Internal combustion engine with top-down cooling

Abstract

An internal combustion engine having an engine block and one or more cylinder heads. The engine block houses a plurality of cylinder liners and includes a cylinder liner cooling jacket below an upper planar surface of the engine block and in fluid communication with the plurality of cylinder liners. One or more cylinder heads are attached to the upper planar surface of the engine block, and each of the one or more cylinder heads includes one or more cylinder head cooling jackets and one or more downward coolant passages extending from the one or more cylinder head cooling jackets to the cylinder liner cooling jackets for conveying coolant from the one or more cylinder head cooling jackets to the cylinder liner cooling jackets.

Description

Technical Field

[0001] The present invention relates generally to an internal combustion engine and, more particularly, to an internal combustion engine with top-down cooling. Background Art

[0002] Internal combustion engines are typically liquid-cooled. Conventional cooling systems for internal combustion engines may include a coolant pump that pumps coolant into a cooling jacket of the engine's engine block. The coolant then flows longitudinally through a portion of the cooling jacket surrounding the engine's cylinders. The cylinders are cooled by contacting the passing coolant with the cylinder walls. The coolant then flows upward into the water jacket of one or more cylinder heads to cool components of the cylinder heads, such as injectors and valves, before exiting the engine. The coolant system may also include multiple other components, such as a radiator, thermostat, EGR cooler, aftercooler, and oil cooler.

[0003] As mentioned above, conventional coolant flow paths through an engine can result in uneven cylinder cooling because the coolant flows longitudinally along the cylinders, and the coolant flow is uneven across the cylinders, leading to increased cylinder temperatures. U.S. Patent No. 7,225,766 (the "'766 patent"), issued to Zahdeh on June 5, 2007, discloses a coolant jacket design for an engine in which coolant is delivered to the upper ends of the cylinders, adjacent to the combustion chambers, via inlet passages. The coolant is evenly distributed along the cylinders into side flow slots and flows axially down the cylinders to the lower end of the cooler, where it is collected in outlet passages and discharged from the coolant jacket. Summary of the Invention

[0004] According to one aspect of the present invention, an internal combustion engine includes an engine block and one or more cylinder heads. The engine block houses a plurality of cylinder liners and includes a cylinder liner cooling jacket below an upper planar surface of the engine block and in fluid communication with the plurality of cylinder liners. One or more cylinder heads are attached to the upper planar surface of the engine block, and each of the one or more cylinder heads includes one or more cylinder head cooling jackets and one or more downward coolant passages extending from the one or more cylinder head cooling jackets to the cylinder liner cooling jackets for conveying coolant from the one or more cylinder head cooling jackets to the cylinder liner cooling jackets.

[0005] According to another aspect of the present invention, a method of cooling an internal combustion engine includes an engine block and one or more cylinder heads attached to an upper planar surface of the engine block. The method includes pumping coolant into the one or more cylinder heads and directing the coolant from the one or more cylinder heads downwardly into the engine block adjacent to another of a plurality of cylinder liners housed in the engine block to cool the cylinder liners.

[0006] According to another aspect of the present invention, an engine block includes an upper planar surface, a plurality of inline cylinders extending downwardly from the upper planar surface into the engine block, a cylinder cooling jacket positioned below the upper planar surface and surrounding the plurality of cylinders, a coolant cavity positioned below the cylinder cooling jacket, a plurality of upward coolant passages extending from the coolant cavity through the upper planar surface and away from the cylinder cooling jacket, and a plurality of downward coolant passages extending from the upper planar surface into the cylinder cooling jacket to supply coolant to the cylinder cooling jacket. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Further features and advantages will become apparent from the following illustrative embodiments which will now be described by way of example only and not limited to the scope of the claims and with reference to the accompanying drawings, in which:

[0008] Figure 1 is a schematic diagram of a side view of an exemplary embodiment of an engine having internal coolant passages;

[0009] Figure 2 yes Figure 1 a schematic diagram of an end view of an engine;

[0010] Figure 3 yes Figure 1 A partial side cross-sectional view of an inlet coolant rail and an inlet coolant rail of an engine;

[0011] Figure 4 yes Figure 1 A partial top view of the platform surface of the engine;

[0012] Figure 5 yes Figure 1 A partial side cross-sectional view of an upper cooling jacket and a lower cooling jacket of an engine; and

[0013] Figure 6 yes Figure 1 A partial perspective view of the upper and lower cooling jackets of an engine. DETAILED DESCRIPTION

[0014] Although the present invention describes certain embodiments of an internal combustion engine with internal coolant passages, the present invention should be considered exemplary and is not intended to be limited to the disclosed embodiments. In addition, certain elements or features of the embodiments disclosed herein are not limited to specific embodiments, but are applicable to all embodiments of the present invention.

[0015] Reference Figure 1-2 An exemplary embodiment of an internal combustion engine 10, such as a diesel engine, is shown. Engine 10 can provide power to various types of applications and / or machines. For example, engine 10 can power machines such as off-road trucks, railroad locomotives, earth-moving machines such as wheel loaders, excavators, dump trucks, backhoes, motor graders, material handlers, and the like. The term "machine" can also refer to stationary equipment, such as a generator driven by engine 10 to generate electricity.

[0016] The engine 10 includes an engine block 12 housing one or more cylinder liners 14 defining one or more corresponding cylinders 16 (see FIG. Figure 6 ). Each cylinder 16 may be configured to slidably receive a piston (not shown) therein. In the illustrated embodiment, engine 10 is in-line and includes six cylinders 16. However, in other embodiments, engine 10 may include more or less than six cylinders 16 and may be V-type, rotary, or other types known in the art.

[0017] The engine block 12 extends along a longitudinal axis X and includes a first end 18, a second end 20 opposite the first end 18, a first side 22 extending between the first end 18 and the second end 20, and a second side 24 opposite the first side 22 and extending between the first end 18 and the second end 20. The engine block 12 also includes a lower portion 26 and an upper portion 28 opposite the lower portion 26. The upper portion 28 defines a planar upper surface or deck 30.

[0018] like Figure 5 As shown, one or more cylinder heads 32 are attached to the platform 30. The one or more cylinder heads 32 include a top end 33 and a bottom end 35. When the one or more cylinder heads 32 are attached to the engine block 12, the bottom end 35 of each of the one or more cylinder heads 32 faces the platform 30, typically with a gasket (not shown) therebetween. To attach the one or more cylinder heads 32 to the engine block 12, the platform 30 may include a plurality of bolt holes 31 ( Figure 4 The one or more cylinder heads 32 include a plurality of ports 34 with a valve 36 associated with each port 34. The valves 36 are configured to regulate fluid communication into and out of the one or more cylinders 16 via the ports 34.

[0019] The engine 10 is liquid-cooled and includes a plurality of passages in the engine block 12 and one or more cylinder heads 32 for flowing coolant therethrough to cool the engine 10. The engine 10 includes a coolant pump 40 for pumping coolant through the engine 10. Any suitable coolant pump 40 capable of providing the desired coolant flow through the engine 10 may be used.

[0020] Engine 10 may include an oil cooler 42 ( Figure 1 ), which receives coolant from a coolant pump 40 to cool the oil in the engine 10. Any suitable oil cooler 42 may be used, such as a shell and tube or plate heat exchanger. In the illustrated embodiment, the engine block 12 includes an oil cooler cavity 44 configured to accommodate the oil cooler 42. In the illustrated embodiment, the oil cooler cavity 44 is located in or near the lower portion 26 of the engine block 12 and adjacent the first end 18 of the engine block 12.

[0021] The engine 10 includes a first coolant cavity 46, referred to as an inlet coolant rail, adjacent to and in fluid communication with the oil cooler cavity 44. The first coolant cavity 46 can be configured in any suitable manner, such as various shapes, sizes, and locations within the engine block 12. In the illustrated embodiment, the first coolant cavity 46 extends parallel to the longitudinal axis X from the oil cooler cavity 44 to a location adjacent to or near the second end 20 of the engine block 12. Figure 2 As shown, the first coolant cavity 46 extends along the first side 22 of the engine block 12 adjacent a crankcase 48 of the engine 10 .

[0022] The engine 10 includes a second coolant cavity 50, referred to as an inlet coolant rail, that is in fluid communication with the first coolant cavity 46. The second coolant cavity 50 can be configured in any suitable manner, such as various shapes, sizes, and locations in the engine block 12. In the illustrated embodiment, the second coolant cavity 50 extends parallel to and above the first coolant cavity 46 and can extend from the first end 18 to the second end 20 of the engine block 12. The second coolant cavity 50 is separated from the first coolant cavity 46 by a longitudinally extending first wall 52. One or more first coolant passages 54 fluidly connect the second coolant cavity 50 to the first coolant cavity 46. In the illustrated embodiment, the first wall 52 is not present at or near the second end 20 of the engine block 12, such that the first coolant cavity 46 opens into the second coolant cavity 50 to form the first coolant passage 54. However, the one or more first coolant passages 54 can be formed in any suitable manner to place the second coolant cavity 50 in fluid communication with the first coolant cavity 46. As Figure 2 As shown, the second coolant cavity 50 extends along the first side 22 of the engine block 12 adjacent the crankcase 48 of the engine 10 .

[0023] The engine 10 includes one or more second coolant passages 56 extending from the second coolant cavity 50 to the one or more cylinder heads 32. The one or more second coolant passages 56 are upward coolant flow passages in that the one or more second coolant passages 56 are configured to allow coolant to flow upward from the second coolant cavity 50 to the one or more cylinder heads 32. The one or more second coolant passages 56 are sized and arranged such that coolant converges in the second coolant cavity.

[0024] Each of the one or more cylinder heads 32 includes a third coolant cavity 60, referred to as an upper cooling jacket, and a fourth coolant cavity 62, referred to as a lower cooling jacket. The third coolant cavity 60 and the fourth coolant cavity 62 of each of the one or more cylinder heads 32 can be configured in any suitable manner, such as in various shapes, sizes, and locations within the one or more cylinder heads 32. One or more second coolant passages 56 extend from the second coolant cavity 50 of each of the one or more cylinder heads 32 to the third coolant cavity 60. Thus, each of the one or more second coolant passages 56 includes a first portion 63 of the coolant passage in the engine block 12 and a second portion 65 of the coolant passage in the one or more cylinder heads 32. The first portion 63 and the second portion 65 of each second coolant passage 56 are aligned to allow flow from the first portion 63 to the second portion 65 when each cylinder head 32 is assembled to the engine block 12.

[0025] exist Figure 1 , a single second coolant passage 56 is shown for simplicity. However, the one or more second coolant passages 56 may be configured in any suitable manner, such as various shapes, sizes, number of passages, and locations of passages in the engine block 12 and the one or more cylinder heads 32. In some embodiments, a second coolant passage 56 is associated with each cylinder 16. Thus, for example, Figure 6 As shown, for an engine 10 having six cylinders 16, there are six second coolant passages 56 for guiding coolant from the second coolant chamber 50 to the third coolant chamber 60. Figure 4 and Figure 6 As shown, in the illustrated embodiment, one of the plurality of second coolant passages 56 extends through the platform 30 at a location adjacent to each cylinder 16 and between each cylinder 16 and the first side 22 of the engine block 12 such that the plurality of second coolant passages 56 are evenly spaced along the length of the engine block 12 and aligned with each cylinder 16 .

[0026] In the illustrated embodiment, the size and arrangement of the plurality of second coolant passages 56 relative to the second coolant cavity 50, and the relatively larger size and arrangement of the second coolant cavity 50, serve to create a pool of coolant in the second coolant cavity 50 along the engine block 12. The pool of coolant, which in the illustrated embodiment extends from the first end 18 to the second end 20 of the engine block 12, uniformly supplies coolant to the spaced-apart plurality of second coolant passages 56 to provide uniform coolant flow into the third coolant cavity 60.

[0027] The third coolant cavity 60 in each of the one or more cylinder heads 32 is adjacent to the top end 33 of each cylinder head 32. The third coolant cavity 60 is in fluid communication with the second coolant cavity 50 via the plurality of second coolant passages 56. The third coolant cavity 60 in each of the one or more cylinder heads 32 is configured to cool cylinder head components near the top end 33 and in the middle of each cylinder head 32.

[0028] The fourth coolant cavity 62 is in fluid communication with the third coolant cavity 60 and is configured to receive coolant from the third coolant cavity 60 via one or more third coolant passages 67. The fourth coolant cavity 62 in each of the one or more cylinder heads 32 is below the third coolant cavity 60 and adjacent the bottom end 35 of each cylinder head 32. The fourth coolant cavity 62 in each of the one or more cylinder heads 32 is configured to cool cylinder head components.

[0029] The engine 10 includes a fifth coolant cavity 64, referred to as a cylinder liner cooling jacket, located in the engine block 12 surrounding the cylinder liners 14. The third coolant cavity 60 and the fourth coolant cavity 62 can be configured in any suitable manner, such as in various shapes, sizes, and locations within one or more cylinder heads 32. The fifth coolant cavity 64 is located adjacent to and below the deck 30 of the engine block 12 and extends between the cylinder liners 14 such that the cylinders 16 are cooled by coolant passing through the fifth coolant cavity 64 and contacting the cylinder liners 14.

[0030] The engine 10 includes one or more fourth coolant passages 66 that extend from the fourth coolant cavity 62 in each of the one or more cylinder heads 32 to the fifth coolant cavity 64. The one or more fourth coolant passages 66 are downward coolant flow passages because the one or more fourth coolant passages 66 are configured to allow coolant to flow downward from the fourth coolant cavity 62 to the fifth coolant cavity 64. Thus, each of the one or more fourth coolant passages 66 includes a first portion (not shown) of a coolant passage in the engine block 12 and a second portion (not shown) of a coolant passage in one of the one or more cylinder heads 32. The first portion and the second portion of each fourth coolant passage 66 are aligned to allow flow from the first portion to the second portion when each cylinder head 32 is assembled to the engine block 12.

[0031] exist Figure 1 , a single fourth coolant passage 66 is shown for simplicity. However, in some embodiments, a fourth coolant passage 66 is associated with each cylinder 16 (ie, one coolant passage per cylinder). Figure 6 As shown, for example, for an engine 10 having six cylinders 16, there are six fourth coolant passages 66, one for each cylinder, for directing coolant from the fourth coolant cavity 62 to the fifth coolant cavity 64. Figure 4 and Figure 6 As shown, in the illustrated embodiment, one of the plurality of fourth coolant passages 66 extends through the platform 30 at a location adjacent to each cylinder 16 and near the second side 24 of the engine block 12, such that the plurality of fourth coolant passages 66 are evenly spaced along the length of the engine block 12 and aligned with each cylinder 16. However, in other embodiments, the number of fourth coolant passages 66 may be greater or less than the number of cylinders 16.

[0032] The engine 10 includes a sixth coolant cavity 68, referred to as an outlet rail, that is laterally adjacent to the fifth coolant cavity 64 and in fluid communication with the fifth coolant cavity 64 via one or more fifth coolant passages (not shown). The sixth coolant cavity 68 extends along the first side 22 of the engine block 12 above the second coolant cavity 50. The sixth coolant cavity 68 is in fluid communication with a coolant outlet 70, where coolant exits the engine block 12.

[0033] The second coolant cavity 50 and the sixth coolant cavity 68 are larger than the third, fourth, and fifth coolant cavities 60, 62, 64. The larger size of the second coolant cavity 50 and the sixth coolant cavity 68 helps evenly distribute the coolant throughout the engine 10, particularly within the fifth coolant cavity 64.

[0034] Industrial Applicability

[0035] The internal combustion engine 10 having the coolant flow path and internal coolant passages of the present invention can be used in a variety of applications, such as for powering off-road trucks, railroad locomotives, earth-moving machines, engine-driven generators or pumping systems, or other engine power applications. The exemplary embodiment of the engine 10 includes a top-down coolant flow from one or more cylinder heads 32 to the cylinder liner cooling jackets. The top-down coolant flow and coolant flow path arrangement provides more efficient and uniform cooling of the cylinder liners 14 and cylinder heads 32.

[0036] In particular, coolant enters the first coolant cavity 46 and flows longitudinally along the length of the engine block 12 (ie, at Figure 1 The coolant then flows upward (i.e., in Figure 1 The coolant flows vertically (in the middle) into the second coolant cavity 50 which extends along the length of the engine block 12. Due to the large size of the second coolant cavity 50 relative to the plurality of second coolant passages 56, the coolant will converge in the second coolant cavity 50.

[0037] The coolant from the second coolant cavity 50 then flows into the third coolant cavity 60 in one or more cylinder heads 32 via the plurality of second coolant passages 56, while avoiding the fifth coolant cavity 64 (i.e., the cylinder liner cooling jacket). In the exemplary embodiment, the coolant flow into the third coolant cavity 60 is evenly or nearly evenly distributed due to the presence of the second coolant passages 56 adjacent to and associated with each cylinder 16 and the coolant sump that feeds the second coolant passages 56.

[0038] With the third cooling liquid cavity 60 above the fourth cooling liquid cavity and the fourth cooling liquid cavity above the fifth cooling liquid cavity 64, the flow from the third cooling liquid cavity to the fourth cooling liquid cavity and from the fourth cooling liquid cavity to the fifth cooling liquid cavity is downward and gravity-assisted. Coolant from the fourth cooling liquid cavity 62 flows downward into the fifth cooling liquid cavity 64 via the plurality of fourth cooling liquid channels 66. In the exemplary embodiment, because the second cooling liquid cavity 50 and the sixth cooling liquid cavity 68 are larger relative to the third, fourth, and fifth cooling liquid cavities 60, 62, 64, the coolant flow through the third, fourth, and fifth cooling liquid cavities 60, 62, 64 is evenly or nearly evenly distributed.

[0039] Coolant flowing into the fifth coolant cavity 64 initially flows downward; thus, the coolant begins at the hottest portion of the cylinder liner 14, near the land 30, and passes downward along the side of the cylinder liner 14. Within the fifth coolant cavity 64, the coolant will also flow laterally around and between each cylinder liner 14 from the second side 24 to the first side 22 of the engine block 12. However, because a separate fourth coolant passage 66 is associated with each cylinder liner 14, the cylinder liners 14 are cooled in parallel rather than sequentially. Thus, unlike conventional designs where coolant flows longitudinally along the cylinders, which results in uneven, sequential cooling of the cylinders, in the engine 10 of the present invention, coolant flow through the fifth coolant cavity 64 and the subsequent cooling of the cylinders 16 is uniform.

[0040] Although the present invention has been illustrated by describing its embodiments, and the embodiments have been described in considerable detail, the applicant does not intend to restrict or in any way limit the scope of the appended claims to such details. Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details, representative compositions or concepts, and illustrative examples shown and described. Therefore, departures may be made from such details without departing from the spirit or scope of the applicant's general disclosure.

Claims

1. An internal combustion engine comprising: a plurality of cylinder liners defining a plurality of cylinders; An engine block for accommodating the plurality of cylinder liners, the engine block comprising: upper plane surface; a cylinder liner cooling jacket below the upper planar surface and in fluid communication with the plurality of cylinder liners; one or more cylinder heads attached to the upper planar surface of the engine block, each of the one or more cylinder heads including one or more cylinder head cooling jackets; a coolant chamber in the engine block, the coolant chamber being separated from the cylinder liner cooling jacket; one or more upward coolant passages extending from the coolant cavity to the one or more cylinder head cooling jackets while avoiding the cylinder liner cooling jackets for conveying coolant from the coolant cavity to the one or more cylinder head cooling jackets; one or more downward coolant passages extending from the one or more cylinder head cooling jackets to the cylinder liner cooling jacket for conveying coolant from the one or more cylinder head cooling jackets to the cylinder liner cooling jacket; It is characterized in that the coolant cavity is located below the cylinder liner cooling jacket, and the size and arrangement of the one or more upward coolant channels enable the coolant to converge in the coolant cavity.

2. The internal combustion engine according to claim 1, wherein The number of the plurality of cylinders in the engine is equal to the number of the plurality of downward coolant passages and equal to the number of the plurality of upward coolant passages.

3. The internal combustion engine according to claim 1, wherein The one or more cylinder head cooling jackets include an upper cooling jacket and a lower cooling jacket below the upper cooling jacket, and wherein the one or more upward coolant passages extend into the upper cooling jacket.

4. The internal combustion engine of claim 1 , further comprising a coolant pump and a second coolant cavity in the engine block below the coolant cavity, wherein the second coolant cavity is configured to receive coolant from the coolant pump, and the coolant cavity in the engine block is configured to receive coolant from the second coolant cavity.

5. The internal combustion engine according to claim 1, wherein The one or more cylinder head cooling jackets include an upper cooling jacket and a lower cooling jacket below the upper cooling jacket, and wherein the one or more downward coolant passages extend from the lower cooling jacket.

6. A method of cooling an internal combustion engine according to any one of claims 1 to 5, the internal combustion engine having one or more cylinder heads attached to an upper planar surface of an engine block, the engine block housing a plurality of cylinder liners, the method comprising: pumping coolant into the engine block beneath the plurality of cylinder liners; Directing the coolant upward into the coolant cavity where it converges; directing coolant from the coolant cavity to the one or more cylinder heads while avoiding cooling the plurality of cylinder liners; and Coolant is directed from the one or more cylinder heads downwardly into the engine block adjacent the plurality of cylinder liners to cool the cylinder liners.

7. The method of claim 6, wherein pumping coolant into the one or more cylinder heads further comprises pumping coolant into an upper cooling jacket of the one or more cylinder heads and directing the coolant from the upper cooling jacket downwardly to a lower cooling jacket of the one or more cylinder heads.

8. The method of claim 6, wherein directing coolant from the one or more cylinder heads downwardly into the engine block further comprises directing a plurality of coolant streams downwardly, wherein the number of the plurality of coolant streams downwardly is equal to the number of the plurality of cylinder liners.

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