Liquid cooling type cylinder cover

Abstract

The invention relates to a liquid-cooled cylinder head (1) for an internal combustion engine with the top-bottom cooling concept, having a lower cooling chamber (4) adjoining a fire-proof plate (3), and an upper cooling chamber (5) separated from the lower cooling chamber (4) by an intermediate deck (6) and further from the fire-proof plate (3) than the lower cooling chamber (4), the lower cooling chamber (4) and the upper cooling chamber (5) are fluidically connected together in the region of a receiving sleeve (8) arranged centrally with respect to the cylinder (2) for a component (80) which opens centrally into the combustion chamber (7) via at least one annular overflow channel (9) formed by an overflow opening (14) and the receiving sleeve (8) in the intermediate deck (6), the diameter (D) of the substantially circular overflow opening (14) is greater than the outer diameter (d) of the receiving sleeve (8) having an inlet channel arrangement with at least two inlet openings (10E) leading into the combustion chamber (7) and an outlet channel arrangement with at least two outlet openings (10A) leading into the combustion chamber (7). In order to achieve an optimal cooling of the thermally critical region, the invention provides that the overflow opening (14) is arranged eccentrically with respect to the receiving sleeve (8), the central axis (14a) of the overflow opening (14) extending through the center (M) of the overflow opening (14) being spaced apart from the sleeve axis (8a) of the receiving sleeve (8).

Description

Technical Field

[0001] The present invention relates to a liquid-cooled cylinder head for an internal combustion engine with an up-and-down cooling concept, the internal combustion engine in particular having a plurality of cylinders, the cylinder head having a lower cooling chamber and an upper cooling chamber, the lower cooling chamber being adjacent to (the top surface of the combustion chamber), the upper cooling chamber being separated from the lower cooling chamber by an intermediate deck and being much farther from a fireproof plate than the lower cooling chamber, wherein the lower cooling chamber and the upper cooling chamber are flow-connected to each other in the area of ​​a receiving sleeve arranged centrally relative to the cylinder, the receiving sleeve being preferably concentric or parallel to the cylinder axis, for a component which centrally leads into the combustion chamber via at least one annular overflow channel formed by an overflow opening and a receiving sleeve in the intermediate deck, wherein the diameter of the substantially circular overflow opening is greater than the outer diameter of the receiving sleeve, the receiving sleeve having an inlet channel arrangement and an outlet channel arrangement, the inlet channel arrangement having at least two inlet openings leading into the combustion chamber, and the outlet channel arrangement having at least two outlet openings leading into the combustion chamber. Background Art

[0002] The top-bottom cooling concept is a cooling concept in which the coolant first flows through an upper cooling chamber further away from the fire protection plate and only afterwards through a lower cooling chamber closer to the fire protection plate.

[0003] A cylinder head for an internal combustion engine with an upper-lower cooling system is known from WO 2020 / 188071 A1, which has an upper cooling chamber adjacent to the middle deck and a lower cooling chamber adjacent to the fire plate. An annular transfer opening is provided between the upper cooling chamber and the lower cooling chamber in the region of a central receiving sleeve for an injection or ignition device. The transfer opening is concentric with the receiving sleeve.

[0004] DE 103 50 394 A1 describes a cylinder head for a liquid-cooled multi-cylinder internal combustion engine, having a cooling chamber arrangement adjacent to a fire protection plate, which is divided by an intermediate deck into a lower partial cooling chamber and an upper partial cooling chamber. The two partial cooling chambers are flow-connected to one another via an overflow opening in the region of a receiving opening of a sleeve for an intermediate fuel injection device, which is designed as a projection in the receiving opening. Similar cooling arrangements are known from EP 2 998 555 A1, EP 3 333 398 A1 or WO 2012 / 004340 A1. Summary of the invention

[0005] The object of the invention is to achieve optimum cooling of the thermally critical areas of the cylinder head with a simple manufacturing process.

[0006] According to the invention, this is achieved in an internal combustion engine of the type mentioned at the outset in that the overflow opening is arranged eccentrically relative to the receiving sleeve, wherein a center axis of the overflow opening extending through a center point of the overflow opening is spaced apart from a sleeve axis of the receiving sleeve, wherein the center axis of the overflow opening and the sleeve axis are preferably arranged parallel to each other.

[0007] Preferably, the distance between the sleeve axis and the central axis of the overflow opening is smaller than half the outer diameter of the receiving sleeve.

[0008] For optimal cooling, it is advantageous if the center axis of the overflow opening is arranged on the outlet side and / or closer to the outlet valve bridge between the two outlet openings than to the inlet valve bridge between the two inlet openings. In other words, the eccentric overflow opening is oriented in the direction of the outlet valve bridge between the two outlet valves.

[0009] The overflow opening may be formed by casting and / or cutting (machining) the intermediate deck.

[0010] The eccentrically designed overflow opening results in an overflow channel having an eccentric overflow cross section, the cross section on the outlet side being larger than on the inlet side. Thus, improved cooling can be achieved with a low coolant quantity.

[0011] In a variant embodiment of the invention, it is provided that the intermediate deck has at least one local intermediate deck plateau in the region of the overflow opening, which is preferably produced by casting. In this way, the cooling section extends in the direction of the cylinder axis, thereby improving the cooling water flow in the direction of the fire protection plate. In addition, the raised intermediate deck can increase the structural rigidity by connecting the vertical support structure of the cylinder head to the intermediate deck. The vertical support structure connects the oil passage plate (oil passage surface) with the fire protection plate in the cylinder head in the vertical direction. The vertical support structure extends between the valve guide and the overflow opening and / or the inlet opening and the outlet opening and the overflow opening. Similar support structures are known, for example, from AT 522 060B1.

[0012] Advantageously, the intermediate deck plateau is annular and is arranged concentrically around the overflow opening. Advantageously, the intermediate deck plateau can be arranged between the inlet opening or the outlet opening and the overflow opening. The intermediate deck plateau is thus positioned to surround the receiving sleeve between the inlet opening and the outlet opening and the overflow opening in an annular shape and is integrated into the vertical support structure of the cylinder head.

[0013] In order to reduce losses during the flow transfer between the two cooling chambers, it is advantageous if at least one of the intermediate deck plateaus has an inlet chamfer in the region of the upper side facing away from the intermediate deck on the inner side adjacent to the overflow opening.

[0014] In a further embodiment of the invention, provision is made for the overflow opening to have at least one projection, wherein the projection is preferably arranged in the region of the valve bridge. In this case, a projection is to be understood as a cross-sectional widening that deviates outwards from the circular shape of the overflow opening. This makes it possible to increase the flow rate of the coolant passing between the upper cooling chamber and the lower cooling chamber, thereby improving heat dissipation.

[0015] The entire transfer cross section between the upper cooling chamber and the lower cooling chamber for the transfer of coolant results from a combination of machined and cast transfers in the region of the receiving sleeve, namely via the circular eccentric transfer opening and the additional projection. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The invention is explained in more detail below with reference to non-limiting exemplary embodiments shown in the accompanying drawings, in which

[0017] Figure 1 Along Figure 2 A sectional view taken along line II in FIG. 1 shows a cylinder head according to the present invention in a variation of the first embodiment;

[0018] Figure 2 Along Figure 1 A sectional view taken along line II-II in FIG. 1 is used to illustrate the cylinder head; and

[0019] Figure 3 Similar to Figure 2 A cylinder head according to a variation of the second embodiment is shown in a sectional view. DETAILED DESCRIPTION

[0020] Figure 1 and Figure 2 A cylinder head 1 for an internal combustion engine having one or more cylinders 2 is shown. The cylinder head 1 has a lower cooling chamber 4 adjacent to a fireproof plate (combustion chamber top surface) 3 and an upper cooling chamber 5 spaced from the fireproof plate 3, the fireproof plate 3 being separated from the lower cooling chamber 4 by an intermediate deck 6. The terms "bottom" and "top" are used with reference to Figure 1 The illustration shown in FIG. 1 does not refer to the actual installation position of the internal combustion engine during operation. The actual installation position of the cylinder head 1 can therefore deviate from Figure 1 Orientation shown in .

[0021] The upper cooling chamber 5 is located further away from the fire protection plate 3 than the lower cooling chamber 4. The lower cooling chamber 4 and the upper cooling chamber 5 are flow-connected to one another in the region of a receiving sleeve 8, which is arranged centrally relative to the cylinder 2, for example concentrically and parallel to the cylinder axis 2a, for a component 80, such as an injection device or an ignition device, which opens centrally into the combustion chamber 7 via at least one overflow channel 9 in the intermediate deck 6. The cylinder head 1 has two inlet openings 10E, which open into the combustion chamber 7 on the inlet side E of the cylinder head 1 for an inlet channel arrangement (not shown further), and two outlet openings 10A, which open into the combustion chamber 7 on the outlet side A of the cylinder head 1 for an outlet channel arrangement (not shown further).

[0022] An inlet valve bridge 11 is formed between the inlet openings 10E and an outlet valve bridge 12 is formed between the outlet openings 10A. An inlet / outlet valve bridge 13 is located between each inlet 9 and outlet opening 10. The lower cooling chamber 4 has a bridge channel 41, 42, 43 in each case in the region of the inlet valve bridge 11, in the region of the outlet bridge 12 and in the region of the inlet / outlet valve bridge 13. The bridge channels 41, 42, 43 are arranged in Figure 2 Indicated by dotted line.

[0023] The overflow channel 9 between the upper cooling chamber 5 and the lower cooling chamber 4 is oriented substantially in the direction of the cylinder axis 2a. It is formed by a substantially circular overflow opening 14 arranged in the intermediate deck 6 and, for example, a cylindrical outer surface 8b of the receiving sleeve 8. The overflow opening 14 can be molded by casting into the cylinder head 1 and / or formed by machining the intermediate deck 6.

[0024] The overflow opening 14 of the overflow channel 9 is arranged eccentrically relative to the sleeve axis 8a of the receiving sleeve 8. The overflow channel 9 has a substantially annular eccentric cross section. The diameter D of the overflow opening 14 is greater than the outer diameter d of the receiving sleeve 8. The central axis 14a of the overflow opening 14 extending through the center M of the circular overflow opening 14 is spaced apart from the sleeve axis 8a of the receiving sleeve 8. The central axis 14a of the overflow opening 14 and the sleeve axis 8a are arranged, for example, substantially parallel to each other. The central axis 14a of the overflow opening 14 is arranged on the outlet side A. In other words, the central axis 14a is arranged to be closer to the outlet valve bridge 12 between the two outlet openings 10A than the inlet valve bridge 11 between the two inlet openings 10E. The distance a between the sleeve axis 8a and the central axis 14a is less than half of the outer diameter d of the receiving sleeve 8, in particular less than a quarter of the outer diameter d of the receiving sleeve 8. The eccentrically arranged overflow opening 14 results in an eccentrically shaped overflow channel 9, which has a larger cross section on the outlet side A than on the inlet side E (see Figure 2 ).

[0025] Furthermore, at least one intermediate deck plateau section 16 , produced, for example, by casting, may be arranged between the inlet opening 10E and / or the outlet opening 10A and the overflow opening 14 . Figure 1 and Figure 2 1 shows an embodiment in which an intermediate deck high platform portion 16 arranged in an annular shape and concentrically surrounding the overflow opening 14 and the receiving sleeve 8 is provided between the outlet opening 10A or the inlet opening 10E and the overflow opening 14. The position of the intermediate deck high platform portion 16 is Figure 2 The middle deck high platform 16 connects the vertical support structure 18 of the cylinder head 1 to the middle deck 6. This allows the structural rigidity of the cylinder head 1 to be increased. The vertical support structure 18 connects the oil plate 19 to the fireproof plate 4 in the cylinder head 1 in the vertical direction and extends between the valve (valve) guide and / or the inlet opening 10E and the outlet opening 10A and the overflow opening 14.

[0026] like Figure 1 It can be seen that in this exemplary embodiment, the middle deck platform 16 has an inlet chamfer 17 on the inner side adjacent to the overflow opening 14 in the area facing away from the upper side of the middle deck 6, thereby minimizing flow losses between the upper cooling chamber 5 and the lower cooling chamber 4 during flow transfer.

[0027] The mid-deck raised portion 16 extends the cooling distance in the direction of the cylinder axis 2a and improves the cooling water flow in the direction of the fireproof plate 4. Furthermore, the raised mid-deck 16 increases the structural rigidity.

[0028] The overflow opening 14 may have at least one protrusion 15 in the region of the valve bridge, for example the outlet valve bridge 12, in order to increase the flow rate of the coolant passing between the upper cooling chamber 5 and the lower cooling chamber 4 and thus improve heat dissipation. Figure 3 The middle deck platform and vertical support structure are shown in Figure 3 Not shown.

[0029] The cylinder head 1 has a so-called top-bottom cooling concept. The top-bottom cooling concept is a cooling concept in which the coolant first flows through the upper cooling chamber 5 further away from the fire protection plate and only thereafter through the lower cooling chamber 4 close to the fire protection plate.

[0030] The coolant flows radially in the cylinder head 2 in the direction of the receiving sleeve 8 according to the arrow P in the upper cooling chamber 5 and reaches the lower cooling chamber 4 via the eccentrically designed overflow channel 9. The receiving sleeve 8 and the component 80 received by the receiving sleeve 8 are cooled in the process. The coolant flows radially outwards through the bridge channels 41, 42, 43 of the lower cooling chamber 4, wherein the outlet valve bridge 12 as well as the thermally critical areas of the inlet valve bridge 11 and the inlet / outlet valve bridge 13 are cooled ( Figure 1 Due to the eccentric shape of the overflow channel 9 , significantly more coolant flows through the overflow channel 9 on the outlet side A from the upper cooling chamber 5 into the lower cooling chamber 4 than on the inlet side E.

Claims

1. A liquid-cooled cylinder head (1) for an internal combustion engine with an upper-lower cooling concept, the internal combustion engine in particular having a plurality of cylinders (2), the cylinder head (1) having a lower cooling chamber (4) and an upper cooling chamber (5), the lower cooling chamber (4) being adjacent to a fire protection plate (3), the upper cooling chamber (5) being separated from the lower cooling chamber (4) by an intermediate deck (6) and being much further away from the fire protection plate (3) than the lower cooling chamber (4), wherein: The lower cooling chamber (4) and the upper cooling chamber (5) are flow-connected to each other in the region of the receiving sleeve (8) arranged centrally relative to the cylinder (2), the receiving sleeve (8) preferably being concentric or parallel to the cylinder axis (2a), the receiving sleeve being used for a component (8) which opens centrally into the combustion chamber (7) via at least one annular overflow channel (9) in the intermediate deck (6) formed by the overflow opening (14) and the receiving sleeve (8), wherein the diameter (D) of the substantially circular overflow opening (14) is greater than the outer diameter (d) of the receiving sleeve (8), the receiving sleeve having an inlet channel arrangement and An outlet channel arrangement, wherein the inlet channel arrangement has at least two inlet openings (10E) leading to the combustion chamber (7), and the outlet channel arrangement has at least two outlet openings (10A) leading to the combustion chamber (7), characterized in that the overflow opening (14) is arranged eccentrically relative to the receiving sleeve (8), wherein a center axis (14a) of the overflow opening (14) extending through a center point (M) of the overflow opening (14) is spaced apart from a sleeve axis (8a) of the receiving sleeve (8), wherein the center axis (14a) of the overflow opening (14) and the sleeve axis (8a) are preferably arranged parallel to each other.

2. The cylinder head (1) according to claim 1, characterized in that The distance (a) between the sleeve axis (8a) and the central axis (14a) of the overflow opening (14) is less than half of the outer diameter (d) of the receiving sleeve (8), preferably less than one quarter of the outer diameter (d) of the receiving sleeve (8).

3. The cylinder head (1) according to claim 1 or 2, characterized in that: The overflow opening (14) of the overflow channel (9) is formed by cutting the intermediate deck (6).

4. The cylinder head (1) according to any one of claims 1 to 3, characterized in that The intermediate deck (6) has at least one intermediate deck plateau (16) in the region of the overflow opening (14).

5. The cylinder head (1) according to claim 4, characterized in that The intermediate deck plateau (16), which is preferably produced by casting, is arranged between the inlet opening (10E), the outlet opening (10A) and the overflow opening (14).

6. The cylinder head (1) according to claim 4 or 5, characterized in that The intermediate deck plateau portion is annular and is concentrically arranged around the overflow opening (14).

7. The cylinder head (1) according to any one of claims 4 to 6, characterized in that The intermediate deck plateau (16) has an inlet chamfer (17) on the inner side adjacent to the overflow opening (14) in a region facing away from the upper side of the intermediate deck (6).

8. The cylinder head (1) according to any one of claims 4 to 7, characterized in that The mid-deck plateau (16) connects the vertical support structure (18) of the cylinder head (1) to the mid-deck (6).

9. The cylinder head (1) according to any one of claims 1 to 8, characterized in that The central axis (14a) of the overflow opening (14) is arranged on the outlet side (A) and / or is arranged closer to the outlet valve bridge (12) between the two outlet openings (10A) than to the inlet valve bridge (11) between the two inlet openings (10E).

10. The cylinder head (1) according to any one of claims 1 to 9, characterized in that The transfer opening (14) has at least one projection (15), wherein the projection (15) is preferably arranged in the region of the exhaust valve bridge (12).

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