JP2002195134A - Fuel injection valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide spray of asymmetrical sprayed fuel flow distribution in a suction stroke injection for homogeneous combustion of a cylinder fuel injection engine for improving concentration homogeneity of air fuel mixture. SOLUTION: Walls 204a, 204b, 205a, 205b parallel to a center axis are provided at an injection hole outlet part, and several areas restricting a motion of fuel in an injection hole radius direction and areas not restricting the motion are provided around the injection hole. Also, area not restricting the motion have different sizes each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a fuel injection valve used in an internal combustion engine.

[0002]

2. Description of the Related Art As disclosed in Japanese Patent Application Laid-Open No. H11-159421, a fuel injection valve used in a direct injection type engine has a fuel injection port whose outlet periphery is not perpendicular to the fuel injection valve main body axis. The restraining force that restrains the fuel in the radial direction of the injection hole changes in the circumferential direction, and the reach of the spray injected from the peripheral edge of the injection hole with a small restraining force is large, 2. Description of the Related Art There is a fuel injection valve that reduces the reach of spray injected from a peripheral portion of an injection hole, stably supplies the spray toward a spark plug, and improves stability during stratified combustion.

[0003]

In fuel injection for homogeneous combustion, it is important that the injected fuel is sufficiently mixed with air during the period before ignition. For this reason, it is necessary to be able to adjust the distribution of the flow rate of the fuel that goes to the ignition plug side of the combustion chamber and the fuel that goes to the piston side among the injected fuel.

[0004] However, the fuel injection valve in the prior art increases the stability of combustion by making it easier for the fuel to reach the spark plug mainly during stratified charge combustion. There is no disclosure of a fuel injection valve in which the flow distribution of the fuel is different between the fuel spray toward the piston and the fuel spray toward the spark plug.

An object of the present invention has been made in view of the above-mentioned problems, and promotes mixing of spray fuel with air.
An object of the present invention is to provide a fuel injection valve capable of forming sprays having different flow distributions in order to improve combustion stability during homogeneous combustion.

[0006]

The fuel injection valve further includes, at a position downstream of the injection hole and outside the injection hole, a travel restraint means for restraining the progress of the fuel. By restricting the progress and dividing the injected fuel spray into a dense part and a thin part, and by making the amounts of the divided fuel spray dense parts different, respectively, the piston side and the spark plug side It is possible to make the distribution of the flow rate of the fuel toward the fuel cell different.

The advance restraint means may be provided with a wall which restrains the fuel from moving in the radial direction substantially parallel to the injection hole, or at a center axis of the injection hole which limits the progress of the injected fuel. A plurality of substantially parallel wall surfaces are provided. With such a wall surface, a plurality of restraint ranges in which the movement of the fuel in the radial direction or the traveling direction is restrained and a plurality of open ranges in which the fuel can move in the radial direction can be respectively generated.

By making the ranges of the plurality of open ranges different from each other, in a fuel injection valve used in a direct injection internal combustion engine having an injection hole for injecting fuel, the fuel spray injected from the injection hole is The concentration distribution in a cross section perpendicular to the main body axis of the fuel injection valve is concentrated in substantially two directions, and it is possible to set the spray shape such that one of the concentrated sprays has a large flow rate and the other has a small flow rate. it can.

As a result, according to the fuel injection valve of the present invention,
It is possible to form a spray having an asymmetric concentration distribution with respect to the injection hole axis. When the fuel injection valve is used in a direct injection type internal combustion engine, the flow rate of the fuel in the direction of the spark plug and in the direction of the piston It will be possible to provide a fuel injector whose distribution is suitable for mixing fuel and air.

[0010]

FIG. 1 is a sectional view showing the structure of one embodiment of a fuel injection valve according to the present invention. The fuel injection valve shown in FIG. 1 is a normally closed electromagnetic fuel injection valve,
When the coil 109 is not energized, the valve body 102 and the seat portion 202 are in close contact with each other. The fuel is supplied from a fuel supply port in a state where pressure is applied by a fuel pump (not shown), and the fuel passage 106 of the fuel injection valve is filled with the fuel until the valve body 102 and the seat portion 202 come into close contact with each other. When the coil 109 is energized and the valve body 102 moves away from the seat, fuel is injected from the injection hole 101.
Here, the fuel reaches the injection hole 101 through the swirl groove provided in the swirl element 107, but when passing through the swirl groove of the swirl element 107, the fuel is given a swirling force, and the fuel swirls from the injection hole 101. It squirts while squirting.

FIG. 2 is an enlarged sectional view showing the vicinity of the injection hole opening of the fuel injection valve shown in FIG. 1, and FIG. 3 is a front view seen from the direction of arrow III in FIG. In addition, FIG.
This corresponds to a sectional view taken along the line I-II. Also, FIG.
Axial direction of fuel injection valve (direction along valve axis)
The injection hole center axis 200a is shown by a dashed line. The direction of the injection hole center axis 200a coincides with the driving direction of the valve body 102. In FIG. 3, a line segment 200b passing through the center of the injection hole 101 and orthogonal to the injection hole central axis 200a and a line segment 200c passing through the center of the injection hole 101 and orthogonal to the injection hole central axis 200a and the line segment 200b are indicated by one point. This is indicated by a chain line.

The injection hole center axis 20 on the opening end side of the injection hole 101
A recess 203 is provided on a surface perpendicular to 0 a so as to cover the opening of the injection hole 101. Due to the recess 203, the wall surface 2 parallel to the injection hole center axis 200a is formed at the injection hole opening.
04a, 204b, 205a, and 205b are formed. The distance between the wall surface 204a and the wall surface 205a is the wall surface 2
It is provided to be smaller than the distance between the wall 04b and the wall surface 205b.

FIG. 4 is a further enlarged view of the injection hole opening shown in FIG. 3, showing the state of fuel injected from the injection hole.
It is a figure near 01. Of the figure, portions that are shaded are part which is relatively convex with respect to the recess 203.

The wall in the range indicated by points 405 to 406 and the wall in the range indicated by points 407 to 404 are:
It is provided outside the nozzle hole inner wall 201 in the nozzle hole radial direction. By doing so, when machining the nozzle hole opening,
After processing and forming a wall surface parallel to the injection hole center axis 200a and downstream of the injection hole, when drilling the injection hole 101 from the upstream side of the injection hole with a punch or the like, the points 405 to 40
6 and the inner wall of the injection hole can be machined by applying a member between the wall surface in the range indicated by reference numeral 6 and the wall surface in the range indicated by points 407 to 404, and precise processing of the opening end of the injection hole is easy. Become.

The fuel injection valve shown in FIGS. 1 to 4 is provided at points 405 to 406 as means for restraining the fuel from moving in the radial direction downstream and outside the injection hole of the spiral-type fuel injection valve.
And a wall surface parallel to the injection hole center axis 200a, which is indicated by a range from point 407 to point 404.

The fuel injection valve shown in FIGS. 1 to 4 is a spiral fuel injection valve, and fuel is injected from an injection hole 101 while turning. In the vicinity of the center of the injection hole 101, the fuel turns to a low pressure due to the swirling, and the fuel turns into a film while turning, and flows down along the injection hole wall surface 201.
Therefore, the fuel is injected from the outer periphery of the nozzle hole inner wall 201 with a speed of a component in a tangential direction (that is, a component in a turning direction) and a speed of a component in a downstream direction of the nozzle hole center axis 200. The arrow 403 shown in FIG.
Reference numerals 408 to 412 indicate the fuel injection directions.

Of the wall surfaces parallel to the injection hole center axis 200a, the range from the point 405 to the point 406 and the range from the point 407 to the point 404 are constrained wall surfaces for restricting the radial movement of the fuel injection hole. . On this constrained wall surface, the fuel continues the swirling motion, so that the fuel injection amount is smaller than the range in which the fuel injection hole is not constrained to move in the radial direction. In particular, if the height of the wall is high enough, the fuel
Almost no injection is made from the range from 5 to 406 and from the range from 407 to 404.

The amount of fuel injected from the constraining wall surface is determined by the ratio of the speed of the fuel in the turning direction to the speed in the direction of the central axis of the injection hole, and the height of the constraining wall surface. For example, if the height of the restraint wall is higher than the length of the fuel moving in the direction of the injection hole center axis while the fuel is swirling in the range from the point 405 to the point 406, the fuel moves from the range from the point 405 to the point 406. Is hardly injected.

On the other hand, between point 404 and point 405, and point 4
In the range between 06 and point 407, most of the fuel is injected from these ranges since the fuel is not restrained from moving in the orifice radial direction.

The spread of the fuel spray after injection is substantially determined by the size of the open area where the movement of these fuels in the radial direction of the injection hole is not restricted.
By changing the ratio between the size of the range between and the size of the range between the points 406 and 407, the ratio of the flow rate of the fuel ejected from each range can be adjusted.

Here, in order to form a uniform spray of the fuel injected from the open range, the positional relationship between the points 406 and 407 which determine the open range on the side where a large flow rate is injected is determined by the injection The angle passing through the open range from the point 406 to the point 407 around the hole center axis 200a is 180 degrees,
Desirably larger. This corresponds to points 405 and 40, which are the ranges that restrict the movement of the fuel in the radial direction of the injection hole.
6, and the distance between points 407 and 404 is large, the amount of fuel that swirls along these walls and flows out increases, and these fuels start at point 40, the beginning of the open range.
6 and the point 404, the concentration of the fuel flowing out of these points becomes high, so that the concentration distribution of the spray tends to be non-uniform.

The positional relationship between the point 406 and the point 407 which determine the open range on the side where a large flow rate is injected is determined by the injection hole center axis 20.
When the angle passing through the open range from the point 406 to the point 407 around the point 0a is 180 degrees or more, the circumferential length of the wall that restrains the fuel from moving in the radial direction of the injection hole is reduced, The amount of fuel flowing out from the start points 404 and 406 of the open range can be suppressed, and the fuel spray injected from the open range can be made uniform.

As mentioned above, points 406 and 404
It is known that the fuel injected from the nozzle has a function of increasing the concentration of the spray, and in this portion, the reach of the spray after the injection becomes long. When the spray distance is particularly required depending on the engine, it is possible to intentionally create such a concentrated region of the spray and partially lengthen the spray distance. In this case, the range between the points 405 and 406, which are the ranges for restraining the fuel from moving in the radial direction, and the point 4
It is preferable to lengthen the range from 07 to the point 404 or increase the height of the wall surface in this range.

In the fuel injection valve shown in FIGS. 1 to 4, as described above, the uniformity of the fuel spray can be changed by the size of the range in which the movement of the fuel in the radial direction is released. For example, when it is desired that the fuel is uniform, the fuel spray is divided into substantially two directions using a structure as shown in FIG. Each spray can be made uniform.

FIG. 5 shows a wall 501 and a wall 50 substantially parallel to the central axis 200a of the injection hole as fuel progress restraining means.
FIG. 2 is an example in which No. 2 is provided on the downstream side and outside of the injection hole, and is a front view seen from the downstream side of the injection hole. Walls 501 and 502
Is provided at a position where it comes into contact with fuel after the fuel flowing down along the injection hole inner wall 201 is injected.

The distance Cw between the inner wall 201 of the injection hole and the wall 501 such that the injected fuel comes into contact with the wall 501 is:
The velocity Vt in the fuel swirling direction and the velocity Va in the direction of the injection hole center axis.
And the height Hw of the restraint wall determine the maximum value. That is, Cw is at least Hw · Vt / V
It must be smaller than a. The value of the ratio Vt / Va of the velocity Vt in the fuel swirling direction to the velocity Va in the direction of the central axis of the injection hole can be estimated from the spread angle θ of the fuel spray, and the relationship is tan θ = Vt / Va.

Here, the spread angle θ of the fuel spray is shown in FIG.
As shown in the figure, the fuel injected from the injection hole is
It is the angle θ when spreading in the direction away from 00a. FIG. 12 is a cross-sectional view showing the state of the fuel injected from the injection hole opening of the fuel injection valve shown in FIG. 5 along the line IV-IV. Actually, a cross-section of the fuel spray is photographed as shown in FIG. 12 by irradiating the fuel spray with sheet-like light (such as a laser beam) passing through the central axis 200a of the injection hole. Then, the spread angle θ of the fuel spray can be measured.

In the fuel injection valve shown in FIG. 5, the fuel flowing down while turning along the inner wall 201 of the injection hole is injected in the directions of arrows 511 to 516 at the opening end of the injection hole.
At this time, a part of the wall surface 501 and a part of the wall surface 502 which is the fuel restraining means interferes with the injected fuel, and the fuel does not fly in the original direction.

For example, in FIG. 5, the fuel injected in the direction of the arrow 511 flies without interference between the fuel and the wall surface 502 because the distance L between the injection point 511a of the arrow 511 and the wall surface 502 is long. On the other hand, the fuel injected in the directions of arrows 512 and 513 interferes with the wall surface 502 due to the short distance between the injection point 512a and the injection point 513a and the wall surface 502, and does not fly in the original direction.

Similarly, the fuel in the direction indicated by the arrow 515 interferes with the wall surface 501 and does not fly in the original direction.

As described above, the interference between the fuel and the wall surface occurs due to the wall surface 501 and the wall surface 502 provided as the fuel traveling restraining means. As a result, the distribution of the spray as shown in FIG. 6 can be obtained.

Further, in order to obtain the same effect as in FIG. 5, the shape of the injection hole opening as shown in FIG. 11 may be used. In FIG. 11, as means for restraining the progress of fuel after injection,
It has a wall surface 501 'and a wall surface 502' parallel to the central axis of the injection hole. Here, the restricted range in which the progress of the fuel is restricted and the open range in which the progress of the fuel is not restricted are defined by the inner wall 2 of the injection hole.
It can be adjusted according to the positional relationship between 01, wall surface 501 'and wall surface 502'.

The open ranges α and β of the fuel in FIG.
The distance L from the fuel injection point, the height Hw of the wall surfaces 501 ′ and 502 ′, and the velocity component V in the fuel turning direction
t and the velocity component Va in the direction of the central axis of the injection hole.

In FIG. 11, the injection point 1102 on the inner wall 201 of the injection hole is exactly at the boundary between the open range and the restricted range, and the fuel injected from the injection point on the range β side from this is the wall surface 502 '. And no longer interfere. Injection point 110
Similarly, the fuel injected from the injection point on the range α side is located on the wall surface 501 ′.
And no longer interfere.

At the injection point at such a boundary,
The positional relationship between the wall surface and the injection point is represented by a distance L from the fuel injection point.
And the height Hw of the wall surfaces 501 'and 502', the velocity component Vt in the fuel swirling direction, and the velocity component Va in the direction of the injection hole central axis, and the relationship is L = Hw × Vt /
Va.

On the other hand, the injection points 1103 and 11
04 is also a point on the boundary between the open range and the restricted range. The injection point serving as such a boundary is located at the position of the wall surface 501a and the wall surface 502a that is closest to the inner wall of the injection hole (points 1107 and 1108 in FIG. 11).
Therefore, the contact point is obtained when a tangent is drawn to the injection hole inner wall 201.

As described above, the four boundaries between the open range and the restricted range correspond to the wall surfaces 501 'and 502' and the injection hole inner wall 20.
1 and the height of the wall surface 501 'and the wall surface 502' can be adjusted. As a result, the size of each of the open range and the constraint range can be adjusted. For example, increasing the height of the wall surfaces 501 'and 502' narrows the open range. Also, the wall 50
When the 1 ′ and the wall surface 502 ′ are installed away from the inner wall of the injection hole, the open range becomes wider.

FIG. 6 shows the injection hole center axis 200a in FIG.
Wall surfaces 205b, 205a, 204a and 204b parallel to
FIG. 5 is a view of an opening of a fuel injection valve in which a part of the fuel injection valve is configured to be in contact with an inner wall of the injection hole to form a part of the inner wall of the injection hole. That is,
In FIG. 6, the injection hole center axis 200 of the injection hole inner wall 201 'is shown.
The length in the a direction is different from the circumferential direction of the injection hole. In the range from the point 601 to the point 602 and the range from the point 603 to the point 604, the length of the inner wall of the injection hole is increased in the direction of the injection hole center axis 200a (that is, the depth direction with respect to the paper surface of FIG. 6), It has a function as a means for restraining the fuel from moving in the radial direction. On the other hand, point 601
In the range from the point 603 to the point 603 and the range from the point 602 to the point 604, the length of the injection hole inner wall 201 ′ is
It is shorter in the direction of 0a, and is an open range that does not restrict the movement of the fuel in the radial direction.

Here, from the point 601 to the point 6 which is the open range,
The range of 03 and the range of points 602 to 604 are different from each other. That is, a plurality of ranges of the inner peripheral wall 201 ′ of the injection hole inner wall 201 ′ having a short length in the direction of the injection hole central axis 200 a are provided in the circumferential direction of the injection hole.
The portions in the circumferential direction of the portions having shorter lengths in the direction are different from each other.

Even when the fuel injection valve having the structure as shown in FIG. 6 is used, the same effect as when the fuel injection valve having the shape of the injection hole opening shown in FIG. 3 is used can be obtained. In such a configuration, a general fuel injection valve having no wall surface parallel to the injection hole central axis 200a at the injection hole opening is easily cut or plastically processed in a near-net shape by performing processing shown in FIG. The shape of the injection hole opening as described above can be obtained.

FIG. 7 is a diagram schematically showing the shape of the spray formed by the fuel injected by the fuel injection valve exemplified in FIGS. The figure is a view from the downstream side of the fuel injection valve, and the shape of the spray shows a cross section in a plane perpendicular to the central axis of the injection hole.

Each of the fuel injection valves shown in FIGS. 1 to 6 has fuel advance restraint means, and the travel restraint means restrains the progress of the fuel in at least two places, and the range over which the progress of the fuel is restrained is limited. By being different at each location, the distribution shape of the spray in the cross section perpendicular to the injection hole center axis 200a is as follows:
As shown in FIG. 7, the spray is divided into substantially two directions 701 and 702, and the distribution and the spread of each spray are different.

The distribution shape of the spray can be changed by the size of the open range that does not restrict the progress of the fuel.

Specifically, in the fuel injection valve shown in FIG. 4, the height Hw of the wall surface parallel to the injection hole center axis 200a.
(Shown in FIG. 2) and respective widths (Wa and W in FIG. 4)
It can be changed by changing b). For example, when the height Hw of the wall surface is increased, the effect of the wall surface that restrains the fuel from moving in the radial direction with respect to the swirling fuel increases, and the spread of the spray becomes narrow. Further, by changing Wa and Wb, it is possible to change the width of the open area that does not restrict the movement of the fuel in the radial direction, and to distribute the flow rate of the spray divided in substantially two directions in each direction. Can be adjusted.

FIG. 8 shows a fuel injection valve having an injection hole opening shown in FIGS. 1 to 5 attached to an intake valve side of a two-intake, two-exhaust, two-valve, direct injection engine. FIG. 4 is a cross-sectional view illustrating a state inside the engine cylinder when fuel is injected into the engine cylinder. Since the injection is performed during the intake stroke, the intake valve 803 is open during fuel injection. It is preferable that the fuel injection valve be installed such that the side with the lower flow rate is directed toward the ignition plug 802 and the side with the higher flow rate is directed toward the piston 804 in the spray flow concentration portion where the flow rate of the fuel is concentrated in substantially two directions.

When fuel is injected with this type of attachment, there is a spray toward the piston 804 below the intake valve 803 and a spray toward the upper direction of the intake valve 803, so that the mixture in the cylinder at the time of ignition is mixed. If the fuel concentration distribution in the air is too lean near the spark plug 802 or the piston 8
It is possible to prevent the fuel concentration distribution on the 04 side from being excessively rich. Lean or excessive fuel concentration near the spark plug 802 is one of the causes of misfire that does not ignite the air-fuel mixture. This has the effect of preventing the output of the engine and reducing the emission of unburned fuel.

The effect as described above is obtained by providing the fuel advance restraint means downstream of the injection hole, and is not limited to the shape of the injection hole opening illustrated in FIGS. 3, 4, and 5. . For example, a fuel injection valve having an injection hole opening shape as shown in FIGS. 9 and 10 can be obtained. Even in the shape of the injection hole opening shown in FIGS. 9 and 10, two movements in the injection hole circumferential direction in which the movement of the fuel in the injection hole radial direction is not restricted are provided downstream from the injection hole opening end. And the sizes of the ranges are different from each other. With such a configuration, the distribution of the spray in the cross section perpendicular to the injection hole axis 200a of the injected spray is concentrated in approximately two directions, and one of the concentrated sprays has a large flow rate and the other has a small flow rate. The spray shape can be set as follows.

The shape of the injection hole opening shown in FIGS. 9 and 10 is generated when fuel and lubricating oil are carbonized when the fuel injection valve is mounted on a direct injection engine and used. There is also an effect of reducing changes in the fuel injection direction and the spray concentration due to the deposits.

FIG. 10 is a further enlarged view of the injection hole opening shown in FIG. 9. In the injection hole opening, the recess wall surface 205 b ″ on the upstream side with respect to the fuel movement (swirl) direction and The appearance of the deposits 903 and 904 deposited on 205a ″ is also shown.

In the shape of the injection hole opening shown in FIG. 9, the angle formed by the corner portion 1005 connecting the upstream concave wall surface 205b "with the wall surface 204b" is an acute angle.
The angle formed by the corner portion 906 connected to the wall surface 05b ″ and the wall surface 204a ″ is substantially a right angle. Wall surface 2 connected to corner 905
05a "and the wall surface 205b" connected to the corner 906 are:
Both are located at positions where they do not interfere with the injected fuel, but deposits tend to accumulate on such walls when the engine is operated. In the case of the injection hole opening shown in FIG.
5b and wall surface 205a correspond to wall surface 205b "and wall surface 205a" in FIG. 10, respectively. In the case of the nozzle hole opening shown in FIG. 4, when the deposit adheres to the wall surface 205b and the wall surface 205a, the deposit is deposited on the wall surface 205b.
In addition, the sediment tends to interfere with the injected fuel because the sediment grows and grows in a direction substantially perpendicular to the wall surface 205a. Therefore, as shown in FIG.
a ", and the wall 205a" and the wall 204
When the angle formed with b ″ is substantially a right angle or an acute angle, the deposits deposited on the wall surfaces 205b ″ and 205a ″ are less likely to interfere with the flying fuel. Thus, the change in the shape of the spray can be suppressed.

Further, the shape of the injection hole opening shown in FIGS. 9 and 10 is devised so that a desired spray shape can be obtained even when the shape of the opening is formed by plastic working. In the shape of the injection hole opening shown in FIGS. 9 and 10, the wall surface 20 on the downstream side with respect to the movement (swirl direction) of the fuel is provided.
4 a ″ and the wall surface 204 b ″ are formed at a position closest to the nozzle hole inner wall surface 201 in a direction substantially tangential to the circumference of the nozzle hole inner wall surface 201.

The wall surfaces 204a "and 204b" on the downstream side in the turning direction in FIG. 10 correspond to the wall surfaces 204a and 204b in FIG. 4, respectively. At the position closest to the inner wall surface 201 of the hole, it is not formed in a direction substantially tangential to the circumference of the inner wall surface 201 of the injection hole, and has an angle.

In general, when forming the injection hole opening by plastic working, it is not easy to work the corners, but it is easier to provide an R portion having a curvature. However, the wall 20
In the wall surface which interferes with the fuel flying and influences the shape of the spray as shown in 4a, the distance from the fuel injection position on the outer periphery of the injection hole inner wall 201 changes depending on the R portion, so that the flight depends on the size of the R portion. The degree of interference with the burning fuel is different. For this reason, the shape of the spray may vary from one manufactured fuel injection valve to another due to a manufacturing dimensional difference of the R portion.

Therefore, as shown in FIG.
Since the a ″ and the wall surface 204b ″ are formed in a position substantially closest to the inner wall surface 201 of the injection hole and in a direction substantially tangential to the circumference of the inner wall surface 201 of the injection hole, they interfere with the fuel to fly and form a spray. It is no longer necessary to provide corners on the affected wall surface, and even if the injection hole opening is machined by a machining method that makes it easier to make the corners with curvature such as plastic working, the fuel that produces the desired spray shape can be obtained. An injection valve can be obtained.

As described above, according to the present invention, the injection hole opening of the spiral fuel injection valve having a single injection hole is processed so as to cover the circumferential area of the injection hole opening. By providing a plurality of open ranges in which the fuel can be moved in the radial direction and making the sizes of the open ranges different from each other, the flow rate of the spray is concentrated in substantially two directions by a relatively easy method. A fuel injection valve having a different flow distribution can be provided. These effects are obtained by changing the shape of the injection hole opening, and there is no need to add new components.Therefore, a fuel injection valve suitable for a direct injection engine can be provided without significantly increasing costs. Can be provided.

[0056]

According to the fuel injection valve of the present invention, it is possible to obtain a spray having a desired shape for a direct injection engine.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an example of a fuel injection valve according to the present invention.

FIG. 2 is an enlarged sectional view of the vicinity of an injection hole of a fuel injection valve according to the present invention.

FIG. 3 is a front view of the vicinity of the injection hole of the fuel injection valve when FIG. 2 is viewed in the direction of arrow III.

FIG. 4 is a front view in which the vicinity of the injection hole shown in FIG. 3 is further enlarged (shading indicates a convex portion in the front direction on the paper).

FIG. 5 is an enlarged view of the vicinity of the injection hole of a fuel injection valve provided with a wall for restraining the progress of fuel as an example of the fuel injection valve according to the present invention. (The shaded area indicates a convex portion toward the front of the paper.)

6 is an enlarged view of the vicinity of the injection hole, showing an example in which a means for restricting movement of fuel in the radial direction of the fuel injection valve shown in FIG. 4 is provided as an extension of the injection hole. (The shaded area indicates a convex portion toward the front of the paper.)

FIG. 7 is a cross-sectional view schematically showing a shape of a spray obtained by the fuel injection valve of the present invention.

FIG. 8 is a sectional view showing an example in which the fuel injection valve according to the present invention is mounted on an internal combustion engine.

FIG. 9 is a sectional view and a front view showing an example of a fuel injection valve according to the present invention.

FIG. 10 is a further enlarged view of the vicinity of the injection hole of the fuel injection valve shown in FIG.

FIG. 11 is an enlarged front view of the vicinity of the injection hole, showing an embodiment of a fuel injection valve having the same function as the fuel injection valve shown in FIG. (The shaded area indicates a convex portion toward the front of the paper.)

FIG. 12 is a cross-sectional view showing a state of fuel spray.

[Explanation of symbols]

101: injection hole, 102: valve element, 103: nozzle part, 10
4 core, 106 fuel passage, 107 swivel element, 10
8: spring, 109: coil, 200a: central hole of injection hole, 201: inner wall of injection hole, 202: seat portion, 203: concave portion, 204a, 204a ′, 204a ″: wall surface (downstream turning side), 204b, 204b ′, 204b "... wall surface (turning downstream side), 205a, 205a ', 205a" ... wall surface (turning upstream side), 205b, 205b', 205b "...
Wall surface (upstream side of swirl), 211 ... fuel swirl direction, 403
… Fuel swirling direction, 404… point on the wall surface, 405… point on the wall surface, 406… point on the wall surface, 407… point on the wall surface, 4
08: fuel injection direction, 409: fuel injection direction, 41
0: fuel injection direction, 411: fuel injection direction, 412
... Fuel injection direction, 501,502 ... Progress restraint wall surface, 5
03,504: convex portion, 511, 512, 513, 51
4,515,516 ... fuel injection direction, 511a, 51
2a, 513a: fuel injection points, 601, 602, 60
3, 604: points on the wall surface, 701, 702: outer shape of fuel spray, 801: fuel injection valve, 802: spark plug, 80
3a: intake valve, 803b: intake valve, 804: piston,
805: exhaust valve, 806: cylinder wall, 807: spray
903: bottom of concave portion, 908: turning direction of fuel, 901,
902: fuel injection direction, 1003, 1004: sediment, 1101, 1102, 1103, 1104: fuel injection point, 1105, 1106: interference position between wall surface and Nenryo, 1107, 1108: points on wall surface

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yuzo Kadokomu 502 Kandate-cho, Tsuchiura-city, Ibaraki Pref. Machinery Research Laboratories, Hitachi, Ltd. Inside Machinery Research Laboratory (72) Inventor Ayumu Miyajima 502 Kandachicho, Tsuchiura-shi, Ibaraki Prefecture Inside Machinery Research Laboratories, Hitachi Ltd. Within the group (72) Inventor Yasuo Ikuizawa 2520, Odaiba, Hitachinaka-shi, Ibaraki F-term within the automotive equipment group of Hitachi, Ltd. (Reference) 3G066 AA02 AB02 AD12 BA02 BA32 BA55 BA61 CC05U CC14 CC21 CC37 CC41 CC48 DB00

Claims (7)

[Claims] An injection hole for injecting fuel is provided, a valve seat is provided upstream of the injection hole, a valve body for opening and closing a fuel passage between the valve seat and a driving means for driving the valve body. In the fuel injection valve provided, the fuel injection valve further comprises a progress restraint means for restraining the progress of the fuel on the downstream side of the injection hole and outside the injection hole, and the progress restraint means restrains the progress of the fuel at at least two points. A fuel injection valve, wherein the injected fuel spray is divided into a high density portion and a low density portion, and the amount of the split high density portion is different from each other. 2. The fuel injection valve according to claim 1, wherein a wall for restraining the fuel from moving in a radial direction is provided downstream of the injection hole as the advancement restraining means so as to be along the injection hole. A plurality of restraint ranges in which fuel is restrained from moving in the radial direction, and a plurality of open ranges in which fuel can move in the radial direction, wherein the sizes of the open ranges are different from each other. And the fuel injection valve. 3. The fuel injection valve according to claim 1, wherein a plurality of wall surfaces substantially parallel to a central axis of the injection hole for restricting the progress of the injected fuel are provided as the progress restricting means, A fuel injection valve characterized in that a plurality of restriction ranges for restricting the movement of the fuel injection valve and a plurality of open ranges where the fuel can move in the traveling direction are provided, and the sizes of the open ranges are different from each other. . 4. An injection hole for injecting fuel, a valve seat upstream of the injection hole, a valve element for opening and closing a fuel passage between the valve seat, and a valve element driven by driving the valve element. In the fuel injection valve provided with a driving means for driving the injection hole, a wall surface substantially parallel to a central axis of the injection hole is provided on a peripheral edge of the injection hole downstream of the injection hole at a predetermined distance from an inner wall of the injection hole. A plurality of circumferential ranges of the inner wall of the injection hole such that a distance between the wall surface and the inner wall of the injection hole is longer than a predetermined distance, and a fuel provided so that the sizes of the circumferential ranges are different from each other. Injection valve. 5. The fuel injection valve according to claim 1, wherein the fuel spray injected from the injection hole has a concentration distribution in a cross section perpendicular to the main body axis of the fuel injection valve. A fuel injection valve characterized by being set in a spray shape that is concentrated in two directions and one of the concentrated sprays has a larger flow rate and the other has a smaller flow rate. 6. The fuel injection valve according to claim 2, wherein at least one wall surface parallel to the central axis of the injection hole is provided downstream of the injection hole, and at least one of the wall surfaces is provided. A fuel injection valve, wherein a relationship between one wall surface and an inner wall of the injection hole at a position closest to the wall surface and the wall surface is a relationship of a substantially contact angle. 7. The fuel injection valve according to claim 2, wherein at least one wall surface parallel to a central axis of the injection hole is provided downstream of the injection hole, and at least one of the wall surfaces is provided. A fuel injection valve, comprising: a wall surface such that a relationship between an inner wall of the injection hole at a position closest to the wall surface and the wall surface is substantially a right angle or an acute angle.