A FUEL INJECTION VALVE ARRANGEMENT FOR INTERNAL COMBUSTION ENGINE

Description

Technical field

[0001] The present invention relates to a fuel injection valve arrangement for internal combustion engine according to the preamble of claim 1. More specifically the invention relates to a fuel injection valve arrangement comprising a fuel injector body, a nozzle needle arranged longitudinally movably in a first end of the fuel injector body and surrounded at least partially by a needle chamber, the fuel injection valve arrangement further comprises a flow fuse valve unit having an inlet in flow communication with a high-pressure accumulator and an outlet in flow communication with the needle chamber, and the flow fuse valve unit is arranged to allow predetermined amount of fuel to flow in a direction from the inlet of the flow fuse valve unit to the outlet of the flow fuse valve unit.

Background art

[0002] The operational requirements of combustion piston engines are becoming more and more demanding and thus the accuracy and reliability of injecting adequate amount of fuel into combustion cylinder is ever more important. In diesel engines, the fuel is injected from a fuel injector into the cylinder of the engine such that with eddies of air is achieved a good mixture of fuel and combustion air and combustion. Usually, the fuel injection is done by using a common rail fuel injection system wherein the provision of pressure and the fuel injection are functionally separated from each other. By means of at least one high pressure fuel pump, the fuel is fed into a common pressure accumulator where from the fuel is led through separate pipes into the fuel injector of each cylinder. Thus the fuel injector operates in harsh circumstances and under high and varying pressure levels. Therefore, it is important to use reliable and long-lasting fuel injectors so as to run the engine smoothly.

[0003] Due to the harsh circumstances, malfunctions may occur in fuel injection operation. When a malfunction in fuel injection operations occur, the pressure level in the fuel injector may be increased significantly. This may cause more damages to the fuel injector but it may also cause challenges for maintenance operations. Therefore, it is highly desirable that the pressure level can be reduced from the fuel injector efficiently and safely, for example, in case of unexpected shut down. Strategies to reduce the pressure level safely and efficiently in the fuel injector body may, however, lead to complex structures in the fuel injectors and increase amount of parts needed in the fuel injector. This may also increase the amount of uncertainty of how well different parts will last in harsh circumstances. Furthermore, the fuel injection systems may become more space consuming and technically complicated. Thus it is desirable to obtain fairly simple but long-lasting valve arrangement that provides a safe way to stabilize pressures in the fuel injector body.

[0004] WO 2013153010 A1 discloses an injector of a modular common-rail fuel injection system with a built in high-pressure accumulator. The fuel injection system comprises a throughflow limiter for limiting the fuel flow rate delivered out of the high-pressure accumulator to an injection nozzle. The throughflow limiter is formed as a separate component which is fixed by the screw connection between a holding body and an accumulator pipe. However, there is no pressure relief feature which would release the pressure level in the injector in case of a malfunction or when the engine is unexpectedly shut down.

[0005] US 2010/0313852 A1 is related to a fuel injector comprising an injection nozzle for fuel with a valve comprising a ball-shaped valve element arranged in an injector body for the pressure relief of a control chamber. The valve with the spherically embodied valve element is prestressed by a valve spring and is pressed into a closing position.

[0006] US 2003/0111548 A1 discloses an injector for a common rail injection system for internal combustion engines having an injection nozzle that has a nozzle needle and having a control chamber subdivided into three portions by a control plunger.

[0007] WO 03/076794 A1 discloses a fuel injection system used in internal combustion engines. The injection system comprises pumping units which are used to pump fuel from a fuel tank in order to supply at least one high pressure line to the cylinders of the internal combustion engine. The at least one high pressure line is used to supply a plurality of fuel injectors respectively provided with an injector nozzle which respectively provides a combustion chamber of the internal combustion engine with fuel. The at least one high pressure line comprises line sections connecting the individual fuel injectors to each other. The bodies of the fuel injectors comprise an integrated storage chamber.

[0008] An object of the invention is to provide a fuel injection valve arrangement in which the performance is considerably improved compared to the prior art solutions.

Disclosure of the Invention

[0009] Object of the invention is substantially met by a fuel injection valve arrangement comprising a fuel injector body, a nozzle needle arranged longitudinally movably in a first end of the fuel injector body and surrounded at least partially by a needle chamber, the fuel injection valve arrangement further comprises a flow fuse valve unit having an inlet in flow communication with a high-pressure accumulator and an outlet in flow communication with the needle chamber, and the flow fuse valve unit is arranged to allow predetermined amount of fuel to flow in a direction from the inlet of the flow fuse valve unit to the outlet of the flow fuse valve unit. It is characteristic to the invention that at least one one-way valve element is integrated to a piston unit of the flow fuse valve unit and arranged to allow fuel to flow in a direction from the outlet of the flow fuse valve unit to the inlet of the flow fuse valve unit in response to a pressure difference between the outlet and the inlet of the flow fuse valve unit.

[0010] This provides a fuel injection valve arrangement which performance is considerably improved. The fuel injection valve arrangement is long-lasting, reliable and safe with reduced amount of complex structures. The one-way valve element integrated with the flow fuse valve unit may be arranged in flow communication with the high-pressure accumulator so as to reduce an amount of residual fuel in case of failure operations or shut downs. In normal injection operations, the one-way valve element stays closed and thus the fuel flow in the direction from the nozzle chamber to the high-pressure accumulator is prevented. The one-way valve element may open in the event when the engine is shut down and the pressure in the high-pressure accumulator drops down in a controlled manner or in an unexpected shut down wherein the pressure in the high-pressure accumulator suddenly drops. More advantageously, due to the fact that high pressure from the nozzle chamber is released by the one-way valve element, the fuel injection valve arrangement is very safe. The flow fuse valve unit may be located substantially close to the nozzle chamber which allows minimal amounts of residual fuel in case of failure operation or in unexpected shut down.

[0011] According to an embodiment of the invention, the fuel injection arrangement comprises only one one-way valve element that is integrated to the piston unit of the flow fuse valve unit.

[0012] According to an embodiment of the invention, the flow fuse valve unit is arranged in the injector body. This makes the fuel injection valve arrangement to be compact.

[0013] According to a preferably embodiment of the invention the high-pressure accumulator is integrated in a second end of the fuel injector body. In this case, also the flow fuse valve unit is arranged in the injector body and is arranged operationally and physically between the high-pressure accumulator and the nozzle needle located at the first end of the injector body. This provides a very compact structure for the injector body.

[0014] According to an embodiment of the invention, the one-way valve element comprises a ball-shaped valve element, and a spring element so as urge the one-way valve element to a closing position and allowing to open the one-way valve element in response to the pressure difference between the outlet and the inlet of the flow fuse valve unit. The ball-shaped valve element may be arranged at a first end of the one-way valve element and at a repose position the ball-shaped valve element rests at a valve seat. When the one-way valve element opens, the ball-shaped valve element moves away from the valve seat so as to open the flow communication in the direction from the outlet of the flow fuse valve unit to the inlet of the flow fuse valve unit in response to a pressure difference between the outlet and the inlet of the flow fuse valve unit.

[0015] According to an embodiment of the invention, the flow fuse valve unit comprises a spring element that forces the flow fuse valve unit towards a closing position wherein the flow communication in the direction from the inlet of the flow fuse valve unit to the outlet of the flow fuse valve unit is closed.

[0016] According to an embodiment of the invention, a spring constant of the spring element of the flow fuse valve unit differs from a spring constant of the spring element of the one-way valve element.

[0017] According to an embodiment of the invention, the flow fuse valve unit is enclosed by a replaceable housing having a ceiling where the spring element urges the flow fuse valve unit towards to.

[0018] According to an embodiment of the invention, the flow fuse valve unit is prevented from a direct contact with inner surfaces of the fuel injector body by the housing.

[0019] According to an embodiment of the invention, a collar surface is integrated in the fuel injector body towards to the spring element of the flow fuse valve unit urges the flow fuse valve unit.

[0020] According to an embodiment of the invention, a size of the one-way valve element is smaller than a size of the flow fuse valve unit.

[0021] According to an embodiment of the invention, the high-pressure accumulator, the flow fuse valve unit and the nozzle needle are arranged nonaligned to each other with respect to a longitudinal central axis of the nozzle needle.

Brief Description of Drawings

[0022] In the following, the invention will be described with reference to the accompanying exemplary, schematic drawings, in which

Figure 1 illustrates a fuel injection valve arrangement for an internal combustion piston engine according to the first embodiment of the invention,

Figure 2 illustrates an injection moment of the fuel injection valve arrangement for an internal combustion piston engine according to the second embodiment of the invention,

Figure 3, illustrates a fuel injection valve arrangement for an internal combustion piston engine when a one-way valve element is in its opening position according to the third embodiment of the invention,

Figure 4, illustrates a fuel injection valve arrangement for an internal combustion piston engine according to the fourth embodiment of the invention,

Figure 5, illustrates a fuel injection valve arrangement for an internal combustion piston engine according to the fifth embodiment of the invention, and

Figure 6, illustrates a fuel injection valve arrangement for an internal combustion piston engine according to the sixth embodiment of the invention.

Detailed Description of Drawings

[0023] Figure 1 depicts schematically a fuel injection valve arrangement 10 according to an embodiment of the invention. Firstly the fuel injection valve arrangement comprises a fuel injector body 12. The fuel injector body 12 in this embodiment is substantially formed of two parts fastened together: a first part 12.1 arranged at a first end of the injector body 12 and a second part 12.2 arranged at a second end of the injector body 12. The fuel injector body 12 comprises a nozzle needle 14 arranged longitudinally movably in the first end of the fuel injector body 12. The nozzle needle is surrounded at least partially by a needle chamber 16. The needle chamber 16 may be arranged to be in flow communication through openings 15 to a combustion chamber of the engine, which openings are opened and closed by means of the nozzle needle 14. In this embodiment of the invention, in the second end of the fuel injector body 12, opposite to the first end of the fuel injector body 12, is arranged a high-pressure accumulator 30. Thus, the high-pressure accumulator 30 is integrated in the fuel injector body 12. The high-pressure accumulator 30 is in flow communication with a fuel source via a fuel conduit 80.

[0024] The fuel injection valve arrangement 10 comprises a flow fuse valve unit 20 having an inlet 22 in flow communication with the high-pressure accumulator 30 and an outlet 24 in flow communication with the needle chamber 16. The flow fuse valve unit 20 is operationally and physically arranged between the high-pressure accumulator 30 and the nozzle needle 14 in the fuel injector body 12. Furthermore, a spring element 26 is arranged to urge the flow fuse valve unit 20 towards the inlet 22 of the flow fuse valve unit 20 and towards the high-pressure accumulator 30, which is also the direction towards the second end of the injector body.

[0025] In normal operation a valve member 71 of the flow fuse valve unit 20 moves towards the first end ruled by the volume of the injected fuel amount and the dimensions of the valve member. Between the injections the valve member 71 is returned back to its initial position by the spring element 26 allowing fuel flow bypass the valve member. In case of e.g. a malfunction of the nozzle needle 14 the valve member moves towards the first end of the injector body until it reaches a position where the valve member 71 closes the flow connection between the inlet and the outlet of the flow fuse unit 20. This way, the flow fuse valve unit 20 is arranged to allow predetermined amount of fuel to flow in a direction from the inlet 22 of the flow fuse valve unit 20 to the outlet 24 of the flow fuse valve unit 20. In other words, the flow fuse valve unit 20 is arranged to allow the predetermined amount of fuel to flow from the high-pressure accumulator 30 to the needle chamber 16. In Fig. 1, the valve member 71 is a piston or alike and thus it can be called as a piston unit.

[0026] The flow fuse valve unit 20 comprises a housing 70 which has been arranged to the injector body 12. Thus, the spring element 26 urges the flow fuse valve member 71 towards a ceiling 72 of the housing 70 located at a high-pressure accumulator 30 side. There is a gap or a groove 28 arranged between the flow fuse valve member 71 and the housing 70 so as to allow fuel to flow from the inlet 22 side of the flow fuse valve unit 20 to the outlet 24 side of the flow fuse valve unit 20 when the flow fuse valve member 20 returns back to its initial position between the injections.

[0027] In Fig. 1, the outlet 24 of the flow fuse valve unit 20 is in flow communication with the needle chamber 16 with a conduit 18. The conduit 18 has a branch 19 that comprises a valve orifice 50 with a constriction 54 leading to a control volume 17 of the injector needle 14. There is also a discharge conduit 56 provided with the valve orifice 50 which comprises a second constriction 54, the discharge conduit 56 leading from the control volume 17 a discharge conduit 56 and further to a low pressure section. In other words, the control section 17 is further in flow communication via the second constriction 52 with the discharge conduit 56 which is provided with a solenoid valve 60 having and opening position 64 and closing position 62 to the discharge outlet 66 to a low pressure system. In Fig. 1, the flow communication from the control section 17 to the discharge outlet 66 is closed that is the solenoid valve 60 is in closing position 62.

[0028] The flow fuse valve unit 20 further comprises a one-way valve element 40 integrated therein at a first end of the flow fuse valve unit 20. The one-way valve element 40 is arranged to allow fuel to flow in a direction from the outlet 24 of the flow fuse valve unit 20 to the inlet 22 of the flow fuse valve unit 20 in response to a pressure difference between the outlet 24 and the inlet 22 of the flow fuse valve unit 20. As illustrated in Fig. 1, the one-way valve element 40 comprises a spring element 42 and a valve element 44. The spring element 42 of the one-way valve element urges the ball-shaped valve element 44 towards a valve seat 46. When the one-way valve element 40 is closed, the ball-shaped valve element 44 rests on the valve seat 46. In this position, which is the normal operational position it closes a flow path via the one-way valve element 40 between an inlet 47 of the one-way valve element 40 and a channel 27 of the flow fuse valve unit 20. In a normal operation modes the one-way valve element 40 stays closed that is the ball-shaped valve element 44 rests on the valve seat 46 due to the fact that the pressure in the high-pressure accumulator 30 is substantially the same or greater than the pressure in the needle chamber 16 or volume in the outlet side of the valve member 71. However, it should be noted that the valve element 44 of the one-way valve element 40 may be of different form, other than a ball, such as a cone or a pin, depending on the application. Respective the counter surface must be designed accordingly.

[0029] When there is pressure level is higher in the outlet 24 of the flow fuse valve unit 20 side than in the inlet 22 of the flow fuse valve unit 20, the ball-shaped valve element 44 of the one-way valve 40 moves away from the valve seat 46 and opens the flow path via the one-way valve element 40 between an inlet 47 of the one-way valve element 40 and a channel 27 of the flow fuse valve unit 20 substantially equalizing the pressure. Then at least a portion of fuel at higher pressure in the needle chamber 16 and in the control chamber 17 is allowed to flow via the one-way valve element 40 into the high-pressure accumulator 30.

[0030] The one-way valve element 40 may open in the event the pressure in the high-pressure accumulator 30 drops down in a controlled manner i.e. when the engine is shut down or in an unexpected shut down wherein the pressure in the high-pressure accumulator suddenly drops. When the one-way valve element 40 opens the flow path in a direction from the outlet 24 of the flow fuse valve unit 20 to the inlet 22 of the flow fuse valve unit 20 and releases the pressure from the nozzle chamber 16. Advantageously, this is a significant safety factor due to the fact that the high pressure from the nozzle chamber 16 is released. Furthermore, the flow fuse valve unit 20 is located substantially close to the nozzle chamber 16 which allows minimal amounts of residual fuel in case of a failure or an unexpected shut down of the engine.

[0031] When the pressure level in the fuel injector body is stabilized, the one-way valve element 40 closes the flow communication from the outlet 24 of the flow fuse valve unit 20 to the inlet 22 of the flow fuse valve unit 20 so that the ball-shaped valve element 44 rests on the valve seat 46. This is particularly illustrated in Fig. 1 and it can be referred to a repose position since the pressure levels are stabilized. In the repose position both the flow fuse valve unit 20 and the one-way valve element 40 are closed so that fuel flow from the high-pressure accumulator 30 to the nozzle chamber 16 as well as fuel flow from the nozzle chamber 16 to the high-pressure accumulator 30 are prevented.

[0032] Figure 2 illustrates schematically a fuel injection moment. The solenoid valve 60 is in opening position 64 so as to provide the flow communication from the control chamber 17 via the discharge conduit 56 to the discharge outlet 66 into the low pressure system. Therefore, the pressure drops in the control chamber 17 and the higher pressure in the needle chamber 16 forces the nozzle needle 14 to move away from its closing position so as to open the openings 15 and an injection takes place. Since fuel flow out of the needle chamber 16 the flow fuse valve member 71 moves a respective distance from the closing position towards the outlet side 24.

[0033] Figure 3 illustrates schematically an embodiment where the one-way valve element 40 is in its opening position where the flow communication from the outlet 24 of the flow fuse valve unit 20 to the inlet 22 of the flow fuse valve unit 20 is open. As earlier described, the one-way valve element 40 may open in the event the pressure in the high-pressure accumulator 30 drops down in a controlled manner i.e. when the engine is shut down or in an unexpected shut down wherein the pressure in the high-pressure accumulator suddenly drops. In other words, there is a higher pressure in the nozzle needle 14 side or volume in the outlet side of the valve member 71 that urges the one-way valve element 40 to open the flow path via the one-way valve element 40 between an inlet 47 of the one-way valve element 40 and a channel 27 of the flow fuse valve unit 20 substantially equalizing the pressure. As illustrated in Fig. 3, the higher pressure in the nozzle needle 14 side or volume in the outlet side of the valve member 71 compresses the spring element 42 of the one-way valve element 40 and urges the ball-shaped valve element 44 away from its valve seat 46.

[0034] Figure 4 illustrates schematically an embodiment wherein one or more of the flow fuse valve unit 20 and the high-pressure accumulator 30 are separated from the injector body 12. In addition, the high-pressure accumulator 30 may be separated from the flow fuse valve unit 20. Furthermore, the high-pressure accumulator 30, the flow fuse valve unit 20 and the nozzle needle 14 may be arranged nonaligned with respect to each other which means that they do not share a common longitudinal central axis. However, the operation principle in the fuel injection valve unit 10 shown in Fig. 3 is the same as in Figures 1 and 2. The one-way valve 40 is illustrated in Fig. 4 as a general symbol due to the fact that the one-way valve element 40 may be of different form and construction, other than a ball, such as a cone or a pin, depending on the application. Respective the counter surface must be designed accordingly..

[0035] Figure 5 illustrates schematically another embodiment of the flow fuse valve unit 20. Compared to the embodiment of Figures 1 and 2, the embodiment of Figure 4 does not include a replaceable housing element as in Figures 1-4 but the flow fuse member 20 is integrated directly to the accumulator in fuel injector body 12. The spring element 26 of the flow fuse valve member 20 forces the flow fuse valve member towards a collar surface 13 that arranged to the inner surface of the accumulator operating as a sealing surface for the flow fuse member 20. So the flow fuse valve member is integrated in the fuel injector body 12. In addition, the flow fuse valve member 20 is in contact with the inner walls of the accumulator or fuel injector body 12. However, there need to be the gap or a groove 28 so as to provide the flow path for fuel to travel from the inlet 22 of the flow fuse valve unit 20 to the outlet 24 of the flow fuse valve unit 20 for returning the flow fuse valve member back to its initial position. Fig. 5 illustrates schematically as an example, that the one-way valve element 40 comprises a cone-like valve element 44.

[0036] Figure 6 illustrates schematically, that two one-way valve elements 40' and 40" are integrated into the flow fuse valve unit 30. The one-way valve elements comprise the same features as the one-way valve element 40 shown in Figures 1-5 and are indicated in Figure 6 using ' and " indices after the reference number such as 40' and 40". In some applications it may be advantageous to have one or more one-way valve units with the flow fuse valve unit 20. In case, the one-way valve units 40' and 40" comprises each spring element 42' and 42", each of the spring elements 42' and 42" may be provided with a different spring coefficients.

[0037] All the same features are indicated by using the same reference characteristics in Figures 1-6.

[0038] The fuel injection valve arrangement of the invention may be used in many different applications, for example in dual-fuel engines which are sometimes called as gas engines due to the fact that their main fuel is normally natural gas. The gas engines require the pilot fuel such as diesel fuel to ignite the gas. However, the fuel injection valve arrangement may also be applied in single fuel engines.

[0039] While the invention has been described herein by way of examples in connection with what are, at present, considered to be the most preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but is intended to cover various combinations or modifications of its features, and several other applications included within the scope of the invention, as defined in the appended claims. The details mentioned in connection with any embodiment above may be used in connection with another embodiment when such combination is technically feasible and as long as this combination falls within the scope defined by the appended claims.

Claims

1. A fuel injection valve arrangement (10) for internal combustion engine, comprising a fuel injector body (12), a nozzle needle (14) arranged longitudinally movably in a first end of the fuel injector body (12) and surrounded at least partially by a needle chamber (16), the fuel injection valve arrangement (10) further comprises a flow fuse valve unit (20) having an inlet (22) in flow communication with a high-pressure accumulator (30) and an outlet (24) in flow communication with the needle chamber (16), and the flow fuse valve unit (20) is arranged to allow predetermined amount of fuel to flow in a direction from the inlet (22) of the flow fuse valve unit (20) to the outlet (24) of the flow fuse valve unit (20), characterized in that at least one one-way valve element (40) is integrated to a piston unit (71) of the flow fuse valve unit (20) and arranged to allow fuel to flow in a direction from the needle chamber (16) to the high-pressure accumulator (30) in response to a pressure difference between the outlet (24) and the inlet (22) of the flow fuse valve unit (20).

2. A fuel injection valve arrangement (10) according to claim 1, characterized in that the fuel injection arrangement comprises only one one-way valve unit (20) that is integrated to the piston unit (71) of the flow fuse valve unit (20).

3. A fuel injection valve arrangement (10) according to anyone of preceding claims 1 or 2, characterized in that the flow fuse valve unit (40) is arranged in the injector body (12).

4. A fuel injection valve arrangement (10) according to anyone of preceding claims 1-3, characterized in that the high pressure accumulator (30) is integrated in a second end of the fuel injector body (12).

5. A fuel injection valve arrangement (10) according to anyone of preceding claims 1-4, characterized in that the one-way valve element (40) comprises a ball-shaped valve element (44), and a spring element (42) so as urge the one-way valve element (40) to a closing position and allowing to open the one-way valve element (40) in response to the pressure difference between the outlet (24) and the inlet (22) of the flow fuse valve unit (20).

6. A fuel injection valve arrangement (10) according to anyone of preceding claims 1-5, characterized in that the flow fuse valve unit (20) comprises a spring element (26) that forces the flow fuse valve unit (20) towards a closing position wherein the flow communication in the direction from the inlet (22) of the flow fuse valve unit (20) to the outlet (24) of the flow fuse valve unit (20) is closed.

7. A fuel injection valve arrangement (10) according to claim 6, characterized in that a spring constant of the spring element (26) of the flow fuse valve unit (20) differs from a spring constant of the spring element (42) of the one-way valve element (40).

8. A fuel injection valve arrangement (10) according to anyone of preceding claims 6-7, characterized in that the flow fuse valve unit (20) is enclosed by a replaceable housing (70) having a ceiling (72) wherein the spring element (26) urges the flow fuse valve unit (20) towards to the ceiling.

9. A fuel injection valve arrangement (10) according to anyone of preceding claims 6-8, characterized in that the flow fuse valve unit (20) is prevented by the housing (70) from a direct contact with inner surfaces of the fuel injector body (12) by the housing (70).

10. A fuel injection valve arrangement (10) according to anyone of preceding claims 6-9, characterized in that a collar surface (13) is integrated in the fuel injector body (12) towards to the spring element (26) of the flow fuse valve unit (20) urges the flow fuse valve unit (20).

11. A fuel injection valve arrangement (10) according to anyone of preceding claims 1-10, characterized in that a size of the one-way valve element (40) is smaller than a size of the flow fuse valve unit (20).

12. A fuel injection valve arrangement according to anyone of preceding claims 1-11, characterized in that the high-pressure accumulator (30), the flow fuse valve unit (20) and the nozzle needle (14) are arranged nonaligned to each other with respect to a longitudinal central axis of the nozzle needle (14).

Ansprüche

1. Kraftstoff-Einspritzventilanordnung (10) für einen Verbrennungsmotor, die einen Kraftstoff-Einspritzvorrichtungskörper (12), eine Düsennadel (14), die in Längsrichtung beweglich in einem ersten Ende des Kraftstoff-Einspritzvorrichtungskörpers (12) angeordnet und wenigstens teilweise von einer Nadelkammer (16) umgeben ist, umfasst, wobei die Kraftstoff-Einspritzventilanordnung (10) ferner eine Strömungssicherungsventileinheit (20) umfasst, die einen Einlass (22) in Fluidverbindung mit einem Hochdrucksammler (30) und einen Auslass (24) in Fluidverbindung mit der Nadelkammer (16) aufweist und die Strömungssicherungsventileinheit (20) dafür angeordnet ist, zu ermöglichen, dass eine vorbestimmte Menge an Kraftstoff in einer Richtung vom Einlass (22) der Strömungssicherungsventileinheit (20) zum Auslass (24) der Strömungssicherungsventileinheit (20) strömt, dadurch gekennzeichnet, dass wenigstens ein Einweg-Ventilelement (40) mit einer Kolbeneinheit (71) der Strömungssicherungsventileinheit (20) integriert und dafür angeordnet ist, zu ermöglichen, dass als Reaktion auf eine Druckdifferenz zwischen dem Auslass (24) und dem Einlass (22) der Strömungssicherungsventileinheit (20) Kraftstoff in einer Richtung von der Nadelkammer (16) zum Hochdrucksammler (30) strömt.

2. Kraftstoff-Einspritzventilanordnung (10) nach Anspruch 1, dadurch gekennzeichnet, dass die Kraftstoff-Einspritzventilanordnung nur eine Einweg-Ventileinheit (20) umfasst, die mit der Kolbeneinheit (71) der Strömungssicherungsventileinheit (20) integriert ist.

3. Kraftstoff-Einspritzventilanordnung (10) nach einem der vorhergehenden Ansprüche 1 oder 2, dadurch gekennzeichnet, dass die Strömungssicherungsventileinheit (40) im Einspritzvorrichtungskörper (12) integriert ist.

4. Kraftstoff-Einspritzventilanordnung (10) nach einem der vorhergehenden Ansprüche 1 bis 3, dadurch gekennzeichnet, dass der Hochdrucksammler (30) in einem zweiten Ende des Einspritzvorrichtungskörpers (12) integriert ist.

5. Kraftstoff-Einspritzventilanordnung (10) nach einem der vorhergehenden Ansprüche 1 bis 4, dadurch gekennzeichnet, dass das Einweg-Ventilelement (40) ein kugelförmiges Ventilelement (44) und ein Federelement (42) umfasst, um so das Einweg-Ventilelement (40) zu einer Schließstellung zu drängen und zu ermöglichen, dass das Einweg-Ventilelement (40) als Reaktion auf die Druckdifferenz zwischen dem Auslass (24) und dem Einlass (22) der Strömungssicherungsventileinheit (20) öffnet.

6. Kraftstoff-Einspritzventilanordnung (10) nach einem der vorhergehenden Ansprüche 1 bis 5, dadurch gekennzeichnet, dass die Strömungssicherungsventileinheit (20) ein Federelement (26) umfasst, das die Strömungssicherungsventileinheit (20) zu einer Schließstellung hin zwingt, wobei die Strömungsverbindung in der Richtung vom Einlass (22) der Strömungssicherungsventileinheit (20) zum Auslass (24) der Strömungssicherungsventileinheit (20) geschlossen ist.

7. Kraftstoff-Einspritzventilanordnung (10) nach Anspruch 6, dadurch gekennzeichnet, dass sich eine Federkonstante des Federelements (26) der Strömungssicherungsventileinheit (20) von einer Federkonstante des Federelements (42) des Einweg-Ventilelements (40) unterscheidet.

8. Kraftstoff-Einspritzventilanordnung (10) nach einem der vorhergehenden Ansprüche 6 bis 7, dadurch gekennzeichnet, dass die Strömungssicherungsventileinheit (20) durch ein austauschbares Gehäuse (70) umschlossen wird, das eine Decke (72) aufweist, wobei das Federelement (26) die Strömungssicherungsventileinheit (20) zur Decke hin drängt.

9. Kraftstoff-Einspritzventilanordnung (10) nach einem der vorhergehenden Ansprüche 6 bis 8, dadurch gekennzeichnet, dass die Strömungssicherungsventileinheit (20) durch das Gehäuse (70) an einer unmittelbaren Berührung mit Innenflächen des Kraftstoff-Einspritzvorrichtungskörpers (12) durch das Gehäuse (70) gehindert wird.

10. Kraftstoff-Einspritzventilanordnung (10) nach einem der vorhergehenden Ansprüche 6 bis 9, dadurch gekennzeichnet, dass eine Bundfläche (13), die im Einspritzvorrichtungskörper (12) zum Federelement (26) der Strömungssicherungsventileinheit (20) hin integriert ist, die Strömungssicherungsventileinheit (20) drängt.

11. Kraftstoff-Einspritzventilanordnung (10) nach einem der vorhergehenden Ansprüche 1 bis 10, dadurch gekennzeichnet, dass eine Größe des Einweg-Ventilelements (40) kleiner ist als eine Größe der Strömungssicherungsventileinheit (20).

12. Kraftstoff-Einspritzventilanordnung nach einem der vorhergehenden Ansprüche 1 bis 11, dadurch gekennzeichnet, dass der Hochdrucksammler (30), die Strömungssicherungsventileinheit (20) und die Düsennadel (14) nicht miteinander ausgerichtet in Bezug auf eine Längsmittelachse der Düsennadel (14) angeordnet sind.

Revendications

1. Agencement de soupape d'injection de carburant (10) pour moteur à combustion interne, comprenant un corps d'injecteur de carburant (12), une aiguille d'injecteur (14) disposée longitudinalement mobile dans une première extrémité du corps d'injecteur de carburant (12) et entourée au moins en partie par une chambre d'aiguille (16), l'agencement de soupape d'injection de carburant (10) comprenant en plus une unité de soupape à fusible d'écoulement (20) ayant une entrée (22) en communication d'écoulement avec un accumulateur haute pression (30) et une sortie (24) en communication d'écoulement avec la chambre d'aiguille (16) et l'unité de soupape à fusible d'écoulement (20) étant agencée pour permettre à une quantité prédéterminée de carburant de s'écouler dans une direction allant de l'entrée (22) de l'unité de soupape à fusible d'écoulement (20) et une sortie (24) de l'unité de soupape à fusible d'écoulement (20), caractérisé en ce qu'au moins un élément de soupape à une voie (40) est intégré à une unité de piston (71) de l'unité de soupape à fusible d'écoulement (20) et disposé pour permettre au carburant de s'écouler dans une direction allant de la chambre d'aiguille (16) à l'accumulateur haute pression (30) en réaction à une différence de pression entre la sortie (24) et l'entrée (22) de l'unité de soupape à fusible d'écoulement (20).

2. Agencement de soupape d'injection de carburant (10) selon la revendication 1, caractérisé en ce que l'agencement d'injection de carburant comprend seulement une soupape à une voie (20) qui est intégrée à une unité de piston (71) de l'unité de soupape à fusible d'écoulement (20).

3. Agencement de soupape d'injection de carburant (10) selon l'une quelconque des revendications 1 ou 2, caractérisé en ce que l'unité de soupape à fusible d'écoulement (40) est disposée dans le corps d'injecteur (12) .

4. Agencement de soupape d'injection de carburant (10) selon l'une quelconque des revendications précédentes 1-3, caractérisé en ce que l'accumulateur haute pression (30) est intégré dans une deuxième extrémité du corps d'injecteur de carburant (12).

5. Agencement de soupape d'injection de carburant (10) selon l'une quelconque des revendications précédentes 1-4, caractérisé en ce que l'élément de soupape à une voie (40) comprend un élément de soupape de forme sphérique (44) et un élément à ressort (42) de sorte à pousser l'élément de soupape à une voie (40) vers une position de fermeture et permettre l'ouverture de l'élément de soupape à une voie (40) en réaction à la différence de pression entre la sortie (24) et l'entrée (22) de l'unité de soupape à fusible d'écoulement (20).

6. Agencement de soupape d'injection de carburant (10) selon l'une quelconque des revendications précédentes 1-5, caractérisé en ce que l'unité de soupape à fusible d'écoulement (20) comprend un élément à ressort (26) qui force l'unité de soupape à fusible d'écoulement (20) vers une position de fermeture dans laquelle la communication en écoulement dans la direction venant de l'entrée (22) de l'unité de soupape à fusible d'écoulement (20) vers la sortie (24) de l'unité de soupape à fusible d'écoulement (20) est fermée.

7. Agencement de soupape d'injection de carburant (10) selon la revendication 6, caractérisé en ce qu'une constante de ressort de l'élément à ressort (26) de l'unité de soupape à fusible d'écoulement (20) diffère d'une constante de ressort de l'élément à ressort (42) de l'élément de soupape à une voie (40).

8. Agencement de soupape d'injection de carburant (10) selon l'une quelconque des revendications précédentes 6-7, caractérisé en ce que l'unité de soupape à fusible d'écoulement (20) est enfermée par un boîtier remplaçable (70) ayant un plafond (72) dans lequel l'élément à ressort (26) pousse l'unité de soupape à fusible d'écoulement (20) vers le plafond.

9. Agencement de soupape d'injection de carburant (10) selon l'une quelconque des revendications précédentes 6-8, caractérisé en ce que l'unité de soupape à fusible d'écoulement (20) est protégée par le boîtier (70) d'un contact direct avec les surfaces intérieures du corps d'injecteur de carburant (12) par le boîtier (70) .

10. Agencement de soupape d'injection de carburant (10) selon l'une quelconque des revendications précédentes 6-9, caractérisé en ce qu'une surface de collet (13) est intégrée dans le corps d'injecteur de carburant (12) vers l'élément à ressort (26) de l'unité de soupape à fusible d'écoulement (20) et pousse l'unité de soupape à fusible d'écoulement (20).

11. Agencement de soupape d'injection de carburant (10) selon l'une quelconque des revendications précédentes 1-10, caractérisé en ce qu'une taille de l'élément de soupape à une voie (40) est plus petite qu'une taille de l'unité de soupape à fusible d'écoulement (20).

12. Agencement de soupape d'injection de carburant l'une quelconque des revendications précédentes 1-11, caractérisé en ce que l'accumulateur haute pression (30), l'unité de soupape à fusible d'écoulement (20) et l'aiguille d'injecteur (14) sont disposés non alignés l'un par rapport à l'autre eu égard à l'axe central longitudinal de l'aiguille d'injecteur (14).

Drawing