formed with the other member.
That is, the fuel injection device is divided into two or more members that form the fuel supply unit, the main body unit, the fuel recovery unit, or the connection unit. Therefore, a fuel injection device having a desired shape can be molded for each engine model, and the number of parts can be reduced.

According to the fourth aspect of the present invention, the joint between the fuel supply member, the main body member or the fuel recovery member and the connecting member is perpendicular to the axis of the fuel supply passage, the fuel passage or the fuel discharge passage. Is doing. Since the fuel flowing through the fuel supply passage, the fuel passage, or the fuel discharge passage has a high pressure, a force in the radial direction is applied to each passage due to the pressure of the fuel. By forming the joint portion perpendicular to the axis of the passage, no force is applied in the direction in which the members are separated from each other by the pressure of the fuel. Therefore, the strength of the fuel injection device with respect to the fuel pressure can be increased.

According to a fifth aspect of the present invention, there is provided a fuel injection device, or a eighth aspect of the fuel injection device manufacturing method, wherein the fuel supply member, the main body member, the fuel recovery member and the connecting member are electron beams. Joined by welding or diffusion bonding. Therefore, it is possible to secure high strength of the joint portion. Moreover, since it is not necessary to tighten the screws, the strength can be increased without increasing the size of the body.

According to the method of manufacturing a fuel injection device of the seventh aspect of the present invention, the fuel supply member, the main body member, the fuel recovery member and the connecting member are individually processed. Therefore, the shape of each member can be easily processed into a desired shape, and the fuel supply passage, the fuel passage, the fuel discharge passage, and the connection passage can be formed as narrow holes having a short overall length. When the fuel supply member, the main body member, and the fuel recovery member are joined to the connecting member, the pin member is fitted into one of the passages formed in the members joined to each other. As a result, each member is temporarily joined, and each member can be positioned. The temporarily joined members are main-joined by, for example, electron beam welding, and after the main-joining, the pin member remaining in the passage is removed. Therefore, the fuel supply member, the main body member, the fuel recovery member, and the connection member can be joined with high accuracy.

According to the method for manufacturing a fuel injection device of the tenth aspect of the present invention, the fuel supply member, the main body member, the fuel recovery member, and the connecting member are formed by forming. Therefore, each member can be easily formed and processing is easy. According to the eleventh aspect of the method of manufacturing the fuel injection device of the present invention, the fuel supply passage, the fuel passage, the fuel discharge passage, and the connection passage are formed by forming a blank. Therefore, each passage can be easily formed, and processing is easy.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment showing an embodiment of the present invention will be described below with reference to the drawings. FIG. 2 shows an injector as a fuel injection device according to an embodiment of the present invention. The injector 1 is inserted and mounted in a cylinder head of an internal combustion engine (not shown), and is configured to directly inject fuel into each cylinder of the internal combustion engine.

The injector 1 is applied to a common rail type fuel injection system. The injector 1 mainly includes a housing 10, a nozzle unit 20, and an electromagnetic drive unit 30. The nozzle portion 20 is provided on the side of the housing 10 opposite to the electromagnetic drive portion 30. The nozzle portion 20 has a nozzle body 21, and a nozzle hole 22 is formed near the tip of the nozzle body 21. Further, a valve needle 23 as a movable member is housed inside the nozzle body 21 so as to be capable of reciprocating in the axial direction. An abutting portion 23a is formed on the valve needle 23, and a valve seat portion 21a formed on the inner peripheral side of the nozzle body 21.
Can be contacted with. When the contact portion 23a is seated on the valve seat portion 21a or the valve seat portion 21a is separated from the contact portion 23a, fuel injection from the injection hole 22 is interrupted.

A control piston 41, which is a movable member that abuts the valve needle 23, is housed inside the housing 10. A pressure control chamber 42 is formed on the inner peripheral side of the housing 10 on the side opposite to the valve needle of the control piston 41. In the pressure control chamber 42, the fuel inlet 43
The high-pressure fuel supplied from is stored. Pressure control room 4
The high-pressure fuel stored in 2 urges the control piston 41 downward in FIG. When the control piston 41 is biased by the fuel in the pressure control chamber 42, the control piston 41
The valve needle 23 that comes into contact with is urged in the injection hole closing direction. That is, the abutting portion 23a of the valve needle 23 is biased in a direction to be seated on the valve seat portion 21a of the nozzle body 21.

The electromagnetic drive unit 30 is installed on the opposite side of the housing 10 from the nozzle unit 20. Electromagnetic drive unit 30
Has an electromagnetic valve (not shown) that discharges the fuel stored in the pressure control chamber 42. When the solenoid valve is opened and the fuel in the pressure control chamber 42 is discharged, the pressure inside the pressure control chamber 42 decreases, and the force that urges the valve needle 23 in the injection hole closing direction decreases. Then, the valve needle 23 is urged in the injection hole opening direction by the fuel pressure in the vicinity of the valve seat portion 21a rather than the force by which the fuel pressure in the pressure control chamber 42 urges the valve needle 23 in the injection hole closing direction. When the applied force increases, the valve needle 23 lifts upward in FIG. When the valve needle 23 is lifted, the contact portion 23
a is separated from the valve seat portion 21a, and fuel is injected from the injection hole 22.

On the other hand, the solenoid valve is closed, and the pressure control chamber 42
When the discharge of fuel from is stopped, the pressure inside the pressure control chamber 42 increases, and the force that urges the valve needle 23 in the injection hole closing direction increases. Therefore, the valve needle 2
3 moves downward in FIG. 2, and the abutting portion 23a becomes the valve seat portion 21a.
Sit down. When the contact portion 23a is seated on the valve seat portion 21a, fuel injection from the injection hole 22 is stopped.

The fuel inlet 43 is supplied with high-pressure fuel stored in a common rail (not shown) in a pressure-accumulated state. The high-pressure fuel supplied from the common rail is supplied to each part of the injector 1 via the fuel supply path 111. Part of the fuel supplied from the fuel supply path 111 is supplied to the pressure control chamber 42, and the other part is supplied to the nozzle unit 20.
Is supplied to.

Next, the housing 10 of the injector 1 will be described in detail. As shown in FIGS. 1 and 2, the housing 10 is composed of a fuel supply member 11, a main body member 12, a fuel recovery member 13, and a connection member 14. The fuel supply member 11 constitutes a fuel supply section of the injector 1. The fuel supply unit is connected to a common rail (not shown), and high-pressure fuel is supplied from the common rail.
The end of the fuel supply member 11 is a fuel inlet 43 connected to a pipe from a common rail (not shown). The fuel supply member 11 has a fuel supply path 111 inside.
A part of the fuel supply path 111 serves as a filter housing portion 112 having an increased inner diameter, and a filter member 113 is housed in the filter housing portion 112.

The main body member 12 constitutes the main body of the injector 1. The main body is fixed to a cylinder head of an engine (not shown). Therefore, the main body member 12 is molded according to the shape of the mounting portion formed on the cylinder head. The main body member 12 has a nozzle portion 2 at one end.
0 is connected, and the connecting member 14 is joined to the other end. A fuel passage 121, a housing hole 122, and a fuel passage 123 are formed inside the main body member 12. One of the fuel passages 121 is the fuel supply passage 11 of the fuel supply member 11.
Nozzle body 21 of the nozzle part 20 connected to the other one
It is connected to the fuel sump 212 via the fuel passage 211 formed in. High-pressure fuel is supplied to the fuel passage 121 from the common rail via the fuel supply passage 111. The control piston 41 is housed in the housing hole 122 so as to be capable of reciprocating. One end of the fuel passage 123 is connected to the nozzle portion 20, and excess fuel in the nozzle portion 20 is discharged to the fuel recovery portion.

The fuel recovery member 13 constitutes a fuel recovery section of the injector 1. The fuel recovery unit is connected to a fuel tank (not shown). The fuel recovery member 13 has a fuel discharge passage 131 formed therein, and excess fuel is returned to the fuel tank via the fuel discharge passage 131.

The connecting member 14 constitutes a connecting portion of the injector 1. The connection member 14 connects the main body member 12, the fuel supply member 11, and the fuel recovery member 13. The connection member 14 includes a housing hole 141 and a connection passage 1 inside.
42, a fuel pipe 143 and a connection passage 144 are formed. An end of the control piston 41 on the side opposite to the valve needle 23 is housed in the housing hole 141, and a pressure control chamber 42 is formed between the end of the control piston 41 and the valve seat member 31 of the solenoid valve. . The connection passage 142 includes the fuel supply passage 111 formed in the fuel supply member 11 and the main body member 12.
To the fuel passage 121 formed in. The fuel pipe 143 is branched from the connection passage 142 and branches from the pressure control chamber 42.
Connected to. The connection passage 144 has the fuel recovery member 1
3, the fuel discharge passage 131 formed in the main body member 12, the fuel passage 123 formed in the main body member 12, and the fuel passage 145 through which surplus fuel is discharged by the solenoid valve are connected.

As shown in FIG. 3, the fuel supply member 11, the main body member 12, the fuel recovery member 13 and the connecting member 14 are
Each member is designed in various shapes according to the model of the engine to be mounted and the shape around the mounting part. The fuel supply member 11, the main body member 12, the fuel recovery member 13, and the connection member 14 are each molded into a predetermined shape, and the molded members are joined together to form the housing 1 of the injector 1.
0 is formed.

As shown in FIG. 2, the joint 51 between the fuel supply member 11 and the connecting member 14 is formed perpendicular to the axis of the fuel supply passage 111. The joint 52 between the body member 12 and the connecting member 14 is formed perpendicular to the axis of the fuel passage 121, and the joint 53 between the fuel recovery member 13 and the connecting member 14 is perpendicular to the axis of the fuel discharge passage 131. Is formed in. Since the fuel supplied from the common rail has a high pressure, the fuel supply passage 111 and the fuel passage 1 are
A very large force is applied to 21 by the pressure of the fuel. The force due to the fuel pressure is applied to the fuel supply passage 111 and the fuel passage 1.
21 is added to the radially outward direction. That is, the fuel supply path 11
1 and a force is applied in a direction of increasing the diameter of the fuel passage 121. Therefore, the joints 51, 52 and 53 are connected to the fuel supply passage 11
1, the fuel passage 121 and the fuel discharge passage 131 are formed so as to be perpendicular to the axes, so that the force due to the fuel pressure is applied to the joint portion
The members 1, 52 and 53 are not added in the direction of separating them. This improves the pressure resistance of the joint portions 51, 52, 53.

Next, a method of manufacturing the housing 10 will be described. As described above, the fuel supply member 11, the main body member 12, the fuel recovery member 13, and the connection member 14 are individually molded. The shapes of the fuel supply member 11, the main body member 12, the fuel recovery member 13, and the connecting member 14 are selected at the design stage according to the shape of the engine to be mounted, and each member is molded according to the designed shape. Alternatively, the fuel supply member 11, the main body member 12, the fuel recovery member 13, and the connection member 14 are prepared in advance in a plurality of shapes for each member as shown in FIG. In addition, a member having an appropriate shape is selected from each member group.

When the molding of the fuel supply member 11, the main body member 12, the fuel recovery member 13 and the connecting member 14 is completed, these members are joined. The fuel supply member 11, the main body member 12, the fuel recovery member 13, and the connection member 14 are molded as separate members, and therefore, it is necessary to join them after molding to form the housing 10 of the injector 1.
The joining is performed from a temporary joining stage and a main joining stage.

The fuel supply member 11, the main body member 12, the fuel recovery member 13 and the connecting member 14 are formed by forming, for example, cutting, polishing or forging. Also,
The fuel supply member 11, the main body member 12, the fuel recovery member 13, and the connection member 14 are molded, and the fuel supply member 11 has a fuel supply passage 111 and the main body member 12 has a fuel passage 12.
1, a housing hole 122 and a fuel passage 123, a fuel discharge passage 131 in the fuel recovery member 13, and a housing hole 141, a connection passage 142, a fuel pipe 143, a connection passage 144 and a fuel passage 145 in the connection member 14. These fuel supply path 111, fuel path 121, fuel discharge path 131,
The hole portions such as the connection passage 142 and the connection passage 144 are formed, for example, by forming a material such as a drill.

At the temporary joining stage, the molded members are joined while being positioned. As described above, the fuel supply passage 111 of the fuel supply member 11 and the connection passage 142 of the connection member 14, the connection passage 142 of the connection member 14 and the fuel passage 121 of the main body member 12, and the fuel passage 12 of the main body member 12.
3 and the connection passage 144 between the connection member 14 and the connection member 1
No. 4 connection passage 144 and fuel recovery member 13 fuel discharge passage 1
It is necessary to connect with 31. Therefore, positioning is required so that the passage of each member formed separately is connected to the predetermined passage of the other member.

In the temporary joining step, the pin member is fitted to either one of the two members in which the passages to be connected are formed in order to position each member. Here, joining of the main body member 11 and the connecting member 14 will be described as an example. When joining the main body member 11 and the connection member 14, the pin members 61 and 62 are fitted in the fuel passage 121 and the fuel passage 123 of the main body member 12, as shown in FIG. Further, the pin member may be fitted into the connection passage 142 and the connection passage 144 of the connection member 14. Pin member 6
1, 62 are fitted into the fuel passages 121, 123 formed in the main body member 11 by, for example, press fitting. Part of the pin members 61, 62 is fitted inside the fuel passages 121, 123, and the other part projects from the main body member 12. After the pin members 61 and 62 are fitted into the fuel passages 121 and 123 of the body member 12, the protruding pin members 61 and 62 and the connection passages 142 and 144 of the connection member 14 are connected.
Are fitted together. As a result, the fuel passages 121 and 123 of the main body member 12 and the connection passages 142 of the connection member 14,
144 is positioned through the pin members 61 and 62,
At the same time, the main body member 12 and the connecting member 14 are positioned. A pin member may be fitted into the accommodation hole 122 of the main body member 12 or the accommodation hole 141 of the connection member 14 for positioning.

As shown in FIG. 5, the fuel supply member 11 and the connection member 14, and the fuel recovery member 13 and the connection member 14 are pin members 63, as in the case of temporary joining of the main body member 12 and the connection member 14. It is temporarily joined while being positioned by 64. Also in this case, the pin member may be fitted into one of the passages formed in the two members to be joined. By temporarily joining the fuel supply member 11, the main body member 12, the fuel recovery member 13, and the connection member 14, the main body member 12, the fuel supply member 11, and the fuel recovery member 13 are connected to each other.
It is provisionally joined via 4.

When the temporary joining is completed, the main joining is performed on the joining portions 51, 52 and 53 of the temporarily joined members. The joint portions 51, 52 and 53 are joined by electron beam welding or diffusion joining. By using electron beam welding or diffusion bonding, the bonding portions 51, 52, 53 are bonded from the outer peripheral side to the inner peripheral side. Further, by using electron beam welding or diffusion bonding, the fuel supply member 11, the main body member 12, the fuel recovery member 13 and the connecting member 14 are seamlessly integrated at the joint portions 51, 52 and 53, and the housing 1
The same strength as when 0 is integrally molded is obtained.

When the main joining is completed, the pin members 61, 6
Removal of 2, 63, 64 is performed. Since the pin members 61, 62, 63, 64 are fitted during the temporary joining of the members,
When the main joining is completed, the pin members 61, 62, 63, 64 remain in the respective joining portions 51, 52, 53 as shown in FIG. That is, these pin members 61, 62,
Reference numerals 63 and 64 block each of the connected passages. Therefore, after the main joining is completed, it is necessary to remove the pin members 61, 62, 63, 64 remaining in these passages.
The pin members 61, 62, 63, 64 are removed by forming a material such as drilling. Pin members 61, 6
Since the total length of 2, 63, 64 is shorter than the total length of the passage formed in each member, for example, when drilling,
A drill can be easily inserted and removed from the end of the passage formed in each member.

As described above, according to the injector 1 according to the embodiment of the present invention, the housing 10 is divided into the fuel supply member 11, the main body member 12, the fuel recovery member 13 and the connecting member 14, so that the engine is divided. Also, the shapes of the fuel supply member 11, the main body member 12, the fuel recovery member 13, and the connection member 14 can be individually selected according to the shape of the surroundings to be mounted. Therefore, it is easy to change the design of the injector 1. Further, the fuel supply member 1
1, body member 12, fuel recovery member 13 and connection member 1
By dividing into four, each member can be molded, and the total length of the small holes forming the passages of each member is shortened, so that the injector 1 can be easily processed.

Joining portions 51, 52 of the fuel supplying member 11, the main body member 12, the fuel collecting member 13, and the connecting member 14,
53 is formed perpendicular to the axis of the passage that passes through the joint. Therefore, the force due to the pressure of the high-pressure fuel is
Joining parts 51, 5 without joining 1, 52, 53
The strength of 2, 53 can be increased.

Further, the joint portion 51 of the fuel supply member 11, the main body member 12, the fuel recovery member 13 and the connecting member 14,
52 and 53 are joined by electron beam welding or diffusion joining. Therefore, even when the fuel supply member 11, the main body member 12, the fuel recovery member 13, and the connection member 14 are formed as individual members, it is possible to ensure the same strength as when they are integrally formed.

According to the method of manufacturing the injector 1 according to the embodiment of the present invention, the pin members 61, 62, 6 are temporarily joined.
3 and 64 are fitted. As a result, the respective members are reliably positioned during the temporary joining, and the main joining is performed. Therefore, the positioning of each member is easy, and the processing accuracy of the injector 1 can be improved. Pin member 6
The lengths 1, 62, 63, 64 are shorter than the total length of the passages formed in the respective members, and can be easily removed.

Further, the fuel supply member 11, the main body member 12,
The fuel recovery member 13 and the connection member 14, and holes such as the fuel supply passage 111, the fuel passage 121, the fuel passage 123, the fuel discharge passage 131, the connection passage 142, and the connection passage 144 are processed by forming. for that reason,
Each member and passage can be easily processed.

As described above, in the embodiment of the present invention, the example in which the housing is divided into the four members of the fuel supply member, the main body member, the fuel recovery member and the connecting member has been described. However, for example, the main body member and the connection member may be integrally formed in advance, or the fuel supply member, the fuel recovery member, and the connection member may be integrally formed in advance. That is, it is also possible to configure the housing with two or more members and combine the two or more members for each model to configure the housing. As a result, the cost can be reduced by reducing the number of parts and the number of joints, and the strength can be further improved by reducing the number of joints.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing a housing of an injector according to an embodiment of the present invention, and is a view showing each member constituting the housing.

FIG. 2 is a schematic partial sectional view of an injector according to an embodiment of the present invention.

FIG. 3 is a schematic view showing a housing of an injector according to an embodiment of the present invention, showing a member group for each member and a housing in which the members are combined.

FIG. 4 is a schematic cross-sectional view showing the housing of the injector according to the embodiment of the present invention, showing the vicinity of the joint between the main body member and the connecting member.

FIG. 5 is a schematic cross-sectional view showing a housing of an injector according to an embodiment of the present invention, showing a state in which each member is temporarily joined.

[Explanation of symbols]

1 injector (fuel injection device) 10 housing 11 Body member 11 Fuel supply member 12 Body member 13 Fuel recovery member 14 Connection member 20 nozzle 23 Valve needle (movable member) 41 Control piston (movable member) 51, 52, 53 joints 61, 62, 63, 64 pin members 111 Fuel supply path 121 Fuel passage 123 Fuel passage 131 Fuel discharge path 142 Connection passage 144 connection passage

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Mamoru Urushizaki             1-1, Showa-cho, Kariya city, Aichi stock market             Inside the company DENSO (72) Inventor Michihiro Oshima             1-1, Showa-cho, Kariya city, Aichi stock market             Inside the company DENSO F-term (reference) 3G066 AA07 AB02 AC09 AD07 BA46                       BA61 CC03 CC05U CC14                       CD04 CE21

Claims (11)

[Claims] 1. A fuel supply section to which fuel is supplied from a common rail, a main body section capable of accommodating a movable member therein and a nozzle section being connectable to one end section thereof, and surplus fuel being the main body. A fuel injection device comprising: a fuel recovery unit that is discharged via a fuel injection unit; and a connection unit that connects the other end of the main body unit to the fuel supply unit and the fuel recovery unit, A fuel supply path for supplying fuel is formed, and a fuel supply member forming the fuel supply section and a fuel passage through which fuel supplied from the fuel supply path passes are formed, forming a main body section forming the main body section. A fuel discharge path for discharging excess fuel is formed, and a fuel recovery member that constitutes the fuel recovery section, and a connection path that connects the fuel supply path, the fuel path, and the fuel discharge path are formed, Contact A fuel injection apparatus characterized by comprising a connecting member constituting the part, the. 2. The shapes of the fuel supply member, the main body member, the fuel recovery member and the connection member are selected for each model, and the selected fuel supply member, the main body member and the fuel recovery member and the connection are selected. The fuel injection device according to claim 1, wherein the fuel injection device is joined to a member. 3. Any one of the fuel supply member, the main body member, the fuel recovery member, or the connection member is any other member of the fuel supply member, the main body member, the fuel recovery member, or the connection member. The fuel injection device according to claim 1, wherein the fuel injection device is integrally molded with the fuel injection device. 4. The joint between the fuel supply member, the main body member or the fuel recovery member and the connection member is perpendicular to the axis of the fuel supply passage, the fuel passage or the fuel discharge passage. The fuel injection device according to claim 1, 2, or 3. 5. The fuel supply member, the main body member, or the fuel recovery member and the connection member are joined by electron beam welding.
The fuel injection device according to claim 1. 6. The fuel according to claim 1, wherein the fuel supply member, the main body member or the fuel recovery member and the connecting member are joined by diffusion joining. Injection device. 7. The method of manufacturing a fuel injection device according to claim 1, wherein the fuel supply member, the main body member, the fuel recovery member and the connection member are molded, A component forming step of forming the fuel supply passage in the supply member, the fuel passage in the main body member, the fuel discharge passage in the fuel recovery section, and the connection passage in the connection member; the fuel supply member, the main body member And for positioning between the fuel recovery member and the connection member,
A positioning step in which a pin member is fitted into one of the passages formed in members to be mutually joined, and the fuel supply member, the main body member, the fuel recovery member, and the connection member are temporarily joined by the pin member. A joining step; a main joining step of joining the temporarily joined fuel supply member, the main body member, the fuel recovery member, and the connecting member to each other; the fuel supply passage, the fuel passage, and the fuel discharge passage; And a pin member removing step of removing the pin member remaining in the fuel injection device. 8. The method of manufacturing a fuel injection device according to claim 7, wherein the fuel supply member, the main body member or the fuel recovery member and the connection member are electron beam welded. 9. The method of manufacturing a fuel injection device according to claim 7, wherein the fuel supply member, the main body member or the fuel recovery member and the connection member are diffusion-bonded. 10. The fuel injection device according to claim 7, wherein the fuel supply member, the main body member, the fuel recovery member, and the connection member are formed by processing a blank. Manufacturing method. 11. The fuel supply passage, the fuel passage, the fuel discharge passage, and the connection passage are formed by processing a blank material. Manufacturing method of fuel injection device.