DE102018001566A1 - Dual-fuel fuel injector - Google Patents

Abstract

Dual-fuel fuel injector (1), comprising: - at least one lift-controllable fuel gas nozzle valve member (5) for the selective opening and closing of at least one nozzle opening (49) of a nozzle arrangement (51) of the dual-fuel fuel injector (1), a Hubsteueranordnung (13) per fuel gas nozzle valve member (5), which Hubsteueranordnung (13) works hydraulically according to the principle of a double-acting cylinder, characterized in that- a respective fuel gas nozzle valve member (5) via one hold-down assembly (25) with a "Machined Spring" (63) is loaded in the closing direction (A).

Description

The present invention relates to a dual-fuel fuel injector according to the preamble of claim 1.

In generic dual-fuel fuel injectors according to 1, s , for example, the patent DE 10 2015 016 034 B3 , which are provided for operation with fuel gas and a further fuel, preferably liquid fuel, a Stelzenelement loaded with a particular catchy wire compression spring, designed as a helical spring, is received in a passage fuel gas storage space. With the spring and continue gas pressure loaded Stelzenelement a closing force is exerted on a fuel gas nozzle valve member so that in case of failure of the switching system, the fuel gas nozzle valve members against the combustion chamber pressure can be reliably spent in the closed position. Since the spring chamber is also used for fuel gas storage, a barrier fluid seal is arranged on the guide of the stilt, which prevents fuel gas unintentionally creeps into the fuel gas nozzle valve member control circuit, which operates with a control fluid. Since, however, the barrier fluid pressure is greater than that of the fuel gas, barrier fluid is inadvertently introduced into the fuel gas to be expelled, thus adversely affecting emissions.

Proceeding from this, the present invention has the object to provide a dual-fuel fuel injector of the aforementioned type, which overcomes the disadvantages of the prior art.

This object is achieved by a fuel injector with the features of claim 1.

Advantageous developments and embodiments of the invention are specified in the further claims.

According to the invention, a two-component or dual-fuel fuel injector is proposed for an internal combustion engine, preferably for a reciprocating internal combustion engine. Such an internal combustion engine can be configured as a self-igniter and / or a spark igniter, generally as a dual-fuel engine, in particular as a large engine. Advantageously, the use of the dual-fuel fuel injector is e.g. in the context of a Zündstrahlbetriebs an internal combustion engine. The dual-fuel fuel injector is preferred for use with a first fuel in the form of fuel gas, e.g. Natural gas, biogas, landfill gas, hydrogen or the like, and a second fuel, preferably in the form of liquid fuel, e.g. Diesel fuel, bio oil, heavy oil or similar

For example, the internal combustion engine having the dual-fuel fuel injector for a motor vehicle such as a ship, a rail vehicle such as a locomotive, a utility or special vehicle or e.g. for a stationary device, e.g. for a combined heat and power plant, an (emergency) generating set, and also for industrial applications, e.g. offshore or onshore. In the context of an internal combustion engine, the dual-fuel fuel injector can be used in particular with a fuel injection system thereof, preferably with a common-rail fuel injection system, for example both for fuel gas and the further fuel, preferably liquid fuel.

The dual-fuel fuel injector has at least one lift-controllable fuel gas nozzle valve member, preferably in the form of a fuel gas nozzle needle, which is provided in particular for the selective opening and closing of at least one nozzle opening of an (associated) nozzle arrangement of the dual-fuel fuel injector , Preferably, the dual-fuel fuel injector has a plurality of such lift-controllable fuel gas nozzle valve members, e.g. three or more, and more particularly in an arrangement in which they provide a centrally located nozzle valve member for the discharge of another fuel - e.g. Surrounded by a circular line, in particular a liquid fuel nozzle valve member of the dual-fuel fuel injector surrounded (in three nozzle valve members, for example in a triangular arrangement). A respective fuel gas nozzle valve member can be accommodated and guided axially displaceable in a correspondence receptacle, in particular designed as an axial bore, further preferably each formed in a nozzle body of the dual-fuel fuel injector.

The dual-fuel fuel injector further includes a Hubsteueranordnung per fuel gas nozzle valve member. The respective Hubsteueranordnung works hydraulically and in particular according to the principle of a double-acting cylinder. In this case, the respective stroke control arrangement preferably comprises a piston section (which acts as a piston) which is formed or connected to a fuel-distant end of the fuel gas nozzle valve member to be controlled via the stroke control arrangement, furthermore a first control chamber closer to the nozzle and a second control chamber remote from the nozzle the piston section are separated from each other volume variable (so far form a hydraulic cylinder with therein (axially) displaceable piston).

According to the principle of the double-acting cylinder, a control line is preferably routed to a respective control chamber of the stroke control arrangement, and in each case, in particular, via a changeover valve (servo valve or pilot valve) to a respective control line respective control room. The switching valve (which further preferably communicates with a hydraulic pressure source (control fluid) and a hydraulic pressure sink (leakage)), may in particular be a 4/2-way valve, wherein each one control chamber in the context of the Hubsteueranordnung formed - via switching the switching valve - can be relieved hydraulically while the other is loaded and vice versa. Preferably, the fuel gas nozzle valve member from the nozzle near control chamber towards the nozzle assembly turns out of the control room, as far as in the preferably subsequent correspondence recording.

According to the invention, in the case of the proposed dual-fuel fuel injector, a respective fuel gas nozzle valve member is loaded in the closing direction via a respective hold-down arrangement with a so-called "Machined Spring", in particular designed as a compression spring. As "Machined Spring", as the technical term is referred to in the present invention, a spring which, in contrast to conventional (wire-based) coil springs not wound from a wire, but "worked out of the solid", preferably machined, e.g. by milling, eroding, laser cutting or a similar process. The thus made of a solid material or solid metal, e.g. Titanium, stainless steel or high-strength alloys machined springs can advantageously be made shorter or more compact compared to conventional coil springs, besides being advantageous as precision springs, e.g. with all linear spring characteristic (so that a bias for such a linear characteristic as in conventional coil springs is not required). Furthermore, seating or contact surfaces or generally special geometries can be integrated as required in the "Machined Spring" or be integrated with.

In the context of inventively provided hold-down arrangement (per fuel gas nozzle valve member) is provided to take this "Machined Spring" in a spring chamber of the hold-down arrangement, which is preferably formed at the nozzle remote fuel gas nozzle valve member or provided with the spring chamber also preferably also - nozzle-distant - Control room is formed (in particular as a common volume). Hereby, the "machined spring" may be urged directly against the fuel gas nozzle valve member - a closing force exerted on it - in preferred embodiments e.g. indirectly via a stilts element. Especially in embodiments in which the "Machined Spring" is directly against the fuel gas nozzle valve member in Appendix, due to the simple feasibility of "Machined Springs" with fully planar and level same investment face improved force distribution and support against wire-based coil springs can be achieved.

In embodiments with a stilt element, this may be provided with a e.g. bolt or pin-shaped portion in the middle of or within the wound space or within the windings of the "Machined Spring" recorded or arranged, in particular guided on the turns (thus reliably avoid buckling of the "Machined Spring"), the stilt element close to the nozzle For example, further comprises a spring plate against which the "Machined Spring" is supported at one end or pushed. In this case, a (short) engagement section or extension of the stilt element can be urged by the spring plate then, for example, against the fuel gas nozzle valve member (against a nozzle-remote end face thereof). Jet Remote is the "Machined Spring" e.g. supported against an end face of the spring space, preferably against e.g. against an adjusting element between the spring end and spring chamber end face, with which adjustment element, if necessary, a bias against the fuel gas nozzle valve member is adjustable. Such an adjustment element is preferably a disk, e.g. a perforated or annular disk, wherein the adjustment can advantageously be made simply by selecting the thickness of the adjusting element.

With the invention, the hold-down arrangement over prior art hold-down arrangements with wire-based coil spring - especially as discussed at the beginning - to perform significantly reduced space, along with the advantage of the spring chamber no longer than fuel gas passage memory - previously the pronounced lack of space (in the area above the nozzle body ) owed - to have to perform, but the fuel gas (high pressure) supply lines - now correspondingly larger dimensions, insofar as, for example also with intermediate storage functionality - to be able to lead directly to the nozzle arrangements or an upstream nozzle space directly or without a specially formed buffer in the injector housing. In this way, in turn, the previously required barrier fluid seal on the hold-down arrangement or the stilt element can advantageously be dispensed with, so that the barrier fluid entry into the fuel gas is likewise avoided in the intended manner. In addition, but also accounts for unintentional turbulence in the fuel gas supply path to the nozzle assembly due to the fact that this no longer needs to be performed on the spring chamber (fuel gas buffer).

Overall, the benefits associated with "machined springs" outweigh the significantly higher costs - unexpected in itself. In advantageous embodiments, a respective "Machined Spring" a be mehrgängige, for example, two-speed or three-speed spring, in which the spring force can be distributed even more evenly parallel to the central axis of the spring. As a result, the compression or expansion is translated more precisely (axially) in parallel (ie as the number of gears increases). This can also be omitted, for example, a spring-guided bolt or pin element.

In the context of preferred embodiments of the dual-fuel fuel injector, a respective spring chamber is all formed in an intermediate plate of the dual-fuel fuel injector, in particular as a blind hole or bore, furthermore in particular with correspondence dimensions in relation to the "Machined Spring" ever received therein, so that it can be guided radially on the outside and, furthermore, a possible buckling (radially outwards) is also effectively avoided thereby. Due to the fact that the spring chamber with such a configuration can be operated effortlessly from one end face into the intermediate plate (or alternatively a different housing element of the dual-fuel fuel injector), the production of the hold-down arrangement is also extremely simple.

In particular, in the context of a hold-down arrangement as configured above, it is provided that the respective fuel gas nozzle valve member is all received in a nozzle body of the dual-fuel fuel injector, and the nozzle body is preferably capped by means of the intermediate plate. In this case, in the nozzle body preferably both the correspondence recording for a respective fuel gas nozzle valve member and the (nozzle-remote) cylinder wall section to form the control chambers and receiving the piston portion worked (especially as a bore), in particular depending also from a (nozzle remote) end face (against which the intermediate plate is provided for covering the system). In that regard, the Hubsteueranordnung can be completed in a simple manner by joining the intermediate plate and nozzle body, preferably such that the spring chamber preferably forms a common volume in the course of assembly with a control chamber part of the nozzle-remote control chamber.

Finally, an internal combustion engine, in particular the reciprocating piston type, which has at least one dual-fuel fuel injector as discussed above, is also proposed.

Further features and advantages of the invention will become apparent from the following description of embodiments of the invention, with reference to the figures of the drawings, which show details essential to the invention, and from the claims. The individual features may be implemented individually for themselves or for a plurality of different combinations in a variant of the invention.

• 1 exemplarisch und schematisch eine teilgeschnittene und abgebrochene Ansicht eines gattungsgemäßen Dual-Fuel-Kraftstoffinjektors nach dem Stand der Technik.
• 2 exemplarisch und schematisch eine teilgeschnittene und abgebrochene Ansicht eines Dual-Fuel-Kraftstoffinjektors gemäß einer bevorzugten Ausführungsform der Erfindung.
• 3 exemplarisch und schematisch eine Detailansicht eines Details aus 2, fokussiert auf die „Machined Spring“.
• 4 exemplarisch und schematisch eine Ansicht einer Zwischenplatte des Dual-Fuel-Kraftstoffinjektors gemäß 2.

Preferred embodiments of the invention are explained below with reference to the accompanying drawings. Show it:

• 1 exemplary and schematically a partially cut and broken view of a generic dual-fuel fuel injector according to the prior art.
• 2 by way of example and schematically a partially sectioned and broken view of a dual-fuel fuel injector according to a preferred embodiment of the invention.
• 3 exemplary and schematic detail of a detail from 2 , focused on the "Machined Spring".
• 4 exemplary and schematically a view of an intermediate plate of the dual-fuel fuel injector according to 2 ,

In the following description and the drawings, the same reference numerals correspond to elements of the same or comparable function. Elements of the prior art are provided with primed reference numerals.

1 shows a dual-fuel fuel injector 1' According to the state of the art. The dual-fuel fuel injector 1' has a nozzle body 3 ' in which a number of fuel gas nozzle valve members 5 ' (only one fuel gas nozzle valve member 5 ' is shown) received axially displaceable and guided. An end portion of the respective fuel gas nozzle valve member 5 ' is as a piston section 7 ' executed, wherein the piston portion 7 ' two control rooms 9 ' . 11 ' a respective one (the fuel gas nozzle valve member 5 ' assigned) Hubsteueranordnung 13 ' of the dual-fuel fuel injector 1' , which works on the principle of the double-acting cylinder, divides volume variable from each other. To a respective control room 9 ' . 1 1' Here is a control line 15 ' . 17 ' led, which control lines 15 ' . 17 ' furthermore depending on a switching valve 19 ' either with a pressure sink 21 ' or a pressure source 23 ' are connectable (the control lines 15 ' . 17 ' the plurality of Hubsteueranordnungen 13 ' For example, they can be brought together, for example, to a single changeover valve 19 ' ).

About the pressure source 23 ' - A fuel injection system - is high pressurized control fluid to a respective - valve position dependent - loaded connected control room 9 ' respectively. 11 ' can be supplied to the pressure sink 21 ' (Low pressure) is control fluid from the control valve depending on the valve position dependent relieving connected control room 11 ' respectively. 9 ' absteuerbar. With this Hubsteueranordnung 13 ' can - depending on the position of the switching valve 19 ' - a control room 9 ' respectively. 11 ' be burdened, the other 11 ' respectively. 9 ' this relieved and vice versa, hence the fuel gas nozzle valve member 5 ' be controlled in open or closed position.

The dual-fuel fuel injector 1' The prior art further includes a hold-down assembly 25 ' (per fuel gas nozzle valve member 5 ' ), via which the fuel gas nozzle valve member 5 ' with a closing force (arrow arrow A ' ) is charged. The hold-down arrangement 25 ' is by means of a stilt element 27 ' formed, which is an intermediate plate 29 ' , remote from the nozzle body 3 ' arranged, with a bolt-shaped section 31 ' passes, which in this case in a correspondence recording (axial bore) of the intermediate plate 29 ' is guided.

A spring plate 33 ' of the stilts 27 ' is in a spring room 35 ' taken, which to the intermediate plate 29 ' adjacent in a further, nozzle-distant housing element 37 ' of the dual-fuel fuel injector 1' is formed. The spring chamber 35 ' this acts simultaneously as a fuel gas buffer or passage memory, including one end (nozzle distant) a fuel gas supply line 39 ' (High pressure) to the buffer (spring space 35 ' ) leads, at the other end (near the nozzle) a section 39a ' the fuel gas supply line 39 ' proceeding from the buffer to a nozzle space 41 ' (in 1 not explicitly shown) leads.

In the spring room 35 ' or fuel gas buffer is still a compression spring 43 ' received, by means of which the closing force A ' - indirectly via the stilts 27 ' - On the fuel gas nozzle valve member 5 ' is exercised. Here is the compression spring 43 ' one end against the nozzle-distant end face 45 ' of the spring chamber 35 ' crowded, at the other end against the spring plate 33 ' , The compression spring 43 ' is designed as a wire-based coil spring or wire spring and builds obviously relatively long, ie with a dimension L1 (In this case referred to the closed state of the fuel gas nozzle valve member shown 5 ' ). Due to the considerable size of the coil spring 43 ' is their accommodation in the intermediate plate 29 ' made impossible, so that the fuel gas - the thus considerably cramped space owed - forced by the spring chamber 35 ' must be led. As a result, a barrier fluid seal 47 ' on the stilts 27 ' in the intermediate plate 29 ' required, but from which an unintentional Sperrfluideintrag (via the Kriechspalt along the stilt guide) in the fuel gas (in the spring chamber 35 ' ) results. Furthermore, it comes with this solution to unintentional turbulence in the fuel gas buffer (spring chamber 35 ' ), in particular the turns of the spiral spring 43 ' owing so that the intended homogeneous flow of the downstream nozzle orifices 49 ' (in 1 not explicitly illustrated) is not guaranteed.

2 now shows in a broken and partially cut view of a dual-fuel fuel injector 1 according to the invention. As in the prior art discussed above, the dual-fuel fuel injector 1 a number of lift-controllable fuel gas nozzle valve members 5 on, generally at least one fuel gas nozzle valve member 5 , preferably three or more fuel gas nozzle valve members 5 which are each provided in particular as a fuel gas nozzle needle. Each fuel gas nozzle valve member 5 is at least one nozzle opening 49 a nozzle arrangement 51 of the dual-fuel fuel injector 1 associated, which via the respective fuel gas nozzle valve member 5 is selectively auf- and zuusteuerbar (depending on a stroke position of the same). The nozzle openings are preferred 49 the nozzle assembly 51 arranged so that the best possible 360 ° coverage is achieved in the context of Ausdüsung.

Received and guided is a respective fuel gas nozzle valve member 5 in a correspondence admission 53 in a nozzle body 3 of the dual-fuel fuel injector 1 , preferably designed as axial bore. In the illustrated dual-fuel fuel injector 1 surround the fuel gas nozzle valve members 5 eg also a - centrally in the nozzle body 3 arranged - liquid fuel nozzle valve member 55 , eg in a triangular formation or along a circular line (viewed in the circumferential direction) about the same. The liquid fuel nozzle valve member 55 is independent of the fuel gas nozzle valve members 5 controllable, eg indirectly hydraulically via a control arrangement with a pilot valve (not shown), a control room 57 (further comprising a needle guide sleeve 59 and a nozzle spring 61 ).

The dual-fuel fuel injector 1 further comprises a Hubsteueranordnung 13 each fuel gas nozzle valve member 5 , which Hubsteueranordnung 13 works hydraulically on the principle of a double-acting cylinder, in particular as explained above for the prior art. Here, a nozzle-distant end portion of a respective fuel gas nozzle valve member forms 5 a (acting as a piston) piston section 7 the Hubsteueranordnung 13 , which is a nozzle-distant control room 9 and a nearer control room 11 each also the Hubsteueranordnung 13 volume variable from each other. To every control room 9 . 11 each leads a control line 15 respectively. 17 , which - as in the prior art - to a switching valve according to 19 '(servo or pilot valve), in particular a 4/2-way valve (in 2 not shown), for the alternate loading and unloading with a pressure source 23 ' (pressurized control fluid) or a pressure sink 21 ' ( Leakage side or low pressure side) can be connected. The switching valve may preferably be part of the dual-fuel fuel injector 1 or even separately, for example, be arranged externally.

The dual-fuel fuel injector 1 shows how 2 This illustrates, as in the prior art, a hold-down arrangement 25 each fuel gas nozzle valve member 5 on, in which - in contrast to the prior art - the respective hold-down arrangement 25 but now has a "Machined Spring" 63, ie executed as a compression spring, by means of which the respective hold-down arrangement 25 a respective fuel gas nozzle valve member 5 in the closing direction (arrow direction arrow A ) charged. In that regard, in the dual-fuel fuel injector 1 according to the invention, a respective fuel gas nozzle valve member 5 each with a hold-down arrangement 25 with a "Machined Spring" 63 in the closing direction A loaded.

The one with the proposed dual-fuel fuel injector 1 used "Machined Springs" 63 have compared to the previously provided wire-based or wire-wound coil springs 43 ' - For equivalent clamping force application - advantageously shorter dimension L2 (refer to the illustrated closed state of the fuel gas nozzle valve member 5 ), ie a longitudinal dimension L2 , so that - in the closed state of the fuel gas nozzle valve member shown 5 - An aspect ratio L2: L1 of about 0.66, ie a shortening by one third of the former spring length can be realized (in general, this ratio can also be approximately for the relaxed state of the springs 43 ' and 65 be valid).

These thus much shorter "Machined Springs" 63 now make it advantageous, the same entirely in the intermediate plate 29 to be able to accommodate so that space for a fuel gas supply line 39 is now so sufficiently available that the fuel gas no longer by a spring chamber 35 ' as must be done in the art, but with generously dimensioned fuel gas supply lines 39 to a nozzle space 41 or to the nozzle arrangement 51 is feasible. As a result, the associated disadvantages, see above in the prior art or as explained above, advantageously avoided.

As 2 this also illustrates a respective spring chamber 35 in which a "Machined Spring" 63 is recorded, designed as a correspondence cavity, so that the "Mashined Spring" 63 - At least over a section - circumferentially feasible, thus buckling is thereby avoided. The respective spring chamber 35 is preferably as a blind hole in the intermediate plate 29 formed, wherein the blind bore is arranged so that with joining of the intermediate plate 29 and nozzle body 3 the blind bore or the spring chamber 35 coaxial with the receptacle 53 the fuel gas nozzle valve member 5 is aligned. In this case, then the spring chamber 35 and the nozzle-distant end of the recording 53 together the nozzle-distant control room 9 the Hubsteueranordnung 13 form, ie in the sense of a coherent volume.

The hold-down arrangement 25 according to the in 2 illustrated embodiment further comprises a stilt element 27 which has a nozzle-distal, bolt-shaped or pin-shaped section 65 which on the inside on the windings of the "Machined Spring" 63 radially or peripherally in abutment, so that also a possible Auknicken the "Machined Spring" 63 is effectively avoided on the inside. A nozzle-near end section "the Machined Spring" 63 is against a spring plate 33 of the stilts 27 crowded, waving from the spring plate 33 towards the fuel gas nozzle valve member 5 protruding engagement section 67 of the stilts 27 (in the form of a very short appendix) which is created by means of "Machined Spring" 63 generated closing force on the fuel gas nozzle valve member 5 , That is, at a nozzle distal end portion thereof or the piston member 7 able to exercise.

Based on 3 Now, further details of the proposed dual-fuel fuel injector 1 explained in more detail.

As 3 this illustrated, can be made of the solid worked, in particular machined from the solid spring 63 ie the "Machined Spring" 63 , advantageous with contact surfaces 69 be configured at the nozzle distant and the nozzle closer end, ie at their axially opposite ends of the plant 69 , which each extend as a ring surface completely flat and level same, so that so - in contrast to spiral fields 43 ' - A support, thus also a force, homogeneous over the entire circumference of the spring 63 can be done. Advantageously, this is to the effect that the force distribution can thus take place parallel to the central axis, but not a tilting moment is caused by a selective application of force, as with previously usual spiral springs 43 ' the case may be. To increase the precision of parallelism, the spring can 63 in the form of "Machined Spring" this also be executed with more than one thread, ie more stable.

Like this also by the 3 can be shown in the spring chamber 35 , in particular nozzle-remote in the same, furthermore an adjusting element 71 be included, for example, between the nozzle-distant end of the "Machined Spring" 63 and the adjacent end wall 45 of the spring chamber. The adjustment element 71 may be an annular disc, wherein the choice of the thickness of the same one Biasing force is set, thus the closing force on the fuel gas nozzle valve member 5 can be influenced in an intentional way.

3 next to it shows the connection end 73 the control line 15 at the nozzle remote control room 9 , which groove-shaped to the control room 9 can be performed, for example, as a groove in the end face of the nozzle body 3 formed and by means of the intermediate plate 29 can be capped (intermediate plate 29 and nozzle body 3 are here with a clamping nut 75 tense, s. 2 ). As in the presently disclosed embodiment, in which the control room 9 together with the spring chamber 35 is formed, the spring chamber 35 Also, with control fluid is applied, the wall of the spring chamber 35 Over at least a portion of an axially extending (eg groove-shaped) recess 77 by means of which at an opening stroke of the fuel gas nozzle valve member 5 and concomitant reduction in volume of the nozzle-remote control room 9 including spring chamber 35 the control fluid from the spring chamber 35 can be displaced, ie via the communicatively connected control line 15 ,

4 illustrates the intermediate plate 29 of the dual-fuel fuel injector 1 in a view of the nozzle closer side or bottom, wherein the spring chambers 35 including the formed in the walls, axially extending recesses 77 are shown for the displacement of control fluid. It is apparent in this embodiment, per spring chamber 35 for example two axial depressions 77 to build. In the middle of the triangular formation of the spring chambers 35 are still sections of liquid fuel supply lines 79 now shown, now also generously dimensioned fuel gas supply lines 39 in sections through the intermediate plate 29 are feasible, which are now advantageously unobstructed pictorial. Also shown are, for example, control line sections of the control lines 17 as well as through the intermediate plate 29 guided sections of the fuel gas supply lines 39 ,

LIST OF REFERENCE NUMBERS

1, 1 '

Dual-fuel fuel injector

3, 3 '

nozzle body

5, 5 '

Fuel gas nozzle valve member

7, 7 '

piston section

9, 9 '

Control room (jet-distant)

11, 11 '

Control room (near the nozzle)

13, 13 '

Hubsteueranordnung

15, 15 '

control line

17, 17 '

control line

19 '

switching valve

21 '

pressure sink

23 '

pressure source

25, 25 '

Hold down assembly

27, 27 '

stilts element

29, 29 '

intermediate plate

31 '

Bolt-shaped section

33, 33 '

spring plate

35, 35 '

spring chamber

37, 37 '

another housing element

39, 39 '

Fuel gas supply line

39a, 39a '

section

41, 41 '

nozzle chamber

43 '

Wire-based compression spring (spiral spring)

45, 45 '

nozzle-distant end face

47 '

Blocking fluid seal

49, 49 '

nozzle opening

51

nozzle assembly

53

correspondence recording

55

Liquid fuel nozzle valve member

57

control room

59

Needle guide sleeve

61

nozzle spring

63

Machined Spring

65

Pin or pin-shaped section

67

engaging portion

69

contact surface

71

Adjusting element

73

terminal end

75

locknut

77

deepening

79

Liquid fuel supply line

A, A '

Closing force direction

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102015016034 B3 [0002]

Claims (10)

Dual-fuel fuel injector (1), comprising: - at least one lift-controllable fuel gas nozzle valve member (5) for the selective opening and closing of at least one nozzle opening (49) of a nozzle arrangement (51) of the dual-fuel fuel injector (1), a Hubsteueranordnung (13) per fuel gas nozzle valve member (5) which Hubsteueranordnung (13) works hydraulically according to the principle of a double-acting cylinder, characterized in that - a respective fuel gas nozzle valve member (5) via one hold-down assembly (25) with a "Machined Spring" (63) is loaded in the closing direction (A). Dual fuel fuel injector (1) after Claim 1 , characterized in that - the dual-fuel fuel injector (1) has a plurality of Hubsteueranordnung via a Hubsteueranordnung (13) Hubsteuerbaren fuel gas nozzle valve members (5) for the selective opening and closing of nozzle openings (49) of an associated nozzle assembly (51) of the dual-fuel fuel injector (1), wherein a respective fuel gas nozzle valve member (5) via one hold-down assembly (25) with a "Machined Spring" (63) in the closing direction (A) is loaded. Dual-fuel fuel injector (1) according to one of the preceding claims, characterized in that - together with a spring chamber (35) of the hold-down arrangement (25), in which the "Machined Spring" (63) is accommodated, a control space (9) remote from the nozzle ) of the Hubsteueranordnung (13) is formed. Dual fuel fuel injector (1) after Claim 3 , characterized in that - the spring chamber (35) all in an intermediate plate (29) of the dual-fuel fuel injector (1) is formed. Dual fuel fuel injector (1) after Claim 4 , characterized in that - the respective fuel gas nozzle valve member (5) all in a nozzle body (3) of the dual-fuel fuel injector (1) is accommodated, which by means of the intermediate plate (29) is capped. Dual-fuel fuel injector (1) according to any one of the preceding claims, characterized in that - the respective hold-down assembly (25) has a stilt element (27) which via the "Machined Spring" (63) exerting a force in the closing direction (A) is urged against a nozzle distal end portion (7) of the fuel gas nozzle valve member (5). Dual Fuel Fuel Injector (1) according to one of the Claims 2 to 6 characterized in that - said plurality of fuel gas nozzle valve members (5) are circumferentially spaced apart along a circular line surrounding a central nozzle needle (55) for delivery of another fuel. Dual-dual-fuel injector (1) according to any one of the preceding claims, characterized in that - a respective "Machined Spring" (63) is a catchy, double-flighted or multi-speed spring. Dual-fuel fuel injector (1) according to one of the preceding claims, characterized in that - the closing force of at least one "machined spring" (63) is additionally set with an adjusting element (71) via which the "machined spring" (63) is biased. Internal combustion engine, in particular with a fuel gas common rail injection system, characterized in that - the internal combustion engine has at least one dual-fuel fuel injector (1) according to one of the preceding claims.

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