Cylinder head for internal combustion engine and internal combustion engine equipped with said cylinder head

Abstract

To provide a cylinder head for an internal combustion engine, in particular a hydrogen-powered internal combustion engine, including: a cylinder head arrangement having an intake port (7); an injector (18) connected to the cylinder head arrangement; and an injection tube (19) extending along a tube core axis (L19) into the intake port (7) and fluidly connected to the injector (18).SOLUTION: An attachment element (21) having an air guiding portion (25, 26, 23) is arranged on the injection tube (19). The attachment element (21) extends radially outwards with respect to the tube core axis (L19) such that a flow in the intake port (7) is influenced by the air guiding portion (25, 26, 23).SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a cylinder head for an internal combustion engine and an internal combustion engine equipped with the cylinder head. [Background technology]

[0002] The cylinder head of an internal combustion engine defines the combustion chamber opposite the piston and typically contains the intake and exhaust ports, as well as the valve controls for the gas exchange process in the engine. In a port-injected engine, fuel is injected into the intake port, where it forms a mixture with the intake air.

[0003] An internal combustion engine with intake port injection is known from [Patent Document 1] (EP 0 694 124 B1), in which fuel is injected into the intake port via a tube.

[0004] The end of the tube that opens into the intake port contains an atomizing screen that atomizes the fuel exiting the tube to improve mixing. A drawback of this method is that the atomizing screen can become clogged during continuous operation, compromising fuel delivery. Additionally, especially when using hydrogen as fuel, the atomizing screen can trap fuel within the tube, creating a risk of unintended re-ignition within the tube.

[0005] [Patent Document 2] (JP 2003-214259 A) describes a cylinder head for an internal combustion engine, which has an intake port and an injector connected to the cylinder head. A tubular injection tube extends through the intake port and is fluidly connected to the injector. A C-shaped fastening ring and a collar element welded to the fastening ring are disposed within the intake port. The fastening ring is made of a spring material and is shaped to fit into a groove formed in the injector body at the downstream end of the intake port.

[0006] [Patent Document 3] (International Publication No. 2019 / 147963) discloses an injector with a nozzle head integrated into the cylinder head body. The fuel is mixed with air from the injector's air supply inside the injection nozzle before exiting the nozzle head. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] European Patent Publication No. 0 694 124 B1 [Patent Document 2] Japanese Patent Application Laid-Open No. 2003-214259 [Patent Document 3] International Publication No. 2019 / 147963 Brochure Summary of the Invention [Problem to be solved by the invention]

[0008] The object of the present invention is to provide a cylinder head for an internal combustion engine that is based on the above-mentioned known technology and that enables permanently good mixing in the intake port, and an internal combustion engine equipped with such a cylinder head. [Means for solving the problem]

[0009] In order to achieve the above object, the present invention provides a cylinder head for an internal combustion engine, in particular a hydrogen-powered internal combustion engine, comprising: a cylinder head arrangement including an intake port; an injector connected to the cylinder head arrangement; and a tubular injection tube fluidly connected to the injector and extending into the intake port along a tube core axis, wherein a mounting element is disposed on the injection tube, and the mounting element has an air guiding portion extending radially outward with respect to the tube core axis such that the flow in the intake port is affected by the air guiding portion.

[0010] The radially outward protruding air guide increases turbulence in the intake air downstream of the air guide. This turbulence improves mixing of the intake air with the fuel injected into the intake port through the injection tube. Because the air guide extends radially outward, the injection tube is not blocked by the air guide, and the injection tube does not become clogged or have fuel stagnation as operation progresses.

[0011] The intake port forms the final part of the engine's air induction system, connecting the intake manifold to the combustion chamber and is opened and closed by the intake valve.

[0012] In principle, an injector can function without a nozzle. The nozzle moves the point where the fuel enters the intake port flow from the wall bounding the intake port towards the center of the intake port. Therefore, the nozzle must be considered separately from the components of the injector required for general functioning.

[0013] In a possible embodiment, the radial extent of the air guide relative to the tube core axis may be greater than its axial extent in the direction of the tube core axis.

[0014] In particular, the air guide can be designed as an air baffle, the circumferential extension of which around the tube core axis can be smaller than the radial extension relative to the tube core axis. In another embodiment, the mounting element can have a first connection for positioning the mounting element on the injection pipe.

[0015] The air guide may extend radially outward from the first connection portion relative to the tube core axis.

[0016] In one embodiment, the radius of the minimum cylindrical envelope of the first connecting portion, whose cylindrical axis is arranged coaxially with the tube core axis, can be smaller than the maximum radial length of the air guide portion from the tube core axis.

[0017] In yet another embodiment, the mounting element can have a second connection portion that contacts the wall of the intake port. The first and second connection portions can be connected to each other via the air guide. Therefore, forces acting on the injection tube, such as inertial forces caused by external vibrations, can be supported by the mounting element at the wall of the intake port. This reduces stress on the injection tube, especially in the transition area with the injector, and extends the service life of the injection tube.

[0018] In yet another embodiment, the injection tube may have an injection port that opens into the intake port, and the attachment element may be positioned between the injector and the injection port.

[0019] In yet another embodiment, the cylinder head can include a first valve capable of selectively opening and closing the first combustion chamber inlet opening of the intake port. The first valve can include a valve disc and a valve shaft extending along the first valve axis. The inlet can be at least partially disposed within a minimum cylindrical envelope of the valve disc of the first valve, which is coaxial with the first valve axis. In other words, the inlet can be disposed within an imaginary cylinder defined by the bottom surface of the cylinder disc and the valve axis.

[0020] In yet another embodiment, the cylinder head may include a first valve capable of selectively opening and closing a first combustion chamber inlet opening of the intake port, and a second valve capable of selectively opening and closing a second combustion chamber inlet opening of the intake port, the first valve including a valve head and a valve shaft extending along a first valve axis, and the second valve including a valve head and a valve shaft extending along a second valve axis. In this case, the inlet may be positioned between a first imaginary plane perpendicular to the tube core axis described by the first valve axis and a second imaginary plane parallel to the first imaginary plane on which the second valve axis is positioned.

[0021] In order to solve the above problems, the present invention also proposes an internal combustion engine equipped with a cylinder head having the above configuration. [Brief explanation of the drawings]

[0022] [Figure 1] 1 is a schematic partial cross-sectional view of an internal combustion engine equipped with a first cylinder head according to the present invention; [Figure 2] FIG. 2 is a front view of the first mounting element of FIG. 1; [Figure 3] 4 is a cross-sectional view of the first mounting element taken along section line IV-IV in FIG. 2; [Figure 4] FIG. 2 is a front view of the second mounting element of FIG. 1; [Figure 5] 4A is a cross-sectional view of the second mounting element taken along section line IV-IV of FIG. 4; [Figure 6] 2 is a schematic partial cross-sectional view of an internal combustion engine equipped with a second cylinder head according to the present invention; DETAILED DESCRIPTION OF THE INVENTION

[0023] Hereinafter, possible embodiments of the cylinder head for an internal combustion engine of the present invention will be described with reference to the drawings.

[0024] 1 to 5 show an internal combustion engine 1. This internal combustion engine 1 operates using hydrogen as fuel in particular. The internal combustion engine 1 has a crankcase 2 connected to a cylinder head 5 of the present invention.

[0025] As is known, the crankcase 2 has a movable piston 4 and a variable combustion chamber 3 defined by a cylinder head 5. The cylinder head 5 has a cylinder head arrangement including a cylinder head base element 6 and a cylinder head cover (not shown), which are connected to each other.

[0026] An intake port 7 and an exhaust port 10 are cast into the cylinder head base element 6. An air-fuel mixture can be supplied to the combustion chamber 3 via the intake port 7. The intake port 7 has a wall 8, the boundary of which is defined by the wall 8, which is provided with a combustion chamber inlet opening 9 opening towards the combustion chamber 3. The combustion chamber inlet opening 9 can be selectively opened and closed in a known manner by an inlet valve 12. For this purpose, the inlet valve 12 has an inlet valve disc 13 which is arranged on a valve seat of the combustion chamber inlet opening 9 when the combustion chamber inlet opening 9 is closed, and an inlet valve shaft 14 which extends substantially cylindrically along an inlet valve axis L12. The inlet valve 12 can be moved along the inlet valve axis L12 by means of a corresponding valve train arranged above the cylinder head base element 6.

[0027] Exhaust gases produced by the combustion of an air-fuel mixture in the combustion chamber 3 can leave the combustion chamber 3 via an outlet port 10. The outlet port 10 has a wall and is bounded by the wall to form a combustion chamber. A combustion chamber outlet opening 11 opens toward the combustion chamber 3 and can be opened or closed as desired by an outlet valve 30 in a known manner. For this purpose, the exhaust valve 15 has a disk 16 which is arranged on a valve seat of the combustion chamber outlet opening 11 when the combustion chamber outlet opening 11 is closed, and a substantially cylindrical exhaust valve stem 17 which extends along a valve axis L15. The exhaust valve 15 is movable along the valve axis L15 by a valve train.

[0028] To form an air-fuel mixture, fuel is injected into the intake port 7 via an injector 18 connected to a cylinder head device, in particular the cylinder head base element 6, via connecting means (not shown). For this purpose, the outlet of the injector 18 is fluidly connected to an injection tube 19 extending into the intake port 7 along a tube core axis L19. The injection tube 19 has an injection port 20 opening into the intake port 7. In this case, the injection tube 19 is angled and has a first straight end facing the injector 18 and a second straight end facing the injection port 20, which are connected to each other via a curved section. The tube core axis L19 extends completely from one end of the injection tube 19 to the other. For clarity, in FIG. 1, the tube core axis L19 is shown only in the region of the second end. The tube core axis L19 could also have any other shape, such as being completely straight or S-shaped.

[0029] In the present invention, the mounting element 21 is arranged inside an imaginary straight cylinder, the bottom surface of which is described by the inlet valve disc 13 and which extends along the valve axis L12.

[0030] In the region of the second end of the injection tube 19, a first mounting element 21, shown in detail in FIGS. 2 and 3, and a second mounting element 21', shown in detail in FIGS. 4 and 5, are provided. The first mounting element 21 and the second mounting element 21' are respectively arranged between the injection hole 20 of the injection tube 19 and the injector 18. Here, the second mounting element 21' is arranged closer to the injection hole 20 than the first mounting element 21 along the tube core axis L19.

[0031] The first mounting element 21 has an annular first connecting portion 22, the inner contour of which is complementary to the outer contour of the filling pipe 19. The first mounting element 21 and the second mounting element 21' are rigidly connected to the filling pipe 19. In this case, the first mounting element 21 and the second mounting element 21' are press-fitted to the filling pipe 19. However, these two parts can also be joined in any other way, for example by brazing, gluing or pressing.

[0032] The first air guide section 24, the second air guide section 25, and the third air guide section 26 each extend radially outward from the first connecting section 22 relative to the tube core axis L19. Each of the three air guide sections 24, 25, and 26 extends radially relative to the tube core axis L19 more than axially. The circumferential length of each of the air guide sections 24, 25, and 26 around the tube core axis L19 is smaller than its radial and / or axial length, and therefore can be referred to as an air baffle. The air guide sections 24, 25, and 26 are shaped to affect the flow of intake air through the intake port 7.

[0033] In this case, the air guides 24, 25, 26 are designed as flat air guide plates or air guide baffles. However, the air guides 24, 25, 26 or air guide baffles can also have a shape other than flat, for example, they can be curved or twisted in the direction of the tube core axis L19. Therefore, the air guides 24, 25, 26 can cause the intake air flow in the intake port to have a swirling and / or tumbling motion.

[0034] The first mounting element 21 further comprises an annular second connecting portion 23 which contacts a region of the wall 8 of the intake port 7. In this case, the second connecting portion 23 is press-fitted into the intake port 7. However, the connecting portion 23 can also be joined to the wall 8 of the intake port 7 in a different way.

[0035] The first connecting portion 22 and the second connecting portion 23 are firmly connected to each other via the air guide portions 24, 25, and 26. Therefore, the injection pipe 19 is supported on the wall 8 of the intake port 7 via the first mounting element 21. This means that the forces acting on the injection pipe 19, such as the inertial force of the injection pipe 19 itself when the internal combustion engine 1 vibrates, can be supported by the mounting element 21. This reduces stress on the injection pipe 19 and extends the life of the injection pipe 19.

[0036] The second mounting element 21' differs from the first mounting element 21 only in that a fourth air guide 27 is provided in addition to the first air guide 24, the second air guide 25 and the third air guide 26. In this respect, what has been said above in relation to the first mounting element 21 also applies analogously to the second mounting element 21' in terms of similarities. Identical elements are provided with the same reference numerals.

[0037] The fourth air guide portion 27 is disposed obliquely with respect to the tube core axis L19. The fourth air guide portion 27 is disposed obliquely with respect to the tube core axis L19 along the tube core axis L19. Therefore, the distance between the fourth air guide portion 27 and the tube core axis L19 is not constant along the tube core axis L19. In particular, the distance between the fourth air guide portion 27 and the tube core axis L19 increases uniformly along the tube core axis L19.

[0038] The first and second mounting elements 21, 21' therefore affect the flow of intake air in the intake duct 27, improving mixing when fuel is injected into the intake port 7. Positioning the first and second mounting elements 21, 21' away from the inlet 20 of the injection pipe 19 does not reduce the cross-sectional area through which fuel can flow from the injection pipe 19 to the intake port 7, and therefore the flow of fuel through the injection pipe 19 is not reduced, and therefore the flow of fuel through the mounting elements 21, 21' is not impeded. Therefore, the remaining cross-sectional area may become clogged with increasing operating time.

[0039] It will be understood that instead of two mounting elements 21, 21', any combination of first mounting element 21 and second bottom element 21' can be provided depending on the application. In particular, only one first mounting element 21 or one second mounting element 21' can be provided.

[0040] [Figure 6] shows an internal combustion engine 1' in which the shape of the intake port 7' differs from the design of the internal combustion engine 1 of [Figure 1]. In [Figure 6], elements similar to those in [Figure 1] are given the same reference numerals. In this respect, what has been said in the context of [Figure 1] to [Figure 5] also applies to the internal combustion engine of [Figure 6] in terms of similarities.

[0041] An intake port 7' is cast into the cylinder head base element 6'. The outlet channel is not shown in [Fig. 6]. An air-fuel mixture can be supplied to the combustion chamber 3 via the intake port 7'. The intake port 7' is bounded by a wall 8' and has a first combustion chamber inlet opening 9 and a second combustion chamber inlet opening 9' that open towards the combustion chamber 3.

[0042] The first combustion chamber inlet opening 9 can be selectively opened and closed in a known manner by an inlet valve 12. For this purpose, the first inlet valve 12 comprises an inlet valve disc 13 which is arranged at a first valve seat of the first combustion chamber inlet opening 9 of the combustion chamber when the first combustion chamber inlet opening 9 is closed, and an inlet valve shaft 14 which extends in a substantially cylindrical shape along a valve axis L12. The first inlet valve 12 can be moved along the first valve axis L12 by means of a corresponding valve train arranged above the cylinder head base element 6.

[0043] The second combustion chamber inlet opening 9' can be selectively opened and closed by a second inlet valve 12' in a known manner. To this end, the second inlet valve 12' includes an inlet valve disc 13' that is disposed on a valve seat in the second combustion chamber inlet opening 9' when the second combustion chamber inlet opening 9' is closed, and an inlet valve shaft 14' that extends substantially cylindrically along a second valve axis L12'. The second inlet valve 12' can be moved along the second valve axis L12' by a valve train.

[0044] The injection port 20' of the injection pipe 19' is disposed between a first imaginary plane perpendicular to the tube core axis L19' described by the first valve axis L12 and a second imaginary plane extending parallel to the first imaginary plane in which the second valve axis L12' is disposed. [Explanation of symbols]

[0045] 1. Internal combustion engine 2 crankcase 3 Combustion chamber 4 pistons 5. Cylinder head 6 Cylinder head base element 7 Intake port 8. Wall 9 Combustion chamber inlet opening 10 Exhaust port 11 Combustion chamber exhaust port 12 Inlet valve 13 Inlet valve disc 14 Inlet valve shaft 15 Exhaust valve 16 Exhaust valve disc 17 Exhaust valve shaft 18 Injector 19 Injection tube 20 Inlet 21 Mounting elements 22 First connection part 23 Second connection part 24 First air guide section 25 Second air guide section 26 Third air guide section 27 Fourth air guide section L19 Tube core axis L12 Valve axis line L15 Valve axis line

Claims

1. a cylinder head device having an intake port (7), an injector (18) connected to the cylinder head device, a tubular injection pipe (19) extending into the intake port (7) along a tube core axis (L19) and fluidly connected to the injector (18), and a mounting element (21) arranged on the tubular injection pipe (19); the mounting element (21) has a first connecting portion (22), the mounting element (21) is disposed on the tubular injection pipe (19) by the first connecting portion (22), and air guide portions (25, 26, 27) extend radially outward from the first connecting portion (22) with respect to the tube core axis (L19) so that the flow in the intake port (7) is affected by the air guide portions (25, 26, 23); The mounting element (21) further has a second connection part (23) in contact with the wall (8) of the intake port (7), and the first connection part (22) and the second connection part (23) are connected to each other via air guide parts (25, 26, 27), which support a tubular injection pipe (19) on the wall (8) of the intake port (7) via the mounting element (21). A cylinder head for an internal combustion engine.

2. 10. The cylinder head of claim 1 for a hydrogen-powered internal combustion engine.

3. 2. A cylinder head according to claim 1, characterized in that the radial extent of the air guide portions (25, 26, 27) relative to the tube core axis (L19) is greater than their axial extent.

4. 2. A cylinder head according to claim 1, wherein the envelope of the first connecting portion (22), the cylindrical axis of which is arranged coaxially with the tube core axis (L19), has a radius smaller than the maximum radial distance of the air guide portions (25, 26, 27) from the tube core axis (L19).

5. A cylinder head as described in claim 1, wherein the tubular injection pipe (19) has an injection port (20) opening into the intake port (7), and a mounting element (21) is arranged between the injector (18) and the injection port (20).

6. 6. A cylinder head according to claim 5, wherein the cylinder head (5) comprises a first valve (12) capable of reversibly opening and closing the first combustion chamber opening (9) of the intake port (7), the first valve (12) having a valve disc (13) and a valve shaft (14) extending along a first valve axis (L12), and the inlet (20) is at least partially arranged within a minimum cylindrical envelope of the valve disc of the first valve (12), which is coaxial with the first valve axis (L12).

7. 6. The cylinder head according to claim 5, wherein the cylinder head (5) comprises a first valve (12) capable of reversibly opening and closing a first combustion chamber inlet opening (9) of the intake port (7), the first valve (12) having a valve disc (13) and a valve shaft (14) extending along a first valve axis (L12); the cylinder head (5) further comprises a second valve (12') capable of reversibly opening and closing a second combustion chamber inlet opening (9') of the intake port (7), the second valve (12') having a valve disc (13') and a valve shaft (14') extending along a second valve axis (L12'); and the injection port (20) is disposed between a first imaginary plane perpendicular to a tube core axis (L19) represented by the first valve axis (L12) and a second imaginary plane parallel to the first imaginary plane on which the second valve axis (L12') is located.

8. 2. A cylinder head according to claim 1, wherein the air guide portions (25, 26, 27) are formed as air guide baffles, and the length (range) of the air guide baffles along the circumference around the tube core axis (L19) is smaller than the length (range) in the radial direction relative to the tube core axis (L19).

9. An internal combustion engine comprising the cylinder head according to claim 1.

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