JP2002195132A - Fuel injection valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To miniaturize a swirl member and reduce manufacturing cost of the same and enable the same to be easily installed on a fuel injection valve. SOLUTION: This invention relates to a fuel injection valve 1 especially for a type of directly injecting fuel into a combustion chamber of an internal combustion engine. In a fuel injection valve type provided with a valve closing body 4, valve seat body 5 and the swirl member 34, the swirl member 34 is twisted in a sleeve. The sleeve includes several tightened wires and the wires fill a notch of the sleeve, namely inside of the sleeve. A spiral hollow chamber is formed between the wires and an inner wall of the sleeve.

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, comprising a valve closing body and a valve seat (valve seat holding body). ), Wherein the valve closing body forms a seat valve in cooperation with the valve seat surface of the valve seat body, and further includes a swirl member.

[0002]

BACKGROUND OF THE INVENTION Published German Patent Application No. 197
In the fuel injection valve known from JP 36682A1, a guide and seat area is provided at the downstream end of the valve.
The guide and seat area is formed from three plate-shaped members. In this case, a swirl member is embedded between the guide member and the valve seat member. The guide member serves for guiding the axially movable valve needle through the guide member, while the valve closing section of the valve needle cooperates with the seat surface of the valve seat member. It is supposed to. The vortex member (member forming the vortex) has a plurality of vortex passages in an inner opening region, and the vortex passage is not connected to the outer periphery of the vortex member. The entire open area with the vortex passage extends completely over the axial thickness of the vortex member.

The disadvantages of the known fuel injectors are that they are complicated in construction, which, on the one hand, leads to high production costs and, on the other hand, the heterogeneity and asymmetrical jet and flow of the injected mixture or spray stream. An excessive amount of error occurs. This is particularly attributable to the fact that the injection direction in the oblique injection type fuel injection valve must be turned by a subsequent injection hole. Such turning creates asymmetry in the vortex and the jet. Furthermore, the conventional vortex forming means requires a high precision which cannot be realized.

[0004]

According to the present invention, the swirl member is formed by a plurality of wires that are twisted in a twisted string within the sleeve to form a hollow space for forming the swirl. It can be made small based on the small dimensions of the wires that are twisted into a twisted string to form the hollow chamber. Further, the swirl member can be easily mounted on any mass-produced fuel injection valve. By locating the swirl member downstream of the seat valve, any injection angle with respect to the longitudinal axis of the fuel injector is achieved without diverting the fuel jet.

[0005] Advantageous improvements of the fuel injection valve according to claim 1 are possible with the arrangement according to claim 2 and the following.

[0006] The wire is preferably made of tungsten or is made of glass fiber, since the diameter of the wire can be reduced to a minimum.

There is no need to impose high precision requirements on the sleeve, the receiving component and the wire, so that all components can be manufactured economically. Due to the simple construction of the receiving component and the sleeve, the assembly is extremely simple.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the illustrated embodiments. The illustrated fuel injection valve 1 is formed as an injection valve for a fuel injection device of an internal combustion engine of an air-fuel mixture compression ignition type. The fuel injector 1 is particularly suitable for injecting fuel directly into a combustion chamber (not shown) of an internal combustion engine.

The fuel injection valve 1 has a nozzle body 2 and a valve needle 3 disposed in the nozzle body. The valve needle 3 is operatively connected to the valve closure 4, which cooperates with a valve seat surface 6 arranged on the valve seat 5 to form a seat valve (seal seat). A valve seat 5 is inserted into a notch in the nozzle body 2. In the illustrated embodiment, the fuel injection valve 1 is a fuel injection valve of a system that opens inward. The nozzle body 2 is sealed from the outer magnetic pole 9 of the magnet coil 10 by a seal 8. The magnet coil 10 is wound around a coil support 12 and housed in a coil casing 11, and the coil support 12 is in contact with the inner magnetic pole 13 of the magnet coil 10. The inner pole 13 and the outer pole 9 are separated from one another by a gap 26 and are supported by a coupling component 29. The magnet coil 10 is supplied with electric current through the conducting wire 19 and the electric insertion contact 17. The plug contact 17 has a plastic coating 18 formed, for example, by injection molding.
, And the plastic coating may also surround the inner pole 13.

The valve needle 3 is guided in a plate-shaped or disk-shaped valve needle guide 14. An adjusting plate 15 which is paired with the valve needle guide is used for adjusting the stroke. The armature 20 is arranged on the side of the adjustment plate 15 opposite to the valve needle guide, and the armature is connected to the valve needle 31 via a first flange 21 so as to be able to transmit force. Flange 21 is weld seam 2
It is connected to the valve needle by 2. The return spring 23 is supported by the first flange 21 and the return spring 2
3 are clamped, ie prestressed, by a sleeve 24 in the embodiment shown.

A second flange 31 is connected to the valve needle 3 by means of a weld seam 33 and serves as a lower armature stopper. An elastic intermediate ring 32 is arranged on the second flange 31 and prevents the fuel injection valve 1 from rebounding when the fuel injection valve 1 is closed.

The fuel passages 30a and 30b provided in the mover 20 and the valve needle guide 14 are used to supply the fuel supplied from the central fuel supply section 16 and filtered by the filter member 25 to the injection opening 7 of the fuel injection valve. Guide towards. The fuel injection valve 1 is connected to a fuel line (not shown) by a seal 28.
Sealed against.

A vortex member 34 is arranged downstream of the seat valve, and the vortex member (vortex module) is preferably inclined at a predetermined injection angle γ with respect to the longitudinal axis 35 of the fuel injection valve 1. ing. The swirl member 34 is shown in detail in FIGS.

When the fuel injection valve 1 is stationary, the mover 20
Is loaded by the return spring 23 in the direction opposite to the stroke direction,
Therefore, the valve closing body 4 is kept close to the valve seat surface 6. By exciting the magnet coil 10, the magnet coil 10
Forms a magnetic field, which causes the mover 20 to move in the stroke direction against the spring force of the return spring 23, in which case the stroke is stationary and exists between the inner magnetic pole 13 and the mover 20. It is defined by the gap 27. Mover 20
However, it carries the flange 21 welded to the valve needle 3 and thus the valve needle in the stroke direction. by this,
The valve closing body 4 operatively connected to the valve needle 3 is separated from the valve seat surface 6 and the fuel is guided to the injection opening 7 via the fuel passages 30a and 30b.

When the coil current is cut off, the mover 20 is separated from the inner magnetic pole 13 by the pressure of the return spring 23 based on sufficient collapse (extinction) of the magnetic field, and as a result, the flange 21 is turned in the direction opposite to the stroke direction. Exercise. Accordingly, the valve needle 3 is moved in the same direction, and the valve closing body 4 is brought into contact with the valve seat surface 6, whereby the fuel injection valve 1 is closed.

FIG. 2 is an enlarged partial sectional view of the injection side portion of the first embodiment of the fuel injection valve 1 shown in FIG. The valve seat surface 6 of the valve seat body 5 has a valve closing body 4 formed on the valve needle 3.
It is designed to work with. A swirl member 34 is disposed downstream of the seat valve, and the swirl member 34 has a vertical axis 36 of the swirl member 34 at an angle γ with respect to a vertical axis 35 of the fuel injection valve 1.
It is aimed at forming. Thereby, the longitudinal axis 36 of the swirl member 34 is aligned with the jet axis of the fuel jet, so that the jet redirection and thus the non-uniformity and asymmetry caused by the jet redirection are avoided.

The swirl member 34 has a receiving component 37, which comprises the injection opening 7 and the swirl chamber 38 and receives the original swirl unit 39.
The receiving component 37 may be formed, for example, in the form of a cylinder and may be fitted in a corresponding recess 47 of the valve seat 5. A swirl chamber 38 is arranged downstream of the swirl unit 39 and tapers into the jet opening 7 in the flow direction.

FIG. 3 is a schematic sectional view of the fuel injection valve having a different diameter of the valve seat body 5 taken along a line III-III in FIG. Since the valve seat 5 of the embodiment shown does not have a hole for the fuel passage, i.e., a hole for the fuel guide, the valve closure 4 is provided with at least one grinding portion (chamfer) in the area of the valve seat 5. Part) 40. In the embodiment shown, four grinding parts 40 are formed in the valve closure 4 for symmetry reasons, so that the volume 41 between the valve closure 4 and the valve seat 5 avoids turbulence on the one hand. Therefore, it is kept small and on the other hand large enough to avoid throttling. As a result, the movement of the valve needle 3 or the guidance of the valve closing body 4 in the valve seat 5 is perfectly achieved on the basis of the balance of the radial forces.

FIG. 4 is a schematic sectional view of the eddy current unit 39 in a region indicated by reference numeral IV in FIG. Eddy current unit 39
Is a plurality of thin wires, three wires 4 in the preferred embodiment shown.
The wire may be made of, for example, tungsten or formed as glass fiber. A wire 42 is arranged in the notch 43 of the sleeve 44 and almost completely fills the notch. Hollow chambers 45 are formed between the wires 42, and the hollow chambers serve for fuel guidance. In this case, each hollow chamber 45 acts as a flow passage (flow passage). In order to form a vortex (helical flow), the cavity 45 must extend spirally in the sleeve 44. A corresponding shape is achieved by twisting the wires 42 into one another in the notch 43 of the sleeve 44. The torsion of the wire 42 reduces the axial length of the braid made of the wire 42, while increasing the entire wire or the cross-sectional area of the braid, so that the wire is It comes into contact with the inner wall 46 and is tightened. As a result, the wire 42 is fixed in the sleeve 44. As an alternative embodiment, the wire 42 may be clamped by compression (squashing) of the sleeve 44.

Since the wire 42 can be made very thin, the entire swirl member 34 is correspondingly kept small. Thus, the dead volume of the swirl chamber 38 arranged downstream of the swirl unit 39 can likewise be significantly reduced, so that swirl is obtained in the swirl chamber even between the two injection cycles of the fuel injector 1 and is kept homogeneous. .

FIG. 5 shows the vortex unit 39 shown in FIG.
FIG. 5 is a schematic sectional view taken along line VV in FIG. 4.

In the embodiment shown, the swirl unit 39 has three wires 42, which are arranged in notches 43 in a sleeve 44. The wire 42 is in contact with the inner wall 46 of the sleeve 44. The residual volume not filled by the wire 42 forms a hollow space 45, which functions as a flow passage.

The mass-produced fuel injection valve 1 is
Due to the small size of the vortex member, the vortex member can be equipped without any problem. The receiving hole 4 of the valve seat 5 into which the swirl member 34 is inserted.
7 is simple and economical to form. The individual components of the swirl element 34 are likewise easily assembled, so that the production effort and the production costs are significantly reduced compared to the conventional swirl generating means arranged on the inlet side of the seat valve.

The present invention is not limited to the embodiment shown, but may be used for fuel injectors having a large number of wires 42 as well as for fuel injectors of any construction.

[Brief description of the drawings]

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

FIG. 2 is a schematic cross-sectional view of an embodiment of the fuel injection valve according to the present invention in the region indicated by II in FIG. 1;

FIG. 3 is a schematic sectional view taken along the line III-III in FIG. 2;

FIG. 4 is a schematic cross-sectional view of the fuel injection valve according to the present invention in a region indicated by reference numeral II in FIG. 2;

FIG. 5 is a schematic sectional view taken along line VV in FIG. 4;

[Explanation of symbols]

Reference Signs List 1 fuel injection valve, 2 nozzle body, 3 valve needle, 4 valve closing body, 5 valve seat body, 6 valve seat surface, 7 injection opening, 8 seal, 9 outer magnetic pole, 10 magnet coil, 11 coil casing, 12 coil support Body, 13 inner magnetic poles,
14 valve needle guide, 15 adjustment plate,
16 fuel supply part, 17 plug-in contact, 18 plastic coating, 19 conductor, 20 mover,
21 Flange, 22 Weld seam, 23
Return spring, 24 sleeve, 25 filter member, 26 gap, 27 working gap, 2
9 coupling components, 30a, 30b fuel passage,
31 flange, 32 intermediate ring, 33 weld seam, 34 eddy member, 35 longitudinal axis,
36 vertical axis, 37 receiving component, 38 swirl chamber, 39 swirl unit, 40 grinding unit,
41 capacity, 42 wire rod, 43 notch (inside), 44 sleeve, 45 hollow chamber, 4
6 inner wall

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B05B 1/34 101 B05B 1/34 101 (72) Inventor Detlef Novak Germany Untergruppenbach J. Capisharde (72) Inventor Jörg Heize Weißheim, Germany 22 F term (reference) 3G066 AA02 AB02 BA61 CC05U CC14 CC27 CC37 CC41 CD14 CD15 CE22 4F033 AA13 BA03 CA14 DA01 EA01 GA02 GA10 KA02 NA01

Claims (13)

[Claims] 1. A fuel injection valve (1) comprising a valve closure (4) and a valve seat (5), said valve closure cooperating with a valve seat surface (6) of the valve seat. And forming a seat valve, and further comprising a swirl member (34),
The vortex member (34) has a plurality of wires (42) twisted together within one sleeve (44) and clamped within the sleeve (44), the wires being of the sleeve (44). The notch (43) is filled as follows,
That is, the inner wall (46) of the wire (42) and the sleeve (44).
A spiral hollow chamber (45) is formed between the fuel injection valve and the fuel injection valve. 2. The fuel injection valve according to claim 1, wherein the hollow space (45) between the wire (42) and the inner wall (46) of the sleeve (44) is formed as a flow passage. 3. The fuel injector according to claim 1, wherein the wires are twisted in a twisted string. 4. The fuel injection valve according to claim 1, wherein the number of wires (42) is at least three. 5. The fuel injection valve according to claim 1, wherein the wire (42) is made of tungsten. 6. The fuel injection valve according to claim 1, wherein the wire (42) is made of glass fiber. 7. The cross section of the wire (42) is dimensioned as follows: the wire (42) is clamped in the sleeve (44) by twisting the wires together. 7. The fuel injection valve according to any one of claims 1 to 6. 8. The fuel injection valve according to claim 1, wherein the sleeve (44) is formed as a hollow cylinder. 9. A sleeve (44) having a receiving component (3).
9. The fuel injection valve according to claim 8, wherein the fuel injection valve can be inserted into the fuel injection valve. 10. The sleeve (44) has a receiving component (3).
The fuel injection valve according to claim 9, wherein the fuel injection valve is welded, brazed, or interference-fitted inside. 11. The fuel injection valve according to claim 10, wherein the receiving component has a swirl chamber downstream of the sleeve, the swirl chamber narrowing leading to the injection opening. . 12. The receiving component (37) comprising a valve seat (5).
The fuel injection valve according to any one of claims 8 to 11, which can be inserted into the receiving hole of the fuel injection valve. 13. The fuel injection according to claim 1, wherein the swirl member is inclined at an injection angle (γ) with respect to a longitudinal axis (35) of the fuel injection valve (1). valve.