JP3807040B2 - Mounting structure of fuel injection valve for internal combustion engine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a fuel injection valve mounting structure for an internal combustion engine.
[0002]
[Prior art]
As a conventional fuel injection valve mounting structure for an internal combustion engine, for example, a structure disclosed in Japanese Utility Model Publication No. 55-26530 is known. As shown in FIG. 4, the fuel injection valve 100 is inserted into a fuel introduction hole 102 provided corresponding to each cylinder of the intake manifold 101 via an insulator 103 and attached thereto, as shown in FIG. The fuel introduction port side of the injection valve 100 is inserted and attached to the fuel supply port 105 of the fuel delivery pipe 104 fixed to the intake manifold 101 via the O-ring 106, and the fuel supply port 105 of the fuel injection valve 100 and the fuel delivery pipe 104 is attached. A grommet made of an elastic material is disposed between the opposed end surfaces of the fuel injection valve 100 to restrict the axial movement of the fuel injection valve 100.
[0003]
[Problems to be solved by the invention]
By the way, in recent years, in order to improve combustion stability of an internal combustion engine, reduce noise, and the like, the fuel injection port of the fuel injection valve is desired to be as close as possible to the combustion chamber of the internal combustion engine (the fuel injection valve is moved in the direction of the arrow in FIG. 4). There is a growing demand for this.
[0004]
However, in order to meet this demand in the conventional structure, as shown in FIG. 5, the outer periphery of the fuel supply port 105 of the fuel delivery pipe 104 is attached to the attachment hole of the intake manifold 101 via the O-ring 107 and fuel injection is performed. The fuel injection port side of the valve 100 must be inserted into the support hole of the support portion 108 provided in the suction hole 105a of the cylinder head 105 via the insulator 103 and attached. For this reason, since the mounting posture of the fuel injection valve 100 is determined by the three members of the fuel delivery valve 104, the intake manifold 101, and the cylinder head 105, the assembling property of the fuel injection valve 100 is deteriorated and the fuel injection is performed. Axis misalignment between the fuel injection port side and the fuel introduction port side of the valve 100 becomes large, the sealing performance between the fuel introduction port side and the fuel delivery pipe 104 via the O-ring 106 deteriorates, and the fuel injection valve is attached. The reliability of the structure may be reduced. Further, the support portion 108 provided on the inner surface of the suction hole 105a of the cylinder head 105 needs to be a separate member in its manufacture, and not only increases the cost of the fuel injection valve mounting structure by increasing the number of parts, There is a risk that the reliability may be further deteriorated due to the dropping of the support portion 108 as a separate member.
[0005]
Therefore, according to the present invention, the fuel injection valve mounting structure brings the fuel injection port of the fuel injection valve closer to the combustion chamber side of the internal combustion engine without causing an increase in manufacturing cost, a decrease in assemblability and reliability. Is the technical issue.
[0006]
[Means for Solving the Problems]
The technical means of the present invention taken in order to solve the above-described problem is a fuel that enters a fuel delivery pipe fixed to an intake manifold fixed to a cylinder head of an internal combustion engine into a mounting hole formed in the intake manifold. A supply cylinder portion is provided, and the fuel inlet side of the fuel injection valve is liquid-tightly fitted inside the fuel supply cylinder portion, and is engaged with an engagement portion formed on the outer periphery of the fuel injection valve. A cylindrical member having a projecting portion at one end and an outer projecting portion at the other end is hermetically fitted into an annular gap between the fuel supply tubular portion and the mounting hole, and the tubular member The outward projection is sandwiched between the intake manifold and the fixed portion of the fuel delivery pipe.
[0007]
According to the above-described means, the fuel injection valve is fixed to the intake manifold and the fuel delivery pipe with the outer protrusion of the cylindrical member engaged with the outer peripheral engagement portion of the fuel injection valve. Compared to the conventional mounting structure, the fuel injection port of the fuel injection valve is connected to the combustion chamber of the internal combustion engine without incurring an increase in manufacturing cost, assembly, and reliability. It can be close to the side.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of a fuel injection valve mounting structure for an internal combustion engine according to the present invention will be described with reference to the drawings.
[0009]
In FIG. 1, an intake manifold 11 fixed to a cylinder head 10 of an internal combustion engine is provided with mounting holes 11b corresponding to respective cylinders (not shown) in a flat portion 11a provided in the vicinity of the cylinder head side mounting end. ing. An O-ring 13 is fitted in an annular groove formed in the inner peripheral surface of the mounting hole 11b, and the tubular member 12 is airtightly sealed through the O-ring 13 on the inner peripheral surface of the mounting hole 11b. It is fitted from the outside of the intake manifold 11.
[0010]
As shown in FIGS. 1 and 3, an inward flange portion (inward protrusion) 12a that protrudes radially inward is formed at one end of the cylindrical member 12, and a radially outer portion is formed at the other end. An outer flange portion (outward protruding portion) 12b that protrudes in the direction and contacts the outer opening edge portion (flat portion 11a) of the mounting hole 11b is formed. A resin fuel delivery pipe 14 as shown in FIGS. 2 and 3 is fixed to the flat portion of the intake manifold 11 with bolts 15, whereby the outer flange portion 12 b of the tubular member 12 is made of fuel. It is clamped between the delivery pipe 14 and the flat part 11a. An annular groove in which the outer flange portion 12b of the cylindrical member 12 is accommodated may be formed on the surface of the fuel delivery pipe 14 facing the flat portion 11a.
[0011]
The fuel delivery pipe 14 is formed with a fuel supply cylinder part 14a in which a connector terminal is embedded, and an O-ring 16 fitted in an annular groove formed on the outer periphery of the fuel supply cylinder part 14a. The fuel introduction portion 17a of the fuel injection valve 17 is fitted in a liquid-tight manner. An annular groove into which the O-ring 18 is fitted is formed on the outer periphery of the fuel supply cylinder portion 14a. A flange portion 17c projecting radially inward is formed on the outer periphery of the fuel injection valve 17, and the flange portion 17c is in contact with the front end surface of the fuel supply cylinder portion 14a. In this state, as described above, the fuel delivery pipe 14 is fixed to the intake manifold 11, so that the fuel supply cylinder portion 14 a is airtightly fitted to the inner peripheral surface of the cylindrical member 12 via the O-ring 18. (The tubular member 12 is airtightly fitted in the annular gap S formed between the fuel supply cylinder portion 14a and the mounting hole 11b), and the flange portion 17c of the fuel injection valve 17 is connected to the tubular member 12. While being sandwiched between the inner flange portion 12a and the front end surface of the fuel supply cylinder portion 14a, the outer flange portion 12b of the cylindrical member 12 is sandwiched and fixed between the fuel delivery pipe 14 and the intake manifold 11, and the fuel is supplied. An injection valve 17 is attached to the intake manifold 11. In this state, as shown in FIG. 1, the fuel injection portion 17 b of the fuel injection valve 17 is positioned in the suction hole 10 a of the cylinder head 10.
[0012]
As described above, according to the present embodiment, the fuel injection valve 17 has the outer flange portion of the tubular member 12 in a state where the inner flange portion 12a of the tubular member 12 is engaged with the outer flange portion 17c. 12b is clamped between the fixed portions of the intake manifold 11 and the fuel delivery pipe 14, so that the axial movement and the radial movement are restricted and attached. Therefore, since it is not necessary to support the fuel injection portion 17b of the fuel injection valve 17, the combustion of the internal combustion engine (not shown) is not shown in order to improve the combustion stability of the internal combustion engine and reduce the noise. Even if it is brought closer to the chamber side, it is not necessary to provide a separate member in the cylinder head 10 and increase the number of parts to support the fuel ejection part 17b as in the conventional mounting structure.
[0013]
In addition, since the fuel injection valve 17 is supported only on the fuel introduction portion 17a side, the sealing performance by the O-ring 16 can always be kept good without causing an axis deviation. Further, as described above, since the fuel delivery pipe 14 can be fixed to the intake manifold 11 and at the same time the fuel injection valve 17 can be attached to the intake manifold 11, it is possible to ensure good assembly.
[0014]
【The invention's effect】
As described above, according to the present invention, the fuel injection valve is configured such that the outer protrusion of the cylindrical member is engaged with the outer periphery engaging portion, and the outer protrusion of the cylindrical member is the intake manifold and the fuel delivery pipe. Is attached to the intake manifold by being sandwiched between the fixed portion and the fuel injection valve of the fuel injection valve without incurring an increase in manufacturing cost, a decrease in assemblability and reliability as compared with the conventional mounting structure. A fuel injection valve can be attached so that the outlet is close to the combustion chamber side of the internal combustion engine, which can contribute to improvement in combustion stability and noise reduction of the internal combustion engine.
[Brief description of the drawings]
FIG. 1 is a sectional view showing an embodiment of a fuel injection valve mounting structure for an internal combustion engine according to the present invention.
FIG. 2 is a perspective view of the fuel delivery pipe of FIG.
FIG. 3 is an explanatory view showing a method for assembling the mounting structure of FIG. 1;
FIG. 4 is a cross-sectional view of a conventional fuel injection valve mounting structure for an internal combustion engine.
FIG. 5 is a cross-sectional view of a conventional fuel injection valve mounting structure for an internal combustion engine.
[Explanation of symbols]
10 Cylinder head 11 Intake manifold 11b Mounting hole 12 Tubular member 12a Inner flange (inner protrusion)
12b Outer flange (outward projection)
14 Fuel delivery pipe 14a Fuel supply cylinder part 17 Fuel injection valve 17a Fuel introduction part 17b Fuel injection part 17c Flange part (engagement part)
S annular gap

Claims (1)

A fuel delivery pipe fixed to an intake manifold fixed to a cylinder head of an internal combustion engine is provided with a fuel supply cylinder portion that enters into a mounting hole formed in the intake manifold, and a fuel injection valve is provided inside the fuel supply cylinder portion The fuel inlet side of the fuel injection valve is fitted in a liquid-tight manner, and has an inward projection that engages with an engagement portion formed on the outer periphery of the fuel injection valve at one end, and an outer projection at the other end. A cylindrical member having a cylindrical shape between the fuel supply pipe and the mounting hole, and an outer protrusion of the cylindrical member between the intake manifold and the fixed part of the fuel delivery pipe. A fuel injection valve mounting structure for an internal combustion engine sandwiched between two.

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