JP2855360B2 - Multi-directional injector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an injector used for a multi-valve internal combustion engine having a plurality of intake valves, and more particularly to a multi-valve type in which a jet branch adapter is attached to an electromagnetic injection valve. The present invention relates to a directional injector.

(Prior art) As an injector for injecting fuel into an engine or the like,
A jet branch using a pintle type injection valve having a fuel injection hole and a needle valve inserted through the fuel injection hole, and further having a jet passage downstream of the injection hole, the downstream side of which is divided into a plurality of branch holes. 2. Description of the Related Art A multi-directional injector equipped with a mold adapter has been conventionally known.

In this conventional injector, when the needle valve is opened, fuel is sprayed and injected from an annular gap around a pintle provided at the tip of the needle valve. The spray flow impinges on the branch portion of the adapter and splits in a plurality of directions, flows downstream of each branch hole, and fuel is injected into a plurality of intake valves. However, in the injector having such a structure, the spray flow atomized by the pintle portion collides with the branch portion and flows along the wall surface. There is a problem that it cannot flow into the combustion chamber as it is.

Therefore, the present applicant has made the spray passage of the adapter a single hole type, abolished the branch portion on the valve axis, and divided the jet flow passage into a plurality of branch holes substantially on the downstream side by a convex portion protruding from the side surface. A multi-directional injector has been proposed. FIG. 7 shows an adapter 1 in the injector.
Is provided at the tip of a sleeve-shaped body (not shown) having a fuel injection hole so as to form a single-hole type jet passage for branching the spray flow in two directions. Are substantially elliptical, and a pair of convex portions 3 (only one side is shown in the figure) from both side surfaces on the short axis side toward the center.
Are protrudingly formed and are divided into branch hole portions 2a and 2b that substantially form two branch holes on the downstream side. In the injector having such a structure, the spray flow injected from the annular gap around the pintle portion is branched in the jet flow path of the adapter 1 along the convex portion 3 as shown by an arrow,
It is ejected from the downstream end face of the adapter as a branch spray flow.

(Problem to be Solved by the Invention) By making the injector as described above, the spray flow can be divided into a plurality of directions and flow downstream while maintaining the atomization state. However, in such an injector, the branch holes 2a and 2b of the jet passage are formed symmetrically with respect to the convex portion 3, and the pair of convex portions 3 are symmetrical with respect to the center line B of the fuel injection hole. Since it is arranged at a position, the fuel is supplied evenly to the plurality of intake ports, so that there is a problem that the fuel cannot be supplied according to the combustion conditions in the cylinder.

The present invention has been made in view of the above problems,
It is an object of the present invention to provide a multidirectional injector in which fuel is supplied in accordance with combustion conditions in a cylinder to improve combustion efficiency and fuel efficiency.

(Means for Solving the Problems) A multidirectional injector according to the present invention includes a fuel injection hole and a valve for controlling the opening and closing of the fuel injection hole, and forms a branched jet passage downstream of the fuel injection hole. In the multi-directional injection type injector provided with an adapter to be provided, the jet passage of the adapter is made a single hole type, and the jet passage is divided into a plurality of branch holes substantially on the downstream side by a convex portion protruding from a side surface. In addition, the convex portion is arranged so as to be shifted from the center line of the fuel injection hole, and this configuration makes it possible to change the flow ratio of the spray flow to each branch hole, Was solved.

The flow rate ratio can be changed by setting the diameter of each of the plurality of branch holes in accordance with the injection flow rate ratio.

Further, the number of branch holes may be set according to the injection flow ratio.

(Operation) The spray flow is branched into a plurality of branch holes by the convex portions formed in the adapter, and the flow rate ratio of the spray flow supplied to each branch hole is changed. Therefore, for example, the flow rate ratio can be set according to the combustion conditions in the cylinder, such as increasing the fuel concentration on the side of the ignition plug in the cylinder of the three-valve engine. Efficiency can be improved.

(Example) Hereinafter, an example is described based on drawings.

FIG. 1 is a longitudinal sectional view and a sectional view taken along line AA of the tip of a multidirectional injector according to an embodiment of the present invention, and FIG. 2 is an enlarged perspective view of a portion E in FIG.

This embodiment is applied to a three-valve engine. The multi-directional injector 4 includes a sleeve-shaped body 6 having a fuel injection hole 5 at the center of the end. A needle valve 8 having a pintle portion 7 is slidably mounted so that the pintle portion 7 projects into the fuel injection hole 5 of the body 6.

At the tip of the body 6, an adapter 1 is provided which forms a single-hole type jet flow path 2 for branching the spray flow in two directions downstream of the fuel injection hole 5. The jet passage 2 of the adapter 1 has a substantially elliptical cross section,
A pair of convex portions 3, 3 each having a tip formed by a radius from both side surfaces on the short axis side toward the center are formed to protrude,
On the left and right sides of the convex portions 3, 3, branch hole portions 2a, 2b forming substantially the same type of branch hole are formed.

In the injector 4 having such a structure, the spray flow injected from the annular gap around the pintle portion 7 flows along the convex portions 3, 3 in the jet passage 2 of the adapter 1 as shown by arrows in FIG. And is sprayed from the most downstream end face of the adapter as a branch spray flow through each of the branch holes 2a and 2b.

Here, the central axis B of the jet passage defined by the central axis B of the fuel injection hole 5 and the pair of convex portions 3, 3 of the adapter 1.
Are arranged with an offset distance D from each other, whereby the flow ratio of the spray flows branched into the left and right branch holes 2a and 2b is changed. By changing the flow ratio of the spray flow supplied to each of the branch holes 2a and 2b in this manner, as shown in FIG. 3, two intake ports 9, 10 on the left and right and one exhaust port are provided.
In the three-valve engine provided with 11, the spray flow supplied to the intake port 10 on the ignition plug 12 side can be set to be larger than the spray flow supplied to the intake port 9 on the other side. This increases the fuel concentration on the ignition plug 12 side and improves the combustion propagation speed, so that the combustion efficiency can be improved and the fuel efficiency can be improved.

FIG. 5 shows the axial deviation distance D (mm) and the left and right branch holes 2a, 2
This shows the relationship between b and the flow rate ratio. According to this graph, for example, when it is desired to set the flow ratio of the branch spray flow to each of the branch holes 2a and 2b to 1: 2, the axis deviation distance D may be set to be less than 0.3 mm.

FIGS. 5 and 6 relate to another embodiment of the present invention, and show the shapes of the branch holes in the adapter 1 respectively.

In the embodiment of FIG. 5, the central axis B of the fuel injection hole 5 is
And the central axis C of the jet passage defined by the convex portions 3 ', 3' of the adapter 1 are arranged with an offset distance D therebetween, and the left and right branch holes 2'a, 2'b The diameter is varied according to the required flow ratio. In this manner, the injection directionality can be improved by reducing the diameter of the branch hole portion 2'b on the smaller flow rate ratio side.

In the embodiment shown in FIG. 6, similarly to the above, the center axis B of the fuel injection hole 5 and the center axis C of the jet passage defined by the convex portions 3 ", 3" of the adapter 1 are offset from each other. The arrangement is made with the distance D, and the number of branch holes is changed according to the required flow rate ratio. That is, two branch holes 2 ″ a,
2 "c, and one branch hole 2'b is provided in the small jet passage.
Is provided. In each of the figures, a portion surrounded by a dashed line indicates a region of the spray fuel.

In the embodiment shown in FIGS. 5 and 6, the center axis B of the fuel injection hole 5 and the center axis C of the jet passage defined by the convex portion of the adapter 1 have an offset distance D from each other. The two central axes B and C may not be coincident with each other.

(Effect of the Invention) Since the present invention is configured as described above, for example,
In a three-valve engine, fuel can be supplied in accordance with combustion conditions in the cylinder, such as increasing the fuel concentration on the ignition plug side in the cylinder, thereby improving the combustion propagation speed, improving the combustion efficiency, and improving fuel efficiency. Can be improved.

[Brief description of the drawings]

FIG. 1 is a vertical sectional view of a tip portion of a multi-directional injector according to one embodiment of the present invention and a sectional view taken along line AA of FIG.
FIG. 3 is an enlarged perspective view of a portion E in FIG. 1, FIG. 3 is an explanatory diagram schematically showing a state of fuel supply into the cylinder by the injector, and FIG. 4 is a diagram showing the axial misalignment distance and the flow rate ratio of each branch hole. 5 and 6 are sectional views showing the shape of a branch hole according to another embodiment, and FIG. 7 is a view similar to FIG. 2 of a conventional injector. 1: Adapter, 2: Jet passage, 2a, 2b; 2'a, 2'b; 2 "a, 2" b,
2 ″ c: branch hole portion, 3: convex shape portion, 4: injector, 5: fuel injection hole, 8: needle valve.

Continuation of the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F02M 51/06-51/08 F02M 61/18 F02M 69/00 F02M 69/04

Claims (3)

(57) [Claims] 1. A multi-directional injector comprising a fuel injection hole, a valve for controlling opening and closing of the fuel injection hole, and an adapter for forming a branched jet flow path downstream of the fuel injection hole. The jet passage of the adapter is a single hole type, and the jet passage is substantially divided into a plurality of branch holes on the downstream side by a convex portion formed so as to protrude from the side surface, and the convex portion is centered on the fuel injection hole. A multi-directional injection type injector, which is arranged so as to be displaced from the injector. 2. A multi-directional injector comprising a fuel injection hole, a valve for controlling the opening and closing of the fuel injection hole, and an adapter for forming a branched jet passage downstream of the fuel injection hole. The jet passage of the adapter is of a single-hole type, and the jet passage is substantially divided into a plurality of branch holes on the downstream side by a convex portion formed so as to protrude from the side surface, and the diameter of each of the plurality of branch holes is determined by the injection flow A multi-directional injection injector characterized by being set according to a ratio. 3. A multi-directional injector comprising a fuel injection hole and a valve for controlling the opening and closing of the fuel injection hole and an adapter for forming a branched jet flow path downstream of the fuel injection hole. The jet passage of the adapter is of a single hole type, and the jet passage is substantially divided into a plurality of branch holes on the downstream side by a convex portion formed to protrude from the side surface, and the number of the plurality of branch holes is set to the injection flow ratio. A multi-directional injection injector characterized in that the injector is set accordingly.