EP3938631A1

EP3938631A1 - Cylinder block design for providing improved cooling performance of liners

Info

Publication number: EP3938631A1
Application number: EP20801858.0A
Authority: EP
Inventors: Chang C. Liu; Nathaniel P. Hassall
Original assignee: Cummins Inc
Current assignee: Cummins Inc
Priority date: 2019-05-08
Filing date: 2020-04-09
Publication date: 2022-01-19
Also published as: CN111911309B; CN111911309A; WO2020226839A1; EP3938631A4

Abstract

Systems and methods are provided to deliver coolant around a cylinder liner. The systems and methods uses a water-jacket. The water-jacket includes an inlet placed at a bottom of the water-jacket. The inlet has a smooth guidance pathway to deliver coolant smoothly into the water-jacket. The water-jacket also includes three outlets placed at a top of the water-jacket.

Description

CYLINDER BLOCK DESIGN FOR PROVIDING IMPROVED COOLING

PERFORMANCE OF LINERS

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to and the benefit of Chinese Patent Application No. 201910378607.6, filed May 8, 2019, the contents of which are herein incorporated by reference.

TECHNICAL FIELD

[0002] The present invention relates to a cooling system for liners of an internal combustion engine and methods for manufacturing such cooling system.

BACKGROUND

[0003] Cooling of internal combustion engines is required because of the high temperatures generated within the engine, particularly in the area of an engine's combustion chamber, which includes the cylinder liner and the cylinder head. While cooling is a required function of internal combustion engines, evaporation of coolant can cause cavitation corrosion/erosion in certain areas of the cylinder liner. Therefore, the developing of systems for the cooling of cylinder liners, particularly at a ring reversal location, has been challenging.

SUMMARY

[0004] One embodiment relates to a cooling system for cooling a cylinder liner. The cooling system includes a water-jacket. The water-jacket includes an inlet placed at a bottom of the water-jacket. The inlet has a smooth guidance pathway to deliver coolant smoothly into the water-jacket. The water-jacket also includes three outlets placed at a top of the water-jacket.

[0005] Another embodiment relates to an engine system. The engine system includes a water- jacket. The water-jacket includes an inlet placed at a bottom of the water-jacket. The inlet has a smooth guidance pathway to deliver coolant smoothly into the water-jacket. The water-jacket also includes three outlets placed at a top of the water-jacket.

[0006] Still another embodiment relates to a method of manufacturing a water-jacket. The method includes: forming an inlet at a bottom of the water-jacket; forming a smooth guidance pathway within the inlet for delivering coolant smoothly into the water-jacket; and forming three outlets at a top of the water-jacket.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007] FIG. l is a diagram of an engine system at a perspective view according to an example embodiment.

[0008] FIG. 2 is a diagram of the engine system of FIG. 1 at another perspective view.

[0009] FIG. 3 is a diagram of a water-jacket, according to an example embodiment.

[0010] FIG. 4 is a diagram of a water-jacket for a cooling system of an internal combustion engine, according to an example embodiment.

[0011] FIG. 5 is a flowchart of a process of manufacturing a water-jacket for a cylinder liner, according to an example embodiment.

DETAILED DESCRIPTION OF EMBODIMENTS

[0012] Referring to FIG. 1, a diagram of an engine system 100 is shown at a perspective view according to an example embodiment. The engine system 100 may include any suitable internal combustion engines (e.g., four-cylinder engines, six-cylinder engines, etc.). The engine system 100 includes an engine block 101. The engine block 101 includes multiple cylinder openings (e.g., cylinder opening 103a, 103b, 103c, 103d, 103e, 103f). Each cylinder opening is designed for hosting a cylinder. Each cylinder has a cylinder liner formed a cylindrical hollow body for hosting a piston of the cylinder. The piston can travel reciprocally within the cylinder liner. In some embodiments, each cylinder liner has a mid-stop formed in a side wall of the cylinder liner. The mid-stop is formed at a depth from a top surface of the engine block 101 above a top surface of the piston when the piston reaches a top-dead-center position (e.g., at the top of the piston stroke).

[0013] The engine block 101 includes multiple water-jackets (e.g., water-jackets 105a, 105b, 105c, 105d, 105e, 105f) for delivering coolant around an outer surface of the cylinder liners. The water-jackets can be used for delivering any suitable coolant (e.g., water, oil, etc.) within the engine system 100. Each water-jacket is formed with thin walls surrounding a corresponding cylinder liner. The thin wall design lowers and uniforms the thermal distortion of the cylinder liner. Each water-jacket (e.g., 105a) has an inlet (e.g., inlet 107) and three outlets (e.g., outlets 109, 111, 113).

[0014] The inlet is placed at a corner which is located at an exhaust side 115 (e.g., where an exhaust manifold is located) and a front side 121 of the engine block 101. The inlet (e.g., inlet 107) is designed with a unique geometry, which has a smooth guidance pathway (e.g., smooth walls without sharp turns) towards the outer surface of the cylinder liner. This design allows coolant to flow smoothly into the water jacket and towards the outer surface of the cylinder liner. The inlet is placed at the bottom of the water-jacket in order to provide uniform mass flow around the cylinder liner.

[0015] The three outlets are placed at a top surface of the cylinder block 101. Each outlet is connected with an accumulator feature inside of the water-jacket. A first outlet (e.g., outlet 111) is placed at a corner which is located at the exhaust side 115 and a rear side 119 of the engine block 101. A second outlet (e.g., outlet 109) is placed at a corner which is located at an intake side 117 and the front side 121 of the engine block 101. A third outlet (e.g., outlet 113) is placed at a corner which is located at the intake side 117 and the rear side 119 of the engine block 101.

[0016] Referring to FIG. 2, a diagram of the engine system 100 of FIG. 1 is shown at another perspective view. The three outlets are placed at a top surface of the water-jacket. Each outlet (e.g., outlet 111) includes an outlet hole connected to an accumulator (e.g., accumulator 123) within the water-jacket. The accumulator is designed to accumulate coolant and deliver the accumulated coolant to the outlet hole. The accumulator has a smooth guidance pathway towards the outer surface of the cylinder liner.

[0017] Referring to FIG. 3, a diagram of a water-jacket 300 is shown according to an example embodiment. The water-jacket 300 is designed similar as the water-jackets described in FIG. 1 and FIG. 2. The water-jacket 300 includes an inlet 301, as well as a first outlet 303, a second outlet 305, and a third outlet 307. As described above, the water-jacket 300 is used within a cylinder block and is located at a direction defined by an exhaust side, an intake side, a front side, and a rear side of the cylinder block. The direction is defined for illustration purposes.

[0018] The inlet 301 is located at a corner that is formed by the exhaust side and the front side. The inlet 301 is located at the bottom of the water-jacket 300. The inlet 301 is designed with smooth guidance pathway to deliver uniform flow to the water-jacket 300. The inlet 301 has a dimension larger than the outlets.

[0019] The first outlet 303 is placed at a comer that is formed by the exhaust side and the rear side of the water-jacket 300. The first outlet 303 is located at the top of the water-jacket 300.

The first outlet 303 is connected to a first outlet accumulator 309. The first outlet accumulator 309 is formed from the bottom of the water-jacket 300 to the top of the water-jacket 300. The first outlet accumulator 309 is connected between the first outlet 303 and a first coolant path 317. The first outlet accumulator 309 is designed to collect a portion of coolant delivered in the first coolant path 317 and directs the portion of the coolant out of the water-jacket 300 through the first outlet 303. The first outlet accumulator 309 has smooth guidance pathway (e.g., smooth flow path, smooth walls) to connect to the first coolant path 317.

[0020] The second outlet 305 is placed at a corner that is formed by the intake side and the rear side of the water-jacket 300. The second outlet 305 is located at the top of the water-jacket 300. The second outlet 305 is connected to a second outlet accumulator 311. The second outlet accumulator 311 is formed from the bottom of the water-jacket 300 to the top of the water-jacket 300. The second outlet accumulator 311 is connected between the second outlet 305 and a second coolant path 319. The second outlet accumulator 311 is also connected between the second outlet 305 and a third coolant path 321. The second outlet accumulator 311 is designed to collect a portion of coolant delivered in the second coolant path 319 and a portion of coolant delivered in the third coolant path 321, and directs the collected coolant out of the water-jacket 300 through the second outlet 305. The second outlet accumulator 311 has smooth guidance pathway (e.g., smooth flow path, smooth walls) to connect to the second coolant path 319 and to the third coolant path 321.

[0021] The third outlet 307 is placed at a corner that is formed by the intake side and the front side of the water-jacket 300. The third outlet 307 is located at the top of the water-jacket 300. The third outlet 307 is connected to a third outlet accumulator 313. The third outlet accumulator 313 is formed from the bottom of the water-jacket 300 to the top of the water-jacket 300. The third outlet accumulator 313 is connected between the third outlet 307 and a fourth coolant path 323. The accumulator 313 is designed to collect a portion of coolant delivered in the fourth coolant path 323 and directs the portion of the coolant out of the water-jacket 300 through the third outlet 307. The third outlet accumulator 313 has a smooth guidance pathway (e.g., smooth flow path, smooth walls) to connect to the fourth coolant path 323.

[0022] Coolant flows smoothly into the water-jacket 300 through the inlet 301. The coolant flows into the first coolant path 317 located at the exhaust side and into the fourth coolant path 323 located at the front side. A portion of the coolant in the first coolant path 317 flows to the first outlet accumulator 309. The rest of the coolant in the path 317 flows into the second coolant path 319 located at the rear side. A portion of the coolant in the fourth coolant path 323 flows into the accumulator 313. The rest of the coolant in the fourth coolant path 323 flows into the third coolant path 321 located at the intake side of the water-jacket 300. The coolant in the second coolant path 319 and the coolant in the third coolant path 321 flows into the accumulator 311 and further flows out of the water-jacket through the second outlet 305. Each of the coolant paths 317, 319, 321, 323 is designed with a thin thickness in order to provide uniform flow. [0023] Referring to FIG. 4, a diagram of a water-jacket 400 for a cooling system of an internal combustion engine is shown according to an example embodiment. The water-jacket 400 can be similar as the water-jackets described in the FIGS. 1-3.

[0024] The water-jacket 400 includes an inlet 401 and a coolant path 403. The inlet 401 is designed with a smooth guidance pathway that does not include sharp turns or curves along the wall of the inlet 401. The smooth guidance pathway includes a smooth wall surface along the inner wall surface of the inlet 401. In this way, the smooth inner wall surface (e.g., no rough surfaces such as bumps, pots, curves, or sharp turns) provides minimum flow resistance. The inlet 401 is fluidly connected to the coolant path 403. The connecting point 405 between the inlet 401 and the coolant path 403 is designed with a maximum turning angle so that the connecting point 405 does not define“sharp” turns that can generate turbulence and change flow speed. This design allows coolant delivered into the water-jacket smoothly and forms uniform flow within the coolant path 403. The coolant path 403 is formed with a thin thickness path along an outer surface of a cylinder liner. The coolant path 403 includes coolant paths similar to the coolant paths 317, 319, 321, and 323 of FIG. 3.

[0025] FIG. 5 is a flowchart of a process 500 of manufacturing a water-jacket for a cylinder liner according to an example embodiment. At 501, a circular path with thin walls is formed for delivering coolant around the cylinder liner. An inner surface of the circular path is formed to be adjacent to an outer surface of the cylinder liner in order to cooling the cylinder liner efficiently.

[0026] At 503, an inlet is formed at a first corner of the water-jacket to inject coolant into the circular path of the water-jacket. The inlet is formed at the bottom of the water-jacket. The inlet is formed with a smooth path and smooth connection to the circular path in order to smoothly deliver coolant into the water-jacket.

[0027] At 505, three accumulators are formed at three comers (e.g., second, third, and fourth corners) of the water-jacket. Each of the accumulators is formed to be smoothly connected to the circular path in order to receive coolant from the circular path smoothly. The accumulators are formed from the bottom of the water-jacket to a top surface of the water-jacket. [0028] At 507, three outlets are formed. Each outlet is formed to connect to an accumulator at a corresponding comer of the water-jacket. Each outlet is formed at a top surface of the water- jacket to deliver coolant out of the water-jacket.

[0029] While this specification contains many specific implementation details, these should not be construed as limitations on the scope of what may be claimed, but rather as descriptions of features specific to particular implementations. Certain features described in this specification in the context of separate implementations can also be implemented in combination in a single implementation. Conversely, various features described in the context of a single

implementation can also be implemented in multiple implementations separately or in any suitable sub combination. Moreover, although features may be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a subcombination or variation of a subcombination.

[0030] It is important to note that the construction and arrangement of the system shown in the various exemplary implementations is illustrative only and not restrictive in character. All changes and modifications that come within the spirit and/or scope of the described

implementations are desired to be protected. It should be understood that some features may not be necessary and implementations lacking the various features may be contemplated as within the scope of the application, the scope being defined by the claims that follow. It should be understood that features described in one embodiment could also be incorporated and/or combined with features from another embodiment in manner understood by those of ordinary skill in the art.

Claims

WHAT IS CLAIMED IS:

1. A cooling system for cooling a cylinder liner, comprising:

a water-jacket comprising:

an inlet placed at a bottom of the water-jacket, the inlet placed at a first corner that is located at an exhaust side and a front side of the cooling system, the inlet having a smooth guidance pathway to deliver coolant smoothly into the water-jacket; and

three outlets placed at a top of the water-jacket, a first outlet of the three outlets placed at a second corner that is located at the exhaust side and a rear side of the cooling system, a second outlet of the three outlets placed at a third comer that is located at the rear side and an intake side of the cooling system, a third outlet of the three outlets placed at a fourth corner that is located at the intake side and the front side of the cooling system.

2. The cooling system of claim 1, wherein the smooth guidance pathway is provided by a smooth surface at the inner wall of the inlet and a smooth turning point within the inlet .

3. The cooling system of claim 1 or 2, wherein the water-jacket further comprises a first coolant path, a second coolant path, a third coolant path, and a fourth coolant path.

4. The cooling system of claim 3, wherein the first coolant path is connected between the inlet and the first outlet of the three outlets and connected to the second coolant path, the first coolant path directing coolant from the inlet to the first outlet.

5. The cooling system of claim 4, wherein the second coolant path is connected between the first outlet and the second outlet of the three outlets and connected to the third coolant path, the second coolant path directing coolant from the first coolant path to the second outlet.

6. The cooling system of claim 5, wherein the third coolant path is connected between the second outlet and the third outlet of the three outlets and connected to the fourth coolant path, the third coolant path directing coolant from the fourth coolant path to the second outlet.

7. The cooling system of claim 6, wherein the fourth coolant path is connected between the third outlet and the inlet, the fourth coolant path directing coolant from the inlet to the third outlet.

8. The cooling system of any of claims 1-2 and 4-7, wherein the water-jacket further comprises three accumulators, each accumulator connected to an outlet.

9. An engine system, comprising:

a cylinder block comprising a plurality of liners for hosting a plurality of cylinders;

a plurality of water-jackets, each water-jacket disposed adjacent to an outer surface of a corresponding liner, each water-jacket comprising:

an inlet placed at a bottom of the water-jacket, the inlet having a smooth guidance pathway to deliver coolant smoothly into the water-jacket; and

three outlets placed at a top of the water-jacket.

10. The engine system of claim 9, wherein the inlet is placed at a first corner that is located at an exhaust side and a front side of a cooling system of the engine system.

11. The engine system of claim 9 or 10, wherein the water-jacket further comprises a first coolant path, a second coolant path, a third coolant path, and a fourth coolant path.

12. The engine system of claim 11, wherein the first coolant path is connected between the inlet and a first outlet of the three outlets and connected to the second coolant path, the first coolant path directing coolant from the inlet to the first outlet.

13. The engine system of claim 12, wherein the second coolant path is connected between the first outlet and a second outlet of the three outlets and connected to the third coolant path, the second coolant path directing coolant from the first coolant path to the second outlet.

14. The engine system of claim 13, wherein the third coolant path is connected between the second outlet and a third outlet of the three outlets and connected to the fourth coolant path, the third coolant path directing coolant from the fourth coolant path to the second outlet.

15. The engine system of claim 14, wherein the fourth coolant path is connected between the third outlet and the inlet, the fourth coolant path directing coolant from the inlet to the third outlet.

16. The engine system of any of claims 9-10 and 12-15, wherein the water-jacket further comprises three accumulators, each accumulator connected to an outlet.

17. A method of manufacturing a water-jacket, comprising: forming a water-jacket body;

forming an inlet at a bottom of the water-jacket body;

forming a smooth guidance pathway within the inlet for delivering coolant smoothly into the water-jacket body; and

forming three outlets at a top of the water-jacket body.

18. The method of claim 17, wherein the inlet is formed at a first corner that is located at an exhaust side and a front side of a cooling system.

19. The method of claim 17 or 18, further comprising forming a circular coolant path that is connected between the inlet and the three outlets.

20. The method of claim 17 or 18, further comprising forming an accumulator to connect to each of the three outlet for accumulating coolant and delivering coolant into a corresponding outlet.