EP1485609A1

EP1485609A1 - Device for injecting fuel to stationary internal combustion engines

Info

Publication number: EP1485609A1
Application number: EP03704234A
Authority: EP
Inventors: Jaroslaw Hlousek
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2002-03-08
Filing date: 2003-01-20
Publication date: 2004-12-15
Anticipated expiration: 2023-01-20
Also published as: ATE308677T1; EP1485609B1; DE10210282A1; JP4404640B2; WO2003076794A1; US7025045B2; CN1507538A; JP2005519233A; DE50301551D1; US20040187848A1; CN100365269C

Abstract

The invention relates to a fuel injection system for use in internal combustion engines having delivery units for delivering fuel from a fuel reservoir in order to supply at least one high-pressure line to the cylinders of the engine. The at least one high-pressure line supplies a number of fuel injectors, which each include an injector nozzle that supplies fuel to a combustion chamber of the engine and includes line segments that connect the individual fuel injectors to one another. The injector bodies of the fuel injectors each have an accumulator chamber integrated into them.

Description

Device for injecting fuel into stationary internal combustion engines

Technical field

Nerbrennerlαaftmaschinen, which are used as vehicle engines, stationary engines (generator engines) or for driving ships, usually have between 2 and 20 cylinders. In the case of these internal combustion engines, the bore diameter of the respective cylinders is within a broad spectrum, in some cases up to 500 mm in the case of large diesel engines. Depending on the number of cylinders, individually tailored fuel injection systems are used, which must be individually matched to the number of cylinders.

State of the art

DE 198 37 332 AI relates to a control unit for controlling the pressure build-up in a pump unit. The control unit has a control valve and a valve actuation unit connected to it. The control valve is designed as an I-valve opening inwards in the direction of flow, which has a valve body which is axially displaceably mounted in a housing of the control unit and which, when the control valve is closed, is seated on the inside of a valve seat of the control valve. A throttle arrangement is provided, by means of which the flow through the control valve is throttled when the control valve is opened by one stroke h. When the control valve is opened by this stroke, the valve seat is still open, but a further valve seat formed on the control valve is closed, so that the pumped medium flows through the control valve via the throttle bores. Due to such a throttled flow through the control valve, a lower pressure is initially built up in a high-pressure area of the system. When the control valve is completely closed, however, both the first valve seat and the further valve seat are closed, as a result of which the bypass connection is interrupted becomes. This leads to build up a high pressure between the pump unit and the low pressure area of system compared to the ^{'high-pressure} region.

DE 42 38 727 AI relates to a solenoid valve. The solenoid valve serves to control the passage of a connection between a high-pressure chamber, at least temporarily brought to high fluid pressure, in particular a pump work chamber of a fuel injection pump and a low-pressure chamber. A valve body inserted into a valve housing and a bore arranged therein are provided, in which a valve closing member in the form of a piston can be displaced by an electromagnet against the force of a return spring. The piston tapers, starting from a circular cylindrical outer surface via a conical surface to a reduced diameter, the conical surface interacting with a conical high pressure space surrounding the circular cylindrical outer surface of the piston with a connecting valve seat surrounding the reduced diameter of the piston on the valve body. Whose cone angle is formed smaller than the cone angle of the conical surface of the piston, so that the piston cooperates with the associated valve seat via a sealing edge formed at the transition between its cylindrical outer surface and the conical surface. In the overflow direction from the high-pressure chamber to the low-pressure chamber, the sealing edge is followed by a throttle point which becomes effective at the start of the opening stroke. This throttle point is formed by a throttle section in the overlap area between the angular surface of the piston and a valve seat surface, the angle of the conical surface of the piston being slightly, preferably 0.5 ° to 1 °, larger than the angle of the valve seat surface, so that the passage cross section between the conical surface of the piston and the valve seat surface over the entire circumference in the overflow direction to the low-pressure chamber at the beginning of the opening stroke steadily decreases. Due to the high flow velocities of the fuel between the injection phases - be it pre-, main or post-injection phases - cavitation damage cannot be completely ruled out with this solution.

Presentation of the invention

The advantages of the solution according to the invention are present. All this in that an injector construction principle can be used regardless of the number of cylinders in the crimping juice machine, the engine configuration (V-arrangement, W-arrangement, row arrangement) by using the high-pressure supply line sections instead of a rail component to connect decentrally arranged accumulators. The Hochdruclczuleitungsab- ^'sections in turn connect the individual injectors to each other; they are interchangeable and can be adapted to different cylinder distances between the cylinders on the individual cylinder banks of the internal combustion engine. The proposed solution offers increased flexibility in the construction of an injection system and its simple adaptability to different engine configurations, be it cylinder arrangements in V, W or in series construction.

The modularity principle is equally implemented in the construction of the fuel injector used. Injection nozzles, intermediate plates with the inlet and outlet throttle designed in them, valve units and injector bodies are used on the respective injectors. By changing the intermediate plate, for example, the pressure relief or pressurization of the control chamber of the injector can be influenced by the dimensioning of the throttle cross-sections and can be adapted to the most varied application conditions of the injector. The injector body used on the modular injector can be designed in different lengths and can thus be optimally adapted to the available space. The injector body comprises a storage space, the storage volume of which is approximately less than 80 times the maximum amount of fuel injected. This reservoir is acted upon by a supply throttle formed in the head region of the fuel injector with fuel under high pressure. The memory integrated in the injector body is followed by a flow limiter which limits the flow rate of the fuel to the nozzle chamber. The inlet throttle to the accumulator in the head region of the injector is preferably designed such that multiple injection is possible without pressure pulsations occurring in the high-pressure line sections which are connected to the head region of the fuel injector. This also does not disturb the stable pressure level in the stores of the other injectors for injecting fuel. Advantageously, the pressure level in the storage space integrated in the injector body can be kept at a pressure level by its inlet throttle which corresponds to the pressure level prevailing in a pressure accumulator integrated in one of the delivery units.

The pressure pulsations in this accumulator and between the accumulator and the nozzle are significantly smaller compared to conventional injection systems thanks to the small distance between the accumulator and the nozzle.

The respective injection processes become independent of the engine configuration of the internal combustion engine, the length of the high-pressure line sections and the number of cylinders of the internal combustion engine via the storage spaces integrated in the injector body, their inlet throttle and on a storage space integrated or accommodated in the vicinity of the delivery units. The injection system can be based on the central storage arrangement for damping the pump pulsation on a large number of differently configured internal combustion engines and thus considerably reduces the number of variants with regard to the required structural components. The storage space assigned to the delivery units and the injector-side pressure accumulator are connected to one another by simple, modularly constructed and therefore easily interchangeable high-pressure expansion sections, which significantly simplifies the adaptability of the injection system to a wide variety of combustion-power-crime-gas configurations and the quality of the injection processes, regardless of the length of the line connecting the storage spaces Line sections will.

drawing

The invention is described in more detail below with the aid of the drawing.

It shows:

1 shows the components of an injection system,

FIG. 2 shows the construction principle of a fuel injector of the injection system according to FIG. 1,

Figure 2a shows the enlarged view of the throttle geometry of the inlet throttle to the storage space

3 shows the longitudinal section through an embodiment of an injector according to Figure 2 and

FIG. 4 shows the top view of the embodiment variant of the injector according to FIG. 3.

FIG. 5 shows a top view of an embodiment variant of the fuel injector with transverse storage space,

FIG. 6 shows the embodiment variant according to FIG. 5 in section,

FIG. 7 shows the schematic representation of a further embodiment variant with a high-pressure connection piece as part of the injector,

Figure 8 is a schematic diagram of the high pressure connector and FIG. 9 shows the representation of further installation components in a fuel injector below the storage space 36 integrated therein

design variants

FIG. 1 shows the components of an injection system.

The injection system shown in FIG. 1 for supplying an internal combustion engine with fuel comprises a fuel reservoir 1. A feed pump 2 delivers fuel from the fuel reservoir 1. On the pressure side, the pump umpe 2 is followed by a high-pressure pump unit 3, which is preceded by a throttle point 4. The throttle point 4 is a variable throttle point that can be controlled via a control unit 12. The Fördeφumpe 2 is a pressure control valve 8 downstream, which controls the inlet pressure to the high pressure pump unit 3 and is in communication with the fuel reservoir 1.

The high-pressure pump unit 3 comprises an integrated pressure accumulator 5. The pressure accumulator 5 is secured by a pressure relief valve 7, the outlet of which opens into the fuel reservoir 1. Furthermore, the integrated pressure accumulator 5 comprises a pressure sensor 6, which is connected to the control unit 12 and via which the pressure prevailing in the integrated pressure accumulator 5 is reported back to the control unit 12. A first high-pressure line 9 branches off from the integrated pressure accumulator 5 High-pressure line 9 can be used, for example, to supply the injectors 11 of the cylinders of a first cylinder bank of an internal combustion engine with fuel under high pressure. This configuration of an injection system is selected, for example, when supplying cylinders to an internal combustion engine designed in series. In addition, other high-pressure supply lines can also be provided by the integrated pressure accumulator 5 1, a further high-pressure line 10 for supplying the injectors 11 of cylinders of a further engine bank of an internal combustion machine is indicated schematically, with di e cylinders of such a combustion lcraft machine can be arranged in a V design. In addition, a third high-pressure feed line, not shown in FIG. 1, can branch off to a third cylinder bank, for example in the case of internal combustion engines, the cylinders of which are arranged in a W design and consequently three or more cylinder banks are formed. The first high-pressure feed line 9 leading away from the integrated pressure accumulator 5 merges into a first line section 17. The line section 17 is connected in the head region 15 of the injector 11. A first line section 17.1 branches off from the head region 15 of the injector 11, at the end of which an injector nozzle 16 is arranged on the combustion chamber side, and is connected to the head region 15 of a further injector 11. A further line section 17.2 branches off from its head region 15 to the head region 15 of the next injector 11. Depending on the number of cylinders on a cylinder bank of an internal combustion engine, the sequence of line sections 17, 17.1, 17.2 can be continued to further injectors 11, not shown here, for injecting fuel into the cylinders of the internal combustion engine. The individual injectors 11 for supplying the combustion chambers of an internal combustion engine with fuel are each electronically controlled via the control unit 12 via controls 14. The individual injectors 11 are connected via low-pressure line sections 13 to a collecting line via which the leakage quantity or control quantities of the injectors are fed to the fuel reservoir 1 on the low-pressure side. The injectors 11 of a second and a third cylinder bank - which are not shown in FIG. 1 - are connected on the low pressure side via low pressure ducts 13 to the fuel reservoir 1, into which the leakage or discharge quantities of the injectors 11 are reclaimed.

FIG. 2 shows the construction principle of an injector which is used on injection systems as shown in FIG. 1.

The illustration according to FIG. 2 shows that the injector 11 shown there comprises an injector body 20, a control part 21, an intermediate plate 22 and an injector nozzle 16 at the end on the combustion chamber side.

The injector nozzle 16 comprises a nozzle needle 23 which is arranged to be movable in the vertical direction. The nozzle needle 23 comprises a needle guide 24, on which individual flow free areas are arranged, offset in the circumferential direction with respect to the nozzle needle 23, via which fuel flows from a nozzle needle space 40 to the nozzle needle tip, is present there and when the nozzle needle 23 moves vertically upward is injected into the combustion chamber of the internal combustion engine via one or more injection openings 38.

The nozzle needle 23 comprises a collar on which a spring 26 is supported. The spring 26 acts on an upper collar of a sleeve-shaped component 25, which is pressed against the underside of the intermediate plate 22 by the spring 26 supported on the collar of the nozzle needle 23. The sleeve-shaped component 25 and the upper end face the nozzle needle .23 delimit a control chamber 27, the pressurization or pressure relief of which causes the vertical movement of the nozzle needle 23 within the nozzle body. The nozzle chamber 27 is acted upon on the one hand by an inlet throttle 28 implemented in the intermediate plate via a fuel high pressure line 29 with fuel under high pressure. On the other hand, the control chamber 27 is relieved of pressure via an outlet throttle element 30 likewise formed in the intermediate plate 22. To relieve pressure in the control chamber 27, a valve 31 is provided in the control part 21, which valve is actuated via an actuator 34 formed in the injector body 20. The actuator 34 is formed in the schematic diagram as shown in Figure 2 as a ring magnet and is controlled by the control unit 14 by means of the control unit 12. The valve 31 is provided with an anchor-type valve plate 32, which is pressed into its seat 42 formed in the control part 21 via a spring element 33 enclosed by the electromagnet 34. When the seat 42 is closed, ie the actuator 34 is not activated, an outlet channel 41, which is connected downstream of the outlet throttle 30 of the control chamber 27, is closed. Below the valve seat 42 of the valve 31 in the control part 21 there extends a drain channel configured in a meandering manner, which is connected to a drain channel 43 which is formed in the injector body 20. Controlled fuel volume flows via the outlet channel 43 into the lines 13 provided on the low pressure side (cf. illustration according to FIG. 1).

The injector body 20 of the fuel injector 11 comprises a storage space 36. The storage volume in the storage space 36 is less than 80 times the maximum injection quantity, which is injected via the injection openings 38 on the injector nozzle 16 into a combustion chamber of a combustion air machine, not shown in FIG. The storage volume of the storage space 36 is preferably 60 to 80 times the injection quantity. The storage space 36 in the head region 15 of the injector body 20 is acted upon by fuel under high pressure via an inlet throttle 37. The inlet throttle 37 in turn branches off from a channel 44 also formed in the head region of the injector body 20. The channel 44 is acted on the one hand via the line section 17 of the high-pressure feed line 9 with fuel under high pressure; on the other hand, the channel 44 in the head region 15 of the injector body 20 is connected to a further head region 15, not shown here, of a further fuel injector 11 via the first leverage section 17.1. The channel cross section of the channel 44 in the head region 15 of the injector 20 is identified by reference numeral 45. Accordingly, via the line section 17 of the high-pressure line 9, the pressure accumulator 5 integrated in the high-pressure pump unit 3 and — with the interposition of the inlet throttle 37 — the pressure accumulator 36 within the injector body 20 are connected. The dimensioning of the inlet throttle 37 between the channel 44 in the head region 15 of the injector body 20 and the soapy storage space 36 ensures the independence of the individual Injection events independent of the number of cylinders of Verbrennungskra: ftrnaschi- ne, regardless of the engine configuration, be it in ^'series construction, in V-arrangement or in the arrangement and W independent of the length of the individual connecting lines with each other. Furthermore, a suitable design of the inlet throttle 37 to the storage space 36 in the injector body 20 ensures that injection processes which are connected several times in succession are possible without pressure pulsations building up in the storage space 36 and in the line sections 17 and 17.1 and thereby also influencing other fuel injection injectors 11. This enables pre-injection, main injection and post-injection phases to be carried out without pressure pulsation. The inlet throttle 37 to the storage space 36 allows almost identical pressure levels to be maintained in the storage space 36 before the injection process and in the integrated pressure reservoir 5 of the high-pressure pump unit 3. The throttle geometry of the inlet throttle 37 to the storage space is advantageously carried out with different flow coefficients, as shown in FIG. 2a. see. Reference number 37.1 can be removed. ,

A flow limiter 35 is connected downstream of the storage space 36 in the injector body 20 of the fuel injector 11. The body of the flow restrictor 35 contains a transverse bore with throttling action 54 and is prestressed by a spring element 46. The flow limiter 35 is downstream of the storage space 36 and upstream of the high-pressure fuel line 29 of the injector body 20. An undesired excess in the event of a malfunction, which, for example in the case of a leaky nozzle, prevents or is restricted in such a way that the occurrence of an undesirable excess is only possible during an injection process, via the flow limiter 35. At the body of the flow restrictor, the transverse bore 54 is formed such that it extends perpendicular to the axis of symmetry of the body of the flow restrictor 35, the bottom region of the body of the flow restrictor being closed, so that fuel flows away only through the openings of the cross bore 54 in the Wall of the body of the flow restrictor 35 adjusts. The high-pressure fuel line 29 adjoining the flow limiter 35 in the injector body 20 extends through the control part 21 before the high-pressure fuel line 29 opens into a two-armed channel in the intermediate plate 22. One arm of the channel in the intermediate plate 22 runs out in the inlet throttle 28 for pressurizing the control chamber 27, while the further arm of the channel opens into a nozzle needle chamber 40. Fuel enters the annular space surrounding the nozzle needle 23 below the needle guide 24 via the nozzle needle chamber 40 and the flow-free areas formed on the needle filling 24 and - assuming a corresponding vertical stroke movement of the nozzle needle 23 - is injected into the combustion chamber (not shown here) via the injection openings 38 an internal combustion engine injected. The modular fuel injector 11, comprising an injector body 20, a control part 21, the intermediate plate 22 and an injector nozzle 16, is mounted with the aid of a nozzle lock nut 39 designed as a union nut. The modular design advantageously favors the replacement of the intermediate plate 22, in which the inlet throttle 28 and the outlet throttle 30 are formed, with another intermediate plate 22 of the same height, in which the inlet throttle 28 or the outlet throttle 30, which relieves the control chamber 27, in larger sizes or smaller diameter geometries are designed to be exchanged. Thus, by simply replacing the modular intermediate plate 22, a different pressure build-up or pressure relief behavior in the control chamber 27 and a different stroke characteristic of the nozzle needle 23 resulting therefrom can be set. The modular structure of the fuel injector 11 in accordance with the basic illustration in FIG. 2 also offers the advantage that the space available in the cylinder head area of an internal combustion engine can be advantageously used by different designs of the injector body 20 in different heights.

Figure 2a shows an enlarged view of the throttle geometry of an inlet throttle point to the storage space.

The inlet throttle 37 advantageously has a rounded inlet on the side facing the line sections 17, 17.1, which promotes an inflow of fuel into the storage space 36. The throttle bore of the inlet throttle 37 narrows continuously towards its mouth in the storage space 36. The angle at which the cross-sectional narrowing in the direction towards the storage space 36 zulau- conically formed fend, is preferably ^'in the range between 10 ° and 20 ° with respect to the axis of symmetry of the throttle bore of the inlet throttle 37. At the mouth of the inlet throttle 37 in the Storage space 36, the throttle bore is formed with sharp edges, which counteracts a backflow of fuel via the inlet throttle 37 into the channel 44 between the line sections 17, 17.1.

FIG. 3 shows the longitudinal section through an embodiment variant of the fuel injector according to FIG. 2.

In the embodiment variant of the fuel injector according to FIG. 3, an insert 51 is screwed to the injector body 20 in the head region 15 of the injector by means of a clamping nut. The channel 44, which is connected to the storage space 36 via an inlet bore throttle 37, runs perpendicular to the plane of the drawing. The operational 03 00139

-10- piece 51 protrudes with its lower region into a cavity 52 formed in the injector body 20 and acts on it via two openings formed in the wall of the insert 51. The flow limiter 35 (see the basic illustration according to FIG. 2) adjoins the insert piece 51, which is connected downstream of the storage space 36 and upstream of the high-pressure fuel line 29. The screw connection between the clamping nut 50 and the stop of the injector body 20 is identified by reference number 53. The high-pressure fuel line 29 extends slightly inclined through the injector body 20 and merges into a corresponding bore section on the control part 21, passes through the intermediate plate 22 before the high-pressure fuel line 29 opens at the nozzle needle chamber 40 of the injector nozzle 16. In the injector nozzle 16, the nozzle needle 23 is mounted in a needle guide 24 so as to be movable in the vertical direction. The nozzle needle 23 is pressurized via a spring element 26. The valve 31 is accommodated in the control part 21 of the injector configuration according to FIG. 3, the valve disc 32 of which can be moved in the vertical direction via an actuator 34 designed as a ring magnet. The ring magnet 34 encloses the valve 31 in its closing position closing spring 33; the electromagnet 34 of the actuator 31 actuating the actuator is controlled via connecting lines 14 which extend substantially in the vertical direction through the injector body 20, the corresponding connection 55 is formed on the side of the injector body 20 and is designed as a plug contact. The nozzle clamping nut 39 enclosing the injector nozzle 16 also receives the intermediate plate 22 and the control part 21 which receives the actuatable valve 31. The nozzle clamping nut 39 and the lower end of the injector body 20 are screwed together. In the embodiment variant of the fuel injector 11 according to FIG. 3, both the inlet throttle 28 which pressurizes a control chamber 27 and the outlet throttle 30 which relieves pressure from the control chamber 27 are formed in the intermediate plate 22, but are not shown in the representation according to FIG. 3, cf. basic illustration according to FIG. 2.

FIG. 4 shows the top view of the variant of the injector according to FIG. 3.

In the head region 15 of the fuel injector 11 as shown in FIG. 4, the insert 51 is shown partly in section. The line sections 17 and 17.1 of the first high-pressure line 9 shown in FIGS. 1 and 2 are connected to the chamfering of the channel 44 which ends at an angle. The inlet throttle 37 branches off from the channel 44 in the insert 51 and is used to apply fuel under high pressure to the storage space 36 formed in the insert 51. The insert 51 and the injector body 20 of the fuel injector 11 are screwed together via a clamping nut 50. In the representation of the top view according to FIG. 4, the plug connections 55 can be seen, with which one is configured, for example, as an electromagnet Actuator, which can be accommodated within the injector body 20, is controlled. Reference numeral designates the nozzle clamping nut 39, in which both the injector nozzle 16 and the intermediate plate 22 lying above it and the control part 21 are received, and with the internal thread formed at the upper region these structural components are mounted with the end of the injector body 20 on the combustion chamber side. From the injection openings designated by reference numeral 38, the fuel is injected into the combustion chambers of the internal combustion engine, whether their cylinders are arranged in a row, in a V arrangement or in a W arrangement.

Figure 5 shows a variant of the fuel injector with transverse storage space in plan view.

The channel 44, which is formed in the channel cross section 45, extends through the housing of the storage space 36 between the line section 17 and the first line section 17.1. The channels separated from each other by a cavity in the housing of the storage space 36 open into the latter, in which an inlet throttle body 37 is embedded. The body of the inlet throttle 37 has a flow-optimized throttle geometry 37.1 at the end opposite the cavity mentioned and can be rounded at the entry point. According to the throttle geometry shown in FIG. 2a in an enlarged cross-section, the throttle channel can have a cross-section that continuously narrows to its point of discharge into the storage space 36, the wall of the throttle bore within the throttle body 37 at an angle between 10 ° and 20 ° with respect to the center line the throttle bore runs obliquely. The storage space taken up in the transverse orientation 48 in the head region 15 of the fuel injector 11 in the embodiment variant according to FIG. 5 is closed in a pressure-tight manner by a closure 47, which can be designed, for example, as a screw-in element. The flow limiter 35, indicated here in dashed lines, is connected to the interior of the storage space 36 in the transverse direction 48 via a channel 49. Fuel flows through the channel 49 from the interior of the storage space 36 to the flow limiter, which regulates the flow of fuel in the direction through the high-pressure fuel line 29 to the injection nozzle of the fuel injector 11.

FIG. 6 shows the embodiment of the fuel injector according to FIG. 5 with the storage space installed in the transverse direction on average.

6 shows that, for reasons of strength, the channel 49, which connects the storage space 36 to the flow limiter 35, branches off tangentially from the circumference of the storage space 36, in order to avoid material-draining stresses on the material. rials of the injector body 20. Above the flow limiter 35, the injector body 20 is closed in a pressure-tight manner by a screw-in closure 47. The screw-in closure 47 favors the simple assembly of the spring 46 acting on the flow limiter 35, which is let into the interior of the injector body 20 above the high-pressure fuel line 29. Analogously to the representation of the flow limiter in FIG. 2, the flow limiter 35 shown in FIG. 6 likewise comprises a transverse bore 54 and is preloaded analogously to the representation of the flow limiter 35 in the embodiment variant of the solution proposed according to the invention by a spring element 46 designed as a spiral spring.

Figure 7 shows the schematic representation of an embodiment with a high pressure connector as part of an injector body.

In contrast to the embodiment variant of the injection system for larger self-igniting internal combustion engines shown in FIG. 1, the fuel injectors 11 according to the diagram shown in FIG. 7 are not directly through the inlet throttle through the channels 44 between the line sections 17, 17.1 and 1.2 in the head region 15 of the injector 37 acted upon. A high-pressure line connecting piece 100 extends between the inlet throttles 37, which are preferably designed in a geometry according to the geometry shown on an enlarged scale in FIG. 2a. This high-pressure line connecting piece 100, essentially designed as a tubular body with a thickened wall, acts on the fuel injector 11 with under high pressure fuel.

The throttle point 4, the high-pressure pump unit 3, the pressure sensor 6, the pressure relief valve 7 and the high-pressure line 9 or 10 to the cylinder banks of the internal combustion engine essentially correspond to the components of the injection system already shown in FIG.

Figure 8 shows a schematic diagram of the high-pressure connector, which extends between the channel 44 and the injector body 20 of the fuel injector 11.

From the illustration according to FIG. 8 it can be seen that, analogously to the illustration of the embodiment variants according to FIGS. 2, 3, 4 and 5, the inlet throttle 37 is acted upon by a channel 44 which is formed in a channel cross section 45. The high-pressure line sections 17.2 and 17.1 - here indicated by dashed arrows - are fastened to this via the connection points shown in FIG. Via the inlet throttle 37, which preferably has a throttle geometry 37.1 shown in FIG. is formed, the high-pressure connector 100 is acted upon, which comprises a further storage space 36.1, which is essentially symmetrical to the axis 103 of the high-pressure connector 100. The high-pressure connector 100 extends in a length 101 between the head region 15 and the injector body 20 of the fuel injector 11. Via the inlet throttle 37, fuel enters from the channel 44 into the further storage space 36.1 within the high-pressure connector 100, flows through an L- shaped line connection 104 into the interior of the storage space 36 in the upper region of the injector body 20 of the fuel injector 11. The fuel injector 11 comprises a union nut 39, shown schematically here, via which the injection nozzle part 16 is connected to the injector body 20 by a screw connection. The high-pressure connection piece 100, comprising a further storage space 36.1, which is essentially tubular, is connected to the injector body 20 of the fuel injector 11 at a connection point 102 designed as a sealing.

The embodiment shown in FIG. 8 can on the one hand improve the flexibility when installing the fuel injectors 11 and with regard to the line connection between the line sections 17.1, 17.2 and the injector body 20. On the other hand, the volume of the storage space 36 can be increased by integrating the additional storage space 36.1 into the interior of the high-pressure line connection 100.

FIG. 9 shows the representation of further installation components in a fuel injector below the storage space integrated in the injector body.

The further storage space 36.1, which is pressurized with fuel under high pressure via the inlet throttle 37 (not shown in FIG. 9) and which is formed in the high-pressure line connection 100, extends essentially coaxially with the axis of symmetry 103 of the high-pressure line connection piece. This is preferably screwed laterally into the injector body 20 of the fuel injector 11 by means of a screw thread 102. In the area of a transition bore 106, the fuel volume overflows from the further storage space 36.1 into the storage space 36 inside the injector body 20 of the fuel injector 11. The storage space 36 within the injector body 20 is closed in a pressure-tight manner via a screw-in closure 47 on the upper side of the fuel injector 11. Below the storage space 36 in the injector body 20 is the flow limiter 35, which is biased via a spring element 46 analogously to the flow restrictors 35 shown in FIGS. 5 and 2. The high-pressure line 29 extends below the flow limiter 35, which - cf. Representation according to FIG. 2 - by means of a control part 21, an intermediate plate 22, a nozzle needle space 40 within the fuel injector 11, are subjected to fuel under high pressure. With reference numeral 33 is one Denoted closing spring, which acts on an electromagnet 34 (not shown in Figure 9). The control part 21 is connected via the nozzle clamping nut 39 on a screw connection 105 to the lower region of the injector body 20 of the fuel injector 11 in a pressure-tight and centered manner. The leakage oil channel is designated by reference numeral 43, while the actuation of the electromagnetic valve 34, not shown in FIG. 9, of which the closing spring 33 is only shown schematically, is designated by reference numeral 14. Due to the way in which the storage space 36 is acted on indirectly via a further storage space 36.1, which is integrated into the interior of a high-pressure line connection 100, the height of the injector, which is generally in the cylinder head area, can be compared to the embodiment variant according to FIG must be accommodated by auto-ignition internal combustion engines, which improves its installation options in the cylinder head area. The embodiment of the storage arrangement in the transverse direction 48 shown in FIGS. 5 and 6 can also significantly improve the installation height on a fuel injector, so that a more flexible construction of injectors is possible, in particular an integration of the storage space 36 or another proposed according to the invention Storage space 36.1 in a high-pressure connector 100 having fuel injectors 11 in the cylinder head area can be significantly improved.

LIST OF REFERENCE NUMBERS

1 fuel reservoir

2 Fördeφumpe 3 high pressure pump unit

4 throttling point

5 integrated pressure accumulators

6 pressure sensor

7 Pressure relief valve 8 Pressure control valve

9 High pressure line, first cylinder bank

10 high pressure line additional engine bank

11 fuel injector

12 control unit 13 low pressure line

14 control

15 injector head area

16 injector nozzle

17 line section 17.1 first line section

17.2 further line section

20 injector bodies

21 control unit 22 intermediate plate

23 nozzle needle

24 needle guide

25 sleeve

26 spring element 27 control room

28 Inlet throttle control room

29 High pressure fuel line

30 flow restrictor

31 valve 32 valve plate (armature)

33 closing spring

34 electromagnet

35 flow limiter 36 storage space

36.1 additional storage space

37 Inlet throttle, storage space 37.1 Throttle geometry 38 Injection openings

39 Nozzle clamping nut

40 nozzle needle chamber

41 drain channel

42 Valve seat 43 Leakage oil duct

44 channel

45 channel cross-section

46 spring element

47 lock 48 transverse orientation storage space 36

49 channel

50 clamping nut

51 Injector head insert

52 cavity 53 threaded connection

54 cross hole

55 electrical connection

100 high pressure fitting 101 length from high pressure fitting

102 attachment

103 axis of symmetry

104 channel connection

105 threaded connection 106 transition hole

Claims

claims

Injection system for fuel for use on internal combustion engines, with delivery units (2, 3) for delivering fuel from a fuel reservoir (1) to supply at least one high-pressure line (9, 10) to the cylinders of the internal combustion engine, the at least one high-pressure line ( 9, 10) a number of fuel injectors (11) are supplied which contain an injector nozzle (16) which supplies a combustion chamber of the internal combustion engine with fuel, characterized in that the at least one high-pressure line (9, 10) line sections (17, 17.1, 17.2) with which the individual fuel injectors (11) are connected to one another, each of which contains a storage space (36, 36.1) integrated in an injector housing (20).

Injection system according to claim 1, characterized in that the storage space (36) is arranged in the head region (15) of the injector body (20).

Injection system according to claim 1, characterized in that the storage space (36) in the injector body (20) is arranged in the longitudinal direction.

Injection system according to claim 2, characterized in that the storage space (36) in the injector body (20) is accommodated in the transverse direction.

Injection system according to Claim 1, characterized in that the storage space (36) in the injector body (20) is connected to the line separations (17, 17.1, 17.2) via a high-pressure connector (100) containing a further storage space (36.1).

Injection system according to claim 1, characterized in that in the head region (15) of the fuel injector (11) there is a channel (44) which is subjected to high pressure via line sections (17, 17.1) of the high pressure line (9, 10) and in the head region (15 ) of the fuel injector (11) branches off an inlet throttle (37) to the storage space (36). ^•

Injection system according to claim 6, characterized in that the head region (15) of the fuel injector (11) is designed as an insert (51) which is connected to the

Injector body (20) is sealingly connected.

8. Injection system according to claim 1, characterized in that the storage space (36) in the injector body (20) is followed by a spring-loaded flow limiter (35) and a fuel high pressure line (29) to the nozzle needle space (40) is connected upstream.

9. Injection system according to claim 1, characterized in that the injector (11) is modular, comprising an injector body (20), a control part (21), an intermediate plate (22) and an injector nozzle (16).

10. Injection system according to claim 9, characterized in that in the intermediate plate (22) a control chamber (27) pressure-relieving or pressurizing throttle elements (28, 30) are formed.

11. Injection system according to claim 6, characterized in that the control chamber (27) is delimited by a sleeve (25), a nozzle needle (23) which can be moved relative to the latter and the intermediate plate (22).

12. Injection system according to claim 1, characterized in that the volume of the storage space (36) corresponds to 50 times to 80 times the maximum injection quantity.

13. Injection system according to claim 1, characterized in that the supply space (36) assigned to the inlet throttle (37) is designed such that the pressure level in the storage space (36) of the fuel injector (11) is integrated into one of the delivery units (2, 3) Pressure accumulator (5) corresponds to the prevailing pressure level.