JP2002115625A - Fuel injection valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel injection valve capable of uniformly distributing a fuel along the inner wall of an injection opening or an injection path and injecting it into a combustion chamber in the form of a conical peripheral wall. SOLUTION: The fuel injection valve 1 comprises a valve closure 4 forming a seal seat together with a valve seat face 6 formed on a valve seat body 5 and a swirling device 34 arranged on the outflow side of the seal seat with at least one swirl path 35 and one injection path 7. The longitudinal axis 46 of at least one swirl path 35 formed in the swirling device 34 is directed at an angle δsmaller than 90 deg. relative to the longitudinal axis 38 of the injection path 7. The fuel passing through the fuel injection valve 1 moves on a spiral track along the inner wall 40 of the injection path 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel injection valve, and more particularly to a fuel injection valve for directly injecting fuel into a combustion chamber of an internal combustion engine, which is provided with a valve closing body. A seal seat is formed together with a valve seat surface formed on the seat body, and a swirl device having at least one swirl passage and an injection passage is disposed at an outlet side of the seal seat. About things.

[0002]

BACKGROUND OF THE INVENTION German Patent Publication No. 19815
The fuel injection valve known from U.S. Pat. No. 789 is characterized by the following configuration. That is, the known fuel injection valve has a swirl disk downstream of the valve seat, the swirl disk being made of at least one metallic material,
It has at least two swirl passages opening into the swirl chamber and in all layers electroplating metal deposits (ga
lvanische Metallabscheidung) (Multilayer electroplating (Mul
tilayergalvanik)) and are fixed directly above and below each other. The swirl disk is attached to the valve as follows:
That is, the vortex disk is designed so that its plane normal (Flaechennormale) extends obliquely at an angle deviated from 0 ° to the valve longitudinal axis, so that the direction of the vortex disk This gives a jet angle γ with respect to the longitudinal axis of the valve.

[0003] The above-mentioned known fuel injectors have the disadvantage, in particular, that they are expensive to manufacture and therefore expensive to manufacture.
Changing fuel injectors for any availability requires the use of cumbersome and expensive manufacturing means. In particular, the jet angles α and γ are adjusted by a general eddy current adjustment method (Drallaufbere
It is impossible to achieve by itungsmethode). Furthermore, the assembly of the vortex devices arranged on the outlet side is often only possible by accepting a number of separately mounted individual parts.

[0004]

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a fuel injection valve of the type described at the outset, which distributes fuel evenly along the inner wall of the injection opening or injection passage and has a conical peripheral wall. It is an object of the present invention to provide a fuel injection valve that can be injected into a combustion chamber in the shape of (1).

[0005]

SUMMARY OF THE INVENTION In order to achieve this object, according to an embodiment of the invention, the longitudinal axis of at least one swirl passage formed in the swirl device is 90 degrees with respect to the longitudinal axis of the injection passage. The fuel, which is oriented at an angle δ smaller than ° and flows through the fuel injection valve, moves in a spiral path along the inner wall of the injection passage.

[0006]

The fuel injection valve according to the present invention thus configured has the following advantages. That is, in the fuel injection valve according to the present invention, the swirl passage provided in the swirl device is oriented as follows, that is, the fuel is guided to a spiral orbit extending along the inner wall of the injection opening. Is extended over the length of the injection opening, such that the fuel can be distributed uniformly along the inner wall and injected into the combustion chamber in the form of a conical peripheral wall. The conical wall is in this case symmetrical and uniform, so that a stoichiometric cloud-like mixture of normal composition (stoechiometrische Gemischwolk)
e) is produced.

[0007] It is also advantageous if the vortex components are arranged downstream of the seal seat. With this configuration, simpler installation and higher compatibility (Kompatibilitaet) are advantageous for mass-produced fuel injection valves.
Is obtained.

[0008] Another advantageous configuration of the fuel injection valve according to claim 1 is described in claim 2 et seq.

It is particularly advantageous if the swirl channel is formed in the swirl device or in the valve seat. In this way, a good adaptation to the requirements for the fuel injection valve and a simple manufacture of the components are possible.

[0010] Further advantageously, the downstream arrangement of the swirl device allows a cardan-type valve needle guide, which valve needle guide or valve closure can be very accurate and offset. Not allow guidance.

In a further advantageous embodiment, the injection opening is designed to taper in the outflow direction through the step, so that the cloud-shaped mixture is more evenly symmetrical. Can be targeted.

In a further advantageous embodiment of the invention, the closing plate for closing the fuel injection valve on the outlet side is formed as a bowl or pot. With such a configuration, the number of necessary components can be reduced and the assembly can be simplified by this structural shape.

In a further advantageous embodiment of the invention, the vortex channels can be manufactured by different, less expensive methods, such as erosion, laser machining or stamping.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings.

The fuel injection valve 1 shown in FIG. 1A is configured in the form of a fuel injection valve 1 for a fuel injection device of an air-fuel mixture compression ignition type internal combustion engine. The fuel injector 1 is particularly suitable for directly injecting fuel into the combustion chamber of an internal combustion engine, not shown.

The fuel injection valve 1 comprises a nozzle body 2 in which a valve needle 3 is disposed. Valve needle 3
Is operatively connected to the valve closing body 4.
Forms a seal seat in cooperation with the valve seat surface 6 arranged on the valve seat body 5. The valve seat 5 can be inserted into the notch 50 of the nozzle body 2. In the illustrated embodiment, the fuel injector 1 is
The fuel injection valve 1 opens inward. The nozzle body 2 is sealed to the outer pole 9 of the magnet coil 10 by a seal member 8. The magnet coil 10 is encapsulated in a coil casing 11 and wound around a coil holder 12.
Is in contact with the inner pole 13 of the magnet coil 10. The inner pole 13 and the outer pole 9 are separated from each other by a gap 26, and are supported by a coupling member 29. The magnet coil 10 is connected to the electrical connector 1 via the conductor 19.
It is excited by the current that can be supplied by 7. The plug-in connector 17 is surrounded by a plastic peripheral wall 18, which can be injection molded on the inner pole 13.

The valve needle 3 is guided in a disk-shaped valve needle guide 14. To adjust the travel, a pair of adjusting disks 15 work. Adjustment disk 15
The mover 20 is located on the other side of the. This mover 20 is friction-coupled (kraftsch) via a first flange 21.
luessig) is connected to the valve needle 3, which is connected to the first flange 21 by a welding seam 22. A return spring 23 is supported on the first flange 21, which is preloaded by a sleeve 24 in the illustrated embodiment of the fuel injector 1.

The second flange 31 connected to the valve needle 3 via the welding seam 33 serves as a lower armature stopper. The elastic intermediate ring 32 resting on the second flange 31 avoids a collision when the fuel injector 1 is closed.

Fuel passages 30a and 30b extend into the valve needle guide 14 and the mover 20, and these fuel passages 30a and 30b are supplied through a central fuel supply section 16 and are filtered by a filter element 25. The fuel to be filtered is directed to the seal seat. The fuel injector 1 is sealed by a sealing member 28 to a fuel conduit (not shown).

A vortex device (Drallvort) is provided on the injection side of the valve seat body 5.
richtung) 34 is arranged. The nozzle body 2 is preferably formed as a disk and has an annular weld seam 37.
The injection passage 7 is formed in the swirl device 34 attached to the whirlpool. The vortex passage 35 guides the fuel from the seal seat to the injection passage 7. The eddy current device 34 will be described later with reference to FIGS.
This will be described in detail with reference to FIG. 1E.

When the fuel injection valve 1 is at rest, the mover 2
0 is loaded in a direction opposite to the stroke direction by the return spring 23, and the valve closing body 4 is held in a sealing contact state with the valve seat 6. When the magnet coil 10 is excited, the magnet coil 10 forms a magnetic field which causes the mover 20 to move in the direction of travel in the direction opposite to the spring force of the return spring 23, in which case the stroke is the inner pole 12 in the rest position. Is determined by a working gap 27 existing between the armature and the mover 20. The mover 20 includes a flange 2 welded to the valve needle 3.
1 is similarly carried in the stroke direction. The valve closing body 4 operatively connected to the valve needle 3 is lifted from the valve seat surface 6 and is guided to the injection opening 7 via the fuel passages 30a, 30b and the swirl passage 35 formed in the swirl device 34. Fuel is injected. The longitudinal axis 38 of the injection opening 7 is preferably inclined with respect to the longitudinal axis 36 of the fuel injection valve 1 at an injection angle γ.

When the coil current is interrupted, the armature 20 is separated from the inner pole 13 by the pressure of the return spring 23 after sufficient disappearance of the magnetic field, so that the flange 21 operatively connected to the valve needle 3 moves in the stroke direction. Exercise in the opposite direction. The valve needle 3 is thereby moved in the same direction, and the valve closing body 4 is brought into contact with the valve seat surface 6 and the fuel injector 1 is closed.

FIG. 1B is an enlarged sectional view of the injection side portion of the first embodiment shown in FIG. 1A of the fuel injection valve 1 constructed according to the present invention. This illustrated section is shown in FIG.
IB.

The swirl device 34, which is preferably constructed as a disk
Closes the nozzle body 2 on the ejection side. The vortex device 34 has an injection passage 7 formed therein, and at least one vortex passage 35 is eccentrically opened in the injection passage 7. The swirl passage 35 connects the volume chamber 39 formed on the outflow side of the seal seat with the injection passage 7. Swirl passage 3
5 is as follows, i.e., if this swirl channel 35 is displaced and the angle δ is different, the longitudinal axis 38 of the injection channel 7
Are oriented so as to extend substantially in parallel to. The angle δ is clearly smaller than 90 °.

In addition to the holding function for the valve seat surface 6, the valve seat 5 additionally assumes a guiding function for the valve closure 4 or the valve needle 3. The valve needle guide 41 is preferably designed as a kardanisch valve needle guide 41. As a result, it is possible to prevent the valve needle 3 and the valve closing body 4 from being centered and caught due to a manufacturing error. The valve seat 5 is preferably connected to the nozzle body 2 by a welding seam 42.

The vortex passage 3 has an angle δ with respect to the injection passage 7.
By tilting 5, the fuel is guided into the injection passage 7 such that the fuel enters the injection passage 7 with a tangential component. Then, the fuel in the injection passage 7 reaches the outlet 54 on the outflow side based on the applied centrifugal force.
Rotate as a wall thin film along the inner wall 40. Until the fuel flows out of the opening 54, the fuel proceeds along the swirling flow path along the inner wall 40, so that the amount of fuel is uniformly distributed around the entire circumference of the opening 54. The fuel jet injected into the combustion chamber of the internal combustion engine thereby has the shape of a hollow cone. From the shape of the hollow cone, there are no longer any vortex passages 35
Cannot be estimated in the swirl device 34 or how the swirl passage 35 is arranged in the swirl device 34. This makes it possible to find an advantageous and inexpensive combination of the axial thickness of the swirl device 34 or the swirl channel 35 for assembly.

FIG. 1C shows the valve seat body 5 in the area of the cardan type valve needle guide 41 in a section along the line IC-IC in FIG. 1B. In order to be able to guide the incoming fuel towards the sealing seat, the valve needle 3 or the valve closure 4 has at least one, in the preferred embodiment, four, grinding surfaces 43. The grinding surface 43 forms, together with the inner wall 44 of the valve seat body 5, a fuel passage 45 for guiding the fuel toward the seal seat. Between the fuel passages 45, the valve needle 3 or the valve closing body 4 is in contact with the inner wall 44 of the valve seat 5, thereby guaranteeing a cardan-type valve needle guide 41.

FIG. 1D shows a cross-sectional view of the eddy current device along the line ID-ID of FIG. 1B.

In the preferred embodiment shown, 3
Two swirl passages 35 are formed in an eroded manner or the like. These vortex passages 35 are in this case straightened by vortex devices 34 in order to generate vortices.
, But has a tangential component in the circumferential direction. When viewed in the outflow direction towards the cross section or plane of the drawing, three swirl passages 35 are visible, these swirl passages 35 extending obliquely through the swirl device 34 and ultimately not being visible in FIG. 1D. It is open to the passage 7.
That is, since the swirl passage 35 extends obliquely,
The fuel is provided with a kinetic component in the circumferential direction, and the kinetic component causes the injected cloud-like mixture (Gemisc
hwolke) is shaped into a hollow cone.

FIG. 1E shows one of the vortex passages 35 in a cross-sectional view along the line IE-IE in FIG. 1D.

The swirl channel 35 is preferably produced by erosion. To minimize the cost therefor, the length of the vortex passage 35 must likewise be minimized. In order to be able to direct the generated vortex in a predetermined direction and guide it to the inner wall of the injection passage 7, the vortex passage 3
It is desirable that the ratio of length to diameter of 5 is always at least 1 or greater. Alternatively, the vortex passage 35 is
Due to its small length, which is about 0.33 mm, it is also possible to produce using stamping or laser machining.

The vortex passage 35 is inclined at an angle δ with respect to a longitudinal axis 46 parallel to the longitudinal axis 38 of the injection passage 7, this angle δ being advantageously about 20 °.
And clearly less than 90 °, preferably 45 °
Less than.

FIG. 2 shows a second embodiment of the fuel injection valve 1 according to the invention in a sectional view in the region IB of FIG. 1A. In FIG. 2, the same members as those already described are denoted by the same reference numerals.

Unlike the first embodiment of the fuel injection valve 1 according to the invention shown in FIGS. 1A to 1E, the nozzle body 2 in the second embodiment shown in FIG. Has a protruding portion 47, which is formed as follows. That is, in this case, the valve seat body 5 is
8, supported by the projection 47, penetrating the notch 49 in the projection 47, and in this case the projection 47
And the valve seat 5 are flush with each other on the outflow side. The valve seat 5 is in this case a projection 47 of the nozzle body 2.
And in the area of the notch 49 using the welding seam 42.

At least one swirl passage 35 is formed in the valve seat 5 using the method described with reference to FIG.
It is open to. The injection channel 7 is in this case a closing plate 5
This closure plate 50 is likewise connected to the projection 47 of the nozzle body 2 in the outflow direction using welding. By forming the swirl passage 35 in the valve seat 5, the injection passage 7 can be given a shape that tapers in the outflow direction. This shape can be formed, for example, in a step-like manner by the steps 51, whereby the vortexed flow can be made uniform and symmetric over the entire circumference of the injection opening 7. The fuel first moves in a spiral trajectory along the inner wall 40 of the injection passage 7 until the fuel strikes the step 51. The impingement on the step 51 prevents fuel from flowing directly into the tapered part of the injection channel 7, which enhances the swirling motion and homogenizes the hollow cone which is then injected into the combustion chamber of the internal combustion engine. Is done. This stepped shape of the injection passage 7
It can only be manufactured if the closing plate 50 is manufactured as a unique component and the swirl channel 35 is already integrated into the valve seat 5.

FIG. 3 shows a third embodiment of the fuel injection valve 1 constructed as in the present invention in a sectional view in a region IB of FIG. 1A.

This third embodiment is different from the second embodiment.
It has a more compact structural shape. Swirl passage 35
Is similarly formed on the valve seat body 5, and the valve seat body 5 is arranged in a notch 52 at the center of the nozzle body 2 so that the valve seat body 5 contacts the inner wall 53 of the nozzle body 2. I have.
The injection passage 7 is formed in a closing plate 50 which is shaped like a pot or pot in the embodiment shown. This shape can be manufactured at a low cost by, for example, deep drawing. The assembly of the valve seat 5 and the closing plate 50 can also be performed simply and inexpensively by a single welding seam 37, which connects the valve seat 5 and the closing plate 50 with the nozzle body 2. I have.

The injection passage 7 is advantageously likewise provided with a step 51 in order to enhance the vortex flow of the fuel and to homogenize the injected cloudy mixture.

The present invention is not limited to the embodiment shown, but also for example for a fuel injector 1 with any number of swirl passages 35 and for any structural shape of the fuel injector 1. Can also be used.

[Brief description of the drawings]

FIG. 1A is a sectional view showing a first embodiment of a fuel injection valve according to the present invention.

1B is a cross-sectional view showing a first embodiment of the fuel injection valve according to the present invention shown in FIG. 1A in an enlarged manner in a region IB of FIG. 1A.

1C is a cross-sectional view of the embodiment shown in FIG. 1B, taken along line IC-IC.

FIG. 1D is a cross-sectional view of the embodiment shown in FIG. 1B taken along the line ID-ID.

1E is a cross-sectional view of the embodiment shown in FIG. 1D, taken along line IE-IE.

FIG. 2 shows a second embodiment of the fuel injection valve according to the present invention in FIG.
FIG. 4 is an enlarged cross-sectional view in a region IB of A.

FIG. 3 shows a third embodiment of the fuel injection valve according to the present invention in FIG.
FIG. 4 is an enlarged cross-sectional view in a region IB of A.

[Explanation of symbols]

1 fuel injection valve, 2 nozzle body, 3 valve needle,
4 valve closing body, 5 valve seat, 6 valve seat surface, 7 injection passage, 8 sealing member, 9 outer pole, 10 magnet coil, 11 coil casing, 12 coil holder, 13 inner pole, 14 valve needle guide,
15 adjusting disc, 16 fuel supply, 17 plug-in connector, 18 plastic peripheral wall, 19 conductor,
Reference Signs List 20 mover, 21 first flange, 22 weld seam, 23 return spring, 24 sleeve, 25
Filter element, 28 sealing member, 29 coupling member, 30a, 30b fuel passage, 31 second flange, 32 intermediate ring, 33 welding seam, 3
4 eddy current device, 35 eddy passage, 36 longitudinal axis, 37 weld seam, 38 longitudinal axis, 4
0 inner wall, 41 valve needle guide, 42 weld seam, 43 ground surface, 46 longitudinal axis, 47
Projection, 48 Shoulder, 49 Notch, 50 Closure Plate, 51 Step, 52 Notch, 53 Inner Wall, 54 Opening

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Jörg Heise Germany Wesigheim Elser-Ring 22 F-term (reference) 3G066 AA02 AD12 BA02 BA51 BA54 BA56 BA61 CC01 CC14 CC21 CC37 CC41 CD30 CE22 CE34

Claims (18)

[Claims] 1. A fuel injection valve (1) provided with a valve closing body (4), wherein the valve closing body (4) is provided on a valve seat surface (5) formed on a valve seat body (5). Together with 6), a sealing seat is formed, on the outlet side of which is arranged a swirl device (34) with at least one swirl passage (35) and an injection passage (7). In one form, the longitudinal axis (46) of the at least one swirl passage (35) formed in the swirl device (34) is at an angle of more than 90 ° to the longitudinal axis (38) of the injection passage (7). Are also oriented at a small angle (δ) and the fuel injector (1)
The fuel injection valve is characterized in that the fuel flowing therethrough moves in a spiral path along the inner wall (40) of the injection passage (7). 2. The fuel injection valve according to claim 1, wherein the swirl passage (35) is arranged eccentrically with respect to the injection passage (7). 3. The fuel injection system according to claim 1, wherein the swirl device (34) is formed in a disk shape and closes a nozzle body (2) of the fuel injection valve (1) on an outflow side. valve. 4. The longitudinal axis (38) of the injection passage (7).
4. The fuel injector according to claim 1, wherein the valve is inclined at an angle (γ) with respect to a longitudinal axis of the fuel valve. 5. 5. The valve seat according to claim 1, wherein the valve seat has a cardan-type valve needle guide in the region of the inflow side of the seal seat. Fuel injection valve. 6. At least one vortex passage (35) and an injection passage (7) are arranged in the vortex device (34).
A fuel injection valve according to any one of claims 1 to 5. 7. The fuel injection valve according to claim 1, wherein the axial length of the vortex passage is at least as great as its diameter. 8. The fuel injection valve according to claim 1, wherein the swirl passage (35) is formed in the swirl device (34) by erosion, punching or laser machining. 9. The fuel injection system according to claim 1, wherein the vortex passage has a tangential component axially with respect to its longitudinal axis. valve. 10. The fuel injection valve according to claim 1, wherein the vortex passage (35) is formed in the valve seat (5). 11. The fuel injection valve according to claim 10, wherein the injection passage (7) is formed in a closing plate (50) of the nozzle body (2). 12. The injection passage (7) tapers in the outflow direction while forming a step (51).
12. The fuel injection valve according to 0 or 11. 13. The nozzle body (2) has a protrusion (47) bent inward in the radial direction, and a cutout (49) is formed in the protrusion (47). The fuel injection valve according to any one of claims 10 to 12. 14. The fuel injection valve according to claim 13, wherein the valve seat (5) has a shoulder (48), the shoulder (48) being supported by a projection (47). 15. The valve seat (5) penetrates into a notch (49) of the projection (47) and is flush with the projection (47) on the outlet side. 13 or 14
A fuel injection valve as described. 16. A closure plate (50) having a projection (4).
16. The fuel injection valve according to claim 15, which is welded or brazed to (7) and covers the projection (47) on the outflow side. 17. The fuel injection valve according to claim 10, wherein the closing plate (50) is formed in a pot shape or a pot shape. 18. The pot-shaped or pot-shaped closing plate (50) is connected to the valve seat (5) and the nozzle body (2) by an annular welded seam (37).
7. The fuel injection valve according to 7.