阅读说明：本技术 发动机组件 (Engine assembly ) 是由 G·柯尔斯 O·埃尔斯 P·拉马萨米 M·夏扎基斯 于 2021-03-11 设计创作，主要内容包括：本发明涉及一种发动机组件,其包括曲轴箱、曲轴、润滑系统和流体引导布置。在旋转期间,曲轴被配置成驱动曲轴箱室中的曲轴箱流体流。润滑系统包括润滑剂排放口,该润滑剂排放口用于使穿过其中的排放流体流延伸至曲轴箱室处的排放孔。流体引导布置被定位成与排放孔邻近或靠近。流体引导布置被配置成引导曲轴箱流体流远离排放孔和/或用于减小曲轴箱流体流经过排放孔的压力,使得排放流体从润滑剂排放口流出。(An engine assembly includes a crankcase, a crankshaft, a lubrication system, and a fluid routing arrangement. During rotation, the crankshaft is configured to drive a crankcase fluid flow in the crankcase chamber. The lubrication system includes a lubricant drain port for casting a drain fluid therethrough to a drain hole at the crankcase chamber. The fluid directing arrangement is located adjacent or near the discharge aperture. The fluid directing arrangement is configured to direct the flow of crankcase fluid away from the drain hole and/or for reducing a pressure of the flow of crankcase fluid through the drain hole such that the drain fluid flows out of the lubricant drain.)

1. An engine assembly, comprising:

a crankcase comprising a crankcase chamber at least partially formed in an inner surface of the crankcase;

a crankshaft rotatably mounted in the crankcase chamber, wherein, during rotation, the crankshaft is configured to drive a crankcase fluid flow within the crankcase chamber;

a lubrication system including a lubricant drain port for drain fluid flow therethrough, the lubricant drain port extending through the crankcase to a drain hole at the crankcase chamber; and

a fluid directing arrangement mounted to the crankcase, extending from the crankcase interior surface into the crankcase chamber and adjacent or proximate to the drain hole, the fluid directing arrangement configured to direct the crankcase fluid flow away from the drain hole and/or for reducing a pressure of the crankcase fluid flow through the drain hole such that the drain fluid flows out of the lubricant drain hole.

2. The engine assembly of claim 1, wherein the fluid directing arrangement comprises a first fluid directing wall mounted to the crankcase within the crankcase chamber and at least partially above and/or extending upstream from the drain aperture.

3. The engine assembly of claim 2, wherein the first fluid guide wall extends into the crankcase chamber toward the crankshaft and includes a first wall surface configured to direct the crankcase fluid flow away from the drain hole and/or toward the crankshaft.

4. The engine assembly of claim 3, wherein the first wall surface is concave and extends inwardly toward and/or into the crankcase to direct the crankcase fluid flow away from the drain and/or toward the crankshaft.

5. The engine assembly of any of claims 2 to 4, wherein the first fluid directing wall extends at least partially over the drain hole such that a flow of drain fluid exiting the drain hole is directed at least partially onto the first fluid directing wall, and/or the first fluid directing wall is configured to redirect the flow of drain fluid exiting the lubricant drain hole and into the flow of crankcase fluid.

6. The engine assembly of any of the preceding claims, wherein the fluid directing arrangement is configured to direct a flow of crankcase fluid through the drain hole and induce a negative pressure within the crankcase chamber adjacent the drain hole relative to a pressure in the lubricant drain hole.

7. An engine assembly according to claim 6, wherein the fluid directing arrangement is arranged to form a constriction between the fluid directing arrangement and the crankshaft to reduce the pressure of the crankcase fluid flow therethrough.

8. The engine assembly of claim 7, wherein the fluid directing arrangement comprises a throat portion and/or a converging portion upstream of the bleed hole and/or comprises a diverging portion, the bleed hole being located in or upstream of the diverging portion.

9. The engine assembly of any of claims 2-8, wherein the first fluid directing wall is closer to the crankshaft than a portion of the crankcase downstream of the drain hole.

10. The engine assembly of any of claims 2 to 9, wherein the first fluid directing wall extends from a first wall proximal end adjacent the exhaust aperture to a first wall distal end, and a spacing between the first fluid directing wall and the crankshaft increases from the first wall proximal end to the first wall distal end.

11. The engine assembly of any of claims 2 to 9, wherein the first fluid directing wall extends from a first wall proximal end adjacent the exhaust aperture to a first wall distal end, and a spacing between the first fluid directing wall and the crankshaft increases from the first wall distal end to the first wall proximal end.

12. The engine assembly of any preceding claim, wherein the fluid directing arrangement comprises a second fluid directing wall extending from a second wall proximal end adjacent the discharge aperture to a second wall distal end, and a spacing between the second fluid directing wall and the crankshaft increases from the first wall proximal end to the first wall distal end.

13. An engine assembly according to any preceding claim, wherein the fluid directing arrangement is integrally formed with the crankcase and/or comprises at least one plate attached to the crankcase.

14. The engine assembly of any of the preceding claims, further comprising a turbocharger, wherein the lubrication system distributes lubricant to the turbocharger, and the lubricant drain is configured to direct lubricant from the turbocharger to the crankcase chamber.

15. A method of operating an engine assembly according to any preceding claim, comprising:

rotating the crankshaft, thereby driving a crankcase fluid flow within the crankcase chamber; and

operating the lubrication system such that a flow of discharge fluid passes through the lubricant drain port to the drain hole,

wherein the fluid directing arrangement directs the crankcase fluid flow away from the drain hole and/or reduces a pressure of the crankcase fluid flow through the drain hole such that the drain fluid flows out of the lubricant drain hole.

Technical Field

The invention relates to an engine assembly and a method of operating the same.

Background

Machines, including backhoe loaders, excavators, loaders, and the like, typically include an engine assembly that includes an engine, particularly an internal combustion engine, for powering the machine and operating its components. Engines typically include a crankshaft that rotates within a crankcase, and a lubrication system typically distributes lubricant through the crankshaft into the crankcase. The engine assembly also typically includes a turbocharger driven by exhaust gas from the engine and used to compress intake air entering the engine to increase its power output.

The turbocharger may also receive lubricant from the lubrication system and the lubricant may be returned to the crankcase via a lubricant drain. However, high pressure in the crankcase may force lubricant and/or high pressure back into the lubricant drain (e.g., due to crankshaft windage) and cause a pressure differential in the turbocharger. As a result, seals in the turbocharger may be damaged and lubricant may leak from the turbocharger.

KR101251711B1 discloses a closed crankcase ventilation fan for preventing backflow of oil drained into an oil pan and supplying blow-by gas into an air intake of an engine. However, such ventilators require additional equipment and system components in the engine assembly, and may also locally increase the pressure around the ventilator.

Disclosure of Invention

Accordingly, the present invention provides an engine assembly comprising: a crankcase comprising a crankcase chamber at least partially formed within an interior surface of the crankcase; a crankshaft rotatably mounted within the crankcase chamber, wherein during rotation, the crankshaft is configured to drive a crankcase fluid flow within the crankcase chamber; a lubrication system including a lubricant drain port for flow of drain fluid therethrough, the lubricant drain port extending through the crankcase to a drain hole at the crankcase chamber; and a fluid directing arrangement mounted to the crankcase, extending into the crankcase chamber from the crankcase interior surface and adjacent or proximate to the drain hole, the fluid directing arrangement being configured for directing a flow of crankcase fluid away from the drain hole and/or for reducing a pressure of the crankcase fluid flow through the drain hole such that the drain fluid flows out of the lubricant drain hole.

The present invention further provides a method of operating the engine assembly described above, comprising: rotating the crankshaft to drive a crankcase fluid flow within the crankcase chamber; and operating the lubrication system such that the flow of the drain fluid flows through the lubricant drain port to the drain hole, wherein the fluid directing arrangement directs the flow of the crankcase fluid away from the drain hole and/or reduces a pressure of the flow of the crankcase fluid through the drain hole such that the drain fluid flows out of the lubricant drain port.

Drawings

Embodiments of the apparatus and method of the present invention will now be described, by way of example only, with reference to and as illustrated in the accompanying drawings, in which:

FIG. 1 is a schematic illustration of an engine assembly according to the present disclosure;

FIG. 2 is a cross-sectional side view through a piston of the engine assembly of FIG. 1;

FIG. 3 is a cross-sectional side view through another embodiment of a piston of the engine assembly of FIG. 1;

FIG. 4 is a cross-sectional side view through another embodiment of a crankshaft web of the engine assembly of FIG. 1; and is

FIG. 5 is a cross-sectional side view through another embodiment of a crankshaft web of the engine assembly of FIG. 1.

Detailed Description

The present disclosure is generally directed to an engine assembly in which a fluid directing arrangement is configured to reduce the effect of windage effects on lubricant draining from a lubricant drain. Specifically, the fluid directing arrangement directs fluid flow in the crankcase to assist fluid flow from the lubricant drain. The fluid directing arrangement may direct the flow of the draining fluid by directing the flow of the crankcase fluid away from the lubricant drain and/or by inducing a negative pressure in the flow of the crankcase fluid to draw the flow of the draining fluid out of the lubricant drain.

FIG. 1 illustrates an exemplary embodiment of an engine assembly 10 according to the present disclosure. The engine assembly 10 may include an intake system 11 for directing intake air, such as atmospheric air, to a turbocharger 12. The turbocharger 12 may include a compressor 13 in fluid communication with the intake system 11, and the compressor 13 may be arranged to be driven by a turbine 14 via a shaft 15.

The engine assembly 10 further includes an engine 16, which may be arranged to receive compressed intake air from the compressor 13. The engine 16 may be in fluid communication with the turbine 14 and direct exhaust gas to the turbine 14 for driving the turbine 14. The turbine 14 may be in fluid communication with an exhaust system 17 for directing exhaust gases from the engine assembly 10 to the atmosphere.

Although not shown, the engine assembly 10 may include a supercharger for further compressing the intake air entering the engine 16, an exhaust gas recirculation system, an aftertreatment system for treating the exhaust gas in the exhaust system 17 to remove pollutants, before directing the exhaust gas to the atmosphere, etc.

The engine 16 may be an internal combustion engine, such as a compression ignition or spark ignition engine, and embodiments thereof are shown in greater detail in FIG. 2. The engine 16 includes a crankcase 22. The engine 16 may include an engine block 20, which may include at least one engine cylinder 21 and a crankcase 22. The at least one engine cylinder 21 may include at least one aperture in the engine block 20 and the crankcase 22 may be integrated within the engine block 20 (e.g., the crankcase 22 and the at least one aperture may be formed by the unitary engine block 20). The engine block 20 may be cast to include at least one engine cylinder 21 and at least a portion of a crankcase 22, such as at least an upper portion of the crankcase 22 as shown.

The crankcase 22 includes a crankcase chamber 23, the crankcase chamber 23 being at least partially formed within a crankcase interior surface 26 of the crankcase 22. A lower portion of the crankcase 22 (i.e., opposite the at least one engine cylinder 21) may be open, and a lower housing (not shown) may be attached to the crankcase 22 to enclose a crankcase chamber 23 within the engine block 20, the crankcase 22, and the lower housing. The lower housing may include a lubricant sump pan.

The engine 16 may include at least one piston 24 reciprocally mounted within at least one engine cylinder 21. The at least one piston 24 may be configured to reciprocate along the piston reciprocation axis 19. The engine 16 may include at least one intake valve (not shown) for selectively allowing intake air, which may be received from the turbocharger 12 and the intake system 11, to enter the at least one engine cylinder 21. The engine 16 may include at least one exhaust valve (not shown) for selectively allowing exhaust gas resulting from combustion to exit the at least one engine cylinder 21, which may exit the engine assembly 10 via the turbocharger 12 and the exhaust system 17.

The engine 16 includes a crankshaft 30 rotatably mounted in the crankcase 22 and the crankcase chamber 23. The crankshaft 30 may rotate about a crankshaft axis 31 in a crankshaft rotational direction 36. The at least one piston 24 may be mounted to a crankshaft 30 via at least one connecting rod 25, and the crankshaft 30 may be configured to provide a power output from the engine 16 when rotating about a crankshaft axis 31.

Fuel, such as diesel, gasoline, or natural gas, may be selectively provided to at least one engine cylinder 21 to combust with the intake air and drive at least one piston 24 to rotate a crankshaft 30 and provide engine 16 output torque and power.

Crankshaft 30 may be mounted to main bearings (not shown) of engine 16. Crankshaft 30 may include journal 32. The journal 32 may include at least one rod journal 32 (shown in fig. 2) to which the at least one connecting rod 25 may be rotatably mounted and may include at least one main journal (not shown) for rotatably mounting in the main bearing. The at least one rod journal 32 may be offset from the crankshaft axis 31 and the at least one main journal may be aligned with the crankshaft axis 31.

The crankshaft 30 may include at least one crankshaft web 33 that may be connected to and extend between adjacent shaft journals 32. The at least one crankshaft web 33 may track and/or form a crankshaft outer circumference 37 of the crankshaft 30 during rotation thereof. When the at least one crankshaft web 33 forms the outermost diameter of the crankshaft 30, the crankshaft outer circumference 37 may represent the outermost limit reached by the crankshaft 30 throughout its rotation.

The engine assembly 10 includes a lubrication system 40 for distributing lubricant, such as oil, therearound. The lubrication system 40 may include a lubricant collection trough or reservoir, which may be in the form of a lubricant trough pan, located in the lower housing. The lubrication system 40 may include at least one pump (not shown) for pumping lubricant therearound.

Lubrication system 40 may include a crankshaft lubrication system 34 for distributing lubricant to journals 32, and as shown, crankshaft lubrication system 34 may include at least one conduit formed within crankshaft 30. The at least one pump may direct lubricant through crankshaft 30 to journal 32. Lubricant may be sprayed from the journal 32 into the crankcase chamber 23 and collected in a lubricant collection sump.

The lubrication system 40 includes a lubricant drain 42 for draining the fluid flow 38 therethrough. The drain fluid may include lubricant and/or air or gas, and the lubricant drain 42 may be used to return the drain fluid to the collection tank. As shown in fig. 2-5, the lubricant drain port 42 may extend through the engine block 20 and the crankcase 22 to the crankcase chamber 23 such that drain fluid flowing therethrough may be directed toward the lubricant sump pan. The lubrication system 40 includes a drain hole 46 at the crankcase inner surface 26 and the lubricant drain 42 extends to the drain hole 46.

The lubricant drain 42 may include at least one drain passage 43 extending through the crankcase 22 and to a drain hole 46. The at least one exhaust passage 43 may include at least one hole through the engine block 20, and optionally cast or drilled into the engine block 20. The lubricant drain port 42 may include at least one drain tube 44 mounted to the at least one drain passage 43, for example, via a drain flange 45.

The lubrication system 40 may distribute lubricant to the turbocharger 12, as shown in FIG. 1. The lubrication system 40 may thus include a turbocharger lubricant inlet arrangement 41 for directing lubricant from the sump to the turbocharger 12. The lubricant drain 42 may be used to direct a flow of drain fluid 38, which includes at least a portion of the lubricant entering the turbocharger 12, from the turbocharger 12 to the crankcase chamber 23 and thus onto the lubricant collection sump. The at least one exhaust pipe 44 may extend from the at least one exhaust passage 43 to the turbocharger 12.

However, the lubrication system 40 may distribute lubricant to other components of the engine assembly 10, and the lubricant drain 42 may be configured to return drain fluid from any such component. The lubrication system 40 may thus include a plurality of lubricant drain ports 42 leading from different components.

The crankshaft 30 is configured to drive and, in use, drive a crankcase fluid flow 48 in the crankcase chamber 23. The crankcase fluid may include a lubricant, such as a lubricant sprayed from a lubricant collection sump and/or crankshaft lubrication system 34 during rotation of crankshaft 30. The crankcase fluid may include gases, such as air and/or other exhaust gases within the crankcase chamber 23. The crankshaft 30 may drive such a crankcase fluid flow 48 through windage effects. The crankcase fluid flow 48 may be annular around the crankshaft 30 and/or may be between the crankcase 22 (particularly the crankcase interior surface 26) and the crankshaft 30. The crankshaft 30 may be configured to drive a crankcase fluid flow 48, and may drive the crankcase fluid flow 48 toward the drain 46 during use. The crankcase fluid flow 48 may extend through the drain hole 46 and may be in the same direction as the crankshaft rotational direction 36.

The engine 16 includes a fluid directing arrangement 50 mounted to the crankcase 22 and adjacent or near the drain hole 46. The fluid directing arrangement 50 extends from the crankcase interior surface 26 into the crankcase chamber 23. Specifically, the crankcase interior surface 26 may extend about at least about 50% or at least about 60% of the circumference of the crankshaft 30, and the fluid directing arrangement 50 may extend about less than about 50%, less than about 25%, or less than about 10% of the circumference of the crankshaft 30. The crankcase interior surface 26 surrounding the crankshaft 30 may be separated from the crankshaft 30 by a greater distance than the fluid routing arrangement 50.

The fluid directing arrangement 50 is configured to direct the crankcase fluid flow 48 as the crankcase fluid flow 48 passes through or near the drain hole 46. As a result, the fluid directing arrangement 50 controls the flow of the discharge fluid 38 and/or the flow of the discharge fluid 38 from the lubricant drain 42. The fluid directing arrangement 50 may be configured to redirect the crankcase fluid flow 48 and/or deviate the crankcase fluid flow 48 from its substantially circular path around the crankcase chamber 23. The fluid directing arrangement 50 is configured to direct and/or deflect the crankcase fluid flow 48 away from the drain hole 46. The fluid directing arrangement 50 additionally or alternatively reduces the pressure of the crankcase fluid flow 48 through the drain hole 46 (e.g., adjacent to the fluid directing arrangement 50) such that a negative pressure is induced in the crankcase fluid flow 48 relative to the pressure of the drain fluid flow 38 in the lubricant drain 42. Fig. 2 to 5 show different embodiments of a fluid guiding arrangement 50 according to the present invention.

The fluid directing arrangement 50 may include a first fluid directing wall 51 mounted to the crankcase 22 and located at least partially above and/or upstream of the drain hole 46, for example as shown in fig. 2-5. The term "upstream" may be in a direction opposite crankcase fluid flow 48, and may refer to a feature, such as first fluid guide wall 51, that is positioned around crankcase interior surface 26 from drain hole 46 in a direction opposite crankshaft rotational direction 36 and crankcase fluid flow 48. Accordingly, the crankcase fluid flow 48 may be driven past the first fluid guide wall 51 before flowing through the drain hole 46.

Furthermore, as shown in fig. 2-5, when engine 16 is in a vertical configuration, first fluid directing wall 51 may be located above (e.g., above but not necessarily vertically aligned with) discharge orifice 46. The first fluid guide wall 51 may guide the crankcase fluid flow 48 as the crankcase fluid flow 48 travels downward toward the drain hole 46. However, if the drain hole 46 is on an opposite side of the crankcase 22 (e.g., on the left side in fig. 2 rather than on the right side as shown), the first fluid guide wall 51 may be located below the drain hole 46 when the engine 16 is in its vertical configuration. Thus, in this arrangement, the first fluid directing wall 51 may direct the crankcase fluid flow 48 as the crankcase fluid flow 48 travels upward toward the drain hole 46.

The first fluid guide wall 51 may extend into the crankcase chamber 23 toward the crankshaft axis 31 and/or the crankshaft 30 and may include a first wall surface 52 that may extend between first wall proximal and distal ends 53, 54. The first wall proximal end 53 may be located proximal to the discharge aperture 46 and the first wall distal end 54 may be located distal to the discharge aperture 46. The first wall proximal end 53 may be downstream of the first wall distal end 54 and may be downstream of the first wall surface 52. The term "downstream" may refer to a feature that is located in the direction along the crankshaft rotational direction 36 and the crankcase fluid flow 48 and is opposite the upstream direction. The drain and crankcase fluid flows 38, 48 may be mixed together downstream of the drain 46.

As shown in fig. 2 and 3, the first fluid guide wall 51 is configured to deflect or direct fluid away from the drain hole 46, and the first wall surface 52 may be configured to direct the crankcase fluid flow 48 away from the drain hole 46 and/or toward the crankshaft 30 and/or the crankshaft axis 31. The first wall surface 52 may be configured to direct or direct the crankcase fluid flow 48 through the first wall distal end 54 toward the crankshaft axis 31 and/or the crankshaft 30 as it passes the first wall proximal end 53 such that the fluid is directed out of the drain hole 46. The first wall surface 52 may be closer to the crankshaft axis 31 at the first wall proximal end 53 than at the first wall distal end 54.

The first wall surface 52 may be substantially concave and may curve toward and/or inward and/or extend inward into the crankcase 22 to direct the crankcase fluid flow 48 away from the drain hole 46, as shown, for example, in fig. 2 and 3. As shown in fig. 2, the first wall surface 52 may be curved and may be curved into the crankcase 22.

Alternatively, as shown in fig. 3, the first wall surface 52 may comprise a plurality of portions 55, 56, 57 arranged concavely and optionally curved. Thus, the first fluid guiding wall 51 and the first wall surface 52 may comprise a plurality of portions 55, 56, 57, each portion extending in a different direction than the adjacent sections 55, 56, 57. The first portion 55 may extend from the first wall proximal end 53 substantially parallel to the crankshaft rotational direction 36. The second portion 56 may extend from the first portion 55 toward the crankcase 22 and may be substantially perpendicular to the crankshaft direction of rotation 36. The second portion 56 may separate the first portion 55 and the first wall proximal end 53 from the discharge aperture 46. The second portion 56 may be mounted directly to the crankcase 22 and form the first wall distal end 54, or, as shown in FIG. 3, may be mounted to the crankcase 22 by a third portion 57 that may extend substantially parallel to the direction of crankshaft rotation 36 to the first wall distal end 54.

First fluid directing wall 51 may extend at least partially over discharge orifice 46 and/or first wall proximal end 53 may overhang discharge orifice 46, as shown, for example, in fig. 2 and 3. Specifically, first fluid directing wall 51 may extend at least partially across discharge orifice 46 in both the crankshaft rotational direction 36 and the downstream direction. Thus, discharge fluid flow 38 exiting discharge orifice 46 may be directed, at least in part, onto first fluid directing wall 51. First fluid guide wall 51 may be configured to redirect drain fluid flow 38 exiting lubricant drain port 42 and direct drain fluid flow 38 into crankcase fluid flow 48 downstream of drain port 46. The first wall proximal end 53 may extend across at least about 25%, at least about 50%, or all of the diameter of the discharge orifice 46, which is shown in fig. 3. The lower edge 49 of the discharge orifice 46 may be chamfered, for example as shown in fig. 2, to help direct fluid in a downstream direction.

The fluid directing arrangement 50 reduces the pressure of the crankcase fluid flow 48 through the drain hole 46. The fluid directing arrangement 50 may be configured to induce a negative pressure in the crankcase chamber 23 adjacent the discharge hole 46 relative to the pressure in the lubricant drain 42. The fluid directing arrangement 50 may create a pressure differential between the crankcase fluid flow 48 in the crankcase 22 and the drain fluid flow 38 in the lubricant drain 42. The fluid directing arrangement 50 may be configured to draw 42 the drain fluid stream 38 out of the lubricant drain and into the crankcase chamber 23 to mix with the crankcase fluid stream 48. In particular, the fluid directing arrangement 50 may be configured to induce a venturi effect in the vicinity of the discharge orifice 46 to create such a negative pressure.

The fluid directing arrangement 50 may thus form a constriction between the fluid directing arrangement 50 and the crankshaft 30 to pass the crankcase fluid flow 48 therethrough. The constriction may include a converging portion and/or a throat portion and a diverging portion downstream of the converging portion and/or the throat portion. The fluid guide arrangement 50 may form a throat at its smallest distance from the crankshaft 30, for example where the first fluid guide wall 51 and the first wall surface 52 are closest to the crankshaft 30 and the crankshaft outer perimeter 37.

As shown in fig. 2 and 3, first fluid directing wall 51 may form a converging portion and/or a throat portion, and a diverging portion may be formed downstream of first wall proximal end 53. First wall surface 52 may form a converging portion and a throat, for example, by being substantially concave, and the throat may extend upstream of first wall proximal end 53. The flared portion may be formed between the first wall proximal end 53 and the discharge orifice 46. The first fluid guide wall 51, and in particular the first wall surface 52 thereof, may be closer to the crankshaft 30 and/or the crankshaft axis 31 than a portion of the crankcase inner surface 26 adjacent the drain hole 46 and downstream of the drain hole 46. As a result, the pressure of the crankcase fluid flow 48 may increase as it passes the first wall surface 52 and may decrease downstream of the first wall proximal end 53 and/or the first fluid guide wall 51. Accordingly, the crankcase fluid flow 48 adjacent the drain hole 46 may have a negative or lower pressure relative to the drain fluid flow 38 in the lubricant drain 42 such that the drain fluid flow 38 is drawn from the lubricant drain 42 by the crankcase fluid flow 48.

Alternatively, as shown in fig. 4 and 5, the fluid directing arrangement 50 may comprise an expanding portion and the discharge orifice 46 may be located in the expanding portion. In such an arrangement, the first fluid guide wall 51 may not substantially deflect the crankcase fluid flow 48 from the drain hole 46. First fluid directing wall 51 may form at least a portion of a converging portion, a throat portion, and a diverging portion. First fluid guide wall 51 may be closest to crankshaft 30, crankshaft axis 31, and/or crankshaft outer perimeter 37 at its first wall distal end 54, and first wall distal end 54 may form a converging portion and a throat. The first wall surface 52 may extend from the first wall distal end 54 to the first wall proximal end 53, and the spacing between the first wall surface 52 and the crankshaft 30, the crankshaft axis 31, and/or the crankshaft outer perimeter 37 may increase continuously, for example, from the first wall distal end 54 to the first wall proximal end 53. Thus, the first wall surface 52 may form at least a portion of the flared portion. The first wall surface 52 may be concave and may extend inwardly into the crankcase 22.

The spacing between first fluid directing wall 51 and crankshaft outer perimeter 37 at first wall proximal end 53 may be in the range of about 1mm to about 10mm or about 2mm to 7 mm. The spacing between first fluid guide wall 51 and crankshaft outer perimeter 37 at first wall distal end 54 may be in the range of about 0.1mm to about 1 mm.

Fluid directing arrangement 50 may include a second fluid directing wall 60 extending downstream from discharge orifice 46. Second fluid directing wall 60 may include a second wall surface 61 and may extend from a second wall proximal end 62 adjacent discharge orifice 46 to a second wall distal end 63 distal to discharge orifice 46. The second fluid directing wall 60 may be closest to the crankshaft 30, the crankshaft axis 31, and/or the crankshaft outer perimeter 37 at its second wall proximal end 62. The spacing between the second wall surface 61 and the crankshaft 30, the crankshaft axis 31, and/or the crankshaft outer perimeter 37 may increase continuously, for example, from the second wall proximal end 62 to the second wall distal end 63. The second wall surface 61 may thus form at least a part of the flared portion. The second wall surface 61 may be concave and may extend inwardly into the crankcase 22.

The arrangements of fig. 4 and 5 as described above are particularly suitable for inducing a negative pressure in the crankcase fluid flow 48, as compared to the negative pressure of the exhaust fluid flow 38. This may be particularly due to the crankcase fluid flow 48 between the fluid guide arrangement 50 and the crankshaft 30 having a lower pressure and a higher velocity than elsewhere between the crankshaft 30 and the crankcase inner surface 26. Where the fluid directing arrangement 50 is closest to the crankshaft 30 at the throat, which may be located at the first wall distal end 54 as shown in fig. 4 and 5, the pressure of the crankcase fluid flow 48 will be lowest. Thus, the discharge orifice 46 may be located at the throat. However, the discharge hole 46 may be located at a distance from the throat, such as in the flared portion as shown, to allow natural discharge from the discharge hole 46.

As shown in fig. 4, a centerline 70 of the at least one discharge passage 43 may extend substantially horizontally along a horizontal axis 71. It will be appreciated that the horizontal axis 71 may not always be horizontal when the engine 16 changes its orientation during use, for example when the machine is travelling over terrain undulations. However, when the engine 16 is in its illustrated vertical configuration, the horizontal axis 71 may be substantially horizontal. The horizontal axis 71 may extend in a direction substantially perpendicular to the crankshaft axis 31 and perpendicular to the piston reciprocation axis 19, although the horizontal, crankshaft and/or piston reciprocation axes 71, 31, 19 may not intersect.

However, as shown in FIG. 5, a centerline 70 of at least one discharge passage 43 may extend at an acute angle 72 with respect to a horizontal axis 71. This arrangement may assist in the drainage of the drainage fluid stream 38 by gravity. The acute angle 72 may be about 90 degrees such that the centerline 70 of the at least one discharge passage 43 extends vertically. The acute angle 72 may be at least about 10 degrees, at least about 25 degrees, at least about 45 degrees, and/or at most about 90 degrees.

As shown in fig. 2 and 3, the drain hole 46 and the fluid directing arrangement 50 may be aligned with the rod journal 32 along the crankshaft 30, such as when the fluid directing arrangement 50 is configured to deflect the crankcase fluid flow 48 away from the drain hole 46. Thus, in such an arrangement, the fluid directing arrangement 50 may deflect the crankcase fluid flow 48 between itself and the axle journal 32.

However, as shown in fig. 4 and 5, the drain holes 46 and the fluid directing arrangement 50 may be aligned with the crankshaft web 33 along the crankshaft 30. Such an arrangement may be suitable when the fluid directing arrangement 50 is configured to induce a negative pressure in the crankcase fluid flow 48, because the spacing between the fluid directing arrangement 50 and the crankshaft 30 is small. As shown in fig. 4, the crankshaft web 33 may include counterweights and may not be circular. However, as shown in fig. 5, the crankshaft web 33 may be substantially circular, and thus the negative pressure may be maintained substantially continuously between the crankshaft 30 and the fluid directing arrangement 50.

In fig. 2-5, fluid directing arrangement 50, first fluid directing wall 51, and/or second fluid directing wall 60 are positioned adjacent discharge orifice 46 with substantially no space therebetween. However, although not shown, fluid directing arrangement 50, first fluid directing wall 51, and/or second fluid directing wall 60 may be located adjacent to discharge orifice 46 and may be separate from discharge orifice 46. For example, the crankcase 22 and a portion of the crankcase interior surface 26 may extend between the vent hole 46 and the fluid directing arrangement 50, the first fluid directing wall 51, and/or the second fluid directing wall 60. The spacing may be within a range that still ensures that fluid directing arrangement 50, first fluid directing wall 51, and/or second fluid directing wall 60 are sufficiently close that they control crankcase fluid flow 48 through drain hole 46, and thus drain fluid flow 38 from lubricant drain 42. Accordingly, fluid directing arrangement 50, first fluid directing wall 51, and/or second fluid directing wall 60 may be less than about 50mm or less than about 25mm from discharge orifice 46.

The fluid directing arrangement 50, e.g., the first and/or second fluid directing walls 51, 60, may be integrally formed with the crankcase 22 and/or the engine block 20, as shown in fig. 2, 4 and 5. As shown in fig. 2, the first fluid guide wall 51 may include a lip or protrusion that extends into the crankcase chamber 23. In particular, the fluid routing arrangement 50 may be cast with the crankcase 22 and/or the engine block 20, and/or the fluid routing arrangement 50 may be part of an integral structure that includes the crankcase 22 and/or the engine block 20. Alternatively, as shown in fig. 3, the fluid guide arrangement 50, e.g., the first and/or second fluid guide walls 51, 60, may be formed separately from the crankcase 22 and/or the engine block 20 and subsequently attached to the crankcase 22 and/or the engine block 20. For example, the fluid routing arrangement 50 may include at least one plate or member and may be welded or otherwise joined to the crankcase 22 and/or the engine block 20. As a result, the fluid routing arrangement 50 may be retrofitted to existing engines 16 that do not already include such a fluid routing arrangement 50.

The fluid directing arrangement 50 may extend along the crankcase 22 and along the crankshaft axis 31 along a width (not shown in fig. 2-5). The width may be at least the maximum diameter of the vent hole 46 and/or the crankshaft web 33. The fluid directing arrangement 50 may extend at least half of the diameter of the discharge orifice 46 on either side of the discharge orifice 46. The width of the fluid directing arrangement 50 may be at least twice the diameter of the discharge orifice 46.

Fluid directing arrangement 50 may be configured to avoid impinging the flow from drain hole 46 under the weight of the lubricant. If, as noted above, the drain hole 46 is located on the opposite side of the crankcase 22 and the first fluid directing wall 51 is located below the drain hole 46 when the engine 16 is in its upright configuration, the fluid directing arrangement 50 may be arranged in a manner similar to that shown in fig. 4 and 5. Thus, the fluid directing arrangement 50 does not affect the flow of lubricant from the drain hole 46 under gravity.

Industrial applicability

Rotation of the crankshaft 30 may result in a windage effect, which may be in the form of turbulence in the air surrounding the crankshaft 30, and lubricant is thrown around the crankshaft 30 within the crankcase 22. This windage effect may be caused by air resistance or friction around the crankshaft 30. In prior art systems, the windage effect may direct the crankcase fluid flow 48 toward the drain hole 46. The turbulence may cause higher pressure near the drain hole 46 such that in prior art systems, the high pressure air and lubricant are forced back into the lubricant drain 42. As a result, in such prior art systems, a pressure differential may be created in the turbocharger 12, which may compromise the seals therein such that lubricant may leak therefrom.

However, the fluid directing arrangement 50 of the present disclosure controls, regulates, or regulates the crankcase fluid flow 48 through the drain 46, and thus controls the drain fluid flow 38 from the lubricant drain 42, such as by preventing the crankcase fluid flow 48 from backing up through the lubricant drain 42 and/or by drawing the drain fluid flow 38 from the lubricant drain 42. The fluid directing arrangement 50 may control the crankcase 22 and the drain fluid flows 48, 38 by directing the crankcase fluid flow 48 away from the drain 46 and/or by inducing a negative pressure near the drain 46 to draw the drain fluid flow 38 from the lubricant drain 42 into the crankcase fluid flow 48. Accordingly, the fluid directing arrangement 50 may reduce the windage effect at the drain hole 46 such that the higher pressure air and lubricant are not substantially forced into the lubricant drain 42.