DE102017201262A1 - Accumulator injection system for internal combustion engines - Google Patents

Abstract

The accumulator injection system for the intermittent injection of high-pressure fuel into the combustion chambers of an internal combustion engine has a high-pressure conveying device (54) which feeds two external individual accumulators (72, 74) via a high-pressure feed line (60). From each of the external individual accumulators (72, 74), individual high-pressure lines (78) lead to the at least three associated injection units (10). The high-pressure lines (78) connect the external individual memories (72, 74) with the discrete storage chambers (14) of the injection units (10) without restriction. However, each of the individual accumulators (72, 74) is assigned a throttle device (76) which throttles the flow of the high-pressure fuel in both directions at least approximately equally. As a result, the required reproducible same injection operations of the injection valves (12) of the injection units (10) are achieved, although the line elements (80) to have a too low storage effect.

Description

The present invention relates to a storage injection system for the intermittent injection of high-pressure fuel into combustion chambers of an internal combustion engine.

A storage injection system of this type is in the earlier international patent application with the file number PCT / EP2015 / 072244 disclosed. This accumulator injection system has injection units each with an injection valve and a discrete storage chamber. The injection units are associated with throttle devices, which allow the flow of high-pressure fuel toward the respective injection unit unhindered and throttle in the opposite direction. Next, the storage injection system has at least two external individual storage, which feed their associated injection units with high-pressure fuel. Each of these individual storage devices is preceded by a further throttle device, which allows the flow of high-pressure fuel from a high-pressure delivery device into the external individual storage unhindered and throttles in the opposite direction. This allows high pressure fuel to flow to each injector during an injection event from both the associated discrete storage chamber and discrete storage chambers of other injection units and the external individual storages and from the high pressure conveyor. As a result, reproducible injection processes are possible with a small storage volume of the line elements.

Another storage injection system is from the document WO 2007/009279 A1 known. This high-pressure accumulator injection system for an internal combustion engine, preferably a diesel engine, has a number of injectors, which are connected via fuel lines to a high-pressure conveyor. Each injector, a storage chamber and a check valve associated with parallel bypass throttle are assigned. Thanks to the each injector associated check valve with parallel bypass throttle can be realized with the memory injection system even then stable and reproducible injection processes with a favorable pressure curve in each injection process when the discrete storage chambers have an unusually small volume. The storage chambers can be integrated in the housing of the injectors and account for external individual storage in the form of common rail.

Further fuel injection systems are from the document DE 10 2009 055 129 A1 . EP 1 469 189 A1 . EP 0 657 642 A2 . DE 37 00 687 A1 . US 2004/0112337 A1 and DE 102 38 951 A1 known.

It is an object of the present invention to provide a low-cost manufacturable storage injection system, which nevertheless ensures stable and reproproduzierbare injection operations with a favorable pressure curve in each injection process.

This object is achieved with a storage injection system, which has the features of claim 1.

The accumulator injection system for the intermittent injection of high-pressure fuel into combustion chambers of an internal combustion engine, in particular a diesel engine, has a high-pressure conveyor which supplies a number of injection units, each with an injection valve and a respective discrete storage chamber associated with high-pressure fuel.

As a rule, the high-pressure conveying device has a high-pressure pump, which is preferably driven mechanically and at a fixed speed ratio by the internal combustion engine.

The injection units are connected with each other and with the high-pressure conveyor via hydraulic line elements, which have too little storage effect to ensure the required reproducible same injection operations of the injectors.

The line elements have at least two external individual memories, preferably in the form of a rail, and a high-pressure feed line connecting them to the high-pressure conveyor. Furthermore, the line elements per injection unit to a high-pressure line, said high-pressure lines connect the discrete storage chambers of the at least three each of the external individual storage associated injection units individually with the associated external individual storage at least approximately unthrottled; that is, these compounds are free of throttle devices.

On the other hand, each of the external individual accumulators is assigned or preceded by a throttling device which exclusively develops throttling action by means of a throttle passage having a fixed geometry. In other words, the high-pressure fuel must flow in the direction of the high-pressure conveyor in the respective external individual memory and in the opposite direction through the throttle passage.

The throttle devices do not have a check valve upstream or in parallel with the throttle passage.

The advantage of the inventive storage injection system over that of the international patent application PCT / EP 2015/072244 known injection system is in particular that between the external individual memories and the discrete storage chambers of the injection units no throttle devices are present, in particular no flow of the high pressure fuel toward the injector at least approximately unhindered and throttling in the opposite direction throttling devices. Further, the upstream of the external storage devices throttle devices are simpler in construction than those according to the international patent application PCT / EP 2015/072244 ,

Preferably, the throttle passages of the throttle devices are formed identically; they therefore have the same geometry. This leads to a favorable production of the throttle devices and the same throttle characteristics of the throttle devices.

Preferably, the throttle devices throttle the flow of high pressure fuel in the direction of the high pressure conveyor into the respective external single memory and in the opposite direction at least approximately equal. In other words, the throttle devices have at least approximately the same throttling properties in both directions of flow.

Each external individual memory at least three injection units are assigned, that is, the latter are fed via the respective individual memory. It can be assigned to each of the external individual memory and four injection units.

The hydraulic line elements preferably have exactly two external individual memories. Thus, the injection units of internal combustion engines with two cylinder banks of three to four cylinders or combustion chambers or of a cylinder bank with six to eight cylinders or combustion chambers can be supplied with high-pressure fuel.

The high-pressure feed line preferably has a distributor element, in particular in the form of a T-piece, wherein a delivery section of the high-pressure feed line leads from the high-pressure conveyor to the distributor element and wherein a feed section of the high-pressure feed line leads from the distributor element to the assigned external individual store per external individual store. This allows a short overall length of the line elements.

Preferably, the throttle devices are installed in the feed sections, wherein the throttle devices in the immediate vicinity of the external individual memory, preferably at the input, in the immediate vicinity of the distributor element, preferably at its output, or may be located at a distance from the individual memories and the distributor element.

This offers the possibility, depending on the available space to arrange the throttle device at a suitable location.

Preferably, the throttle devices are incorporated in the distributor element itself or they are formed on the distributor element itself. This leads to a very space-saving embodiment.

It is possible to arrange the distributor element close to the high-pressure conveyor so that the conveyor section is considerably shorter compared to the feed sections. This embodiment can be particularly advantageous if the one of an external individual memory associated injection units of a cylinder bank of the internal combustion engine and the other external individual memory associated with injection units of another cylinder bank of the internal combustion engine are assigned.

However, it is also possible to arrange the distributor element close to the external individual store, so that the conveyor section is longer in comparison with the feeder sections. This can be advantageous if the injection units assigned to the external individual memory are assigned to the same cylinder bank.

However, it is also possible to arrange the distributor element directly at a high-pressure outlet of the high-pressure conveyor such that a feed section of the high-pressure feed line leads from the distributor element to each external individual store.

In this embodiment, the throttle devices are preferably installed in the distributor element or formed on this, which contributes to a particularly space-saving embodiment.

However, it is also possible, in this embodiment, the throttle devices in the immediate vicinity of the distributor element, preferably at the output or in the immediate vicinity of the external individual memory, preferably to arrange at the input. Of course, it is also possible, the throttle devices at a distance to place the high-pressure conveyor and the external individual memories.

Depending on the given geometric arrangement of the combustion chambers of the internal combustion engine, the options given allow an optimal embodiment of the line elements to be selected.

It should be mentioned at this point that it is quite possible to allocate a different number of injection units to the external individual memories, for example one injection unit for the three external injection units and the other four.

Further, it is possible to have a second set of injection units - d. H. other injection units - and hydraulic pipe elements - d. H. provide further hydraulic line elements - which are formed according to the above possibilities and fed by the same high-pressure conveyor. As a result, the accumulator injection system for internal combustion engines with a larger number - that is, twelve to sixteen - cylinder or combustion chambers suitable.

It is even conceivable, with an embodiment similar to the embodiment just described, to supply an internal combustion engine with twenty cylinders-for example a V20 engine with two banks of ten cylinders or combustion chambers-with high-pressure fuel. In this case, the two sets of hydraulic line elements would either have three external individual memories, with two of these external individual memories each supplying three injection units and one of these external individual storage supplies four injection units with high-pressure fuel, or two external individual storage units, each of these external individual storage units each having five injection units Supplied high-pressure fuel.

Preferably, the distributor element has a distributor block, to which an input - for connecting the distributor block to the high-pressure conveyor device - and outputs - for connecting the distributor block to the external individual memories - are formed. From the bottom of the entrance runs in the manifold block blind hole, the hole bottom is preferably rounded, for example, hemispherical shaped. From the bottom of each output goes from a transverse bore, which opens into the blind hole, preferably at a distance to the hole bottom. Each of the cross holes forms a throttle throat. Each throttle passage has a narrowest flow cross-section, which preferably lies directly at the blind hole.

It should be noted that the narrowest cross-section can also be over part of the length of the transverse bore or over its entire length.

It is also possible to conically form the throttle passages and thereby obtain different throttle properties in a certain degree in both directions of flow.

The flow cross section of the blind hole is greater than the sum of the narrowest flow cross sections of the throttle passages.

Preferably, the transverse bores are perpendicular to the blind hole.

The input and the outputs are preferably designed for Hochdruckschraubverbindung. For this purpose, they preferably have connection hole bores with an internal thread formed on the distributor block, wherein conical high-pressure sealing surfaces are formed in the bottom of the connection blind bores, from which the blind bore or the transverse bores run.

The throttle devices must have a cross-section which allows the pressure in the external single memory to recover from a "first" injection to a "second" injection at short intervals. In injections with a greater time interval, the pressure in the relevant external individual memory then recovers faster than necessary and remains at its maximum, possibly with small residual pressure oscillations.

The invention will be explained in more detail with reference to embodiments shown in the drawing. It shows purely schematically:

1 in longitudinal section an injection unit with an injection valve and a discrete storage chamber arranged in the same housing, but without throttle device;

2 a first embodiment of the storage injection system with two external individual storage, each of which feed at least three injection units and are supplied via a distributor element arranged therein throttle devices by means of the high-pressure conveyor with high-pressure fuel;

3 a second embodiment of the storage injection system with two external individual storage, each of which feed at least three injection units and are supplied by the high-pressure conveyor with high-pressure fuel, wherein on the input side of each individual memory, a throttle device is provided;

4 a third embodiment of the storage injection system with two external individual storage, each feeding at least three injection units and are supplied by the high-pressure conveyor with high-pressure fuel, wherein near the high-pressure conveyor a distributor element is arranged with throttle devices integrated therein;

5 a fourth embodiment of the storage injection system with two mirrored arranged storage injection systems according to 2 ;

6 with a simulation calculation of the embodiment according to 2 with four injection units per external single memory calculated pressure curves at full load injections into the cylinders or combustion chambers one to four, immediately before the nozzle injection ports (blind hole pressure) and in the middle of the associated external single memory;

7 in the same representation as 6 the corresponding pressure curves for the cylinders five to eight; and

8th in cross-section an embodiment of a distributor element.

In the description of the figures, the same reference numerals are always used for the same or equivalent parts.

1 shows in longitudinal section an injection unit 10 , which is an injection valve 12 and a discrete storage chamber associated therewith 14 includes. In the embodiment shown, the components of the injection valve 12 and the discreet pantry 14 in a common housing 16 arranged. The structure and operation of the injection unit 10 is the same as this in the document WO 2007/009297 A1 is disclosed. The housing 16 is shown simplified in two parts, wherein there is a housing part 18 in which the discrete storage chamber 14 is formed and in which an electromagnetic actuator assembly 20 is included. Next, the housing 16 a nozzle body 22 on, which frontally on the housing part 18 is present and by means of a union nut 24 is held tightly to this. On the nozzle body 22 facing away from the housing, the housing 16 or the housing part 18 a high pressure fuel inlet 26 (without throttle device), which in the discrete storage chamber 14 empties.

From the discrete storage chamber 14 runs in the longitudinal direction of the housing 16 through the housing part 18 through a fuel channel 28 , which is in the nozzle body 22 continues at an angle to the longitudinal direction and into a longitudinal recess 30 in the nozzle body 22 empties.

In the longitudinal recess 30 is located in a known manner, a needle-shaped injection valve member 32 , which by means of a compression spring 34 with one towards an injector seat 36 directed to directed closing force.

The with the injection valve member 32 cooperating, conically shaped injector seat 36 is on the nozzle body 22 educated. Downstream of the injector seat 36 has the nozzle body 22 a spherical segment-shaped blind hole, from which a nozzle 38 forming nozzle injection ports 40 through the wall of the nozzle body 22 run. In the assembled state, the nozzle injection openings open 40 in the relevant combustion chamber of the internal combustion engine.

On the other hand, the compression spring is supported 34 on a sleeve 42 in which one at the injection valve member 32 trained, double-acting piston 44 is guided in close sliding fit. The piston 44 and the sleeve 42 limit a control room 46 a hydraulic control device 48 , to which in the embodiment shown, an intermediate valve 50 belongs.

For an injection of high-pressure fuel into the combustion chamber of the internal combustion engine, the actuator assembly 20 excited, leaving the control room 46 Fuel in a fuel return 52 can flow out and thereby the pressure in the control room 46 drops. This has the consequence that the injection valve member 32 from the injection valve seat 36 is lifted and high pressure fuel through the nozzle injection ports 40 is injected into the combustion chamber. To complete the injection process, the actuator assembly 20 de-energized, causing the control room 46 from the fuel return 52 is disconnected and via the intermediate valve 50 Fuel in the control room 46 flows in to the control room 46 to increase the pressure. As a result, the injection valve member 32 again in contact with the injection valve seat 36 brought, which ends the injection process.

The dimensioning of the discrete storage chamber 14 is also in the document, for example WO 2007/009279 A1 disclosed. The disclosure in question is incorporated by reference in the present text.

Injection units of a different design, in particular injection valves of a different design, can also be used for the accumulator injection system according to the invention.

2 shows a first embodiment of an inventive storage injection system. This has, like any other embodiment also, a high-pressure conveyor 54 on. As a rule, the high-pressure conveyor 54 a high-pressure pump, which is driven by the internal combustion engine mechanically and at a fixed speed ratio. Inside the high-pressure conveyor 54 or the high-pressure pump may be a high pressure compensating volume and additionally a pressure sensor for detecting and regulating the system high pressure.

At a high pressure outlet 56 the high-pressure conveyor 54 is a promotional section 58 a high-pressure feed line 60 fastened for example by means of a high pressure fitting.

Andernends is the conveyor section 58 to the entrance 62 a designed as a T-piece distributor element 64 connected. To the two exits 66 of the distributor element 64 is ever a food section 68 the high-pressure feed line 60 connected, which food sections 68 at the other end to the entrance 70 an assigned external single memory 72 respectively 74 are connected. In the exemplary embodiment shown, the individual memories 72 and 74 designed in the style of a rail.

In the distributor element 64 is at each of the two outputs 66 a throttle device 76 in the form of a throttle passage 77 formed with a cross-sectional constriction. The throttle devices 76 thus point in the direction of the high-pressure conveyor 54 into the respective external single memory 72 . 74 Same throttle properties as in the opposite direction. The two throttle devices 76 are identical.

Each of the individual memories 72 . 74 is thus a separate throttle device 76 assigned.

Each of the two individual memories 72 . 74 feeds via a high pressure line 78 three injection units 10 as shown by solid lines. At this point it should be noted that the individual memory 72 . 74 with the discrete storage chambers 14 the injection units 10 are connected free of a throttle.

As indicated by dashed lines, one of the individual memories 72 . 74 or can the two individual memories 72 . 74 a fourth injection unit 10 supply with high-pressure fuel.

The external single memories 72 . 74 with the high pressure conveyor 54 connecting high-pressure feed line 60 , that means the conveyor section 58 , the distributor element 64 and the food sections 68 , as well as the external single memory 72 . 74 and the high pressure lines 78 form hydraulic pipe elements 80 which the injection units 10 with each other and with the high-pressure conveyor 54 connect.

These pipe elements 80 have a too low storage effect to the required reproducible same injection operations of the injectors 12 to ensure. Surprisingly enough, however, as simulation calculations show - to which in connection with the 6 and 7 will be discussed in more detail - the two throttle devices 76 to the required reproducible same injection operations of all injectors 12 , even under full load, to ensure.

The in the 2 embodiment shown is for a. Internal combustion engine with a cylinder bank with six, seven or eight cylinders or combustion chambers and suitable for an internal combustion engine with two cylinder banks à three or four cylinders or combustion chambers.

As an indication of the dimensioning of the throttle devices 76 the following example is mentioned: with an injection quantity of about 1,500 mm ³ per injection and a engine speed of about 1,000 revolutions per minute of a four-stroke engine, the narrowest diameter cross-section of each of the throttle devices is about 1.5 mm, each external single memory 72 . 74 feeds four injection units.

That the hydraulic pipe elements 80 have too low storage effect to the required reproducible same injection operations of the injectors 12 can be easily determined on an equipped with the storage injection system internal combustion engine that a trial run at remote throttle devices 76 is driven; while a restless run will be noted.

At the in 3 shown embodiment of the storage injection system directs the conveyor section 58 the high pressure fuel from the high pressure conveyor 54 also to a distribution element 64 , which is designed as a tee, but no throttle devices 76 having. From this distributor element 64 leads to each of the two individual memories 72 . 74 a food section 68 , in each of which a throttle device 76 is installed. In the embodiment shown, the throttle devices are located 76 in the immediate vicinity of the entrance 70 the single memory 70 . 74 ,

Same as in the 2 embodiment shown lead from the individual memories 72 . 74 to the associated three or four injection units 10 the high pressure lines 78 , which free of chokes the individual memory 72 . 74 with the discrete storage chambers 14 the injection units 10 connect.

The in the 4 shown embodiment of the storage injection system is that according to 2 similar, the only difference being that the length of the conveyor section 58 is short and the distributor element 64 with the throttle devices 76 close to the high pressure outlet 56 the high-pressure conveyor 54 located. The food sections are correspondingly longer 68 to the individual memories 72 . 74 educated.

It is also possible on the conveyor section 58 to dispense and the distributor element 64 at the high pressure outlet 56 the high-pressure conveyor 54 to arrange.

For the sake of completeness it should be mentioned that this also applies to different embodiments with a distributor elements 64 without throttle device 76 the case may be.

The distributor element 64 could also be an integral part of a cylinder head element of the high-pressure pump designed as a high-pressure conveyor 54 be. Also in this case would be no funding section 58 present and the high pressure feeders 60 would be through the dining sections connected to the cylinder head element 68 educated.

5 shows with solid lines inventive storage injection systems for a twelve-cylinder diesel engine, which is preferably designed as a V12 engine. The high-pressure conveyor 54 feeds two in the 2 shown and mirror-symmetrically arranged storage injection systems, wherein of the high-pressure conveyor 54 to each of the two distribution elements 64 with the throttle devices 76 a separate conveyor section 58 the line elements 80 leads. In addition, the description of the 2 directed.

It should also be mentioned the possibility, in this arrangement, the conveyor sections 58 to train for different lengths.

Of course, it is also possible, analogous to the embodiment according to 5 two each in the 3 and 4 shown storage injection systems by means of a single high-pressure conveyor 54 to feed and thus to operate a twelve-cylinder internal combustion engine.

As in 5 indicated with dashed lines, the storage injection system can also be formed for an internal combustion engine with sixteen cylinders and thus sixteen combustion chambers. It should be noted that it is also possible to operate with the storage injection system, an internal combustion engine with thirteen, fourteen or fifteen cylinders.

In the case of the inventive spoke injection system, the pressure oscillations, which are produced by the injections into the individual memories, are in the simplest way 72 . 74 and from the high pressure conveyor 54 into the pipe elements 80 be brought in, kept separated from each other, which causes a significantly increased accuracy of the uniformity of the individual injections.

This is shown in the diagrams of the 6 and 7 illustrated pressure curves of an eight-cylinder accumulator injection system according 2 , This means that to each of the two individual memory 72 . 74 four injection units 10 are connected.

6 shows the pressure curves of the high-pressure fuel for the cylinders or combustion chambers 1, 2, 3 and 4 with the line patterns indicated in the legend. The so-called "blind hole pressure" is the pressure in the room - see 1 - between the injector seat 36 and the nozzle injection ports 40 , With "rail pressure 1" is the pressure curve in the associated individual memory 72 specified.

7 represents the corresponding pressure curves for the cylinders 5, 6, 7 and 8, that is, the corresponding injection units 10 and the pressure curve in the associated individual memory 74 represents.

From the diagrams in the 6 and 7 It can be seen that the injection sequence for each four a single memory 72 . 74 associated injection units 10 takes place at different intervals. This is because the firing order makes it so necessary. Placing the two diagrams on top of each other results in an injection or ignition sequence for all injection units 10 with the same time intervals, which generates as far as possible even torque output at the output of the crankshaft of the internal combustion engine. It can also be seen that the pressure profiles calculated using a computer model are the same in all injection units 10 run virtually identical and thus for all combustion chambers and corresponding injection units 10 identical conditions are given.

8th shows in cross section a distributor element 64 with throttle devices formed thereon 76 , Such a distribution element 64 can at the in the 2 . 4 and 5 shown embodiments of the storage injection system can be used.

The T-piece distributor element 64 has a cuboid distribution block 82 of steel, for example. At an input side of the manifold block 82 is an entrance 62 and at two opposite and adjacent to the input side output sides is ever an output 66 educated. The entrance 62 and the outputs 66 are the same shape and oriented in a T-arrangement to each other.

The entrance 62 and the outputs 66 are the same. They have a connecting blind bore formed from the input side or the output sides 84 with internal thread to the conveying section via a well-known high-pressure screw 58 or the food sections 68 the high-pressure feed line 60 to join. An otherwise level floor 86 the connection blind holes 84 has a conically tapered sealing surface in the center 88 , ie a high pressure sealing surface.

From the sealing surface 88 and thus the ground 86 of the entrance 62 runs centric to the connection blind hole 84 and the sealing surface 88 defined axis a blind hole 90 constant diameter, with the hole bottom 92 the blind hole 90 hemispherical rounded to from high-pressure fuel in the manifold block 82 to minimize generated stresses.

From the sealing surface 88 and thus the ground 86 the outputs 66 runs centric to the relevant blind blind holes 84 and the respective sealing surfaces 88 defined, the axis crossing at right angles transverse axis each have a transverse bore 94 , which are at a distance to the hole bottom 92 in the blind hole 90 lead.

These cross holes 94 form the throttle passages 77 the respective throttle devices 76 ,

Starting from the sealing surfaces 88 the transverse bores taper 94 with a smaller cone angle than the sealing surfaces 88 up to a narrowest flow cross-section 96 , which in one to the blind hole 84 reaching, the throttle passage 77 forming, circular cylindrical portion of the transverse bore is maintained.

Due to the symmetrical structure are the throttle characteristics of the two throttle devices 76 identical.

As an example, mention that for one already related above 2 mentioned four-stroke engine which the throttle passages 77 forming, circular cylindrical sections have a diameter of 1.5 mm and a length of 10 mm (or less).

If the line elements 80 , in a known manner, must be executed double-walled, for example, for marine applications are in the manifold block 82 Leak detection holes 98 attached, each from the ground 86 the connection blind holes 84 , radially outside the sealing surfaces 88 , go out and the outputs 66 with the entrance 62 connect.

The cross section of the blind hole 90 is greater than the sum of the two narrowest flow cross sections 96 ,

Next are at the manifold block 82 two mounting holes 100 attached, which is the attachment of the manifold block 82 serve on the structure of the internal combustion engine by means of screws.

In the 2 to 5 are the throttle passages 77 as continuously tapered and widening constrictions indicated. In the 8th they are shown as a circular cylindrical portion of a bore. However, it is also possible, the throttle devices 76 as a disc with a throttle passage 77 form forming hole or as a diaphragm. It is also possible, depending on the desired different throttle properties in both flow directions, to design the throttle passages as tapering or widening.

As with the dashed line 102 indicated, it is possible the distributor element 80 , or the distribution block 82 at the high pressure outlet 56 at the high pressure conveyor 54 to arrange. The blind hole 90 is then directly with the high pressure outlet 56 connected.

In all embodiments, the throttle passages 77 a solid geometric shape.

For the sake of completeness it should be mentioned that for all shown embodiments similar throttle ratios, as in connection with 2 indicated, can serve.

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

• EP 2015/072244 [0002, 0013, 0013]
• WO 2007/009279 A1 [0003, 0054]
• DE 102009055129 A1 [0004]
• EP 1469189 A1 [0004]
• EP 0657642 A2 [0004]
• DE 3700687 A1 [0004]
• US 2004/0112337 A1 [0004]
• DE 10238951 A1 [0004]
• WO 2007/009297 A1 [0048]

Claims (17)

Storage injection system for the intermittent injection of high-pressure fuel into combustion chambers of an internal combustion engine, with a high-pressure conveyor ( 54 ), a number of the high-pressure conveyor ( 54 ) supplied with high-pressure fuel, each an injection valve ( 12 ) and a discrete storage chamber ( 14 ) having injection units ( 10 ) and with the injection units ( 10 ) with each other and with the high pressure conveyor ( 54 ) connecting hydraulic line elements ( 80 ), which have too little storage effect to the required, reproducible same injection operations of the injectors ( 12 ), the line elements ( 80 ) at least two external individual memories ( 72 . 74 ) and one with the high pressure conveyor ( 54 ) connecting high-pressure feed line ( 60 ) and per injection unit ( 10 ) a high pressure line ( 78 ), which high pressure lines ( 78 ) the discrete storage chambers ( 14 ) of the at least three of each of the external individual memories ( 72 . 74 ) associated with injection units ( 10 ) individually with the relevant external individual memory ( 72 . 74 ) connect at least approximately unthrottled, and wherein each of the individual memories ( 72 . 74 ) an exclusively throttling action unfolding throttle device ( 76 ) with a fixed geometry throttle passage ( 77 ) is connected upstream. Storage injection system according to claim 1, characterized in that the throttle passages ( 77 ) of the throttle devices ( 76 ) are formed identically. Storage injection system according to claim 1 or 2, characterized in that the throttle devices ( 76 ) in the direction of the high pressure conveyor ( 54 ) into the relevant external individual memory ( 72 . 74 ) and in the opposite direction have at least approximately the same throttle properties. Storage injection system according to one of claims 1 to 3, characterized in that the high-pressure feed line ( 60 ) a distributor element ( 64 ), one of the high pressure conveyor ( 54 ) to the distributor element ( 64 ) leading section ( 58 ) and per external single memory ( 72 . 74 ) one from the distributor element ( 64 ) to the assigned external individual memory ( 72 . 74 ) leading food section ( 68 ) having. Storage injection system according to claim 4, characterized in that the throttle devices ( 76 ) in the food sections ( 68 ) are arranged. Storage injection system according to claim 5, characterized in that the throttle devices ( 76 ) in the immediate vicinity of the external individual memory ( 72 . 74 ), preferably at the entrance ( 70 ) are located. Storage injection system according to claim 5, characterized in that the throttle devices ( 76 ) in the immediate vicinity of the distributor element ( 64 ), preferably at its exit ( 66 ) are located. Storage injection system according to claim 4, characterized in that the throttle devices ( 76 ) in the distributor element ( 64 ) are incorporated or formed on this. Storage injection system according to one of claims 4 to 8, characterized in that the conveyor section ( 58 ) compared to the food sections ( 68 ) is shorter. Storage injection system according to one of claims 4 to 8, characterized in that the conveying section ( 58 ) compared to the food sections ( 68 ) is longer. Storage injection system according to one of claims 1 to 3, characterized in that the high-pressure feed line ( 60 ) on a high-pressure outlet ( 56 ) of the high pressure conveyor ( 54 ) arranged distributor element ( 64 ) and per external single memory ( 72 . 74 ) one from the distributor element ( 64 ) to the assigned external individual memory ( 72 . 74 ) leading food section ( 68 ) having. Storage injection system according to claim 11, characterized in that the throttle devices ( 76 ) in the distributor element ( 64 ) are incorporated or formed on this. Storage injection system according to claim 11, characterized in that the throttle devices ( 76 ) in the immediate vicinity of the distributor element ( 64 ), preferably at its exit ( 66 ) are located. Storage injection system according to claim 11, characterized in that the throttle devices ( 76 ) in the immediate vicinity of the external individual memory ( 72 . 74 ), preferably at the entrance ( 70 ) are located. Storage injection system according to one of claims 1 to 14, characterized in that the line elements ( 80 ) exactly two external individual memories ( 72 . 74 ) exhibit. Storage injection system according to claim 8 or 12, characterized in that the distributor element ( 64 ) a distribution block ( 82 ), on which an input ( 62 ) and outputs ( 66 ) are formed by a floor ( 86 ) of the input ( 62 ) a blind hole ( 90 ) with a preferably rounded perforated bottom ( 92 ) as well as from a ground ( 86 ) each output ( 66 ) one in the blind hole ( 90 ) transverse bore ( 94 ), and the transverse bores ( 94 ), preferably immediately after the blind hole ( 90 ), a narrowest flow area ( 96 ) of the relevant restrictor passage ( 77 ), wherein the flow cross section of the blind hole ( 90 ) is greater than the sum of the narrowest flow cross sections ( 96 ) of the throttle passages. Storage injection system according to one of claims 1 to 16, characterized by a further number of the high pressure conveyor ( 54 ) supplied with high-pressure fuel, depending on a further injection valve ( 12 ) and a further discrete storage chamber ( 14 ) further injection units ( 10 ) and with the other injection units ( 10 ) with each other and with the high pressure conveyor ( 54 ) connecting further hydraulic line elements ( 80 ), which have too little storage effect to the required, reproducible same injection operations of the other injectors ( 12 ), whereby the further line elements ( 80 ) at least two further external individual memories ( 72 . 74 ) and one with the high pressure conveyor ( 54 ) connecting another high-pressure feed line ( 60 ) as well as per further injection unit ( 10 ) another high-pressure line ( 78 ), which further high-pressure lines ( 78 ) the further discrete storage chambers ( 72 . 74 ) of the at least three of each of the further external individual memories ( 72 . 74 ) associated further injection units ( 10 ) individually with the respective further external individual memory ( 72 . 74 ) connect at least approximately unthrottled, and wherein each of the further individual memory ( 72 . 74 ) another throttle device ( 76 ), which exclusively a geometrically fixed throttle passage ( 77 ) having.

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