DE102012012420A1 - Injector and fuel injection device with such - Google Patents

Abstract

Injector (1) for a fuel injection device, the injector (1) having a control chamber (7) via which the stroke position of a nozzle needle (3) of a nozzle valve (4) of the injector (1) can be controlled, the injector (1) being a first 2/2-way valve (12), in particular a pilot valve, by means of which a first flow branch (8) in communication with the control chamber (7) can be optionally interrupted and a second 2/2-way valve (15), in particular a pilot valve, by means of which a second flow branch (9) can optionally be interrupted in the process. A fuel injection device with such an injector is also proposed.

Description

The present invention relates to an injector according to the preamble of claim 1 and a fuel injector with such according to the preamble of claim 7.

In generic injectors for fuel injectors, which are designed with a pilot valve, the slope of the flow rate characteristic is set (especially in the non-linear region). It can only be influenced by changing the system pressure. This applies equally to systems with a 2/2-way valve as well as with a 3/2-way valve. However, a provided independently of the system pressure characteristic variability is desirable in order to extend the operating range of internal combustion engines, which are operated by a generic injector in the middle and lower engine load and further stable small amounts (flat curve) represent and the ballistic region of the nozzle needle for a higher beam pulse in the exhaust gas-relevant partial load range z. B. to shorten vehicles (steep curve).

From the publication DE 197 34 354 A1 For the modulation of the injection curve, an injector with a modulation device is known, which forms a continuously increasing injection rate profile after the start of injection. The disadvantage here is that the characteristic of the modulation valve can not be influenced. From the same document, such. B. also from the document DE 196 09 799 C2 Furthermore injectors with two solenoid valves are known, ie of the type "Ganser", wherein a valve is actively controlled and the other pressure-dependent or pressure-controlled switched, so that high speeds for opening and closing of the nozzle valve can be achieved. However, here too no characteristic variability over the valves system pressure independent adjustable.

The publication DE 10 2007 010 498 A1 further shows an injector with a 3/2-way valve, but again no characteristic variability. The publication DE 101 32 248 A1 also discloses a fuel injector with 2-way valve control, the valves are switchable via a common actuator, with a fixed game in the switching path determines the dead time and thus the stroke characteristics. Due to the non-variable game, however, this system is also insufficiently flexible.

The publication DE 197 42 320 A1 also discloses a fuel injector having a control valve and a safety valve, but also does not allow system pressure independent characteristic curve formation.

Proceeding from this, the present invention seeks to propose an injector and a fuel injector, which overcome the disadvantages of the prior art and allow high variability in the formation of the injection rate curve.

This object is achieved by the features of claim 1 and of claim 7.

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

According to the invention, an injector for a fuel injection device is proposed. The injector may preferably be provided for use in a fuel injection device in the form of a common rail system, while the injector is generally intended for use with internal combustion engines in the form of gasoline or diesel engines, in particular large diesel engines and furthermore, in particular, vehicle engines, for example in off-road applications. or ship applications. The injector can be designed with a single-pressure accumulator or without such.

The injector has a control chamber, via which the stroke position or the stroke profile of a nozzle needle of a nozzle valve of the injector can be controlled. For this purpose, the pressure in the control room can be suitably adjusted, i. e. in a manner known per se, in the context of which the nozzle needle stands out from a nozzle needle seat when the pressure in the control chamber is relieved or, in the case of a corresponding pressure (build-up) in the control chamber, is forced towards or into the nozzle needle seat.

According to the invention, the injector comprises a first 2/2-way valve, in particular pilot valve (control valve or servo control valve), by means of which a first flow branch in communication with the control chamber is optionally interruptible. The first pilot valve may preferably be designed as a solenoid valve, ie open with a magnetic actuator, in particular when current supplied to the magnet assembly of the valve, in the de-energized state in particular spring-loaded occupy the closed position or hold. Alternatively, the first pilot valve z. B. be designed as a piezo valve.

In a preferred embodiment of the invention, the first flow branch may be an inflow branch or, alternatively, in another preferred embodiment, a branch branch in communication with the control chamber. As inlet branch (high pressure) of the first flow branch is provided to supply high pressure medium to the control chamber, including the inlet branch with a suitable source, for. B. can be connected to a rail or a single-pressure storage or can be. As a flow branch (low pressure), the first flow branch is intended to be able to relieve pressure on the control chamber, d. H. via discharged medium (leakage) from the same, which z. B. is traceable to a fuel supply via the flow branch. The first flow branch may be formed as at least one bore or (drilling) channel in the injector.

According to the invention, the injector further comprises a second 2/2-way valve, in particular pilot valve, by means of which a second flow branch (in the drain) or a discharge flow branch can be interrupted optionally. The second 2/2-way valve may be as described above for the first 2/2-way valve solenoid valve, d. H. with a Magnetaktuator, alternatively z. B. a piezo valve, woneben ever other valve designs are conceivable. By means of the thus configured injector, the first and second directional valve optionally and so far arbitrarily between a first (open / continuous) and a second (closed / locked) position can be switched, it is advantageously possible, the injector according to different characteristic interpretations regardless of the system pressure operate, or switch between different flow characteristics in operation. As a result of this embodiment of the injector according to the invention, the injection rate profile can advantageously be changed in a highly variable manner within the scope of injection processes. Furthermore, the injector can be provided with little structural effort. The 2/2-way valves, which can be made with small dimensions, can be easily integrated in the injector housing.

Preferably, the second flow branch is also provided as a flow branch in communication with the control chamber, i. e. as low-pressure or leakage branch. The second flow branch may in turn be designed as at least one bore or (drilling) channel and / or be provided for connection to a fuel supply. Furthermore, it can preferably be provided that the second flow branch is designed as a bypass branch. The second flow branch may in particular be guided around an outlet throttle in the first flow branch, the bypass branch preferably having a further outlet throttle.

In general, it is preferred within the scope of the invention that both the first flow branch and the second flow branch each have at least one throttle. About an interruption or opening of the respective branch, i. e. via the respective 2/2-way valve of the branch, thus each associated throttle cross-section can be blocked or enabled. This makes it possible to set different flow rates, in particular outflow rates, at the injector and to form the course of injection over the varying continuous throttle (total) cross-section.

The injector allows a broad spreading of the flow rate characteristic area with respect to an injector with only one pilot valve, so that a better minimum capacity and an optimized injector-to-injector scattering can be achieved.

Within the scope of the present invention, a fuel injection device is also proposed with at least one, in particular a plurality of injectors as described above, wherein the fuel injection device is designed to vary the injection rate profile in the course of successive injection events, in particular the steepness of the slope, by optional switching of the injection rate first and second 2/2-way valve of the respective injector. The injection device designed in this way is able to modulate a respective injection process or the injection characteristic advantageously load-dependent. A control device, in particular a control unit of the fuel injection device can be configured to switch by means of stored control schemes, curves or maps the first and second 2/2-way valves in response to the intended injection characteristic or by otherwise determining the einzusteuernden switching positions, eg. B. computerized.

The fuel injection device may in particular be designed to also reverse the first and / or second 2/2-way valve during an opening and / or closing operation of the nozzle valve, in particular in order to vary the speed of the nozzle needle during such an operation (active). A changeover between the valves or a reversal of a 2/2-way valve, z. B. just before taking off the Nozzle needle or during a nozzle needle movement, depending on the start and duration of the control, it is possible to allow almost any characteristics within the representable characteristics or operating ranges.

Preferably, the fuel injection device is further designed for operation, in which the control chamber is flushed by simultaneous opening of the first and second directional control valve via the inlet branch and a flow branch. Here, the first 2/2-way valve is arranged in the inlet branch and the other in the flow branch, wherein the branches each communicate with the control room. This operation is provided by means of the fuel injector for a state of the injector in which the nozzle valve is closed. In this case, it is particularly advantageously possible that the flushing of the control chamber can be carried out independently of the starting pressure of the injector (where the starting pressure is the pressure from which the injector can inject for the first time.) With a suitable design of the throttles, it is also possible to flush through it to realize at high injection pressures during engine operation.

Flushing is especially provided with the use of alternative fuels with a high tendency to form deposits to keep the injector leakage in increased motion when driving with small injection quantities (eg, idling, part-load, spark-ignition gas operation, and engine stall).

In general, the fuel injection device according to the invention is designed to be able to operate the injector system pressure independently according to different flow rate characteristics (interpretations) by means of the first and second 2/2-way valve, d. H. with a system pressure independent characteristic variability. When switching the valves without valve overlap, d. H. without short-circuit control leakage, higher opening and closing speeds of the nozzle needle can be achieved than with injectors with a 3/2-way valve.

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 can be realized individually for themselves or for several in any combination in a variant of the invention.

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

1 an example of a schematic diagram of a structure of an injector according to a first possible embodiment of the invention;

2a exemplary and schematic flow rate characteristics and 2 B associated injection rate curves, which are made possible by means of an injector or a fuel injection device according to the invention; and

3a to 3c each exemplarily and schematically a structural image of an injector according to further possible embodiments of the invention.

In the following description and the drawings, the same reference numerals correspond to elements of the same or comparable function.

1 shows schematically and exemplarily an injector 1 for a fuel injection device, in particular of a motor vehicle. The injector 1 has a housing 2 with a nozzle body in which a nozzle needle 3 a nozzle needle valve 4 is received axially displaceable. The nozzle needle 3 is against a valve seat 5 of the nozzle needle valve 4 biased, ie by means of a nozzle spring (not shown).

The nozzle needle 3 At least over a portion of the same is also surrounding a (ring) space 6 at the injector 1 formed, in which hochdruckbeaufschlagter fuel via a high-pressure bore (not shown) can be introduced, for. B. part of a rail or alternatively from a single pressure accumulator of the injector 1 , About the high-pressure fuel in the pressure chamber 6 can a force in the opening direction (arrow direction p _geo ) of the nozzle needle 3 be exercised, for which purpose it is suitably designed, in particular has a surface for the appropriate introduction of force. When opening the nozzle needle valve 4 can fuel out of the room 6 be discharged (injection process), ie over at least one injection hole of the nozzle.

To the nozzle needle 3 to be able to switch between the open and closed positions, ie the stroke position (axial displacement position) of the nozzle needle 3 to be able to control or adjust is in the injector 1 , In particular its nozzle body, continue to be a control room 7 provided, ie at a nozzle distal end 3a the nozzle needle 3 , which with a first flow branch 8th and a second flow branch 9 each of the injector 1 communicated. The control room 7 is by means of a sleeve body 10 formed or defined, in which the flow branches 8th and 9 lead into and in which the end 3a is recorded guided.

About the first flow branch 8th , which as a high-pressure or inlet flow branch 8th is provided, the control room 7 be subjected to high pressure or charged, ie via flow by means of high-pressure medium, ie fuel.

About the second flow branch 9 , which is provided as a low-pressure or drain-flow branch, the control chamber 7 be depressurized, ie via a fuel drain from the control room 7 , The second flow branch 9 for this purpose (on the outlet side) with a (leakage) collecting container of a fuel injection device, in particular a fuel supply 11 connectable, shown in dashed lines. The first 8th and the second 9 Flow branch are ever as (drilling) channel in the injector 1 executed.

The nozzle needle 3 is about debiting or debiting the control room 7 with high or low pressure open (stroke) or closed (return stroke). The position of the nozzle needle 3 as well as their speed when changing the positions depend on the pressures p _St and p _geo , s. 1 , The pressure p _geo denotes a summary of all pressures and (spring) forces acting on the needle, projected onto the area of the diameter of the nozzle needle 3 (∅-DN), at which also the control pressure p _St attacks.

In the first flow or inlet branch 8th is a first 2/2-way valve 12 arranged (valve _inlet in Table 1), by means of which the inlet branch 8th optionally (selectively) interruptible, ie between a (inlet side) high pressure port 13 of the flow branch 8th and the control room 7 ,

Between the first 2/2-way valve provided as a pilot valve 12 and the control room 7 is also a (inlet) throttle 14 (ZDr in Table 1) in the first flow branch or channel 8th arranged. The first 2/2-way valve 12 can be via a solenoid actuator of the valve 12 in conjunction with a valve's own spring load (compression spring) (um) to be controlled, ie by energizing / interrupting the energization.

In the second flow or drain branch 9 is a second 2/2-way valve 15 arranged (valve _drain in Table 1), by means of which the flow branch 9 optionally (selectively) interruptible, ie between a low pressure outlet 16 of the flow branch 9 and the control room 7 , Between the second 2/2-way valve provided as a pilot valve 15 and the control room 7 is also a (drain) throttle 17 (ADr in Table 1) in the second flow branch or channel 9 arranged. Like the first 2/2-way valve 12 can also be the second 2/2-way valve via a solenoid actuator of the valve 15 in conjunction with a valve's own spring load (compression spring) (um) are controlled, ie by energizing / interrupting the energization.

The thus configured injector 1 allows between at least two, in particular a plurality of characteristics (designs) A, B, C, sa 2a to switch back and forth, ie regardless of the prevailing system pressure. This can be done between two injection events or during an injection event.

One the injector 1 having fuel injector here preferably defines - via a suitable control scheme - an operating range for opening the nozzle needle 3 of the injector 1 which lies between a first operating limit, in particular for a slow opening, in which the first 12 and the second 15 2/2-way valve depending on the duration of the lifting operation) of the nozzle needle 3 are open and a second operating limit, in particular for a quick opening, in which the first 2/2-way valve 12 over the duration of the lifting process) of the nozzle needle 3 is closed and the second 2/2-way valve 15 over the duration of the lifting process) is open.

At the first opening operating limit is the short circuit control leakage via the control room 7 maximized over time due to the slowly declining pressure in the control room 7 becomes the nozzle needle 3 slowly out of the needle seat 5 raised. As a result, a flat edge in the injection rate profile (opening) can be generated.

At the second opening operation limit, which is accompanied by short-circuit control leakage, the opening speed of the nozzle valve 4 In contrast, maximized insofar as no simultaneous Filling or flow to the control room 7 during the discharge of the same takes place. Due to the rapid pressure drop, the nozzle needle 3 quickly out of the seat 5 lifted, ie a steep slope is created in the injection rate profile (opening).

Further preferably, the fuel injector defines by means of the injector 1 Via a suitable control scheme, an operating range for closing the nozzle needle 3 of the injector 1 which lies between a first operating limit, in particular for a slow closing, in which the first 12 and the second 15 2/2-way valve depending on the duration of the (return) stroke of the nozzle needle 3 are open and a second operating limit, in particular for a fast closing, in which the first 2/2-way valve 12 over the duration of the (re) stroke of the nozzle needle 3 is open and the second 2/2-way valve 15 is closed for the duration of the (re-) stroke.

At the first close operating limit is the short circuit control leakage via the control room 7 maximized over time due to the slowly increasing pressure in the control room 7 becomes the nozzle needle 3 slowly in the needle seat 4 guided. As a result, a flat edge in the injection rate profile (closing) can be generated.

At the second closing operating limit, which in turn is accompanied by short circuit control leakage, the opening speed of the nozzle valve 4 In contrast, maximized, insofar as no simultaneous emptying of the control room 7 over the second flow branch 9 during the load of the same over the first flow branch 8th he follows. Due to the rapid increase in pressure, the nozzle needle 3 quickly out of the seat 4 lifted, ie a steep slope in the injection rate (closing) are generated.

Table 1 below exemplifies possible operating states 1 to 4 of the injector 1 or a fuel injection device having this as a function of the valve positions of the valves 12 and 15 ie during injections. In the table v denotes a speed of the nozzle needle 3 , Condition nozzle property Valve V _inlet Valve V _drain Condition p _St , p _geo Main influence / dependence 1 cLOSED closed open to p _St = p _Sys> p _geo flushing open open p _St > p _geo p _{Sys.2 / 2-way} <start pressure p _{Sys.Double PV} ≠ f (start pressure) 2 open none. Tax class. to open p _St = p _leak control leakage open open p _St <p _geo f (ADr, ZDr) 3 to open fast (v _Ö1 ) to open p _St << p _geo v _Ö1 = f (ADr, p _Sys ) slowly (v _Ö2 ) open open p _St <p _geo v _Ö2 = f (ADR, ADR / ZDR, p _Sys) 4 Shut down fast (v _S1 ) open to p _St >> p _geo v _S1 = f (ZDr, p _Sys ) slow (v _S2 ) open open p _St > p _geo v _S2 = f (ADr, ADr / ZDr, p _Sys ) Table 1

Table 2 below further illustrates a relationship between the speed of the nozzle needle 3 when opening or closing the nozzle valve 4 which according to Table 1 each over the first 12 and second 15 2/2-way valve is adjustable (fast / slow), and one with each set characteristic A, B, C (see next 2a ) or an injection rate profile A1, B1, C1 (see next to it) 2 B ). curve Open the nozzle needle Close the nozzle needle Steep v _Ö1 (fast) v _S2 (slow) medium (1) v _Ö1 (fast) v _S1 (fast) medium (2) v _Ö2 (slow) v _S2 (slow) flat v _Ö2 (slow) v _S1 (fast) Table 2

In the injection rate according to 2 B , represented as a volume flow change V over time t, corresponds here to a steep flank to a fast nozzle needle opening or closing, a flat flank to a nozzle needle opening or closing that is slow relative thereto. By means of the first 12 and second 15 2/2-way valve of the injector 1 are apparent different flow characteristics (interpretations) A, B, C, each represented as a delivered (fuel) volume V over the time t in 2a , adjustable for injector operation. The characteristic A in 2a Corresponds here to the steep characteristic curve according to Table 2, the characteristic curve B with a mean characteristic curve (1) or (2) according to Table 2 and the characteristic curve C with the flat characteristic curve according to Table 2.

With the injector 1 it is also possible, within the characteristic curve steep (A) and flat (C), sa 2a , any other characteristic curves (B) for operation of the injector 1 represent or between characteristics by means of a suitable control of the 2/2-way valves 12 and 15 switch over (ie each system pressure independent). This operation can be controlled by an in-situ calibration.

3a now shows an injector 1 according to another preferred embodiment, wherein the annulus assembly 6 and the injector housing body 2 are not shown for reasons of simplification.

In contrast to the above according to 1 described injector 1 points the injector 1 according to 3a a first flow branch 8th on, which as a flow branch in communication with the control room 7 is formed. Next to it is also the second flow branch 9 as a flow branch in communication with the control room 7 provided. The control room 7 is here via an inlet flow channel 18 with an inlet throttle 14 (ZDr), which, in contrast to the above embodiment has no 2/2-way valve.

The first ones are visible 8th and second 9 Flow branches each from the control room 7 to a low-pressure outlet or leakage outlet 16a respectively. 16b of the injector 1 led, which with a fuel supply 11 is connectable, ie for leakage return, shown in dashed lines. In the first flow branch 8th is a first 2/2-way valve 12 arranged over which the first flow branch 8th is optionally interruptible, ie between the control room 7 and the outlet 16a , Between the valve 12 and the control room 7 is a first outlet throttle 17a (ADr1) in the first flow branch 8th arranged.

In the second flow branch 9 is a second 2/2-way valve 15 arranged over which the second flow branch 9 is optionally interruptible, ie between the control room 7 and the outlet 16b , Between the valve 15 and the control room 7 is still a second outlet throttle 17b (ADr2) in the second flow branch 9 arranged.

It should be noted that the first 8th and second 9 Flow branch alternatively to a single outlet 16 may be merged, for. B. also via a common branch section upstream of the throttles 17a and 17b with the control room 7 to be able to communicate.

By means of the injector 1 according to 3a It is also advantageously possible to be able to set different delivery rate characteristics for each system pressure independently in an injector operation. Optionally, the first flow branch 8th with the first outlet throttle 17a or the first throttle cross section via the first 2/2-way valve 12 be released, the second flow branch 9 with the second outlet throttle 17b or the second throttle cross section via the second 2/2-way valve 15 or both flow branches 8th respectively. 9 with respective throttle cross sections together, ie temporally overlapping. Where: p _{St, min} = f (ADr, ZDr) >> p _leak .

The 3b and 3c each show a further preferred embodiment of the injector 1 , wherein the first flow branch 8th ever before at 3a also as a flow branch in communication with the control room 7 is trained. In contrast to the embodiment described above. 3a is the second flow branch 9 hereby executed as a bypass in the process. For reasons of simplification, the respective annular space 6 at the nozzle needle 3 as well as the injector housing 2 again not shown.

At the injector 1 according to 3b is the control room 7 as before via an inlet flow channel 18 with an inlet throttle 14 (ZDr) can flow against, which flow channel 18 without 2/2-way valve is formed.

Visible is the first flow branch 8th which with the control room 7 (via its inlet or inlet side) communicates from the control room 7 turn to a low pressure outlet or leakage outlet 16 of the injector 1 led, which with a fuel supply 11 is connectable, ie for leakage return, shown in dashed lines. In the first flow branch 8th is the first 2/2-way valve 12 arranged as a main valve, via which the first flow branch 8th is optionally interruptible, ie between the control room 7 and the outlet 16 , Between the valve 12 and the control room 7 is a first outlet throttle 17a (ADr1) in the first flow branch 8th arranged.

The second flow branch or outflow branch 9 , which (via its inlet or inlet side) also with the control room 7 communicates is as a bypass to the first outlet throttle 17a formed circumferentially and opens downstream thereof and upstream of the first directional control valve 12 in the first flow branch 8th one. Here, in the second flow branch 8th the second 2/2-way valve arranged as a bypass valve, ie between the control room 7 and the confluence with the first flow branch 8th , About the second 2/2-way valve 15 is the second flow branch 9 optionally interruptible. In the second flow branch 9 is still a second outlet throttle 17b (ADr2), ie between the second 2/2-way valve and the junction.

It should also be noted that the first 8th and second 9 Flow branch alternatively via a common branch section upstream of the throttles 17a . 17b with the control room 7 to be able to communicate.

In this embodiment, the first pilot valve controls 12 the drain, ie via the outlet throttle 1 , The switchable second pilot valve 15 can increase the flow area here. In general, p _{st, min} = f (ADr, ZDr) >> P _leak . The second pilot valve 15 can be advantageously designed as a pressure-relieved valve.

By means of the injector 1 according to 3b It is also possible advantageous to be able to switch between different flow characteristics (designs) A, B, C in an injector operation, ie each system pressure independent. The second flow branch 9 However, in terms of its flow through the position of the first 2/2-way valve 12 dependent.

3c shows an injector 1 in which the control room 7 as before via an inlet flow channel 18 with an inlet throttle 14 (ZDr) can be flowed on, which in turn is formed without a 2/2-way valve.

Visible is the first flow branch 8th from the control room 7 turn to a low pressure outlet or leakage outlet 16 of the injector 1 led, which with a fuel supply 11 is connectable, ie for leakage return, shown in dashed lines. In the first flow branch 8th is the first 2/2-way valve 12 arranged as a main flow valve, via which the first flow branch 8th is optionally interruptible, ie between the control room 7 and the outlet 16 , Between the valve 12 and the control room 7 Here is a first, optionally provided drain throttle 17a (ADr1) arranged. A second outlet throttle 17b (ADr2) in the first flow branch 8th is downstream of the first 2/2-way valve designed as a main valve 12 between it and the outlet 16 arranged.

The second flow branch or outflow branch 9 communicates in this embodiment on the inlet side with the first flow branch 8th , wherein the second flow branch 9 from the first flow branch 8th between the first valve 12 and the second outlet throttle 17b branches. The second flow branch 9 is here as a bypass to the second outlet throttle 17b led around and flows downstream of the same back into the first flow branch 8th one. The second 2/2-way valve 15 is as before as a bypass valve in the second flow branch 9 arranged, ie between the junction and the junction. About the second 2/2-way valve is the second flow branch 9 optionally interruptible. In the second flow branch 9 is still a third outlet throttle 17c (ADr3), ie between the second 2/2-way valve 15 and the turnoff.

Also in this embodiment, the first pilot valve controls 12 the drain, ie via the outlet throttle 2 , The switchable second pilot valve 15 can increase the flow area here. Here again, in general, p _{st, min} = f (ADr, ZDr) >> p _leak . The second pilot valve 15 can be advantageously designed as a pressure relief valve, which can be depressurized during injection pauses.

By means of the injector 1 according to 3c It is also possible advantageous to be able to switch between different flow characteristics (designs) A, B, C in an injector operation, ie each system pressure independent. The second flow branch 9 However, in terms of its flow through again from the position of the first 2/2-way valve 12 dependent.

LIST OF REFERENCE NUMBERS

1

injector

2

casing 1

3

nozzle needle

3a

nozzle-far end 3

4

nozzle valve

5

Nozzle needle seat

6

pressure chamber

7

control room

8th

first flow branch

9

second flow branch

10

sleeve body

11

container

12

first 2/2-way valve

13

HP port

14

Inlet throttle

15

second 2/2-way valve

16, 16a, 16b

Low pressure port

17, 17a, b, c

Outlet throttle

18

Inlet flow channel

A, B, C

Discharge curves

A1, B1, C1

Injection rate course

ND

low pressure

HD

high pressure

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 19734354 A1 [0003]
• DE 19609799 C2 [0003]
• DE 102007010498 A1 [0004]
• DE 10132248 A1 [0004]
• DE 19742320 A1 [0005]

Claims (12)

Injector ( 1 ) for a fuel injection device, wherein the injector ( 1 ) a control room ( 7 ), via which the stroke position of a nozzle needle ( 3 ) of a nozzle valve ( 4 ) of the injector ( 1 ) is controllable, characterized in that the injector ( 1 ) a first 2/2-way valve ( 12 ), in particular pilot valve, comprises, by means of which a first flow branch ( 8th ) in communication with the control room ( 7 ) is optionally interruptible and a second 2/2-way valve ( 15 ), in particular pilot valve, by means of which a second flow branch ( 9 ) is optionally interruptible in the process. Injector ( 1 ) according to claim 1, characterized in that the first flow branch ( 8th ) an inflow branch or a flow branch in communication with the control room ( 7 ). Injector ( 1 ) according to claim 1 or 2, characterized in that the second flow branch ( 9 ) as a flow branch in communication with the control room ( 7 ). Injector ( 1 ) according to one of the preceding claims, characterized in that the second flow branch ( 9 ) is formed as a bypass branch, in particular around an outlet throttle ( 17a ; 17b ) in the first flow branch ( 8th ), wherein the bypass branch ( 9 ), in particular a further outlet throttle ( 17b ; 17c ) having. Injector ( 1 ) according to one of the preceding claims, characterized in that both the first flow branch ( 8th ) as well as the second flow branch ( 9 ) at least one throttle ( 14 . 17 ; 17a . 17b ; 17a . 17b . 17c ) exhibit. Injector ( 1 ) according to one of the preceding claims, characterized in that the injector ( 1 ) is operable according to a first flow rate characteristic (A, B, C) and to an operation according to at least one second flow rate characteristic (A, B, C) by means of the 2/2-way valves ( 12 . 15 ) is switchable, in particular under the same system pressure. Fuel injection device, characterized by an injector ( 1 ) or a plurality of injectors ( 1 ) according to any one of claims 1 to 6. Fuel injection device according to claim 7, characterized in that the fuel injection device for controlling the 2/2-way valves ( 12 . 15 ) of a respective injector ( 1 ) Is formed corresponding to a plurality of each system pressure independently adjustable injector flow characteristics (A, B, C). Fuel injection device according to claim 7 or 8, characterized in that the fuel injection device is provided during an injection event and / or between two injection events from a first to a further characteristic design of the respective injector ( 1 ) by means of its 2/2-way valves ( 12 . 15 ) switch. Fuel injection device according to one of claims 7 to 9, characterized in that the fuel injection device is formed, via a switching of the 2/2-way valves ( 12 . 15 ) of an injector ( 1 ) to allow a system pressure independent variable adjustment of the slope of the injection rate curve of a respective injection event. Fuel injection device according to one of claims 7 to 10, characterized in that the fuel injection device is designed, within an injection event, in particular during an opening or closing operation of the nozzle valve ( 4 ), the first ( 12 ) and / or second ( 15 ) 2/2-way valve of an injector ( 1 ) to switch over at least part of the respective operation period in the further position, in particular also intermittently. Fuel injection device according to one of claims 7 to 11 with an injector ( 1 ) according to one of claims 1 to 3 and 5 and 6, wherein the first flow branch ( 8th ) is a feed branch, characterized in that the fuel injection device for a state of the injector ( 1 ), in which the nozzle valve ( 4 ), defines a mode in which the control room ( 7 ) by the same time Opening the first ( 12 ) and second way valve ( 15 ) over the first flow branch ( 8th ) and the second flow branch ( 9 ) is rinsed.

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