JPH03164564A - Multi-way injection type injector - Google Patents

Abstract

PURPOSE:To improve fuel atomizing performance by dividing a branch type injection passage in an adaptor disposed on the downstream side of a fuel injection nozzle into plural injected flow passage parts by a protruding part protruding from the flank, thereby reducing the adhesion of fuel to the wall surface. CONSTITUTION:Inside a sleeve-like injector body 2 provided with a fuel injection nozzle 1 at the center of one end part thereof, a needle valve 4 provided with a pintle part 3 at its tip is slidably mounted in the state of protruding from the fuel injection nozzle 1. The tip of the body 2 is provided with an adaptor 8 forming an injection passage 5 for branching fuel spray flow. In this case, the injection passage 5 is formed into approximately elliptic shape in the cross section, and a pair of protruding parts 9a, 9b are formed from both side faces on its minor axis side toward the center. The fuel spray flow therefore runs smoothly along the respective protruding parts 9a, 9b, thus reducing the adhesion of fuel to the wall surface. As a result, fuel atomizing performance is improved.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to an injector used in a multi-valve internal combustion engine having a plurality of intake valves, particularly an injector in which a jet branching type adapter is attached to an electromagnetic injection valve. This invention relates to a directional injector.

(Prior Art) As an injector for injecting fuel into an engine, etc., a bottle-type injection valve is used, which is equipped with a fuel injection hole and a needle valve inserted into the fuel injection hole. 2. Description of the Related Art A multidirectional injector is conventionally known, which is equipped with a jet branch type adapter having an injection passage whose downstream side is divided into a plurality of injection holes.

FIG. 6 is a sectional view of the tip of this type of conventional multidirectional injector, and FIG. 7 is a bottom view.

This conventional injector is equipped with a sleeve-shaped body 2 having a fuel injection hole 1 at the center of the end, and inside this body 2 is a needle valve 4 having a bottle part 3 at its tip. 2 fuel injection holes! Further, an adapter 6 is provided which is slidably attached so as to protrude from the fuel injection hole 1, and which forms a branch type injection passage 5 that branches the spray flow into two directions on the downstream side of the fuel injection hole 1. The downstream side of the injection passage 5 of the adapter 6 is branched into two directions at a predetermined angle around a branch 7 on the axis of the fuel injection hole I, and forms two injection holes 5a and 5b that open at the lower end surface. .

In the injector having such a structure, when the two dollar valve 4 is opened, fuel is injected as a spray from the annular gap around the bottle part 3. Then, the spray stream hits the branch part 7 of the adapter 6 and is split into two directions, flows downstream through each of the injection holes 5a and 5b, and fuel is injected into each of the 2g intake valves.

(Problems to be Solved by the Invention) In the conventional injector described above, the injection passage on the adapter side is branched into a plurality of branch passages at a downstream position on the valve axis, and the spray flow atomized by the bottle hits the branch part. A phenomenon in which the spray is divided into multiple streams and sprayed in each direction at a predetermined angle, but at that time, the spray streams collide with the branch and flow along the wall, causing adhesion to the wall and increasing the particle size. As a result, a problem has arisen in that the spray, which has been atomized by the bottle and is in a good atomized state, cannot be allowed to flow into the combustion chamber in that good atomized state.

This invention was made in view of the above problems, and
To reduce the adhesion of fuel particles to the wall surface when a spray stream is branched into multiple directions within an adapter in a multi-directional injector, and to allow the spray stream to flow downstream in a good atomized state. The purpose is to

(Means for Solving the Problems) A multidirectional injector according to the present invention includes a fuel injection hole and a valve that controls opening and closing of the fuel injection hole, and forms a branched injection passage downstream of the fuel injection hole. In a multi-directional injector equipped with an adapter, the jet flow passage of the adapter is made into a single hole type, eliminating the branching part on the valve axis line, and the jet flow passage is substantially in the downstream side by a convex part formed protruding from the side. It is characterized by being divided into a plurality of jet passages, and with this configuration, the above object has been achieved.

(Function) The jet flow passage of the adapter is a single-hole type, and this jet flow passage is substantially divided into a plurality of jet flow branching holes by a convex portion formed protruding from the side, so that the jet flow is branched on the valve axis. The spray stream is divided into a plurality of directions and flows.

At this time, since there is no branch part on the valve axis where the spray flow collides, the atomized spray flow flows downstream with the fuel having a small particle size and in a good atomized state.

(Example) Examples will be described below based on the drawings.

FIG. 1 is a longitudinal cross-sectional view of the tip of a multidirectional injector according to an embodiment of the present invention, and FIG.
A line sectional view, and FIG. 3 is an enlarged perspective view of section B in FIG. 2. The multi-directional injector of this embodiment, like the conventional device shown in FIG. A needle valve 4 having a needle valve 4 is slidably mounted with its bottle portion 3 protruding into the fuel injection hole l of the body 2.

An adapter 8 is provided at the tip of the body 2 to form a single-hole injection passage 5 for branching the spray stream into two directions on the downstream side of the fuel injection hole 1. The jet passage 5 of this adapter 8 has a substantially elliptical cross-sectional shape, and has a pair of convex portions 9a extending from both sides of the short axis toward the center.
, 9b are formed protrudingly.

FIG. 4 shows the structure of the injection passage 8.
a) is a top view, (b) is a sectional view taken along line bb, (c)
is a sectional view taken along line c-c. As shown in these figures, the substantially elliptical shape of the jet flow passage 5 itself is tapered in cross section from the upper end side to the outlet side in order to simplify resin molding. The pair of convex portions 9a and 9b are formed by a radius, and the radius of the radius, that is, the protrusion distance from the convex shape formation reference line indicated by the dashed line T in FIG. When R1 is R1, and rz is that of exit elevation 1, it is set so that R,>R. In addition, the convex shape formation reference line T itself is assumed to be inclined with respect to the valve axis Y, as shown in FIG.
The inclination angle θ shown in is set to 0°≦0. The diameter of the circle inscribed in the tops of the convex portions 9a and 9b on the most downstream end surface of the adapter 8 is set to satisfy 0<D≦1.5 mm.

In the injector having such a structure, when the two dollar valve 4 is opened, fuel is injected from the annular gap around the bottle part 3 as a spray. Then, the spray stream flows through the third jet passage 5 of the adapter 8 along the convex portions 9a and 9b.
The spray is branched as shown by arrows in the figure, and is ejected from the downstream end face of the adapter as a branched spray flow as shown by F in the figure.

At this time, since the spray flow smoothly flows along the convex portions 9a and 9b, there is little adhesion to the wall surface, and therefore the spray flow atomized in the bottle portion is flowed downstream in a good spray state.

The present invention can also be implemented in such a way that the number of convex portions is three or more to further divide the spray stream into multiple directions. For example, as shown in FIG.
° has a roughly triangular cross section, and the three convex portions 9°1, 9°b, and 9°C projecting from the center of each side substantially connect the downstream side of the jet passage 5 to a plurality of It is divided into branch jet flow passage parts.

In the above embodiments, the convex portion is formed by a radius, or the convex portion may be formed by an edge. In addition, although a bottle-type injection valve has been exemplified above, the present invention can also be applied to a ball-type injection valve as another embodiment.

(Effects of the Invention) Since the present invention is configured as described above, in a multi-directional injector equipped with an adapter, it is possible to reduce the adhesion of fuel particles to the wall surface when the spray stream is branched into multiple directions. Not only can the atomization performance be improved, but also a multi-directional injector with good atomization performance can be easily obtained by installing a simple single-hole adapter.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of the tip of a multidirectional injector according to an embodiment of the present invention, FIG. 2 is a sectional view taken along line A-A in FIG. 1, and FIG. 3 is an enlarged view of part B in FIG. 2. Perspective view, Fig. 4(a),
(b) and (c) are a top view showing the jet flow passage structure of the adapter in the same embodiment, its b-b cross-sectional view, and c
-c sectional view, FIG. 5 is a top view showing the jet flow passage structure of another embodiment of the present invention, FIG. 6 is a longitudinal sectional view of the tip of a conventional multidirectional injector, and FIG. It is a bottom view of an injector. 1: fuel injection hole, 2. body, 3. Bottle part, 4, needle valve, 5/jet passage, 8.8' adapter, 9a
, 9b, 9c: convex portions.

Claims (3)

[Claims] (1) In a multi-directional injector that is equipped with a fuel injection hole and a valve that controls opening and closing of the fuel injection hole, and is also provided with an adapter that forms a branched injection passage downstream of the fuel injection hole, the adapter 1. A multi-directional injection type injector, characterized in that the jet passage is of a single-hole type, and the jet passage is substantially divided into a plurality of jet passage parts on the downstream side by a convex portion formed protruding from a side surface. (2) The multidirectional injector according to claim 1, wherein a plurality of convex portions are protruded from the side surface of the injection passage of the adapter, and the number and branching angle of the jet flow are set by the plurality of convex portions. (3) The diameter D of the circle inscribed in the top of the convex portion centered on the valve axis at the most downstream end face of the adapter is 0.
Claim 1 or 2 formed so that <D≦1.5 mm.
The multidirectional injector described.