AT520481B1 - Injection system for a fuel cell system for injecting fuel into a combustion chamber - Google Patents

Abstract

The invention relates to an injection system (1) for a fuel cell system (2), comprising an injector (3) for injecting fuel (4) into a combustion chamber (5) of the fuel cell system (2), and a fuel metering chamber (6) for metering Intermediate storage of the fuel (4) for the injector (3), and an injection valve (7) for the metered injection of the fuel (4) into the fuel metering chamber (6), the fuel metering chamber (6) in a positioning body (8) , For positioning the injector (3) and the injection valve (7) in the fuel cell system (2), is designed, wherein from the fuel metering chamber (6) within the positioning body (8) a fluid pressure determination channel (14) towards an outside of the Positioning body (8) branches to determine a fluid pressure in the fuel metering chamber (6). The invention further relates to a fuel cell system (2) with the injection system (1), a motor vehicle (18) with the fuel cell system (2) and a method for injecting fuel into the combustion chamber (5) using the injection system (1) according to the invention.

Description

description

INJECTION SYSTEM FOR A FUEL CELL SYSTEM FOR INJECTING FUEL INTO A COMBUSTION COMPOSITION The present invention relates to an injection system for a fuel cell system, comprising an injector for injecting fuel into a combustion chamber of the fuel cell system, a fuel metering chamber for metered intermediate storage of the fuel for the injector for the injector. and an injection valve for metered injection of the fuel into the fuel metering chamber. The invention further relates to a fuel cell system and a motor vehicle with a fuel cell system.

Various injection systems are known in the prior art. Injection systems are generally used to inject fuel or a fuel mixture into a combustion chamber of a combustion chamber. An injector, for example in the form of a single fluid nozzle, can be used to inject the fuel, since the fuel can be injected into the combustion chamber with a high degree of atomization via such an injector. In addition, a single fluid nozzle is relatively inexpensive. Until now, however, the use of a single fluid nozzle has required a complex pressure regulation system in order to be able to reliably supply a defined amount of fuel to the single fluid nozzle. Single fluid nozzles are therefore not necessarily the preferred choice.

DE 198 44 163 C1 discloses a method for metering, pulse-like pumping of fluid media under high pressure, wherein a pressure surge resulting from the stored kinetic energy of an electromagnetically driven armature element of a reciprocating piston pump via a blocking body in a with a spray-off device useful fluid enclosed in the pressure chamber is transmitted, so that a predetermined amount of the useful fluid is conveyed out of an injection unit, the stored kinetic energy of the anchor element being abruptly transmitted to a working fluid enclosed in the pressure antechamber upstream of the pressure chamber inducing a pressure surge which occurs in the Spreading working fluid is transferred to the locking body and from the locking body to the useful fluid. Such a device for supplying the fluid media to the spraying device requires a relatively complex system structure.

Injection systems for liquid or gaseous fuels for injecting a fluid into an exhaust line of an internal combustion engine are known, for example, from WO 2013117311 A1, EP 2427650 A1, EP 2522846 A2, DE 102010039046 A1 and EP 1431564 A2. These each have an injector, a metering chamber and an injection valve.

The object of the present invention is to at least partially take into account the problems described above. In particular, it is an object of the present invention to provide an injection system, a fuel cell system, a motor vehicle and a method with which or in which fuel it is possible to inject fuel into a combustion chamber in a simple, reliable and cost-effective manner.

The above object is solved by the claims. In particular, the above object is achieved by the injection system according to claim 1, the fuel cell system according to claim 11, the motor vehicle according to claim 12 and the method according to claim 13. Further advantages of the invention result from the subclaims, the description and the drawings. Features and details that are described in connection with the injection system apply, of course, also in connection with the fuel cell system according to the invention, the motor vehicle according to the invention, the method according to the invention and vice versa, so that with respect to the disclosure of the individual aspects of the invention, reference is always made to one another or can be.

According to a first aspect of the present invention, an injection system for

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AT 520 481 B1 2020-03-15 Austrian patent office provided a fuel cell system. The injection system has an injector for injecting fuel into a combustion chamber of the fuel cell system, a fuel metering chamber for metered intermediate storage of the fuel for the injector, and an injection valve for metered injection of the fuel into the fuel metering chamber. The fuel metering chamber is configured in a positioning body for positioning the injector and the injection valve in the fuel cell system.

Using the positioning body according to the invention, the injection valve and the injector can be easily positioned in the fuel cell system, in particular relative to one another and / or relative to the combustion chamber. In an arrangement according to the invention, fuel or a fuel mixture can first be injected through the injection valve into the fuel metering chamber in the positioning body. As a result, the desired or a defined amount of fuel can initially be made available to the injector. As soon as the fuel is in the fuel metering chamber, it can be injected into the combustion chamber through the injector. This eliminates the need for a complex feed and / or metering mechanism to provide the desired amount of fuel to the injector. The present injection system can thus be provided at a correspondingly low cost.

In an injection system according to the invention, it is also particularly simple to replace a faulty injection valve and / or a faulty injector.

By injecting the fuel directly into the fuel metering chamber, it is also possible in a simple manner to provide the desired fuel pressure at the injector. All that is required for this is a correspondingly defined injection process through the injection nozzle.

[0011] In the present case, the fuel cell system is to be understood in particular as an SOFC system. The injection system is accordingly designed for injecting a fuel into a combustion chamber of an SOFC system. The respective functional components of the injection system are designed to be sufficiently heat-resistant. The construction according to the invention also enables, for example, a heat-sensitive injector to be positioned in a cooler or less hot or warm area.

[0012] The fuel metering chamber is preferably to be understood as an at least substantially closed chamber within the positioning body. The fuel metering chamber can be understood as an intermediate storage or as an intermediate storage chamber. The positioning body can be understood as a holding body, bearing body or fastening body for holding, storing or fastening the injection valve and the injector within the fuel cell system. That is, without the positioning body, neither the injection valve nor the injector could be positioned at the desired position in the fuel cell system in the manner according to the invention.

[0013] The combustion chamber is to be understood as a volume within a combustion chamber in which the fuel is burned or can be burned. The combustion chamber is accordingly designed as part of the positioning body.

According to a development of the present invention, it is possible that in an injection system the injection valve is attached to a first positioning section of the positioning body and the injector is attached to a second positioning section of the positioning body. As a result, the injection valve and the injector can be easily positioned, stored or fixed in a desired position in the fuel cell system. In particular, the injection body and the injector can thereby be easily positioned relative to one another. For example, the injector can first be attached to the second positioning section, the positioning body can then be arranged in the fuel cell system in the desired position, and then the injection valve can be attached to the first positioning section. Due to the positioning body designed according to the invention, the injection valve and the injector can also be particularly simple

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AT 520 481 B1 2020-03-15 Austrian patent office and stably positioned relative to the combustion chamber.

Furthermore, it is possible that in an injection system according to the present invention, the injection valve, the fuel metering chamber and the injector are at least partially aligned with one another. In particular, an injection direction of the injection valve and an injection direction of the injector preferably run in the same direction. The injection direction of the injection valve and the injection direction of the injector are particularly preferably aligned coaxially to one another. The fuel metering chamber is configured, at least in sections, in alignment between the injection direction and the injection direction. As a result, the injection system can be made available in a particularly compact and space-saving manner. In addition, dynamic forces in the injection system and thus also in the fuel cell system can be kept low. That is, the injection system can be provided with a high dynamic stability.

Furthermore, it is possible with an injection system according to the invention that the combustion chamber is located at least in sections in a housing section of the fuel cell system and the positioning body has at least one fastening section for fastening the positioning body to the housing section and thereby to form a combustion chamber in which the combustion chamber is located, having. Due to the fastening section and the corresponding configuration of the positioning body, the injection nozzle and the injector can be positioned in a particularly simple manner on and in the combustion chamber in a stable manner. As a result, the fuel can be correspondingly reliably injected into the combustion chamber. In addition, because the positioning body preferably forms part of the combustion chamber, the associated overall system can be provided in a particularly compact, material-saving and, accordingly, correspondingly weight-saving manner. This is particularly advantageous for use in mobile use.

In addition, it is possible in an injection system according to the present invention that the at least one fastening section has at least one through opening for the passage of a fastening means. As a result, the positioning body can be easily attached to the housing section. The positioning body preferably has at least two through openings, through which the positioning body can be fastened to the housing section by means of screw bodies. This fastening option can be made available at particularly low cost.

In addition, it is possible that in an injection system according to the invention the positioning body is configured in one piece or essentially in one piece. As a result, the injection system can be made available in a particularly stable, cost-effective manner and with a low degree of complexity. The one-piece, in particular monolithic structure of the positioning body can also promote a robust and correspondingly safe mode of operation of the injection system.

According to a further embodiment of the present invention, it is possible that the positioning body has a larger mass, in particular a mass more than twice as large, than the injector and / or the injection valve. This ensures that the injection valve and the injector sit securely and stably in the positioning body when the fuel cell system is in operation. This also ensures a correspondingly reliable mode of operation of the fuel cell system. With such a massive construction of the positioning body, it can, as already mentioned above, be designed as a closure body for at least partially enclosing or covering the combustion chamber. Accordingly, a separate closure or. Cover element for closing or covering the combustion chamber can be dispensed with. The degree of complexity can thus be kept correspondingly low. The mass of the positioning body is preferably greater than the mass of the injector and the injection valve combined.

In an injection system according to the invention it is further provided that

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AT 520 481 B1 2020-03-15 Austrian patent office of the fuel metering chamber branches off a fluid pressure determination channel inside the positioning body in the direction of an outside of the positioning body for determining a fluid pressure in the fuel metering chamber. This is possible in particular because of the massive construction of the positioning body proposed according to the invention. The fluid pressure in the fuel metering chamber can be determined or determined particularly easily using the fluid pressure determination channel. In conventional injection systems, this was not possible because a corresponding positioning section was either not designed in one piece or could not be designed in one piece, or simply because there was insufficient space for the fluid pressure determination channel according to the invention. The fluid pressure determination channel preferably extends from the fuel metering chamber to the outside of the positioning body, a pressure measuring device for determining or measuring the fluid pressure in the fuel metering chamber being arranged outside the positioning body. Thus, the fluid pressure or fuel pressure within the fuel metering chamber can be determined in a simple manner via the pressure measuring device outside the positioning body.

In an injection system according to the invention, it is also possible for the injector to have an individual fluid nozzle or to be designed as an individual fluid nozzle. To be more precise, the injector preferably has a single fluid atomization nozzle which can inject the fuel into the combustion chamber in a particularly finely atomized manner. Such an individual fluid nozzle can be provided inexpensively and in a space-saving manner. For the aforementioned reasons, it is only possible or sensible to use a correspondingly simply constructed individual fluid nozzle because of the structure according to the invention with regard to the preliminary storage of the fuel metering chamber and the injection valve upstream of the individual fluid nozzle.

[0022] In addition, it can be advantageous if, in the case of an injection system according to the invention, the positioning body has a conical and / or tapered end section. As already mentioned above, the positioning body can serve as a closure body or cover of a combustion chamber. With the conical and / or tapered end section, the positioning body can be placed particularly easily and securely in an opening of the combustion chamber in order to close it. Additionally or alternatively, the end section can also have a threaded section through which the positioning body can be screwed into a complementarily configured opening in the combustion chamber. This also makes it possible to provide a simple and secure closing mechanism for closing the combustion chamber by means of the positioning body.

[0023] According to a further aspect of the present invention, a fuel cell system with an injection system as described in detail above is provided. The fuel cell system has a combustion chamber in which the combustion chamber is located, the positioning body at least partially forming an inner wall section of the combustion chamber. A fuel cell system according to the invention thus brings with it the same advantages as have been described in detail with reference to the injection system according to the invention. The fuel cell system is preferably designed as an SOFC system. The injection system in the fuel cell system is preferably designed as an injection system for injecting fuel into a combustion chamber or a combustion chamber of a starting burner and / or an exhaust gas burner of the fuel cell system.

In the combustion chamber, a heating means is preferably arranged, which is designed in particular as an electrical heating means, for example as a resistance heating means. As a result of the arrangement according to the invention, the fuel can subsequently be sprayed directly onto the heating medium through the injection valve and thereby heated, evaporated and ignited particularly efficiently.

In a further aspect of the present invention, a motor vehicle having a fuel cell system as described above for providing electrical energy and at least one electric motor for driving the motor vehicle using at least partial use of the electrical energy provided by the fuel cell system

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AT 520 481 B1 2020-03-15 Austrian patent office. The motor vehicle is preferably to be understood as a car or a truck.

In addition, a method for injecting fuel into a combustion chamber of a fuel cell system is provided within the scope of the present invention with an injection system as described in detail above. The process has the following steps:

- injecting a predefined amount of fuel into the fuel metering chamber through the injection valve, and [0028] - injecting the predefined amount of fuel from the fuel metering chamber into the combustion chamber through the injector.

As a result of this injection sequence in the injection system according to the invention, the fuel, as already described above, can be dosed correctly and finely atomized into the combustion chamber using a cost-effective injector in a safe and simple manner. In addition, the method according to the invention thus has the same advantages as have been described above with reference to the injection system. The injection of a predefined amount can be understood as a metered injection of the fuel into the fuel metering chamber. A heating means can be provided in the combustion chamber, onto which the predefined amount of fuel is in particular sprayed directly.

Further measures improving the invention result from the following description of various exemplary embodiments of the invention, which are shown schematically in the figures.

[0031] Each shows schematically:

Figure 1 is a partially sectioned side view for explaining an injection system according to an embodiment of the present invention, and Figure 2 shows a motor vehicle with a fuel cell system and the injection system shown in Fig. 1 according to the present invention.

Elements with the same function and mode of operation are each provided with the same reference numerals in FIGS. 1 and 2.

In Fig. 1, an injection system 1 according to the invention for a fuel cell system 2 is shown schematically. The injection system 1 has an injector 3 for injecting fuel 4 into a combustion chamber 5 of the fuel cell system 2. The injection system 1 also has a fuel metering chamber 6 for the metered temporary storage of the fuel 4 for the injector 3. In addition, the injection system has an injection valve 7 for the metered injection of the fuel 4 into the fuel metering chamber 6. The fuel metering chamber 6 is configured in a positioning body 8 which can be arranged in the fuel cell system 2 for positioning the injector 3 and the injection valve 7. That is, the injection valve 7 and the injector 3 can be positioned or fastened to a positioning body 8 positioned in the fuel cell system 2, so that these components could in principle only be held in their position in the fuel cell system 2 by the positioning body 8.

As shown in FIG. 1, the injection valve 7 is attached to a first positioning section 16 of the positioning body 8 and the injector 3 is attached to a second positioning section 17 of the positioning body 8.

The injection valve 7, the fuel metering chamber 6 and the injector 3 are arranged in sections in alignment with one another. The injection valve 7 and the injector 3 thus have the same injection direction. The combustion chamber 5 is essentially located in a housing section 11 of the fuel cell system 2 and the positioning body 8 has two fastening sections 9, 10 for fastening the positioning body 8 to the housing

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AT 520 481 B1 2020-03-15 Austrian patent office section 11 and thereby to form a combustion chamber 13 in which the combustion chamber 5 is located.

[0038] The two fastening sections 9, 10 each have a through opening for the passage of a fastening means. The positioning body 8 can be screwed to the housing section 11 in this way.

The injector 3 also has a cover 12 which extends into the fuel metering chamber 6 or is arranged within the latter. The cover 12 is designed in particular as a wire mesh, which protects the injector 3 from dirt or foreign bodies.

[0040] The positioning body 8 is designed in one piece. In addition, the positioning body 8 has a larger mass than the injector 3 and / or the injection valve 7. The positioning body 8 is also designed as a closure body in the form of a cover for at least partially enclosing or closing the combustion chamber 5. The positioning body 8 thus forms at least part of an inner wall section 15 of the combustion chamber 5.

As further shown in FIG. 1, a fluid pressure determination channel 14 branches off from the fuel metering chamber 6 within the positioning body 8 in the direction of an outside of the positioning body 8 for determining a fluid pressure in the fuel metering chamber 6. The fluid pressure can be determined using the fluid pressure determination channel 14 with a pressure measuring device 21.

The injector 3 is designed as a single fluid nozzle. The positioning body 8 has a conical end section 20 which tapers in the direction of the combustion chamber 5.

2 shows a motor vehicle 18 with a fuel cell system 2 for providing electrical energy and at least one electric motor 19 for driving the motor vehicle 18 using at least partial use of the electrical energy provided by the fuel cell system 2. The fuel cell system 2 according to FIG. 2 has an injection system as described for FIG. 1 for injecting fuel 4 into a combustion chamber 5 of a starting burner and / or an exhaust gas burner of the fuel cell system 2.

With a renewed reference to FIG. 1, a method for injecting fuel 4 into a combustion chamber 5 of a fuel cell system 2 with the injection system 1 shown there is then explained. In a first step S1, a predetermined quantity of fuel 4 is first injected into the fuel metering chamber 6 through the injection valve 7. Here, the pressure in the fuel metering chamber 6 can be determined via the fluid pressure determination channel and the pressure measuring device 21 and, if necessary, can be adapted accordingly. The amount of fuel now in the fuel metering chamber 6 is injected into the combustion chamber 5 in a subsequent step S2 by the injector 3. A heating means (not shown) can also be arranged in the combustion chamber, onto which the fuel is subsequently sprayed in a further step S3 in order to heat, vaporize and / or ignite it.

In addition to the illustrated embodiments, the invention permits further design principles. That is, the invention should not be considered limited to the embodiments shown in the figures.

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AT 520 481 B1 2020-03-15 Austrian patent office

REFERENCE SIGN LIST

Injection system

Fuel cell system

Injector

fuel

Combustion chamber

Fuel dosing chamber

Injector

Positioning body

Fastening section

Fastening section

Housing section

cover

Combustion chamber

Fluid pressure determination channel

Inner wall section first positioning section second positioning section

Motor vehicle

Electric motor

Face

Pressure measuring device

Claims (13)

Claims 1. Injection system (1) for a fuel cell system (2), comprising an injector (3) for injecting fuel (4) into a combustion chamber (5) of the fuel cell system (2), a fuel metering chamber (6) for metered intermediate storage of the fuel (4) for the injector (3), and an injection valve (7) for the metered injection of the fuel (4) into the fuel metering chamber (6), the fuel metering chamber (6) in a positioning body (8) for positioning of the injector (3) and the injection valve (7) in the fuel cell system (2), characterized in that a fluid pressure determination channel (14) in the direction of an outside of the fuel dosing chamber (6) within the positioning body (8) Positioning body (8) branches to determine a fluid pressure in the fuel metering chamber (6). 2. Injection system (1) according to claim 1, characterized in that the injection valve (7) is attached to a first positioning section (16) of the positioning body (8) and the injector (3) to a second positioning section (17) of the positioning body (8 ) is attached. 3. Injection system (1) according to one of the preceding claims, characterized in that the injection valve (7), the fuel metering chamber (6) and the injector (3) are arranged at least in sections in alignment with one another. 4. Injection system (1) according to one of the preceding claims, characterized in that the combustion chamber (5) is at least in sections in a housing section (11) of the fuel cell system (2) and the positioning body (8) at least one fastening section (9, 10) for fixing the positioning body (8) to the housing section (11) and thereby for forming a combustion chamber (13) in which the combustion chamber (5) is located. 5. Injection system (1) according to claim 4, characterized in that the at least one fastening section (9, 10) has at least one through opening for carrying out a fastener. 6. Injection system (1) according to one of the preceding claims, characterized in that the positioning body (8) is designed in one piece or essentially in one piece. 7. Injection system (1) according to one of the preceding claims, characterized in that the positioning body (8) has a larger mass, in particular a mass more than twice as large as the injector (3) and / or the injection valve (7). 8. Injection system (1) according to one of the preceding claims, characterized in that the positioning body (8) is designed as a closure body for at least partially enclosing the combustion chamber (5). 9. Injection system (1) according to one of the preceding claims, characterized in that the injector (3) has a single fluid nozzle or is designed as a single fluid nozzle. 10. Injection system (1) according to one of the preceding claims, characterized in that the positioning body (8) has a conical and / or tapered end section (20). 8/10 AT 520 481 B1 2020-03-15 Austrian patent office 11. Fuel cell system (2) with an injection system (1) according to one of the preceding claims, further comprising a combustion chamber (13) in which the combustion chamber (5) is located, wherein the positioning body (8) at least partially an inner wall portion (15) of the Combustion chamber (5) forms. 12. Motor vehicle (18) with a fuel cell system (2) according to claim 11 for providing electrical energy and at least one electric motor (19) for driving the motor vehicle (18) using at least partially the electrical energy provided by the fuel cell system (2) . 13. A method for injecting fuel (4) into a combustion chamber (5) of a fuel cell system (2) with an injection system (1) according to one of claims 1 to 10, comprising the steps: - Injecting a predefined amount of fuel (4) into the fuel metering chamber (6) through the injection valve (7), and - Injecting the predefined amount of fuel (4) from the fuel metering chamber (6) into the combustion chamber (5) through the injector (3).