ARRANGEMENT FOR AN INTERNAL COMBUSTION ENGINE AND METHOD FOR COOLING SUCH AN ARRANGEMENT

Abstract

An arrangement for an internal combustion engine includes a crank case, a cylinder liner disposed in a cylinder of the crank case and including a flange, and a cylinder head disposed on an end of the cylinder delimiting a combustion zone inside the cylinder liner, wherein the flange of the cylinder liner is braced between the cylinder head and the crank case, wherein a flange cooling cavity is provided, which is delimited by a circumferential surface of the flange of the cylinder liner and the cylinder head.

Claims

1. A system, comprising a crank case having a cylinder; a cylinder liner disposed in the cylinder of the crank case, wherein the cylinder liner comprises a flange, and a cylinder head disposed on an end of the cylinder delimiting a combustion zone inside the cylinder liner, wherein the flange of the cylinder liner is braced between the cylinder head and the crank case, wherein a flange cooling cavity is disposed between a circumferential surface of the flange of the cylinder liner and the cylinder head.

2. The system of claim 1, wherein the flange of the cylinder liner is arranged on an end of the cylinder liner closest to the cylinder head.

3. The system of claim 1, wherein the flange cooling cavity is delimited peripherally by the crank case and/or a further component part, separate from the crank case.

4. The system of claim 1, wherein the flange cooling cavity is delimited by a head gasket sealing an interface between the cylinder head and the cylinder liner.

5. The system of claim 1, wherein the flange cooling cavity covers at least 20% of the height of the circumferential surface of the flange of the cylinder liner.

6. The system of claim 1, wherein the flange cooling cavity covers at least 75% of a circumference of the circumferential surface of the flange of the cylinder liner.

7. The system of claim 1, wherein the flange cooling cavity has a substantially polygonal cross-section.

8. The system of claim 1, comprising: a liner cooling cavity disposed between the crank case and a body of the cylinder liner, wherein the liner cooling cavity is disposed further away from the cylinder head than the flange, and a head cooling cavity disposed in the cylinder head, wherein the flange cooling cavity is in fluid communication with the liner cooling cavity through a first set of cooling medium passages, and the flange cooling cavity is in fluid communication with the head cooling cavity through a second set of cooling medium passages.

9. The system of claim 8, wherein the first set of cooling medium passages pass through the crank case.

10. The system of claim 8, wherein the second set of cooling medium passages pass through the cylinder head.

11. The system of claim 8, comprising first openings interfacing the flange cooling cavity and the first set of cooling medium passages and second openings interfacing the flange cooling cavity and the second set of cooling medium passages, wherein, viewed along a longitudinal axis of the cylinder liner, the first openings and the second openings (16) have different angular positions relative to the longitudinal axis.

12. The system of claim 8, wherein the liner cooling cavity is delimited by a wall of the flange of the cylinder liner, and the wall faces away from the cylinder head.

13. The system of claim 1, wherein the body of the cylinder liner has a cylindrical outer surface and/or a cylindrical inner surface.

14. The system of claim 1, comprising an internal combustion engine comprising the crank case, the cylinder liner, and the cylinder head.

15. A method, comprising: flowing a cooling medium through a flange cooling cavity disposed between a circumferential surface of a flange of a cylinder liner and a cylinder head, wherein the cylinder liner is disposed in a cylinder of a crank case, the cylinder head is disposed on an end of the cylinder delimiting a combustion zone inside the cylinder liner, and the flange of the cylinder liner is braced between the cylinder head and the crank case.

16. The method of claim 15, comprising directing the cooling medium to flow at least partially in a circumferential direction around the flange of the cylinder liner.

17. The method of claim 15, wherein the flange cooling cavity covers at least 20% of a height of the circumferential surface of the flange of the cylinder liner, and the flange cooling cavity covers at least 75% of a circumference of the circumferential surface of the flange of the cylinder liner.

18. A system, comprising: a body portion of an internal combustion engine, comprising: a cylinder in the body portion; a flange recess in the body portion, wherein the cylinder is configured to receive a cylinder liner having a flange disposed in the flange recess; and a flange cooling cavity disposed at least partially along the flange recess, wherein the flange cooling cavity is configured to extend at least partially along a circumferential surface of the flange.

19. The system of claim 18, wherein the body portion comprises a liner cooling cavity configured to extend at least partially along the cylinder liner, a head cooling cavity configured to extend at least partially above the cylinder, a first cooling medium passage extending between the flange cooling cavity and the liner cooling cavity, and a second cooling medium passage extending between the flange cooling cavity and the head cooling cavity.

20. The system of claim 19, comprising the internal combustion engine having the cylinder liner disposed in the cylinder.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0072] Further details and advantages are apparent from the figures and the accompanying description of the figures. The figures show:

[0073] FIG. 1 a depiction showing the principle of an embodiment of the invention,

[0074] FIG. 2 a first cross-section of the embodiment of FIG. 1,

[0075] FIG. 3 a second cross-section of the embodiment of FIG. 1,

[0076] FIG. 4 a third cross-section of the embodiment of FIG. 1, and

[0077] FIG. 5 a top view of the embodiment of FIG. 1.

DETAILED DESCRIPTION

[0078] FIG. 1 shows an internal combustion engine 1 comprising the arrangement according to aspects of the invention. The depiction shows two combined cross-sections in order to explain the principle of the arrangement. It should be mentioned that the cooling medium passages of the first set of cooling medium passages 13 and the cooling medium passages of the second set of cooling medium passages 14 actually have an angular separation, which is not shown in FIG. 1, but can be seen in FIG. 5. Proper cross sections through a cooling medium passage of the first set of cooling medium passages 13 and a cooling medium passage of the second set of cooling medium passages 14 are shown in FIGS. 2 and 3, respectively.

[0079] The internal combustion engine 1 comprises the arrangement including the crank case 2, the cylinder liner 3, and the cylinder head 5.

[0080] The cylinder liner 3 is mounted in a simple and easy manufacturable and maintainable manner in a cylinder of the crank case 2 via a flange 4, which is arranged circumferentially around a body 11 of the cylinder liner 3 (top hung cylinder liner 3). For this purpose, the flange 4 is braced between the cylinder head 5 and the crank case 4.

[0081] This bracing can for example be achieved through load screws around the periphery of the cylinder (not depicted).

[0082] The flange 4 in this embodiment has a substantially rectangular cross-section with a chamfer on the outer edge facing the cylinder head.

[0083] Between the flange 4 and the facing surface of the cylinder head 5, there is a head gasket 20 sealing the combustion zone 6.

[0084] The cylinder of the crank case 2 as well as the body 11 of the cylinder liner 3 with its outer surface 18 and its inner surface 19 and the circumferential surface 8 of the flange of the cylinder liner 3 are substantially of a cylindrical shape.

[0085] The flange 4, and consequently the circumferential surface 8 of the flange 4, completely reach around the body 11 of the cylinder liner 3.

[0086] According to aspects of the invention, there is a flange cooling cavity 7 arranged on the circumferential surface 8 of the flange 4.

[0087] The flange cooling cavity 7 is further delimited by the cylinder head 5. For this purpose, the cylinder head 5 has a peripheral surface extending the circumferential surface 8 of the flange 4 in the depiction above the head gasket 20.

[0088] The direction “above” the flange 4 is aligned with a longitudinal axis X (see FIG. 5) of the cylinder liner 3.

[0089] The flange cooling cavity 7 covers slightly more than half of the height of the circumferential surface 8 of the flange 4 and a roughly equal amount of a peripheral surface of the cylinder head 5 (as well as the head gasket 20).

[0090] There is a liner cooling cavity 9 delimited by the outer surface 18 of the cylinder liner 3 on the inside and the crank case 2 on the outside. Therefore, the cylinder liner 3 is in direct contact with the cooling medium during operation of the internal combustion engine 1 (wet cylinder liner 3). As mentioned in the introduction, the advantage of the wet cylinder liner 3 is a higher heat transfer as compared to dry cylinder liners where the cooling cavity is arranged inside the crank case 2.

[0091] The liner cooling cavity 9 is further delimited by a wall 17 of the flange 4, the wall facing away from the cylinder head 5.

[0092] Just like the flange cooling cavity 7, the liner cooling cavity 9 extends all the way around the cylinder liner 3.

[0093] There is also a head cooling cavity 12, which is disposed inside the cylinder head 5 for cooling the same, in particular for cooling the fire plate (in the depiction of FIG. 1 below the head cooling cavity 12) as well as intake and exhaust ports/valves.

[0094] The flange cooling cavity 7, according to aspects of the invention, is tied into the cooling circuit through [0095] a first set of cooling medium passages 13 providing fluid communication between the liner cooling cavity 9 and the flange cooling cavity 7, and [0096] a second set of cooling medium passages 14 providing fluid communication between the flange cooling cavity 7 and the head cooling cavity 12.

[0097] The first set of cooling medium passages 13 and the second set of cooling medium passages 14 can easily be manufactured using bores in the crank case 2 and the cylinder head 5.

[0098] In particular, the first set of cooling medium passages 13 can be manufactured using two bores, each of which meets at a certain point inside the crank case 2.

[0099] Of course, one of these bores originates at a location where the liner cooling cavity 9 is located and a second one of these bores originates where the flange cooling cavity 7 is located.

[0100] First openings 15 interface the first set of cooling medium passages 13 and the flange cooling cavity 7.

[0101] Second openings 16 interface the flange cooling cavity 7 and the second set of cooling medium passages 14.

[0102] It should be mentioned that the outer border of the flange cooling cavity 7 can also be formed by a further component part separate from the crank case 2, if this is desired. Such a separate component part can then of course include (at least part of) the first set of cooling medium passages 13.

[0103] In this embodiment, a pump (not shown) is provided for creating a cooling medium flow from the liner cooling cavity 9 through the flange cooling cavity 7 to the head cooling cavity 12. The cooling medium flow can however also be directed from the head cooling cavity 12 through the flange cooling cavity 7 to the liner cooling cavity 9.

[0104] As mentioned before, the first openings 15 and the second openings 16, and consequently at least partly the first set of cooling medium passages 13 and the second set of cooling medium passages 14, can have an angular separation (see FIG. 5).

[0105] Accordingly, the first openings 15 and the second openings 16 would then not be visible in a single cross-section as depicted in FIG. 1. In this sense, FIG. 1 is only for describing the basic principle of aspects of the invention in this regard. “True” cross-sectional views are depicted in FIGS. 2 to 4, namely [0106] FIG. 2 a cross-sectional view through a cooling passage of the first set of cooling medium passages 13, [0107] FIG. 3 a cross-sectional view through a cooling passage of the second set of cooling medium passages 14, and [0108] FIG. 4 a cross-sectional view, where none of the first set of cooling medium passages 13 or the second set of cooling medium passages 14 are visible.

[0109] FIG. 5 shows a cross-sectional “top view”, i.e., along the longitudinal axis X from the side of the cylinder head 5 and through the cylinder head 5. The longitudinal axis X is perpendicular to the view of FIG. 5 located at the indicated location.

[0110] The longitudinal axis X pertains to the cylinder liner 3. In this embodiment, the longitudinal axis X substantially coincides with the centre axis of the cylinder of the crank case 2.

[0111] The locations of the first set of cooling medium passages 13 are indicated by eight bars. The locations of the second set of cooling medium passages 14 are indicated by eight arrows. The locations of the first openings 15 and the second openings 16 are apparent from these indications.

[0112] Not all of the cooling passages are furnished with reference numerals.

[0113] The first set of cooling medium passages 13 and the second set of cooling medium passages 14 are generally embodied as depicted in FIG. 2 and FIG. 3, respectively.

[0114] Clearly, there is an angular separation, i.e., a non-zero angle with the position of the longitudinal axis X as centre point, between each of the first openings 15 on the one hand and each of the second openings 16 on the other hand.

[0115] This angular separation causes the cooling medium flow through the flange cooling cavity 7 to at least partly have a circumferential direction around the flange 4, which serves to improve the heat transfer in this area.

[0116] FIG. 5 also clearly shows that some of the second set of cooling medium passages 14 are aligned radially with respect to the longitudinal axis X and some are not, in order to optimize the cooling of the cylinder head 5 in the vicinity of intake and exhaust ports (valve seats).

[0117] In this embodiment of the invention, the cooling medium passages of the first set of cooling medium passages 13 are aligned radially with respect to the longitudinal axis X. In other conceivable embodiments of the invention, this does not have to be the case.

[0118] The intake and exhaust ports are the four circular structures roughly in the centre of FIG. 5, the larger ones being the exhaust ports.

[0119] FIG. 5 shows that there are more of the second set of cooling medium passages 14 near the exhaust ports/valves in order to improve the cooling in this area, as the exhaust ports/valves experience higher thermal loads than the intake ports/valves stemming from the exhaust gas after combustion.

[0120] The Figures depict a single cylinder of the internal combustion engine 1. Of course, most internal combustion engines 1 can, and in most cases will, have more than one cylinder. The invention can be realised on all of the cylinders of the internal combustion engine 1 according to aspects of the invention or a subset thereof.