JPS6073043A - Fuel injector for internal combustion engine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a fuel injection device for an internal combustion engine, comprising at least one injection nozzle and an incandescent coil 7 connected behind the injection nozzle. The fuel/jet stream passes through the incandescent coil without contact, and an air opening opening from the side is formed in the passage of the fuel/jet stream. It relates to those types in which air passes from the combustion chamber into the edge area of the fuel jet stream.

PRIOR ART A fuel injection device of the type mentioned above has the advantage that braking of the jet stream due to the formation of negative pressure and deformation of the jet stream in the incandescent coil is practically avoided at all times during the operation of the internal combustion engine, so that the jet stream follows the desired geometrical shape. It has the advantage that it can flow out of the incandescent coil at maximum speed without being braked. The air drawn in from the side inside the incandescent coil is heated and enters the edge zone of the jet stream, where, unlike the center zone, relatively fine fuel particles are present and the jet center A very good fuel/air ratio for ignition and combustion results due to the fuel particle density which is smaller than 100%. When flowing through the incandescent coil, heat is supplied to the edge area of the jet, so that upon entry of the jet into the combustion chamber, the jet center 7a: 'surrounding fuel grains,
A jet fuel film of steam and air ignites. Since the jet fuel film is only a proportionately small portion of the total jet volume, incandescent devices for inducing ignition require relatively little heating energy. In this case, the incoming energy of the jet is not reduced, so that the jet spreads unhindered in the combustion chamber with the burning circumferential section.

The incandescent coil is formed by a heating wire made of precious metal and a fully formed part, which is connected at one end to a current supply conductor and at the other end to a cuff 0 cell surrounding the incandescent coil. connected and earthed via the protection capsule. Although such a construction is simple and dimensionally stable in itself, it has disadvantages with regard to assembly.

Effects of the invention Compared to the prior art, in the design according to the invention, both connections of the incandescent coil to the subsequent conductor are omitted, and the correspondingly preformed heating conductor, known under the name coaxial heating conductor, is completely replaced. is fixed to the injection nozzle as a single unit, which simplifies assembly of the components. Furthermore, precious metals are saved, which makes incandescent coils cheaper. The shape-stable coated heating conductor forms a rigid structural unit with the insulating material surrounded by the coat and the internal heating wire, so that it cannot be deformed by the thermal and mechanical forces generated during operation. Never.

Advantageous embodiments of the invention are described in the following claims.

In devices in which the injection nozzle casing consists of two parts (nozzle body and nozzle holder) connected to each other by a cap nut, the coaxial heating element forming the incandescent coil is advantageously fixed to the cap nut, so that the injection opening There is no need for the nozzle body to be modified with respect to its normal construction.

The heating conductor is tightly fixed between the bearing surface of the cap 0 nut that is matched to the new surface shape of the heating conductor and the facing surface of the ring member fixed to the cap 0 nut that is matched to the 1 position. Then, fix the heating conductor to the cap nut accurately and reliably. The heating conductor may be fixed by clamping or by gluing or both.

The ring member is preferably constructed so as to surround the heating section forming the incandescent coil of the heating conductor at a radial spacing. At the same time, this creates a flow path for the combustion air, which is drawn from the combustion chamber force by the fuel jet stream through the individual windings of the incandescent coil.
tZNo.Moreover, the cap nut is the combustion chamber 11.
The cap has a conically tapering peripheral wall section at its end, in which a bearing surface for the heating conductor is formed, and the opposite surface corresponds to a hole wall section which widens at the same cone angle of the ring element. Look at the formation. The link part number is advantageously welded to the cap nut.

The exemplary injection nozzle 10 has a nozzle body 12 in which a valve seat 14 is formed and a valve knee 16 is slidably supported.

The valve needle has a sealing cone 18 cooperating with the valve seat 14, to which a throttle pin 20 is connected,
The aperture pin projects into the injection opening 22 of the nozzle body 12. The injection opening 22 opens at the end 24 of the injection nozzle 10 facing the combustion chamber, which end face forms a conical wall section 2.
6 to the nozzle body 12 θ) cylindrical θ) peripheral surface.

The nozzle body 12 is normally clamped together with the intermediate plate 30 by means of a cap 711 and an intermediate plate 30 (not shown), and the nozzle 711 has connections for the fuel conduit. [1] γ 115 is provided with a chamber for receiving a closing spring, which presses the valve needle 16 against the valve 114 i 4. Cap 0 naso l-28&-, 1. Nozzle A (A\12θ)
It is fitted with a correspondingly conical σ) hole 31. / Zurholugka et al. (earth intermediate) 0re-1-
The fuel passage is connected to the nozzle body 12 through the ring groove 3
2 and connects the upper supply pipe 34 to the link ``It''.
It is connected to the pressure chamber 36 via the valve needle 1.
6 has a pressure shoulder 38 in the area of the pressure chamber 36, on which the fuel pressure valve J exerts a force against the closing spring to move the valve needle in the opening direction.

Coaxially connected to the rear of the injection nozzle is an incandescent coil 40, which incandescent coil forms a passage through which a fuel jet stream 42 can pass in contact. The incandescent coil 40 is surrounded by a ring member 44 at a distance in the radial direction, and the ring member 44 is attached to the cap nut 28 at 450 points. During operation of the internal combustion engine, a fuel jet stream 42 passes through the incandescent coil 40.
draws air from the relatively high oxygen content area of the combustion chamber through the gaps 46 between the individual turns of the incandescent coil 40 and the ring gap 48 formed between the incandescent coil and the ring member 44. The incoming air is heated by the incandescent coil 400 to a level higher than the normal temperature of the combustion chamber, and inside the incandescent coil 40 the fuel and jet stream 42 are heated.
The incandescent coil 40 and the so-called coaxial heating conductor 50 are covered with a shape-stable coating, and the fuel-air mixture, which is extremely good for ignition and combustion, enters the green area of the combustion chamber and reliably ignites under pressure. It is formed by a heating section 49 (FIG. 2) of 1. The 11° current supply section 52 is integrally connected to the heating section 49 by a transition section 54. 111If+・IJ.

The thermal conductor 50 has two heating wires 56, 58 inside, which have a relatively high electrical resistivity and whose ends 60 are welded together. Heating wire 56.58 is transition category 5
4 are connected to connecting conductors 62, 64, which have a very low electrical resistivity and a larger cross section than the electric heating conductors 56, 58. The heating wires 5.6.58 and the connecting conductors 62.64 are embedded in ceramic wires 66, preferably metal wires, and are made of a material with good thermal conductivity and heat resistance, for example Inconel. It is surrounded by a covering 68. Such a structure is a coaxial heating conductor 50
High unique edict 11 Surname yy t= 5 &y>it+
n k V fA-A Q lz J-/) and +v E
The V-shaped incandescent coil 40 is not deformed by thermal and mechanical loads during operation. Due to the different thermal resistivities and cross-sections, the temperature of the connecting conductors 62 and 64 increases only to a very high degree or to the temperature of the injection nozzle 10.

A coaxial heating conductor 50 is secured to the cap nut 28 by a ring member 44. For this purpose, the cap nut 28 has a conically tapered force cylinder wall section 70, on which the same conical bore wall section 7 of the ring element 44 is provided.
2 are in contact. Cap 0 nut 28 is peripheral wall section 7
0 has a groove-like recess 74 at one location, into which a groove-like recess 76 of the hole wall section 72 of the ring part paulownia 44 fits. This forms a passage through which the conductor section 78 of the coaxial heating conductor 50 is introduced. The two groove-like recesses 74 and 76 have a cross section that matches the cross-sectional shape of the conductor section 78 with a small gap, which gap is pressure-tight for fixing the coaxial heating conductor 50. At the same time, it is filled with adhesive that has a sealing effect.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention, and FIG. 2 is a partial sectional view of the incandescent coil of the embodiment of FIG. 10... Injection nozzle, 12 - Nozzle body, 14...
Valve seat, 16, valve needle, 18, seal cone, 20...
・Aperture pin, 22-・Injection opening, 24・・End face, 26・
...Wall section, 28. Cap 0 nut, 30. Intermediate plate, 31. Hole section, 32-IJ song groove 34... Supply pipe line, 36- EE force chamber, 38 Pressure shoulder, 40. Incandescent coil. , 42 Fuel/injection flow, 44...Ring member, 46-Gap, 48-Ring gap, 49-Heating section,
50. Coaxial heating conductor, 52. Current supply classification, 54
Transition section, 56 and 58... heating wire, 60 one end, 62
and 64...Connection I reading wire, 66...Excellent material, 68.Coating, 70...Surrounding wall section, 72...Hole wall section, 74 "1 F+01 ql. 6.2 Continued from page 1 0 shots Between Yvan φ Komarov Toy [Co., Ltd.] Inventor Werner Grieu Donwart Reitz Federal Republic of Gensburg φ Schwabelwiser Väke 13 Federal Republic of Germany Kerlingen Rob Schumannstose 21

Claims (1)

[Claims] 1. A fuel injection device for an internal combustion engine, which has at least one injection nozzle and an incandescent coil connected to the rear of the injection nozzle, and injects fuel through the incandescent coil.
The jet stream passes through without contact, allowing the fuel and
of the type in which an air opening opening from the side is formed in the passage of the jet stream, through which air can reach from the combustion chamber by injector action into the edge area of the fuel jet stream. In one embodiment, the incandescent coil (40) is constituted by a correspondingly shaped heating section (49) of a dimensionally stable coated heating conductor (50), and the heating conductor is formed by a heating section (49) or an incandescent coil (40). ) Fuel injection device for an internal combustion engine, characterized in that it is fixed to the injection nozzle jv (10) via a cold current supply section 52 which is integrally connected to the injection nozzle jv (10). 2. The injection nozzle casing consists of two parts, both parts are connected to each other by a cap nut (28), and the heating conductor (50) is fixed to the key 1 knob nut (28). Range 81'J,
The fuel injection device according to item 1. 6 between the bearing surface of the heating conductor (5o) adapted to the heating conductor cross-sectional shape of the cap nut (28) and the correspondingly adapted opposing surface of the ring member (44) fixed to the cap nut (28)K; 3. The fuel injection device according to claim 2, wherein the fuel injection device is compressively fixed to the fuel injection device. 4. The ring member (44) surrounds the heating section (49) forming the incandescent coil (40) of the heating conductor (5o) with a radial spacing (48). Fuel injection device as described. 5. The cap neck (28) has a conically tapered peripheral wall section (70)'a= at its end facing the combustion chamber, in which a bearing surface for the heating conductor (50) is formed. 5. A fuel injection device according to claim 3, wherein the opposite surface (76) is formed in a hole wall section (72) that widens at the same cone angle of the ring member (44). 6. The ring member (44) is welded to the cap device.