Injection valve for fuel, cylinder head with injection valve, method for mounting the injection valve in a cylinder head, and use of a cylindrical receiving part of a cylinder head as an outer cover for the injection valve

Abstract

The present invention relates to an injection valve (1) for a fuel, in particular a liquid fuel such as methanol, and / or a gaseous fuel such as natural gas or hydrogen, for installation in a cylindrical receiving portion (7) of a cylinder head (6), wherein the injection valve (1) has a body component (4) with a reset portion (3) on its outer circumferential surface, which, together with the cylindrical receiving portion (7) of the cylinder head (6), after installation of the injection valve (1), forms a supply passage (2) for the fuel configured as an annular chamber. The present invention also relates to a cylinder head (6) equipped with the injection valve (1) according to the present invention, a method for installing the injection valve (1) according to the present invention in the cylinder head (6), and a use of the cylindrical receiving portion (7) of the cylinder head (6) as an outer cover for the injection valve (1).

Description

[Technical Field]

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

[0002] The invention therefore also relates to a cylinder head with an injection valve according to the invention, which is inserted into a cylindrical receptacle in the cylinder head. Furthermore, a method for mounting the injection valve in the cylinder head and the use of the cylindrical receptacle in the cylinder head as an outer cover for the injection valve are proposed. [Background technology]

[0003] The prior art describes various embodiments of injection valves for liquid and / or gaseous fuels. These injection valves typically have a nozzle body and a nozzle needle accommodated in the nozzle body for stroke movement, via which at least one injection hole formed in the nozzle body can be controlled. Fuel reaches the at least one injection hole via an internal supply channel. The internal supply channel typically extends not only through the nozzle body but also through an injection valve holder axially integrated into the nozzle body and connected thereto via a nozzle clamping nut. In addition to the nozzle body and the holder, the injection valve may have other body components that are clamped together by the nozzle clamping nut.

[0004] To inject selective fuels, in particular liquid fuels such as methanol and / or gaseous fuels such as natural gas or hydrogen, a large inlet cross section is generally required due to the relatively low supply pressure and / or relatively low energy density of the fuel, because otherwise the required throughput of fuel would not be possible. A larger inlet cross section generally requires a larger outer diameter, which has a negative effect on the installation space of the injector. Summary of the Invention [Problem to be solved by the invention]

[0005] The object of the present invention is to further develop an injection valve for fuels, in particular for selected fuels, so that a larger inlet cross section for the respective fuel can be obtained while keeping the installation space requirement as small as possible. [Means for solving the problem]

[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. Preferred developments of the invention can be read from the respective dependent claims. Furthermore, it is proposed to use a cylindrical receiving part of the cylinder head as an outer cover for the injection valve.

[0007] The proposed injector for fuel, in particular for liquid fuel such as methanol and / or gaseous fuel such as natural gas or hydrogen, is designed to be mounted in a cylindrical receptacle in a cylinder head, and has a body component with a reset portion on its outer periphery, which, together with the cylindrical receptacle in the cylinder head after mounting of the injector, forms a supply channel for the fuel configured as an annular chamber.

[0008] In the proposed injection valve, the cylindrical receptacle of the cylinder head serves as an outer cover for the injection valve. Therefore, until the injection valve is installed in the cylindrical receptacle of the cylinder head, the supply passage is not enclosed by an outer cover in the area of ​​the reset portion on the outer peripheral surface of the body component of the injection valve, because the outer cover is not present. By eliminating the outer cover, the outer diameter of the injection valve remains the same, and the inlet cross section of the supply passage can be enlarged, so the installation space required for the injection valve remains unchanged.

[0009] After the injection valve is mounted in the cylindrical receiving part of the cylinder head, the receiving part and the outer peripheral reset part of the injection valve body part form a supply channel configured as an annular chamber. The configuration of the supply channel as an annular chamber, and in particular as an outer annular chamber extending to the outer diameter of the injection valve, allows the inlet cross section to be maximized.

[0010] The proposed injector is particularly suitable for injecting selected fuels, such as methanol, natural gas or hydrogen, since the enlarged inlet cross section of the supply channel can compensate for the lower supply pressure and / or the lower energy density of such fuel types.

[0011] According to a preferred embodiment of the invention, the supply channel is configured as an inner supply channel upstream and downstream of the reset point on the outer circumferential surface of the body component, i.e., the supply channel also has an inner section, via which fuel can be introduced into and removed from the section configured as an annular chamber in order to supply fuel to at least one injection orifice of the injection valve.

[0012] More preferably, the supply channel is divided at least in sections into at least two generally parallel flow paths. By this measure, the inlet cross section can be further enlarged. In a preferred embodiment, the inner supply channel forms the first flow path, and the annular chamber formed by the outer peripheral reset portion and the cylindrical receiving portion together forms the second flow path. In this way, the inner supply channel is enlarged by the outer annular chamber.

[0013] Preferably, the injection valve has at least one externally positioned sealing ring, by means of which the supply passage can be sealed against the outside after the injection valve has been mounted in the cylindrical receiving part of the cylinder head. Preferably, at least one sealing ring is provided on each side of the reset part on the outer circumferential surface of the body part, so that the annular chamber is subsequently sealed from both ends.

[0014] Furthermore, a cylinder head for an internal combustion engine is proposed, which has a cylindrical receiving portion into which an injector according to the present invention for injecting fuel into a combustion chamber of the internal combustion engine is inserted, whereby the cylindrical receiving portion and a body component of the injector having an outer peripheral reset portion together form a supply channel configured as an annular chamber. The supply channel is thus bounded radially outward by the cylindrical receiving portion of the cylinder head, which compensates for the absence of an outer cover for the injector. The supply channel is thus completely surrounded and can be loaded with fuel.

[0015] Preferably, the cylindrical receiving portion is formed by a water sleeve integrated into the cylinder head, which separates the supply passage configured as an annular chamber from the cooling water passage formed in the cylinder head. The purpose of a water sleeve integrated into the cylinder head is usually to seal the cooling water passage formed in the cylinder head from the combustion chamber. The cooling water guided through the cooling water passage is required to cool the injection valve. In the cylinder head according to the present invention, the water sleeve has another purpose: to compensate for the absence of an outer cover for the injection valve. The space thus obtained within the injection valve is utilized as an inlet cross section.

[0016] During operation of the injection valve, the water sleeve is therefore loaded on the one hand by fuel and on the other hand by cooling water, which places correspondingly high demands on the sealing properties and on reliable media separation.

[0017] Therefore, a further improvement is proposed: at least one sealing ring is disposed between the water sleeve and the cylinder head. The at least one sealing ring seals the cooling water passage from the outside and from the combustion chamber. To seal the supply passage configured as an annular chamber, at least one sealing ring located on the outside of the injector can be used, which radially abuts against the water sleeve of the cylinder head. Preferably, the injector has at least two sealing rings located on the outside, on both sides of the annular chamber. In this way, more reliable media separation can be achieved at the same time.

[0018] In a further proposed method for mounting an injector in a cylinder head according to the invention, the injector is inserted into a cylindrical receiving portion of the cylinder head, whereby the cylindrical receiving portion and the body portion of the injector having the outer circumferential reset portion together form a supply channel configured as an annular chamber. When the injector is mounted accordingly in the cylinder head, the cylindrical receiving portion of the cylinder head compensates for the absence of an outer cover of the injector. By eliminating the outer cover and by forming the supply channel as an annular chamber, a large inlet cross section is possible without changing the mounting space required for the injector.

[0019] As a further improvement, it is proposed that a water sleeve be inserted into the cylinder head before the injection valve is installed to form a cylindrical receptacle and seal the cooling water passage formed in the cylinder head. After the injection valve is installed, the water sleeve separates the supply passage configured as an annular chamber from the cooling water passage. Thus, the water sleeve simultaneously serves to separate the cooling water and fuel as media.

[0020] Preferably, at least one sealing ring is arranged between the injection valve and the cylindrical receiving portion of the cylinder head or the water sleeve forming the cylindrical receiving portion. The at least one sealing ring seals the supply passage configured as an annular chamber, thereby ensuring the sealing of the injection valve. Preferably, at least one sealing ring is arranged on each side of the annular chamber.

[0021] Furthermore, it is proposed to use the cylindrical receiving part of the cylinder head, preferably formed by a water sleeve integrated into the cylinder head, as an outer cover of the injector according to the invention integrated into the cylinder head, whereby the outer cover missing in the injector according to the invention is replaced by the cylindrical receiving part of the cylinder head or the water sleeve integrated into the cylinder head. [Brief explanation of the drawings]

[0022] [Figure 1] 1 is a schematic longitudinal section of an injection valve according to the invention; [Figure 2] 2 is a schematic longitudinal cross-sectional view of the injection valve of FIG. 1, showing the fuel guide; DETAILED DESCRIPTION OF THE INVENTION

[0023] Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0024] 1 shows an injection valve 1 for fuel inserted into a cylinder head 6 of an internal combustion engine. A cooling water passage 8 is formed in the area of ​​the injection valve 1 in the cylinder head 6, and this cooling water passage 8 is sealed outward by a water sleeve and a sealing ring 9, which is arranged between the water sleeve and the cylinder head 6.

[0025] The water sleeve forms a cylindrical receiving portion 7 into which the injection valve 1 is inserted. The water sleeve replaces the outer cover that is missing from the injection valve 1. Instead of the outer cover, the injection valve 1 has a body component 4 with a reset portion 3 on its outer peripheral surface, and this reset portion 3 forms an annular chamber together with the water sleeve in the cylinder head 6. The supply passage 2 of the injection valve 1 communicates with the annular chamber, so that fuel can be supplied via the annular chamber of at least one injection hole (not shown) of the injection valve 1.

[0026] Before the injection valve 1 is inserted into the cylindrical receptacle 7 of the cylinder head 6, the supply passage 2 is not completely enclosed, and therefore cannot be loaded with fuel before the injection valve 1 is inserted. After the injection valve 1 is inserted into the cylinder head 6, the water sleeve and the sealing ring 5 arranged on the injection valve 1 seal the supply passage 2 from the outside.

[0027] Figure 2 shows the injector 1 of Figure 1 while it is being loaded with fuel. The supply channel 2 is first guided through the inside and then widens via an annular chamber located on the outside. This annular chamber is formed by the outer reset 3 of the body part 4 and a cylindrical receiving part 7 in the form of a water sleeve. A further section of the supply channel 2 follows this annular chamber and is again guided inwards to supply fuel to at least one injection hole (not shown) of the injector 1. The fuel flow direction is indicated by arrows in Figure 2.

[0028] The inlet cross section of the supply line 2 for the fuel can be maximized by guiding the supply line 2 to the outer diameter of the injector 1. In this way, the low supply pressure and / or low energy density of selected fuels can be compensated for, so that the injector 1 is particularly suitable for injecting such fuels.

[0029] The terms "radially outward" and "radially inward" respectively relate to the axis A which forms the central longitudinal axis of the injection valve 1. The outer peripheral reset portion 3 in the body part 4 extends axially, i.e. parallel to the axis A. The sealing rings 5 ​​arranged on both sides of the reset portion 3 are therefore spaced apart from each other in the axial direction. [Explanation of symbols]

[0030] 1 injection valve 2 Supply route 3 Reset section 4 Body components 5 seal ring 6. Cylinder head 7 Cylindrical receiving part, water sleeve 8 Cooling water flow path 9 Seal ring

Claims

1. An injection valve (1) for liquid or gaseous fuel to be mounted in a cylindrical receiving portion (7) of a cylinder head (6), the injection valve (1) having a body component (4) with a reset portion (3) on its outer circumferential surface side, the reset portion (3) forming, together with the cylindrical receiving portion (7) of the cylinder head (6), a supply passage (2) for fuel configured as an annular chamber after the injection valve (1) is mounted.

2. 2. The injection valve (1) according to claim 1, characterized in that the supply channel (2) extends as an inner supply channel upstream and downstream of the reset part (3).

3. 3. The injection valve (1) according to claim 1 or 2, characterized in that the supply channel (2) is divided at least in sections into at least two flow paths guided approximately in parallel, the supply channel located in a preferred manner being the inner one forming a first flow path, and the annular chamber formed by the cylindrical receiving portion (7) together with the reset portion (3) forming a second flow path.

4. The injection valve (1) according to any one of claims 1 to 3, characterized in that the injection valve (1) has at least one sealing ring (5) positioned on the outside, preferably at least one sealing ring (5) is provided on each side of the reset portion (3).

5. 5. An injection valve (1) according to any one of claims 1 to 4, characterized in that the fuel is a liquid fuel, in particular methanol, or a gaseous fuel, in particular natural gas or hydrogen.

6. A cylinder head (6) for an internal combustion engine having a cylindrical receiving portion (7), 1. A cylinder head (6) in which an injection valve (1) according to any one of claims 1 to 5 for injecting fuel into a combustion chamber of an internal combustion engine is fitted into the receiving portion (7), whereby the cylindrical receiving portion (7) and the body component (4) of the injection valve (1) having the reset portion (3) on the outer peripheral surface side form a supply passage (2) configured as an annular chamber.

7. 7. The cylinder head (6) according to claim 6, characterized in that the cylindrical receiving portion (7) is formed by a water sleeve integrated into the cylinder head (6), the water sleeve separating the supply passage (2) configured as an annular chamber from a cooling water flow passage (8) formed in the cylinder head (6).

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

9. 5. A method for mounting an injection valve (1) in a cylinder head (6) according to any one of claims 1 to 4, comprising: A method for mounting an injection valve (1), comprising inserting the injection valve (1) into a cylindrical receiving portion (7) of the cylinder head (6), so that the cylindrical receiving portion (7) and the body component (4) of the injection valve (1), which has the reset portion (3) on its outer circumferential surface side, jointly form the supply passage (2) configured as an annular chamber.

10. 10. The method according to claim 9, further comprising inserting a water sleeve (7) into the cylinder head (6) before mounting the injection valve (1) in order to form the cylindrical receiving portion (7) and seal the cooling water passage (8) formed in the cylinder head (6).

11. 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 receiving part (7).

12. Use of a cylindrical receptacle (7) in a cylinder head (6), preferably formed by a water sleeve incorporated in said cylinder head (6), 5. Use of a cylindrical receiving part (7) of a cylinder head (6), the receiving part (7) being used as an outer cover of an injection valve (1) according to any one of claims 1 to 4, which is integrated into the cylinder head (6).

Images