DE102018209101A1 - Injector and internal combustion engine with adaptive injection behavior - Google Patents

Abstract

The present invention relates to an injector for injecting fuel, in particular directly into a combustion chamber of an internal combustion engine, comprising a one-piece closing element (2), a valve body (3), a first injection nozzle arrangement (101) in the valve body (3) with a plurality of first injection holes (31), a second spray hole assembly (102) in the valve body (3) having at least a second spray hole (32), wherein the first spray hole arrangement (101) of the second spray hole assembly (102) in the axial direction of the injector offset by a predetermined distance (A) is a first sealing seat (4) between the closing element (2) and the valve body (3), and a second sealing seat (5) between the closing element (2) and the valve body (3), which in the axial direction of the injector between the first and second injection port arrangement (101, 102) is arranged, wherein the second sealing seat (5) in the axial direction of a cylindrical sealing surface with a predetermined Lä L (L), in order to achieve a stepped injection of the fuel in the opening case of the injector, and wherein the first injection nozzle arrangement (101) equal to many or more injection holes than the second injection nozzle arrangement (102).

Description

State of the art

The present invention relates to an injector for the direct injection of fuel into a combustion chamber and to an internal combustion engine having such an injector, in particular for carrying out a homogeneous combustion process. Furthermore, the present invention relates to the use of an injector according to the invention and various methods for operating an internal combustion engine.

Injectors for internal combustion engines are known from the prior art in different embodiments. In Otto internal combustion engines, in which there are lower injection pressures compared to diesel internal combustion engines, injectors are known with a plurality of injection holes, which are usually in a plane perpendicular to a central axis of the injector. In this case, injection angles of the individual injection holes can be varied in order to produce different spray patterns. From the WO 2006/040283 A1 , of the DE 10 2015 223 437 or the DE 10 2010 063 355 A1 In each case, an injector for a diesel internal combustion engine is known in which injection holes are arranged one above the other in two spray-hole rows. In this case, only one sealing seat is present between a needle and a valve body. When the needle is opened from the sealing seat, fuel is injected through the two spray-hole rows. In this case, there is always a pairwise injection of fuel through the superposition arrangement of the injection holes of the two injection hole rows. Due to different angles of the injection holes of the two spray-hole rows, a higher penetration depth of the fuel spray jets into the highly compressed combustion chamber of the diesel internal combustion engine can be achieved. As a result, advantages can be obtained in the diesel combustion.

For conventional Otto engine combustion methods, an increased penetration depth is not expedient due to the comparatively lower back pressure, in particular during the intake stroke injection. In the application for gasoline engines, the goal is to avoid by a corresponding spray breakup and its interaction with the charge movement, wall contact of injected fuel and to achieve a homogeneous mixture composition as possible.

Disclosure of the invention

The injector according to the invention of an internal combustion engine for injecting fuel with the features of claim 1 has the advantage that a combustion process of the internal combustion engine can be significantly improved, in particular less gaseous raw emissions (HC, CO and NOx raw emissions) as well as particulate emissions (Soot) can be achieved. This is inventively achieved in that the injector comprises a one-piece closing element and a valve body, are formed in which injection holes. Here, a first injection nozzle arrangement is provided in the valve body with a plurality of first injection holes and a second injection nozzle arrangement is provided in the valve body with at least one second injection hole. In this case, a number of spray holes of the first spray hole arrangement is equal to or greater than a number of spray holes of the second spray hole arrangement. The special arrangement of the injection holes is such that the first injection nozzle arrangement is offset from the second injection nozzle arrangement in the axial direction of the injector by a distance A. Furthermore, a first sealing seat and a second sealing seat is formed between the one-piece closing element and the valve body. In this case, the second sealing seat is arranged in the axial direction of the injector between the first spray-hole arrangement and the second spray-hole arrangement. The second sealing seat has in the axial direction of the injector on a cylindrical sealing surface with a predetermined length in order to achieve a stepped injection of the fuel in the opening case of the valve. As a result of the cylindrical sealing surface on the second sealing seat, when opening the closing element, first the first spray-hole arrangement is released, so that fuel can be injected into a combustion space via the injection holes of the first injection-molding arrangement and after the predetermined length at the second sealing seat has been replaced by the opening closing element, the injection holes become the second spray hole arrangement released and is injected via the injection holes of the second spray hole arrangement in the combustion chamber. Thus, a stepped injection can be achieved, wherein all the injection holes are preferably released only after a predefined stroke, in particular a full stroke of the one-piece closing element.

It should be noted that in the closed state, the first sealing seat completely seals. In the opening case, the second sealing seat is not quite tight due to the cylindrical guide. Since an axial length of the second sealing seat becomes smaller and smaller as the opening stroke continues, the second sealing seat acts like a variable throttle. Thus, the second sealing seat may also be referred to as a variable throttle seat. In the opening case leakage over the second sealing seat with increasing opening travel is always greater until then no radial overlap between the valve body and the cylindrical guide of the second sealing seat is more present and the second sealing seat opens completely. Thus, by means of the injector according to the invention in Otto engine combustion method simple way in partial load operation only by opening the first spray hole arrangement and a full load operation by opening the first and second spray hole arrangement are made possible. Up to now, there has always been a conflict of objectives in the state of the art in Otto engine combustion processes between a design of the combustion process for partial load and full load. This can be solved according to the invention by the possibility of the stepped injection. Here, the first injection nozzle arrangement is optimized with a plurality of spray holes for a partial load of the internal combustion engine and the second injection nozzle arrangement is then optimized for higher loads or full load operating point of the gasoline engine. Another major advantage of the invention is that it is now possible to provide in the first spray hole arrangement special injection injection ports, which supply the fuel to the spark plug or into a region close to the spark plug. Here, an uncompromising interpretation of such a Zünd-spray hole can be made because the additional amount of fuel required over the other spray holes of the first spray hole arrangement at partial load and higher load demand can be injected as a partial load or full load in addition to the second spray hole arrangement. This results in the possibility to design the injection process so that the combustion is positively influenced and thus the efficiency of the internal combustion engine can be improved. Thus, the injector according to the invention can realize two optimized spray designs for part load and full load or higher load requirements.

It should be noted that the partial load range preferably ranges up to a range of 70% of a maximum load requirement of the internal combustion engine. In the range of 70% to 100% then the full load or higher load requirement is given.

The dependent claims show preferred developments of the invention.

Preferably, a maximum flow rate of fuel through the injection holes of the first injection pattern is in a range of 30% to 40% of a total flow of the fuel through the injection holes of the first and second spray holes. In this way it can be ensured that only relatively small injected fuel masses are injected at partial load in order to ensure a good mixture formation in the combustion chamber.

More preferably, all spray cones generated by the first spray hole arrangement are farther from a central axis of the injector than all the spray cones generated by the second spray hole arrangement. In this case, it is particularly preferred if, up to a distance of at least 30 mm from an injector tip, this requirement that the spray cones of the first spray-hole arrangement run farther outward than the spray cones of the second spray-hole arrangement is fulfilled. In a region farther than 30 mm from the injector tip, the spray cones can then be cut or mixed.

More preferably, at least one spray hole of the first spray hole arrangement is arranged such that a formation of a spray cone is directed through the spray hole of the first spray hole arrangement in the direction of a spark plug and / or adjacent to a spark plug. This at least one spray hole can also be referred to as an ignition spray hole and can be optimally designed for the formation of an ignitable mixture in the region of the spark plug. In this case, two ignition-injection holes are particularly preferably provided in the first spray-hole arrangement. The spray cone of the two ignition-injection holes are such that in the installed state in an internal combustion engine, a spark plug is exactly between the two generated spray cones of the ignition spray holes.

A particularly low-emission combustion method can be achieved if an injection direction of the injection holes of the first and second injection nozzle arrangement is such that each injection direction of the injection holes in a plan view in the axial direction of the injector is different to the spray pattern. In other words, starting from a center line of the injector, the respective radial main direction of the spray cones of the injection holes formed is different, so that preferably there is no overlap of the spray cones of all spray holes. More preferably, all the injection holes of the first and second spray hole arrangement are directed at an acute angle to the central axis of the injector. Particularly preferably, the acute angle of pairwise spray holes is the same.

In order to achieve a uniform distribution of the fuel in the combustion chamber, preferably the injection holes of the first spray hole arrangement in a first plane E1 arranged perpendicular to a central axis of the injector and the second injection holes of the second spray hole arrangement in a second plane E2 arranged perpendicular to the central axis of the injector. The first level is positioned away from the second level by the distance A.

The first plane and the second plane are defined in such a way that all centers of the first injection holes are at the entry location of the first injection holes in the first plane and all centers of the second injection holes are at the entry location of the second injection holes in the second plane.

Preferably, the first sealing seat is a tapered sealing seat, in particular a conical sealing seat.

More preferably, the injector is an inwardly opening injector. That is, the closing member of the injector is retreated toward the injector interior to release the injection ports for the injection of fuel.

Furthermore, the present invention relates to an internal combustion engine with an injector according to the invention.

Preferably, the internal combustion engine comprises a spark plug. More preferably, the spray holes of the first spray hole arrangement are arranged such that at least one spray cone of the injection holes of the first spray hole arrangement is directed towards the spark plug or directly to the spark plug.

Preferably, the injector and / or the spark plug is arranged centrally between intake and exhaust valves in the cylinder head. Preferably, a central axis of the injector is parallel, preferably identical, with a central axis of the cylinder in the combustion chamber.

Further preferably, the internal combustion engine further comprises a control unit which is configured to open at a partial load request of the internal combustion engine only the first spray hole arrangement and at a load request greater than the partial load request, in particular a full load request, the internal combustion engine to open both the first and the second spray hole arrangement. As a result, an optimized injection can be achieved both for partial load and for full load. It should be noted that according to the invention under partial load a load requirement in a range of less than or equal to 70% of the maximum load of the internal combustion engine is understood. Full load is therefore an area greater than 70% of the load requirement.

More preferably, the control unit of the internal combustion engine is set up to carry out an injection at an air ratio of λ = 1, both in partial load operation and in full load operation shortly after a charge change upper dead center (LOT). The injection is preferably carried out under a high pressure of greater than 2000 × 10 ⁵ Pa. This leaves more time for mixture formation and the high system pressure also has a positive effect on mixture formation.

More preferably, the control unit is configured to carry out various lean combustion processes. These include u.a. homogeneous compression ignition (HCCI Homogeneous Charge Compression Ignition, with and without ignition assist), stratified combustion as well as homogeneous lean burn processes, which are characterized by injection of a minimum amount in the compression stroke. The lean burn process can be carried out here with auto-ignition or alternatively with ignition assistance. The air ratio Ä is preferably much greater than 1. For example, in the HCCI combustion process, a homogeneous mixture due to a very high compression burn at the same time in the entire combustion chamber. This can be done either a self-ignition of the homogeneous mixture or alternatively, a spark ignition with a spark plug. Preferably, the HCCI combustion process is realized in the partial load range with auto-ignition and in a load range greater than the partial load range to the absolute full load with spark ignition.

According to a further preferred embodiment, the control unit of the internal combustion engine is configured to carry out a pilot injection and optionally one or more main injections both in partial load and in full load. In this case, a partial injection is preferably carried out shortly after the charge cycle top dead center (LOT), a pilot injection and executed shortly before an ignition top dead center (ZOT) one or more main injection (s). At full load is preferably shortly after the top charge top dead center (LOT) injection via the first and second spray hole arrangement executed and shortly before the ignition top dead center (ZOT) one or more additional ignition assisting injection (s) only via the first spray hole arrangement ,

Particularly preferably, a multiple injection takes place in the suction stroke and / or in the compression stroke.

Furthermore, the present invention relates to the use of the injector according to the invention in an internal combustion engine, in particular an Otto internal combustion engine. In this case, the internal combustion engine preferably has injection pressures of 200 to 2000 × 10 ⁵ Pa, in particular 300 to 350 × 10 ⁵ Pa.

list of figures

Hereinafter, embodiments of the invention will be described in detail with reference to the accompanying drawings. In the drawing is:

• 1 a schematic sectional view of an injector according to a first embodiment of the invention with an enlarged detail,
• 2 a schematic sectional view of an internal combustion engine with the injector of 1 .
• 3 a schematic partial sectional view of the internal combustion engine of 2 , wherein only a first spray hole arrangement is released,
• 4 a plan view of the spray image of the injector of 3 with only opened first spray hole arrangement,
• 5 a partial sectional view of the injector of 2 with open first and second spray hole arrangement,
• 6 a top view of the spray image of the injector of 5 with open first and second spray hole arrangement,
• 7 a schematic representation of the position of the spray lobes in the combustion chamber at a distance of 30 mm from an outermost Injektorspitze according to the line VII-VII of 2 .
• 8th a schematic diagram showing a combustion method of the internal combustion engine of 2 at partial load with the injected fuel quantity M over a crank angle K with spark ignition,
• 9 a schematic diagram showing a combustion method of the internal combustion engine of 2 at full load with the injected fuel quantity M over a crank angle K with spark ignition,
• 10 a schematic diagram showing a HCCI combustion method at partial load,
• 11 a schematic diagram showing a HCCI combustion process at full load,
• 12 a schematic diagram showing an HCCI combustion method at partial load according to 10 with additional compression stroke injection and spark ignition,
• 13 a schematic diagram showing an HCCI combustion method of the internal combustion engine according to 11 with additional compression stroke injection and spark ignition,
• 14 a schematic diagram showing a combustion method with pre-injection and main injection at partial load with auto-ignition, and
• 15 a schematic diagram showing a combustion method with pre-injection and main injection at full load with auto-ignition.

Preferred embodiments of the invention

The following is with reference to the 1 to 9 an injector 1 according to a first preferred embodiment of the invention described in detail. How out 1 and the detail enlargement of 1 can be seen, includes the injector 1 a one-piece closure element 2 , which is provided in the form of a needle.

The injector 1 further comprises a valve body 3 , wherein between the one-piece closing element 2 and the valve body 3 a first sealing seat 4 and a second sealing seat 5 is trained. How out 1 can be seen, are the first and second sealing seat 4 . 5 in the axial direction XX of the injector spaced by a distance.

The first sealing seat 4 is a conical sealing seat between closing element and valve body and the second sealing seat 5 is a cylindrical sealing seat between closing element and valve body.

The injector 1 further includes a first spray hole arrangement 101 with first spray holes 31 and a second spray hole arrangement 102 with second spray holes 32 , In the 1 and 2 are schematically only one injection hole of the two spray hole arrangements 101 . 102 located. As in detail, however, from the 3 and 4 5 and 6, includes the first spray hole arrangement 101 this embodiment five spray holes 31 , where as in 4 shown, five spray clubs 11 . 12 . 13 . 14 . 15 be generated. Through the spray holes 32 the second injection hole arrangement 102 be like in the 5 and 6 shown, five more spray lobes 21 . 22 . 23 . 24 . 25 generated. Thus, the number of injection holes of the first and second spray hole arrangement is the same.

How out 1 it can be seen, are the injection holes 31 the first injection hole arrangement 101 in a first level E1 arranged. The spray holes 32 the second injection hole arrangement 102 are in a second level E2 arranged. How out 1 it can be seen, is the first spray hole arrangement 101 thereby by the distance A from the second spray hole arrangement 102 in the direction of the central axis XX spaced apart from the injector. The first and second levels E1 and E2 lie in each case in centers of the first and second injection holes on an inner side of the valve body 3 ,

How further from the 4 and 6 it can be seen, the injection directions of the injection holes of the first and second spray hole arrangement 101 and 102 each different in the circumferential direction. This results in only partial overlaps of the spray lobes 11 . 12 . 13 . 14 . 15 the first spray hole arrangement and the spray lobes 21 . 22 . 23 . 24 . 25 the second injection hole arrangement 102 in top view of the spray image.

As further from the enlargement of 1 can be seen, the second sealing seat 5 in the direction of the central axis XX an axial length L on. Furthermore, the second sealing seat 5 as a cylindrical sealing surface in the direction of the central axis XX provided so that when opening the closing element 2 the closing element immediately from the first sealing seat 4 . which is designed as a tapered, in particular conical sealing seat lifts, but first still on the cylindrical second sealing seat 5 remains and seals there. Here, the cylindrical second sealing seat acts 5 as a cylindrical guide for the one-piece closing element 2 , Here is the second sealing seat 5 not completely tight, but some leakage occurs on the cylindrical inner circumference of the valve body 3 on, leaving the second sealing seat 5 is a kind of variable throttle seat.

As a result, the flow path for the fuel at first only for the first spray hole arrangement 101 with the first spray holes 31 Approved. Only after covering a predetermined path of the closing element is the second sealing seat 5 fully released and fuel also flows through the spray holes 32 the second injection hole arrangement 102 , Only then does this result in 6 shown star-shaped spray pattern with all spray lobes of the first and second spray hole arrangement. As long as a seal on the second sealing seat 5 takes place, this results in 4 Spray picture shown only with the spray lobes 11 . 12 . 13 . 14 . 15 because only fuel through the spray holes 31 the first injection hole arrangement 101 in the combustion chamber 9 is injected. The release of the second spray holes 32 can choose about an axial length of the tip of the sealing seat 5 complementary cylindrical end portion of the closing element 2 be set.

How out 2 is apparent, is the injector 1 on the internal combustion engine 100 directly to a combustion chamber 9 arranged. Furthermore, schematically are a piston 7 and a cylinder 8th and an inlet valve 35 and an exhaust valve 36 shown.

Here, the injector points 1 a central mounting position, in which the central axis XX of the injector in parallel, preferably also identical, with a central axis YY of the cylinder is.

How farther 2 can be seen, includes the internal combustion engine 100 an ignition device in the form of a spark plug 6 , The spark plug 6 is adjacent to the injector 1 arranged. How out 2 and especially from 4 it can be seen, is the spark plug 6 arranged such that when injected through the injection holes 31 the first injection hole arrangement 101 the two generated spray lobes 11 . 12 towards the spark plug 6 are directed. How farther 4 it can be seen, is an angle a, in which the spray lobes expand, smaller than 90 °. Here is the spark plug 6 exactly between the two spray lobes 11 . 12 arranged. This will in the immediate vicinity of the spark plug 6 reaches an ignitable mixture, which passes through the spark plug 6 is flammable, or a mixture that supports the ignition mechanisms.

For better illustration of the spray hole arrangements, the cuts in the 3 and 5 along the lines DD respectively. EE , as in 3 and 6 indicated, executed.

By the formation of the first and second spray hole arrangement 101 and 102 each with a plurality of spray holes, it is thus possible that the first spray hole arrangement 101 is designed for a partial load range of the internal combustion engine and the second spray hole arrangement 102 is designed for a full load range of the internal combustion engine. In part load operation, we thus the closing element 2 open only so far that fuel, as in 3 and 4 shown, can flow only through the first spray hole arrangement and a partial load operation of the internal combustion engine is possible. In full load operation, the closing element 2 then fully open, so that, as in the 5 and 6 shown an injection of fuel through both the first and the second spray hole arrangement 101 and 102 he follows.

As in 7 shown is the position of the spray lobes 11 . 12 . 13 . 14 . 15 the first spray hole arrangement at a distance of 30 mm from an outermost injector tip 30 in the combustion chamber 9 in such a way that these spray lobes 11 . 12 . 13 . 14 . 15 radially farther away from a central axis XX of the injector are the spray lobes 21 . 22 . 23 . 24 . 25 the second injection hole arrangement 102 , 7 Here is a section through the combustion chamber at full load, in which fuel is injected via both the first and the second spray hole arrangement.

Thus, the arrangement of the spray holes two independent injection hole circles for the first and second spray hole arrangement. In particular, it can also be prevented that individual spray lobes are also at full load, i. with the injector fully open, interact.

A flow through the spray holes 31 the first injection hole arrangement 101 lies in a range of 30% to 40% of a maximum possible flow. That is through the spray holes 32 the second injection hole arrangement 102 then 60% to 70% of the fuel will flow accordingly when full load conditions prevail.

Thus, in load dependency, a control unit may control the engine so that either only the first spray hole arrangement 101 is released at part load or both Spritzlochanordnungen 101 . 102 be released together at very high loads or full load. Furthermore, two injection holes of the first spray hole arrangement 101 designed such that their spray lobes 11 . 12 towards the spark plug 6 are aligned. This can ensure a safe ignition of the Mixture in the combustion chamber 9 be enabled. Furthermore, the two spray holes, which the spray lobes 11 and 12 generate, be designed as so-called Zünd-injection holes and are designed precisely to the ignitability. Thus, the flaming conditions can be significantly improved and an initial flame propagation can be controlled selectively. In addition, there is the possibility to make the injection process such that the combustion is positively influenced and thus the efficiency of the internal combustion engine can be improved. This is the case both at partial load and at full load.

Thus, the present invention can solve the problem that a compromise is required on the jet design of the injector either in favor of the partial load or in favor of the full load. Due to the possibility of two-stage injection, a spray hole series for partial loads and a spray hole series for high loads or full load can be designed.

By the possible stepped injection of fuel, different combustion methods can now be realized by means of the injector according to the invention.

8th shows an example of a diagram representing the injected amount of fuel M over the crank angle K. In 8th means the abbreviation OT "top dead center", where in 8th A distinction is made between the LOT (charge change upper dead center) and the ZOT (ignition upper dead center). UT means "bottom dead center".

8th in this case shows a partial load operation of the internal combustion engine. For clarification is in 8th a spray picture S1 plotted, in which only the first spray hole arrangement 101 is open. This results in the five spray cone 11 . 12 . 13 . 14 . 15 , An air ratio λ is selected equal to 1. The second sealing seat 5 of the injector 1 this is still closed. This is a first amount of fuel M1 injected shortly after the charge cycle top dead center (LOT). The mixture is then flashed Z ignited.

In a preferred further method based on 8th and 9 It is also conceivable that at partial load or high load or full load, the fuel is injected additionally or exclusively in the compression stroke (see M1 * and M1 * '). Here also a multiple injection can be realized in each case.

In contrast, in the case of 9 a full load injection shown in the diagram shown in the fuel both via the first and the second spray hole arrangement 101 and 102 is injected. This results in a significantly larger amount of fuel M1 , which is injected shortly after the charge cycle top dead center (LOT). A spark ignition Z occurs shortly before the ignition top dead center (ZOT).

The 10 to 15 describe the use of the device in various lean burn processes.

The 10 and 11 show a preferred HCCI combustion process with the injector according to the invention. For an HCCI combustion method, the injector is particularly preferably suitable, since this is a very good homogenization due to the specific design feasible. 10 shows here the part-load operation, in which only the first spray hole arrangement 101 is open and 11 the full load operation, in which the first and second spray hole arrangement 101 and 102 are open. By an injection pressure of up to 2000 × 10 ⁵ Pa, the fuel can be injected in a very short time. Alternatively, as in the 10 and 11 indicated by the parenthesis in the ignition arrow, if necessary, a spark plug may be provided and an ignition assistance shortly before the ignition top dead center (ZOT) done. There, how from the 10 and 11 It can be seen, only one suction stroke injection takes place, significantly more time remains for a homogeneous mixture formation in the combustion chamber with corresponding advantages in terms of combustion, consumption and exhaust emissions.

The injection pattern off 10 and 11 At the same time, they are also the basis for a homogeneous lean burn process initiated by spark ignition and characterized by a deflagrative flame spread / mixture composition. In this case, a multiple injection M1 'is preferably also possible.

In the 12 and 13 an alternative HCCI combustion process is shown. In contrast to the embodiment in the 10 and 11 However, here is additionally provided a compression stroke injection. 12 again shows the partial load condition, with a first intake stroke injection (Spraybild S1 ) and a second compression stroke injection (Spraybild S2 ) takes place only when the injector is partially open. At full load ( 13 ), a suction stroke injection takes place with the injector fully open (spray pattern S1 from 13 ) and a compression stroke injection (Spraybild S2 from 13 ) only with partially opened injector, so that fuel only via the first injection hole arrangement 101 is injected.

The 14 and 15 show a further embodiment of the invention, wherein the HCCI combustion process with only Compression stroke injection is performed. 14 shows here the part-load operation, with a pilot injection (Spraybild S1 ) with a fuel amount M1 and a main injection (spray picture S2 ) with a fuel amount M2 is made shortly before the ZOT. At full load operation ( 15 ), the pre-injection takes place (Spraybild S1 ) only via the first spray hole arrangement 101 and the main injection (spray picture S2 ) takes place when the injector is fully open. This results in the fuel quantities shown M1 and M2 , In both combustion of 14 and 15 there is a self-ignition.

To the 8th to 15 It should be noted that in this case also multiple injections are possible. These are exemplified in the figures by the reference numerals M1 ' such as M2 ' indicated. For example, in the in the 8th and 9 shown embodiment after the first intake stroke injection still a second suction stroke injection M1 ' be executed. Furthermore, as in the embodiment in the 12 and 13 also shown a double compression stroke injection M2 ' respectively.

Furthermore, it should be noted in all the described exemplary embodiments that the combustion method is used in conjunction with the injector according to the invention 1 can be significantly improved. In particular, in an Otto internal combustion engine, an injection pressure up to 2000 × 10 ⁵ Pa can be used.

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

• WO 2006/040283 A1 [0002]
• DE 102015223437 [0002]
• DE 102010063355 A1 [0002]

Claims (14)

Injector for injecting fuel, in particular directly into a combustion chamber of an internal combustion engine, comprising: a one-piece closure element (2), a valve body (3), a first injection-orifice arrangement (101) in the valve body (3) having a plurality of first injection holes (31), a second injection-orifice arrangement (102) in the valve body (3) with at least one second injection hole (32), wherein the first spray-hole arrangement (101) is offset from the second spray-hole arrangement (102) in the axial direction of the injector by a predetermined distance (A), - A first sealing seat (4) between the closing element (2) and the valve body (3), and a second sealing seat (5) between the closing element (2) and the valve body (3), which is arranged in the axial direction of the injector between the first and second injection-orifice arrangement (101, 102), - wherein the second sealing seat (5) in the axial direction has a cylindrical sealing surface with a predetermined length (L) in order to achieve a stepped injection of the fuel in the opening case of the injector, and - Wherein the first spray hole arrangement (101) has the same number of or more spray holes than the second spray hole arrangement (102). Injector after Claim 1 wherein a maximum flow rate through the first spray holes (31) of the first spray hole assembly (101) is in a range of 30% to 40% of a total flow through all the spray holes of the first and second spray hole assemblies (101, 102). Injector according to one of the preceding claims, wherein all spray cones (11, 12, 13, 14, 15), which are generated by the first injection nozzle arrangement (101), from a central axis (XX) of the injector, in particular up to a distance of at least 30th mm from an injector tip, farther away than the spray cones (21, 22, 23, 24, 25) produced by the second spray-hole arrangement (102). Injector according to one of the preceding claims, wherein at least one spray hole (31) of the first spray hole arrangement (101) are arranged such that a spray lobe (11, 12) generated by the spray hole is directed towards an ignition device and / or adjacent to the ignition device , Injector according to one of the preceding claims, wherein an injection direction through the injection holes of the first and second spray nozzle assemblies (101, 102) is such that the injection direction of all injection holes is different. Injector according to one of the preceding claims, wherein injection holes of the first injection-molding arrangement (101) lie in a first plane (E1) and injection holes (32) of the second injection-molding arrangement (102) lie in a second plane (E2), the planes (E1, E2 ) are spaced from each other in the axial direction (XX) a distance (A). Injector according to one of the preceding claims, wherein the first sealing seat (4) is a tapered sealing seat, in particular a conical sealing seat. Internal combustion engine (100) comprising an injector (1) according to one of the preceding claims. Internal combustion engine after Claim 8 , further comprising a control unit, which is configured to open only the first injection nozzle arrangement (101) during a partial load request of the internal combustion engine and to open the first and second injection nozzle arrangements (101, 102) when the load demand is greater than the partial load requirement, in particular a full load requirement. Internal combustion engine after Claim 8 further comprising a control unit configured to selectively open only one or both of the spray-hole assemblies during the suction stroke or compression stroke, optionally at partial load request or full-load request. Internal combustion engine after Claim 8 or 9 or 10 comprising an ignition device (6), wherein the injector is arranged such that at least one spray lobe (11) of a spray hole (31) of the first spray hole arrangement (101) is directed towards the ignition device or immediately adjacent to the ignition device. Internal combustion engine according to one of Claims 8 to 11 , characterized by a homogeneous combustion method with an air ratio of λ ≥ 1, in particular λ ≥ 2. Internal combustion engine after Claim 12 characterized by a HCCI combustion method with auto-ignition or with ignition assistance. Use of an injector (1) according to one of Claims 1 to 7 in an Otto internal combustion engine (100).

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