EP2630359A1

EP2630359A1 - Injection device for a fluid

Info

Publication number: EP2630359A1
Application number: EP12704683.7A
Authority: EP
Inventors: Harald Schmidt; Richard Pirkl
Original assignee: Liebherr Machines Bulle SA
Current assignee: Liebherr Machines Bulle SA
Priority date: 2011-02-08
Filing date: 2012-02-08
Publication date: 2013-08-28
Also published as: RU2013141176A; WO2012107228A1; US20130319374A1; CH704454A1

Abstract

The present invention relates to an injection device (10, 110, 210, 310, 410) for a fluid, in particular for fuel, having at least one electric and/or electronic actuating element (25), having at least one valve (30), having at least one first throttle (40) and one second throttle (50), wherein the valve (30) can be switched into at least one first throttling position so as to activate the first throttle (40) and into at least one second throttling position so as to activate the second throttle (50), wherein the valve (30) is indirectly and/or directly coupled to the actuating element (25) such that, by means of an actuating process of the actuating element (25), the valve (30) can be indirectly and/or directly switched from the first throttling position into the second throttling position and/or vice versa. The present invention also relates to a common rail injection system, to an internal combustion engine, to a motor vehicle, to a ship and to a method for injecting a fluid.

Description

Injection device for a fluid

The present invention relates to an injection device for a fluid, in particular for fuel, as well as a common rail injection system, an internal combustion engine, a motor vehicle, a ship and a method for injecting a fluid.

Common rail injection, also known as accumulator injection, is an injection system for internal combustion engines in which a high-pressure pump brings the fuel to a high pressure level. The pressurized fuel fills a piping system that is constantly under pressure during engine operation. In common-rail injection systems, a common high-pressure common-rail accumulator with corresponding outlets is used to supply the cylinders with fuel.

FIG. 10 shows a common-rail injection system known from the prior art with an injection device 10 ', in which a needle 12 loaded with a spring 14 travels to at least one injection hole 18, which also the function of a throttle 18 can have lock and release. Fuel from the tank 60 is pumped via the high-pressure pump 70 into the rail reservoir 80 and held there under high pressure. The tank 60 is connected via the line 62 to the high-pressure pump 70.

The valve 27 'can be actuated via the engine control 20, also called ECU 20, and via the magnet 25 or magnetic switch 25. The valve 27 'is a 2/2-way valve and locks in the position shown in Figure 10, the return line 64 which leads from the injector 10' and the control chamber 11 of the injector 10 'to the tank 60. In the return line 64 downstream of the control chamber 11 and upstream of the valve 27 ', the outlet throttle 50' is arranged.

In the control room 11 stop elements 16 'are provided, on which the spring 12 can strike. Furthermore, the injection device 10 'has a so-called injection chamber 13 into which the fuel fluid to be injected can pass indirectly via the high-pressure pump 70 and the rail reservoir 80 via the lines 82 and 86. The control chamber 11 is further connected to the rail memory 80 via the line 82 and 84, in which an inlet throttle 40 'is arranged.

In connection with FIG. 10 and FIG. 11, the injection process will now be explained by way of example. FIG. 11 shows the stroke progression in percent [%] as a function of time, which is also plotted in percent [%], with 100% of the time corresponding to an injection process. FIG. 11 thus shows the rise ramp and the descending slope of the injection rate of the injection device 10 '.

When opening the valve 27 'by means of the ECU 20 and by means of the magnet 25, the needle 12 can be moved back in the direction of the stop 16' and thereby works against the force of the spring 14. This happens as long as the valve 27 'is opened, wherein the needle 12 at the end of the rise ramp at time t = 40% according to Figure 11 has reached the stop 16 '. The lifting height is then 100%. During this time, maximum injection takes place via the injection hole 18. The time t = 80% according to FIG. 11 is the moment in which the 2/2-way Valve 27 'is transferred by means of the ECU 20 and the magnet 25 in the closed position and the closing operation begins, so that the needle 12 is transferred due to the pressure build-up in the control chamber 11 back into the closed position.

However, this common rail system shown in Figs. 10 and 11 has the disadvantage that it does not allow an independent ramp-up and ramp-down of the injection rate. In addition, there may be quantity variations during the injection process. Although a fast closing and slower opening movement of the nozzle needle is possible, but this is only achieved via the additional throttle 40 'and the control chamber 1. The tightness of these components affects the switching process and is therefore subject to high variability.

Even with other, currently available common-rail injection systems, a dependence of the rising edge of the ratio of the throttles and is thus not freely selectable. However, it would also be desirable, also with regard to the improvement of emission values, to allow a further improvement of the combustion quality, for example in diesel engines, but also in gasoline engines with direct injection, in that the injection process can be carried out even more accurately.

It is therefore an object of the present invention to develop an injection device of the type mentioned in an advantageous manner, in particular to the effect that this allows an independent rise ramp and descending edge of the injection rate.

This object is achieved by an injection device with the features of claim 1. Accordingly, it is provided that an injection device for a fluid, in particular for fuel, is provided with at least one electric and / or electronic actuator, with at least one valve, with at least one first throttle and with at least one second throttle, wherein the valve in at least one first throttle position under activation of the Most throttle and at least a second throttle position under activation of the second throttle is switchable, wherein the valve is indirectly and / or directly coupled to the actuator that indirectly by means of an actuating operation of the actuator and / or directly the valve from the first to the second Throttle position is switchable and / or vice versa.

The fluid, in particular fuel, may for example be diesel fuel or gasoline. The injection device may in particular be an injection device for diesel engines or gasoline engines with direct injection. The injection device may comprise a spring-loaded needle, by means of which the drain is closable and / or releasable to an outlet throttle or an injection nozzle.

The at least one electrical and / or electronic actuator may be an electrically and / or electronically actuable actuator. In particular, the actuator may be a suitable actuator, by means of which the valve can be appropriately and suitably actuated.

In the at least one first throttle position can be provided that the valve releases a corresponding supply line of the first throttle, so that the fluid can flow through this throttle. The situation is similar in the second throttle position, in which the valve is connected such that a supply line to the second throttle is released so that the fluid can flow through the second throttle.

By means of a corresponding actuation, the valve can then be switched over from the first to the second throttle position and / or vice versa, or the valve can advantageously be switched from the first to the second throttle position and / or vice versa. In particular, it is provided in the first throttle position that no flow through the second throttle takes place and in the second throttle position is further provided in particular that no flow through the first throttle takes place. Such an injection device has the advantage that only a small leakage occurs and this only during the switching operation of the injection device. Furthermore, the throttles for the injection device are independently selectable. In particular, it is possible to independently select the throttles for the needle closing of the injection device and the needle opening of the injection device, if the injection device has corresponding needles for fluid metering of the injection process. In addition, it is no longer necessary to open z. B. these needles can be made by the ratio of the throttles. This dependence is advantageously overcome. In addition, it is now no longer necessary to define the closing of the needles only by a corresponding inlet throttle and the design of the needle spring. Rather, it is now possible to allow an independent rise ramp and falling edge of the injection rate. Due to the simple switching by means of the actuator responsible for the rise ramp throttle can be switched to the responsible throttle for the descent edge. This makes it possible to provide the throttles optimally dimensioned only for the task in question. Such an injection device makes it possible to work with the smallest forces. Corresponding actuators can therefore be provided easily and reliably.

It is further provided that the first throttle position is a throttle position for setting a descending edge of the fluid injection and / or that the second throttle position is a throttle position for setting a rise ramp for the fluid injection and / or that the first throttle is an inlet throttle by means of which at least the descending edge of the fluid injection is adjustable and / or that the second throttle is an outlet throttle, by means of which at least the rising ramp for the fluid injection is adjustable. In particular, it can be provided that in the first throttle position, the first throttle is released, so that adjusts the descending edge of the fluid injection. In this case, the slope or the gradient and thus the time length of the descent edge is significantly determined by the design of the first throttle. Next, in particular be provided that in the second throttle position, the second throttle is released, so that adjusts the rise ramp of the fluid injection. In this case, the slope and thus the time length of the rise ramp is largely determined by the configuration of the second throttle.

It is also conceivable that the valve has at least one high-pressure sealant.

In addition, it can be provided that the adjusting means indirectly and / or directly via a control and / or regulating means, in particular an ECU, controllable and / or regulated.

Furthermore, it can be provided that at least one 2/2-way valve is provided, which is connectable to and / or connected to a connecting line for the fluid, in particular a return line to a fluid tank.

It is also possible that at least one lever means and / or a connector means is provided, by means of which the valve is actuated, in particular pushing and / or pulling actuated. In particular, the lever means may be a simple lever and the connector means may in particular be a simple connector such as a linearly movable rod loadable by tension and compression, or a linearly movable rod which is loadable by tension and pressure.

Moreover, it is possible that the actuator is at least one magnetic means and / or at least one piezoelectric element and / or comprises. It is thus advantageously possible to allow a closing of, for example, the needle of an injection device, but also a corresponding switching to an opening of the needle directly via the coupling by means of a magnet. The magnet means may be a corresponding magnet or magnetic switch.

In addition, it is conceivable that by means of the magnetic means, the 2/2-way valve and the valve, in particular at the same time, can be actuated, wherein it is preferably provided that the valve can be actuated indirectly via the lever means. Furthermore, it can be provided that at least one throttle is arranged in a bypass line.

Advantageously, it is provided that the injection device is part of a common rail injection system.

Furthermore, the present invention relates to a common rail injection system having the features of claim 10. Thereafter, it is provided that a common rail injection system is provided with at least one injection device according to one of claims 1 to 9 or at least one injection device according to one of claims 1 to 9.

Furthermore, the present invention relates to an internal combustion engine having the features of claim 11. Thereafter, it is provided that an internal combustion engine with at least one injection device according to one of claims 1 to 9 and / or provided with at least one common rail injection system according to claim 10.

Furthermore, the present invention relates to a motor vehicle having the features of claim 12. Thereafter, it is provided that a motor vehicle, in particular a passenger car or a truck, with at least one injection device according to one of claims 1 to 9 and / or at least one Com- Rail injection system according to claim 10 and / or provided with at least one internal combustion engine according to claim 11.

In addition, the present invention relates to a ship with the features of claim 13. Thereafter, it is provided that a ship with at least one injection device according to one of claims 1 to 9 and / or with at least one common rail injection system according to claim 10 and / or is provided with at least one internal combustion engine according to claim 11. In addition, the present invention relates to a method having the features of claim 14. Thereafter, it is provided that in a method for injecting fluid by means of an injection device having at least one valve, with at least a first throttle and at least one second throttle, the valve of at least a first throttle position under activation of the first throttle in at least one second throttle position under activation of the second throttle and / or vice versa is switched.

Advantageously, it is provided that the method is carried out using an injection device according to one of claims 1 to 9.

Further details and advantages of the invention will now be explained in more detail with reference to an embodiment shown in the drawing.

Show it:

1 shows an inventive injection device of a common rail system in a schematic representation according to a first embodiment;

FIG. 2 shows an inventive injection device of a common rail system in a schematic illustration according to a second embodiment;

FIG. 3: an injection device according to the invention of a common rail system in a schematic illustration according to a third embodiment;

FIG. 4 shows an inventive injection device of a common rail system in a schematic illustration according to a fourth embodiment; Figure 5: an injection device according to the invention a common rail system in a schematic representation according to a fifth embodiment;

FIG. 6 shows a schematic representation of the embodiment shown in FIG. 5 in a first switching position in a schematic representation;

FIG. 7 shows a diagram of the stroke progression in percent relating to the switching position shown in FIG. 6;

FIG. 8 shows a schematic representation of the embodiment shown in FIGS. 5 and 6 in a second switching position;

FIG. 9 shows a diagram of the stroke progression in percent relating to the switching position shown in FIG. 8;

FIG. 10 shows a schematic representation of a known common rail injection system; and

FIG. 11: a diagram of the stroke progression in percent relating to the switching position shown in FIG.

1 shows a common rail injection system according to the invention with an injection device 10 according to the invention, which is an embodiment with a connector 24 with a guide of the valve body of the valve 30 as a changeover switch. Similar features which have already been described in connection with the prior art common rail system shown in FIG. 10 are given the same reference numerals, and in FIG. 10 comparable components and features are partially provided with dashed reference numerals for better discrimination. The actuator 25, here a standard pressing type magnet 25, is turned on by the ECU 20 at a predetermined time, and carries with it the valve body 37 of the valve 30 directly coupled via the connector 24. As a result, the low-pressure side valve surface of the valve 30 is released. The high-pressure chamber 15 of the nozzle needle 12 is connected via the outlet throttle 50 for the same and by opening the valve body 37 of the valve 30, the liquid can now flow. The nozzle needle 12 lifts according to the choke, with a, usually small speed to a z. B. to obtain flat rising injection rate.

The fast-moving magnet 25 is stopped at the end of its stroke and the formation of a further valve seat, the inflow to the high-pressure chamber 15 of the nozzle needle is stopped.

This is equipped with a further throttle 40 in the inflow and thus prevents the closing of the needle 12. If now the magnet 25 is switched off, this moves into its initial position and closes the low pressure bore. Thus, the high pressure chamber 15 is connected via the throttle 40 to the inlet 84 of the high pressure line and the needle 12 closes according to the selected throttle 40, in an advantageous embodiment very quickly and the injection rate of the injector 10 receives the desired property.

The throttle 40 is arranged in a bypass line 90, while the outlet throttle 50 is arranged in the interior of the injection device 10. The valve 30 has a valve body 37 which, in the embodiment shown here, is additionally provided with a high-pressure seal 35 or guided in a high-pressure seal 35.

In the embodiment shown in Figure 1, the connector 24 is U-shaped and can by appropriate operation, in particular pulling operation, by means of the magnet 25 to transfer the valve 30 in the first and second throttle position. In the figures 2 to 9 further embodiments of the injection devices 10, 110, 210, 310 and 410 according to the invention are shown, wherein the same or comparable features are provided with the same reference numerals.

FIG. 2 shows an injection device 10 in a further embodiment, wherein the embodiment shown in FIG. 2 is likewise an embodiment with a connector 24. Notwithstanding the embodiment shown in Figure 1, the connector 24 is rod-shaped and the inlet throttle 50 is also disposed in the interior of the injection device 110. The connector 24 can convert in particular by pressing operation of the valve 30 in the first and second throttle position.

FIG. 3 shows a further embodiment with an injection device 210, in which, similar to FIG. 1, an L-shaped connector 24 for pulling the valve 30 is provided. The valve 30 has a spherical valve body 37. The inlet throttle 40 is likewise arranged here in a bypass line 90.

FIG. 4 shows a further embodiment of the injection device 310, in which the magnet 25 actuates a lever 23 which is arranged outside or partially outside the injection device 310 and which is mounted by means of a bearing 22. The valve 30 with a spherical valve body 37 can release the inlet throttle 40 in the second throttle position and lock it in the first throttle position.

In the further embodiment of the injection device 410 shown in FIG. 5, a directly controlled changeover of the throttles takes place. In this case, a lever 23 is also provided, which is mounted by means of a bearing 22. In this case, the position is shown in Figure 5, in which the magnet 25 is turned off. Consequently, no fluid can flow out via the outlet throttle 50 and the drain line 64, since the valve 27 accordingly blocks the drain line 64. The valve 30 is in the first throttle position, so that via the supply line 84 and the throttle 40 of the High-pressure chamber 50 is printed by fluid flow such that the needle 12 closes the inlet to the throttle 18.

Figure 6 now shows the state in which the magnet 25 is turned on, so that a movement takes place in the direction X1, whereby the lever 23 moves the valve body 37 of the valve 30 in the second throttle position, so that the throttle 40 is blocked. At the same time, the valve 27 is connected in such a way that fluid can flow out of the high-pressure chamber 15 via the drain line 64 and via the throttle 50. As a result, the valve opens the needle 12. Then fuel from the rail memory 80 via lines 82 and 86 can flow through the injection chamber 13, leave the injector 410 via the throttle 18 and z. B. are injected into the corresponding cylinder of an internal combustion engine. The associated stroke progression in percent [%] over time in 00% is shown in FIG.

Figure 8 correspondingly shows the state in which the magnet 25 is turned off, so that a movement takes place in the direction X2. As a result, by means of the lever 23 of the valve body 37 of the valve 30 is again transferred to the first throttle position, so that now via the line 84 and the throttle 40 again high-pressure fluid flows into the high-pressure chamber 15, while due to the closing of the valve 27 now no fluid can flow out of the high pressure chamber 15 via the throttle 50 in the drain line 64. The associated stroke course is shown in FIG.

While in Figure 6, the needle 12 has completed a movement in the direction Xg _Uf , now takes place in Figure 8, a correspondingly opposite direction in the direction

Xzu-

Claims

Injection device for a fluid claims

1. Injection device (10, 110, 210, 310, 410) for a fluid, in particular for fuel, with at least one electric and / or electronic actuator (25), with at least one valve (30), with at least one first throttle (40 ) and with at least one second throttle (50), wherein the valve (30) in at least a first throttle position under activation of the first throttle (40) and in at least one second throttle position under activation of the second throttle (50) is switchable, wherein the valve (30) is indirectly and / or directly coupled to the actuator (25) such that by means of an actuating operation of the actuator (25) indirectly and / or directly the valve (30) is switchable from the first to the second throttle position and / or vice versa ,

2. Injection device (10, 110, 210, 310, 410) according to claim 1, characterized in that the first throttle position is a throttle position for the Ein Position of a descending edge of the fluid injection is and / or that the second throttle position is a throttle position for setting a rise ramp for the fluid injection and / or that the first throttle (40) is an inlet throttle (40), by means of which at least the descending edge of the fluid injection is adjustable and / or that the second throttle (50) is an outlet throttle (50), by means of which at least the rise ramp for the fluid injection is adjustable.

3. Injection device (10, 110, 210, 310, 410) according to claim 1 or 2, characterized in that the valve (30) has at least one high-pressure sealant (35) and / or that the actuating means (25) indirectly and / or directly via a control and / or regulating means (20), in particular an ECU (20), controllable and / or controllable.

4. Injection device (10, 10, 210, 310, 410) according to any one of the preceding claims, characterized in that at least one 2/2-way valve (27) is provided, which communicates with a connecting line (64) for the fluid, in particular a return line (64) to a fluid tank (60) is connectable and / or connected.

5. Injection device (10, 110, 210, 310, 410) according to any one of the preceding claims, characterized in that at least one lever means (23) and / or a connector means (24) is provided, by means of which the valve (30) is actuated , in particular pushing and / or pulling actuated.

6. Injection device (410) according to any one of the preceding claims, characterized in that the actuator (25) is at least one magnetic means (25) and / or at least one piezoelectric element and / or comprises.

7. Injection device (410) according to claim 6, characterized in that by means of the magnetic means (25), the 2/2-way valve (27) and the valve (30), in particular simultaneously, is operable, wherein it is preferably provided that the valve (30) indirectly via the lever means (23) is actuated.

8. Injection device (10, 210) according to any one of the preceding claims, characterized in that at least one throttle (40) in a bypass line (90) is arranged.

9. Injection device (10, 110, 210, 310, 410) according to any one of the preceding claims, characterized in that the injection device (10, 110, 210, 310, 410) is part of a common rail injection system.

10. Common rail injection system with at least one injection device (10, 110, 210, 310, 410) according to one of the preceding claims.

11. An internal combustion engine with at least one injection device (10, 110, 210, 310, 410) according to any one of claims 1 to 9 and / or with at least one common rail injection system according to claim 10.

12. Motor vehicle, in particular passenger car or truck, with at least one injection device (10, 110, 210, 310, 410) according to one of claims 1 to 9 and / or with at least one common rail injection system according to claim 10 and / or with at least one internal combustion engine according to claim 11.

13. Ship with at least one injection device (10, 110, 210, 310, 410) according to one of claims 1 to 9 and / or with at least one common rail injection system according to claim 10 and / or with at least one internal combustion engine according to claim 11th

14. A method for injecting fluid by means of an injection device with at least one valve (30), with at least one first throttle (40) and with at least one second throttle (50), wherein the valve (30) of at least a first throttle position under activation of the first throttle (40) in at least one second throttle position under activation of the second throttle (50) and / or vice versa is switched.

A method according to claim 14, characterized in that the method is carried out using an injection device (10, 110, 210, 310, 410) according to one of claims 1 to 9.