JP2501967Y2 - Fuel injection device for internal combustion engine - Google Patents

Description

TECHNICAL FIELD The present invention relates to a fuel injection device for an internal combustion engine equipped with an electromagnetic fuel injection valve for each cylinder, and more particularly to a multidirectional injection type fuel injector suitable for an intake multi-valve engine or the like. The present invention relates to an improvement using a fuel injection valve.

2. Description of the Related Art As a fuel injection valve for an internal combustion engine, there is known a so-called side-feed type valve having a fuel inlet on a side surface of a substantially cylindrical metal housing and taking in fuel from the surroundings. In this type, most of the fuel injection valve is mounted in a state that it is submerged in the fuel passage of the fuel gallery. That is, injector housings having a substantially cylindrical shape are formed at a plurality of locations in the fuel gallery, and fuel injection valves having upper and lower O-rings are fitted and mounted therein (for example, JP-A-59-59). 34473 publication).

Further, in recent years, various multi-directional injection type fuel injection valves capable of simultaneously injecting fuel in a plurality of directions have been proposed and partially put into practical use for application to an intake two-valve engine or the like.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention In the case of using the above-described multi-direction injection type fuel injection valve, it is necessary to mount each spray so that each spray is directed in a desired direction, that is, each intake port or each intake valve. However, in the side feed format mentioned above,
Due to the seal using the O-ring, it can be inserted into the injector housing in any rotational posture, and no mechanical positioning in the rotational direction is performed. For this reason, it is unavoidable to visually perform positioning in the rotational direction during assembly to the fuel gallery.

Therefore, the work efficiency of the assembling work is lowered, and the rotation direction of the fuel injection valve actually attached varies to some extent, which may adversely affect the engine performance.

Since the inner peripheral surface of the injector housing is usually machined in a concentric shape, providing a positioning projection or groove on this inner peripheral surface is complicated in structure and extremely costly. There is also a risk that the O-ring may be damaged.

Therefore, according to the present invention, fuel flows through a side-feed type multi-directional injection type electromagnetic fuel injection valve having a synthetic resin cap portion having a connector portion at a base end portion. The fuel injection valve is fitted and mounted in a substantially cylindrical injector housing provided in the fuel gallery, and a flange portion provided in the upper portion of the fuel injection valve is fitted in a step portion provided at the opening edge of the injector housing. An internal combustion engine that axially positions the fuel injection valve and axially presses the fuel injection valve by a cover that covers the upper end of the fuel injection valve and is screwed to the upper surface of the injector housing to fix the fuel injection valve in the injector housing. In the fuel injection device, a polygonal shape is formed on the upper surface of the cap portion in a plane that projects in the axial direction of the fuel injection valve and that is orthogonal to the axis. The convex portion is formed integrally with the cap portion, and a concave portion having a plurality of flat inner wall surfaces that fit with a plurality of side surfaces of the convex portion is formed inside the cover, and the convex portion and the concave portion are formed. The feature is that the fuel injection valve is positioned in the rotational direction by fitting.

Action In the above configuration, the protrusion on the upper surface of the cap portion and the recess on the inner side of the cover are fitted to each other to prevent relative rotation between them. Therefore, the fuel injection valve is positioned in the rotational direction by screwing the cover to a predetermined position of the injector housing.

Embodiment Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

5 and 6 show a fuel gallery 1 that constitutes a fuel injection device for an in-line four-cylinder engine.

The fuel gallery 1 has four injector housings 2, and the injector housings 2 are sequentially connected by a plurality of metal pipes 3. A connection pipe 4 serving as a fuel inlet is attached to one end, and a metal pipe 3a at the other end is bent into an L shape, and a pressure regulator 5 for adjusting the fuel pressure is attached here. There is.

As shown in FIG. 2, the injector housing 2 has a substantially cylindrical shape with an open upper surface, has a tapered portion 6 at the lower end, and has an opening 7 having a relatively small diameter formed at the center thereof. There is. Further, a stepped portion 8a is formed at the opening edge of the opening 8 at the upper end, and a flange portion 9 is formed extending from both left and right sides of the opening 8 (see FIG. 4). The inner peripheral surface is machined with relatively high precision.

As shown in FIG. 6, the fuel gallery 1 is fixed to the intake manifold 13 by fastening a bracket 10 provided on the metal pipe 3 portion with a bolt 12 via a synthetic resin insulator 11. At this time,
Tip of each injector housing 2 and intake manifold 13
An annular rubber insulator 14 is interposed between and. An L-shaped bracket 15 is also provided at the end of the metal pipe 3a on the pressure regulator 5 side, and is fixed by a bolt 12 via a synthetic resin insulator 11.

In the injector housing 2 shown in FIGS.
As shown in the figure, the electromagnetic fuel injection valves 21 are fitted and mounted.

The fuel injection valve 21 is of a type that injects fuel in two directions, has a metal housing part 22 having a solenoid (not shown) inside, has a plurality of injection holes at the tip, and has a center. Is roughly divided into a nozzle body 23 into which a slidable needle (not shown) is fitted and a cap portion 24 molded to cover the base end surface of the housing 22, and the upper portion of the housing portion 22 and the nozzle body 23. O-rings 25 and 26 are attached to the middle portions, respectively. Further, the cap portion 24 is provided with a flange portion 27 projecting in the radial direction, and a rectangular connector portion 28 projecting obliquely upward is integrally formed. The fuel inlet of the fuel injection valve 21 has an opening on the side surface of the housing portion 22, and the outside thereof is a filter 31.
Is covered.

In the state where the fuel injection valve 21 is inserted into the injector housing 2, the flange portion 27 at the upper end of the fuel injection valve 21 engages with the step portion 8a of the opening 8 and the nozzle body 23 portion at the front end opens at the lower end. It is designed to slightly project from the portion 7 and is pressed and held from above by a cover 30 fixed to the flange portion 9 of the injector housing 2 with a pair of screws 29. The cover 30 has a substantially semi-circular shape, and the connector portion 28
Is protruding upward. 32 is the cover 30 and the cap portion
It is a rubber insulator that is disposed between the insulator 24 and 24. The O-rings 25 and 26 seal the upper and lower ends of the injector housing 2, respectively.

Here, as shown in FIG. 4, on the upper surface of the cap portion 24 of the fuel injection valve 21, there is integrally formed a rectangular convex portion 33 having an appropriate height. Further, inside the cover 30, a concave portion 34 having a size capable of fitting with the convex portion 33 is formed. As shown in FIG. 3, the concave portion 34 has a rectangular shape with one side open, and the three inner wall surfaces corresponding to the remaining three sides fit relatively closely with the three side surfaces of the convex portion 33. It is like this. Reference numeral 35 is a housing portion for the insulator 32.

Therefore, according to the above configuration, the fitting of the convex portion 33 and the concave portion 34 positions the cover 30 and the fuel injection valve 21 in the relative rotational direction, and the cover 30 is fixed to the upper surface of the injector housing 2 by the screw 29. As long as it is fixed, the fuel injection valve
The rotation posture of 21 can be reliably maintained in a predetermined state.
Therefore, it is not necessary to adjust the rotation direction by visual inspection or the like at the time of assembling, the variation is reduced, and the injection direction can be obtained in the predetermined direction.

Further, since the convex portion 33 can be easily formed by resin molding, and the cover 30 is also originally formed in an irregular shape by aluminum die casting or the like, a protrusion or a groove is formed on the inner circumference of the injector housing 2. It can be carried out very easily and at low cost as compared with the case of processing etc.

EFFECTS OF THE INVENTION As is clear from the above description, according to the fuel injection device for an internal combustion engine of the present invention, the multi-direction injection type fuel injection valve can be mounted in the injector housing of the fuel gallery in a predetermined rotational posture. Therefore, fuel injection can be accurately performed in a predetermined direction. Further, since the positioning recess and protrusion are provided in the synthetic resin portion of the fuel injection valve and the cover screwed to the injector housing, the formation thereof is facilitated and the cost is not increased.

[Brief description of drawings]

FIG. 1 is a plan view showing an essential part of a fuel injection device according to the present invention, FIG. 2 is a sectional view of the same, and FIG. 3 is a rear view of a cover.
FIG. 4 is a plan view with the cover removed, FIG. 5 is a plan view of the entire fuel gallery, and FIG. 6 is a front view with the intake manifold mounted. 1 ... Fuel gallery, 2 ... Injector housing,
21 ... Fuel injection valve, 24 ... Cap part, 30 ... Cover,
33 ... convex, 34 ... concave.

Claims (1)

(57) [Scope of utility model registration request] 1. A substantially cylindrical shape in which a side-feed type multi-directional injection type electromagnetic fuel injection valve having a synthetic resin cap portion having a connector portion at its base end is provided in a fuel gallery through which fuel flows. Is fitted and mounted in the injector housing, and the flange portion provided at the upper portion of the fuel injection valve is fitted to the step portion provided at the opening edge of the injector housing to position the fuel injection valve in the axial direction. A fuel injection device for an internal combustion engine in which the fuel injection valve is axially pressed and fixedly held in the injector housing by a cover that covers the upper end of the fuel injection valve and is screwed to the upper surface of the injector housing. A convex portion that projects in the axial direction of the fuel injection valve and has a polygonal shape in a plane orthogonal to the axis is integrally formed with the cap portion. In addition, a concave portion having a plurality of flat inner wall surfaces that fit with the plurality of side surfaces of the convex portion is formed inside the cover, and by fitting the convex portion and the concave portion, A fuel injection device for an internal combustion engine characterized by being positioned.