Internal combustion engines may generate blowby gas during engine operation such as by intake air and exhaust gases traveling past piston rings, stem seals, compressor or turbine seals, or other engine components. Gaseous crankcase fluid, include blowby gas, is mostly contained in the crankcase where its pressure may be regulated using an open or closed crankcase ventilation system. In an open crankcase ventilation system, the crankcase fluid may be ventilated out of the engine to regulate crankcase pressure. In a closed crankcase ventilation system, the crankcase fluid may be ventilated into an intake air circuit or another location having a pressure below the pressure of the crankcase fluid such that the crankcase fluid is reintroduced to the engine.
Various aspects of examples of the present disclosure are set out in the claims.
In an embodiment of the present disclosure, an internal combustion engine includes a block containing a crankshaft and a crankcase surrounding the crankshaft, a plurality of combustion chambers configured to receive an intake fluid and generate exhaust fluid, an exhaust circuit configured to direct the exhaust fluid away from the plurality of combustion chambers, an intake circuit configured to supply the intake fluid to the plurality of combustion chambers, a turbine disposed in the exhaust circuit and having a turbine shaft configured to be driven by the exhaust fluid, a crankcase ventilation circuit configured to direct crankcase fluid away from the crankcase, and a pump disposed in the crankcase ventilation circuit and having a rotor configured to be driven by the turbine shaft to propel the crankcase fluid through the crankcase ventilation circuit.
The engine may further include a compressor disposed in the intake circuit propelling the intake fluid to the plurality of combustion chambers. The engine may further include a crankcase ventilation circuit outlet disposed at the intake circuit downstream from the compressor such that the crankcase fluid is propelled from the crankcase to the intake circuit through the crankcase ventilation circuit. The engine may further include a separator disposed in the crankcase ventilation circuit and configured to remove a lubricant from the crankcase fluid as the crankcase fluid is directed through the crankcase ventilation circuit. The separator may be disposed upstream of the pump in the crankcase ventilation circuit. The engine may further include a regulator disposed in the crankcase ventilation circuit and configured to regulate the pressure of the crankcase fluid in the crankcase. The regulator may be disposed upstream of the pump in the crankcase ventilation circuit. The engine may further include a check valve disposed in the crankcase ventilation circuit and configured to prevent a reverse flow direction of the crankcase fluid from the crankcase ventilation circuit outlet toward the pump. The check valve may be disposed downstream of the pump in the crankcase ventilation circuit. The engine may further include a crankcase ventilation circuit outlet disposed at the exhaust circuit downstream of the turbine such that the crankcase fluid is propelled from the crankcase to the exhaust circuit through the crankcase ventilation circuit.
In an embodiment of the present disclosure, a crankcase ventilation system is configured to ventilate a crankcase in an internal combustion engine having a turbine. Th crankcase ventilation system includes a crankcase ventilation circuit configured to direct crankcase fluid away from the crankcase, a pump disposed in the crankcase ventilation circuit and being configured to be driven by the turbine to propel the crankcase fluid through the crankcase ventilation circuit, a check valve disposed in the crankcase ventilation circuit downstream of the pump and being configured to prevent a reverse flow direction of the crankcase fluid toward the pump, and a separator disposed in the crankcase ventilation circuit and configured to remove a lubricant from the crankcase fluid as the crankcase fluid is directed through the crankcase ventilation circuit.
The separator may be disposed in the crankcase ventilation circuit upstream of the pump. The system may further include a crankcase ventilation circuit outlet configured to be positioned at an intake circuit downstream of a compressor propelling an intake fluid in the intake circuit, wherein the crankcase fluid may be propelled from the crankcase to the intake circuit through the crankcase ventilation circuit. The system may further include a crankcase ventilation circuit outlet configured to be positioned at an exhaust circuit downstream of the turbine, wherein the crankcase fluid may be configured to be propelled from the crankcase to the exhaust circuit through the crankcase ventilation circuit.
The above and other features will become apparent from the following description and accompanying drawings.
The detailed description of the drawings refers to the accompanying figures in which:
Like reference numerals are used to indicate like elements throughout the several figures.
At least one embodiment of the subject matter of this disclosure is understood by referring to
Reference is now made to
The engine 10 further includes an exhaust circuit 30 configured to direct the exhaust fluid 24 away from the combustion chambers 20. The engine 10 further includes an intake circuit 32 configured to supply the intake fluid 22 to the combustion chambers 20. The engine 10 illustrated in
The engine 10 and system 100 of
The engine 10 and the system 100 illustrated in the embodiment of
Referring now to
Referring now to
In order to handle the crankcase fluid 42, the rotor 50, the impeller 58, the volute 60, and/or another portion of the pump 48 and/or other component of the crankcase ventilation circuit 40 of one or more embodiments includes one or more corrosion resistant materials, coatings, and/or treatments, such as certain components being made from stainless steel in a non-limiting example. Additionally, in one or more additional embodiments, the pump 48 and/or another component of the crankcase ventilation circuit 40 includes one or more gaseous or liquid heat exchangers, such as, in non-limiting examples, air, water, or coolant jackets, passages, fins, or features, in order to cool the pump 48 and/or other component and prevent or reduce coking of the crankcase fluid 42.
Referring now to
The separator 52 of the illustrated embodiments is disposed upstream of the pump 48 in the crankcase ventilation circuit 40. The separator 52 reduces or prevents oil droplets 70 reaching the pump 48, another component in the crankcase ventilation circuit 40, and/or the intake circuit 32 or the exhaust circuit 30, depending on the arrangement of the crankcase ventilation circuit 40. Such prevention or reduction via the separator 52 improves the efficiency, durability, and performance of the pump 48 and other components of the engine 10 and the system 100.
Referring now to
During operation of an embodiment, as the speed of the turbine shaft 96 and/or the rotor 50 increases, the regulator 54 actuates toward closing the crankcase ventilation circuit 40 in order to maintain the flow rate in the crankcase ventilation circuit 40. Such actuation of the regulator 54 varies in one or more embodiments depending upon altitude of the engine 10 during operation, engine load, and/or one or more additional factors or conditions. Further, in an additional embodiment, a crankcase pressure sensor (not shown) may be provided to send feedback, such as to a controller, for operation of an electronically controlled regulator.
The engine 10 of one or more embodiments further includes a check valve 56 disposed in the crankcase ventilation circuit 40. The check valve 56 is configured to prevent a reverse flow direction of the crankcase fluid 42 from the crankcase ventilation circuit outlet 46 toward the pump 48. In other words, the check valve 56 allows flow of the crankcase fluid 42 from the pump 48 through the check valve 56 but prevents flow of the crankcase fluid 42 in a direction toward the pump 48 and/or the crankcase 16. The check valve 56 in an embodiment is disposed downstream of the pump 48 in the crankcase ventilation circuit 40. The check valve 56 in additional embodiments is disposed upstream of the pump 48 or at another location in the crankcase ventilation circuit 40. In the embodiment(s) that may include an electronically controlled regulator, the check valve 56 may be omitted.
The engine 10 and the system 100 of the embodiments described herein provide crankcase ventilation for crankcase fluid 42, such as blowby gases, generated within the engine 10. More particularly, the pump 48 and/or other components of the engine 10 and the system 100 allow the crankcase fluid 42 to be circulated as a gas to a location having a higher pressure than a pressure in the crankcase 16. In embodiments where the crankcase ventilation circuit outlet 46 is located in the intake circuit 32, the engine 10 and the system 100 provide a closed crankcase ventilation system that circulates the crankcase fluid 42 downstream of the compressor 38 to avoid introducing the crankcase fluid 42 to the compressor 38 and thereby causing adverse effects to the compressor 38 or its performance. Likewise, in embodiments where the crankcase ventilation circuit outlet 46 is located in the exhaust circuit 30, the engine 10 and the system 100 provide an open or semi-open crankcase ventilation system that circulates the crankcase fluid 42 downstream of the turbine 36 to avoid introducing the crankcase fluid 42 to the turbine 36 and thereby causing adverse effects to the turbine 36 or its performance.
As used herein, “e.g.” is utilized to non-exhaustively list examples and carries the same meaning as alternative illustrative phrases such as “including,” “including, but not limited to,” and “including without limitation.” As used herein, unless otherwise limited or modified, lists with elements that are separated by conjunctive terms (e.g., “and”) and that are also preceded by the phrase “one or more of,” “at least one of,” “at least,” or a like phrase, indicate configurations or arrangements that potentially include individual elements of the list, or any combination thereof. For example, “at least one of A, B, and C” and “one or more of A, B, and C” each indicate the possibility of only A, only B, only C, or any combination of two or more of A, B, and C (A and B; A and C; B and C; or A, B, and C). As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. Further, “comprises,” “includes,” and like phrases are intended to specify the presence of stated features, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and/or groups thereof.
While the present disclosure has been illustrated and described in detail in the drawings and foregoing description, such illustration and description is not restrictive in character, it being understood that illustrative embodiment(s) have been shown and described and that all changes and modifications that come within the spirit of the present disclosure are desired to be protected. Alternative embodiments of the present disclosure may not include all of the features described yet still benefit from at least some of the advantages of such features. Those of ordinary skill in the art may devise their own implementations that incorporate one or more of the features of the present disclosure and fall within the spirit and scope of the appended claims.