CYLINDER HEAD

Abstract

The invention relates to a cylinder head (1) with at least one recess (23) for arranging at least one gas valve (20) and at least one spark plug (15). The spark plug (15) reaches into a pre-chamber (17) and is arranged along a spark plug rotational axis (16), and the gas valve (20) is arranged along a gas valve rotational axis (19), wherein the gas valve rotational axis (19) is inclined relative to the spark plug rotational axis (16). and the distance (A) between the gas valve rotational axis (19) and the spark plug rotational axis (16) decreases as the distance to the pre-chamber (17) increases in a direction facing away from the combustion chamber (2). The aim of the invention is to provide an improved cylinder head (1) which allows an improved assembly and requires less installation space. According to the invention, this is achieved by the aforementioned cylinder head (1) in that the recess (23) for the spark plug (15) and the gas valve (20) has a surface (0) which is formed by a primary molding process, preferably a casting process, and is post-processed particularly preferably without machining.

Claims

1. Cylinder head comprising: at least one gas valve arranged along a gas valve rotational axis; a pre-chamber; at least one spark plug extending into the pre-chamber and arranged along a spark plug rotational axis; and at least one recess for arranging the at least one gas valve and the at least one spark plug; wherein the gas valve rotational axis is inclined relative to the spark plug rotational axis, and a distance between the gas valve rotational axis and the spark plug rotational axis decreases with a distance from the pre-chamber in a direction facing away from the combustion chamber; characterized in that the at least one recess to the spark plug and gas valve has a surface which is formed by primary shaping process.

2. The cylinder head according to claim 1, wherein an angle of inclination between the gas valve rotational axis and the spark plug rotational axis is between 0.5° and 5°.

3. The cylinder head according to claim 1, wherein the spark plug rotational axis is arranged concentrically to a cylinder rotational axis of a cylinder bore.

4. The cylinder head according to claim 1, wherein a pre-chamber rotational axis is arranged concentrically to a cylinder rotational axis of a cylinder bore.

5. The cylinder head according to claim 1, further including at least one receiving sleeve for the at least one gas valve and the spark plug, in which the at least one recess is formed.

6. The cylinder head according to claim 1, wherein, starting from the recess, a spark plug receiving surface is formed by a mechanically machined surface.

7. The cylinder head according to claim 1, wherein starting from the recess, a gas valve receiving surface is formed by a bore.

8. The cylinder head according to claim 6, wherein the spark plug receiving surface and a gas valve receiving surface are mechanically machined surfaces that are spaced apart and do not intersect.

9. The cylinder head according to claim 8, wherein machining surfaces for obtaining the gas valve receiving surface and the spark plug receiving surface in the recess do not penetrate, so that the machining surfaces do not overlap.

10. The cylinder head according to claim 5, further including gas exchange valves configured and arranged for the exchange of charge into the combustion chamber, wherein each gas exchange valve is assigned a valve spring.

11. The cylinder head according to claim 10, wherein the at least one receiving sleeve extends in the direction of a cylinder rotational axis to a height and/or extends above this height in which the valve springs are arranged, wherein the gas exchange valves are in the closed position.

12. The cylinder head according to claim 10, wherein a distance between at least one receiving sleeve and gas exchange valves in a plane normal to the cylinder rotational axis is small, wherein a ratio between diameter and distance is between 1.5 and 3.5.

13. The cylinder head according to claim 1, wherein an angle of inclination between the gas valve rotational axis and the spark plug rotational axis is 1.5°.

14. The cylinder head according to claim 1, wherein the recess to the spark plug and gas valve has a surface which is formed by casting, and is post-processed without machining.

15. The cylinder head according to claim 1, characterized in that, starting from the recess, a spark plug receiving surface is formed by a bore.

Description

[0023] The invention is further explained with reference to the non-limiting figures, wherein:

[0024] FIG. 1 shows a cylinder head according to the invention in section;

[0025] FIG. 2 shows a receiving sleeve and a pre-chamber sleeve of the cylinder head according to the invention in detail in section analogous to FIG. 1; and

[0026] FIG. 3 shows another detail of the receiving sleeve and pre-chamber sleeve of FIG. 2.

[0027] FIG. 1 shows a cylinder head 1 according to the invention in section. Here, a surface to a combustion chamber 2 of a cylinder not shown in more detail is referred to as a fire deck 3. Gas exchange channels 4 extend into the combustion chamber 2 and can be closed by gas exchange valves 5. For this purpose, the gas exchange valves 5 are each displaceable in a guide 6 and against the force of a valve spring 7.

[0028] In this sectional view, two gas exchange valves 5 are visible, which are arranged on either side of a cylinder rotational axis 8 and are designed as poppet valves. In the embodiment shown, the valve springs 7 are supported away from the combustion chamber 2 in the direction of the cylinder rotational axis 8 on a cover surface 9 of the cylinder head 1 by a first end 10. A second end 11, which is arranged facing away from the combustion chamber 2 around the gas exchange valve 5, is supported against the gas exchange valve 5.

[0029] From the cylinder rotational axis 8 radially inside the two gas exchange valves 5, the cylinder head 1 has a wall 12 with an opening 13, wherein the opening 13 penetrates the cylinder head 1 along the cylinder rotational axis 8. A receiving sleeve 14 is arranged within this opening 13. Within the receiving sleeve 14, a spark plug 15 is arranged along a spark plug rotational axis 16. In the direction of the combustion chamber 2, a pre-chamber 17 is provided adjacent to the spark plug 15, which is at least partially enclosed by a pre-chamber sleeve 18. The pre-chamber 17 is connected to the combustion chamber 2 via overflow openings not shown in greater detail. The pre-chamber 17 has a pre-chamber rotational axis 27 along which it is arranged.

[0030] In the embodiment shown, the pre-chamber 17 with its pre-chamber rotational axis 27 and the spark plug 15 with its spark plug rotational axis 16 are aligned concentrically with a cylinder bore with the cylinder rotational axis 8, which is not shown in more detail.

[0031] In alternative embodiments, this opening 13 is located offset from the cylinder rotational axis 8. In addition, the pre-chamber rotational axis 27 and the spark plug rotational axis 16 can be spaced independently of each other from the cylinder rotational axis 8.

[0032] An outer diameter D of the receiving sleeve 14 reaches very close to the valve springs 7. A distance E between the receiving sleeve 14 and the gas exchange valve 5 corresponds to about 0.4 times the outer diameter D. The relationship between diameter D and distance E is expressed here with the ratio D/E and is about 2.4. In conventional embodiments, a ratio D/E can be between 1.5 and 3.5.

[0033] The distance E is given here in a plane ε which is transverse to the cylinder rotational axis 8 and therefore forms the normal axis to the cylinder rotational axis 8.

[0034] A point of intersection of the gas valve rotational axis 19 and the spark plug rotational axis 16 is arranged outside the receiving sleeve 14, facing away from the combustion chamber 2 in the direction of the cover surface 9.

[0035] Cooling chambers and cooling channels are arranged around the receiving sleeve 14 and the pre-chamber shell 18, which are designated by reference signs K. Cooling chambers K are also provided around the gas exchange channels 4 for cooling the cylinder head 1. Seals are provided to protect the individual operating fluids from each other.

[0036] A gas valve 20 is aligned along a gas valve rotational axis 19. This gas valve 20 extends into a gas channel 21, which in turn fluidically connects the gas valve 20 to the pre-chamber 17.

[0037] The receiving sleeve 14 extends to a height H, from the fire deck 3. At this height, the first end 10 of the valve spring 7 rests on a bearing surface 22. In the embodiment shown, the receiving sleeve 14 extends in the opening 13 almost to the cover surface 9.

[0038] The receiving sleeve 14 and the elements within the receiving sleeve 14, as well as the pre-chamber shell 18, are shown enlarged in FIG. 2. It can be clearly seen here that the gas valve rotational axis 19 is inclined to the spark plug rotational axis 16. The angle of inclination φ is approx. 1.5° in the embodiment shown. In alternative embodiments, the angle of inclination φ is between 0.5° and 5°. In this case, the gas valve 20 is inclined towards the spark plug 15 in the direction of the cover surface 9 of the cylinder head 1.

[0039] Here, the spark plug 15 is arranged concentrically to the cylinder bore with the cylinder rotational axis 8 and the pre-chamber 17.

[0040] The gas valve 20 is particularly small and has a very small distance A to the spark plug 15. Due to the inclination with the angle of inclination φ, the installation space is further reduced. As a result, the distance A to the cover surface 9 of the cylinder head 1 decreases further and further.

[0041] The receiving sleeve 14 has a recess 23 in its interior. This recess 23 is formed for gas valve 20 and spark plug 15 together by casting the receiving sleeve 14. A surface O of the recess 23 is not machined.

[0042] The gas valve 20 and the spark plug 15 both extend into the recess 23 from a combustion chamber 2.

[0043] A gas valve receiving surface 24 is provided for accommodating and securing the gas valve 20 in the receiving sleeve 14. The gas valve receiving surface 24 is formed by machining along a machining surface 25 for the gas valve 20.

[0044] Similarly, a spark plug receiving surface 26 is located in the receiving sleeve 14 for accommodating and securing the spark plug 15. This spark plug receiving surface 26 is in turn formed by machining along a second machining surface 25 for the spark plug 15.

[0045] This gas valve receiving surface 24 and the spark plug receiving surface 26 are cylindrical, for example.

[0046] In the embodiment shown, the spark plug 15 and the gas valve 20 are each disposed in bores.

[0047] Preferably, the pre-chamber sleeve 18 is connected to the receiving sleeve 14 by a connection not shown in detail.

[0048] The machining surfaces 25 for the gas valve 20 and for the spark plug 15 are indicated with dashed lines in FIG. 2 and FIG. 3.

[0049] The machining surfaces 25 do not overlap within the receiving sleeve 14 and are always spaced apart within the receiving sleeve 14.

[0050] FIG. 3 shows another enlarged detail of the receiving sleeve 14 and the pre-chamber sleeve 18 of FIG. 2.