Injection valve for fuels, cylinder head having an injection valve, method for installing an injection valve in a cylinder head, and use of a cylindrical receptacle of a cylinder head as an outer sleeve of an injection valve

Abstract

The invention relates to an injection valve (1) for fuels, in particular for liquid fuels, such as methanol, and / or for gaseous fuels, such as natural gas or hydrogen, for installing in a cylindrical receptacle (7) of a cylinder head (6), the injection valve (1) having a body component (4) with an outer-circumference recess (3), which, after the injection valve (1) has been installed, forms an inflow path (2) for a fuel together with the cylindrical receptacle (7) of the cylinder head (6), said inflow path being in the form of an annular space. The invention also 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 a use of a cylindrical receptacle (7) of a cylinder head (6) as an outer sleeve of an injection valve (1).

Description

[0001] Description

[0002] Title:

[0003] Fuel injection valve, cylinder head with injection valve, method for installing an injection valve in a cylinder head and use of a cylindrical receptacle of a cylinder head as the outer shell of an injection valve

[0004] The invention relates to an injection valve for fuels, in particular for liquid fuels, such as methanol, and / or for gaseous fuels, such as natural gas or hydrogen. The injection valve can be used to inject the fuels into a combustion chamber of an internal combustion engine. For this purpose, the injection valve is installed in a cylinder head of the internal combustion engine.

[0005] The invention therefore further relates to a cylinder head with an injection valve according to the invention which is inserted into a cylindrical receptacle of the cylinder head.

[0006] Furthermore, a method for installing an injection valve in a cylinder head and a use of a cylindrical receptacle of a cylinder head as an outer shell of an injection valve are proposed.

[0007] State of the art

[0008] Injectors for liquid and / or gaseous fuels are described in the prior art in a wide variety of designs. They generally comprise a nozzle body and a nozzle needle accommodated in the nozzle body for lifting movement, the lifting movements of which control at least one injection opening formed in the nozzle body. The fuel reaches the at least one injection opening via an internal inlet channel, which generally extends not only over the nozzle body but also over a holding body of the injection valve, which is attached axially to the nozzle body and connected to the nozzle body via a nozzle clamping nut. In addition to a nozzle body and a holding body, the injection valve can have further body components that are clamped together by means of the nozzle clamping nut.

[0009] To inject alternative fuels, especially 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 lower inlet pressure and / or lower energy density of the fuel. Otherwise, the required fuel throughput cannot be achieved. Larger inlet cross-sections generally require larger outer diameters, which negatively impacts the space required for the injector.

[0010] The present invention is concerned with the object of developing an injection valve for fuels, in particular for alternative fuels, in such a way that a larger inlet cross-section for the respective fuel is created while keeping the installation space requirement as unchanged as possible.

[0011] To achieve this objective, the injection valve having the features of claim 1, the cylinder head having the features of claim 5, and the method having the features of claim 8 are proposed. Advantageous further developments of the invention can be found in the respective subclaims. Furthermore, the use of a cylindrical cylinder head receptacle as the outer shell of an injection valve is proposed.

[0012] Disclosure of the invention

[0013] The proposed fuel injector for fuels, in particular liquid fuels such as methanol, and / or gaseous fuels such as natural gas or hydrogen, is designed for installation in a cylindrical housing of a cylinder head. The injector comprises a body component with an outer peripheral recess which, after installation of the injector, together with the cylindrical housing of the cylinder head, forms an inlet path for a fuel in the form of an annular space.

[0014] In the proposed injector, the cylindrical housing of the cylinder head serves as the injector's outer shell. Until the injector is installed in the cylindrical housing of the cylinder head, the inlet path in the area of ​​the outer circumferential recess of the injector body component is therefore not enclosed by an outer shell, as one is missing. Eliminating the outer shell allows for an increase in the inlet cross-section of the inlet path while maintaining the same outer diameter of the injector, so that the injector's installation space remains unchanged.

[0015] After the injector is installed in the cylindrical housing of the cylinder head, the housing and the outer peripheral recess of the injector body component form an inlet path designed as an annular space. The design of the inlet path as an annular space, and also as an external annular space extending to the outer diameter of the injector, enables the inlet cross-section to be maximized.

[0016] The proposed injection valve is particularly suitable for injecting alternative fuels, such as methanol, natural gas or hydrogen, because the enlarged inlet cross-section of the inlet path can compensate for the lower inlet pressure and / or the lower energy density of such fuels.

[0017] According to a preferred embodiment of the invention, the inlet path is designed as an internal inlet channel upstream and downstream of the outer peripheral recess of the body component. This means that the inlet path also has internal sections. The fuel can be introduced into the section designed as an annular space and discharged again via the internal sections in order to supply the fuel to at least one injection opening of the injection valve.

[0018] Furthermore, the inlet path is preferably divided, at least in sections, into at least two essentially parallel paths. This measure allows the inlet cross-section to be further enlarged. An internal inlet channel preferably forms a first path, and the annular space formed by the outer circumferential recess together with the cylindrical receptacle forms a second path. The internal inlet channel is then widened by the outer annular space. The injection valve preferably has at least one external sealing ring. With the aid of the sealing ring, the inlet path can be sealed to the outside after the injection valve has been installed in the cylindrical receptacle of the cylinder head. Preferably, at least one sealing ring is provided on either side of the outer circumferential recess of the body component, so that the annular space is subsequently sealed from both ends.

[0019] Furthermore, a cylinder head for an internal combustion engine with a cylindrical receptacle is proposed. An inventive injection valve for injecting fuel into a combustion chamber of the internal combustion engine is inserted into the cylindrical receptacle, so that the cylindrical receptacle and the body component of the injection valve having the outer circumferential recess together form the inlet path designed as an annular space. 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 outer shell of the injection valve. The inlet path is thus enclosed on all sides and can be supplied with fuel.

[0020] The cylindrical receptacle is preferably formed by a water sleeve integrated into the cylinder head, which separates the inlet path, designed as an annular space, from a cooling water channel formed in the cylinder head. The function of a water sleeve integrated into the cylinder head is usually to seal the cooling water channel formed in the cylinder head from the combustion chamber. The cooling water conducted via the cooling water channel is required to cool the injection valve. In a cylinder head according to the invention, the water sleeve has a further function. This is to replace the missing outer shell of the injection valve. The space thus gained in the injection valve is used as the inlet cross-section.

[0021] During operation of the injection valve, the water sleeve is exposed to fuel on the one hand and cooling water on the other. Accordingly, the sealing requirements and the demands for reliable media separation increase.

[0022] As a further development, it is therefore proposed that at least one sealing ring be arranged between the water sleeve and the cylinder head. The at least one sealing ring seals the cooling water channel to the outside and to the combustion chamber. To seal the inlet path, which is designed as an annular space, at least one external sealing ring of the injection valve can be used, which rests against the water sleeve of the cylinder head under radial preload. The injection valve preferably has at least two external sealing rings arranged on either side of the annular space. In this way, reliable media separation can be achieved at the same time.

[0023] In the further proposed method for installing an injector according to the invention in a cylinder head, the injector is inserted into a cylindrical receptacle of the cylinder head, so that the cylindrical receptacle and the body component of the injector having the outer circumferential recess together form the inlet pad designed as an annular space. When the injector is installed in the cylinder head accordingly, the cylindrical receptacle of the cylinder head replaces the missing outer shell of the injector. The omission of the outer shell and the design of the inlet path as an annular space enables large inlet cross-sections while maintaining the same installation space requirements for the injector.

[0024] As a further development, it is proposed that a water sleeve be inserted into the cylinder head prior to installing the injection valve to form the cylindrical mount and seal a cooling water channel. After the injection valve is installed, the water sleeve separates the inlet path, which is designed as an annular space, from the cooling water channel. The water sleeve thus also serves to separate the cooling water and fuel media.

[0025] Advantageously, at least one sealing ring is arranged between the injection valve and the cylindrical housing of the cylinder head or the water sleeve forming the cylindrical housing. The at least one sealing ring can be used to seal the inlet path, which is designed as an annular space, thus ensuring the tightness of the injection valve. Preferably, at least one sealing ring is arranged on each side of the annular space.

[0026] Furthermore, the use of a cylindrical cylinder head receptacle, preferably formed by a water sleeve integrated into the cylinder head, as the outer shell of an injection valve according to the invention inserted into the cylinder head is proposed. The outer shell missing from the injection valve according to the invention is then replaced by the cylindrical cylinder head receptacle or the water sleeve integrated into the cylinder head.

[0027] A preferred embodiment of the invention is explained in more detail below with reference to the accompanying drawings. These show:

[0028] Fig. 1 is a schematic longitudinal section through an injection valve according to the invention and

[0029] Fig. 2 is a schematic longitudinal section through the injection valve of Figure 1 showing the fuel supply.

[0030] Detailed description of the drawings

[0031] Figure 1 shows a fuel injection valve 1 installed in a cylinder head 6 of an internal combustion engine. A cooling water channel 8 is formed in the cylinder head 6 in the area of ​​the injection valve 1, which is sealed to the outside by a water sleeve and by sealing rings 9 arranged between the water sleeve and the cylinder head 6.

[0032] The water sleeve forms a cylindrical receptacle 7 into which the injection valve 1 is inserted. The water sleeve replaces a missing outer shell of the injection valve 1. Instead of an outer shell, the injection valve 1 has a body component 4 with an outer peripheral recess 3, which, together with the water sleeve of the cylinder head 6, forms an annular space. An inlet path 2 of the injection valve 1 leads over 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.

[0033] Before the injection valve 1 is inserted into the cylindrical receptacle 7 of the cylinder head 6, the inlet path 2 is not enclosed on all sides. The inlet path 2 cannot therefore be supplied with fuel before the injection valve 1 is installed. After the injection valve 1 is installed in the cylinder head 6, the water sleeve and sealing rings 5 ​​arranged on the injection valve 1 seal the inlet path 2 to the outside. Figure 2 shows the injection valve 1 of Figure 1 during the supply of fuel. The inlet path 2 is initially guided internally and then expands via the external annular space formed by the outer circumferential recess 3 of the body component 4 and the cylindrical receptacle 7 in the form of the water sleeve.The annular space is followed by another section of the inlet path 2, which is again directed inward to supply the fuel to the at least one injection opening (not shown) of the injection valve 1. The flow of the fuel is illustrated in Figure 2 by arrows.

[0034] Because the fuel inlet path 2 extends to the outer diameter of the injector 1, the inlet cross-section of the inlet path 2 can be maximized. In this way, low inlet pressures and / or low energy densities of alternative fuels can be compensated, making the injector 1 particularly suitable for injecting such fuels.

[0035] The terms "radially outer" and "radially inner" respectively refer to an axis A, which forms the central longitudinal axis of the injection valve 1. The outer peripheral recess 3 in the body component 4 extends in the axial direction, i.e., in a direction parallel to the axis A. The sealing rings 5 ​​arranged on either side of the recess 3 are accordingly arranged at an axial distance from one another.

Claims

Claims 1. Injection valve (1) for liquid or gaseous fuels for installation in a cylindrical receptacle (7) of a cylinder head (6), wherein the injection valve (1) has a body component (4) with an outer peripheral recess (3) which, after installation of the injection valve (1), together with the cylindrical receptacle (7) of the cylinder head (6), forms an inlet path (2) for a fuel in the form of an annular space.

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

3. 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 substantially parallel paths, wherein preferably an internal 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. Injection valve (1) according to one of the preceding claims, characterized in that the injection valve (1) has at least one external sealing ring (5), wherein preferably at least one sealing ring (5) is provided on both sides of the recess (3).

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

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

7. Cylinder head (6) according to claim 6, characterized in that the cylindrical receptacle (7) is formed by a water sleeve 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. 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. Method for installing an injection valve (1) according to one of claims 1 to 4 in a cylinder head (6), in which the injection valve (1) is inserted into a cylindrical receptacle (7) of the cylinder head (6), so that the cylindrical receptacle (7) and the body component (4) of the injection valve (1) having the outer peripheral recess (3) together form the inlet path (2) designed as an annular space.

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

11. 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), which is preferably formed by a water sleeve integrated into the cylinder head (6), as an outer shell of an injection valve (1) inserted into the cylinder head (6) according to one of claims 1 to 4.

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