JPH1144280A - Mounting structure of fuel injection valve for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To set the fuel injection outlet of a fuel injection valve near the combustion chamber side of an internal combustion engine without increasing a cost and lowering assembly ability and reliability. SOLUTION: A fuel feed cylinder part 14a protruding in a mounting hole 11a formed in an intake manifold 11 is arranged at a fuel delivery pipe 14 fixed at the intake manifold 11 fixed at the cylinder head 10 of an internal combustion engine. The fuel introduction port 17a of a fuel injection valve 17 is fitted in a liquidtight manner in the internal part of a fuel feed part and an internal protrusion part 12a engaged with an engaging part 17c formed on the outer periphery of the fuel injection valve 17 is formed on one end, a cylindrical member 12 having an external protrusion part 12b formed on the other end is engaged in an airtight manner in an annular gap S between the fuel feed cylinder part 14a and a mounting hole, and the external protrusion of the cylindrical member is nipped between the intake manifold 11 and the fixing part of the fuel delivery pipe 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mounting structure for a fuel injection valve of an internal combustion engine.

[0002]

2. Description of the Related Art As a conventional mounting structure for a fuel injection valve of 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 has a fuel injection port side provided with a fuel introduction hole 10 provided in correspondence with each cylinder of the intake manifold 101.
2 is inserted and attached via an insulator 103, and the fuel inlet side of the fuel injection valve 100 is inserted and attached via an O-ring 106 to a fuel supply port 105 of a fuel delivery pipe 104 fixed to the intake manifold 101,
A grommet made of an elastic material is arranged between the opposed end faces of the fuel injection valve 100 and the fuel supply port 105 of the fuel delivery pipe 104 so as to regulate the axial movement of the fuel injection valve 100.

[0003]

Incidentally, in recent years, in order to improve the combustion stability of an internal combustion engine and to reduce noise, for example,
There is an increasing demand to make the fuel injection port of the fuel injection valve as close as possible to the combustion chamber of the internal combustion engine (to move the fuel injection valve in the direction of the arrow in FIG. 4).

However, in order to meet this demand in a conventional structure, as shown in FIG.
04 is attached to the mounting hole of the intake manifold 101 via an O-ring 107,
The fuel injection port side of the fuel injection valve 100 is
5 must be inserted and attached via the insulator 103 to the support hole of the support portion 108 provided in the suction hole 105a. For this reason, 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 axial misalignment between the fuel injection port side and the fuel introduction port side of the valve 100 becomes large, and the sealing performance between the fuel introduction port side and the fuel delivery pipe 104 via the O-ring 106 is deteriorated. The reliability of the structure may be reduced. Also, the suction hole 105 of the cylinder head 105
The supporting portion 108 provided on the inner surface needs to be a separate member due to its manufacture. Not only does the cost of the mounting structure of the fuel injection valve increase due to the increase in the number of parts, but also the supporting portion 108 as a separate member is required. There is a possibility that the reliability may be further deteriorated due to falling off.

Therefore, the present invention provides a fuel injection valve mounting structure in which a fuel injection port of a fuel injection valve is connected to a combustion chamber side of an internal combustion engine without increasing manufacturing costs and lowering the assemblability and reliability. Is a technical issue.

[0006]

Means for Solving the Problems The technical means of the present invention taken to solve the above-mentioned problems is that a fuel delivery pipe fixed to an intake manifold fixed to a cylinder head of an internal combustion engine is formed on the intake manifold. A fuel supply cylinder is provided that protrudes into the mounting hole, and the fuel inlet side of the fuel injection valve is liquid-tightly fitted inside the fuel supply cylinder,
A cylindrical member having at one end an inward projection engaged with an engagement portion formed on the outer periphery of the fuel injection valve, and having an outward projection at the other end, the fuel supply cylinder portion and the mounting hole. The outer projection of the cylindrical member is sandwiched between the intake manifold and a fixed portion of the fuel delivery pipe.

According to the above-described means, the fuel injection valve is configured such that the outer protrusion of the tubular member is engaged with the intake manifold and the fuel delivery pipe while the inner protrusion of the tubular member is engaged with the outer circumferential engagement portion. It is attached by being clamped between the fixed parts with
Compared with the conventional mounting structure, the fuel injection port of the fuel injection valve can be made closer to the combustion chamber side of the internal combustion engine without increasing the manufacturing cost, lowering the assemblability and reliability.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a mounting structure of a fuel injection valve for an internal combustion engine according to the present invention will be described below with reference to the drawings.

In FIG. 1, an intake manifold 11 fixed to a cylinder head 10 of an internal combustion engine has a flat portion 11a provided in the vicinity of a mounting end on the cylinder head side thereof, and a mounting hole 11b corresponding to each cylinder (not shown). Are formed. O is located in an annular groove formed on the inner peripheral surface of the mounting hole 11b.
A ring 13 is fitted, and a cylindrical member 12 is fitted airtightly from the outside of the intake manifold 11 to the inner peripheral surface of the mounting hole 11 b via the O-ring 13.

As shown in FIGS. 1 and 3, an inner flange portion (inward projection) 12a is formed at one end of the cylindrical member 12 and projects inward in the radial direction. It protrudes radially outward and has an outer opening edge (flat portion 11) of the mounting hole 11b.
An outer flange portion (outer projection) 12b that contacts the a) is formed. In the flat part of the intake manifold 11, FIG.
And a resin delivery pipe 1 as shown in FIG.
4 is fixed by bolts 15, whereby the outer flange portion 12b of the tubular member 12 is sandwiched between the fuel delivery pipe 14 and the flat portion 11a. An annular groove for accommodating the outer flange portion 12b of the tubular member 12 may be formed on the surface of the fuel delivery pipe 14 facing the flat portion 11a.

The fuel delivery pipe 14 is formed with a fuel supply tube portion 14a in which a connector terminal is embedded.
A fuel introduction portion 17a of a fuel injection valve 17 is fitted in the fuel supply tube portion 14a in a liquid-tight manner via an O-ring 16 fitted in an annular groove formed on the outer periphery thereof. An annular groove into which the O-ring 18 is fitted is formed on the outer periphery of the fuel supply tube portion 14a. A radially inwardly projecting flange portion 17c is formed on the outer periphery of the fuel injection valve 17, and the flange portion 17c is in contact with the tip end surface of the fuel supply tube portion 14a. In this state, as described above, by fixing the fuel delivery pipe 14 to the intake manifold 11, the fuel supply tubular portion 14 a is airtightly fitted to the inner peripheral surface of the tubular member 12 via the O-ring 18. Then, the tubular member 12 is hermetically fitted into the annular gap S formed between the fuel supply tubular portion 14a and the mounting hole 11b.
Flange portion 17c is the inner flange portion 1 of the cylindrical member 12.
2a and the distal end surface of the fuel supply tube portion 14a, the outer flange portion 12b of the tubular member 12 is sandwiched and fixed between the fuel delivery pipe 14 and the intake manifold 11, and the fuel injection valve 17 is It is attached to the intake manifold 11. In this state, as shown in FIG. 1, the fuel ejection portion 17b of the fuel injection valve 17 is located in the suction hole 10a of the cylinder head 10.

As described above, according to the present embodiment, the fuel injection valve 17 is mounted on the outer periphery of the cylindrical member 12 with the inner flange portion 12a of the cylindrical member 12 engaged with the outer peripheral flange portion 17c. The flange portion 12b is sandwiched between the fixed portions of the intake manifold 11 and the fuel delivery pipe 14, whereby the axial and radial movements are restricted, and the flange portion 12b is mounted. Therefore, the fuel injection portion 17 of the fuel injection valve 17
Since it is not necessary to support the fuel injection valve 17b, the fuel injection portion 17b of the fuel injection valve 17 can be brought closer to the combustion chamber side of the internal combustion engine (not shown) in order to improve the combustion stability and reduce noise of the internal combustion engine. It is not necessary to provide a separate member to the cylinder head 10 to increase the number of parts and support the fuel ejection portion 17b as in the mounting structure of (1).

The fuel injection valve 17 has a fuel introduction section 17.
Because it is supported only on the a side, there is no axial displacement,
The sealing performance of the O-ring 16 can always be kept good. Further, as described above, the fuel delivery pipe 14 can be fixed to the intake manifold 11 and the fuel injection valve 17 can be attached to the intake manifold 11 at the same time, so that good assemblability can be secured.

[0014]

As described above, according to the present invention, in the fuel injection valve, the outer projection of the cylindrical member engages with the outer projection to engage the outer projection with the inner projection. Since it is attached to the intake manifold by being sandwiched between the fixed parts of the manifold and the fuel delivery pipe, the fuel cost can be increased without increasing the manufacturing cost, lowering the assemblability and reliability compared to the conventional mounting structure. The fuel injection valve can be mounted so that the fuel injection port of the injection valve is closer to the combustion chamber side of the internal combustion engine, which can contribute to improvement of combustion stability of the internal combustion engine and reduction of noise.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a mounting structure of a fuel injection valve of 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 of assembling the attachment structure of FIG. 1;

FIG. 4 is a cross-sectional view of a conventional fuel injector mounting structure for an internal combustion engine.

FIG. 5 is a sectional view of a conventional fuel injector mounting structure for an internal combustion engine.

[Explanation of symbols]

 Reference Signs List 10 Cylinder head 11 Intake manifold 11b Mounting hole 12 Cylindrical member 12a Inner flange (inward projection) 12b Outer flange (outward projection) 14 Fuel delivery pipe 14a Fuel supply cylinder 17 Fuel injection valve 17a Fuel Introducing section 17b Fuel ejection section 17c Flange section (engaging section) S annular gap

Claims (1)

[Claims] 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 that projects into a mounting hole formed in the intake manifold. A fuel injection valve side of the fuel injection valve is fitted therein in a liquid-tight manner, and has an inward projection at one end that engages with an engagement portion formed on the outer periphery of the fuel injection valve. A tubular member having an outward protrusion is hermetically fitted into an annular gap between the fuel supply tubular portion and the mounting hole, and the outward protrusion of the tubular member is connected to the intake manifold and the fuel delivery. A mounting structure for a fuel injection valve of an internal combustion engine sandwiched between fixed portions of a pipe.