JP3569944B2 - Fuel injection device - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to a fuel injection device that supplies air controlled by a throttle valve to an engine via an intake passage and injects and supplies fuel controlled by a fuel injection valve toward air flowing in the intake passage.
[0002]
[Prior art]
FIG. 3 shows a conventional fuel injection device. Explaining with reference to the drawing, the fuel injection device includes an intake pipe 60, an air chamber 70, and an intake control pipe 80. The air chamber 70 has an opening 70B formed in an upper side wall 70A in the figure. It has a closed shape, and an intake control pipe 80 is connected to the opening 70B via a connecting pipe 71. An intake control passage 81 penetrates the intake control pipe 80, and the opening area of the intake control passage 81 is defined by a throttle valve 83 attached to a shaft 82 rotatably supported by the intake control pipe 80. Controlled. On the other hand, a plurality of intake paths 60A are formed in the intake pipe 60. One end of the intake path 60A opens to the air chamber 70, and the other end opens to the engine E. Reference numeral 90 denotes a fuel injection valve that opens into each intake passage 60A of the intake pipe 60.
[0003]
The throttle valve 83 is opened and closed by the driver, and air flowing through the intake control passage 81 controlled by the throttle valve 83 flows into the air chamber 70 through the connecting pipe 71, Is supplied to the engine E through each intake passage 60A of the intake pipe 60. On the other hand, properly controlled fuel is injected into each intake passage 60A from the fuel injection valve, whereby the fuel is mixed with the air flowing through the intake passage 60A, and the mixture containing fuel and air is thereby mixed. Is supplied to the institution E.
[0004]
[Problems to be solved by the invention]
According to such a conventional fuel injection device, the air chamber 70 has a closed chamber shape, and openings are formed in a plurality of directions of the air chamber 70 (the opening 70B and the intake passage 60A are opened). Therefore, it is difficult to manufacture the air chamber 70 including the intake pipe 60. For example, in the die-casting method using a metal material (aluminum alloy, zinc alloy, etc.) and the injection molding method using a synthetic resin material (nylon, etc.), molding is impossible due to the undercut portion in the air chamber 70. In addition, in the casting method using a sand mold, it is possible to manufacture, but it takes a lot of time to manufacture each piece, and there is a difficulty in mass production. There is a problem that it is difficult to make the wall surface smooth and hinders the air flow.
[0005]
On the other hand, according to the connection between the intake control pipe 80 and the air chamber chamber 70 using the connection pipe 71, the distance between the injection hole 90 of the fuel injection valve and the shaft 82 supporting the throttle valve 83 is increased, This has the disadvantage that the lubricating action of the fuel is reduced, and increases the number of parts and the number of assembling steps, which is not preferable.
[0006]
[Object of the invention]
SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and provides an inexpensive manufacture of a fuel injection device including an intake pipe, an air chamber, and an intake control pipe, and improves a lubrication effect of fuel on a shaft to which a throttle valve is attached. The purpose is to let them.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, a fuel injection device according to the present invention includes: an intake control pipe having a throttle valve in an intake control passage; an air chamber connected to an intake control passage downstream of the throttle valve; An opening is provided in the air chamber chamber, and the other end is provided with an intake pipe section having a plurality of intake paths connected to the engine, and the air flowing in the intake control passage is controlled by a throttle valve to be supplied into the air chamber chamber. In the fuel injection device that supplies the air in the air chamber chamber to the engine through a plurality of intake paths and injects fuel from the fuel injection valve into the air flowing through the intake path , an opening is formed in the air chamber chamber. A bottomed box-shaped recess opening toward the opening at one end through the side wall from the bottom formed, and the side wall is integrally provided with an intake control pipe section orthogonal to the side wall and inside the intake control pipe section. Sucked in A first air chamber portion directly opening one end of the control passage toward the side wall and directly opening the other end to the atmosphere; and a bottomed box-shaped concave second air chamber closing an opening of the first air chamber portion. On the other hand, the intake pipe portion is formed such that an intake passage is penetrated in a horizontal direction from one end side to the other end side, and one end of the intake passage is formed in an opening at the bottom of the air chamber chamber. And the other end is connected to the engine.
[0008]
[Action]
The air chamber chamber has a first air chamber portion having an intake control pipe portion penetrated through the intake control passage, a bottom opening, and a second air chamber closing the opening of the first air chamber portion. The first air chamber and the second air chamber have no undercut, so that the first air chamber and the second air chamber do not have an undercut, so that die casting and injection molding can be performed, and an air chamber having an air intake control pipe is provided. Manufacturing cost can be reduced. Further, since the mounting flange portions of the first air chamber portion and the second air chamber portion facing each other may be simply joined, the assembly can be performed at low cost. Further, since the shaft on which the throttle valve is mounted is disposed in the intake control passage in the intake control pipe portion directly protruding from the first air chamber, it is possible to effectively obtain the lubrication by the fuel injected from the fuel injection valve. it can.
[0009]
【Example】
Hereinafter, a first embodiment of a fuel injection device according to the present invention will be described with reference to FIGS. 1 is a longitudinal sectional view, and FIG. 2 is a transverse sectional view taken along line XX of FIG. Reference numeral 1 denotes a first air chamber portion. The first air chamber portion 1 has a bottomed box-shaped concave shape, one end A side (left side in the figure) is opened with an opening 2, and the other end B side (FIG. in has a bottom 3 on the right side), the side walls 4 toward one end a side of the outer periphery of the bottom portion 3 is formed to protrude, the openings are formed in an end portion of the one end a side wall 4.
[0010]
At the outer periphery (the right end face in the figure) of the bottom 3, a flat mounting flange 5 is formed on the side of the intake pipe, and the bottom 3 is provided inside the first air chamber 1 and with the mounting flange 5 on the side of the intake pipe. The opening 6 penetrating through is formed. In this embodiment, two openings 6 are formed. In addition, a mounting flange 7 on the side of the second air chamber, which forms a flat surface, is formed on the entire periphery of the opening 2 on one end A side of the side wall 4.
[0011]
The side wall 4 is integrally formed with an intake control pipe portion 8 which projects perpendicularly to the side wall 4 and outwardly (in this example, upward in the drawing). An intake control passage 9 is provided, one end of which directly opens into the first air chamber portion 1 and the other end which opens directly to the atmosphere (opens upward in the figure ).
[0012]
When the first air chamber 1 is formed by die casting or injection molding using a synthetic resin material, the outer shape portion including the intake control pipe portion 8 and the inner bottomed box-shaped concave portion , the opening portion 2, 6 is performed by a movable mold and a fixed mold, and the intake control passage 9 is formed by a movable core that moves vertically in the figure. This is done because there is no undercut portion for the mold and the core based on the structure of the first air chamber portion 1 described above.
[0013]
Reference numeral 10 denotes an intake pipe section having the following configuration. Reference numeral 11 denotes a flat engine-side mounting flange provided on the other end B side (the right end in the drawing) of the intake pipe section 10, and 12 denotes a flat mounting flange provided on the one end A side (the left end in the drawing) of the intake pipe section 10. One end 13B of an intake path 13 formed in the intake pipe section 10 is open to the mounting flange 12 on the air chamber chamber side, and the other end 13C is a mounting flange 11 on the engine side. Open to In the present embodiment, four intake paths 13 are arranged, but the number and arrangement of the intake paths 13 are appropriately designed according to the engine to be mounted. Further, the separating wall 13A of the adjacent intake passage 13 may be extended to the end face of the mounting flange 12 on the side of the air chamber, and the separating wall 13A is shown by a dashed line in the figure.
[0014]
When the intake pipe portion 10 is formed by die casting or injection molding using a synthetic resin material, the outer shape thereof is performed by a movable mold and a fixed mold, and the intake passage 13 moves rightward in the drawing. It is performed by a core and a movable core that moves to the left. This is done because there is no undercut portion for the mold and the core based on the structure of the intake pipe section 10 described above.
[0015]
Reference numeral 14 denotes a second air chamber, which has a bottomed box-shaped concave shape, and has an opening 15 on the other end B side (right side in the figure) and a bottom section 16 on one end A side (left side in the figure). And a flat mounting flange 17 on the first air chamber portion side is formed all around the opening 15 at the other end B.
[0016]
When the second air chamber portion 14 is formed by die casting or injection molding using a synthetic resin material, it is performed by a movable mold and a fixed mold. This is done because there is no undercut portion for the mold based on the structure of the second air chamber portion 14 described above. As described above, the first air chamber 1, the intake pipe 10, and the second air chamber 14 having the intake control pipe 8 are specially prepared.
[0017]
The first air chamber 1, the intake pipe 10, and the second air chamber 14 are assembled as follows. First, the mounting flange 17 on the first air chamber portion side of the second air chamber portion 14 is arranged on the mounting flange 7 on the second air chamber portion side of the first air chamber portion 1. 17 are joined. This joining may be performed by any joining method such as screwing with a screw, bonding with an adhesive, a clip made of an elastic metal material, fitting with a hole and a locking projection. According to the above, the air chamber chamber C which forms a closed shape by a bottomed box-recess-shaped first air chamber portion 1 of the bottomed box-type recesses form a second air chamber 14 is formed.
[0018]
Next, the first air chamber section 1 and the intake pipe section 10 are assembled as follows. That is, the mounting flange 12 on the side of the air chamber of the intake pipe section 10 is arranged on the mounting flange 5 on the side of the intake pipe section of the first air chamber section 1, and in this state, the two flanges 11, 12 are similar to the above. Joining by the following method. According to the above, the first air chamber section 1 and the intake pipe section 10 are integrally joined, and each intake path 13 of the intake pipe section 10 is connected to each opening section 6 of the first air chamber section 1 opposed thereto. It will open.
[0019]
The shaft 82 and the throttle valve 83 are disposed in the intake control passage 9 of the intake control pipe section 8, and the fuel injection valve J is disposed in the intake pipe section 10. I do. The assembling of the shaft 82, the throttle valve 83, and the fuel injection valve J may be performed when the first air chamber unit 1 and the intake pipe unit 10 are assembled separately, or after assembling them.
[0020]
According to the fuel injection device is assembled as described above, the amount is controlled by the throttle valve 83 is air flowing through the intake control passage 9 flows into the air chamber chamber C, air in the air chamber chamber C is the The opening 6 is diverted by the intake passages 13 and supplied to the engine. On the other hand, the fuel injected from the fuel injection valve J injects and controls fuel directed toward the air flowing through the intake passages 13. Then, the operation of the engine is satisfied.
[0021]
In addition, the intake control pipe section 8 may protrude from the side wall of the second air chamber section 14 at right angles to the side wall.
[0022]
【The invention's effect】
According to the above-described fuel injection device of the present invention, the following special effects can be obtained. (1) The first air chamber portion and the second air chamber portion each having an intake control passage and an opening have an undercut portion for manufacturing a mold and a core used in die casting and injection molding. Therefore, they can be manufactured by die-casting or injection molding, and can be manufactured extremely easily and efficiently, thereby greatly reducing the manufacturing cost. (2) The first air chamber section, the second air chamber section, and the intake pipe section can be joined simply by overlapping flanges facing each other and joining them. In addition, the joining is performed by a commonly used joining method. The fuel injection device can be used very easily, and the assembling cost can be suppressed at a low cost. The fuel injection device can be provided at a low cost in combination with the reduction in the manufacturing cost of each of the above-mentioned components. (3) Since the shaft is directly disposed in the intake control passage protruding from the side wall of the first air chamber without any connection pipe, the shaft can be disposed in the vicinity of the air chamber. According to this, when the fuel injected from the fuel injection valve returns to the air chamber chamber due to the intake inertia, the shaft is efficiently lubricated by the fuel, and the rotation of the shaft is extended over a long period of time. Can be kept stable across. In particular, the present invention is suitable for a fuel injection device mounted on an outboard motor engine used at sea and used at sea when the air containing salt flows down in the intake control passage.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing one embodiment of a fuel injection device according to the present invention.
FIG. 2 is a cross-sectional view taken along line XX of FIG.
FIG. 3 is a longitudinal sectional view of a conventional fuel injection device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 1st air chamber part 2 opening part 3 bottom part 4 side wall 5 mounting flange 6 side of intake pipe part 6 opening part 7 mounting flange 8 side of air chamber part 8 intake control pipe part 9 intake control passage 10 intake pipe part 11 engine side Mounting flange 12 of the air chamber chamber side mounting flange 13 suction path 14 second air chamber part 15 opening 16 bottom part 17 first air chamber part side mounting flange 82 shaft 83 throttle valve

Claims (1)

An intake control pipe having a throttle valve in the intake control passage, an air chamber chamber connected to the intake control passage downstream of the throttle valve, one end opening to the air chamber chamber, and the other end connected to the engine. An intake pipe section having a plurality of intake passages, the air flowing in the intake control passage is controlled by a throttle valve to be supplied to the air chamber, and the air in the air chamber is supplied to the engine through the plurality of intake passages. In a fuel injection device that supplies and injects fuel from a fuel injection valve to air flowing through an intake passage, an air chamber chamber C is connected to one end A side via a side wall 4 from a bottom 3 where an opening 6 is formed. It is formed in the shape of a box with a bottom that opens toward the opening 2, and the side wall is integrally provided with an intake control pipe section 8 orthogonal to the side wall 4, and the air intake bored in the intake control pipe section 8. One end of the control passage 9 faces the side wall 4 Directly open Te, a first air chamber portion 1 which is open to the atmosphere and other end directly
And a second air chamber portion 14 having a box-shaped concave shape with a closed bottom that closes the opening 2 of the first air chamber portion 1. On the other hand, the intake pipe portion 10 extends from one end A side to the other end B side. The air intake passage 13 is formed so as to penetrate in a horizontal direction, one end 13B of the air intake passage is connected to the opening 6 of the bottom 3 of the air chamber C, and the other end 13C is connected to the engine. Fuel injection device.

Images