Injection valve for fuel, cylinder head comprising an injection valve, method for installing an injection valve in a cylinder head and use of a cylinder

Abstract

The invention relates to an injection valve (1) for fuels, in particular liquid fuels such as methanol and / or gaseous fuels such as natural gas or hydrogen, for installation in a cylindrical receptacle (7) of a cylinder head (6), the injection valve (1) comprising a body member (4) with a peripheral recess (3), after the injection valve (1) is installed, the recess, together with a cylindrical receptacle (7) of the cylinder head (6), forms an inlet path (2) for fuel, which is embodied as an annular space. The invention further relates to a cylinder head (6) having an injection valve (1) according to the invention, to a method for installing an injection valve (1) according to the invention in a cylinder head (6), and to the use of a cylindrical receptacle (7) of a cylinder head (6) as a housing of an injection valve (1).

Description

Technical Field

[0001] The invention relates to an injection valve for fuel, in particular for liquid fuels such as methanol and / or gaseous fuels such as natural gas or hydrogen. With the aid of the injection valve, the fuel can be injected into the combustion chamber of an internal combustion engine. For this purpose, the injection valve is installed in the cylinder head of the internal combustion engine.

[0002] Therefore, the present invention also relates to a cylinder head with an injection valve according to the present invention, which is placed in a cylindrical receptacle of the cylinder head. In addition, a method for installing the injection valve in the cylinder head and the use of the cylindrical receptacle of the cylinder head as a housing for the injection valve are also proposed. Background Art

[0003] In the prior art, injection valves for liquid fuels and / or gaseous fuels are described in various embodiments. Typically, the injection valve comprises a nozzle body and a nozzle needle which can be accommodated in the nozzle body in a reciprocating manner, at least one injection opening formed in the nozzle body being controllable by the reciprocating movement of the nozzle needle. The fuel reaches the at least one injection opening via an internal inlet channel which typically extends not only through the nozzle body but also through a retaining body of the injection valve which is axially placed on the nozzle body and is connected to the nozzle body via a nozzle clamping nut. In addition to the nozzle body and the retaining body, the injection valve can also have further body components which are clamped to one another by means of a nozzle clamping nut.

[0004] For the injection of alternative fuels, in particular liquid fuels such as methanol and / or gaseous fuels such as natural gas or hydrogen, large inlet cross sections are required due to the generally low inlet pressure and / or low energy density of the fuels, since otherwise the required fuel flow cannot be achieved. Large inlet cross sections generally require larger outer diameters, which has a negative impact on the installation space requirement of the injection valve. Summary of the invention

[0005] The object of the present invention is to expand an injection valve for fuels, in particular for alternative fuels, in such a way that a larger inlet cross section is available for the corresponding fuel while the installation space requirement is largely unchanged.

[0006] To achieve this object, an injection valve having the features of claim 1, a cylinder head having the features of claim 5, and a method having the features of claim 8 are proposed. Advantageous developments of the invention can be derived from the corresponding dependent claims. In addition, the use of a cylindrical receptacle of a cylinder head as a housing for an injection valve is proposed.

[0007] The proposed injection valve for fuels, in particular for liquid fuels such as methanol and / or gaseous fuels such as natural gas or hydrogen, is designed for installation in a cylindrical receptacle of a cylinder head. The injection valve comprises a body component with a peripheral recess which, after the injection valve is installed, forms with the cylindrical receptacle of the cylinder head an inlet path for the fuel which is designed as an annular space.

[0008] In the proposed injection valve, the cylindrical receptacle of the cylinder head serves as a housing for the injection valve. Therefore, until the injection valve is installed in the cylindrical receptacle of the cylinder head, the inlet path is not surrounded by a housing in the region of the peripheral recess of the body component of the injection valve, since such a housing is absent. The omission of the housing makes it possible to increase the inlet cross section of the inlet path while keeping the outer diameter of the injection valve constant, so that the installation space requirement of the injection valve remains constant.

[0009] After the injection valve is installed in the cylindrical receptacle of the cylinder head, the receptacle and the peripheral recess of the body component of the injection valve form an inlet path designed as an annular space. The configuration of the inlet path as an annular space and also as an annular space extending to the outside on the outer diameter of the injection valve makes it possible to maximize the inlet cross section.

[0010] The proposed injection valve is particularly suitable for injecting alternative fuels, such as methanol, natural gas or hydrogen, since the enlarged inlet cross section of the inlet path can compensate for the low inlet pressure and / or the low energy density of such fuels.

[0011] According to a preferred embodiment of the present invention, the inlet path is configured as an internal inlet channel upstream and downstream of the peripheral recess of the body component. This means that the inlet path also has an internal section. Fuel can be introduced into the section implemented as an annular space through the internal section and discharged again to deliver the fuel to at least one injection opening of the injection valve.

[0012] It is further preferred that the inlet path is divided at least in sections into at least two paths extending substantially in parallel. This measure can further increase the inlet cross section. Preferably, the inlet channel on the inside forms the first path, and the annular space formed by the peripheral recess together with the cylindrical receiving portion forms the second path. The inlet path on the inside is then widened by the annular space on the outside.

[0013] Preferably, the injection valve has at least one sealing ring on the outside. With the aid of this sealing ring, the inlet path can be sealed to the outside after the injection valve is installed in the cylindrical receiving portion of the cylinder head. Preferably, at least one sealing ring is provided on both sides (both ends) of the peripheral recess of the body component, so that the annular space is sealed from both ends.

[0014] Furthermore, a cylinder head with a cylindrical receptacle for an internal combustion engine is proposed. The injection valve according to the invention for injecting fuel into a combustion chamber of the internal combustion engine is placed in the cylindrical receptacle, so that the cylindrical receptacle forms an inlet path implemented as an annular space together with a body component of the injection valve with a peripheral recess. The inlet path is thus delimited radially on the outside by the cylindrical receptacle of the cylinder head, so that the cylindrical receptacle replaces the missing housing of the injection valve. As a result, the inlet path is surrounded on all sides and can be loaded with fuel.

[0015] Preferably, the cylindrical receptacle is formed by a water jacket integrated into the cylinder head, which separates the inlet path, which is implemented as an annular space, from the cooling water channel formed in the cylinder head. The task of the water jacket integrated into the cylinder head is usually to seal the cooling water channel formed in the cylinder head relative to the combustion chamber. The cooling water guided via the cooling water channel is required to cool the injection valve. In the cylinder head according to the invention, the water jacket has another task. This task is to replace the missing housing of the injection valve. The space thus obtained in the injection valve is used as the inlet cross section.

[0016] Therefore, when the injection valve is in operation, the water jacket is acted upon by fuel on the one hand and by cooling water on the other hand. Accordingly, the requirements for sealing and the requirements for reliable separation of media are increased.

[0017] Therefore, as an extended measure, it is proposed that at least one sealing ring is arranged between the water jacket and the cylinder head. The at least one sealing ring seals the cooling water channel outwardly and toward the combustion chamber. In order to seal the inlet path embodied as an annular space, at least one sealing ring on the outside of the injection valve can be used, which seals against the water jacket of the cylinder head under the action of a radial preload. Preferably, the injection valve has at least two sealing rings on the outside, which are arranged on both sides of the annular space. In this way, a reliable separation of the medium can be achieved at the same time.

[0018] In a method for installing an injection valve according to the invention in a cylinder head, the injection valve is inserted into a cylindrical receptacle of the cylinder head, so that the cylindrical receptacle and a body component of the injection valve having a peripheral recess together form an inlet path designed as an annular space. When the injection valve is installed in the cylinder head accordingly, the cylindrical receptacle of the cylinder head replaces the missing housing of the injection valve. The omission of the housing and the configuration of the inlet path as an annular space make it possible to achieve a large inlet cross section while maintaining the installation space requirement of the injection valve.

[0019] As a further development, it is proposed that a water jacket is inserted into the cylinder head before the injection valve is installed in order to form the cylindrical receptacle and to seal the cooling water channel formed in the cylinder head. After the injection valve is installed, the water jacket separates the inlet path, which is designed as an annular space, from the cooling water channel. The water jacket thus simultaneously serves to separate the medium, namely the cooling water from the fuel.

[0020] Advantageously, at least one sealing ring is arranged between the injection valve and the cylindrical receptacle of the cylinder head or the water jacket forming the cylindrical receptacle. By means of the at least one sealing ring, the inlet path implemented as an annular space can be sealed, thereby ensuring the tightness of the injection valve. Preferably, at least one sealing ring is arranged on both sides of the annular space.

[0021] Furthermore, it is proposed to use a cylindrical receptacle of the cylinder head, which is preferably formed by a water jacket integrated into the cylinder head, as a housing for the injection valve according to the invention inserted into the cylinder head. The housing which is missing for the injection valve according to the invention is then replaced by the cylindrical receptacle of the cylinder head or the water jacket integrated into the cylinder head. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] A preferred embodiment of the present invention is described in more detail below with reference to the accompanying drawings. The accompanying drawings show:

[0023] Figure 1 shows a schematic longitudinal section through an injection valve according to the invention, and

[0024] Figure 2 Show Figure 1 Schematic longitudinal section through an injection valve in FIG. 1 with a representation of the fuel supply. DETAILED DESCRIPTION

[0025] from Figure 1 In the figure, an injection valve 1 for fuel can be seen, which is inserted into a cylinder head 6 of an internal combustion engine. In the cylinder head 6, in the region of the injection valve 1, a cooling water channel 8 is formed, which is sealed to the outside by a water jacket and by a sealing ring 9 arranged between the water jacket and the cylinder head 6.

[0026] The water jacket forms a cylindrical receptacle 7, into which the injection valve 1 is inserted. The water jacket replaces the missing housing of the injection valve 1. Instead of the housing, the injection valve 1 comprises a body component 4 with a peripheral recess 3, which together with the water jacket of the cylinder head 6 forms an annular space. The inlet path 2 of the injection valve 1 extends through the annular space, so that fuel can be supplied to at least one injection opening (not shown) of the injection valve 1 via the annular space.

[0027] Before the injection valve 1 is inserted into the cylindrical receptacle 7 of the cylinder head 6, the inlet path 2 is not surrounded on all sides. Therefore, the inlet path 2 cannot be charged with fuel before the injection valve 1 is installed. After the injection valve 1 is installed in the cylinder head 6, the water jacket and the sealing ring 5 arranged on the injection valve 1 seal the inlet path 2 to the outside.

[0028] from Figure 2 You can see Figure 1 The injection valve 1 during loading with fuel. The inlet path 2 first extends inwardly and then widens due to the annular space formed on the outside by the peripheral recess 3 of the body component 4 and the cylindrical receptacle 7 in the form of a water jacket. A further section of the inlet path 2 adjoins the annular space and in turn extends inwardly in order to deliver the fuel to at least one injection opening (not shown) of the injection valve 1. The flow of the fuel is guided in Figure 2 Indicated by arrows.

[0029] Since the inlet path 2 for the fuel extends to the outer diameter of the injection valve 1, the inlet cross section of the inlet path 2 can be maximized. In this way, a low inlet pressure and / or a low energy density of the alternative fuel can be compensated, making the injection valve 1 particularly suitable for injecting such fuels.

[0030] The terms "radially outer" and "radially inner" are respectively referred to the axis A forming the central longitudinal axis of the injection valve 1. The peripheral recessed portion 3 in the body member 4 extends in the axial direction, that is, in a direction parallel to the axis A. Therefore, the sealing rings 5 ​​arranged on both sides of the recessed portion 3 are arranged in a manner spaced apart from each other by an axial distance.

Claims

1. An injection valve (1) for liquid or gaseous fuel, the injection valve being intended to be installed in a cylindrical receptacle (7) of a cylinder head (6), wherein: The injection valve (1) comprises a body component (4) having a peripheral recess (3) which, after the injection valve (1) is installed, forms together with a cylindrical receiving portion (7) of the cylinder head (6) an inlet path (2) for the fuel which is implemented as an annular space.

2. The injection valve (1) according to claim 1, characterized in that The inlet path (2) continues upstream and downstream of the recess (3) as an internal inlet channel.

3. The injection valve (1) according to claim 1 or 2, characterized in that The inlet path (2) is divided at least in sections into at least two paths extending substantially in parallel, wherein preferably the inner inlet channel forms a first path and the annular space formed by the recess (3) together with the cylindrical receptacle (7) forms a second path.

4. The injection valve (1) according to claim 1, characterized in that The injection valve (1) has at least one external sealing ring (5), wherein preferably at least one sealing ring (5) is arranged on each side of the recess (3).

5. The injection valve (1) according to claim 1, characterized in that The fuel is a liquid fuel, in particular methanol, or the fuel is a gaseous fuel, in particular natural gas or hydrogen.

6. A cylinder head (6) for an internal combustion engine, the cylinder head having a cylindrical receptacle (7), into which an injection valve (1) according to one of the above claims for injecting fuel into a combustion chamber of the internal combustion engine is inserted, so that the cylindrical receptacle (7) and a body component (4) of the injection valve (1) having a peripheral recess (3) form an inlet path (2) implemented as an annular space.

7. The cylinder head (6) according to claim 6, characterized in that The cylindrical receptacle (7) is formed by a water jacket integrated into the cylinder head (6), which separates the inlet path (2) designed as an annular space from a cooling water channel (8) formed in the cylinder head (6).

8. The cylinder head (6) according to claim 7, characterized in that At least one sealing ring (9) is arranged between the water jacket and the cylinder head (6).

9. A method for installing an injection valve (1) according to one of claims 1 to 4 into a cylinder head (6), in which the injection valve (1) is placed in a cylindrical receptacle (7) of the cylinder head (6) so that the cylindrical receptacle (7) together with a body component (4) of the injection valve (1) having a peripheral recess (3) forms the inlet path (2) implemented as an annular space.

10. The method according to claim 9, characterized in that In order to form the cylindrical receptacle (7) and to seal the cooling water channel (8) formed in the cylinder head (6), a water jacket (7) is inserted into the cylinder head (6) before the injection valve (1) is installed.

11. The method according to claim 9 or 10, characterized in that: At least one sealing ring (5) is arranged between the injection valve (1) and the cylindrical receptacle (7).

12. Use of a cylindrical receptacle (7) of a cylinder head (6) as a housing for an injection valve (1) according to one of claims 1 to 4 inserted into the cylinder head (6), the cylindrical receptacle preferably being formed by a water jacket integrated into the cylinder head (6).

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